Cervical canal leakage after internal bleaching.

The effects that walking bleach procedures had on root canal filling leakage and the extent of dentinal penetration were studied. Forty teeth were divided into four groups: 1--GP, set sealer, no base; 2--GP, set sealer, 2-mm Cavit base; 3--GP, unset sealer, no base; and 4--GP, unset sealer, 2-mm Cavit base. All were bleached for 7 days, fresh bleach was added for another 7 days, then methylene blue dye was placed for 5 days. The extent of dye penetration apically along the root canal filling and through the dentinal tubules was evaluated. The results indicate that 2 mm of Cavit was sufficient to significantly reduce linear leakage and dentinal penetration. The Cavit should be placed to a level slightly coronal to the facial cementoenamel junction. Teeth with cemental defects demonstrated greater perpendicular dye penetration in the areas of the defects than those with intact cementum. The data from this study suggest the use of a base material over gutta-percha in clinical practice prior to internal walking bleach procedures.


Leaching of hydrogen peroxide from bleached bovine enamel.

Accurately weighed bovine enamel slabs were individually immersed in 2 ml of 35% hydrogen peroxide for 1, 3, 5, 30, or 60 min. A control group was obtained by individual immersion of bovine enamel slabs in 2 ml of saline for 60 min. All samples were washed, dried, acid-etched with 37% phosphoric acid for 60 s, then washed and dried again. Two milliliters of double-distilled water were used for individual sample leaching. Leaching was done for 1, 5, 10, 20 min, or 7 days for the experimental groups and for 7 days for the control group. The samples of one of the experimental groups were leached for a second time for 1 min. A total of 112 samples was used in this study. Hydrogen peroxide was spectrophotometrically identified and quantified in all leaching solutions based on the oxidation reaction of leuco-crystal violet buffer solution by hydrogen peroxide, a reaction catalyzed by horseradish peroxidase. The results revealed a significant difference in the quantity of leached peroxide between bleached samples (irrespective of the duration of leaching) and control, saline-treated ones. No difference was observed in the quantity of leached peroxide between releached samples and control, saline-treated ones. However, these were small, random, and numerically insignificant. Statistically significant differences were also noted among some of the experimental groups. They were thought to hold no clinical significance. The results suggested that upon immersion, the complete leaching of peroxide from bleached enamel occurs rapidly.


Effect of different endodontic treatment protocols on periodontal repair and root resorption of replanted dog teeth.

This study examined, histologically, the healing of intentionally damaged root surfaces of replanted teeth with either uninfected or infected root canals treated with short- and long-term calcium hydroxide. Thirty beagle dog incisors were randomly divided into four groups. In group 1, uninfected obturated incisors were extracted, the roots were longitudinally grooved and the teeth were replanted within 2 min. In group 2 the root canals were artificially infected followed by extraction, longitudinal grooving, and replantation as described in group 1. Fourteen days after replantation, the root canals were fully instrumented and medicated with intracanal calcium hydroxide. One week later the root canals were permanently obturated with gutta-percha and sealer. The teeth in group 3 were treated as described in group 2 but after 1 wk the calcium hydroxide dressing was repacked for the duration of the study. In group 4 (positive control) the teeth were treated as described in groups 2 and 3 but no endodontic treatment was performed. After 8 wk, sacrifice and histological preparation were carried out. In group 1 complete cemental repair was seen in all teeth. In groups 2 and 3, complete and incomplete cemental repair was seen in seven and two teeth, respectively. An ankylotic area was present in one tooth in group 3. None of the teeth in group 4 showed cemental repair. It was concluded that short- and long-term calcium hydroxide treatment resulted in similar healing patterns when endodontic treatment is initiated 14 days after replantation of teeth.


Endotoxin and gram-negative bacteria in the rat periapical lesions.

The purpose of this study was to measure the amount of endotoxin as well as to identify Gram-negative bacteria in experimental periapical lesions in rats. Molar pulps were exposed and infected and the amount of endotoxin in the periapical tissue of the right mandibular first molar was measured by Endospecy, while the colony number of Gram-negative bacteria was determined in the same region of the left mandibular first molar. In the control animals, the amount of endotoxin in the periapical tissues did not change at all during the experimental period, and no Gram-negative bacteria were isolated. In the experimental animals, the amount of endotoxin in the periapical tissues increased gradually from 1 to 70 days, and its level was significantly greater than that of control animals after 7 days. Gram-negative bacteria were isolated from the periapical tissues and their number gradually increased from 1 to 14 days (26 to 82%), but decreased at 21 days. It was approximately 60% from 28 to 70 days. The results of this study showed that the amount of endotoxin in the periapical tissues gradually increased with increasing time and that Gram-negative bacteria were isolated from the same region but did not increase in number concurrently with the increase in the amount of endotoxin.


Root canal configuration of the mandibular first premolar.

One hundred six human mandibular left and right first premolars, previously extracted due to nonrestorable caries, periodontal disease, or orthodontic reasons, were sectioned perpendicular to the long axis of the root starting at the cementoenamel junction. Three-millimeter sections were made with an ultrathin separating disc to the level of the anatomical apex. After 1 day in 5.25% NaOCl, each section was rinsed in phosphate-buffered saline, evaluated with a stereomicroscope, and photographed. The slides were projected and the shape of the canal, incidence of multiple canals, level of bifurcation, and any other variant anatomy were recorded. Seventy-six percent of the premolars demonstrated Type I canals and 24% contained Type IV. The shape of the canals was predominantly oval or round. An interesting finding was the number of C-shaped canals which were associated predominantly with Type IV canal systems. This occurred in 14% of the roots.


Incidence of interappointment emergency associated with endodontic therapy.

Endodontic interappointment emergency (EIE) occurs in a low incidence following treatment by qualified operators. The purpose of this study was to assess the incidence of EIE after treatment by undergraduate students and to examine its correlation with preoperative and operative parameters. Randomly selected 334 records were retrospectively surveyed for unscheduled emergency appointments following endodontic treatment by undergraduate students. Treatment included step-back canal preparation in multiple visits with formocresol interappointment dressing. The incidence of EIE was 4.2%, and unrelated to the patients' sex and age or to tooth location. It was significantly higher in nonvital than in vital teeth (p < 0.05), with the highest occurrence in nonvital teeth unassociated with periapical radiolucency. Clinically, EIE was associated with swelling in half of the cases. It is concluded that the incidence of EIE following treatment by undergraduate students is low and related to tooth vitality.


Modified endodontics for lengthy canals.

A review of the dental literature concerning lengths of maxillary cuspids and reports of cuspid gigantism are presented. Endodontic therapy in these cases requires variations and modifications in conventional therapy for successful treatment. A case report is presented which illustrates some of these treatment modifications.


Symmetrical pulp obliteration in mandibular first molars.

Pulp obliteration is an extremely rare morphological type of pulp calcification, with calcified material completely occupying the pulp chamber and root canal spaces. The etiology of pulp obliteration may be trauma or systemic diseases such as secondary hyperparathyroidism. Pulp obliteration may also be seen in dental anomalies such as dentinogenesis imperfecta and dentinal dysplasia. In cases of pulp obliteration with periapical disease, the preferred treatment is surgery, while calcified canals without symptoms or periapical lesions are best left untreated.


Using cyanoacrylate to facilitate rubber dam isolation of teeth.

Cyanoacrylate is an extremely strong bonding agent which has many applications in medicine. It is also effective in obtaining a leakproof seal of rubber dam around a structurally compromised tooth requiring endodontic therapy.


[Stability of dilute solutions of ganciclovir sodium (Cymevan) in polypropylene syringes and PVC perfusion bags].

The stability of ganciclovir sodium solutions stored in polypropylene syringes and PVC bags was tested in 0.9% sodium chloride at three concentrations 70, 200 and 350 mg/50 ml for polypropylene syringes, and two concentrations (70 and 350 mg/250 ml) for PVC bags and at three temperatures (-20 degrees C, + 4 degrees C, room temperature). The solutions, which had been initially frozen, were thawed by exposure to microwave radiations. The stability of each sample was determined by high-performance liquid chromatography. The results of this study indicate that admixtures of ganciclovir sodium at the concentration rates tested can be frozen for at least one year and are stable for at least 80 days at + 4 degrees C and 7 days at room temperature.


Disulfide bond cleavage of human fibrinogen by cis-diamminedichloroplatinum(II).

Disulfide bridges in fibrinogen (Fbg) were cleaved by cis-diamminedichloroplatinum(II) (cis-DDP). Incubation with 120 molar excess of cis-DDP at pH 7.4 and 37 degrees C in the presence of EDTA resulted in cleavage of seven disulfide bridges out of 29. In the presence of calcium, however, the number of cleavages were reduced to four. The result indicates that calcium, which has three high affinity sites on Fbg, protects disulfide bridges from the rupture. Thrombin clottability was examined by turbidity measurement. The cis-DDP treated Fbg was shown to give a decreased fiber thickness. As the cleavage proceeded, the clotting ability of Fbg decreased.


Flow cytometry to evaluate the parasitemia of Plasmodium falciparum.

The resistance of plasmodiums to the current antimalarial agents has spurred the search for new active molecules of vegetal origin or chemical synthesis. The screening of antimalarial molecules "in vitro" was done by simple but tedious techniques such as quantification of parasitemia through optical microscopy or by using radioactive markers. We have developed a new method to evaluate parasitemia by using the ODAM ATC 3000 flow cytometer and biological cell sorter. We selected the ethidium bromide for labelling the nucleic acids of Plasmodium falciparum, and we optimised the method by using a mathematical model: the design of Hadamar. This simple technique presents the advantage of being an objective and rapid count of large number of red cells (10(6) x 10(7)). This method is rapid, reliable, reproducible, devoid of subjectivity and provides more precise results than those of optical microscopy. The good correlation between paraitemia measured by optical microscopy and fluorescence obtained by flow cytometry allows us to recommend this technic for the screening of new antimalarial molecules.


Cytokine-related immunopotentiating activities of paramylon, a beta-(1-->3)-D-glucan from Euglena gracilis.

Paramylon, a beta-(1-->3)-D-glucan, isolated from Euglena gracilis, was tested for its adjuvant activity on the antibody response to sheep red blood cell (SRBC) in mice. Paramylon markedly enhanced anti-SRBC plaque-forming cell production at a dose of 10 mg/kg. It was also found that in vitro addition of lipopolysaccharide in culture to macrophages from paramylon-treated mice produced a large amount of interleukin 1 (IL-1) and there was a significant level of interleukin 6 (IL-6) induced transiently in the blood of these mice. As IL-1 and IL-6 play crucial roles in the immune response to T cell-dependent antigens like SRBC, the immunopotentiating effect of paramylon might be expressed through the action of these cytokines.


[Freezing of solutions for parenteral usage: advantages and disadvantages. Nine month's experience at the pharmacy of the Hospital of Nancy].

Usually parenteral solutions can be kept longer if they are frozen. This freezing procedure assumes one knows the stability of frozen drugs. Freezing has a few drawbacks; preparations must be labelled twice (before and after freezing), only standardized doses can be prepared, thawing procedures must be established, cost of freezer and microwave-oven and time needed for thawing and labelling. There are four main advantages; production plannings are improved because time needed for preparation is reduced, quality assurance of the preparation, availability of preparation at any time, reduce of drug wastage. Freezable drugs are listed and sorted by pharmacological class. The presentation includes drug concentration, vehicle, container, storage temperature, assay procedure and stability. Our nine months experience is presented. Three drugs are frozen; methotrexate, metoclopramide and ganciclovir. Considerable preparation time is saved and economy is about FF 150,000.


Comparison of the effects of halothane and propranolol on the effective refractory period and the ventricular activation in a canine myocardial infarction model.

The effects of halothane on the effective refractory period (ERP) and the ventricular activation were examined in a canine myocardial infarction model, and compared with those of propranolol. Halothane reduced the heart rate and prolonged the ERP in both normal and infarcted zones. A prolongation of ERP with halothane was also observed during atrial pacing at the same rate as in control, but the effect was less than during sinus rhythm. Halothane (1 MAC) further delayed or blocked the delayed activation in the infarcted zones with only slight effects on the activation of the normal zones. Propranolol (0.2 mg/kg) prolonged ERP during sinus rhythm, but it did not affect either the ERP or ventricular activation during atrial pacing. In conclusion, halothane produced a selective depression of the delayed activation and the prolongation of ERP, which may be caused by both direct effects on the myocardium and secondary effects such as a reduction of the heart rate. These effects of halothane may contribute to its antiarrhythmic effects in the myocardial infarction model which have been previously reported.


[Clinical formulations of amphotericin B].

The clinical use of amphotericin B is impaired by its poor water solubility and by the severity of its side effects. Several amphotericin B formulations have already been prepared in an attempt to overcome these disadvantages. The following methods have been proposed to solubilize amphotericin B in water: the complexation of amphotericin B with metallic ions, sodium tetraborate or gamma cyclodextrin or the synthesis of semi-synthetic derivatives. Another approach was to use a carrier (liposomes, lipoproteins, emulsions or surfactants) to target amphotericin B. This paper summarizes and criticizes these formulations.


Pharmacokinetic interaction of zonisamide in rats. Effect of other antiepileptics on zonisamide.

The pharmacokinetics of zonisamide (ZNS) and the effects of phenobarbital (PB), valproic acid (VPA), carbamazepine (CBZ) and phenytoin (PHT) on ZNS kinetics were investigated in rats. The effects of other antiepileptics on the serum protein binding, erythrocyte distribution and metabolism of ZNS were also studied in vitro to elucidate the mechanism of pharmacokinetic interaction of ZNS. ZNS showed a linear disposition kinetics after oral administration of ZNS within the dose examined. Moreover, the pharmacokinetic behaviors of ZNS were not altered after multiple dosing. The decreased t1/2 value of ZNS by PB or CBZ pretreatment and the increased Vd/F value of ZNS by VPA pretreatment were observed, although it showed no marked effect of PHT on ZNS kinetics. The enhanced metabolism of ZNS was observed by PB or CBZ pretreatment from an in vitro metabolism study. The serum protein binding and erythrocyte distribution of ZNS showed no significant change in the presence of other antiepileptics in vitro. These results indicate that the decreased t1/2 value of ZNS is attributable to the enzyme inducing effect of PB or CBZ, and that neither protein binding nor erythrocyte distribution of ZNS could be the reason for the increased Vd/F value of ZNS by VPA coadministration.


Pharmacological studies on 3-formylamino-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-one (T-614), a novel antiinflammatory agent. 3rd communication: the involvement of bradykinin in its analgesic actions.

In order to elucidate the analgesic mechanism of 3-formylamino-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-on e (T-614), its effects on the kinin-forming system were examined both in vivo and in vitro. T-614, at doses more than 10 mg/kg p.o., exhibited a significant inhibitory effect on the increased levels of bradykinin released into the pouch fluid of kaolin-induced inflammation in rats. In the kaolin-induced writhing response in mice, which is shown to be mainly dependent on the action of bradykinin, T-614 reduced not only the writhing frequency but also the peritoneal levels of bradykinin in a dose-dependent manner. Whereas, in the zymosan-induced writhing response in which prostaglandin I2 (PGI2) is shown to be an important mediator, it did not exert an obvious inhibition on either writhing responses or peritoneal PGI2 levels at a highest dose of 100 mg/kg. T-614 did not inhibit the activities of serine proteases, such as trypsin, thrombin, kallikrein and plasmin. Furthermore, it did not affect the kinin-forming enzymes of rat plasma in vitro. The above results suggest that the analgesic effects of T-614 may be partly mediated by the inhibition of bradykinin release in the local inflamed tissue.


Pharmacological studies on 3-formylamino-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-one (T-614), a novel antiinflammatory agent. 4th communication: inhibitory effect on the production of interleukin-1 and interleukin-6.

In vitro effects of 3-formylamino-7-methylsulfonylamino-6-phenoxy-4H-1-benzopyran-4-on e (T-614), a novel antiinflammatory compound, on the production of interleukin-1 (IL-1) and/or interleukin-6 (IL-6) by human monocytes and the THP-1 cells of a human monocytic cell line, were examined. T-614 inhibited the release of immunoreactive IL-1 beta from these cells stimulated with lipopolysaccharides (LPS) in a dose-dependent manner (0.3-30 micrograms/ml). The release of IL-6 from THP-1 cells, as determined by the assays for its hepatocyte-stimulating activities and immunoreactivities, was inhibited by T-614 with the IC50 values of 2.0 and 6.6 micrograms/ml, respectively. Northern blotting analysis using LPS-stimulated THP-1 cells indicated that the inhibitory effect of T-614 on IL-1 beta production is caused by the suppression of IL-1 beta mRNA expression. The inhibition of cytokine production by T-614 may provide an important insight into the additional mechanisms contributing to its antiinflammatory activities.


Effects of long-term administration of (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-ethoxycarbonyl-3- phenylpropyl)amino]propionyl]-2-oxoimidazolidine-4-carboxylic acid hydrochloride (TA-6366), a new angiotensin I converting enzyme (ACE) inhibitor, from the pre-hypertensive stage on morphological change and mechanical property related to sodium ion permeability in aorta of spontaneously hypertensive rats (SHRs).

Effects of (4S)-1-methyl-3-[(2S)-2-[N-((1S)-1-ethoxycarbonyl-3-phenylpropyl)amino]- propionyl]-2-oxoimidazolidine-4-carboxylic acid hydrochloride (TA-6366) on morphological change and mechanical property related to sodium ion permeability in the aorta of spontaneously hypertensive rats (SHRs) were examined, as compared with those of enalapril and captopril. Ten-week oral administration of TA-6366 (1 and 5 mg/kg/d) from 4 weeks of age impeded aortic media-thickening together with a rise in blood pressure in SHRs. Concomitantly, aorta weights in both groups were markedly decreased. The higher dose of TA-6366 almost fully suppressed the accelerated tension development induced by K(+)-free medium and decreased total sodium ion content in the aorta. These vascular effects of TA-6366 was more prominent than those of enalapril and captopril at 5 mg/kg/d. The difference in potencies on the above vascular parameters between TA-6366 and these drugs seemed to be mainly related to the difference in their antihypertensive activities. These results suggest that TA-6366 has preventive effects against progression of vascular diseases, particularly atherosclerosis, accompanied with hypertension.


Sex roles in management: the impact of varying power of speech style on union members' perception of satisfaction and effectiveness.

Effective management has traditionally been associated with men and masculine characteristics. In this study, I focused on manager communication, specifically the perceived effects of stereotypical gender/power speech styles. Union members viewed and rated a male and a female manager on videotape using three gender/power speech styles: stereotypical masculine (powerful), stereotypical feminine (powerless), and mixed gender/power. Union respondents judged both the male and female manager using the mixed gender/power speech style as most effective and as being associated with the most satisfied employees.


Factors affecting reactions to a rape victim.

We examined the influence of the sex of the subject reacting to the rape victim, the type of rape (stranger vs. acquaintance), the location of the rape (inside vs. outside the victim's home), and the victim's attribution concerning the cause of the rape, on undergraduates' reactions to a rape victim. American undergraduates (264 women, 230 men) read a Rape Crisis Center Intake Form, watched a videotape of a rape victim (an actress) describing her psychological and behavioral reactions to the rape, and completed three questionnaires assessing their reactions to the victim. Women were more supportive of the rape victim than were men, and the stranger rape evoked more chance and characterological attributions than did the acquaintance rape. A rape outside the home evoked more chance attributions than did an "inside" rape. The rape victim was rated as having been more traumatized by the experience if she made any causal attribution than if she made no attribution at all.


Development and psychometric evaluation of the Primary Appraisal of Smoking Cessation Inventory.

For this study, we developed and evaluated the psychometric properties of the Primary Appraisal of Smoking Cessation Inventory (PASCI), a self-report measure designed to assess the perceived gains and losses associated with quitting smoking based on the theoretical model of stress described by Lazarus and Folkman (1984). We administered the 26-item PASCI and two other questionnaires to 244 current smokers and to 30 ex-smokers. Item analyses indicated that two items on the PASCI should be deleted due to low item-total correlations. A principal components analysis of the remaining 24 items identified two separate and independent factors, Losses and Gains, and scores on the subscales of both factors were internally consistent and stable over repeated administrations. The validity of the PASCI was established by examining the relationship between smoking status and scores on the PASCI subscales and by finding significant correlations between the PASCI and the Decisional Balance Scale (Velicer, DiClemente, Prochaska, & Brandenburg, 1985), a measure conceptually similar to the construct measured by the PASCI. We concluded that the PASCI is reliable and valid and can be used to investigate the relationship between primary appraisal and smoking cessation.


Nature of romantic love in female adolescents.

In the present study, I intended to determine the similarity between Rubin's (1970) Love Scale components and five of Lee's (1976) six lovestyles in a relatively homogenous sample of 301 16- and 17-year-old British females. Items describing loving behaviors toward a particular individual were formulated to measure these lovestyles together with that of Ludus. The six orthogonal factors extracted from the correlation matrix of these and Rubin's items were called Love, Mutual Love, Respect, Similarity, Physical Attraction and Hostility. The results suggested that Rubin's Love Scale contained elements of Mania and Agape but none of Ludus, which could not be further differentiated. Rubin's (1970) Liking Scale, however, could be further subdivided into Respect (Pragma) and Similarity (Storge).


Left ventricular mass regression in elderly hypertensives.

It is now recognized that left ventricular hypertrophy (LVH), often associated with hypertension, is itself a risk factor for coronary disease in the elderly. Although many agents are capable of controlling blood pressure, the ability of these agents to induce regression of left ventricular (LV) mass, and the effect of regression on diastolic relaxation and contractile indices in the elderly are less well known. Our study compared the ability of the calcium blocker, verapamil, and the beta-blocker, atenolol, to both control blood pressure (BP) and to induce regression of LV mass in older hypertensives. In addition, the influence of regression on resting diastolic filling and on cardiac output and ejection fraction during rest and mild upright bicycle exercise were determined. Forty-two hypertensives 60 years of age or above, without evidence of ischemic disease underwent 2-D echocardiographic evaluation of LV mass and gated blood pool scan determination of early diastolic filling, cardiac output and ejection fraction. They were then randomized to receive verapamil or atenolol during a four-week titration period so as to achieve a BP of less than 160/90 mm Hg. If BP was not controlled with either agent, chlorthalidone was added. Individuals whose BP was controlled continued on the protocol for six months. At that time, the echocardiographic and gated blood pool studies were repeated both on and after subsequent withdrawal of the study medications. Twenty-one patients were randomized to receive verapamil and 21 patients to receive atenolol. Blood pressure control was achieved with verapamil alone in 18 patients, but with atenolol alone in only 8 patients (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)


Combination therapy in hypertension.

In patients in whom monotherapy does not control blood pressure a second agent is required. Common combinations in clinical practice are a beta-blocker plus a diuretic, an angiotensin converting enzyme (ACE) inhibitor plus a diuretic, a beta-blocker plus a dihydropyridine calcium antagonist, and an ACE inhibitor plus a calcium antagonist. Since both ACE inhibitors and calcium antagonists are metabolically inert and exert favorable effects on target organ disease, their combination is of particular interest. When combined, these two drug classes have additive effects on antihypertensive efficacy, reduction of left ventricular hypertrophy, and protection of the renal circulation. However, whether or not these favorable pathophysiologic changes induced with combination therapy of ACE inhibitors and calcium antagonists will translate into a reduction of morbidity and mortality remains to be documented.


Antihypertensive therapy in diabetic patients.

Diabetes mellitus (DM)-linked metabolic alterations and hypertension concomitantly accelerate or precipitate cerebrovascular and coronary heart disease, nephropathy, retinopathy and widespread macroangiopathy, thereby conferring to diabetic patients a very high risk of morbidity, disability and early death. Therefore, the long-term care for diabetic patients should be aimed at concomitant metabolic and blood pressure (BP) control. Dietary measures are indispensable; a high fibre, low fat, low salt diet is recommended, complemented with caloric restriction and physical exercise when body weight is above the ideal. Antidiabetic pharmacotherapy involves an unresolved dilemma. The desired achievement of euglycemia necessitates effective levels of insulin, but hyperinsulinemia (due to parenteral [over]treatment in insulin-dependent DM) is suspected to promote atherogenesis and represents a coronary risk factor and perhaps even facilitates hypertension. Considering antihypertensive pharmacotherapy, thiazide-type or loop diuretics are problematic drugs in DM because they can aggravate metabolic alterations. These agents also seem to exert only a limited preventive or regressive effect on left ventricular hypertrophy (LVH); beta-blockers are also not considered ideal, since they decrease the awareness of hypoglycemia and tend to promote glucose intolerance. Unselective beta-blockers in particular promote peripheral ischemia and insulin-induced hypoglycemia, while beta-blockers without intrinsic sympathomimetic activity lower serum HDL-cholesterol. Calcium antagonists and ACE inhibitors have equivalent antihypertensive efficacy, do not impair carbohydrate and lipid homeostasis or peripheral perfusion and can effectively improve LVH. Certain ACE inhibitors may even slightly ameliorate abnormal insulin sensitivity and plasma glucose levels. While alpha-blockers share most of these desirable properties, these agents are more prone to precipitate orthostatic hypotension in the diabetic patient. The non-thiazide diuretic indapamide and the serotonin2-antagonist ketanserin also combine antihypertensive efficacy with metabolic neutrality. The ultimate goal of therapy is to improve life prognosis. In essential hypertension, conventional drug treatment based on diuretics in high dosage satisfactorily reduced cerebrovascular but not coronary complications or sudden death. In diabetic patients, the influence of antihypertensive therapy on prognosis has not been assessed prospectively. Based on retrospective analyses, Warram et al reported a 3.8 times higher mortality in diabetics treated with diuretics alone, than in diabetics with untreated hypertension (Arch Intern Med. 1991;151:1350). H. H. Parving calculated that effective BP control in patients with diabetic nephropathy might reduce 10 year-mortality from about 65 to 20 percent (J Hypertension. 1990; 8[Suppl 7]:187).(ABSTRACT TRUNCATED AT 400 WORDS)


Endothelin-induced vasoconstriction and calcium antagonists.

Endothelial cells can produce contracting factors; endothelin, a 21-amino acid peptide, is one of the most potent of these factors, which can control local vascular tone. The peptide is formed from its precursor, big endothelin, via the activity of the endothelin converting enzyme. The basal production of the peptide is stimulated by epinephrine, angiotensin II, arginine vasopressin, transforming growth factor beta, thrombin, interleukin-1 and the calcium ionophore A23187. In vascular smooth muscle cells, endothelin binds to its specific receptor (ETA-receptor and possibly ETB-receptor) which activate phospholipase C and lead to the formation of inositol trisphosphate, diacylglycerol and increased intracellular calcium levels. In certain blood vessels, the endothelin receptor is linked to voltage-operated calcium channels via a Gi-protein. This linkage may explain why calcium antagonists inhibit endothelin-induced contractions in certain, but not other blood vessels. In large conduit arteries, such as the human internal mammary artery, endothelin-induced contractions are primarily mediated by release of intracellular calcium and hence, calcium antagonists do not markedly affect the response. In contrast, in the human forearm circulation, calcium antagonists of different classes do prevent endothelin-induced contractions. Similarly, in mesenteric resistance arteries of the rat, calcium antagonists can reverse endothelin-induced contraction suggesting that calcium antagonists are particularly potent in inhibiting endothelin-induced contraction in resistance arteries, where peripheral vascular resistance and hence, blood pressure is regulated.


Effects of antihypertensive agents on carotid pulse contour in humans.

The aim of this study was to assess the influence of antihypertensive agents on arterial wave reflections (AWR) and carotid pulse pressure (PP) in humans. Twenty patients with hypertension (predominantly systolic) were studied. After one month of placebo therapy they were randomly assigned to atenolol (At) 50 mg/day or to nitrendipine (Ni) 40 mg/day. Carotid pressure waveform was recorded noninvasively by applanation tonometry using a Millar micromanometer-tipped probe. Arterial wave reflections were quantified as the ratio of the height of the late systolic peak (delta P) to the total height of carotid pulse pressure wave as an augmentation index (delta P/PP). Travel time of the reflected wave (delta tp) was timed from the foot of the pressure wave to the foot of the late systolic peak. Atenolol and Ni were equally effective in reducing sphygmomanometric brachial artery blood pressure (BP). Whereas At (p < 0.05) and Ni (p < 0.01) reduced the carotid PP, Ni (p < 0.01) but not At significantly reduced delta P/PP. Both agents increased the delta tp (p < 0.01) and decreased aortic PWV (p < 0.01). Nitrendipine was associated with a decrease in left ventricular ejection time (LVET) (p < 0.01), while At increased heart period (p < 0.01) and LVET. The LVET/delta tp ratio decreased after Ni (from 3.25 +/- 0.77 to 2.42 +/- 0.73; p < 0.01) but did not change after At. The study shows, that for the same effect on peripheral BP, Ni has a more pronounced effect on pressure wave in central arteries, resulting from an improvement in the timing between the ventricular ejection and AWRs.


The antihypertensive effect of verapamil in patients with chronic renal failure.

The calcium antagonist verapamil has been demonstrated to be effective in reducing hypertension in patients in whom sodium intake was not restricted. The present study evaluated the effect of verapamil in reducing hypertension in patients with chronic renal failure on low or high sodium diets. Also, the present study evaluated the effect of verapamil on proteinuria in chronic renal failure patients who were administered a normal and low protein diet. The results reveal that verapamil-SR 240 mg daily is effective in reducing hypertension in patients with chronic renal failure and the effect of verapamil is equal in patients on a high or low sodium intake. In addition, verapamil-SR 240 mg daily is effective in maintaining reduced proteinuria in chronic renal failure patients on low protein diet and may prevent proteinuria in such patients on a normal protein diet. Therefore, verapamil-SR 240 mg daily appears to be an excellent choice for the treatment of hypertensive chronic renal failure patients.


Atherosclerosis and calcium antagonists: the VHAS. The Verapamil-Hypertension Atherosclerosis Study (VHAS) Investigators.

Whether or not some classes of antihypertensive drugs have an anti-atherogenic action independent of the antihypertensive one has been investigated through a large series of experimental studies, primarily involving calcium antagonists. Most experimental investigations have shown a significant anti-atherogenic action of calcium antagonists, but only when the drug is administered simultaneously with the atherogenic stimulus (mainly cholesterol feeding). When the drug is administered weeks or months after the beginning of the atherosclerotic process (as in the Watanabe heritable hyperlipidemic rabbit), with a single exception, no antiatherogenic effect has been shown. The few clinical studies completed so far have been on symptomatic coronary patients. Little is known of the effects of calcium antagonists on asymptomatic lesions in the carotid arteries of hypertensive patients, in whom carotid plaques can be identified and followed-up by non-invasive ultrasound techniques. However, two such trials are underway. The Verapamil in Hypertension Atherosclerosis Study (VHAS) is an ongoing randomized trial, comparing the antihypertensive efficacy of verapamil 240 mg SR with chlorthalidone 25 mg in 1,464 essential hypertensives aged 40-65 years. In a random subgroup of patients (500), who will be followed for three years, B-mode ultrasonography is being carried out blindly to evaluate the effect of the two drugs on carotid wall thickness and on carotid plaques, when present. Preliminary baseline data are available in 440 of the hypertensive patients in whom ultrasound investigation was performed. The mean (+/- SD) age of these patients was 53.7 +/- 6.9 years; 32.5% had echocardiographically normal carotid walls; 30.9% showed intima-media thickening; and 36.6% had one or more plaques.(ABSTRACT TRUNCATED AT 250 WORDS)


Ambulatory blood pressure monitoring and antihypertensive treatment.

Ambulatory blood pressure monitoring is becoming increasingly popular among clinicians and investigators because of its potential to overcome the well-known limitations inherent to conventional blood pressure measurement. This paper will focus on the use of this approach in the evaluation of antihypertensive treatment. It will be argued that due to lack of prognostic validity and high cost, ABPM should not be employed routinely in treating hypertensives. It should always be employed, however, for the evaluation of the efficacy of new hypertensive drugs for which its superiority over sphygmomanometry is indisputable. This is exemplified by the results of a recent multicenter, double-blind, parallel group study on the effect of verapamil SR 240 mg, enalapril 20 mg and nitrendipine 20 mg and placebo, all administered once a day for eight weeks. Compared to placebo, all drugs reduced 24-hour mean blood pressure sufficiently. The reduction was evident throughout the daytime but nighttime blood pressure was more effectively lowered by verapamil and enalapril than by nitrendipine, documenting a difference that was not visible by using conventional measurements.


The pharmacologic management of maxillary sinus elevation surgery.

The edentulous posterior maxilla often has inadequate bone for endosteal implants. Therefore, implant placement in this area often requires the manipulation of maxillary sinus anatomy. The development of infection following sinus elevation procedures can occur from contamination of the site by oral and/or sinus pathogens or secondary infection from a maxillary sinusitis. The prevention and prompt treatment of complications associated with this surgery can contribute to increased success in this area. The prophylactic use of systemic and local antibiotics and glucocorticosteroids can reduce the risk of infection. If infection develops, culture and sensitivity testing is indicated, with the prescription of empiric antibiotic therapy and decongestants. A knowledge of clinical pharmacology and its therapeutic application is essential for the predictable management of sinus elevation surgery.


Clinical response of hard tissue replacement (HTR) polymer as an implant material in oral surgery patients.

This study evaluated the performance of a synthetic implant material, Hard Tissue Replacement Polymer, for: (1) ease of handling, (2) compatibility with bone and soft tissue, (3) stability of augmentation over time, and (4) development of untoward effects. HTR (a registered trademark of HTR Sciences, a division of United States Surgical Corporation, Norwalk, CT 06856) was implanted into 34 patients by means of five different surgical procedures. The material was found to be easy to manipulate during surgery. Tissue and bone compatibility, defined as absence of inflammation, was present in 32/34 surgical sites (94%). In extraction sites during the 18-month follow-up, no measurable decrease in bone height or width was seen. One patient with a large periodontal endodontic defect developed a post-operative infection necessitating extraction of the tooth. No induction of bone was seen in response to placement of HTR material.


Part I. Reconstruction after total mandibulectomy with free cranial and microvascular iliac crest grafts as preparation for implants.

A young Ecuadorian girl underwent a total mandibulectomy due to infected fibrous dysplasia. In the subsequent 16 years, she was unable to speak intelligibly or masticate, surviving on liquids alone. After referral to the United States, the patient underwent six major surgical procedures that reconstructed her mandible from cranial and microvascular iliac crest grafts. The reconstruction improved her appearance and prepared her for insertion of dental implants and the eventual construction of a prosthetic device. These resulted in both functional and esthetic benefits.


Part II. Mandibular reconstruction: combined intra-oral and in vitro placement of osseointegrated implants into a free and vascularized bone graft.

A 28-year-old Hispanic girl underwent a complete mandibular reconstruction many years following full mandibulectomy for fibrous dysplasia. Because of infectious complications, both free cranial and microvascular iliac crest grafts were used. The patient had osseointegrated implants placed directly into the grafted mandible. Osseointegrated implants were also placed into a segment of free iliac crest bone, in vitro, and then grafted laterally onto the reconstructed mandible. Prosthetic reconstruction was then carried out to restore the patient to normal function, health, comfort, and esthetics.


Solving the problem of violated intermaxillary space caused by poor pre-planning and improper placement of endosseous implants: a case report.

Every dental implant patient needs thorough evaluation and pre-surgical planning. It is imperative for the practitioner to have absolute knowledge of the implant system to be used. Nevertheless, sometimes we find ourselves in very difficult, almost unrestorable, situations. Often, we cannot rely on the implant manufacturers, and we have to be ready to customize some parts in order to solve difficult clinical situations. This case report shows how customized magnet keepers were fabricated by use of plastic IME's as casting patterns in order to solve the problem of violated intermaxillary space.


Correlative transmission electron microscopic and scanning electron microscopic observations of the tissues supporting endosteal blade implants.

Correlated scanning electron microscopic (SEM), routine transmission electron microscopic (TEM), and high-voltage transmission electron microscopic (HVEM) observations demonstrated that one-stage and two-stage endosteal blade-type implants were well-supported by mandibular tissues after five months of unloaded healing in dogs. Areas of the implants were apposed directly by mineralized tissues without any apparent interposed unmineralized connective tissue. Other areas of the implants were apposed by narrow areas of unmineralized tissue, often containing osteoblasts. These unmineralized areas were interposed between the implant and a supporting mineralized matrix. A healthy mix of tissues, which represented a dynamic osseous complex, supported these serviceable blade-type dental implants. This study, for the first time in the dental implant literature, utilizes HVEM stereology for evaluation of the bone-implant interface.


Finite element analysis (FEA) studies in 2.5-mm round bar design: the effects of bar length and material composition on bar failure.

The round bar/overdenture prosthesis is commonly used in the restoration of the totally edentulous implant patient. The length of bar span and types of alloys used in clinical cases have raised questions related to beam flexure and its role as a possible etiology of reported clinical failures in cast alloy systems. Three-dimensional finite element analyses were thus conducted on a 2.5-mm round bar for investigation of mechanical performance with respect to failure potential as a function of bar length and bar material property. Specifically, three bar lengths (6 mm, 12 mm, and 18 mm) and three alloy materials were analyzed, representing a clinical range of usage. The ends of each bar were modeled fixed to a 2.5-mm coping which was attached to a 3.8-mm root-form-type implant. The implant was modeled rigidly fixed in a representative block of bone. A 200-N occlusal force was applied to the model, as would be transmitted through an attachment clip, 5 mm in length, for the three respective bar lengths. The results of these analyses suggested possible yielding (or failure) in the 18-mm case. Bar length was found to play a stronger role in the adequacy of the overall design as compared with changing material properties in the range of alloy stiffnesses tested. Factors of safety with respect to static yield strength ranged from 2.82 to 66.46 for the designs evaluated. Fatigue factors of safety ranged from 1.63 to 38.88. A factor of safety of 5 or greater is suggested for the design of round bar systems in order for bar failure to be prevented.


Short-term plasma-cleaning treatments enhance in vitro osteoblast attachment to titanium.

The purpose of this research was to characterize the in vitro cellular behavior of osteoblast-like cells on titanium surfaces prepared with argon plasma-cleaning (PC) treatments for various lengths of time. The highest levels of cell attachment were observed for surfaces which had been plasma-treated for one min. Surface analyses indicated that although PC treatments dramatically improved surface wettability, the presence of inorganic contaminants was observed with longer treatment times and may have interfered with cell attachment. Further work is suggested to investigate the longer-term phenotypic expression of osteoblasts when grown on implant surfaces.


Early uncovering of HA-coated cylinder implants: case report of an in vivo shear strength test.

A new approach was used to test the readiness of an HA-coated implant for commencement of prosthetic procedures after two months of bone healing in humans. A torquing device was used for clinical measurement of the shear resistance of the supporting bone. It was found that the bone was capable of resisting a shear force just slightly greater than that which was necessary to produce displacement of implants placed in dog femurs with a comparable bone-healing period and with healing to full maturity. This report suggests that it may be feasible to uncover HA-coated implants after two months of bone healing.


Dental implant treatment in a severely compromised (irradiated) patient.

When faced with a patient with relative medical or psychological contra-indications, the practitioner may be tempted to withhold dental implant treatment because of the risks. Yet, for some highly motivated but compromised patients, the potential benefits of implant treatment can be an overriding consideration. In the case presented here, a 56-year-old patient who had undergone two series of radiation therapy and surgery for recurring cancer of the tongue was treated first with a subperiosteal, and, when the subperiosteal was removed after six years, the patient was treated with endosseous implants. This treatment significantly improved the patient's life without further negative effect on her medical condition.


Overview of factors important in implant design.

Forty-two percent of the population over the age of 65 is totally edentulous. The use of dental implants as a means of treating these patients has accelerated in the last decade, and there are now 300,000 dental implants used in the United States. It is therefore imperative that a greater understanding of the parameters which govern the long-term success of implants be developed. In order for the effectiveness of implants to be better quantified, a fundamental, quantitative understanding of the physical parameters governing the complex synthetic material/tissue aggregate is needed. The design of an "optimal" implant requires the integration of material, physical, chemical, mechanical, biological, and economic factors. The approach taken for a specific property objective to be met should be based on a materials science approach, in which the synergistic relationships among processing, composition, structure, and properties are characterized. Implant success is a function of biomaterials and biomechanical factors, including: materials and material processing; mechanisms of implant/tissue attachment; mechanical properties; implant design; loading type; tissue properties; stress and strain distributions; initial stability and mechanisms of enhancing osseointegration; biocompatibility; and surface chemistry, mechanics, and bone-binding ability of the implant. This paper presents an overview of physical parameters important to implantology. Following a general presentation of implantology concepts, the physical parameters listed above are discussed in greater detail.


Micromechanics of implant/tissue interfaces.

A series of finite element models was developed for evaluation of the micromechanics of implant/tissue interfaces. Conventional finite element global models of a dental implant, assuming a continuum implant/bone interface, were developed so that general stress patterns in the implant and surrounding tissue could be obtained. Stresses in bone were concentrated on the alveolar crest and apex region for all global models having a direct bone/implant contact. The addition of a 100-microns-thick layer of fibrous tissue into the bone/implant interface concentrated the stresses in the middle third of the bone adjacent to the implant surface. Stresses in the middle third were ten times higher than in the cases without fibrous tissue. Interfaces modeled under the assumption of a volume-weighted average material stiffness of bone tissue and metal confirmed these general stress patterns, but provided no stress details of the interfacial zone. Finally, the equivalent material constants of the interfacial zone with and without fibrous tissue were calculated by homogenization theory. From these equivalent constants, local strains around single threads were calculated. These equivalent material properties are sensitive to the microstructure. Therefore, it is now possible for stress patterns within the interfacial zone to be quantified and the local micromechanical behavior around individual surface structures for whole implants accounted for.


A brief introduction to advanced surface modification technologies.

Techniques for the modification of surfaces are evolving rapidly. In implantology, few of the newer surface modification techniques have been used. The purpose of this paper is to provide an introduction to advanced surface modification processes that could be useful in dental implant manufacturing. There are three general techniques used to modify surfaces: add material, remove material, and change the material already present. Several processes for the addition of material to surfaces are described in this paper. Two new processes that can create relatively thick coatings are sol-gel and plasma-spraying. Several new processes making thin film coatings (sub-micron) have come from the electronics and optics industries. These are vapor deposition techniques, where the coating material condenses onto a surface from a vapor. The three basic vapor deposition techniques are: evaporation, sputtering, and chemical vapor deposition. New processes for the removal of material from surfaces, often for cleaning purposes, are glow discharge treatment and sputter-etching. Surface properties can also be changed without addition or removal of material by use of laser and electron beam thermal treatments. Ion implantation can be used to add material to surfaces, modify coatings, and change microstructures. The techniques outlined in this paper have great potential for improving implants.


Radiofrequency gas plasma (glow discharge) disinfection of dental operative instruments, including handpieces.

The radiofrequency-stimulated argon gas plasma (glow discharge) technique, already well-known for surface cleaning and activation of adhesion, was investigated for determination of its separate potential for rapid disinfection of dental operative instruments. Disinfection effectiveness was judged from diminished post-treatment recovery of viable organisms from the instruments agitated in saline. Streptococcus salivarius, Bacillus stearothermophilus, and Escherichia coli were used as primary contaminant organisms, dried from gelatin-thickened laboratory cultures onto the instruments and not subjected to any preliminary cleaning steps. Significant disinfection was obtained, with no sensible temperature increases, in under 10 minutes in laboratory apparatus consuming fewer than 5 Watts of power per cycle. Also, clinically used and deliberately-saliva-contaminated high-speed handpieces were gas-discharge-treated, with their resultant rapid disinfection noted by complete suppression of the viability of any transferred natural contaminant organisms within two minutes. With regard to preservation of instrument quality, it was also shown that this low-temperature gas-discharge method provides the noted substantial disinfection without deterioration of sharp edges. Work now in progress suggests that the method can provide cool, rapid, and complete sterilization when hydrogen peroxide vapors are present in the gas plasma used for treatment of instruments first given the normally recommended thorough pre-cleaning.


Biological requirements for material integration.

The recognition that synthetic devices can provide functional replacements for failed teeth, or for previously edentulous areas, has resulted in increased emphasis being placed on understanding of the interactions between synthetic materials and host tissues in order for the success of these devices to be optimized. A key to achievement of an optimal biological interface between the implant and the surrounding tissue is through an understanding of host response to materials. This article reviews the biological requirements for implant-tissue integration, with specific focus on the role of adhesion molecules and cytokines (growth factors) in this process. Adhesion molecule/cytokine interactions are discussed, and in particular the possible role for osteopontin, an adhesion molecule as well as a cytokine, is considered in wound healing. Finally, the causes of peri-implantitis are discussed, and methods of decontamination are presented. The decontamination methods focus on enhancement of cell adhesion and integration to the altered implant surface.


Tatum custom ramus frame implant: multiple options including treatment for combination syndrome.

The advantages offered by the Tatum custom ramus frame include its extended posterior arms, its ability to form a solid interface, and its availability in numerous sizes. It has solved some of the problems associated with the earlier models of the ramus frame. It offers stable support for a removable prosthesis in the completely edentulous mandible. In cases of combination syndrome, where a hopeless anterior dentition must be removed, a ramus frame can be placed immediately into the extraction sites. In a severely atrophied alveolar ridge, bone augmentation can be performed simultaneously with the ramus frame placement surgery. This implant device can, moreover, restore the patient's stomatognathic system to comfort, function, and pleasing esthetics quickly and economically. Furthermore, statistics show a 97% survival rate over 18 years (Tatum, 1992). Although the surgical procedure for the custom ramus frame is more complex than that for root-form and some subperiosteal procedures, and patients must be carefully selected, the custom ramus frame provides improved strength and load resistance.


Force transfer in implant dentistry: basic concepts and principles.

The mechanism and efficiency of force transfer by dental implants to contiguous biological tissues are clearly important determinants in the development of the implant-to-tissue interface and, indeed, implant longevity. Whether a clinician seeks to gain a better understanding of implant design rationale and/or to implement biomechanics concepts in patient care, a fundamental, yet clinically relevant, understanding of biomechanics is required. A primer in force transfer is thus presented, with particular attention focused on implications for the long-term success of dental implants and restorative procedures. Forces and their components, moments, force transfer mechanisms, impact, and stress-strain relationships all influence clinical decisions and treatment plans.


A study of the effect of magnetized water on enzyme activities by potentiometric enzyme electrode method.

A very promising glutamate decarboxylase electrode, which has linear response range of 5.6 x 10(-5)-1.2 x 10(-2) mol/L. Nernstian slope of 50 mV/decade, detection limit of 3.2 x 10(-5) mol/L and response time less than 3 min, has been designed to observe and evaluate quantitatively the effect of magnetized water on enzyme activities by potentiometric enzyme electrode method. It was found that the activity of glutamate decarboxylase can increase by 30% in magnetized water. The mechanism of increased enzyme activity was discussed in the present paper. Such a new finding will probably lead to some new explanations for the physiological and biological mechanism of the effect of magnetized water on living organisms, thus providing a new approach to the study of the effect of magnetized water.


Effects of cigarette smoking on the function of metabolizing arachidonic acid and angiotensin I in the isolated perfused rat lungs.

The effects of acute and chronic cigarette smoking on the metabolism of exogenous arachidonic acid (AA) and angiotensin I (AI) in perfused isolated rat lungs were studied. The results showed that acute cigarette smoking did not alter the contents of 6-keto-PGF1 alpha (the stable metabolite of PGI2) and TXB2 (the stable metabolite of TXA2) in the effluent and the increment of pulmonary artery pressure (delta Ppa) caused by AA. The conversion of A I into A II was significantly increased (P < 0.01), while the delta Ppa induced by A I injection was obviously decreased as compared with controls (P < 0.05). After cigarette smoke exposure for 30 days, the delta Ppa caused by AA or A I did not differ from that of controls, but the contents of 6-keto-PGF1 alpha and A II increased more markedly than those in non-smoking rats (P < 0.05). It is suggested that acute and chronic cigarette smoking in rats can promote the lung function of converting A I into A II, chronic smoking can increase the lung function of metabolizing AA into PGI2.


Effects of microinjection of L-glutamate into locus coeruleus complex area on respiration.

The experiments were performed on 55 rabbits vagotomied, anesthetized with urethane and immobilized with flaxedil. Injection of L-glutamate (L-glu) into the locus coeruleus complex (Lc-Sc) area led to a marked increase in respiratory frequency (RF) and phrenic nerve discharge rate (phr.d) (16 +/- 3.5% and 6.5 +/- 2.5%; P < 0.01 and P < 0.05, respectively), a decrease in inspiratory and expiratory duration, and no obvious change in blood pressure (Bp) was observed. While prazosin (0.5 micrograms/microliters), yohimbin (4 micrograms/microliters) and propranolol (2 micrograms/microliters) were preinjected into the nuclei tractus solitraii (NTS) respectively, the above-mentioned effects of L-glu on respiration was blocked. These results indicate that the excitation of neurons in the Lc-Sc can induce an increase in RF and phr. d and the excitative effect of L-glu on RF was mediated by alpha 1, alpha 2 and beta-receptors in the NTS, while the effect on phr.d was mediated differently.


Effects of electroacupuncture of "zusanli" acupoint on high blood pressure and blood hyperviscosity in stress rats.

Elevation of blood pressure (BP) and blood viscosity (BV) was induced in unanesthetized Wistar rats by fixing and hanging. Electroacupuncture of "Zusanli" acupoint or microinjection of GABA (60 micrograms/10 microliters) into the IV ventricle of the brain could lower the high BP and BV induced by fixed-hanging, which could be blocked by a microinjection of GABAA receptor antagonist bicuculline (60 micrograms/10 microliters). The results showed that the depressant effect of electroacupuncture of "Zusanli" acupoint on high BP and blood hyperviscosity induced by fixed-hanging might be mediated by the activation of GABAA receptors in the brain.


The screening diagnosis of tetrahydrobiopterin deficient phenylketonuria.

Since 1990, 20 diagnostically confirmed phenylketonuria (PKU) patients have been screened with a tetrahydrobiopterin (BH4) loading test, in which plasma phenylalanine and urinary pterin metabolites were investigated, ind activity of dihydropteridine reductase (DHPR) was determined as well. The results showed that there was no statistical difference between the concentrations of plasma phenylalanine before and after BH4 (20mg/kg) administration in all patients, and values of urinary neopterin and biopterin were within the range of classic PKU. All patients but one had normal activity of DHPR in red cells. This suggests that incidence of BH4 deficiency in PKU patients amounts to five percent (1/20) which is almost the same as reported abroad.


Hypothalamic-pituitary function assessment in children by a combined stimulation test.

We utilized a combined stimulation test using insulin, thyrotropin-releasing hormone, gonadotropin-releasing hormone and levodopa to assess multiple pituitary hormones including growth hormone, thyrotropin, prolactin and gonadotropins in 32 children of short stature and 18 girls with early appearance of puberty. It was found that this combined stimulation test can assess multiple hormone responses with satisfactory results in a single 90-min test. Compared with any of those laborious classic stimulation tests alone, it is easier to be carried out and willingly accepted by children.


Changes in serum fibronectin levels at delivery in pregnant women and their fetuses with idiopathic fetal growth retardation.

We determined maternal and neonatal umbilical artery serum concentrations of fibronectin (Fn) in 15 pregnant women with idiopathic IUGR (Intrauterine growth retardation) and 17 normal pregnant women at the time of delivery, by use of a rate nephelometric procedure. The results showed that the maternal serum levels of Fn in pregnant women with idiopathic IUGR were significantly higher than those in normal pregnant women at the time of delivery (P < 0.01), but umbilical artery serum concentrations in the two groups were not significantly different (P > 0.05), suggesting that the significant increase in maternal serum levels of Fn appeared to be related to uteroplacental vascular endothelial cell lesion, formation of microthrombi and deficiency of placental perfusion.


Monocrotaline-induced structural remodeling of the intra-acinar pulmonary arteries and pulmonary hypertension.

The monocrotaline-induced structural changes of small pulmonary arteries in rat and their relationship with pulmonary hypertension and right ventricular hypertrophy were observed by determining the right ventricular systolic pressure, and by light and electron microscope and morphometry. One to 38 days after last injection of monocrotaline (MCT), a medial thickening and lumen marrowing of the circular muscular arteries (CMA), accompanying terminal (TB) and respiratory bronchioles (RB), were found. And there after the lumen of CMA, accompanying TB, became dilated, and its medial thickness (MT) decreased, whereas the histopathologic changes of the partially muscular arteries (FMA), accompanying RB, became severe, their MT increased continuously, and finally reached the peak value on Day 50. At the first day after last MCT treatment, inflammation and muscularization were found in PMA and nonmuscular arteries (NMA), and became more severe with the cause of disease. Therefore, the intra-acinar pulmonary arteries, both CMA and PMA, increased in number while the NMA decreased in number significantly because of the structural remodeling. Four days after MCT treatment, the right ventricular systolic pressure began to rise, and reached its peak value on Day 50. Eight days after MCT injection, right ventricular hypertrophy developed, and became most significant from Day 23 to Day 30. The results suggest that structural remodeling, i.e. muscularization, of intra-acinar pulmonary arteries plays an important role in the development of pulmonary hypertension and right ventricular hypertrophy.


A cytogenetic study of five rare karyotypes.

The results of chromosome analysis of 5 cases from our genetic counseling showed that among these patients, 4 had two or more repeated spontaneous abortions. Structural abnormalities with the karyotypes 46, XX, t(1;11)(q42;q13), 46, XY, t(17;19)(q21;p13.3), 46, XY, t(4;5)(p13;q35) were reported for the first time in the literature abroad. The karyotypes 46, XX, t(16;18)(q24;q21), 46,XX, t(3;8)(p21;q24.3) were reported for the first time in the literature at home. A discussion is made on the origin of chromosome aberration and the cause of repeated spontaneous abortions.


Comparison between laser and electrical ablation of ventricle in dogs: hemodynamic, pathologic and electrocardiographic observations.

To characterize and compare the pathologic, hemodynamic and electrocardiographic changes of both transcatheter laser and electrical energy on ventricle, 36 subendocardial myocardium lesions were induced at energy 60, 120 and 240 Joules by either transcatheter laser irradiation or electrical shock in 7 anesthetized dogs. The following results were observed: 1) Both laser and electrical ablation on myocardium created nonhomogeneous myocardium injury, but laser ablation caused mainly focal tissue vaporization and necrosis, while electrical shock induced widespread tissue degenerations; 2) Both laser and electrical induced-lesion dimensions increased parallel to the total dosage of energy; 3) Laser ablation caused mainly (90%) single ventricular premature beats and 86% of them occurred within the first minute after energy discharged, while ventricular tachycardias were found in any electrical energy groups; ventricular fibrillations occurring during laser and electrical ablation were 5% and 13% respectively (P < 0.01); 4) A decrease in aortic blood pressure and an increase in central venous pressure induced by laser ablation were significantly less than that produced by the same amount of electrical energy (P < 0.01). Our preliminary results have shown that transcatheter laser ablation has great potential for becoming a practical method in the management of refractory tachycardias.


An experimental study of trachea anastomosis in rabbits using carbon dioxide laser.

A technique of sutureless trachea anastomosis in rabbits using carbon dioxide laser was reported herein. In 6 rabbits with laser-assisted trachea anastomoses, only one was found to have slight anastomotic stenosis after operation, whereas 6 rabbits with conventional sutures all were found to have anastomotic stenosis. Results show that laser-assisted trachea anastomosis has certain advantages over the conventional suturing technique, thereby finding wide application in clinical tracheal reconstruction and lung transplantation.


A clinical application of artery-including silicone tubing to peripheral nerve defect.

7 cases of 11 peripheral nerve defects (5 median nerves, 5 ulnar nerves, and 1 radial nerve) were repaired through artery-including silicone tubing. The nerves have gaps within 3 cm in 9, and 3 to 5 cm in 2. Repairing the defect's location, 4 of them were below the axilla; 1 at the upper 1/3 part of the forearm and 6 at the lower part of the forearm. The duration of injuries was from 4 to 7 months, except one case lasting over a year. Six patients with 9 nerves involved had adequate follow-up of 6 to 9 months. One patient with 2 nerves was lost to follow-up. The results were excellent in 5 nerves (M4S3), good in 2 (M3S3), and poor in 2 (M1S1).


Surgical treatment of double-chamber right ventricle and its associated anomalies.

A report on the results of surgical treatment of 5 cases of DCRV and its associated anomaly was presented in this paper. No definite diagnosis of DCRV was made prior to operation. It was found that 2 cases had DCRV as an isolated anomaly, another 2 had the disease associated with VSD, and the remaining 1 had DCRV with right ventricle to left atrium cannulation. Muscular membrane septum type was found in 3 cases, and muscular bundle type in 2.4 cases diagnosed as having DCRV or DCRV with other heart anomalies during operation were treated properly and discharged fully recovered. 1 case died of acute heart insufficiency. Pathologic anatomy and physiology, associated anomalies of DCRV, and some experience with the operative approach were discussed in this article.


Effects of acute ingestion of ethanol on hemodynamics and hypoxic pulmonary vasoconstriction in dogs--role of leukotrienes.

The effects of acute intragastric administration of ethanol on hemodynamics and hypoxic pulmonary vasoconstriction were studied in spontaneously breathing dogs. The dogs were given 0.5 g/kg of 10% ethanol (v/v) in 5 min. Hemodynamic measurements were obtained before and 30 min after ingestion of ethanol. Mean pulmonary arterial pressure and pulmonary vascular resistance increased markedly after ingestion of ethanol, and hypoxic pulmonary vasoconstriction was augmented significantly by ethanol as well. Diethylcarbamazine citrate (DEC), a lipoxygenase inhibitor, inhibited these effects of ethanol in a dosage of 200 mg/kg. The above findings suggest that ethanol can induce pulmonary vasoconstriction, which may be predominantly mediated by leukotrienes (LTs).


Oncogenes, molecular biology and the head and neck surgeon.

Advances in the treatment of head and neck cancer in the last 15 years have been largely limited to those that impact on patient morbidity while patient mortality statistics remain static. The advent of new technologies in molecular biology and immunology may provide the head and neck oncologist with the tools to impact on patient survival. The head and neck surgeon of the future will be required to have a basic understanding of their potential applications and limitations.


[Antibacterial activity of rokitamycin against fresh clinical isolates].

We obtained bacterial strains which were clinically isolated and identified from outpatients with various infections in medical institutions throughout Japan. Possible antibacterial activities of rokitamycin (RKM) were examined against these isolates. Minimum inhibitory concentrations (MICs) were determined through a comparative study with reference drugs. The results of the study are summarized as follows. 1. Resistance patterns of 400 isolates which were highly resistant to macrolides (MLs) with MIC values > 100 micrograms/ml were classified into 55 patterns. Staphylococcus spp. showed cross resistance to 14-membered ring MLs with 100% cross resistance observed between erythromycin (EM) and clarithromycin (CAM), and 85.2% between EM and oleandomycin (OL). Fewer isolates showed strong resistance to 16-membered ring MLs than to 14-membered ring MLs. Cross resistances observed among the Staphylococcus isolates were 100% between acetylmidecamycin (MDM-AC) and kitasamycin (leucomycin (LM)), 93.9% between MDM-AC and josamycin (JM), and 53.3% between MDM-AC and RKM. Streptococcus spp. and Peptococcus spp. showed very similar resistance patterns to both 14- and 16-membered ring MLs, but resistance patterns to RKM were quite different. Most of anaerobic streptococci and Bacteroides fragilis group had similar resistance patterns to 14- and 16-membered ring MLs, but in some cases a pattern similar to that of Staphylococcus spp. was observed. 2. When ML-resistant bacteria isolated during 1975 to 1980 were compared to those isolated in 1986 and 1989, it was observed that resistance of Staphylococcus aureus remained almost unchanged, that of Streptococcus pyogenes was lower in the later years than during 1975 to 1980, but that of Streptococcus pneumoniae increased. 3. Most of ML-resistances of the resistant isolates were inducible, but extents of induction varied depending on drugs tested. Strong inductions were observed when 14-membered ring MLs were used, but inductions were minimal with 16-membered ring MLs. RKM appeared to induce resistance to the least extent. From these results, it appears that the RKM is quite useful clinically even in the 1990s.


[Clinical evaluation of cefprozil in children].

Cefprozil (CFPZ, BMY-28100), a new oral cephalosporin, was evaluated for its efficacy and safety in 42 children with bacterial infections (Table 1), and the following results were obtained. 1. CFPZ was administered in 3 or 4 divided doses at daily dosages ranging from 15.3 to 60.0 mg/kg to 42 patients (19 cases of acute tonsillitis and/or laryngitis, pharyngitis, 13 cases of pneumonia, 2 cases each of suppurative cervical lymphadenitis and UTI, and 1 case each of scarlet fever, acute otitis media, suppurative parotitis, impetigo contagiosa, furuncle and acute enteritis) and the following clinical results were obtained: excellent; 24 cases, good; 14 cases, fair; 4 cases. The overall efficacy rate was 90.5% (Table 3). 2. MICs of CFPZ against 50 strains of isolated organisms are shown in Table 4. In 19 cases out of 28 cases examined, causative organisms were successfully eradicated and strain of Staphylococcus aureus was decreased in 1 case. 3. Diarrhea was observed in 2 cases (cases 8, 11). In case 8, the symptom disappeared spontaneously. Case 11 improved immediately after the administration of the drug was stopped. Among 39 children who went through laboratory tests, eosinophilia which seemed to be related to the administration of this drug was observed in 2 cases (cases 29, 38). Slight elevations of S-GOT and S-GPT were found in 1 case (case 22) (Table 7). 4. These data suggest that CFPZ is a safe and useful new antibiotic in the treatment of children with susceptible bacterial infections.


[Clinical evaluation of a new oral cephalosporin, cefprozil, in pediatrics].

Cefprozil (CFPZ, BMY-28100), a new oral cephalosporin, was evaluated for its antibacterial activity and clinical efficacy. Thirty-four patients were treated with 7.7-36.2 mg/kg per day of CFPZ divided into 3 times. A total of 33 patients including 3 with acute pneumonia, 2 with acute bronchitis, 17 with acute upper respiratory tract infections, 4 with urinary tract infections, 1 with suppurative lymphadenitis and 6 with other soft tissue infections were evaluated for clinical efficacy except for 1 patient whose general conditions were too serious to continue to be treated with orally medication. Clinical effects were excellent in 8 patients and good in 23 but 2 cases were excluded because they were suspected for viral infections, hence the overall efficacy rate was 100%. Bacteriological responses were confirmed on 6 (66.7%) strains which were eradicated by the treatment out of 9 strains identified. CFPZ showed stronger antibacterial activities than those of cefaclor. Side effects or abnormal laboratory test results were observed in 2 patients; nausea and pallor of face in 1 patient and an increase of eosinophil in 1. The above findings suggest that CFPZ is a safe and useful antibiotics for the treatment of bacterial infections in pediatric patients.


[Clinical studies on cefprozil granules].

Cefprozil granule preparation was administered orally to 16 patients (ages ranging 8 months to 9 years and 6 months) with pediatric bacterial infections at daily dose levels between 29.4 and 35.7 mg/kg divided into 3 or 4 doses. The following results were obtained. 1. Sixteen patients including 5 with pharyngitis, 3 with tonsillitis, 3 with lacunar tonsillitis, 2 with pneumonia, 2 with contagious impetigo and 1 with scarlet fever were treated. Clinical effects were excellent in 9 cases and moderate in 7, with an overall efficacy rate of 100%. 2. Organisms suspected as pathogens included 17 strains (10 strains of haemophilus influenzae, 2 of Haemophilus parainfluenzae, 3 of Streptococcus pyogenes and 2 of Staphylococcus aureus). Bacteriologically, eradication of pathogens were observed for 11 strains, but no changes were obtained for 5 (all Haemophilus), and unknown results were obtained for 1, thus the eradication rate was 68.8%. 3. No side effects were observed. Abnormal laboratory test results included 2 cases of increase in platelets, and 2 of increase in eosinophils, but those were not significant. 4. No refusal of the drug occurred due to its taste or odor.


[Clinical studies on cefprozil in pediatrics].

Cefprozil (CFPZ, BMY-28100) fine granules were given orally to 21 children with acute bacterial infections including 15 cases of acute tonsillitis and 3 each of acute bronchitis and urinary tract infections. Good to excellent clinical responses were obtained in 19 of the 21 patients and bacterial eradications were obtained for all 11 strains found in these cases. Loose stool and eosinophilia were observed in 1 case each. From the above clinical results, it appears that CFPZ is a useful antibiotic for the treatment of pediatric patients with various bacterial infections.


[Clinical evaluation of cefprozil granules in pediatric field].

Cefprozil (CFPZ, BMY-28100) granules were administered to 20 children with bacterial infections: acute tonsillitis 8, acute bronchitis 10, purulent lymphadenitis 1, urinary tract infection 1. Daily doses ranged 29-50 mg/kg. The drug was given orally, 3 times a day and the durations of administration were 5 to 9 days. Clinical efficacies were excellent in 16 cases and good in 4 cases, hence the overall efficacy rate was 100%. No side effects were observed in any of these cases. As for abnormal laboratory test values, thrombocytosis was observed in 1 case. From the above results, we consider CFPZ granules to be a useful drug for the treatment of pediatric patients with various bacterial infections.


[Clinical study on cefprozil fine granules].

Cefprozil (CFPZ, BMY-28100), a new non-ester cephem, was administered to 15 pediatric patients with infectious diseases. The patients included 6 boys and 9 girls from 10 months to 11 years old and they were given oral doses of 18.5-41.7 mg/kg/day for 3 to 8 days. Clinical efficacies were excellent in 3 cases and good in 12 cases, hence the total efficacy rate was 100%. Eosinophilia occurred in 1 case as side effect of the drug, but no other side effects were not found during or after the treatment.


[Basic and clinical studies on cefprozil in pediatrics].

1. Serum levels of cefprozil (CFPZ, BMY-28100) after single oral administration of 7.5 mg/kg were 2.9-5.5 micrograms/ml at 1 hour and trace at 6 hours. 2. Urinary excretion rates of CFPZ were 45.7-102.3% within 6 hours (HPLC). 3. CFPZ was administered at doses ranging 19-47.3 mg/kg/day to 17 cases of pediatric infections including 16 cases with respiratory infections and 1 case with external otitis. Good clinical and bacteriological responses were obtained in all cases. 4. As side effect, diarrhea was observed in 1 case. As abnormal laboratory test results, eosinophilia was observed in 5 cases.


[Therapeutic effects of cefprozil in the treatment of various infectious diseases in children].

Therapeutic effects of cefprozil (CFPZ, BMY-28100), a new cephalosporin, were examined in various infectious diseases in children. Clinical efficacy rates were 50% (2/4) in acute bronchitis, 80% (4/5) in pharyngitis, 0% in laryngitis, 100% (7/7) in tonsillitis, 100% (8/8) in impetigo contagiosa, furuncle and posthitis. Hence, the overall efficacy rate was 84% (21/25). Adverse effects were observed in 1 case with slightly elevated serum GOT and GPT. Changes in serum concentrations and urinary excretion of CFPZ were examined in 4 and 2 children without infection, respectively. T 1/2 values obtained were between 1 hour to 2 hours (bioassay). Six hour recovery rates in urine were 51.8% and 77.8% (bioassay). CFPZ was considered to be a safe and useful drug in treating various infectious diseases in children.


[Clinical studies on cefprozil granules in pediatric skin soft tissues infections].

Cefprozil (CFPZ), a newly developed cephalosporin in fine granular form, was administered to pediatric patients with skin and soft tissue infections. MICs were determined for 6 drugs including CFPZ, cephalexin (CEX), cefaclor (CCL), ampicillin (ABPC), methicillin (DMPPC), cloxacillin (MCIPC) against 53 clinical isolates of Staphylococcus aureus from these patients. An inoculum size of 10(6) CFU/ml was used in the MIC-determinations. CFPZ was given to 73 patients with ages ranging from 6 months to 10 years and 8 months and 71 cases were evaluable for clinical effects as follows; impetigo (65), Staphylococcal scalded skin syndrome (1), furuncle (1), subcutaneous abscess (3), and periproctal abscess (1). To study clinical efficacy, bacteriological effects and safety of this drug, a mean dose of 8.4 mg/kg with 3-4 daily dosages (57 cases of t.i.d. and 14 cases of q.i.d.) was administered for an average of 6 days. The results obtained are summarized as follows. 1. With regard to the 53 isolates of S. aureus, MICs of CFPZ against 52 strains (98.1%) ranged from 0.78 to 3.13 micrograms/ml. 45 strains (84.9%) were inhibited at 0.78 micrograms/ml. MIC90 of CFPZ was 1.56 micrograms/ml, but MIC against 1 strain of Methicillin-resistant S. aureus (MRSA) was 100 micrograms/ml. The MIC90 of CEX and CCL were 6.25 micrograms/ml and MIC of CEX and CCL against 1 MRSA strain were 200 and 100 micrograms/ml, respectively. The MIC90 of ABPC, DMPPC and MCIPC were 6.25, 3.13 and 0.39 micrograms/ml, respectively. CFPZ showed the second highest activity after MCIPC against S. aureus. 2. CFPZ showed very good clinical responses and clinical effects in 71 patients all of whom judged by doctors in charge as having "good" or better responses. 3. For impetigo patients, the evaluable cases by score 3, 5 and 7 days after administration of the drug were 52, 39 and 20 patients, respectively. The efficacy rates on these days were 90.4, 100 and 100%, respectively. The efficacy rate at a daily dose of 30.1-45.0 mg/kg on day 3 was 17.2% higher than that at 22.5-30.0 mg/kg, and the "excellent" response rate of 30.1-45.0 mg/kg group was 45.3% greater. Because of these results, it is expected that good clinical effects can be obtained at a daily dose of 22.5-30.0 mg/kg of CFPZ, but better responses can be expected at 30.1-45.0 mg/kg in 3-4 divided doses given for 5 days. 4. Bacteriological effects of CFPZ were determined against 60 strains of S. aureus.(ABSTRACT TRUNCATED AT 400 WORDS)


[Pharmacokinetic and clinical studies on cefprozil granules in the pediatric field].

Cefprozil (CFPZ), a newly developed oral cephalosporin in a fine granular form for pediatric use, was administered to children with bacterial infections. MICs were determined for 6 drugs including CFPZ, cephalexin (CEX), cefaclor (CCL), ampicillin (ABPC), methicillin (DMPPC) and cloxacillin (MCIPC) against the following 84 strains isolated from cases to which CFPZ was administered; 55 strains of Gram-positive cocci (GPC) including 2 strains of Staphylococcus aureus, 49 strains of Streptococcus pyogenes, 4 strains of Streptococcus pneumoniae, and 29 strains of Gram-negative bacilli (GNB) including 10 strains of Haemophilus influenzae, 18 strains of Escherichia coli, and 1 strain of Proteus mirabilis. MIC determination of these strains was done with an inoculum size of 10(6) CFU/ml. In pharmacokinetic studies, serum concentrations, urinary concentrations and urinary recovery rates were investigated using bioassay and high-performance liquid chromatography (HPLC). CFPZ was orally administered 30 minutes before meals to 9 children with ages ranging from 7 years and 1 month to 12 years and 3 months. Three groups of 3 children were tested with doses of 4.0, 7.5 and 15.0 mg/kg, respectively. In addition to the above, clinical and bacteriological studies were performed in a total of 160 cases consisting of children with ages ranging 5 months to 12 years and 5 months. A mean dose of 8.6 mg/kg in 3-4 divided doses (130 cases of t.i.d. and 30 cases of q.i.d.) was administered for an average of 7 days. The 160 cases included 34 cases of pharyngitis, 5 cases of tonsillitis, 8 cases of acute bronchitis, 8 cases of pneumonia, 52 cases of scarlet fever, 4 cases of acute purulent otitis media, 47 cases of urinary tract infection, 1 case of purulent lymphadenitis and 1 case of posthitis. Adverse reactions and abnormal clinical laboratory test results were also examined in 166 cases, including 6 cases excluded from the evaluation of clinical efficacy. The results obtained are summarized as follows: 1. With regard to GPC, MICs of CFPZ against 2 strains of S. aureus were 0.78 or 1.56 micrograms/ml and CFPZ showed the second highest activity to MCIPC. MICs of CFPZ against 49 strains of S. pyogenes were all less than 0.025 micrograms/ml.(ABSTRACT TRUNCATED AT 400 WORDS)


[Pharmacokinetic and clinical studies of cefprozil fine granules in children].

Cefprozil (CFPZ, BMY-28100) is a new oral cephem antibiotic without an ester linkage. Pharmacokinetic and clinical studies using CFPZ 10% fine granules were performed in pediatric patients. 1. Pharmacokinetic investigation Peak serum concentrations of CFPZ after dose of 7.5 mg/kg and 10 mg/kg were, respectively, 3.65 +/- 0.24 micrograms/ml and 6.38 +/- 3.23 micrograms/ml at 1-2 hours. The average half-life with 7.5 mg/kg administration was 0.90 +/- 0.16 hours and that with 10 mg/kg was 1.29 +/- 0.50 hours. The urinary excretion of CFPZ was about 45% (35.3-50.0%) in 6 hours. 2. Clinical investigation Enrolled in the study were 22 patients including 4 with pharyngitis, 3 with tonsillitis, 3 with bronchitis, 5 with pneumonia, 4 with urinary tract infection, and 1 each with pertussis, purulent lymphadenitis and otitis media. Responses were excellent in 14 patients, good in 5 patients and fair in 1 patient. In the assessment of the bacteriological efficacy, 8 out of 17 strains of organism identified previous to the treatment were eradicated, 5 strains were found replaced by other bacteria and 4 strains persisted, hence the eradication rate was 76.5%. 3. No adverse reactions attributable to the drug were observed. From the above results, it has been concluded that CFPZ is a highly effective and safe agent for moderate respiratory and urinary tract infections in children.


The relationship between mitral valve prolapse and acute rheumatic fever in pediatric patients.

Mitral valve prolapse (MVP) is a clinical syndrome of which mitral regurgitation and congestive heart failure are the late sequelae. It can be usually diagnosed by echocardiography. In this study, we reevaluated the patients with acute rheumatic fever (ARF) who were followed-up regularly for aspects of MVP. Physical examination, echocardiography and Doppler study were performed for all the patients. One hundred twenty-seven cases of polyarthritis (54.7%), and 105 cases of valvular involvement (45.3%) were diagnosed. Echocardiography demonstrated MVP in 46.8% with isolated mitral insufficiency, in 38.2% with combined valvular defect and in 12.6% with only polyarthritis. One hundred healthy children comprised the control group. Statistical analyses revealed a significant difference in favor of valvular involvement between the groups.


Doppler assessment of left ventricular diastolic filling pattern during the convalescent stage of acute myocardial infarction. Effects of infarct size and coronary thrombolysis.

Pulsed Doppler echocardiography was used to study left ventricular diastolic filling pattern (LVDFP) over the convalescent stage of acute myocardial infarction (AMI) in 25 patients. Twelve normal subjects served as a control group. The patients were divided on the basis of enzymatically estimated infarct size into 2 groups: 7 as the large AMI group, and the other 18 as the small AMI group. Peak early diastolic filling velocity (E) and the ratio of E to peak filling velocity at atrial contraction (E/A ratio) were determined from the Doppler transmitral flow velocity recordings at 1 and 4 weeks after the onset of AMI. At 1 week E and E/A ratio were significantly lower in the small AMI group compared to the control and the large AMI groups, however, there was no significant difference in E and E/A ratio between the control and the large AMI groups. E/A increased with cumulative CK release among the patients (r = 0.54, p < 0.01). In the following 3 weeks E and E/A ratio decreased only in the large AMI group, and E and E/A ratio at 4 weeks weakly correlated with pulmonary capillary wedge pressure (r = 0.63, p < 0.01 and r = 0.65, p < 0.01) and ejection fraction (r = 0.50, p < 0.05 and r = 0.62, p < 0.01) among the patients. There was no significant difference in E or E/A ratio between patients with and without coronary thrombolysis. Thus, LVDFP in the early convalescent stage of AMI was characterized by low E and E/A ratio in patients with small AMI, however, a "pseudonormalized" pattern was observed in patients with large AMI. The effect of the infarct size on LVDFP diminished in the late convalescent stage of AMI. LVDFP in patients with AMI appears to be influenced by the infarct size and by the time of study. The effect of coronary thrombolysis on LVDFP was not evident throughout the convalescent stage of AMI in this study.


Determinants of subsequent late postoperative left ventricular function and reversal of ventricular dilatation after mitral valve replacement for chronic mitral regurgitation.

We studied 16 patients with chronic mitral regurgitation by echocardiography before, and at 3 weeks, at 6-8 months and at 1-9 years after mitral valve replacement (MVR) to investigate serial changes in left ventricular (LV) function and reversal of ventricular dilatation. All patients at an average of 2.6 years after, and 8 patients before MVR were also studied by echocardiography and, except for 3 patients by measuring plasma catecholamines from the right atrium during bicycle exercise. Before operation, all patients were divided into group A (n = 12) with end-systolic dimension (ESD) < 4 cm and systolic blood pressure (SBP)/ESD > 3, and group B (n = 4) with ESD > 4 cm and SBP/ESD < 3. Maximum reduction in end-diastolic dimension (EDD) occurred at 3 weeks in all patients after MVR (from 60.5 +/- 3.7 to 49.0 +/- 4.5 mm, p < 0.05). ESD was reduced significantly (p < 0.5) only in group A. LV function was normal in group A, but it was depressed in group B at early and late periods after MVR. The slopes of the relationship between the mean velocity of circumferential fiber shortening (Vcf) and plasma norepinephrine (NE) during exercise in all patients in group B decreased along with the depression in LV function. After operation, all patients in group A reached New York Heart Association (NYHA) functional class I, while patients in group B were in NYHA class II. It is concluded that the surgical outcome after MVR for chronic MR will be better if preoperative ESD < 4 cm and SBP/ESD > 3. The relationship between mean Vcf and plasma NE during exercise seemed to be a useful index to evaluate the inotropic reserve of the LV.


Plasma atrial natriuretic factor in patients with acute myocardial infarction.

To examine whether atrial natriuretic factor (ANF) is secreted adequately in the early phase of myocardial infarction, plasma ANF concentration and clinical parameters, including hemodynamic variables, were studied in 118 patients with acute myocardial infarction (AMI). The patients were divided into 2 subgroups according to the absence (group A, n = 41) or presence (group B, n = 77) of a history of valvular heart disease, previous myocardial infarction, hypertension, or renal failure. Although no significant difference in atrial pressure after the infarction was found between the 2 groups, the plasma ANF level was significantly lower in group A than in group B (76 +/- 6 vs. 185 +/- 26 pg/ml; mean +/- SEM, p < 0.01). Plasma ANF was correlated with pulmonary capillary wedge pressure in group B (r = 0.54, p < 0.001), whereas no relationship with hemodynamic parameters was observed in group A. In 56 of the 118 patients (group A, n = 18; group B, n = 38), the pulmonary arterial plasma level was significantly higher in group A (p < 0.05), whereas the difference was not significant in group B. Seven of the 8 expired cases among these 56 patients had peripheral plasma ANF levels of more than 150 pg/ml, which were higher than those in pulmonary arterial plasma. These observations suggest firstly that the plasma level of ANF is lower in patients with a new onset of myocardial infarction compared to those with a history of cardiac or renal diseases, and secondly that stimulated ANF release originates not only from the right side of the heart, but also from additional site(s), particularly in patients with chronic ventricle overload and a poor prognosis.


Accuracy and reliability of quantitative measurement of coronary arterial stenosis by videodensitometry on coronary angiogram.

This study was undertaken to investigate the accuracy and reliability of videodensitometry (VDM) in measuring the magnitude of coronary arterial stenosis on coronary angiogram (CAG). CAG taken after administration of sublingual nitroglycerin was analyzed with VDM (XR-70 Coronary Analyzer, Vanguard). The magnitude of stenosis in coronary segments with four different classes of stenosis was consecutively measured 10 times by the same observer, and the values were 89.0 +/- 1.4, 70.9 +/- 2.1, 59.5 +/- 2.5, and 22.8 +/- 3.4%. The coefficients of variation (CVs), indicating intraobserver variability, were low for severe to moderate lesions (1.6, 2.9, and 4.3%, respectively), but was higher for low-grade lesions (14.8%). When the same lesions were measured by 2 observers, the measurements were highly correlated (r = 0.971, p < 0.01). The results of VDM were consistent with those of conventional gross examination for moderate to severe lesions, and the discrepancy was mainly found in low-grade lesions. The magnitude of stenosis of the same lesion was measured from the right and the left anterior oblique views, and the cineangle was found not to affect the results of VDM. Moreover, cardiac cycle did not affect the videodensitometric measurements of % area stenosis. In order to further investigate the accuracy of VDM, the magnitude of stenosis was measured in nine phantom arteries, and the value measured by VDM significantly correlated with the actual stenosis (r = 0.969, p < 0.001). These results indicate that the values of coronary arterial stenosis on CAG measured by VDM are accurate and clinically acceptable, even though variability is somewhat high for low grade lesions. VDM may be useful for evaluation of the outcome of PTCA and the anti-atherogenic action of some agents.


Clinical significance of residual collaterals immediately after successful coronary angioplasty.

The clinical significance of collaterals visible on angiography immediately after successful percutaneous transluminal coronary angioplasty (PTCA) was analyzed in 221 patients who underwent successful PTCA for coronary arteries receiving collaterals. Filling of the collaterals was classified as good; filling the entire epicardial segment of the stenosed site, fair; partially filling the epicardial segments distal to the stenosed site, and faint; visible but not filling the epicardial segments of the diseased vessel. Fifteen of 41 good collaterals remained good or fair on angiography immediately after PTCA. Among the 114 fair collaterals, 26 remained fair and 20 of 66 faint collaterals remained visible on the angiogram immediately after PTCA. There was no relationship between the degree of residual stenosis after PTCA and the degree of residual collaterals. Repeat coronary angiography was obtained in 156 patients. There was no correlation between the presence, absence or degree of collaterals observed on angiography immediately after successful PTCA and the rate of restenosis. Thus, collaterals to the vessels dilated by PTCA often remain on the angiogram immediately after PTCA and are dependent primarily on their degree before dilation. They do not indicate inadequate dilation or predict restenosis.


High prevalence of coronary artery spasm in survivors of cardiac arrest with no apparent heart disease.

The pathogenesis of cardiac arrest in the absence of any apparent heart disease remains unclear. Based on the hypothesis that coronary spasm may be a cause of cardiac arrest in the absence of apparent heart disease, ergonovine testing and/or electrophysiologic studies (EPS) were performed to evaluate the cause of cardiac arrest. Fourteen patients resuscitated from cardiac arrest had no apparent heart disease. A spontaneous episode of angina with ST-segment elevation occurred in 4 patients while under observation. Ergonovine testing was performed in 9 patients, and coronary spasm was induced in 5. EPS were performed in 8 patients, including 3 patients with coronary spasm. No electrophysiologic abnormalities were found in the 3 patients with coronary spasm. Ventricular fibrillation was induced by programmed ventricular stimulation in 2 patients with documented ventricular fibrillation at the time of resuscitation. All but one of the patients with coronary spasm had chest pain preceding cardiac arrest or at least a history of chest pain at rest, while 4 of 5 patients without coronary spasm had no prodromal symptoms. Patients with coronary spasm had a good prognosis when treated with a Ca-antagonist and/or long-acting nitrate. In conclusion, coronary spasm is the most frequent cause of cardiac arrest in cardiac arrest survivors with no apparent heart disease. Ergonovine testing should be performed to evaluate the cause of cardiac arrest when patients have no apparent heart disease.