Isolation and characterization of three lysophospholipases from the murine macrophage cell line WEHI 265.1.

Anion exchange chromatography of WEHI 265.1 cell homogenates resolved the lysophospholipase activity into three peaks, when assayed using lysophosphatidylcholine as a substrate. Peaks 1 and 2 were purified by sequential hydrophobic interaction and gel filtration chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified peaks 1 and 2 indicated homogeneous proteins with apparent masses of 28 and 27 kDa, respectively. Peak 3 lysophospholipases was partially purified by hydrophobic, hydroxyapatite and gel filtration chromatography. Peak 3 lysophospholipase also had calcium-dependent phospholipase A2 activity, which further co-purified with the lysophospholipase activity. The three lysophospholipases were characterized with respect to substrate specificity, additional enzymatic activities and the effects of lipids, metal ions and other compounds on enzymatic activity. Peaks 1, 2 and 3 hydrolyzed lysophosphatidylcholine most readily, but lysophosphatidylethanolamine also served as substrate for each enzyme. Furthermore, all three enzymes hydrolyzed platelet activating factor and acetylated lysophosphatidylcholine. Each lysophospholipase was inhibited by free fatty acids and by palmitoyl carnitine, although the relative sensitivities to these agents differed among the enzymes. The lysophospholipase activities of peaks 1 and 2, but not peak 3, were inhibited by phenylmethylsulfonyl fluoride, diisopropyl fluorophosphate and N-ethylmaleimide. Although they had similar masses, the amino acid compositions of peaks 1 and 2 differed, indicating that these are distinct proteins rather than posttranslational modifications of the same gene product.


Elevated glucose alters A23187-induced release of arachidonic acid from porcine aortic endothelial cells by enhancing reacylation.

Cultured porcine aortic endothelial cells were conditioned in normal (5.2 mM) and elevated (15.6 mM) glucose, prelabeled with [14C]arachidonic acid and stimulated with ionophore A23187. Elevated glucose cultures released less radiolabeled products and less [14C]arachidonic acid. Analysis of cellular lipids revealed that elevated glucose reduced net loss of radiolabel from diacylphosphatidylethanolamine, did not affect early phosphatidylinositol hydrolysis, and increased net loss from diacylphosphatidylcholine and alkenylacylphosphatidylethanolamine. Uptake of radiolabel upon stimulation was examined to measure the role of reacylation on the diminished net release of radiolabel in elevated glucose cultures. Enhanced acylation of [3H]arachidonic acid into cellular lipids, especially PI, was observed in stimulated and resting cultures with elevated glucose. Further, pretreatment of the cultures with an acyltransferase inhibitor, thimerosal, prior to A23187 stimulation in radiolabeled cultures, abolished the effects of glucose on eicosanoid and arachidonic acid release. Differences in the ionophore-induced net loss of radiolabel from diacylphosphatidylethanolamine and phosphatidylinositol of the two glucose treatments were diminished by thimerosal exposure, while net loss of radiolabel from diacylphosphatidylcholine and alkenylacylphosphatidylethanolamine were unaffected. The data indicate that elevated glucose alters deacylation and enhances reacylation of arachidonic acid into endothelial cells and particularly into phosphatidylinositol. Enhanced reacylation may explain some of the altered lipid pathways that have been observed in experiments that elevate glucose concentrations or involve diabetes.


The use of exercise technetium-99m 2-methoxy-isobutyl-isonitrile (99mTc-Sestamibi) perfusion scanning in the detection of acute rejection after cardiac transplantation.

Acute cardiac rejection remains an important cause of death during the first year following cardiac transplantation. Right ventricular biopsies at regular intervals are the main method of detecting rejection, although it is invasive. Unfortunately, non-invasive methods of detecting rejection have not proved reliable enough to replace cardiac biopsies. We assessed the usefulness of technetium-99m 2-methoxy-isobutyl-isonitrile (99mTc-Sestamibi) perfusion scanning in detecting acute rejection in 12 human orthotopic cardiac transplant recipients. Rest and exercise studies and right ventricular biopsies were performed on two occasions. Isotopic evidence of rejection was defined as a perfusion abnormality on either the resting or exercise studies. 99mTc-Sestamibi studies successfully identified acute rejection in 8 of 11 rejection episodes (p less than 0.04). The calculated sensitivity and specificity of 99mTc-Sestamibi scanning were both 72%. Perfusion scanning with 99mTc-Sestamibi may be useful in the diagnosis of acute rejection in cardiac transplant recipients.


Changes in serum testosterone levels after myocardial infarction.

To evaluate the effect of a severe non-endocrine disease on testosterone levels we determined the total testosterone (T), free testosterone (fT), myoglobin and myosin plasmatic levels in 18 men at the time of hospitalization for acute myocardial infarction (AMI), and 1, 3, 7 and 21 days later. Five different methods for determining fT were applied and compared; 1) radioimmunoassay after ultrafiltration, 2) direct analogue based radioimmunoassay (RIA), 3) calculation from total T, sex-hormone-binding globulin (SHBG) and albumin concentrations, 4) calculation from total T, SHBG concentrations with albuminemia fixed at 40 g/L, and 5) evaluation by the (total T)/(SHBG) ratio (fT index). After AMI the total T and fT decreased rapidly (minimum at day 1) and then increased until day 21. While a lower sensitivity in detecting small changes was noted for the direct analogue based fT RIA and for the calculation using a fixed albuminemia, the evolving pattern of the 5 different fT determinations was similar despite different absolute values. However, there was a wide scattering in the results from the different methods used to determine fT. Compared to ultrafiltration, the fT values were lower by direct analogue based assay and higher by calculation. There was a trend of correlation between changes in total T and the maximum myosin concentration (r = 0.557, p = 0.02), showing a relationship between the hormonal changes and the severity of the myocardial infarction.


Evaluation of alkylated derivatives of 99mTc-propylene amine oxime (99mTc-PnAO).

Several lipophilic di-alkylated derivatives of propylene amine oxime (PnAO were complexed to 99mTc. Assessment of the 99mTc-PnAO derivatives included biodistribution and qualitative autoradiography. All of the derivatives studied penetrated the intact blood-brain-barrier, with the 99mTc-dibutyl-PnAO complex exhibiting the lowest initial brain uptake while the 99mTc-diethyl-PnAO and the 99mTc-dipropyl-PnAO complexes possessing nearly identical initial brain uptake as compared to 99mTcPnAO. Qualitative autoradiographs revealed significant loss of image resolution with extended time post injection indicative of rapid radiopharmaceutical washout. Although increasing alkyl chain length did not enhance initial brain uptake, the data demonstrates that limited modification of the PnAO ligand structure can be performed without decreasing cerebral uptake of the respective 99mTc complex.


Conditions for labeling of Schistosoma mansoni cercaria with technetium-99m.

Study of the labeling of Schistosoma mansoni cercaria with technetium-99m (99mTc) at room temperature (25 degrees C) and 37 degrees C shows that the incorporation of radioactivity in this cercaria increases with the increase in stannous chloride concentration, reaching a constant value threshold at 130.00 microM. Strong binding of the 99mTc was obtained since the radioactivity was not washed out. The characteristic motion of the cercaria, labeled at 25 degrees C and 37 degrees C, was only modified at the concentration of 1300 microM for both temperatures, showing that the methodology here described can be applied to living structures. With this technique it is possible to obtain a cercariae suspension labeled with a radionuclide that is very inexpensive and readily available. Furthermore, it is a gamma emitter with a photon energy of 140 keV that would permit one to make scannings of the infected animals and causes less of an environmental impact and present fewer radioactive disposal problems than the long lived radionuclides.


A modeling analysis of rest-stress and stress-rest injection sequences in performing thallium-201 myocardial perfusion scintigraphy.

A new thallium-201 stress testing protocol is proposed in which rest images are obtained prior to stress images. The advantages of the new protocol are that it saves time and requires no special diet or activity restriction between imaging sets. A potential problem from reversing the standard imaging sequence is decreased sensitivity to stress perfusion defects owing to background counts from the rest image. Using a cardiac phantom, 74 sets of stress and rest images were simulated under the new protocol and the standard stress-redistribution-reinjection protocol. Seven observers were asked to classify the images as normal or abnormal and to distinguish ischemic from fixed defects. Differences in observer performances between the two protocols were compared. With the new protocol, observers had sensitivities of 75%-90% and specificities of 100% in identifying a perfusion defect on the stress study. Accuracy was improved if the image counts from the rest study contributed less than 40% of the final counts of the stress study. Detection of ischemic and fixed defects was as good as or better than with standard protocols. Based on the phantom model, rest followed immediately by stress imaging sequence is an advantageous alternative for thallium-201 stress testing. Clinical trials are necessary to further evaluate this new protocol.


Single determination of CA 15.3 and bone scintigraphy in the diagnosis of skeletal metastases of breast cancer.

Single determination of CA 15.3 and bone scintigraphy were performed on the same day as follow-up procedures in 864 patients with breast cancer. The sensitivity and specificity of bone scintigraphy for skeletal metastases were 99% and 88.8%, respectively. The overall sensitivity and specificity of CA 15.3 (cut-off for pathological values greater than 30 U/mL) for cancer recurrence or distant metastases were 69.2% and 92.1%, respectively. The sensitivity of CA 15.3 for bone metastases was lower (69.4%) than that of bone scintigraphy. This was mainly due to the relatively high proportion of false-negative CA 15.3 levels in patients with 1-2 bone metastases (sensitivity = 33.3%). According to this result, the circulating levels of CA 15.3 showed a good correlation with tumor extension and, in patients with bone metastases, with the number of skeletal lesions. As regards the contribution of CA 15.3 to the diagnosis of bone metastases, the demonstration of elevated CA 15.3 values in patients with positive bone scintigraphy could support the diagnosis of skeletal metastases. In fact, the positive predictive value of CA 15.3 in patients with positive bone scintigraphy was significantly higher than with only bone scintigraphy (53.8%) or CA 15.3 (50.4%). Finally, very high values of CA 15.3 in patients with known bone metastases could indicate the presence of visceral metastases (mean CA 15.3 in patients with bone metastases = 125.8 U/mL; mean CA 15.3 in patients with bone and visceral metastases = 420.5 U/mL).


Radioiodinated azomycin pyranoside (IAZP): a novel non-invasive marker for the assessment of tumor hypoxia.

1-(4-Iodo-4-deoxy-beta-L-xylopyranosyl)-2-nitroimidazole (Iodoazomycin Pyranoside; IAZP) was synthesized, labelled with radioiodine(123I, 125I) and evaluated for non-invasive assessment of tumor hypoxia. A biodistribution study with Balb/c mice bearing EMT-6 tumors showed a tumor-to-blood ratio of 13.9, representing 0.5 percent of injected dose per gram of tissue, at 24 hours post injection. This ratio is the highest for any 2-nitro-imidazole reported to date in this tumor model. Rapid elimination of radioactivity from the whole-body was noted (greater than 97% in 24 hours) and thyroid radioactivity at 24 hours was much lower than with other analogues of this series. No toxicity was observed in Balb/c mice at a dose 100 times higher than the anticipated human dose required for scintigraphic imaging. Planar, whole-body gamma scintigraphic images in the murine Balb/c EMT-6 tumor model clearly delineated tumor tissue at 24 hours post injection. These observations suggest that IAZP may be a suitable agent for non-invasive, clinical assessment of tumor hypoxia.


Long-term biodistribution in tumored mice of murine and chimeric B72.3-IgG antibody radiolabeled with 114mIn via both DTPA and a macrocyclic chelator.

To assess the possibilities of using 114mIn as a therapeutic agent, the long-term biodistribution of 114mIn was studied, in tumor-bearing nude mice, after injection of labeled monoclonal antibody (MoAb) B72.3 IgG, either DTPA-coupled murine, DTPA-coupled chimeric, or macrocycle-coupled chimeric antibody. Although the biodistributions in all cases were similar, there were important differences. The use of DTPA-coupled chimeric antibody led to higher concentrations of radioactivity in tumor, and to lower concentrations in liver and bone, as compared to DTPA-coupled murine antibody. The use of macrocycle-coupled chimeric antibody led to higher concentrations of radioactivity in the liver and in bone as compared to the DTPA-coupled chimeric antibody. However, in this case there were no significant differences in tumor uptake or clearance. Radiation doses were calculated based on the organ retention and by neglecting source-to-target contributions. Radiation dose distribution was marginally favorable for therapy in the group injected with DTPA-coupled chimeric antibody.


Pharmacokinetics of indium-111 labeled 10-3D2 antibreast-tumor antibody in patients.

In a program to investigate patient pharmacokinetics of labeled anti-tumor antibodies, a study of the 10-3D2 anti-breast tumor antibody was conducted. The F(ab')2 fragment, coupled with DTPA, was radiolabeled with indium-111 and 1 mg (37 MBq, or 1 mCi) administered to each of 7 patients with documented or suspected breast carcinoma. Abnormal accumulations of radioactivity were observed in only one patient even though 5 had evidence of disease at the time of imaging. Despite the reported absence of circulating antigen to this antibody, sera from one patient showed evidence of a high molecular weight immune complex by size exclusion HPLC. However, this patient had detectable circulating HAMA, which cannot be excluded as the cause of such immune complex. Urine excretion of radioactivity varied greatly from patient to patient (from 2-34% ID within the first day) but the mean value (0.22% ID/hour) was equal to that seen by us in previous studies. The biodistribution of the label was found to be unusual in that kidney levels increased in all patients during the first day and, in particular, liver radioactivity levels decreased in all patients.


[Comparative activities of ciprofloxacin, amoxicillin, and cotrimoxazole in an experimental model of enteritis caused by Salmonella non typhi].

With the use of an in vitro experimental model of enteritis by Salmonella non typhi the efficacy of amoxicillin, cotrimoxazole and ciprofloxacin in the eradication of this fecal pathogen and the prevention of bacteremia was evaluated. Following a fasting period of 48 hours a total of 160 rats were administered 10 UFC of 2 strains of Salmonella non typhi via intragastric tubing. One of the strains was sensitive to amoxycillin and cotrimoxazole (60 rats) and the other strain was resistant to both but was sensitive to ciprofloxacin (100 rats). The antimicrobials were administered 24 hours after the bacterial infection in daily doses for 5 consecutive days. According to the results obtained amoxicillin and cotrimoxazole were ineffective in the eradication of the fecal pathogen indicating an important obstacle in the appearance of bacteremias. To the contrary, ciprofloxacin, even at low doses, eliminated the microorganisms early and demonstrated high efficacy in the prevention of bacteremia in the animals when these results were compared with those of the untreated group.


[HIV infection in an autonomous Spanish community (La Rioja). Features, trends and conclusions applicable to other regions].

The epidemiologic characteristics of HIV infection in La Rioja (Spain) were studied and the future tendencies of the same analyzed. The data from official Health sources were collected and analyzed. In La Rioja, the 5th region in Spain regarding to AIDS incidence, the duplication time of the number of cases continues to shorten. The number in December 1991 was 81. The heterosexual route of infection was 5% of the cases of AIDS up to December 1990 and in 1991 it was 15%, while, with regards to the total number of seropositive subjects, the number rose from 0.3% in December 1990 to 10% in 1991. One thousand one hundred fifty-one seropositive patients were detected in December 1991 representing seroprevalence of 0.34% which reaches 1.14% in the age range between 18-32 years. Mean hospital stay was 23.6 days with 3,032 hospital stays calculated for 1991 representing 8.3 occupied beds/day. There are presently 92 patients undergoing antiviral treatment. Between 43-69 new cases of AIDS have been calculated for 1992. 1) Medical care should be provided to a greater number of seropositive people to avoid early deterioration. 2) The increase in heterosexual infection is alarming. 3) The need for rehabilitation centers for drug abusers and social alternatives to prostitution is clear. 4) Organized campaigns pointing out and returning the dignity and value of life and therewith the role of human sexuality are needed. 5) Alternative means to conventional hospitalization is required.


[Escherichia coli virulence factors causing peritonitis, appendicitis and other extraintestinal infections].

Fifty-nine E. coli strains isolated from clinical cases of peritonitis, appendicitis, cholecystitis, wounds and respiratory infections as well as from other miscellaneous sources were investigated. A control group constituted by 475 E. coli strains isolated from the faeces of healthy individuals were also studied. E. coli O-grouped and investigated for production of cytotoxic necrotizing factor CNF1 and alpha-haemolysin (Hly), expression of P fimbriae and mannose-resistant (MRHA) and mannose-sensitive (MSHA) haemagglutination. Virulence factors significantly associated with extraintestinal strains were: production of CNF1 (19% versus 5%, p < 0.001), Hly (27% versus 9%; p < 0.001) and expression of MRHA (44% versus 16%; p < 0.001). The majority of extraintestinal strains (68% versus 36%; p < 0.001), in contrast with faecal E. coli, belonged to O serogroups frequently detected in uropathogenic and bacteraemic E. coli. These results suggest that E. coli causing different types of extraintestinal infections show similar virulence factors and belong to the same serogroups. However, between E. coli isolated from intraabdominal, wound and respiratory infections the number of strains with virulence factors was lower than in E. coli causing urinary tract infections and sepsis.


[Outbreak of Legionnaires' disease in a private apartment building].

An outbreak of legionnaires disease occurred in Zaragoza (Spain) in an uncommon environment such as a private apartment building was studied. The investigation began upon notification of 3 patients admitted with pneumonia, living in the same apartment building. The suggestion of a common source of infection led to an active search for cases and a micro-environmental study of the zone where the patients lived, as well as a follow up study of other cases with hospital acquired pneumonia throughout the city. Six cases were detected over 9 days with a rate of 1.54%. The evolution of all the cases was favorable. The causal agent was serologically identified as Legionella pneumophilia serogroup 1 which was also found in the shower of one of the patient's bath with further confirmation that the strain isolated belonged to the Pontiac subgroup. The probable source of infection was the potable water. The stagnation, low temperature of the boiler and the under-chlorination of the water are factors which may have contributed to the appearance of this outbreak. The control of this type of outbreak must be based on a specific information system which treats this disease as requiring individualized declaration.


[Isolation of Mycobacterium tuberculosis with primary resistance to chemotherapeutic agents in patients with HIV infection].

To evaluate the resistance of Mycobacterium tuberculosis in subjects with simultaneous infection by the human immunodeficiency virus. Isolation of Mycobacterium tuberculosis was carried out in a University hospital over a period of 7 years with selection of those corresponding to subjects with HIV infection. The isolation of Mycobacterium tuberculosis with resistance to one or more chemotherapeutic drugs was identified and is described herein. A total of 287 subjects were identified having tuberculous disease, 39 (13.59%) of them presented a simultaneous infection by the human immunodeficiency virus. In 4 of the latter (10.26%) Mycobacterium tuberculosis resistant to one or more chemotherapeutic drugs was isolated with the most frequent resistance being to isoniazide (3/4). A high degree of diagnostic suspicion must be maintained in patients with the human immunodeficiency virus with respect to tuberculosis, not only because of frequent endogenous activation but also because of the danger of in-hospital transmission. The possibility of resistance makes systematic antibiograms in these cases advisable. In these patients recommendations regarding treatment should be followed avoiding shortened or simplified therapeutic periods which have occasionally been demonstrated as ineffective.


[Evaluation of a selective medium for the isolation of Moraxella catarrhalis].

The recovery rate of Moraxella catarrhalis in a selective culture medium with acetazolamide and in a conventional blood-agar medium was compared from 1291 samples from the respiratory tract and conjunctivae of children and adults with respiratory and ocular symptomatology. M. catarrhalis was recovered in 215 samples on the acetazolamide medium, and only. 18 cases in the blood agar medium (p < 0.001). The highest recovery of M. catarrhalis was in samples with an accompanying flora, either pathogenic or commensal, such as pharyngeal and nasal exudates. The prevalence of M. catarrhalis in adults and children was 2% and 28%, respectively. We therefore, recommend the use of the acetazolamide medium for the recovery of M. catarrhalis in samples where M. catarrhalis is expected to be present with an accompanying flora.


Physical aspects of the EEG in schizophrenics.

Physical and dynamic aspects of the electroencephalogram (EEG) were evaluated in 12 schizophrenic patients and 12 matched healthy control subjects by means of two descriptive measures proposed by Hjorth (complexity and mobility) and by a nonlinear measure, dimensional complexity. These measures were compared to power spectra analyses. EEG was recorded from frontal, central, and parietal leads under resting conditions (eyes open and eyes closed) for 12 epochs each of 25 sec. Patients showed the expected increased activity in the 1-7 Hz band and, furthermore, a scalp distribution of dimensional complexity and Hjorth complexity opposite to the distribution in controls: in patients dimensional complexity yielded higher values at frontal (Fz) than central (Cz) leads, whereas the resemblance to sinusoidal waveshape (Hjorth complexity) was larger at Fz than Cz. Results indicate more dynamic complexity or variables determining the dynamics of brain processes in frontal areas in patients.


Normalization by nicotine of deficient auditory sensory gating in the relatives of schizophrenics.

Diminished gating of the P50 auditory evoked response to repeated stimuli is a psychophysiological feature of schizophrenia, that is also present in many relatives of patients. Animal models of auditory sensory gating indicate that nicotinic cholinergic neurotransmission is a critical neuronal substrate. The aim of this experiment was to determine if the deficit in sensory gating could be reversed by nicotine administration. Nonsmoking relatives of schizophrenics with abnormal sensory gating were selected as subjects for this initial double-blind trial, to avoid effects of psychotropic medications that might complicate trials in schizophrenic patients themselves. Nicotine-containing gum increased P50 sensory gating to near normal levels within 30 min of administration. The effect was transient; the gating of P50 returned to baseline levels within 1 hr. There was no change observed after placebo administration. In one of the subjects, the anticholinesterase inhibitor physostigmine similarly normalized P50 gating. The results are consistent with the hypothesis that nicotinic cholinergic neurotransmission may mediate a familial psychophysiological deficit in schizophrenia.


Hippocampal formation volume, memory dysfunction, and cortisol levels in patients with Cushing's syndrome.

Patients with chronic hypercortisolemia due to Cushing's syndrome (CS) exhibit cognitive dysfunction. Because glucocorticoid excess is associated with hippocampal damage in animals, and the hippocampus participates in learning and memory, we explored the relationships between hippocampal formation (HF) volume, memory dysfunction, and cortisol levels in 12 patients with CS. After magnetic resonance imaging, HF volume was determined using digital sum of track ball traces of dentate gyrus, hippocampus proper and subiculum, correcting for total intracranial volume. For 27% of the patients, HF volume fell outside the 95% confidence intervals for normal subject volume given in the literature. In addition, there were significant and specific correlations between HF volume and scores for verbal paired associate learning, verbal recall, and verbal recall corrected for full-scale IQ (r = 0.57 to 0.70, p < 0.05). HF volume was negatively correlated with plasma cortisol levels (r = -0.73, p < 0.05). These studies suggest an association between reduced HF volume, memory dysfunction, and elevated cortisol in patients with CS.


Continuous physiological changes and subjective reports in panic patients: a preliminary methodological report.

Six panic disorder patients and six matched control subjects were studied using a new technique allowing continuous and simultaneous monitoring of physiological responses (blood pressure, heart rate, respiration) and subjective reports of anxiety and panic. This was done before, during, and after CO2 inhalation. Panic patients had significantly higher variability in their heart rate, blood pressure, and breathing rate than the control subjects. They also had irregular breathing patterns with frequent pauses. We identified three different patterns of response to CO2 inhalation in the panic patients. Some patients who panicked on CO2 showed a definite association between changes in physiological responses that preceded their subjective ratings of anxiety; however, others did not show this pattern. The possibility of different physiological mechanisms of panic in different patients is discussed.


Cardiovascular phase relationships to the cortical event-related potential of schizophrenic, depressed, and normal subjects.

Cardiovascular phase, especially diastole, influences attention and the event-related potential (ERP) of the right hemisphere of the brain. Depression and schizophrenia are characterized by attentional deficits, unique lateralization of brain function, and deviant phase relationships of biological oscillators. In the present study, the ERP was recorded during stimulation triggered by diastole and systole in control (n = 16), depressed (n = 16), and schizophrenic (n = 9) subjects. Fifty tones were presented and subjects were instructed to count them silently. Previous findings were supported of delayed latencies and increased amplitude in depressed patients and decreased amplitudes and delayed latencies in schizophrenics. An exaggerated effect of diastole on the ERP in the right hemisphere was observed in depressed patients, however, no cardiovascular effect on the ERP was apparent in schizophrenic patients. Results suggested that heart/brain networks are tightly coupled in normal controls, perhaps "overdriven" in depressed patients, and uncoupled in schizophrenics.


Language comprehension in schizophrenics and their brothers.

Disturbances in language functioning may be associated with familial vulnerability to schizophrenia. Language comprehension, measured by the Luria-Nebraska Relational Concepts Factor Scale, was evaluated in 36 schizophrenic probands and their nonschizophrenic adult brothers (n = 41), and in 18 normal controls. Language comprehension performance was a function of psychiatric diagnosis in the brothers. Brothers who met criteria for schizophrenia-spectrum disorders showed significantly reduced language performance compared with unaffected brothers and normal controls. Moreover, abnormal language performance was exhibited by significantly more probands and spectrum-disordered brothers than by the normal controls and the brothers without schizophrenia-spectrum disorders. Finally, language performance was not significantly different for 31 pairs of schizophrenic probands and their brothers. Impaired language comprehension appeared comparatively specific in this sample of relatives, as groups were not significantly different on measures of nonlinguistic concept formation (Wisconsin Card Sorting Test) and general intellectual functioning (WAIS-R Information and Block design). Results suggest that impaired language comprehension is associated with familial vulnerability to schizophrenia, and that this disturbance may be most severe in relatives diagnosed with schizophrenia-spectrum disorders.


The prevalence of autoantibodies among right and left handed schizophrenic patients and control subjects.

Sera from schizophrenic patients (n = 186) and healthy control subjects (n = 346) were tested for the presence of seven common autoantibodies by standard immunological methods. The association between handedness and autoantibodies was tested in a multi-way contingency table using a log-linear model. For men, but not women, nondextrals (patients and controls) were twice as likely to test positive for autoantibodies than dextrals (p = 0.0002). Although more women (33%) than men (24%) tested positive for autoantibodies, handedness was not a distinguishing factor among women. These data suggest that sinistrality and gender are associated with autoantibodies in a subgroup of schizophrenic patients and healthy control subjects.


Hypothalamic-pituitary-adrenal axis function and suicidal behavior in depression.

Hypothalamic-pituitary-adrenal (HPA) axis function was examined in relation to suicidal behavior in depression. There were no significant differences between depressed patients who had or had not attempted suicide for either cerebrospinal fluid concentrations of corticotropin-releasing hormone, plasma cortisol levels predexamethasone or postdexamethasone, or for urinary-free cortisol outputs. However, depressed patients who had made a violent suicide attempt had significantly higher 4 PM and maximum postdexamethasone plasma cortisol levels, and significantly more of them were cortisol nonsuppressors than patients who had made nonviolent suicide attempts. A 5-year follow-up was carried out. There were no significant differences on indices of HPA function between depressed patients who did or did not reattempt suicide during the follow-up or who had never attempted suicide. These results suggest the possibility that dysregulation of the HPA axis may be a determinant of violent suicidal behavior in depression.


Preliminary studies of 6 beta-hydroxydexamethasone and its importance in the DST.

The role of the metabolites of dexamethasone (DEX) in the dexamethasone suppression test (DST) has never been fully elucidated. We report here our preliminary studies of 6 beta-hydroxydexamethasone (6 OH-Dex), a known metabolite of DEX, on the hypothalamic-pituitary-adrenal (HPA) axis of the rat; its activity in the most commonly used radioimmunoassay for plasma DEX; and its plasma concentrations in a normal human subject during the standard 1.0 mg DST. Six OH-Dex administered subcutaneously to rats at a dose of 1 mg/kg was able to completely suppress corticosterone production for at least 3 hr. In the IgG Corp. radioimmunoassay for plasma DEX, 6 OH-Dex was moderately cross-reactive yielding a 50% cross-reactivity of 10%. Gas chromatographic coupled mass spectroscopic analysis of human plasma samples, obtained 12 to 20 hr after the oral ingestion of 1.0 mg DEX, demonstrated similar plasma concentrations for both the parent compound and the 6-hydroxyl metabolite. The relevance of these findings, particularly to pharmacokinetic studies of the DST, is discussed.


Bupropion treatment of fluoxetine-resistant chronic fatigue syndrome.

Chronic fatigue syndrome (CFS) includes many symptoms of major depression. For this reason, many antidepressants have been used to treat the symptoms of this disorder. Among the more recently released antidepressants are fluoxetine and bupropion. In this open study, nine CFS patients who either could not tolerate or did not respond to fluoxetine showed significant response when administered 300 mg/day of bupropion for an 8-week period in both rating of HDRS (t = 4.80, p < 0.01) and BDI (t = 2.48, p < 0.05). Furthermore, bupropion improvement in Hamilton Depression Rating Scale correlated significantly with change in plasma homovanillic acid (HVA) (r = 0.96, p < 0.01). Plasma total methylhydroxyphenolglycol (MHPG) also increased significantly during bupropion treatment (t = 2.37, p = 0.05). Measures of T1 microsomal antibodies also decreased over treatment time; increases in natural killer cell numbers correlated inversely with change in plasma levels of free MHPG (r = -0.88, p < 0.05). Bupropion responders were more likely to have trough blood levels above 30 ng/ml (chi 2 = 3.6, p = 0.05).


[The value of 2- and 3-dimensional computed tomography in the diagnosis and classification of midfacial and orbital fractures].

The value of 2D- and 3D-computed assisted tomography in detecting and classifying midfacial fractures and craniofacial deformities acquired by gunshot injuries was assessed in 123 resp. 26 patients and compared with the postoperative results. In a comparative study 37 patients were prospectively examined by pluridirectional tomography. Examinations of a macerated skull were performed to optimize 3D investigation technique. High resolution CT proved to be the most reliable technique in detecting midfacial fractures and associated soft tissue injuries. 3D-imaging of bony surfaces allowed clear demonstration of fraction extent and fragment displacement without offering additional detail information. 3D-based computer-assisted manufacturing of individual models facilitated surgical planning of complex midfacial injuries.


[Initial experience with digital luminescence radiography in the radiological diagnosis of the visceral cranium].

The purpose of this study was the evaluation of digital luminescence radiography (PCR; Philips Computed Radiography) used in routine radiological analysis of the facial skull. Besides the standard radiographs additional PCR shots were taken in 16 cases. The subjective evaluation was carried out by three different people using clinical criteria. PCR films showed a significant advantage compared to standard radiographs for the above mentioned applications.


[The complication incidence after surgical treatments of mouth, jaw and facial tumors in patients over 70].

After operative therapy of tumors of mouth, jaws and face by patients older 70 years the frequency of complications were 26%. Local and systemic disturbances had nearly similar frequencies. Preexistent diseases, therapeutic concepts and methods of anaesthesia influenced as well frequencies of complications as postoperative lethality. In the analysed group of elderly patients the lethality was unexpected low (2,4%).


[Laser-induced photoacoustic effects in the dentin].

To study photoacoustic effects in dentin caused by UV-laser ablation, laser-induced shockwaves were measured using piezoelectric PVDF films. Above the tissue-specific energy threshold for photoablation the amplitude of the acoustic shock waves is proportional to the applied laser energy density. Laser energy densities of 2 J/cm2 cause pressure amplitudes of 50 bar, densities of 20 J/cm2 cause pressure amplitudes of 1000 bar. To avoid microcracks in dentine the maximum laser energy density to prepare dentin should be limited to approximately 20 J/cm2.


[Light microscopic studies of pulp morphology following orthodontic therapy].

The authors studied the dental pulp morphology and distribution of acid and neutral mucopolysaccharides in teeth subjected to orthodontic therapy. The teeth were moved with a fixed appliance using forces of 60-200 g. Changes in the histological structure of the dental pulp followed the therapy. The number of collagen fibres increased; they were densely packed and formed thick bundles. A certain degree of hyalinization was also observed. The dental pulp cavity was narrowed by apposition of hard tissue deposits along the canal wall. Pulp stones and diffuse calcification were often encountered. The reaction of acid mucopolysaccharides was found to be very weak, sometimes even negative. The reaction of neutral mucopolysaccharides was not affected so markedly. The results of the paper suggest that changes induced in the dental pulp with fixed orthodontic appliances are irreversible and correspond to those of aging. These premature changes together with rapid hard tissue formation, may negatively influence endodontic treatment in the future.


[The assessment of the caries risk in young adults].

Several factors for caries prediction have been proved in a one-year follow-up study on 73 patients. The white-spot lesions have proved to be a good criteria for caries prediction in this population. These lesions could be combined with the microbiological tests Dentocult SM and Oricult N or with the determination of the buffer capacity (Dentobuff), which did not much improve the prediction.


[Clinical comparison of various infusion regimens within the scope of postoperative on demand analgesia with fentanyl].

80 patients (ASA I-III, mean age 40-50 years, mean weight 59-68 kg) recovering from major gynaecological surgery (170-200 min) under balanced anaesthesia were randomly assigned to four groups to self-administer intravenous fentanyl during the early postoperative period. PCA devices were ODAC and Prominject with fentanyl demand doses of 34.5 or 34 micrograms, respectively, and lockout times of 1 or 5 min. Concurrent fentanyl infusion was none (group Prom), fixed-rate with 4 micrograms/h (group ODACf), tail-dose, i.e., a fixed-rate infusion with 17 mg/h for a maximum of 60 minutes following a valid demand (group Prom(t)), or adaptive, starting with 4 micrograms/h and being adapted to individual needs depending on total fentanyl consumption in the latest 60-minute period (group ODACa). Data were collected for fentanyl consumption, venous fentanyl serum concentrations in fixed intervals, actual and retrospective verbal rating pain scores (0-5), haemodynamic variables, respiratory rate, side effects and patients' acceptance. Mean duration of patient-controlled analgesia (PCA) was 15-17 hrs. During this period, an average of 12-18 demands were administered per patient, resulting in an average fentanyl consumption of 36-52 micrograms/h (0.57-0.94 micrograms/kg/h). Analgesic efficacy was good in all groups, mean pain scores ranging from 0.4 to 1.1 (actual) and 1.7 to 2.2 (retrospective). Mean duration of a single fentanyl bolus dose was highly variable, ranging from 58 to 90 min if calculated for the total observation period. Statistically significant differences were found for none of the above mentioned PCA parameters. As a trend, the adaptive-rate infusion strategy was favoured (lowest demand rate, best retrospective pain scores).(ABSTRACT TRUNCATED AT 250 WORDS)


[Lidocaine plus fentanyl for controlling cardiovascular reactions to laryngoscopy and intubation].

Administration of fentanyl or lidocaine alone often insufficiently suppresses the haemodynamic reaction to laryngoscopy and intubation. We therefore evaluated the combination of both substances in patients with good ventricular performance (EF > 60%) undergoing coronary bypass surgery. 20 patients were randomly assigned to Group 1 (G1) or Group 2 (G2). As induction agents flunitrazepam (0.025 mg/kg), fentanyl (6-7 micrograms/kg) and pancuronium (0.1 mg/kg) were used. 3 minutes prior to intubation G1-patients received saline (0.1 cc/kg) while in G2 patients lidocaine (1 mg/kg) was administered. 10 minutes after termination of the preparations for induction (M1), prior to (M2), during (M3) and 10 minutes after the end of intubation (M4) heart rate (HR), blood pressure (MAP), pulmonary artery pressure (PAP) pulmonary capillary wedge pressure (PCWP) and cardiac output (CO) were measured. From these values we calculated rate-pressure product (RPP), total peripheral resistance (TPR), pulmonary vascular resistance (PVR), cardiac index (CI), stroke volume (SV) and stroke index (SI). Whitney-Mann test (U-test) served for statistical evaluation. If compared to baseline (M1), induction of anaesthesia caused in both groups a significant decrease of MAP (G1: 109 to 81 mmHg; G2: 97 to 77 mmHg), CO (G1: 6.2 to 5.2 l/min; G2: 6.6 to 5.2 l/min), CI (G1: 3.3 to 2.8 l/min m2; G2: 3.5 to 2.7 l/min m2) and RPP (G1: 12701 to 10201 mmHg min-1; G2: 11309 to 8070 mmHg min-1).(ABSTRACT TRUNCATED AT 250 WORDS)


[Oral ketamine as preferred preanesthetic medication of uncooperative patients].

We report on oral ketamine for the preinduction of 3 patients who aggressively refused the commonly used induction of anaesthesia, due to young age or mental retardation. One child and two mentally retarded patients aged 30 and 31 years who were to undergo dental surgery aggressively refused the induction of anaesthesia, either by inhalation or rectal, intramuscular, or intravenous application of drugs. One of them previously injured the medical personnel and destroyed the interior equipment of a gynaecologist, who tried to perform an examination. After having received 6 to 8 mg/kg body weight ketamine in 10 ml water, which they accepted well, probably because of the long lasting fluid restriction (about 12 hours), they tolerated the induction of anaesthesia by inhalation (2 patients) or intravenously (1 child). Two patients remained awake, but calm, one fell deeply asleep. After several hours of surgery in inhalation anaesthesia they could be extubated within several minutes and discharged the same day. We conclude that 5 to 10 mg/kg oral ketamine in water which has a bioavailability of approximately 20% is a useful agent for the preinduction of patients who aggressively refuse medical treatment. Because deep sleep states cannot be excluded, we recommend a careful supervision after the application of ketamine. Nevertheless, we could discharge our patients on the same day even after long lasting surgical procedures; this makes this method useful in day case surgery.


Effect of thrombin inhibitors on platelet functions: comparative analysis of DuP 714 and hirudin.

Since thrombin plays an important role in platelet-mediated arterial thrombosis, we have examined the antiplatelet activity of a synthetic thrombin inhibitor, DuP 714 (Ac-(D)Phe-Pro-boroArg), in comparison with that of the naturally occurring inhibitor hirudin. Hirudin was slightly more potent than DuP 714 in inhibiting thrombin-induced aggregation in washed human platelets (IC50s of 72 nM and 150 nM, respectively) and in inhibiting the secretion of plasminogen activator inhibitor-I from human platelets (IC50s of 300 nM and 900 nM, respectively). In contrast, DuP 714 was more potent than hirudin in inhibiting thrombin-induced [125I]fibrinogen binding to gel purified platelets, and in inhibiting thrombin-induced intracellular calcium mobilization in washed platelets. These results indicate that the tripeptide DuP 714 has comparable antiplatelet activity to the 65 amino acid hirudin. We conclude that DuP 714 may have clinical utility in the prevention of platelet-dependent, arterial thrombotic processes.


Autoantibody to plasma fibrinopeptide A in a patient with a severe acquired haemorrhagic syndrome.

We describe a 50-year-old man with a severe acquired haemorrhagic syndrome. He had slightly prolonged clotting times using bovine thrombin, human thrombin and reptilase. His plasma contained a polyclonal IgG which interfered with the generation of fibrin monomers without inhibiting the aggregation of preformed monomers. The inhibitor delayed thrombin-induced fibrinopeptide A release. The IgG bound to insolubilized synthetic fibrinopeptide A (one binding site per molecule) and, with higher affinity, to fibrinogen (two binding sites per molecule). It did not bind to insolubilized fibrin monomers. The IgG did not impair the catalytic activity of thrombin toward a small synthetic substrate but inhibited the binding of thrombin to fibrinogen without binding to thrombin. The binding of the anti-fibrinopeptide A autoantibody to fibrinogen might have impaired thrombin-induced fibrinogen to fibrin conversion in vivo. This may have favoured the reported haemorrhagic syndrome which was associated with severe chronic renal insufficiency.


Platelet prevention of oxidant lung oedema is not mediated through scavenging of hydrogen peroxide.

Previous studies have shown that washed human platelets attenuate oxidant oedema in isolated perfused rabbit lungs through mechanisms dependent on platelet glutathione. We hypothesized that the platelet glutathione redox cycle scavenges hydrogen peroxide in this model and thereby protects vascular endothelial cells from oxidant injury. This hypothesis was tested by asking two questions: (1) do glutathione-supplemented platelets demonstrate augmented lung protection compared with control platelets, and (2) does conjugation of platelet glutathione with 1-chloro-2,4-dinitrobenzene or inactivation of catalase with 3-amino-1,2,4-triazole decrease in vitro platelet metabolism of hydrogen peroxide? We incubated washed human platelets with reduced glutathione or glutathione monoester and observed platelet glutathione contents of 181% and 189%, respectively, compared with control values. Incubation of platelets with N-acetylcysteine did not alter platelet glutathione content. Infusion of glutathione-supplemented platelets into isolated lungs injured by purine and xanthine oxidase did not augment platelet protection compared with untreated platelets. We also found that conjugation of platelet glutathione and/or inactivation of platelet catalase did not decrease the rate constant for platelet metabolism of hydrogen peroxide. We conclude that platelets attenuate oxidant lung oedema through glutathione-dependent mechanisms other than direct scavenging of hydrogen peroxide.


Lupus anticoagulants/anticardiolipin antibodies in patients with normal tension glaucoma.

Ocular vascular occlusive disease resulting in severe retinopathy and/or post-thrombotic glaucoma has been extensively discussed in patients with lupus anticoagulant and/or anticardiolipin antibodies (LA/aCL). Inadequate circulation plays an important role in the pathogenesis of another ophthalmic entity--the normal tension glaucoma. We studied 22 patients with normal tension glaucoma (group I) and 23 with chronic open-angle glaucoma (group II) and compared them with a control group (n = 25, group III). LA, aCL, the aCL cofactor beta 2-Glycoprotein I, and other haemostatic parameters including factor VIII:C, von Willebrand factor, factors II, V, VII and plasminogen activator inhibitor were measured. Five out of 22 (22.7%) in group I, five out of 23 (21.7%) in group II and three out of 25 (12.0%) in group III had positive LA and/or aCL. These prevalences were not statistically significantly different. beta 2-Glycoprotein I was normal in all groups. No other parameters were significantly different between groups. These findings do not support the contribution of ocular microvascular occlusive disease, due to elevated aCL, in the pathogenesis of glaucomatous damage.


Hereditary deficiency of antithrombin III, protein C and protein S: prevalence in patients with a history of venous thrombosis and criteria for rational patient screening.

Data in the literature on the prevalence of hereditary deficiency of the natural coagulation inhibitors are conflicting. We conducted a prospective study on 680 consecutive patients with a history of venous thrombosis to determine the prevalence of hereditary deficiency of antithrombin III (AT III), protein C(PC) and protein S(PS) and to establish selection criteria for rational patient screening. The mean age of the patients at investigation was 44.3 +/- 15.4 years, while that at the first thrombotic event was 38.5 +/- 14.8 years. The total prevalence of inhibitor deficiency states was 48/680 (7.1%). 19/680 patients (2.8%) had AT III-deficiency, 17 (2.5%) PC-deficiency, nine (1.3%) PS-deficiency and three (0.4%) a combined deficiency. In 37/48 deficient patients family studies were performed and the hereditary nature was established in 19 cases (2.8% of total patient population, six with AT III-deficiency, eight with PC-deficiency, four with PS-deficiency and one with a combined deficiency). Family studies in these 19 patients revealed 46 additional individual patients with a hereditary deficiency state. A positive family history was found in 15/19 (79%) with a proven hereditary deficiency state, in 153/619 (25%) of non-deficient patients and in 11/29 (38%) of deficient patients without established hereditary nature. The mean age at the first thrombotic event was significantly lower in patients with a hereditary deficiency state (26.8 years) compared with the other two groups (39.0 and 39.7 years, respectively). In all patients with a hereditary deficiency the first thrombotic event occurred before the age of 45 years.(ABSTRACT TRUNCATED AT 250 WORDS)


Factor XII clotting activity and antigen levels in patients with thromboembolic disease.

Individuals with severe factor XII (FXII) deficiency may be prone to thromboembolic disease and this thrombophilic state may be due to insufficient contact activation dependent fibrinolysis. According to our previous study (Thromb Haemostas 1991; 65: 117-121), however, heterozygous FXII deficiency is not a strong prethrombotic risk factor, only one out of 45 obligatory or possible heterozygotes having sustained a thrombotic event. In the present study, FXII clotting activity (FXII:C) and antigen concentration (FXII:AG) were measured in 200 patients having suffered from idiopathic thromboembolism and compared with the values in 200 healthy controls. Mean FXII levels were not significantly different in thrombophilic patients and controls, and subnormal FXII values were not more frequently encountered in patients than in controls. Specific FXII activity, i.e. the ratio of FXII:C to FXII:AG, showed considerable variation in each of the two groups, but patients and controls had a similar distribution of specific FXII activity. Variations in specific FXII activity were not explained by differences in beta 2-glycoprotein I levels. In conclusion, heterozygous FXII deficiency is not a strong prethrombotic risk factor and subnormal FXII values are not more common in thrombophilic patients than in healthy individuals.


Neutralization of factor X activity by factor X-specific monoclonal antibodies.

Factor X, a vitamin K-dependent protein, is the plasma zymogen for the active serine protease factor Xa. Factor Xa is the proteolytic enzyme for prothrombinase, the multi-protein membrane complex that catalyses the cleavage of prothrombin to thrombin. A panel of 10 monoclonal antibodies (identified by their corresponding clone numbers: 1, 2, 3, 5, 7, 26, 27, 54, 73, and 79) to factor X were produced by immunizing mice with purified factor X. All of the antibodies bound both human factor X and factor Xa in a solid-phase ELISA and binding of the antibodies was not affected by removal of Ca2+ with EDTA. In immunoblot analysis, antibody alpha HFX-54 bound to the light chain and antibodies alpha HFX-1, -5, -7, and -26 bound to the heavy chain of reduced factor X. Antibodies alpha BFX-2b, alpha HFX-27, -54, and -73 prolonged both the factor X-dependent clotting time and activated partial thromboplastin time (APTT) of normal plasma while antibody alpha HFX-1 only prolonged the APTT. None of the antibodies significantly inhibited factor X activation by purified Russell's viper venom factor X activator. In prothrombin activation assays using purified factor Xa, factor Va, prothrombin, Ca2+ and phospholipid vesicles, seven of the antibodies (alpha HFX-1, -3, -26, -27, -54, -73 and alpha BFX2b) showed some inhibition of thrombin generation ranging from 18 to 60% of the control. The decrease in factor X plasma clotting activity was most likely due to inhibition of factor Xa activity in prothrombinase, although some antibody-dependent inhibition of factor X activation may contribute to the observed inhibition of plasma clotting. Prothrombinase activity on platelets was inhibited in an identical manner by the monoclonal antibodies. When prothrombin was activated in the absence of factor Va, only antibody alpha BFX-2b inhibited activation. Calcium-independent determinants on both the heavy chain (determinants 1 and 26) and light chain (determinant 54) of factor X may play a role in prothrombin activation by prothrombinase. Other epitopes (antibodies alpha HFX-3, -27, -73) appeared to be influenced by association of factor Xa with factor Va. Topographic regions on factor X important for factor X activation and factor Xa function may be identified by the use of these monoclonal antibodies.


Enhanced ex vivo proteolysis of plasma von Willebrand factor in disseminated intravascular coagulation.

Plasma levels of von Willebrand factor (vWf) are frequently elevated in patients with disseminated intravascular coagulation (DIC). To investigate the qualitative abnormalities of vWf and the possibility of its ex vivo modification in DIC, we analysed the multimeric composition of vWf in citrated plasma from 15 patients with DIC in the presence or absence of serine protease inhibitors (aprotinin and soybean trypsin inhibitor) and/or cysteine protease inhibitors (leupeptin, N-ethylmaleimide and EDTA). The proportion of large vWf multimers in plasma prepared in the presence of cysteine protease inhibitors was higher than those without such inhibitors. The addition of serine protease inhibitors during the preparation of plasma had no effect on the relative amounts of large multimers. The relative proportion of large multimers in plasma prepared without inhibitors and the difference between plasmas prepared with and without cysteine protease inhibitors correlated with plasma plasmin-alpha 2-plasmin inhibitor complex values, but not with other plasma or serum markers of DIC (platelet count, fibrinogen, FDP, D-dimer or thrombin-antithrombin III complex). We conclude that ex vivo proteolysis of plasma vWf occurs frequently in patients with DIC and cysteine protease inhibitors can protect this degradation.


The effects of type of factor VIII concentrate used in haemophilia on T-helper cell number and inhibitor incidence.

This review surveys the available published data on the impact of the type of factor VIII concentrate infused on T-helper lymphocyte count and factor VIII inhibitor induction in haemophiliacs. While concern has been expressed that certain products may have adverse effects on these parameters, only one trial published to date shows a significant benefit of a high purity product in reducing the rate of CD4 lymphocyte decline in HIV seropositive haemophiliacs. A number of other studies show no such significant benefit although the design of many of these might be criticized and few of them consider the potential impact of viral infection other than HIV, such as hepatitis C. More recent data on the incidence and prevalence of inhibitors in the haemophiliac population suggest that the reported high frequency of inhibitor formation for some products may lie within the expected normal range. This raises interest in why some products appear not to induce inhibitor formation, even in the group of patients at greater risk: multitransfused, severely deficient patients. The occasional reports of late onset high titre inhibitors in multitransfused haemophilia patients associated with the introduction of newer products are a matter of concern.


An overview of current trends in platelet preparation, storage and transfusion.

We present an overview of issues relating to preparation, storage and transfusion of platelet concentrates. The concepts of quality are described and potential benefits from leucodepletion, UVB irradiation and the use of additive solutions discussed. Emphasis is placed on laboratory evaluation of the storage lesion and in particular morphological changes of platelets during storage.


Preparation of platelet concentrates after overnight hold at 20 degrees C.

The clinical demand for platelet concentrates has increased dramatically in the last decade, and poses logistical problems for regional transfusion centres. Pietersz et al. (Vox Sang 1989; 56: 145-150) have shown that it is possible to prepare clinically effective platelet concentrates with substantially reduced white cell contamination, whilst maintaining satisfactory levels of factor VIII:C after holding whole blood at 20 degrees C overnight. This approach offers a method of production that will allow platelet concentrates to be prepared from potentially all donations collected, without resorting to extensive out-of-hours working. Following laboratory evaluation of the procedure we were able to reproduce Pietersz's findings, although hypotonic shock response results were less favourable than observed in our routine platelet concentrates.


Automated processing of leucocyte-poor platelet concentrates.

In view of transfusion reactions and alloimmunization associated with leucocyte contamination of platelet concentrates (PC), there is a general move towards the production of leuco-poor PC. This goal is currently pursued by the production of various PC using buffy coat and apheresis techniques. Although there is no overall consensus on the meaning of 'leuco-poor', by assuming that this refers to a level of 5-50 x 10(7) leucocytes per PC, we were able to make comparisons with available systems used in Europe. In addition to platelet and white cell counts, other markers of PC quality were assessed in some cases. These included traditional markers (such as hypotonic stress response, pH, and lactate and beta-thromboglobulin levels) and newer markers (such as glycocalicin and plasma von Willebrand factor levels). Our preliminary results showed appreciable differences in platelet and white cell content of PC prepared by various types of apheresis equipment. Appreciable differences in the quality of stored PC were also observed between routine PC (non-leuco-poor and buffy coat and apheresed PC (leuco-poor).


The use of mean platelet volume for evaluation of quality of platelet concentrates.

Mean platelet volume (MPV) was determined on whole blood and platelet concentrates (PC) prepared from units of the same blood, as well as on samples of venous blood taken from donors before plateletpheresis and on PC collected by Spectra (COBE Laboratories Ltd) and CS-3000 (Baxter Healthcare Ltd) cell separators. The mean (+/- SD) MPV for PC prepared from blood (7.18 +/- 0.76 fl, n = 12) was significantly lower than that for whole blood (8.32 +/- 0.72 fl, P < 0.02) suggesting significant separation of young, large and dense platelets together with the red cells. In contrast, the mean MPV for PC collected with Spectra and CS-3000 cell separators was 8.48 +/- 0.52 fl (n = 20) and 8.94 +/- 0.60 fl (n = 12), respectively, and was significantly higher (P < 0.01) than that determined in venous blood samples of donors taken before plateletpheresis (7.76 +/- 0.74 fl and 8.12 +/- 0.62 fl respectively). This indicates preferential separation of large platelets, which are by inference, of better quality, into PC.


Glycoproteins Ib and IIb/IIIa in the quality assessment of platelet concentrates during storage.

We have previously shown that levels of soluble glycocalicin (GC) in plasma supernatants derived from units of platelet concentrates (PC) increase progressively during storage. We now report further studies which show that the levels of both microparticle-bound and soluble GC in PC during storage are influenced by exposure of PC samples to EDTA and treatment of PC packs with ultraviolet B (UVB) irradiation. EDTA leads to a significant increase in the release of microvesicle-bound and soluble GC, while UVB irradiation leads to a dose- and rate-dependent increase in GC release. Paradoxically, UVB leads to an unexpected decrease in supernatant levels of von Willebrand factor (vWf) during storage which contrasts with its increase in untreated, stored PC. Moreover, an increase in GC release during storage is associated with a corresponding decrease in platelet size as determined by measurement of mean platelet volume (MPV) in citrated PC. The GC release is significantly correlated with standard platelet functional tests and other new generation tests such as dMPV and supernatant levels of vWf. In addition, preliminary results show the presence of microparticle-bound and soluble glycoprotein (Gp) IIb/IIIa in the supernatant plasma of stored PC. Our results suggest that supernatant levels of GpIb, GpIIb/IIIa, and vWf, together with alteration in MPV, provide essential new informative parameters for quality assessment of PC.


Platelets as immunogens.

An immune response to human platelet antigens (HPA), as in neonatal alloimmune thrombocytopenia (NAIT) and post-transfusion purpura (PTP), is the exception rather than the rule and evidence is accumulating for the importance of human leucocyte antigen (HLA) class II restriction in this situation. Platelets have only HLA class I antigens and do not cause primary HLA alloimmunization; in platelet transfusions this is due to the contaminating leucocytes. Autoimmune thrombocytopenia is more common than the alloimmune conditions. The main target antigens for platelet autoantibodies are glycoproteins (Gp) IIb/IIIa and Ib/IX. The mechanism of drug-induced immune thrombocytopenia has been re-examined in relation to the target cell orientation of the antibody and of the drug.


An audit of the use of platelet concentrates in the prophylaxis of thrombocytopenic haemorrhage in a large haematology unit.

Platelet transfusions are valuable in the prevention of thrombocytopenic bleeding in patients undergoing chemotherapy for haematological malignancies. The commonly used threshold platelet count for transfusion of 20 x 10(9)/l was established in the 1960s when the clinical situation was very different from today. Review of the use of platelet concentrates in a large haematology unit showed lack of adherence to this threshold with the use of platelet transfusions at higher platelet counts. Major bleeding episodes occurred at counts above the threshold when additional clinical factors were operating. A lower threshold was therefore recommended and instituted. This resulted in a 20% reduction in the use of platelet concentrates with no increase in major bleeding episodes.


The alloimmunized patient: effective transfusion support and newer experimental approaches.

Refractoriness occurs in a proportion of patients who receive multiple platelet transfusions. Alloantibodies, in particular those directed against the class I human leucocyte antigens (HLA) present on the platelet surface, are frequently associated with accelerated platelet destruction and transfusion failure. Compatible platelets for transfusion may be found by selecting donations from HLA-typed individuals, crossmatching patients' sera against donor lymphocytes and platelets or both. Maintaining a large panel of HLA-typed apheresis donors is expensive and some mismatching is inevitable due to the polymorphic nature of the HLA system. Cross-matching may improve the outcome when HLA-matched donations are transfused and may also be a cost-effective strategy for the selection of compatible untyped platelets. Administration of intravenous immunoglobulin, plasma exchange and ex vivo removal of platelet HLA have been employed successfully in a few refractory alloimmunized patients but do not yet have an established role. Experimental studies in animal models suggest that it may be possible to induce tolerance to HLA and prevent alloimmunization.


Thrombotic thrombocytopenic purpura.

Thrombotic thrombocytopenic purpura is an uncommon disorder, but it continues to be of considerable interest. The disease mechanisms are unclear and the aetiology is unknown. Perhaps most enigmatic of all, the mode of action of plasma therapy, which successfully induces remission in about two-thirds of cases, is wholly inexplicable. There are currently several areas of debate on the subject of thrombotic thrombocytopenic purpura. This paper addresses these points of contention: the definition of the disease, its distinction from haemolytic uraemic syndrome, the nature of the platelet aggregating factors in the plasma of patients with acute disease, the importance of the abnormalities of von Willebrand's factor observed in the acute and quiescent phases of the disease, the nature of the factor in normal plasma that induces remission, and the possible causes of the observed superiority of plasma exchange combined with plasma infusion, over plasma infusion alone.


Disseminated intravascular coagulation and hepatocellular necrosis due to clove oil.

We describe the case of a 2-year-old child who suffered from disseminated intravascular coagulation (DIC) and hepatocellular necrosis, following ingestion of clove oil. The patient was treated with heparin and fresh frozen plasma, and, following specific haemostasis assays, with appropriate coagulation factor and inhibitor concentrates. The case demonstrates how this approach can be successfully used in the management of DIC with coexisting liver failure.


Platelet imipramine binding is increased in essential thrombocythaemia.

A decrease in platelet serotonin content is well recognized in myeloproliferative disorders, although the basis for this is unclear. The relationship between decreased platelet serotonin and the number of serotonin transport channels in the platelet membrane was explored indirectly by measuring the number of the closely associated imipramine binding sites. Imipramine binding parameters were determined in 12 patients suffering from either essential thrombocythaemia or polycythaemia rubra vera and in 10 healthy controls. The maximal number of imipramine binding sites (Bmax) was increased in both patient groups, significantly so in those suffering from essential thrombocythaemia. This increase contrasts with a decrease in binding in other conditions known to be associated with decreased platelet serotonin. This study thus demonstrates a discrepancy in terms of reduced platelet serotonin content and increased imipramine binding on platelets from patients suffering from essential thrombocythaemia. It is suggested that further investigation of the imipramine binding site in these disorders, in parallel with measures of platelet serotonin content and uptake, is warranted.


Meningococcaemia in an adult with hereditary C4b-binding protein deficiency: study of the variations of the protein S system.

Serial studies of the plasma protein C-protein S system were performed during the clinical course of a pregnant woman with meningococcaemia who recovered under therapy. The patient had limited purpura fulminans skin lesions and hereditary C4b-binding protein deficiency was suspected. This diagnosis was confirmed in the patient 1 year after delivery and also by family studies. During the meningococcaemia, an initial mild and transient acquired protein C deficiency was seen but no protein S deficiency was observed despite consumption of the latter protein. As C4b-binding protein partial deficiency is associated with high free protein S and protein S activity, this may have protected against acquired protein S deficiency during meningococcaemia.


Sociologic aspects of pregnancy.

Increasingly, social factors are recognized as having a major impact on pregnancy, childbearing, and prenatal care. This review examines some of the more recent societal developments that have influenced health care for pregnant women. Although human gestation is a biologic phenomena, it exists with the social context of personal needs, family, and community of the pregnant women. This social fabric determines the perception, management, and outcome of that gestation. Significant influences to examine include pregnant women in the work force; malpractice concerns of health care providers; issues related to the cost of health care in pregnancy; the legal rights of the pregnant woman versus the legal rights of the fetus; pregnancy and occupational health; and the role of stress in pregnancy outcome.


Drug supplementation in pregnancy.

Since antiquity, there have been references in medicine to the role of nutrition in pregnancy outcome. Reviewing articles on nutrition and drug supplementation in pregnancy, one is struck by the variety of remedies that have been tried and the variety of effects that have been attributed to them. The number of herbal remedies that have been touted is astounding, and the entire science of Geophagia evolved in the hope identifying of those population-specific customs that may have had a positive effect on birth outcome as an adaptive mechanism. Most recently, there has been renewed interest in the role of nutritional and drug supplementation in pregnancy, specifically in the areas of pregnancy-induced hypertension and teratogenesis. In this article, I briefly review the role of drug supplementation in pregnancy, ranging from established needs such as iron to prevent iron-deficiency anemia to the controversies of low-dose aspirin supplementation for the prevention of preeclampsia and preconceptional folic acid supplementation for the prevention of neural tube defects.


Breech presentation and shoulder dystocia in childbirth.

This review covers the recent literature relevant to breech presentation and shoulder dystocia. Further evidence in favor of external cephalic version at term has emerged, and the possibility of its use in women with previous cesarean section has been suggested. Attention has been given to trial of labor in selected cases of term breech presentation. The evidence to guide the method of delivery for preterm breech presentations remains inadequate. No perinatal differences have been demonstrated among the outcome of breech second-born twins delivered by external cephalic version, breech extraction, or cesarean section. The evidence in favor of elective cesarean for suspected macrosomia to prevent shoulder dystocia is unconvincing for nondiabetics and is doubtful for pregnant diabetics. The McRoberts maneuver for shoulder dystocia has not received the prominence that it deserves.


Anesthesia and analgesia for labor.

Epidural analgesia remains the mainstay for providing pain relief during labor. The search continues to find the ideal combination of analgesic agents and administration techniques that will provide excellent pain relief for the mother yet minimize side effects to the mother and fetus. This article reviews recent studies of epidural analgesia, including the increased use of epidural opioids, patient-controlled epidural analgesia, and the complications of epidural analgesia (including effects on gastric emptying, maternal temperature control, and hemodynamic changes to the mother and fetus). Intrathecal (spinal) analgesia, especially using opioids, is also discussed.


Puerperium and breast-feeding.

The issues related to breast-feeding and problems of the puerperium are often obfuscated by the general but outdated practice of recommending cessation of lactation. This article examines recent literature (June 1991 to May 1992) on breast-feeding and the treatment of puerperal problems, emphasizing that breast-feeding may be maintained during virtually all treatment modalities. Additionally, the use of drugs to support or suppress lactation has been of interest, and the increased attention to the fertility impact of breast-feeding, breast-feeding and maternal health, and human immunodeficiency virus and breast-feeding has resulted in several new articles of note. In general, the recent study of breast-feeding has identified many positive side effects, while other articles confirm that the treatment for retained placenta, postpartum pain, and puerperal infection, as discussed in recent literature, do not contraindicate breast-feeding.


Delivery room management and outcome issues in the neonate.

Issues relevant to term newborns include screening for functional neurologic deficits that may be improved by early detection and intervention. Papers are presented that consider ocular, acoustic, and cognitive evaluations in the term neonate. Delivery room management of the meconium-stained infant remains controversial and is discussed by several authors. Data are presented regarding intubation and its role in the prevention of meconium aspiration syndrome, causes of meconium passage in utero, and its significance for neonatal outcome. In addition, illicit drug use, especially cocaine, is a significant problem among pregnant women with multiple sequelae for the fetus and newborn. Papers reviewed include a comparison of neonatal drug screening techniques, fetal effects of subacute maternal cocaine use, and follow-up data in a large cocaine-exposed cohort. The impact of the cocaine problem is growing nationally, overwhelming existing programs for medical care and rehabilitation, and mandating change at all levels of intervention. Finally, the search for a definitive indicator or predictor of birth asphyxia continues to generate literature in both the pediatric and obstetric journals.


Trends in obstetric and gynecologic residency education.

Residencies in obstetrics and gynecology are popular with graduating medical students, especially women, and positions are filled in excess of 100%. New Accreditation Council for Graduate Medical Education special requirements have focused on several clinical areas and require demonstration of scholarly activity by faculty and 24-hour in-house faculty coverage. Other issues of current concern are resident work hours, pregnancy among residents, and training of residents in induced abortion.


Sexual abuse of children and adolescents.

Clinicians are seeing greater numbers of children and adolescents suspected of being sexually abused. In the past, the interpretation of the medical findings was hampered by a lack of knowledge of normal anatomy and genital flora in the nonabused prepubertal child. The quality of more recent studies has been improved by the use of more appropriate controls and by the thorough evaluation of reportedly normal girls to ensure that they are truly nonabused. Such studies have provided the clinician with more accurate medical data with which to support the diagnosis of child sexual abuse.


Adolescents and human immunodeficiency virus infection.

As of March 31, 1992, individuals 13 to 19 years of age had been diagnosed with acquired immunodeficiency syndrome; over one third were diagnosed in the past 2 years alone. Because of the long incubation period from initial infection to acquired immunodeficiency syndrome diagnosis, the majority of young adults with acquired immunodeficiency syndrome were probably initially infected as adolescents. In 1991, 34% of adolescents with acquired immunodeficiency syndrome were female, and their predominant mode of transmission was heterosexual contact. Human immunodeficiency virus seroprevalence studies of adolescents show a male-to-female ratio approaching 1:1, with many human immunodeficiency virus-infected adolescent women identifying none of the standard risk. Factors such as sexual and drug experimentation, risk taking, and sense of invulnerability so characteristic of adolescence put adolescents at special risk for human immunodeficiency virus. There is no published information on if or how clinical manifestations of human immunodeficiency virus disease in adolescents might differ from those seen in adults. Medical care should be broad-based and should include access to clinical trials for new drug treatments. General knowledge levels about acquired immunodeficiency syndrome are high among US adolescents, but behavioral changes have lagged behind. All adolescents should be targeted for intensive education about human immunodeficiency virus along with interventions designed to enhance their general coping, communication, and decision-making skills.


Update on pregnancy, condom use, and prevalence of selected sexually transmitted diseases in adolescents.

Adolescent pregnancy and its consequences continue as major sources of morbidity in the United States. A teenager who becomes a parent is at a significant disadvantage in becoming a contributing adult, both psychosocially and economically. The physician who cares for adolescents has the responsibility of helping parenting teens to find needed support so that they will be able to overcome this significant hurdle. Attention from public agencies has focused on increasing condom use as one approach to adolescent pregnancy prevention. The major advantage of using condoms is that they also prevent transmission of sexually transmitted diseases. Of note is that level of knowledge about condoms is not related to their use, and engaging in high-risk behaviors is related to a decreased likelihood of condom use. With rates of condom use estimated at less than 50%, rates of sexually transmitted disease remain high, as reported in recent surveys.


Pediatric and adolescent gynecologic endocrinology.

Best described as a transformation from the infantile state to an accentuated dimorphic adult state, puberty is a sequence of events characterized by the secretion of gonadal hormones leading to the development of secondary sexual characteristics, gametogenesis, and reproductive function. In girls, the first signs of puberty may be evident at age 8, with the process largely completed by age 16; in boys, puberty commonly begins between ages 10 and 12 and is largely completed by age 18. Adrenarche, the secretion of adrenal androgens, starts between ages 6 and 8 and is clinically accompanied by pubarche. Premature pubarche should be diagnosed as either typical or atypical. In atypical premature pubarche, corticotropin testing is recommended to determine nonclassical adrenal enzyme deficiency of steroidogenesis. Children with either type of premature pubarche should be under continued follow-up throughout puberty. The trigger of the onset of puberty is still unknown. The presence of gonadotropin activity and possible circadian rhythm in the prepubertal years allows for new understanding in possible triggering mechanisms of puberty. Precocious puberty, which is associated with significant psychologic implications and possible pathology, must be categorized as complete precocious puberty with activation of the hypothalamic-pituitary axis or incomplete precocious puberty without activation of the central axis as effective therapies are so different. The categorization does not yield diagnoses, as there are multiple etiologies within each category. The treatment of central precocious puberty with gonadotropin-releasing hormone agonists will postpone pubertal progression to a more appropriate age.(ABSTRACT TRUNCATED AT 250 WORDS)


Structural anomalies of the reproductive tract.

Structural anomalies of the female reproductive tract may be divided into disorders of lateral fusion and disorders of vertical fusion of the Müllerian duct system. In the past, these disorders were diagnosed at or after menarche or later in life during evaluation of various forms of reproductive tract failure, such as infertility and pregnancy wastage. Newer techniques including pelvic ultrasound and magnetic resonance imaging have allowed diagnosis in the pediatric patient and on occasion, even in utero. Surgical correction of lateral-fusion defects (didelphic, bicornuate, septate, and unicornuate uteri) have remained essentially unchanged except for surgical reconstruction of the septate uterus. Surgical correction of vertical defects (vaginal septi and cervical agenesis or dysgenesis) has received considerable recent interest with the development of newer techniques that may be more effective than the reconstructive procedures of the past.


Assessment and management of premenstrual syndrome.

Premenstrual syndrome has recently become the subject of more rigorous scientific scrutiny. As a result, techniques exist for accurate diagnosis, and the pathophysiology of the disorder is less mysterious. At present, the disorder is thought to be the caused by the interaction of cyclic changes in estrogen and progesterone with a variety of systems, particularly neurotransmitters. Serotonin appears to play an especially important role in this regard. Increased understanding of premenstrual syndrome has enabled the development of specific treatment modalities that, unlike previous prescriptions, have demonstrated efficacy in rigorous and reproducible studies.


Chronic pelvic pain.

Chronic pelvic pain is a common and important gynecologic problem. The causes are diverse but can usually be categorized by the astute clinician. Gynecologic causes can often, although not always, be pinpointed for specific management protocols. Highlights of helpful areas are described in terms of history, physical examination, and laboratory and endoscopic diagnosis. Therapy may be medical, surgical, psychologic, or supportive. If specific, treatment is likely to be effective in some patients whereby a cause cannot be found, yet the patient may be helped. Some patients improve without treatment.


Reversible contraception for the woman over 35 years of age.

Methods of reversible contraception, oral contraceptives, intrauterine devices, and Norplant (systemic progestin-only contraceptive; Wyeth-Ayerst, Radnor, PA), can be used for women over 35 years of age. Oral contraceptive formulations are safe and effective for healthy women up to the age of menopause. Oral contraceptives in women who do not smoke cigarettes do not result in a significant increased risk for cardiovascular disease. The incidence of breast cancer is not increased in women who have used oral contraceptives. A slight increase was found in younger women who had been on oral contraceptives based on a reanalysis of the contraceptive and steroid hormone study of the Centers for Disease Control. A reduction in the incidence of ovarian epithelial neoplasia by 40% was found in three European case-control studies. Two intrauterine devices are currently available on the US market: Paragard (GynoPharma, Somerville, NJ) and Progestasert (Alza Corp., Palo Alto, CA). Both of these provide highly effective contraception. A World Health Organization prospective randomized study found that there was an increase in pelvic inflammatory disease rates in the first 20 days after intrauterine device insertion. The intrauterine device itself did not increase the pelvic inflammatory disease incidence rates. The Norplant system exerts its contraceptive action through ovulation inhibition and alteration of cervical mucus. The major consumer complaint is irregular or prolonged uterine bleeding, which can be controlled by oral estrogen.


Breast disease.

Breast cancer is the leading cause of death in women between the ages of 35 and 54. It is estimated that the specialist in obstetrics and gynecology provides health care for more than half of the female population in the United States and should become familiar with both benign and malignant breast conditions. Confronted with the misconception that the disease appears in women "at risk" only and the estimate that one in every nine women born in the United States will develop breast cancer, adequate education, screening, examination, and documentation are essential in the field of breast disease.


Hormone replacement therapy.

Although hormone replacement therapy (HRT) has been available for almost 100 years, conflicting opinions still exist about its efficacy and safety. There is uniform agreement that vasomotor instability and vaginal atrophy are totally reversible with HRT. Effective treatment of bone loss with HRT depends on the number of years of estrogen deprivation, peak bone mass, and rapidity of bone loss. Oral, transdermal, and pellet estrogens are equality effective. Mortality from coronary heart disease decreased 20% to 40% in women on HRT, yet the mechanism has not yet been ascertained. The increased risk of endometrial cancer has been confirmed, but better diagnostic techniques for detection in the precancerous state have been developed. The relationship of breast cancer to estrogen use has not been conclusive. Meta-analysis of 13 studies results in a relative risk of 1.06, whereas a large case-control study reveals a relative risk of 0.9. However, it is clear that in the average, healthy woman, low-dose estrogen replacement for less than 10 years does not increase the risk of breast cancer. Physicians are encouraged to help patients weigh the risks and benefits of HRT.


Transvaginal sonography in gynecologic office practice.

Recent technologic developments have made transvaginal ultrasound an important adjunct to gynecologic examination in both the office and the emergency room settings. Important advantages of using transvaginal ultrasonography to supplement bimanual examination are presented and discussed. Training and equipment issues, as well as medicolegal issues, are addressed.


A prospective study of pyrogenic reactions in hemodialysis patients using bicarbonate dialysis fluids filtered to remove bacteria and endotoxin.

Pyrogenic reactions (PR) are a well-recognized complication of hemodialysis and have been associated with dialyzer reuse, high-flux dialysis, and bicarbonate dialysate. However, the roles of bacteria and endotoxin in dialysate for producing PR are not well defined. To determine the effect of removing most bacteria and endotoxin from the dialysate on the incidence of PR, a cohort of chronic hemodialysis patients receiving high-flux, high-efficiency, or conventional hemodialysis at three centers with bicarbonate dialysis fluids that had been filtered with a polysulfone high-flux hemodialyzer was prospectively studied. Unfiltered bicarbonate concentrate had median bacterial and endotoxin concentrations of 479,000 CFU/mL and 39,800 pg/mL, respectively. After filtration of the bicarbonate concentrate at the central proportioner, dialysate had a median 9.2 CFU/mL of bacteria and 17.8 pg/mL of endotoxin. Dialysate filtered at individual proportioning dialysis machines had a median 0.001 CFU/mL of bacteria and 0.19 pg/mL of endotoxin. Nine PR were identified among 303 patients after 28,007 hemodialysis treatments (0.3 PR/1,000 treatments). The rate of PR was similar for the three hemodialysis treatment modalities and for first-use compared with reused dialyzers. Although the PR rate in this study was lower (P = 0.046) than the PR rate of a previous study with unfiltered dialysis fluids (0.7 PR/1,000 treatments), it represents a difference of only 10 PR in over 28,000 treatments. It was concluded that filtration of hemodialysis fluids is efficacious in removing bacterial and endotoxin contamination and can result in a lower incidence of PR in patients receiving high-flux, high-efficiency, or conventional hemodialysis.


Short- and long-term efficacy of total parathyroidectomy with immediate autografting compared with subtotal parathyroidectomy in hemodialysis patients.

A retrospective study was performed in chronic hemodialysis patients comparing total parathyroidectomy (PTX) followed by immediate autografting (IA) (total PTX+IA) with subtotal parathyroidectomy (subtotal PTX). One hundred six patients with severe, uncontrolled hyperparathyroidism were referred to this center and underwent surgery during the period from 1980 to 1990. Long-term follow-up after PTX was available in 49 of them: 28 patients had total PTX+IA and 21 had subtotal PTX. The two surgical methods were evaluated with respect to preoperative severity of hyperparathyroidism, immediate postoperative results, and long-term parathyroid status, as evaluated by an RIA measuring intact immunoreactive parathyroid hormone (intact iPTH; normal values, 15 to 65 pg/mL). The initial degree of hyperparathyroidism was comparable in the two groups. An excellent short-term control of hyperparathyroidism was achieved in the great majority (95%) of patients with either surgical procedure. However, long-term normalization of parathyroid gland activity was achieved in only one third of patients whereas 33% had elevated intact iPTH levels (> 130 pg/mL; i.e., higher than twice the upper range of normal) and 32% had low intact iPTH levels (< 15 pg/mL), consistent with permanent hypoparathyroidism. No difference was found in the immediate failure rates: 0 of 28 cases after total PTX+IA compared with 2 of 21 cases after subtotal PTX. Similarly, long-term intact iPTH levels were comparable: 400 +/- 105 versus 212 +/- 82 pg/mL (mean +/- SE; P = not significant). Interestingly, long-term serum intact iPTH levels were higher in patients with nodular (N = 18) than with diffusely (N = 26) hyperplastic glands: 556 +/- 146 versus 126 +/- 52 pg/mL (P < 0.001) and recurrence of hyperparathyroidism was more frequent with nodular hyperplasia (11 of 18) than with diffuse hyperplasia (4 of 26) (P < 0.02). In conclusion, although excellent short-term results were obtained with both procedures, satisfactory long-term control of parathyroid gland function was achieved in only one third of the patients, the other two third remaining either hypoparathyroid or developing recurrent hyperparathyroidism. Last, the histological subtype of parathyroid glands was partially predictive of the recurrence of hyperparathyroidism.


Effect of vitamin B6 supplementation on plasma oxalate and oxalate removal rate in hemodialysis patients.

Whether pyridoxine (B6) supplements decrease plasma oxalate concentrations in patients on maintenance dialysis is unresolved. The effect of two dose levels of B6, 0.59 mmol/day (100 mg/day) over 6 months and 4.43 mmol (750 mg) after each dialysis treatment for 4 wk, on plasma oxalate and oxalate removal rate (dialysis plus urinary excretion) was studied in patients on maintenance hemodialysis. In both studies, a control group unsupplemented with B6, who remained on their regular diet, was also studied. The vitamin B6 status of the patients was assessed by the erythrocyte glutamate pyruvate transaminase activity and index before and during supplementation. No decrease in plasma oxalate or oxalate removal rate was found in either study. The plasma oxalate and oxalate removal rates of the unsupplemented hemodialysis patients were not different from those receiving B6 either before or after supplementation. These studies demonstrate that high-dose B6 supplementation does not decrease plasma oxalate concentration in a population of hemodialysis patients.


Treatment of childhood nephrotic syndrome.

This review examines selected aspects of the treatment of the nephrotic syndrome in children. Particular attention has been paid to two groups of nephrotic children. First, children with steroid-responsive nephrotic syndrome are discussed. Recently, a series of controlled studies have provided important information regarding the optimal duration of steroid therapy. Initial episodes of the nephrotic syndrome are best treated with "long" courses of prednisone therapy (6 wk of high-dose daily prednisone followed by 6 wk of alternate-day prednisone). In contrast, relapses do as well with "short" courses (about 2 wk of daily prednisone and 2 wk of alternate-day therapy). Some children who are steroid responsive require high doses of prednisone to remain in remission. These patients may require alkylating agent therapy. The most common cause of steroid-resistant nephrotic syndrome is focal segmental glomerulosclerosis. Over the past 10 yr, these patients have been treated with an intensive protocol involving multiple infusions of high-dose methylprednisolone and, in many cases, oral alkylating agent therapy. Current experience with this treatment is presented. The protocol appears to improve the outcome in children with focal segmental glomerulosclerosis, although it is believed that it is essential that these observations be confirmed by a controlled trial. There is also interest in the use of angiotensin-converting enzyme inhibitors and cyclosporine in the treatment of childhood nephrotic syndrome. The experience with these agents is briefly reviewed, but the current data are inadequate to indicate their role(s) in this condition.


Glycosyl-phosphatidylinositol-anchored membrane proteins.

Many proteins of eukaryotic cells are anchored to membranes by covalent linkage to glycosyl-phosphatidylinositol (GPI). These proteins lack a transmembrane domain, have no cytoplasmic tail, and are, therefore, located exclusively on the extracellular side of the plasma membrane. GPI-anchored proteins form a diverse family of molecules that includes membrane-associated enzymes, adhesion molecules, activation antigens, differentiation markers, protozoan coat components, and other miscellaneous glycoproteins. In the kidney, several GPI-anchored proteins have been identified, including uromodulin (Tamm-Horsfall glycoprotein), carbonic anhydrase type IV, alkaline phosphatase, Thy-1, BP-3, aminopeptidase P, and dipeptidylpeptidase. GPI-anchored proteins can be released from membranes with specific phospholipases and can be recovered from the detergent-insoluble pellet after Triton X-114 treatment of membranes. All GPI-anchored proteins are initially synthesized with a transmembrane anchor, but after translocation across the membrane of the endoplasmic reticulum, the ecto-domain of the protein is cleaved and covalently linked to a preformed GPI anchor by a specific transamidase enzyme. Although it remains obscure why so many proteins are endowed with a GPI anchor, the presence of a GPI anchor does confer some functional characteristics to proteins: (1) it is a strong apical targeting signal in polarized epithelial cells; (2) GPI-anchored proteins do not cluster into clathrin-coated pits but instead are concentrated into specialized lipid domains in the membrane, including so-called smooth pinocytotic vesicles, or caveoli; (3) GPI-anchored proteins can act as activation antigens in the immune system; (4) when the GPI anchor is cleaved by PI-phospholipase C or PI-phospholipase D, second messengers for signal transduction may be generated; (5) the GPI anchor can modulate antigen presentation by major histocompatibility complex molecules. Finally, at least one human disease, paroxysmal nocturnal hemoglobinuria, is a result of defective GPI anchor addition to plasma membrane proteins.


Five-lipoxygenase products in glomerular immune injury.

Leukocyte infiltration, proliferation, and activation are central pathogenetic components of immune injury in the glomerulus. Initial cellular infiltration by polymorphonuclear leukocytes (PMN) is a consequence of the deposition of immune complexes at discreet sites in the glomerulus. This is often followed by macrophage/monocyte infiltration, as well as proliferation of resident mesangial macrophages. Activated leukocytes constitute a rich source of lipid-derived bioactive autacoids, in particular, oxygenated metabolites of arachidonic acid. Here, we assess the role of the five-lipoxygenase (5-LO) family of eicosanoids, in particular, leukotrienes D4 and B4 (LTD4 and LTB4) in mediating functional and structural deterioration during immune inflammatory reactions in the glomerulus. LTD4 and other peptidyl LT appear to play a central role in the reductions in GFR in the acute phases of injury by virtue of their potent vasoactive properties, in particular, their capacity to reduce the glomerular capillary ultrafiltration coefficient, likely through contraction of smooth muscle elements in glomerular mesangial cells. The latter cells possess specific receptors for LTD4 in both humans and rat and contract in vitro when exposed to LTD4 after receptor-mediated activation of phospholipase C. LTB4, a nonvasoconstrictor LT, is released in the early phases of immune injury, likely from leukocyte sources as well as from transcellular metabolism of its precursor, LTA4, by the enzyme LTA4-hydrolase in glomerular mesangial and endothelial cells. LTB4, a potent promoter of PMN attraction, adhesion, and activation exacerbates glomerular functional impairment and structural damage by amplifying PMN-dependent mechanisms of injury. In their totality, 5-LO products of arachidonic acid contribute to the impairment of the normal glomerular filtration and sieving functions that attend acute inflammatory injury in the renal glomerulus and to the subsequent progression of glomerular destruction. This is high-lighted by the significant degree of protection afforded by the selective inhibition of arachidonate 5-LO in vivo in acute and chronic models of experimental glomerulonephritis.