Myasthenia gravis: quantitative immunocytochemical analysis of inflammatory cells and detection of complement membrane attack complex at the end-plate in 30 patients

To clarify the role of cell-mediated versus humoral immune effector responses in myasthenia gravis (MG), we examined the occurrence of inflammatory cells in muscle from 30 patients with MG, determined the site of accumulation of the cells (at or remote from end-plates), enumerated and immunophenotyped those cells at the end-plate, and evaluated the frequency of deposition of the complement membrane attack complex (MAC) at the end-plate. Seven of 30 patients had well-defined collections of mononuclear cells in muscle (lymphorrhages), but these were not topographically related to the end-plates. Twenty of 30 patients had inflammatory cells (mostly macrophages and T cells) at or near end-plates, but these cells were present at less than 10% of the end-plates, and only seldom was there more than one cell at any end-plate. None of the inflammatory cells penetrated the muscle fiber near the end-plate. All end-plates of all patients immunostained for MAC. The findings reconfirm that the predominant immune effector response in MG is humorally mediated. The lymphorrhages in muscle and other tissues are probably a nonspecific indicator of disturbed immune regulation in MG.

Mechanism of mitochondrial enzyme leakage during reoxygenation of the rat heart

OBJECTIVE

The aim was to clarify the factors that induce enzyme release from mitochondria during anoxia and reoxygenation.

METHODS

Isolated perfused hearts or isolated mitochondria were prepared from hearts excised from rats. The amounts of lactate dehydrogenase, cytoplasmic aspartate aminotransferase, and mitochondrial aspartate aminotransferase released into the coronary effluent from perfused heart preparations were measured. To distinguish the effect of mechanical stress from that of reoxygenation, a latex balloon was placed in the left ventricular cavity to impose mechanical stress and the heartbeat was controlled with a high K+ medium. A digitonin infusion technique was used to obtain only the cytosolic compartment of the cells for analysis of the amounts of mitochondrial enzymes released into the cytosol. The effect of anoxia followed by reoxygenation on enzyme release from isolated mitochondria was studied.

RESULTS

On reoxygenation, mitochondrial aspartate aminotransferase was released as well as cytoplasmic enzymes, but, unlike cytoplasmic enzymes, the release was not influenced by mechanical stress. Mitochondrial injury by reoxygenation depended on the duration of the preceding anoxia. Reoxygenation of isolated mitochondria also induced enzyme release and the presence of ATP in the extramitochondrial space reduced the release of this enzyme.

CONCLUSIONS

Enzyme leakage from mitochondria of myocardial cells occurs during reoxygenation, irrespective of mechanical stress, and this vulnerability to oxidative stress depends on the duration of the preceding anoxic period or the concentration of cytosolic ATP.

Congenital endplate acetylcholinesterase deficiency

Endplate acetylcholinesterase (AChE) consists of globular catalytic subunits attached to the basal lamina by a collagen-like tail. Different genes encode the catalytic subunit and the tail portion of the enzyme. Endplate AChE deficiency was reported previously in a single case (Engel et al., 1977, patient 1). We describe here our observations in four additional patients (patients 2-5). Three cases were sporadic; patients 2 and 3 were sisters. All had generalized weakness increased by exertion but ophthalmoparesis was not a constant feature. All had mild slowing of the pupillary light reflex; other dysautonomic features were absent. None benefited from anticholinesterase therapy. All patients had a decremental electromyogram response; in four of the five patients, single nerve stimuli evoked a repetitive response. Miniature endplate potential amplitude was reduced in patient 5 only. Endplate amplitudes and currents were prolonged but the open-time of the acetylcholine receptor ion channel was normal. In patients 1-4 the quantal content of the endplate potential was reduced due to a reduced number of readily releasable quanta. Quantitative electron microscopy revealed abnormally small nerve terminals, abnormal encasement of the presynaptic membrane by Schwann cells and degeneration of junctional folds and of organelles in the junctional sarcoplasm. Acetylcholinesterase was absent from all endplates of all patients by cytochemical and immunocytochemical criteria. Density gradient ultracentrifugation of muscle extracts from patients 1, 3, 4 and 5 revealed an absence of the collagen-tailed form of the enzyme in patients 1, 3 and 4 but not in patient 5. The kinetic properties of the residual AChE in muscle were normal. Erythrocyte AChE activity and Km values, determined in three patients, were also normal. Studies of the catalytic subunit gene of AChE in patients 2 and 3 revealed no abnormality in those exons that encode the domain to which the tail subunit binds. In patients 1-4 the molecular defect is likely to reside in the gene encoding the tail subunit of AChE, or in a protein necessary to assemble the catalytic and tail subunits. In patient 5, the absence of AChE from the endplate may be due to a faulty tail subunit, a defect in the basal lamina site that binds the tail subunit or failure of transport of the assembled asymmetric enzyme from the cell interior to the basal lamina. The cause of the weakness in these patients is not fully understood but possible mechanisms are discussed.

Effects of interferon-alpha on serum hepatitis C virus in patients with chronic hepatitis C

Interferon is beneficial in some patients with chronic hepatitis C. To assess the efficacy of interferon, we used the polymerase chain reaction (PCR) to measure HCV RNA in serial serum samples from 13 chronic hepatitis C patients who were treated with interferon-alpha. Serum alanine aminotransferase (ALT) values normalized in association with the disappearance of serum HCV RNA in nine cases during the therapy. Serum HCV remained negative after the therapy in the three patients who had no relapse, while serum HCV RNA reappeared in the six patients with elevation of ALT values. The persistence of normal ALT levels appears to be correlated with the clearance of the serum HCV. There were two patients whose ALT became normal immediately after the cessation of interferon. Serum HCV was detectable at the end of treatment when serum ALT was elevated, and thereafter serum HCV disappeared. This result suggests an immunomodulatory effect of interferon in the clearance of HCV in some cases. Furthermore, the semiquantitative PCR assay showed that all five patients in whom ALT values were normal at the end of follow-up without detectable serum HCV genome had lower HCV titers in the pretreatment sera than the other eight patients. The detection of HCV RNA by the PCR assay is useful in determining the efficacy of interferon and its mechanisms.

Clinical application of percutaneous left ventricular support with a centrifugal pump

A percutaneous left ventricular support (PLVS) system can play an important role in the short-term support of patients with severe heart failure, but these devices are not available for clinical use. We devised a new transseptal left atrial (LA) cannula for PLVS without thoracotomy. The cannula is 21 Fr in size (internal diameter: 5.3 mm) and 65 cm in length. This transseptal LA cannula can be inserted easily into the left atrium under fluoroscopy, by the usual transseptal technique, using a conventional Brockenbrough's needle. PLVS was used in two patients who developed cardiogenic shock following acute myocardial infarction and underwent resuscitation using percutaneous cardiopulmonary support (PCPS). The patients could not be weaned from PCPS even after successful percutaneous transluminal coronary angioplasty (PTCA), and PLVS provided 3.0 L/min of assist flow. The duration of PLVS was 114 and 92 hr. Both patients were weaned from PLVS, and one survived. There were no complications related to the PLVS. PLVS with a new transseptal LA cannula may be effective and useful for patients with severe heart failure.

Production of anti-cardiolipin antibody in AKR/J mice with streptozocin-induced insulitis and diabetes

We herein report that anti-cardiolipin antibodies (ACA) were detected in AKR/J mice treated with multiple low doses of streptozocin (STZ)-induced insulitis and diabetes. Daily intraperitoneal (i.p.) injections of 40 mg/kg body wt. of STZ for five consecutive days in the AKR/J mice resulted in hyperglycemia and mononuclear cell infiltrations of islets (insulitis). ACA appeared on day 14, when hyperglycemia began to occur, at a rate of 13.3% (4/30). The rate increased to 83.3% (25/30) on day 21, when diabetes developed, and then fell to 10% (3/30) on day 28. Neither the diabetic AKR/J mice treated with a single high dose of STZ (200 mg/kg body wt.) nor the non-diabetic insulitis free Balb/c mice and B10.S(9R) mice treated with multiple low doses of STZ (40 mg/kg body wt.) produced ACA. The IgG subclass of the ACA belonged mainly to IgG2a. These findings suggest that ACA are produced in association with the development of insulitis, but not induced by either hyperglycemia or STZ.

Growth modulation of human tumor cells by a growth-inhibiting activity derived from tumorigenic V79 Chinese hamster cells

A growth-inhibiting activity was identified in supernatants of the neoplastic V79 Chinese hamster cell line based on its ability to inhibit the proliferation of the same cell line. The partially purified activity, provisionally termed "growth inhibiting factor" (GIF) activity, inhibited the growth of a wide variety of human tumor cells, but not various normal human fibroblasts. This species-nonspecific activity was reversible, saturable, and highly potent in tumorigenic cell lines, and was noted in both monolayer culture and in soft agar. The inhibitory activity of GIF was also exhibited in a chemically defined serum-free medium supplemented with insulin and transferrin. GIF activity was stable to acid, heat, trypsin, and dithiothreitol but sensitive to alpha-chymotrypsin. The pattern of growth modulation by GIF on V79 cells was apparently different from those exhibited by bifunctional peptides such as transforming growth factor-beta, tumor necrosis factor-alpha, and interleukin-1-alpha. In addition, GIF activity cannot be ascribed to these cytokines based on the physicochemical and immunologic properties. Although GIF has yet to be purified to homogeneity, these data suggest that GIF might be a novel growth regulator which has a critical role in regulating growth of V79 cells. The growth modulation of tumor cells by this tumor-derived growth inhibiting activity suggested the presence of an autocrine growth regulatory mechanism even in tumor cells.

Persistent degenerative state of non-pyramidal neurons in the CA1 region of the gerbil hippocampus following transient forebrain ischemia

Morphological changes in the neurons of the gerbil hippocampus following 5 min of forebrain ischemia were examined using light and electron microscopy. Although non-pyramidal neurons in the CA1 region of the hippocampus survived through the full length of the observation period, up to six weeks after ischemia, they consistently demonstrated degenerative changes distinct from those of the well-known "delayed neuronal death" of CA1 pyramidal cells. When examined with the light microscope, CA1 non-pyramidal neurons were found to be shrunken and their nuclei and cytoplasm were hyperchromatic between seven days and six weeks after ischemia. When examined with the electron microscope, postischemic non-pyramidal neurons were found to have markedly electron-dense profiles; their cytoplasm contained numerous free ribosomes and heterogeneous smaller granular substances, the latter also filling the nuclei. However, there was no loss of ribosomes from the rough endoplasmic reticulum, and mitochondrial cristae were preserved, suggesting that these neurons were viable. CA1 non-pyramidal neurons were studied immunohistochemically using three types of monoclonal antibodies, one each against parvalbumin, a nonphosphorylated epitope on the 168,000 mol. wt and 200,000 mol. wt subunits of neurofilament proteins, and microtubule-associated protein 2. CA1 non-pyramidal neurons lost immunoreactivity to these neuron-specific substances six weeks after ischemia, suggesting that these degenerating cells lacked certain types of normal neuronal activity. We conclude that non-pyramidal neurons in the hippocampal CA1 region survive transient ischemia but undergo degenerative changes following complete loss of CA1 pyramidal cells. These changes may be due to depletion of presumptive target-derived trophic factors within the non-pyramidal neurons.

Prognostic significance of bone metastases in patients with metastatic prostate cancer

BACKGROUND

The distribution of bone metastases on a bone scan has not been duly considered when assessing the prognosis of metastatic prostate cancer.

METHODS

The medical records of 76 patients with newly diagnosed, untreated metastatic prostate cancer were reviewed. According to the distribution of bone metastases on the initial bone scan, we divided the patients into three groups: Group I (having bone metastases exclusively within the pelvis and the lumbar spine), Group II (having bone metastases exclusively outside these bones), and Group III (having bone metastases in both areas).

RESULTS

Among the responders to androgen deprivation, those in Group I survived significantly longer than did those in Groups II or III. Because the extent of the disease and the distribution of histologic differentiation in Groups I and II were similar, the results indicate that the presence of bone metastases outside the pelvis and the lumbar spine is predictive of short survival time. This prediction was not possible when the extent of disease (EOD) grading system was used.

CONCLUSION

The distribution of bone metastases on the initial bone scan should be considered as a variable for the prognostic stratification of patients with metastatic prostate cancer.

Pharmacokinetics of beta-methyldigoxin in subjects with normal and impaired renal function

Beta-methyldigoxin (beta-MD) was administered orally (0.2 mg) to 24 patients with various degrees of renal function, to investigate its pharmacokinetic characteristics related to renal function. Serum and urine collected until 120 hours after dosing were assayed for beta-MD and digoxin by high-performance liquid chromatography and fluorescence polarization immunoassay method. The steady-state volume of distribution decreased proportionately as creatinine clearance (CLCR) decreased, although steady-state volume of distribution of hemodialysis patients had large interindividual variability, and their mean value was not different from that of patients with normal renal function. Both renal clearance of beta-MD and digoxin were significantly correlated with CLCR (r = .820, P < .001 and r = .822, P < .01, respectively), and the slope of regression line for beta-MD was only 44% that for digoxin. Significantly reduced urinary excretion of total drug (beta-MD plus digoxin) was shown in patients with CLCR below 50 mL/minute/1.48 m2. This study suggests that the dosage modification is not necessary until CLCR decreases to below 50 mL/minute/1.48 m2, but careful attention should be given in the use of beta-MD in patients with CLCR below this value.

[Coronary artery bypass grafting with all arterial grafts using the internal thoracic, the gastroepiploic and the inferior epigastric arteries]

CABG with all arterial grafts using both the internal thoracic artery (RITA, LITA), the right gastroepiploic artery (GEA) and the inferior epigastric artery (IEA) was performed in 26 patients from July 1989 to August 1991. There were no early and late deaths. Early postoperative coronary angiography in all patients revealed that the best choice of anastomosis was RITA to LAD, LITA to LCX or DIA, and GEA to RCA (type A). All arterial grafts CABG is safe and feasible, but the saphenus vein graft must be used to avoid the anastomosis from small GEA to small LCX.

[5-fluorouracil + low-dose leucovorin and cisplatin sequential chemotherapy with dipyridamole for advanced nonresectable squamous cell carcinoma of the lung: a case report]

A 62-year-old man diagnosed as Stage IIIB advanced non-resectable squamous cell carcinoma of the lung was treated with a sequential combination of 5-fluorouracil (5-FU) and cisplatin (CDDP), with concurrent administration of leucovorin and dipyridamole as a biochemical modulator for 5-FU. After 3 cycles, the mass reduced in size more than 70% in CT scan and the patient underwent a thoracotomy. Histologically, the primary lesion was completely necrotized and of the 10 metastatic regional lymph nodes, only one lymph node contained a small amount of viable cells and 3 additional cycles were conducted. The patient is still alive 30 months after initial chemotherapy. This regimen appears to be potentially useful for non-small-cell lung cancer and warrants further clinical study.

Sarcoid reactions in regional lymph nodes of primary lung cancer

A 66-year-old woman diagnosed as having primary lung cancer with an enlargement of the mediastinal, subcarinal and bilateral hilar lymph nodes underwent a thoracotomy after preoperative chemotherapy. The histological examination showed a moderately differentiated papillary adenocarcinoma in the left upper lobe without any metastases to the regional lymph nodes; however, non-caseous epithelioid granulomas without necrosis were observed in the nodes. These changes were considered to be sarcoid reactions, since no other physiological and laboratory findings compatible with systemic sarcoidosis were observed. The histological findings suggested the possibility that the regional lymph nodes were not involved with the tumor cells at the time of lung cancer diagnosis. Despite the rarity of this condition, sarcoid reactions in the regional lymph nodes must be kept in mind when an enlargement of bilateral hilar lymph nodes is detected in patients with lung cancer, and a good prognosis may be expected in cases with sarcoid reactions in the regional lymph nodes.

Clinical diversity in biliary pancreatitis--classification of two types

One hundred and seven patients with biliary pancreatitis undergoing operation from 1976 to 1989 were reviewed. To clarify the reason for failure to respond to conventional supportive therapy, 73 patients (68%) who underwent emergency surgery were retrospectively divided into two groups according to the severity of the pancreatitis evaluated at laparotomy and compared. Sixty-two had minimal or mild pancreatitis (Group I), among whom 44 (71%) had life-threatening acute biliary tract disease. All underwent biliary surgery and 4 (6%) subsequently died, 2 due to acute obstructive suppurative cholangitis. Eleven had hemorrhagic necrotizing pancreatitis (Group II), among whom 7 had complications of acute pancreatitis such as pancreatic ascites or abscess. These underwent pancreatic and/or biliary surgery and 3 (27%) died of multi-organ failure. There appears to be two types of biliary pancreatitis refractory to conventional supportive therapy, which differ in the extent of surgery required and in mortality: (1) minimal or mild pancreatitis with persistent life-threatening acute biliary tract disease (biliary type), and (2) more severe pancreatitis (pancreas type) early in the course of the disease.

Postoperative recovery of arterial oxygen saturation determined by pulse oximetry in pediatric patients

Small children are physiologically subject to arterial oxygen desaturation. However, few reports have referred to the risk factors related to postanesthetic hypoxemia and the duration of hypoxemia. The purpose of this study was to clarify these two aspects. Eighty-five ASA physical status I infants and children were included in the study. They were scheduled for minor surgery. Fifty-six underwent oral endotracheal intubation, and 29 patients breathed from a mask. Anesthesia was maintained with Enflurane or Halothane and nitrous oxide. Arterial oxygen saturation was measured with a pulse oximeter. The measurements were started shortly after patients' arrival in the recovery room, and conducted every 5 min at least for 1 hour. Ten patients had SpO2 values of less than 95%. In all except one, SpO2 decreased within 10 min after arrival in the recovery room. Age, height, and weight of these 10 children were significantly different from the remaining 75, but there were no significant differences in anesthetic duration and postanesthetic awakefulness between the group with postanesthetic hypoxemia and the one without. The importance of monitoring the clinical condition of pediatric patients after general anesthesia is universally acknowledged. Monitoring with the pulse oximeter has proven very useful and shows that, unless oxygen saturation is monitored, all children should receive supplemental oxygen.

Polymyositis associated with asymptomatic primary biliary cirrhosis

We studied a 67-year-old female who suffered from polymyositis associated with primary biliary cirrhosis (PBC). Liver dysfunction was revealed by a screening test. Antimitochondrial antibodies (AMA) and antinuclear antibodies were positive. Liver biopsy was compatible with PBC (Scheuer stage I). Four years later she showed severe weakness and atrophy on her four extremities. Laboratory examination showed a creatinine kinase level of 312 IU/l, IgM 416 mg/dl, and AMA titer 1:320. Muscle biopsy findings were compatible with polymyositis. Electron microscopic examination disclosed diffuse increase of mitochondria in subsarcolemma and intermyofibrils, which has not been reported until now in polymyositis associated with PBC.

Long-term results of entry closure and aneurysmal wall plication with axillofemoral bypass: a new procedure for repair of DeBakey type 3 dissecting aneurysm

To prevent aneurysm rupture, avoid pseudoaneurysm formation, and preserve intercostal arteries, a new procedure for repair of DeBakey type 3 dissecting aneurysm was developed. Since January 1977, 28 patients have undergone repair of type 3 dissecting aneurysm. Fifteen patients with type 3b underwent this new procedure (group 1) and 13 patients with type 3a dissecting aneurysm underwent segmental graft replacement (group 2). In group 1 a permanent axillofemoral bypass was placed on the right side. Next the intrathoracic false lumen was opened longitudinally, the entry was closed, and the aneurysmal wall was sutured around the true lumen as tightly as possible. The operative mortality rate was 20% in group 1 and 31% in group 2. One of 15 patients in group 1 died of operation-related causes, whereas three patients in group 2 died. There were six late deaths: three in group 1 and three in group 2. Paraplegia occurred in neither group 1 nor group 2. The mean diameter of the plicated descending aorta was 24.0 +/- 2.7 mm 3 months after surgery. No recurrence was detected in group 1. These results suggested that this new surgical technique for repair of type 3 dissection reduces the incidence of paraplegia and pseudoaneurysm formation.

Determination of gliclazide in serum by high-performance liquid chromatography using solid-phase extraction

A simple and sensitive high-performance liquid chromatographic method for a routine assay of gliclazide in serum is described. Serum samples spiked with glibenclamide (internal standard) were applied to Bond Elut C18 cartridges. After washing with phosphate buffer (pH 7.5) and water, the cartridge was eluted with 60% methanol. The eluate was evaporated to dryness. The residue was dissolved in methanol and injected onto an octadecyl silica column (5 microns, 150 mm x 4.6 mm I.D.). The mobile phase was 0.04 M potassium dihydrogenphosphate (pH 4.6)-acetonitrile-isopropyl alcohol (5:4:1, v/v). Ultraviolet detection at 227 nm was used. The minimum detectable level of gliclazide was 20 ng/ml.

Inhibition by 5-fluorouracil of cis-diamminedichloroplatinum(II)-induced DNA interstrand cross-link removal in a HST-1 human squamous carcinoma cell line

To elucidate the mechanism of the synergistic cytotoxicity of 5-fluorouracil (5-FU) and cis-diamminedichloroplatinum(II) (CDDP), we studied the interaction of these agents using a human squamous carcinoma cell line (HST-1). Exposure to 5-FU for 24 h and to CDDP for 1 h produced a 50% inhibitory concentration of 1.0 micrograms/ml (7.7 microM) and 2.5 micrograms/ml (8.3 microM), respectively. The cytotoxic action of CDDP was augmented, and a greater than additive effect was observed when the cells were exposed to 5-FU (1.0 micrograms/ml; 7.7 microM) for 24 h before the CDDP treatment. This synergistic activity was maximal when the interval between 5-FU and CDDP exceeded 24 h. In contrast, the cytotoxicity of CDDP was attenuated when it preceded the exposure to 5-FU. Thymidine did not alter the 5-FU-CDDP interaction. Evaluation of the kinetics of the removal of DNA interstrand cross-links, measured by alkaline elution, showed a significant reduction of this removal in the cells exposed to 5-FU followed by CDDP with a drug-free interval of 48 h, as compared with cells exposed to CDDP alone, or to 5-FU immediately followed by CDDP, although no differences were found in the formation of DNA interstrand cross-links by CDDP among these cells. No significant differences in the accumulation of intracellular platinum were detected by atomic absorption spectrophotometry. These findings suggest that 5-FU modulates the repair of platinum-DNA adducts, thereby potentiating the antitumor activity of CDDP.

[Emergency coronary artery bypass grafting in patients with severe pump failure complicating acute myocardial infarction]

Thirty patients with severe pump failure (Killip's degree III or more) complicating acute myocardial infarction (MI) underwent emergency coronary bypass grafting (CABG). Average age was 66 years old and CABG was performed 2.6 days after the onset of MI. The patients were divided into two groups according to the mechanisms that can bring about severe pump failure: 19 patients had large MI alone (G-I). The other 11 patients had severe ischemia occurring either at areas distant from the site of coronary occlusion or in the previous area at risk (G-II). To estimate the ventricular wall motion quantitatively, the left ventricular wall was divided into 17 segments. Each segment was graded on a four-point scale: akinesis, 3; severe hypokinesis, 2; hypokinesis, 1; normal 0. Wall motion score was estimated by summing the number of asynergic segments score. In G-I, Cardiac index (CI (l/min/m2)) increased from 2.03 +/- 0.91 to 2.68 +/- 0.73 and pulmonary wedge pressure (PCWP (mmHg)) decreased from 28 +/- 5 to 15 +/- 5, 72 hours after the surgery (p < 0.01). In G-II, CI increased from 2.17 +/- 0.78 to 3.17 +/- 1.01 and PCWP decreased from 29 +/- 6 to 13 +/- 5 after the surgery (p < 0.01). There was no difference in preoperative and postoperative hemodynamics between two groups. The wall motion score at the risk area did not change postoperatively (from 16 +/- 7 to 17 +/- 9 in G-I, from 15 +/- 8 to 11 +/- 5 in G-II).(ABSTRACT TRUNCATED AT 250 WORDS)