Dental care for the psychiatric patient: chronic schizophrenia.

In recent years, there has been a shift in philosophy concerning the overall delivery of mental health services. As a result, the treatment and management of patients with various psychiatric and behavioral disorders have undergone some fundamental changes. Improved diagnostic and treatment modalities have, in many instances, reduced the need for long-term institutionalization for a large number of these patients. Consequently, community-based mental health agencies (e.g., group homes, homes for special care patients, etc.) are now assuming an increasingly important role in the long-term management of these patients, providing, for example, more sophisticated mental health promotion programs and counselling services. A greater positive interaction now exists between these individuals and the surrounding community, thereby encouraging a more favorable integration within society as a whole. Due to this shift from primarily an institutional-based treatment regimen to a more community-oriented approach, the general dental practitioner can expect to see and be requested to treat an increasing number of these patients, many of whom present with significant dental pathology. The purpose of this paper will be to provide an overview of the oral health findings and management protocols for those individuals suffering from one specific form of psychiatric illness--chronic schizophrenia. An attempt will be made to familiarize the practising dentist with the main psychopathological features of this disorder as well as the specific oral health care requirements and management protocols for these patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Comparison of dental caries and oral hygiene indices for 13- to 14-year-old Quebec children between 1977 and 1989-1990.

A comparison of the principal dental health indices of 13- to 14-year-old Quebec school children between 1977 and 1989-1990 is reported. Data derive from a dental health survey of 1,093 Quebec school children in 1977 and from a province-wide probability sample of 1,342 children in 1989-1990. The most interesting conclusions are: the DMFT index for 13- to 14-year-old children dropped from 9.0 to 4.5; an improvement in the caries treatment level from 26 per cent to 90 per cent is noted; caries treatment needs decreased from 55 per cent to nine per cent; the mean number of extracted teeth per child dropped from a score of 1.6 to a score of 0.03; significant differences in the DMFT index between residential status no longer exist; and no improvement in the oral hygiene condition (OHIS index) is observed. In 1989-1990, 35 per cent of these adolescents had perfect periodontal health. For the others, the principal problems were bleeding gums and/or calculus.


[Special considerations relating to class 1 and class 2 removable partial dentures in the mandible].

During the rehabilitation of partially edentulous patients, dentists must try to preserve the health of the remaining oral structures. That is why it is essential to make maximum use of the support areas. With removable class 1 and 2 prostheses (Kennedy-Applegate classification), the remaining teeth and the edentulous areas provide support. While virtually no movement from the teeth is noticeable, the tissues covering the edentulous ridges do move in a variable manner. A unit must therefore be designed and built to protect the remaining teeth as well as the residual ridges. The problem is all the more acute for the mandible, since the compressibility of the tissues of the edentulous ridges and remodeling of the bone are greater. Many approaches and techniques have been described in the dental literature: functional impressions, use of appropriate direct retainers, and relining of units, if necessary.


[The short- and long-term results in heart surgery of the elderly].

We have studied retrospectively 106 patients aged 69 years or older (range 69 to 79) who underwent cardiac surgery between November 1986 and December 1989. The majority of patients (61%) were male. Coronary artery bypass surgery was performed in 59 patients, isolated valve replacement in 38 and combined valve replacement with coronary artery bypass surgery in 5. Two patients underwent ascending aorta replacement for aortic dissection and 2 ventricular aneurysmectomy and postinfarction ventricular septal defect repair. The mean postoperative hospital stay was 12 days. Ninety-one percent of patients underwent a primary elective operation and 9% required an emergency operation. Hospital mortality was 5% (n = 6). All hospital survivors were followed up by telephone contact (mean follow-up: 37 months) to determine presence or absence of chest pain, dyspnea, postoperative NYHA class and the overall effect of surgery on quality of life. There were 16 follow-up deaths; 5 were non cardiac. Follow-up study showed significant improvement in symptom status and quality of life (96%). We concluded that cardiac surgery in the elderly, although associated with increased operative risk, gives excellent relief of symptoms and good survival.


[The determination of myocardial necrosis in unstable angina by the immunoradiometric measurement of circulating myosin].

Ventricular myosin heavy chains serum levels are a new marker of myocardial necrosis. We have studied plasma levels of myosin in 30 patients with unstable angina, 30 patients with acute myocardial infarction and 25 healthy subjects. The myosin peak level was 317 +/- 101 microU/L in angina patients, 2510 +/- 433 microU/L in infarcted patients and 62.3 +/- 17 microU/L in the controls. In both groups, the increase in serum myosin was more marked in those with larger infarction and in those with more severe angina. These data suggest that the measurement of serum myosin can identify the presence of micronecrosis in patients with unstable angina, according to what has been found using other markers of myocellular necrosis.


[The emergency treatment of supraventricular tachyarrhythmias: the efficacy and safety of intravenous propafenone].

One hundred patients, admitted to the Emergency Unit for paroxysmal supraventricular tachycardia (SVT) with 1:1 AV conduction, atrial fibrillation (af) and flutter (AF) of recent onset (less than 72 hours) were treated with intravenous propafenone (P). The drug was administered at the dose of 70 mg over 5 min, repeated after 10 min if sinus rhythm (SR) was not restored and eventually followed by continuous infusion (0.35-0.50 mg/min) until conversion to SR or during the next 48 hours. Exclusion criteria were ventricular rate < 100/min, R-R intervals > 1 s, clinical signs of heart failure or asthma. Termination of SVT within 30 min was obtained in 94% of the patients, while reversion to SR occurred in 79% with af and in 55% with AF. For af and AF conversion was achieved within 30 min in 49% of overall responders (R), between 30 min and 6 hours in 27% and between 6 hours and 48 hours in 24%. The efficacy of P was significantly influenced by the duration of arrhythmia and left atrial size, measured by 2D-echocardiography. On the contrary, no difference was observed between R and non-R in mean age and in the percentage of primary or relapsing arrhythmias. Adverse effects were encountered in 7 patients: in 1 case worsened arrhythmia and in 6 patients, with long-lasting arrhythmias, congestive heart failure. Neither conduction disturbance nor extra-cardiac complications occurred. In conclusion, P provides effective and safe treatment for paroxysmal atrial tachyarrhythmias, so that it can be considered among the drugs of first choice even in non-intensive care units.


[Recurrent cardiac echinococcosis: a report of a case with multiple intrapericardial cysts].

A case of an isolated recurrent cardiac hydatidosis with multiple intrapericardial cysts is presented. The patient, who underwent 2 previous surgical resection of intramyocardial and pericardial hydatid cysts, presented with atypical chest pain. The ECG and the perfusion scintigraphy with 201-thallium showed a previous lateral myocardial infarction. The diagnosis of recurrent cardiac hydatidosis was made by two-dimensional echocardiography and computed tomography and was confirmed by clinical and biochemical findings.


[The correlation between the acidic composition of diacylglycerol and protein kinase C activation in cultures of rat cardiomyocytes].

We have studied the fatty acid composition of the diacylglycerol produced after different stimulation times with an alpha 1-agonist (phenylephrine) in cultures of beating neonatal rat cardiomyocytes, and we have related the acidic pattern to the time course of the translocation of protein kinase C from cytosol to the membrane, both in control cells and in cells grown in a medium supplemented with docosahexaenoic acid. Gas chromatography of the diacylglycerol produced after stimulation revealed significant differences between control cells and cells grown in the docosahexaenoic acid supplemented medium. In the control cells, in the early stimulation times, the higher protein kinase C activity was due to a higher relative molar content of arachidonic acid in the diacylglycerol; in the docosahexaenoic acid treated cells the lower but more persistent activation of the membrane-bound protein kinase C might be sustained by an enrichment of diacylglycerol with docosahexaenoic acid. The modification of the fatty acid composition of diacylglycerol can cause an alteration in the response of the cells to alpha 1-adrenoceptor stimulation.


[The inotropic and bathmotropic effects of beta stimulation: a study comparing dobutamine and dopamine on the guinea-pig papillary muscle in isotonic contraction].

The study was aimed at comparing the effects of dobutamine (dob) and dopamine (dop) on isotonic contraction and rhythmicity of isolated guinea-pig papillary muscles (in oxygenated Tyrode at 37 degrees C), by taking into account: 1) the rate of stimulation (50% above the diastolic threshold) at 5 fixed periods: (RR: 1600, 1200, 1000, 800 and 400 ms); 2) 7 log concentrations (logC) of the index amine (from 10(-9) to 10(-3) M). To this end, a dose-relation protocol which explored the effects of all 5 RR and 7 logC was designed and 15 adult female Guinea-pigs (250 to 350 g) were randomized to either the dob (n = 8) or the dop (n = 7) arm. This enabled a total of 525 sets of data to be analyzed: in 38 sets (7.2%) premature contractions (CP) were coded. CP were sustained (freq: > 3) in 25 of these latter 38 sets (4.8%). Compared to the basal state, the amplitude (AMP%) and the log of percent amplitude (logAMP%) and time to peak (TP%) changes of the isotonic (Gould transducer) twitch were calculated along with the log of this latter variable (logTP%). AMP%, log AMP%, TP% and logTP% were linearly correlated with logC at all RR. In the range 1600-400 RR, for both amines, significant linear correlations (magnitude of 0.15 > r < magnitude of 0.70, 0.001 > p < 0.022) were seen for plots of AMP%, logAMP% and TP%:steeper correlations were observed for dop. This was confirmed in multivariate analysis (BMDP-9R) whereby AMP%, logAMP%, TP%, logTP%, CP, and freqCP were dependent variables and coded variables were included to either define the type of treatment (dop versus dob) or logC. In these analyses, logC (t > 11) and dop (t > magnitude of 3) might be used to explain (0.28 > r2 < 0.42, 0.00001 > p < 0.0025) AMP% and logAMP%, meaning that a different inotropic (isotonic) efficacy exists between these 2 amines, at all logC. On the other hand, when CP and freqCP were coded, explanatory variables were AMP% and logAMP% (4.86 > t < 6.95, 0.06 > r2 < 0.09, p < 0.00001), but not the variable used to code the type of treatment (dob versus dop).(ABSTRACT TRUNCATED AT 400 WORDS)


[A 31P-NMR spectroscopic study of the changes in energy metabolism induced by cardiac ischemia and reperfusion in rats of different ages].

In order to investigate the energetic status of the aged heart during ischemia and reperfusion we perfused female Wistar rats 6, 12 and 24 month old. The hearts were subjected to 15 min of global total ischemia plus 30 min of reperfusion. NMR spectra were collected during the entire experimental period to have the in vivo monitoring of the changes in intracellular pH and intracellular ATP, PCr and Pi contents. In the first 8 min of ischemia the fall of pH was similar in the 3 groups of rats, while at the end of the ischemic period the young rat hearts showed an intracellular pH significantly lower than aged rat hearts. At the end of reperfusion, ATP and PCr contents appeared significantly higher in the adult and aged hearts as compared to the young. The Pi content, on the contrary, was significantly lower in aged than young rat hearts. We suggest that the hearts of adult and aged animals, at the end of reperfusion, showed larger energetic recovery, in our experimental conditions of brief ischemia, than young hearts.


[Ischemia and reperfusion: the production and release of malondialdehyde, oxypurines and nucleosides in the isolated rat heart].

Ischemia and reperfusion damage has been evaluated by determining the sum of adenine nucleotides, nucleosides, oxypurines and the concentration of malondialdehyde, ascorbic acid, lactate and pyruvate in the isolated rat heart subjected to global normothermic ischemia and subsequent reperfusion. In addition, the sum of oxypurines and nucleosides, and the concentration of malondialdehyde has been determined in the perfusate collected during the reperfusion. Data indicate that ischemia and reperfusion induce an oxidative stress to myocardial tissue (increase of tissue malondialdehyde and decrease of ascorbic acid, and release of malondialdehyde during reperfusion) that, due to the output of relevant amount of oxypurines (congruent to 6.7 mumol/g dry weight) and of nucleosides (congruent to 7.0 mumol/30/min/g dry weight), it is not even able to restore its energy metabolism after reperfusion.


[The effects due to reduced coronary inflow and hypoxemia during myocardial ischemia].

The events associated to myocardial ischemia result from 2 overlapping phenomena due to reduced blood flow (ischemia) and reduced O2 supply (hypoxemia). To distinguish these effects, 2 groups of isolated rat hearts were perfused through the aorta (Langendorff's method) with Krebs-Henseleit buffer, and were exposed for 20 min to hypoxemia or ischemia, matched in terms of the O2 supply (10% of baseline), with continuous monitoring of cardiac contractility, O2 uptake and lactate production. The developed pressure and the O2 uptake were similar in hypoxemic and ischemic hearts; heart rate, end-diastolic pressure and lactate production rate were higher in hypoxemia than in ischemia; the recovery from hypoxemia was less than that from ischemia, despite the same O2 supplies; treatment with superoxide dismutase and catalase, scavengers of the O2 derived free radicals, during hypoxemia, allowed hypoxemic hearts to recover as ischemic hearts. Therefore, the main determinant of the reperfusion injury is to be attributed to the low O2 supply rather than to the low coronary flow; part of the injury is due to free radicals; a substantial portion is mediated by the energy demand during the stress which was higher in hypoxemia than in ischemia.


[The enzymatic activity of adenosine metabolism in the rat heart. The effects of cardiac hypertrophy].

The transmural distribution of the adenosine metabolizing enzyme activities 5'nucleotidase (5'N) and adenosine deaminase (ADA) across the left ventricular wall was explored in rats with heart hypertrophy induced by aortocaval shunt (FAC), or coarctation of the abdominal aorta (S) or by tireotoxicosis (T). FAC caused largest heart hypertrophy with a very short latency (1 day: + 0%, 3.5 days: + 30%, 7 days: + 41%, 21 days: + 49%). A 30% increase in the left ventricle free wall was observed after 3.5, 14 or 28 days of treatment with FAC, T or S respectively. Different changes in enzyme levels and alteration of transmural distribution profiles were observed with the different types of heart hypertrophy. Level of 5'N was decreased with FAC, did not change with T and increased with S; levels of ADA were always increased. The pattern of the transmural distribution of 5'N was affected by S but not by T and FAC, whereas distribution of ADA was not affected by S and T and was altered by FAC transiently.


[Isoproterenol causes changes in the mitochondrial energy metabolism in the rat heart].

In this paper we report observations on kinetic and structural characteristics of mitochondrial ATP synthase of rat-heart after subcutaneous injection of isoproterenol. The results obtained indicate: a decrease of respiratory rate either in absence (state 4) or in presence (state 3) of oxidative phosphorylation; decrease of respiratory control ratio; decrease of ATP hydrolase activity in sonic submitochondrial particles; decrease of relative content of the catalytic subunit F1 with respect to the membrane sector F0. The data obtained are in favour of the hypothesis that isoproterenol causes structural and functional alterations of mitochondrial ATP synthase.


Expression of desmin cDNA in PtK2 cells results in assembly of desmin filaments from multiple sites throughout the cytoplasm.

The assembly of intermediate filaments into a cytoplasmic network was studied by microinjecting into the nuclei and cytoplasms of PtK2 cells, plasmids that contained a full length desmin cDNA and an RSV promoter. Immunofluorescence was used to monitor the expression of desmin and its integration into the cells' vimentin intermediate filament network. We found that the expressed desmin co-localized with filaments of vimentin just as it does with fluorescently labelled desmin is microinjected into the cytoplasm of PtK2 cells. As early as two hours after microinjection of the plasmids, small discrete dots and short fragments of desmin could be detected throughout the cytoplasm of the cells. This initial distribution of desmin was superimposed on the filamentous pattern of vimentin in the cells. At 8 hours after microinjection of the plasmids, some of the desmin was present in long filaments that were coincident with vimentin filaments. By 18 hours, most of the desmin was in a filamentous network co-localizing with vimentin. There was no indication that desmin assembly began in the perinuclear region and proceeded toward the cell periphery. In some cells, excessively high levels of desmin were expressed. In these cases, overexpression led to clumping of desmin filaments as well as to an accumulation of diffusely distributed desmin protein in the center of the cells. This effect was apparent at approximately 18 hours after introduction of the plasmid. The native vimentin filaments in such cells were also aggregated around the nucleus, co-localizing with desmin. The microtubule networks in all injected cells appeared normal; microtubules were extended in typical arrays out to the periphery of the cells.


Desmosome assembly in MDCK epithelial cells does not require the presence of functional microtubules.

Desmosomes, complex multisubunit structures that assemble at sites of cell-cell contact, are important components of the epithelial junctional complex. Desmosome assembly requires the coordinated interaction at the plasma membrane of at least 8 cytoplasmic and integral membrane proteins organized into two structurally and functionally distinct domains, the cytoplasmic plaque and membrane core. Previous studies (Pasdar et al., J. Cell Biol., 113:645-655) provided evidence that cytokeratin filaments and microtubules may regulate transfer and assembly of cytoplasmic plaque and membrane core proteins, respectively. To determine directly the role of microtubules in these processes, Madin-Darby canine kidney (MDCK) cells were treated with nocodazole or colchicine to disrupt the microtubular network. Biochemical analysis of the different components of the cytoplasmic plaque and membrane core domains revealed little or no effect of nocodazole or colchicine on the kinetics of synthesis, post-translational modifications, transfer of proteins to the plasma membrane or their metabolic stability in the presence or absence of cell-cell contact. Likewise, immunofluorescence analysis of desmosome formation demonstrated an apparently normal desmosome assembly in the presence of nocodazole or colchicine upon induction of cell-cell contact. These results indicate that an intact microtubular network is not necessary for the processing or transport of the desmosomal membrane core glycoproteins to the plasma membrane in the absence or presence of cell-cell contact. Furthermore, the integration of the cytoplasmic plaque and membrane core domains induced by cell-cell contact at the plasma membranes of adjacent cells does not require the presence of functional microtubules.


LC20 and kinetics of gizzard myosin subfragment-1: digestion with papain vs. S. aureus protease.

Previous reports have shown that papain-digested gizzard subfragment-1 (PAP-S1) has a cleaved regulatory light chain (LC20), and Vmax similar to phosphorylated heavy meromyosin (HMM) (Greene et al., Biochemistry 22:530-535, 1983; Sellers et al., J. Biol. Chem. 257:13880-13883, 1982; Umemoto et al., J. Biol. Chem. 264:1431-1436, 1989], while S. aureus protease-digested S-1 (SAP-S1) has intact LC20, but Vmax closer to that of unphosphorylated HMM [Ikebe and Hartshorne, 1985]. To determine whether intact LC20 inhibits ATPase activity for subfragment-1 (S1), we compared the kinetic properties and structures of unphosphorylated PAP-S1 and SAP-S1. SDS-PAGE showed that SAP-S1 had 68 and 24 KDa heavy chain and 20 and 17 KDa light chain components. PAP-S1 (15 minutes digestion at 20 degrees C) also had 68 and 17 KDa bands, but the single 24 KDa band (24HC) was replaced by a group of 22-24 KDa fragments and LC20 was cleaved to a 16 KDa fragment. At 13 mM ionic strength, both PAP-S1 and SAP-S1 had Vmax similar to phosphorylated HMM (1.1-1.5 s-1). SAP-S1 had the same KATPase as phosphorylated HMM (38 microM actin), but KATPase for PAP-S1 was 3-fold stronger (11 microM actin). Subsequent digestion of SAP-S1 with papain did not significantly change Vmax, but as LC20 and 24HC were cleaved, both KATPase and Kbinding strengthened 3- to 5-fold. Thus, intact LC20 did not inhibit, and cleavage of LC20 did not increase Vmax for S1. Rather, papain cleavage of LC20 and 24HC was associated with strengthened actin binding.


Tubulin dimer formation via the release of alpha- and beta-tubulin monomers from multimolecular complexes.

The functional subunit of microtubules is a heterodimer consisting of alpha- and beta-tubulin. An understanding of tubulin dimerization has been hampered because it has not proved possible to purify native tubulin monomers. To study the process whereby tubulin dimers are formed, we made use of tubulins synthesized by in vitro transcription and translation. We present evidence that the in vitro synthesis of different mouse alpha-tubulin isotypes involves a multimolecular complex. The synthesis of mouse beta-tubulin isotypes also involves the formation of multimolecular complexes, though different isotypes behave somewhat differently from one another. The properties of in vitro synthesized alpha- and beta-tubulin multimolecular complexes strongly suggest that they are intermediates in the biosynthesis of tubulin monomers. Upon release, these monomers can exchange with pre-existing tubulin heterodimers.


The effect of hemorrhagic shock on intestinal amino acid absorption in vivo.

Hemorrhagic shock causes a disproportionate decrease in portal blood flow which may adversely affect the barrier and absorptive functions of the intestine. The absorptive capacity of the small intestine was studied during shock induced by mild and severe hemorrhage in the rat by measurement of the uptake of a radiolabelled amino acid analog (aminoisobutyric acid: AIB). Hemorrhage resulted in a significant reduction in systemic blood pressure, portal blood flow, and the absorption of AIB from the small intestine. Resuscitation restored both blood pressure and portal blood flow. But a significant reduction in absorption of AIB persisted. This suggests that hemorrhage results in an inhibition of amino acid intestinal active transport which is not dependent on the mesenteric circulation. The reduced intestinal absorptive function has important implications for the route of administration of nutrition following hemorrhage and trauma.


Arterial norepinephrine changes in patients with septic shock.

Arterial, mixed venous (pulmonary arterial), and peripheral venous norepinephrine and epinephrine levels; hemodynamics; and blood lactate levels were measured in 28 patients with septic shock (16 men and 12 women). During hospital follow-up, 18 patients (64%) died of circulatory failure. There were no significant differences in hemodynamic parameters or initial blood lactate levels between survivors and nonsurvivors. Initial arterial, mixed venous, and peripheral venous norepinephrine levels were elevated above normal in both survivors and nonsurvivors. However, norepinephrine levels at all three sampling sites were significantly higher in nonsurvivors than in survivors. Arterial or mixed venous norepinephrine level was better than peripheral venous norepinephrine level in distinguishing survivors from nonsurvivors. In contrast, the differences in plasma epinephrine levels between survivors and nonsurvivors became significantly different only after 48 hr of follow-up. During 60 degrees head-up tilt, the increase in plasma norepinephrine level was significantly higher in survivors compared to non-survivors, suggesting a differential response in the sympathetic nervous system in the two groups of patients. These data suggest that measurement of arterial or mixed venous plasma norepinephrine levels may be a useful guide for assessing the clinical course of patients in septic shock. Moreover, the differences in the sympathetic nervous system response to a 60 degree tilt may predict a poor outcome in these patients.


In vitro plasma perfusion through adsorbents and plasma ultrafiltration to remove endotoxin and cytokines.

In vitro plasma perfusion experiments were performed using small columns containing either resin or charcoal adsorbents to assess the removal of cytokines and endotoxin. 125I-labelled tumor necrosis factor-alpha (TNF-alpha; 500 pg/ml) and interleukin-6 (IL-6; 10 ng/ml) were added individually to human plasma. Over 4 hr of perfusion, Amberlite XAD-7 resin removed 32.5% +/- 3.3% (n = 5) of the initial amount of TNF-alpha and 71.4% +/- 3.8% (n = 5) of the initial amount of IL-6. DHP-1 polyhema-coated activated charcoal removed 17.2% +/- 6.2% (n = 5) of TNF-alpha and 48.5% +/- 7.4% (n = 5) of IL-6. Preliminary experiments were performed with lipopolysaccharide (LPS; 100 ng/ml) and interleukin-1 alpha (IL-1 alpha; 500 pg/ml), which showed that, over 4 hr, Amberlite XAD-7 removed 10.3% of the initial LPS and 29.1% of IL-1 alpha, whereas DHP-1 charcoal removed 23.2% of the initial LPS and 65.3% of IL-1 alpha. In vitro plasma ultrafiltration with either polysulfone or polyacrylonitrile membranes, as used clinically in haemodialysis, was performed with recirculation of plasma containing LPS or TNF-alpha. Neither of the substances was filtered to a significant degree. In conclusion, direct removal of these inflammatory mediators from the circulation of patients with multiorgan failure due to fulminant hepatic failure or sepsis would be possible by perfusion of plasma through adsorbents but not by haemodialysis.


Lung innervation and the hemodynamic response to 7% sodium chloride in hypovolemic dogs.

A pulmonary vagal reflex triggered by passage of hypertonic saline through the pulmonary circulation has been proposed as one of the mechanisms by which hypertonic saline resuscitates dogs in hemorrhagic shock. Thirteen anesthetized dogs with denervated left lung lobes were subjected to a standard hemorrhage model to evaluate this purported reflex. We then infused 7% NaCl (4 ml/kg) into either the innervated (six dogs) or the denervated (seven dogs) pulmonary circulation. There were no differences in cardiac output, mean arterial pressure, right atrial pressure, heart rate, or peripheral vascular resistance between groups during a 1 hr period after 7% NaCl infusion. Changes in hematocrit, total plasma protein, and osmolality after 7% NaCl administration suggested that plasma volume expansion had occurred and was similar between groups. We conclude that a pulmonary reflex elicited by hypertonic saline does not contribute to the beneficial hemodynamic effects associated with administration of 7% NaCl during hemorrhagic shock.


Effects of continuous naloxone infusion in intestinal ischemia shock in the rat.

The effects of continuous naloxone infusion on the response to intestinal ischemia-reperfusion were studied in a rat model. Naloxone was given as a bolus injection (2 mg/kg bw) followed by a continuous infusion (4 mg/kg bw/h) starting before (-10 min) intestinal ischemia was applied (0-60 min) and continuing 2 h after reperfusion of the intestine. Blood pressure, acidosis and survival were determined. Saline-infused shocked rats and untreated shocked rats served as comparisons and non-shocked animals as controls. Blood pressure was slightly higher before and during the continuous naloxone infusion but did not differ after reperfusion in the three shock groups. Acidosis was less pronounced in naloxone compared to untreated shocked rats. Survival rates were significantly higher in naloxone-treated shocked rats compared to untreated shock and significantly lower in saline treated shocked rats compared to non-shocked controls. In conclusion a naloxone effect on acidosis and survival in shock after intestinal ischemia and reperfusion is possible.


Tolerance of the liver as measured by ketone body ratio and hepatocyte energy charge to 120 minutes acute venous congestion in dogs.

Although acute passive hepatic congestion (APHC) sometimes occurs in patients undergoing open heart surgery or liver transplantation, the effects and safety limits of APHC on hepatic energy status have yet to be investigated. The present study reports an APHC model in 11 dogs in comparison with a control in 9 dogs by clamping the throacic inferior vena cava with passive venovenous shunt (APHC group) and by clamping the same with an active shunt at a rate of 60 ml/min/kg (control group). We investigated the effects of 120-min APHC on hepatic energy status by assessing the changes in arterial ketone body ratio (KBR) and hepatic energy charge (EC). After induction of the APHC, portal vein pressure elevated significantly to almost three times the control level. KBR decreased significantly for 60 min as compared with that of the control, but gradually recovered thereafter, returning to the preclamping level after reversal. Although total hepatic blood flow after 60-min clamping was approximately 18% of the preclamping value, no significant differences in EC and KBR values were seen after 60-min clamping as compared with preclamping and the control. All dogs in both groups survived at least 1 week. In this experimental model, 120-min APHC had no long-term effects on hemodynamics and energy production in the liver.


Antishock and endothelial protective actions of a NO donor in mesenteric ischemia and reperfusion.

Splanchnic artery occlusion (SAO) of the celiac, superior mesenteric, and inferior mesenteric arteries for 2 hr, followed by a 2-hr reperfusion period in cats produces a severe form of circulatory shock characterized by endothelial dysfunction, increased lysosomal leakage, and severe hypotension resulting from release of proteases, oxygen-derived free radicals, and other humoral mediators into the circulation. Administration of 0.75 mg/kg/hr of C873754, a nitric oxide (NO) donor, 10 min prior to reperfusion, significantly attenuated the accumulation of plasma cathepsin D from 12 +/- 3 U/ml in the SAO + vehicle group to 5 +/- 1 U/ml (P < 0.05) in the C87-3754 treated SAO group. A similar attenuation of plasma myocardial depressant factor (MDF) activity was observed in the C87-3754 treated cats (P < 0.02). Administration of C87-3754 significantly increased short term (i.e., 2-hr) survival rate (P < 0.05, compared to the vehicle group). Moreover, C87-3754 attenuated the SAO shock induced decline in release of endothelium-derived relaxing factor (EDRF) from isolated superior mesenteric artery (SMA) rings stimulated by acetylcholine and A23187. Additionally, C87-3754 significantly decreased PMN adherence to the superior mesenteric venous endothelium in vitro. Thus, treatment with the NO donor, C87-3754 reduced the accumulation of humoral mediators into the plasma while significantly attenuating endothelial dysfunction and improving short term survival.


Septic focus localized by determination of arterio-venous difference in neopterin blood levels.

We describe a case of a 38-year-old female accident victim who was admitted to the trauma hospital with an ISS of 66. Successful emergency treatment (including amputation of the left leg) and 4 weeks of intensive care led to an overall improvement so that the patient was extubated on day 29. Throughout this period neopterin was measured routinely 3 times a week and correlated well with the clinical course. At the end of the fifth week massive lung impairment and all clinical signs of sepsis appeared. Neopterin values increased dramatically up to 200 nmol/L. However, no abnormal findings were revealed by X-ray, contrast fluoroscopy, or sonographic imaging. To examine the amputation site more closely, simultaneous determination of neopterin in samples from the vena and arteria femoralis was performed. We found a 50% higher level in the venous blood (300 vs. 200 nmol/L). This was regarded as evidence for a hidden focus. Immediate surgical intervention revealed an abscess, which proved to be Pseudomonas aeruginosa positive. After adequate treatment the patient recovered quickly. In this case neopterin was not only helpful in monitoring the septic episodes of the patient, but proved essential for the detection of a septic focus and the risk of explorative relaparotomy could be omitted.


Calcium transport by rat liver plasma membranes during sepsis.

The effects of sepsis on the ATP-dependent Ca2+ transport in rat liver plasma membranes were investigated. Sepsis was induced by cecal ligation and puncture (CLP). Control rats were sham-operated. The results show that the ATP-dependent Ca2+ transport by liver plasma membranes was not affected during early sepsis (9 hr after CLP) but was decreased by 30-50% (P < 0.05) during late sepsis (18 hr after CLP). Kinetic analysis of the data indicates that during late sepsis, the Vmax values for ATP and for Ca2+ were decreased by 38.5% (P < 0.05) and 41.8% (P < 0.05), respectively, while the Km values for ATP and Ca2+ remained unchanged. Mg2+ stimulated ATP-dependent Ca2+ transport. The Mg(2+)-stimulated activity was unaffected during early sepsis but was decreased by 34-63% (P < 0.05) during late sepsis. These data demonstrate that ATP-dependent Ca2+ transport in rat liver plasma membranes was impaired during late sepsis and that the impairment is associated with a mechanism not affecting the affinity of the Ca2+ transporter for ATP and Ca2+. Since plasma membrane ATP-dependent Ca2+ transport plays an important role in the regulation of intracellular Ca2+ homeostasis in hepatocytes, an impairment in the ATP-dependent Ca2+ transport by liver plasma membranes during late sepsis may have a pathophysiological significance in contributing to the development of altered hepatic metabolism during septic shock.


Comparison of the pulmonary lymphatic and hemodynamic changes of near-drowning in a sheep model.

The hemodynamic and lung lymph changes following near-drowning (ND) were studied in sheep. Experimental ND was by transtracheal aspiration of 10 ml/kg body weight of either seawater (SW) or freshwater (FW). Extravascular lung water and lung lymph protein flux were significantly increased, but cardiac index was depressed in both groups following ND. Systemic and pulmonary vascular resistances were markedly elevated with FW compared to only a slight rise with SW. Lung lymph oncotic pressure decreased with SW ND from baseline of 9.7 +/- 0.4 to 6.8 +/- 0.63 mm Hg (P < 0.05). In contrast, FW ND increased lung lymph oncotic pressure from 12.8 +/- 0.9 to 16.6 +/- 1.3 mm Hg (P < 0.05). These data suggest that the changes in lung lymph and hemodynamic response to SW and FW ND differ in sheep. The changes are immediate and profound with SW, but slower in onset and less severe with FW. FW ND is associated with hemolysis, which is absent in SW ND.


Hyperdynamic sepsis in baboons: II. Relation of organ damage to severity of sepsis evaluated by a newly developed morphological scoring system.

The purpose of our study was to set up a baboon hyperdynamic sepsis model with live bacteria administration, which produces within 8 hr an organ failure comparable to human pathological conditions. Twelve adult male baboons were instrumented and studied for 8 hr under pentobarbital (2-3 mg/kg BW/hr) anesthesia breathing spontaneously. The animals were divided into two groups: 1) Live Escherichia coli were infused intravenously at a dose of 1.0-2.0 x 10(10) CFU/kg BW over 8 hr; 2) Live E. coli were infused i.v. at a dose of 5 x 10(8) CFU/kg BW over 2 hr. Organ damage was monitored by a newly developed scoring system. Organ damage was clearly dependent on the concentration of the bacterial challenge. Bacterial challenge at a dosage of 5.0 x 10(8) produces insignificant hemodynamic effects, while the 1.0-2.0 x 10(10) animals demonstrated massive hemodynamic alterations and needed much higher fluid support. The higher E. coli dosage was associated with an overwhelming organ damage seen, e.g., from the lung weight (12 g/kg BW vs. 9.6 g/kg BW with the lower dosage) or from the organ failure score, which is based on macroscopic pathology, histological data and organ weight. The percentage of animals with one, two, or three organ failures (organ failure score > or = 2) was higher in baboons with the higher dosage/kg BW. Therefore, we believe that the less severe organ damage in the acute phase after 8 hr with live bacteria 5 x 10(8) CFU/kg BW infusion over 2 hr is better to monitor the efficacy of newly developed therapeutic regimens, since in another set of experiments this model still produces lethal organ damage (80%) in a subchronic setting over 72 hr.


Two types of septic shock classified by the plasma levels of cytokines and endotoxin.

We investigated plasma levels of cytokines and endotoxin in septic shock to clarify the roles of various cytokines in this type of shock. Endotoxemia was observed in 16 of 22 septic shock patients. Plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin 1 beta (IL-1 beta) IL-2, and IL-6 were significantly higher in septic shock than in sepsis without shock. Strong correlations were noted between TNF-alpha and IL-2 levels and between IL-1 beta and IL-6 levels. Patients with high TNF-alpha and IL-2 levels also showed endotoxemia. We defined two types of septic shock from these data, i.e., endotoxin+TNF-alpha + IL-2 shock and IL-beta + IL-6 shock. In the former type, high TNF-alpha and IL-2 levels were present before the onset of shock, and shock itself was associated with endotoxemia. The second type showed simultaneous elevation of IL-1 beta and IL-6 levels at the onset of septic shock, and endotoxin was detected in some of them. These results suggest that endotoxin and extremely high levels of TNF-alpha and IL-2, or the simultaneous elevation of IL-1 beta and IL-6, are related to the onset of septic shock.


The genetic program for preimplantation development.

This review summarizes information on accumulation profiles of individual gene transcripts in preimplantation development. Most of the information is from the mouse, but some data from other species are reviewed as well. The principal finding is that the transcription of most genes is not temporally linked with any of the three morphogenetic transitions (compaction, cavitation, and blastocoel expansion) that characterize this period. Most genes that are expressed during preimplantation development of the mouse are already being transcribed in the 4-cell stage, and some clearly begin as early as the 2-cell stage. Once activated, a gene continues to be transcribed at least into the blastocyst stage, resulting in continuous mRNA accumulation. Thus the pattern of gene transcription established at the time of genomic activation in the 2-cell stage is perpetuated into the blastocyst, with a few additions along the way. This information is interpreted in light of previous findings concerning the sensitivity of morphogenetic transitions to inhibition of gene expression. The lack of a clear relationship between the timing of expression of most genes and the schedule of morphogenesis leads one to conclude that temporal regulation is imposed downstream of transcription and translation. This conclusion is substantiated by a consideration of factors controlling the events of compaction.


Sequence and expression of IMP-L1, an ecdysone-inducible gene expressed during Drosophila imaginal disc morphogenesis.

Drosophila imaginal discs are induced by the steroid hormone 20-hydroxyecdysone to initiate morphogenesis leading to formation of the adult appendages and thoracic epidermis at the end of the third larval instar. Ecdysone-dependent transcriptional activation of a set of genes that encode imaginal disc transcripts found on membrane-bound polysomes precedes and may be responsible for some aspects of the cellular changes that mediate epithelial morphogenesis in this system. A 1.35 kb transcript from one of these genes, IMP-L1, is first observed in vivo at or just prior to pupariation, as ecdysone titers are peaking and beginning to decline. Expression is initiated in proximal areas of the antennal disc, later spreading to a more widespread but nonuniform distribution throughout other thoracic imaginal discs. IMP-L1 is not, however, expressed in other ecdysone target tissues such as salivary glands or fat body. The IMP-L1 gene encodes a novel protein product containing a signal peptide, a possible transmembrane domain, two highly charged domains and a proline rich C-terminal domain. We suggest that the delayed timing of expression of this secondary response gene is necessary for proper ordering of cellular events associated with disc morphogenesis.


Use of a yeast site-specific recombinase to generate embryonic mosaics in Drosophila.

An efficient method for generating embryonic mosaics using a yeast site-specific recombinase (FLP), under the control of a heat shock promoter, is described. FLP-recombinase can promote mitotic exchange between homologous chromosomes that contain FRT (FLP Recombination Target) sequences. To demonstrate the efficiency of FLP-recombinase to generate embryonic mosaics, clones of the recessive and cell autonomous mutation armadillo (arm), detected by their ability to differentiate ectopic denticles in the naked cuticle of each abdominal segment, have been induced. We have analyzed the parameters of FLP-recombinase induced embryonic mitotic recombination and have demonstrated that clones can be efficiently induced during the postblastoderm mitotic divisions. We discuss applications of this technique for the analyses of the roles of various mutations during embryonic patterning.


[Evaluation of digital subtraction arthrography on the diagnosis of temporomandibular joint dysfunction syndrome].

Digital subtraction arthrography of temporomandibular joint superior cavity (TMJSC-DSA) was performed for 70 cases with TMJ dysfunction syndrome. A comparative observation between the operative findings and the findings of TMJSC-DSA examination was carried out for 11 cases who underwent TMJ operation. The results showed that TMJSC-DSA could overcome the disadvantages of conventional arthrography and make exact diagnoses for the anterior displacement of the disc and the disc perforation.


[A study of the computer aid design for tooth arrangement of full denture].

This paper is to use the power function Simpson's integration formula and some other methods to describe the geometric form of the dentition and edentulous arch in accordance with the theories and principles of tooth arrangement in textbook. The matching equations of artificial dentition and edentulous arch form and size are developed by using the multivariable regression method to analyze and summarize the clinical experiences of prosthodontists. Based on the above facts, a computer program that can be used to aid the dentist to arrange the artificial teeth for full denture is developed with Quick Basic Language and realized them in PC miniprocessors.


[A method of cephalometric analysis].

In this paper, 220 children ranging from age 11 to 15 were selected. Each of them received a cephalometric roentgenographic examination. 153 cephalometric items from 13 types of methods which had been widely in use were studied through statistic analysis. By means of "t" test, several items which expressed little difference between the normal occlusion and the malocclusion were eliminated. By using of the cluster analysis we selected one item to represent the items which were with similar effect. Finally, 17 cephalometric items were pick out to provide references for clinical work.


[Cell morphometric analysis in oral submucous fibrosis, leukoplakia and squamous cell carcinoma].

The morphometry of the cells and the nuclei in the spinous cells of oral epithelium in 48 specimens were studied by interactive image analysis system (IBAS-II). Five groups, normal mucosa, oral submucous fibrosis (OSF), leukoplakia, epithelial dysplasia and squamous cell carcinoma, were included. The result showed a progressive reduction in the dimensions (area, perimeter, all kinds of diameter) of the cells from normal mucosa, through OSF, leukoplakia, dysplasia to carcinoma (P < 0.01), while the dimensions of the nuclei did not show significant differences among the groups (P > 0.05), except the minimum diameter, but the nuclear cytoplasmic ratio showed a progressive increase (P < 0.01). The shape factors (form factor [PE] and contour index [CI]) seemed to be less helpful in identification. It indicated that the decrease of cell area of the spinous cell could reflect a malignant progress, and nuclear cytoplasmic ratio might be an objective feature to distinguish carcinoma from other lesions. The result also suggested that the pathological grade of OSF is between normal mucosa and mild epithelial dysplasia.


[Clinical application of sclerosing agent injection in treating habitual dislocation of temporomandibular joint].

Based on the experimental study, small amount of sclerosing agent was injected to the site outside the joint and below the ridge of TMJ on 105 cases for the treatment of habitual dislocation of TMJ. All of the cases were followed-up for more than 2 years and it was found that the cure rate reached 89 percent, including one case who was followed-up for 19 years free from recurrence. This method is suggested as it is simple to perform and acceptable to the patients. It has to be mentioned, however, that this injection was not so effective for those with cerebrovascular disease associated with habitual dislocation of TMJ.


[Effects of Lycium barbarum L and Drynaria fortunei J Smith on in vitro attachment and growth of human gingival fibroblasts on root surfaces].

In this study, the effects of Lycium barbarum L and Drynarna fortunei J Smith on in vitro attachment and growth of human gingival fibroblasts to root surfaces were investigated. The results revealed that the above herbs at dose of 1.25 mg/ml could improve attachment and growth of fibroblast, on the planed diseased root surfaces to a certain extent. When exposed to Lycium brabrum L cells on the diseased root surfaces increased markedly in number, with more even distribution, better spread, and more exuberant growth. Drynaria fortunei J Smith was not as potent as Lycium brabarum L. The results suggest that the two drugs may improve the formation of new attachment of periodontal tissue.


[Analysis of two kinds of method in the treatment of mandibular fracture].

In this paper, 27 cases of mandibular fracture with displaced fragment were divided into experiment group fixed by plate following AO principles and control group fixed by IMF. Through postoperative evaluation separately at the first, second, third month by means of X-ray, occlusal analysis based on dental models before and after fracture, occlusal force recording in areas of molar, premolar, incisors, and investigation of mandibular movement function during mastication, the results show that: (1) Occlusal relationship is not as satisfied as considered previously when IMF is used to treat mandibular fracture. In some cases, the dental cusps of molar and premolar don't contact tightly in lingual side, the occlusal plane seem to be inclined bucco-lingually. (2) The use of DC plate or EDC plate can avoid long-time IMF and reduce its complications, allow early function of mandibular fracture and follow the principles of biomechanics of combining mobility with static. As long as exact operative procedures, better occlusion than the use of IMF can be achieved.


[Sagittal fracture of mandibular condyle (SFMC) of the children treated by occlusal pad].

We have observed two cases of fresh SFMC of the children treated by occlusal pads and one case of old SFMC not treated. According to the survey of the above two kinds of SFMC, we conclude that: (1) The degree of the fractured fragment of the children are smaller than that in the adult. The outcomes of the cases treated by occlusal pads are good. (2) The condyle will be malformed and adhered to the lateral tubercle of the mandibular fossa in the untreated case. (3) The principles of the treatment of fresh SFMC are to prevent secondary trauma of the joint, to let the residual part of the condyle remodelling under light pressure and to reduce distance between the fractured fragments. The occlusal pad can fulfil these requirements.


[A scanning electron microscopic study of surface layer changes in artificial carious enamel].

The present study was carried out to describe surface changes and development of pathways of caries in vitro by the scanning electron microscope. Results indicate that direct crystal dissolutions of the surface layer itself are prominent features and recrystallization phenomenon is present in different degrees. The dissolution was more severe in Tome's process pit, focal hole and opening of striae of Retzius, but less severe in inter-rod areas.


[Photoocclusion analysis for the reduction of occlusal table dimension of the pontics].

50 cases of mandibular dentitions with normal morphology and occlusion are analyzed by using photoocclusion. The occlusal surfaces of the molars are divided into four regions buccolingually. That are the buccal inclines and lingual inclines of the buccal and lingual cusps of the molars. The relationship of sigma epsilon value among these four regions is 3:5:2:0 respectively. This indicates that it is effective to get force reduction by adjusting the buccal incline of the pontic in fixed bridge restoration.


Bactericidal activity and postantibiotic effect of cefdinir (Cl 983, FK 482) against selected pathogens.

The bactericidal activity and the postantibiotic effect (PAE) of cefdinir (Cl 983, FK 482) (CDR), were determined against Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, Branhamella catarrhalis and Escherichia coli (5 strains each) in comparison to erythromycin (E), cotrimoxazole (SXT) and amoxicillin-clavulanic acid (AMC). Kinetic studies of kill showed that CDR was rapidly bactericidal at concentrations 2 and 4 times the minimum inhibitory concentration (MIC): a reduction of 99.9% in CFU values was observed after 6-8 h for many of the isolates tested. As expected, a PAE was observed when S. aureus was treated with CDR at MIC (range of individual values for 5 strains 0.8-1.5 h) and 4 x MIC (range 1.1-1.4 h). Moreover, CDR showed a significant PAE at both its MIC and 4 x MIC against S. pneumoniae (range 0.5-1.0 h and 0.9-1.1 h), H. influenzae (range 0.4-0.7 h and 0.4-0.8 h), B. catarrhalis (range 0.5-0.7 h and 0.65-0.95 h) and E. coli (range 0.5-0.6 h and 0.5-0.7 h). The good bactericidal activity and the significant PAE of CDR against Gram-positive and Gram-negative bacteria (including respiratory pathogens) are a promising indication for the clinical efficacy of this cephalosporin in several bacterial infections.


Evaluation of cefixime biliary disposition in the isolated perfused rabbit liver model and in humans.

Cefixime is a new orally effective third-generation cephalosporin. It inhibits a wide variety of Gram-positive and Gram-negative bacteria, especially most of the Enterobacteriaceae. Since extrarenal excretion processes have been reported to account for 60% of cefixime systemic clearance we have endeavoured to determine the place taken up by biliary excretion of unchanged cefixime in this pattern. We initially used the isolated perfused rabbit liver technique. Six perfusions were performed. Cefixime concentrations were measured by HPLC chromatography. After addition of a single 10-mg dose of cefixime to the circulating blood, biliary elimination of the drug proved to be very low, since only 0.28 +/- 0.15% of the dose was recovered during the 3-h perfusion period. The rate of cefixime biotransformation in the liver was found to be 16.2%. In contrast, the data obtained in humans highlight substantial biliary excretion of the drug. In six healthy volunteers submitted to duodenal aspiration and receiving a single 200-mg i.v. dose of cefixime, drug levels in duodenal fluid were at least fivefold greater than the simultaneous concentrations in serum. Biliary excretion of cefixime was further investigated in ten cholecystectomized patients provided with T-tube drainage: following a single 200 mg oral dose of cefixime, Cmax in bile reached 56.9 +/- 70 mg/l, that is about 25 times as high as Cmax in serum, 2.3 +/- 0.85 mg/l. Drug levels in choledochal bile proved to be sustained, since a concentration of 4.3 +/- 3.7 mg/ml was still observed 20 h after dosing.(ABSTRACT TRUNCATED AT 250 WORDS)


Comparison of the effects of midecamycin acetate and clarithromycin on gastrointestinal motility in man.

The gastrointestinal motor effects of the macrolide antibiotic, clarithromycin, were compared with those of midecamycin acetate. The method of investigation consisted of intraluminal pressure measurements in the gastric antrum and upper small intestine by means of a low compliance perfused catheter system. Six healthy volunteers participated in the single-blind, placebo-controlled study of both interdigestive and postprandial gastrointestinal motility. Clarithromycin was administered by mouth in a dose of 250 mg b.i.d.; midecamycin acetate was given in a dose of 600 mg b.i.d. The effect of midecamycin acetate on gastric antral and jejunal motility was not significantly different from that of placebo. This was true for both the interdigestive and the postprandial phases of gastrointestinal motility. Oral treatment with clarithromycin (250 mg, b.i.d.) resulted in a statistically significant increase in the postprandial number of antral contractions per hour as well as in the postprandial antral motility index, as compared to placebo.


The action of propionyl-L-carnitine on the vasal endothelium: increased t-PA synthesis and a decrease in the activity of PAI-1. A preliminary study.

In this study the authors attempted to restore the coagulative fibrinolytic homeostasis that is compromised in peripheral vascular disease. Eleven patients with arterial disease, eleven with venous disease and seven healthy volunteers underwent oral treatment using 3 g of propionyl-L-carnitine divided into thrice daily doses for a period of 20 days. (1 g t.i.d.). This quaternaria amine is able to correct tissue hypoxia by increasing ATP and energy production and has the capacity to prevent alterations in endothelial membrane permeability. The authors observed a significant increase of t-PA synthesis on the 10th day of therapy in the arterial disease and control groups. All three groups showed a significant increase in t-PA synthesis on the 20th day of therapy. A significant decrease in PAI-1 activity was observed on the 10th and on the 20th day of therapy in both the patient groups, but not in the control group. Although the exact pathological mechanisms of peripheral vascular disease are complex and in many aspects still unknown, it is now absolutely certain that there is a pathogenetic role of functional imbalances. An important part is played by the reduction in t-PA synthesis and the increase in PAI-1 activity, and the authors conclude that it is necessary to use pharmaceutical substances to restore proper equilibrium.


Controlled study on L-carnitine therapeutic efficacy in post-infarction.

A controlled study was carried out on 160 patients of both sexes (age between 39 and 86 years) discharged from the Cardiology Department of the Santa Chiara Hospital, Pisa, with a diagnosis of recent myocardial infarction. L-carnitine was randomly administered to 81 patients at an oral dose of g 4/die for 12 months, in addition to the pharmacological treatment generally used. For the whole period of 12 months, these patients showed, in comparison with the controls, an improvement in heart rate (p < 0.005), systolic arterial pressure (p < 0.005) and diastolic arterial pressure (NS); a decrease of anginal attacks (p < 0.005), of rhythm disorders (NS) and of clinical signs of impaired myocardial contractility (NS), and a clear improvement in the lipid pattern (p < 0.005). The above changes were accompanied by a lower mortality in the treated group (1.2%, p < 0.005), while in the control group there was a mortality of 12.5%. Furthermore, in the control group there was a definite prevalence of deaths caused by reinfarction and sudden death. On the basis of these results, it is concluded that L-carnitine represents an effective treatment in post-infarction ischaemic cardiopathy, since it can improve the clinical evolution of this pathological condition as well as the patient's quality of life and life expectancy.


The effect of preterm birth on brainstem, middle latency and cortical auditory evoked responses (BMC AERs).

Recent studies on the maturation of auditory brainstem evoked responses (ABRs) present conflicting results, whereas only sparse reports exist with respect to the maturation of middle latency auditory evoked responses (MLRs) and auditory cortical evoked responses (ACRs). The present study reports the effect of preterm birth on the maturation of auditory evoked responses in low risk preterm infants (27-34 weeks conceptional age). The ABRs indicate a consistent trend towards longer latencies for all individual ABR components and towards longer interpeak latencies in preterm infants. The MLR shows longer latencies for early component P0 in preterm infants. The ACRs show a remarkable difference between preterm and term infants. At 40 weeks CA the latencies of ACR components Na and P2 are significantly longer in term infants, whereas at 52 weeks CA the latencies of the same ACR components are shorter in term infants. The results support the hypothesis that retarded myelination of the central auditory pathway is partially responsible for differences found between preterm infants and term infants with respect to late ABR components and early MLR component P0. Furthermore, mild conductive hearing loss in preterm infants may also play its role. A more complex mechanism is implicated to account for the findings noted with respect to MLR component Na and ACR components Na and P2.


Neonatal cerebral ultrasound, neonatal neurology and perinatal conditions as predictors of neurodevelopmental outcome in very low birthweight infants.

To determine the assessments before discharge from the intensive care unit, that will predict outcome most accurately, a prospective longitudinal study in a cohort of 79 high risk VLBW children was conducted from birth to 3.6 years of age. Birthweight, gestational age, obstetrical and neonatal optimality, neonatal neurological examinations and neonatal cerebral ultrasound were studied in relation to outcome. The best predictor for outcome was a simple cerebral ultrasound classification according to the presence or absence of ventriculomegaly and intraparenchymal damage of any cause. Infants with normal neonatal cerebral scans or abnormal scans without ventriculomegaly almost invariably had a normal neurological outcome. In infants with cerebral lesions with ventriculomegaly the incidence of normal neurological outcome decreased to less than 50%. Intraparenchymal damage was associated with cerebral palsy as well as other (mental and sensori) handicaps in over 85% of the cases. Neonatal neurological examinations at preterm age had additional value in predicting neurological outcome especially in the group with ventriculomegaly. Neither birthweight, nor gestational age, obstetrical or neonatal optimality were independent variables in the prediction of outcome in high risk VLBW children at 3.6 years of age.


Neonatal blood pressure levels of preterm infants who did and did not develop chronic lung disease.

The aim of this study was to assess if, in the neonatal period, there were differences in the blood pressure (BP) level of infants who did and did not develop chronic lung disease. If such differences were demonstrated to exist, we also hoped to determine influencing factors. Forty infants, consecutively admitted to our unit and who remained there throughout the neonatal period were studied. Twenty infants, median gestational age 29 weeks (range 27-32), did not develop CLD (non-CLD group) and 20 infants, median gestational age 26 weeks (range 24-32), developed CLD. Systolic BP was assessed using a non-invasive Doppler technique on day one and subsequently at weekly intervals. After day one and throughout the neonatal period BP levels, corrected for birthweight, were higher in the CLD group compared to the non-CLD group, by a mean of 5 mmHg. There was no significant difference between the numbers of infants in each group receiving theophylline or pancuronium. Significantly more infants in the CLD group had an umbilical catheter inserted and their catheters remained in situ significantly longer, a median of 8 days compared to a median of one day in the non-CLD group. We conclude that even in the neonatal period infants who develop CLD may have a modest elevation of BP, this is associated with prolonged umbilical arterial catheterisation. Our results, however, suggest that significant hypertension in infants who develop CLD, occurs after the neonatal period.


A comparison of height, weight and head circumference of primary school children living in deprived and non-deprived circumstances.

Heights, weights and head circumferences were obtained from two groups of primary school children: 1016 children from throughout Oxfordshire, a rural county with few areas of deprivation, and 219 children from an economically deprived part of the city of Newcastle on Tyne. Compared to Tanner and Whitehouse standards, Oxfordshire children were significantly taller, but not heavier, while the Newcastle children were significantly shorter and markedly lighter. Mean head circumference values were lower in the Newcastle than the Oxfordshire children. Existing national growth standards are outdated when applied to children in acceptably advantaged circumstances while impoverished children still fall below these standard in a pattern suggestive of under nutrition.


Umbilical cord insertion: normal location in neonates.

The distances between the xyphoid appendix and the insertion point of the umbilical cord (XU) and between the xyphoid appendix and upper edge of the pubic symphysis (XP) were measured in 201 newborn infants. The mean ratio XU/XP was 0.62 (S.D. 0.044) with no differences between sexes nor correlations with weight or length. Ratios lying between 0.53 and 0.71 can be considered as within the normal range.


Doppler velocimetry in cerebral vessels of small for gestational age infants.

Using the duplex Doppler system, blood velocity was measured serially at two sites of the anterior cerebral artery (ACA) and in the middle cerebral artery (MCA) during the first 3 days of life, in eight term, small for gestational age (SGA) infants (birthweight, 2179 +/- 230 g; mean +/- S.D.), and 13 term, appropriate for gestational age (AGA) infants (3376 +/- 441 g). All infants in both groups had normal Apgar scores and none manifested signs of respiratory distress. At 1 h post partum, the average MCA mean velocity in the SGA group (25.8 +/- 6.9 cm/s) was higher than that in the AGA group (19.6 +/- 5.7 cm/s), whereas the average values of the two ACA sites did not differ between the groups. A significantly increased value of the average mean velocity as compared to the value at 4 h post partum was reached earlier in the AGA group at all three vessel sites. The pulsatility index (as defined by Gosling) was lower at all vessel sites up to 72 h in the SGA group. Pulse pressure was significantly lower in the SGA group due to increased diastolic blood pressure. We suggest the results imply a state of cerebral vasodilation in the SGA infants and a poor ability to respond with an increased perfusion in the frontal regions supplied by the ACA. Changes in blood pressure and cerebral haemodynamics appear to exist in SGA infants in the absence of postnatal hypoxia which might explain the vulnerability of the growth-retarded infant to perinatal hypoxia.


Impact of early growth delay on subsequent fetal growth and functional development: a study on diabetic pregnancy.

In the first trimester of type-1 diabetic pregnancy, the embryo and fetus are often smaller than normal (early growth delay). We examined the impact of early growth delay on subsequent growth (birth weight) and functional development near term (organizational level of fetal behavioral states) in 21 and 10 fetuses of diabetic women, respectively. There was no relationship between the degree of early growth delay and birth weight (centiles). Mean growth delay per fetus in early diabetic pregnancy was negatively correlated with the occurrence of no-coincidence between behavioral state parameters at 36 weeks (R = -0.59; P < 0.05). These results indicate that disorders occurring in early life may underlie abnormal functional development in later life, whereas (catch up) growth is mainly determined during the second half of pregnancy.


Essential fatty acid status during early human development.

Preliminary studies indicated that the EFA status of normal neonates is marginal, if not insufficient. Since a better knowledge of the physiology of maternal-fetal essential fatty acid transfer is relevant for nutritional recommendations during pregnancy, we investigated the course of the fetal EFA status during fetal development by analysing the absolute (micrograms/g dry fetal tissue) and relative (% of total fatty acids) fatty acid composition of phospholipids in human fetal tissue, (n = 40, gestational age 5-15.2 weeks). The total content of fatty acids (mg/g dry fetal tissue) increased with gestational age. The absolute amount of virtually all fatty acids increased with maturation. Linoleic acid (18:2n-6, LA), however, was an exception. A highly significant, negative correlation between gestational age and the relative amount of LA in fetal tissue was observed during this first trimester of pregnancy. Our results show that the fetal-maternal difference in linoleic acid content observed at birth, initiates early in pregnancy. Since the fetus completely depends on the mother for its EFA supply, the maternal EFA status was measured simultaneously by analysing the fatty acid composition of phospholipids, isolated from plasma and red blood cells. Significant positive correlations between maternal rbc and fetal tissue were found for the relative amounts of LA. Similar relationships were observed between maternal plasma and fetal tissue for the relative amounts of cervonic acid (22:6n-3), the most abundant essential fatty acid in brain and retina. The relation between maternal and fetal EFA in phospholipids is significantly more pronounced after 10 weeks of gestation than before. This might be connected with the increased importance of the placenta with respect to maternal-fetal fatty acid transfer after 10 weeks of gestation.


Failure of expression of the phenobarbital-induced enhancement of UDP-glycosyltransferases in native, sealed endoplasmic reticulum vesicles from rat liver.

Conflicting data have been published regarding the effects of phenobarbital treatment on bilirubin UDP-glucuronyltransferase activity in native liver microsomes. Recent evidence suggests that the bilirubin UDP-glycosyltransferase system faces the interior of microsomal vesicles, and that expression of its activities in sealed microsomes may be rate-limited by transport of UDP sugars across the membrane. These observations raise the possibility that the reported variability in the effects of phenobarbital may reflect differences in integrity of the membrane in microsomal preparations. We examined the effect of phenobarbital on bilirubin UDP-glucosyltransferase and the UDP-glucuronyltransferase activities towards bilirubin, 4-nitrophenol, and 1-naphthol using native rat liver microsomes with verified vesicle integrity. Phenobarbital-induced microsomes in which the membrane permeability barrier was eliminated by pretreatment with detergent displayed markedly higher UDP-glycosyltransferase activities towards all tested substrates compared with activities in similarly disrupted microsomes from untreated rats. In contrast, none of the transferase activities tested were significantly enhanced by phenobarbital treatment when the enzymic activities were assayed in sealed microsomes. Addition to the enzyme assay mixture of UDPGlcNAc, a presumed physiological activator of the UDP-glucuronyltransferases, failed to expose the enhanced UDP-glucuronyltransferase concentration in phenobarbital-induced sealed microsomes. Our findings are consistent with the idea that transport of UDP sugar across the membrane may be rate-limiting for expression of UDP-glycosyltransferase activities in sealed microsomes. Quantitative assessment of membrane integrity is an essential prerequisite in experiments designed to study the regulation of the microsomal UDP-glycosyltransferase system.


Hyperoxia elevates Cu,Zn-superoxide dismutase of endothelial cells as detected by a sensitive ELISA.

An enzyme-linked immunosorbent assay (ELISA) was developed for the measurement of bovine Cu,Zn-SOD. Accuracy of the ELISA and specificity of the antibody for cell-free extracts was established by: (1) measurement of antigen levels of bovine endothelial cell extracts reconstituted with pure antigen, and (2) immunoblotting with affinity purified antibody. The ELISA was highly sensitive and 0.05-0.10 ng of pure antigen could be accurately detected, which allowed the measurement of Cu,Zn-SOD in as few as 250 endothelial cells. With utilization of the ELISA for detection, DEAE-cellulose chromatography patterns of endothelial cell Cu,Zn-SOD overlapped those of pure bovine erythrocyte Cu,Zn-SOD. Exposure of cells in culture to 80% O2 for 48 h increased the relative abundance of the Cu,Zn-SOD as measured by the ELISA by 1.8-fold. Thus, endothelial cells in culture respond to hyperoxia by enhanced production of Cu,Zn-SOD protein. The ELISA developed in this study may be useful for assessing other factors that regulate cellular production of Cu,Zn-SOD.


Tissue-mediated regeneration of ascorbic acid: is the process enzymatic?

Ascorbic acid's function in animals is attributed in part to the ease with which it reduces potentially damaging components, such as reactive free radicals. After more than six decades of speculation and laboratory efforts, the mechanisms by which ascorbic acid is maintained in the useful, reduced state remain uncertain. Previous attempts to isolate the enzymes that reduce the partially and the fully oxidized metabolites of vitamin C are reviewed. Some speculation on why dehydroascorbate reductase (EC 1.8.5.1) has not been purified from animal tissues is presented.


A rapid and strong increase of plasminogen activator induced by experimental anaphylaxis in rabbits.

Anaphylactic shock was induced in rabbits by injecting bovine serum albumin (BSA) as an antigen. Measurements of the enzyme activities in the fibrinolytic system confirmed that a rapid and strong increase of plasminogen activator (PA) was induced during anaphylaxis. The euglobulin fibrinolytic activity (EFA) as estimated by the plasminogen-rich fibrin plate method rose significantly, peaking at 15 min after the BSA injection (when the arterial pressure was minimum). However, EFA was not detected by the plasminogen-poor fibrin plate method. The tissue-type PA (t-PA) activity using the natural substrate plasminogen increased significantly with a peak at 15 min. The amidolytic activity also simultaneously increased significantly using the t-PA substrate, H-D-Ile-Pro-Arg-pNA. The plasminogen activator inhibitor (PAI) activity remained at baseline levels until 30 min, but rose fourfold at 90 min. The main plasma fibrinolytic enzyme which increased in anaphylaxis was proved by zymography to be t-PA with a molecular weight (MW) of 69,000.


Characterization of ecto-nucleoside triphosphatase on A-431 human epidermoidal carcinoma cells.

Hydrolysis of extracellular ATP and other nucleoside phosphates by A-431 human epidermoidal carcinoma cells was studied. The hydrolysis of extracellular ATP by these cells required either Mg2+ or Ca2+, and either cation could be replaced by Co2+, Fe2+, or Mn2+. Nucleoside triphosphates (ATP, GTP, CTP, UTP, and dTTP), but not nucleoside diphosphates, were hydrolyzed by the cells with Km and Vmax values similar to those for ATP (0.9-1.1 mmol/l and 6-10 nmol Pi formed/10(6) cells, respectively). The hydrolysis of ATP was inhibited strongly by ATP-gamma S and AMPPNP, and weakly by AMPCPP and ADP-beta S, but not by AMPCPP or AMPCP. Since the hydrolysis of [gamma-32P]ATP was inhibited by all these nucleoside triphosphates, the binding site for ATP is presumed to be the same as that for the other nucleoside triphosphates. All these results indicate that ecto-ATPase activity associated with A-431 cells is due to ecto-nucleoside triphosphatase. The nucleotide specificity shown in the present study indicates that ecto-nucleoside triphosphatase associated with A-431 cells is a molecule different from P2-purinergic receptors which can be stimulated specifically with nucleoside phosphates like ATP, ADP, UTP, UDP, and GTP, but not by other nucleotides.


Effect of thyroid hormones on 5'-nucleotidase of isolated rat fat cells.

5'-Nucleotidase was measured in isolated fat cells from normal, hypothyroid and hyperthyroid rats. This was done to find out whether thyroid hormones had an effect on the production of adenosine by the fat cell. The results showed that 5'-nucleotidase is modified when the rats received injections of 3,3',5-triiodo-L-thyronine (T3). There was no change in the enzyme in hypothyroidism or when T3 was added to incubation of cells.


Retinal oxidation activity and biological role of human cytosolic aldehyde dehydrogenase.

The major cytosolic aldehyde dehydrogenase isozyme (ALDH1) exhibits strong activity for oxidation of retinal to retinoic acid, while the major mitochondrial ALDH2 and the stomach cytosolic ALDH3 have no such activity. The Km of ALDH1 for retinal is about 0.06 mumol/l at pH 7.5, and the catalytic efficiency (Vmax/Km) for retinal is about 600 times higher than that for acetaldehyde. Thus, ALDH1 can efficiently produce retinoic acid from retinal in tissues with low retinal concentrations (< 0.01 mumol/l). The gene for ALDH1 has hormone response elements. These findings suggest that the major physiological substrate of human ALDH1 is retinal, and that its primary biological role is generation of retinoic acid resulting in modulation of cell differentiation including hormone-mediated development.


Detection of creatine kinase isoenzymes as tumoral markers of rhabdomyosarcoma.

We analyzed the expression profile of isoenzymatic fractions of creatine phosphokinase (EC 2.7.3.2) isotypes MM, MB and BB in three cell lines derived from embryonic rhabdomyosarcomas and a normal counterpart cell line. Electrophoretic data showed that the BB fraction was consistently expressed de novo, in contrast with its counterpart in normal tissue. The BB fraction may serve as new tumoral marker for the diagnosis of rhabdomyosarcoma. In addition, the appearance of macrocreatine kinase type-1 in this type of neoplasm may serve to reinforce the diagnosis when rhabdomyosarcoma is suspected.


Characterization of acatalasemia detected in two Hungarian sisters.

Acatalasemia was detected in 2 sisters of a Hungarian family. The pedigree of the family showed hypocatalasemia in the children of the patients and in 1 of their brothers, while the other members of the family had normal blood catalase activity. The biochemical characterization (catalase activity, electrophoretic migration, isoelectric point and enzyme stability) of the blood as well as tissue catalase of the acatalasemic patients yielded a catalase form which did not differ from normal.


Platelet-activating factor (PAF-acether) formation in neonatal intestinal mucosa and in cultured intestinal epithelial cells.

We report the presence of platelet-activating factor (PAF-acether; 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) in small-intestinal and colonic mucosa of neonatal rats. The PAF-acether content was higher in the colon than in the small intestine, and was lower in the small intestine of 30-day-old animals than in 14-day-old animals. We also report that cultured intestinal epithelial cells (INT 407) produce PAF-acether when stimulated with the calcium ionophore A23187, and that homogenized INT 407 cells can degrade PAF-acether with the formation of lysoPAF-acether. These findings suggest that intestinal epithelial cells are able to produce and metabolize PAF-acether, a potent mediator of inflammation. The authors propose that this might contribute to the pathophysiology of inflammatory bowel disease.


Evaluation of antioxidant treatment with superoxide dismutase in rat liver transplantation after warm ischemia.

In order to investigate the effects of the exogenously administered radical scavenger superoxide dismutase (SOD) on the orthotopic liver graft, livers from male Wistar rats were transplanted after subjection to 40 min of warm ischemia and 30 min of storage at 4 degrees C. SOD was given at the onset of ischemia and before reperfusion as a supplement (6,000 IU) to the washout solutions. 30,000 IU were infused into the recipient. SOD reduced tissue levels of thiobarbituric acid-reacting substances at the end of ischemia (737 vs. 956 nmol/g; p < 0.01) and 60 min after the onset of reperfusion (629 vs. 947 nmol/g; p < 0.001) and preserved total adenine nucleotides after reperfusion (11.69 vs. 10.40 mumol/g; p < 0.01). Survival 2 weeks after transplantation was 18% (2/11) in the SOD group versus 10% (1/10; nonsignificant) in untreated animals. It is concluded that SOD protects the ischemically altered liver from radical mediated peroxidation and preserves hepatic energy stores upon reperfusion. However, in our model no major improvement in organ viability could by achieved.


Hepatic energy metabolism during hypothermic storage and reperfusion using different protecting solutions.

Effects of 5 cold storage solution on hepatic high energy phosphate metabolism and metabolic function were examined using the isolated perfused rat liver. University of Wisconsin (UW), Euro-Collins (EC), and 2 cardioplegic solutions, Bretschneider's HTK and St. Thomas Hospital solution, were studied for their protective capacity. Krebs-Henseleit bicarbonate buffer (KHB) was used to point out the effect of simple hypothermia. Liver ATP, total adenine nucleotides and energy charge losses were significantly lower during 21 h of storage in UW-preserved livers. Also, only UW-protected livers were able to complete regeneration of ATP and total adenine nucleotides after 1 h of reperfusion, whereas EC, HTK, St. Thomas and KHB stored livers only showed minimal regeneration. Concerning metabolic function, UW protected livers liberated significantly less LDH and sGOT as well in the 21-hour storage solution as into the perfusate under reperfusion conditions. This study demonstrates the capability of UW solution in liver preservation by its ability to maintain and restore high energy phosphates.


Effect of hyperbaric oxygen and surgery on experimental gas gangrene.

An experimental model of clostridial gas gangrene was developed in rats and the therapeutic value of surgical debridement alone versus a combination of surgery and hyperbaric oxygen (HBO) was assessed. The infection was produced by an intramuscular injection of Clostridium perfringens microorganisms. The mortality of untreated rats was 100%. The mortality of the rats treated only with surgery was 37.5% compared to 12.5% when HBO was added to the treatment protocol (p < 0.01). In the group treated with HBO and surgery 82.5% of the animals healed completely and were able to walk normally, whereas the corresponding figure in the rats treated with surgery alone was 12.5% (p < 0.001). In the present experimental setting HBO treatment was an important therapeutic adjunct to surgery reducing both mortality and morbidity.


Portal venous pressure following splenectomy in patients with portal hypertension of differing etiology.

To clarify the effect of splenomegaly on portal hemodynamics in patients with portal hypertension and esophageal varices, manometric studies were carried out before and after splenectomy during an operation for esophageal varices. The 118 patients evaluated retrospectively had underlying liver cirrhosis (LC) (62), idiopathic portal hypertension (IPH) (42), and extrahepatic portal occlusion (EHO) (14). The weight of the spleen did not differ significantly among the three diagnostic groups: 640 +/- 473.5 g for LC, 780 +/- 414.6 g for IPH, and 683 +/- 457.2 g for EHO. Before splenectomy, portal pressure was significantly elevated in the patients with EHO (410 +/- 85.2 mm H2O) as compared to either the LC or IPH groups (348 +/- 64.1 and 348 +/- 73.5 mm H2O). Following splenectomy the reduction of portal pressure was significantly greater in the EHO group (29 +/- 15.5%) than in either the LC (18 +/- 17.4%) or IPH (19 +/- 17.0%) groups. Each group was subdivided according to severity of splenomegaly: marked (spleen weight > or = 500 g) or slight (spleen weight < 500 g). Patients with LC and marked splenomegaly showed a reduction in liver function parameters as shown by the prolongation of indocyanine retention rate at 15 min as compared to those with slight splenomegaly. Though it is not statistically significant, the average portal pressure tended to be higher among those with marked splenomegaly.(ABSTRACT TRUNCATED AT 250 WORDS)


Comparative cell culture effects of shape memory metal (Nitinol), nickel and titanium: a biocompatibility estimation.

Nitinol is an equiatomic alloy of nickel and titanium which has been attracting increasing interest in the field of biomedical engineering. To quantify toxicity as a preliminary evaluation of biocompatibility, inhibition of mitosis in human fibroblasts in tissue cultures exposed to test materials is an accepted screening method, although a dose-effect relationship had never been investigated. In this experiment, the effect of an increasing dose exposure to Nitinol, nickel or titanium on human fibroblasts in cell cultures was tested in subgroups in comparison with a control group. The results showed that nickel induces a significant (p < or = 0.05) inhibition of mitosis in human fibroblasts, whereas no significant effects of this kind were found for titanium or Nitinol. According to the results of these studies, Nitinol is to be considered in this respect biocompatible and comparable to titanium, which would seem to justify application as a surgical implant.


[Chemical plaque control].

Most of the diseases with which dentists must deal with are related to microbial plaque and bacterial infection. The mechanical removal of supra- and subgingival plaque by the patient and by the dentist respectively, is time consuming and exacting, furthermore it is not one hundred per cent successful. There has been extensive search for many years for chemical agents that could supplement or even substitute mechanical plaque removal. Many chemical agents delivered in different ways were tested. Chemotherapeutics of various modes of action have to meet pharmacokinetic and biological requirements. Apparently the ideal anti-plaque agent is not yet available, so that they should be reserved for well defined clinical situations and short--or medium--term application.


[Covering of residual palatal defects by a combination of prostheses].

We carried out successful oral rehabilitation of a 17 year old female patient, who had a congenital cleft lip and palate. Having been operated on several times, she still had residual cleft on her palate. We used removable metal plate clipped to the cemented circular bridge to cover the communication. It is known that fixed prostodontics are more acceptable for patients, and cause less psychical difficulties, especially in cases of patients with congenital disorders, which have already caused psychical disturbances.


[The effect of surface etching on tensile strength].

The aim of this study was to investigate the effect of different partial size of corundum used by sand blasting on the surface roughness and on the tensile strength. The conclusions of the authors were as follows: 1. The maximum values of tensile strength were measured when 200-250 microns corundum was used. 2. The values of the R(a) and Rmax were grown proportionally with the grain of corundum, but it was not resulted in the same increase of the tensile strength. 3. After the tensile test the residue of the bonding agent on one surface of the test-piece pairs, always remained significantly higher, than on the other, but this phenomenon cannot be explained by the differences between R(a) and Rmax within the test-piece pairs.


Induction and prevention of type 1 diabetes mellitus by viruses.

Genetic factors and environmental factors are thought to be involved in the pathogenesis of insulin-dependent diabetes mellitus Type 1. Viruses, as one environmental factor, may act as primary injurious agents to beta cells or as triggering agents for autoimmunity. Some viruses such as EMC-D and Coxsackie B4 can induce Type 1 diabetes by infecting and destroying beta cells in genetically susceptible mice. In addition, certain species of monkey, such as Patas, show elevated blood glucose levels and depressed insulin secretion after infection with Coxsackie B4 virus. An occasional case of Type 1 diabetes mellitus appears to be associated with the infection of beta cells with Coxsackie B viruses. In addition, Coxsackie B4 virus may also generate viral antigen-specific cytotoxic T cells which may cross-react with a beta cell-specific autoantigen leading to autoimmune Type 1 diabetes. In the case of viral triggering of autoimmune Type 1 diabetes, certain viruses (eg, retrovirus in NOD mice and rubella virus in hamsters and humans) may alter a normally existing beta cell antigen into an immunogenic form or might induce a new antigen, leading to beta cell-specific autoimmune insulin dependent diabetes mellitus. In addition, other viruses (eg, Kilham's rat virus in DR-BB rats) could generate antigen-specific T effector cells which may cross-react with a beta cell-specific autoantigen. In contrast to the induction of diabetes, viruses can prevent the development of diabetes. Inoculation of DP-BB or NOD mice with lymphocytic choriomeningitis virus reduced the incidence of diabetes or prevented the disease by disordering particular lymphocyte subsets.(ABSTRACT TRUNCATED AT 250 WORDS)


[Is it possible to improve the teaching methods of physicians who instruct patients? Comparative analysis of the same courses given before and after teacher's training].

The goal of the present study is to compare the pedagogic involvement of two groups of doctors, both of which were in charge of teaching the same courses to diabetic patients. Important structural differences were-shown exit between the two series of courses. The first group of ten doctors (who not undergone any pedagogic training) applied either ex-catedra teaching methods or proceeded by systematically asking questions to the patients. These scholastic methods led to passive attitudes in their patients in listening and replies to a large number of questions. In the second group of ten doctors (who had undergone pedagogic training) learning practices and a stimulating didactic material were used which resulted in more diversified and more attractive responses in the participation of the patients. Providing improved didactic means on the behalf of the doctors is aimed at obtaining better knowledge from patients who have themselves to assume the self-management of their treatment.


Local oscillations of frog skeletal muscle sarcomeres induced by subthreshold concentration of caffeine.

Different intracellular processes are selectively controlled by a signalling system based on transient rises or oscillations of cytoplasmic calcium concentration, which transmit extracellular signals at subcellular level. When treated with a subthreshold concentration of caffeine, skeletal muscle cells provide a suitable preparation to study mechanisms which generate repetitive calcium transients. Based on optical diffraction measurements of local contractions of individual sarcomeres, we have shown substantial enhancement of spontaneous repetitive calcium release in the presence of subthreshold caffeine concentration. Calcium release propagates to neighbor calcium sources and forms slow contraction waves. A power spectra density analysis has revealed parameters of the time course of these events. However, substantial amounts of calcium released in sarcomeres are not synchronized.


Evaluation of a dipstick test for microalbuminuria in three different clinical settings, including the correlation with urinary albumin excretion rate.

A dipstick test for microalbuminuria was compared with urinary albumin excretion and urinary albumin concentration. Elevated urinary albumin excretion was defined as > 30 mg/24 h, elevated urinary albumin concentration in early morning urine as = > 20 mg/l and sticks = > 20 mg/l were considered positive. 1,071 samples with urinary albumin concentration 20-200 mg/l from 258 diabetic subjects were evaluated in three settings: I. 3 trained nurses testing samples from day-clinic diabetic patients. Sticks v.s. urinary albumin excretion sensitivity 86%, specificity 97%, predictive value of negative test 97%, correlation coefficient 0.79. Values for same setting but v.s. urinary albumin concentration were almost identical. II. 1 laboratory technician testing not-hospitalised diabetic patients: Sticks v.s. urinary albumin concentration: sensitivity 91%, specificity 85%, predictive value of negative test 95%, correlation coefficient 0.82. III. 58 general practitioners testing not-hospitalized diabetic patients: Sticks v.s. urinary albumin concentration: sensitivity 66%, specificity 92%, predictive value of negative test 83%, correlation coefficient 0.70. In the hands of trained nurses and laboratory technician the Micral-Test showed good correlation with urinary albumin excretion and urinary albumin concentration for day-clinic and not-hospitalized patients and can be recommended as a screening tool. General practitioners obtained a lower sensitivity probably due to lack of experience and incorrect handling of the sticks leading to systematical errors. Training in the use of the stick must be emphasized, since under such circumstances the results are satisfactory.


Force-frequency relations in hypertrophic heart muscle: a mathematical model for excitation-contraction coupling.

Static and dynamic chrono-inotropic responses were recorded from both normal and hypertrophic rat auricular myocardium. The slope of the static force-frequency relation for hypertrophic hearts was steeper than that for control hearts. Computer experiments were designed to study the cellular mechanisms underlying the changes in the force-frequency response associated with heart hypertrophy, with the aid of a mathematical model for excitation-contraction coupling in rat heart. A set of equations was derived which permitted to study the effects on the chronoinotropic relations of both the geometrical dimensions of cardiomyocytes and the sarcoplasmic reticulum, and of the variation in activity of mechanisms for Ca movements through the sarcolemma and the sarcoreticular membrane. A comparison of data obtained from simulated and real experiments suggested that the features characteristic of force-frequency relations for hypertrophic heart are a result of an enhanced volume of intracellular Ca-stores rather than of the total volume of the cardiomyocyte.


Temperature studies of glyceraldehyde-3-phosphate dehydrogenase binding to liposomes using fluorescence technique.

Interaction of rabbit muscle glyceraldehyde-3-phosphate dehydrogenase with negatively charged liposomes was investigated as a function of temperature. This interaction affects the temperature-dependent conformational transition in the enzyme and exerts stabilizing effect on the protein structure. It can be seen from the fluorescence quenching experiments that the accessibility of tryptophanyl residues and isoindol probe fluorophores (covalently bound with the protein amino groups) for a dynamic quencher, acrylamide, is altered upon binding. This accessibility represented by effective quenching constant (Keff) strongly depends on temperature for unmodified enzyme and for the enzyme adsorbed on liposomes, it is nearly constant over a wide range of temperatures.


On the correlation of myopia and intelligence.

A pleiotropic relationship between intelligence and myopia has been shown to exist. Large eyes (as measured by axial length) have been shown to lead to myopia, and large brains have been shown to be more intelligent. I hypothesized that the myopia/intelligence relationship could arise because a single genetically controlled mechanism affects both brain size and eye size. This hypothesis has testable implications.


Outcomes of weight-loss programs.

We examined the results of a stratified random sample of 50 weight-loss studies conducted in the 1980s for weight change, change in overweight percentage, and improvement in physical health during treatment and follow-up. The typical participant was a White, middle-class woman 48% over her average weight before treatment, who lost 12.8 lb during a 13-week treatment program and then regained 4.3 lb over the next 6.5 months. Treatment efficacy was not improved when only the most successful treatment conditions were examined or when the studies conducted at the end of the decade were compared with earlier studies. Only one study examined change in physical health during weight loss, and only one study showed that participants moved from clinical to nonclinical levels of obesity. In light of these results, we argue that treating obesity through dieting techniques may be a misdirected goal.


African-American and Puerto Rican drug use: personality, familial, and other environmental risk factors.

Using a family interactional theoretical framework giving primacy to the mutual attachment between parent and child, we examined the interrelationship of acculturation, ecological factors, family, personality, peers, and drug context domains with drug use in an inner city sample. We also assessed the extent to which family protective factors mitigated against risks for drug use from most of the other domains. The sample consisted of 695 African-American and 637 Puerto Rican 7th-10th graders who answered the questionnaire while listening to it on personal tape players in their classrooms. The results of hierarchical regression analyses sufficiently supported the hypothesized sequence of interrelationships in both ethnic groups to substantiate our developmental model of drug use. We also found protective buffers common to both ethnic groups and buffers specific to each group. The implications of the results for targets and timing of intervention in the path to drug use are discussed.


The "temporalis-inhibitory reflex" in post-lumbar puncture headache.

Nausea and rigidity of the neck muscles, typical symptoms of post-lumbar puncture syndrome (PPS), may also be found in patients suffering from chronic headache of the tension-type. A decreased duration of the late suppression period of temporal muscle activity indicating a central disturbance of pericranial muscle control, can be observed in these patients. We have studied the temporalis-inhibitory reflex in 47 neurological inpatients requiring lumbar puncture. There were no significant differences of latencies or durations of temporalis silent periods between patients with and without PPS before, and 48 h following, lumbar puncture.


Hemicrania continua and chronic paroxysmal hemicrania: a comparison of pupillometric findings.

Pupillometric studies were carried out in 9 patients with chronic paroxysmal hemicrania (CPH), in 10 patients with hemicrania continua (HC) and in age- and sex-matched controls (n = 12-17). Studies were carried out in the basal condition and after instillation of 2% tyramine, 1% OH-amphetamine, or 1% phenylephrine. The pupillary response to tyramine in HC was more marked than in controls on a percentage increase basis, but not so much when the increment is calculated in absolute values. In this series, there was no asymmetrical response (relative miosis on the symptomatic side) like in previous case reports. The pupil reaction was less in HC than in CPH after hydroxyamphetamine instillation and without any marked asymmetry. There was no definite evidence of supersensitivity to a directly acting sympathicomimetic agent, phenylephrine. No gross abnormalities as regard the sympathetic function in HC was thus observed. The asymmetry on tyramine testing differed in CPH and HC (most marked in HC). No major emphasis should probably be attached to this finding, since on testing with OH-amphetamine, a similar substance, this finding was not reproduced.