Urinary excretion of podocalyxin indicates glomerular epithelial cell injuries in glomerulonephritis

Immunofluorescent study of urine sediments was performed to detect glomerular epithelial cell injuries using specific monoclonal antibody against podocalyxin, a glycoprotein that is prominently expressed on glomerular epithelial cells. Three kinds of structures (casts, granules and cells) were stained in urine sediments from various glomerular diseases. The presence of podocalyxin in urines was confirmed by absorption test, immunoelectron microscopy and Western blotting. Podocalyxin was detected in the urinary sediments of patients with various forms of glomerulonephritis, particularly those with acute onset. The amount of their urinary excretion apparently indicates the degree of the glomerular epithelial cell injuries in glomerular diseases.

Plasma plasminogen activator inhibitor-1, tissue plasminogen activator and serum lipoprotein(a) after reperfusion therapy in acute myocardial infarction: comparison between sequential and direct percutaneous transluminal coronary angioplasty

To determine which reperfusion therapy for acute myocardial infarction (AMI) is advantageous to avoid subsequent thrombotic coronary occlusion, 8 patients with AMI were studied. Four of them (group S) underwent sequential PTCA following unsuccessful intracoronary thrombolysis and the others (group D) direct PTCA. Serial changes in plasma plasminogen activator inhibitor-1 (PAI-1), plasma tissue plasminogen activator (t-PA) antigen and serum lipoprotein(a) levels were compared between the two groups. In group S, plasma PAI-1 levels showed no significant serial change after PTCA. However, in group D, plasma PAI-1 levels increased significantly 4-24 h after PTCA. We suggest that more attention should be focused on the prevention of thrombotic coronary closure as well as mechanical abrupt occlusion after direct PTCA.

Potent protective effect of melatonin on in vivo paraquat-induced oxidative damage in rats

The in vivo effect of melatonin on paraquat-induced oxidative damage in rat lung and liver was studied using two parameters: the concentration of malonaldehyde and 4-hydroxyalkenals as indices of lipid peroxidation; changes in total and oxidized glutathione. Melatonin (10 mg/kg) or an equal volume of saline were administered intraperitoneally (ip) to rats 30 min prior to an ip injection of paraquat (20 mg/kg or 70 mg/kg). After paraquat treatment, the animals received melatonin or saline ip injections every six hours for 24 hours. Rats were killed 24 hours after paraquat injection. In lung, both the low and high dose of paraquat, when administered with saline, augmented lipid peroxidation (100% and 18%, respectively) above levels found in control animals. Treatment with melatonin completely reversed this effect. In liver, paraquat (70 mg/kg) increased lipid peroxidation by 40% over the levels of control animals. The increase was completely abolished by treatment with melatonin. Paraquat at 20 mg/kg did not induce any significant change in liver lipid peroxidation. Paraquat treatment resulted in a significant decrease of total glutathione concentration and increased oxidized glutathione in both lung and liver. These effects were abolished by treatment with melatonin. The results suggest that melatonin confers marked protection against paraquat-induced oxidative toxicity in both the lung and liver.

Renal lesion of type Ia glycogen storage disease: the glomerular size and renal localization of apolipoprotein

In order to investigate the glomerular size and renal localization of apolipoprotein in type Ia glycogen storage disease, a renal biopsy was performed in two proteinuric patients. Histopathological examination of the biopsy specimens revealed focal sclerotic glomerular sclerosis in both patients. The mean glomerular area was 21.6 +/- 11.6 x 10(3) microns 2, indicating enlargement of the glomeruli. Immunohistochemical staining of the specimens for apolipoprotein showed localization of apolipoprotein AI on the inner side of the glomerular capillary wall, and in proximal tubular epithelial cells. In one patient with a history of several episodes of hypoglycemia, treatment with corn starch improved the carbohydrate and lipid metabolic profile and reduced the daily urinary protein excretion from 2.23 to 0.5 g. These results suggest that focal sclerotic glomerular lesions associated with type Ia glycogen storage disease may be related to disorders of carbohydrate and lipid metabolism.

Pseudomonas stimulates interleukin-8 mRNA expression selectively in airway epithelium, in gland ducts, and in recruited neutrophils

Neutrophils may play important roles in chronic airway diseases. Pseudomonas is a common pathogen in some chronic airway diseases, and expression of the neutrophil chemoattractant interleukin-8 (IL-8) is induced by Pseudomonas in various cells in vitro. Here we examine the localization of IL-8 mRNA expression after incubating human and dog bronchi with Pseudomonas supernatant in vitro. To examine IL-8 expression in recruited neutrophils, we also superfused the dog bypassed tracheal segment with Pseudomonas supernatant in vivo and measured neutrophil number and IL-8 concentration in luminal fluid; simultaneously, we introduced Pseudomonas supernatant by catheter in a peripheral airway. After 6 h, we analyzed IL-8 mRNA expression and localization in removed tissue. Unincubated bronchi showed no IL-8 mRNA expression, but incubation with Pseudomonas supernatant in vitro resulted in IL-8 mRNA expression in surface epithelial, gland duct, and a subpopulation of serous gland cells. In vivo, introduction of Pseudomonas supernatant into dog trachea and peripheral airways caused IL-8 mRNA expression in epithelial and gland duct cells but also in the recruited neutrophils. Pseudomonas lipopolysaccharide alone was without effect in vitro and in vivo. We conclude that Pseudomonas products, but not lipopolysaccharide, stimulate IL-8 expression in airways and that this expression occurs primarily in surface epithelial and gland duct cells, thus bringing the chemoattractant to the bacterial site. Furthermore, IL-8 expression in recruited neutrophils provides a potential mechanism for positive feedback of this protective antibacterial response.

Exercise performance in children with hyperthyroidism

An attempt was made to define exercise performance in children with untreated hyperthyroidism using treadmill stress testing. Data were obtained for five female patients and the results were compared with those obtained for 16 normal female subjects. There were no significant differences at rest between the hyperthyroidism group and the control group in oxygen uptake, minute ventilation and respiratory rate. On the other hand, heart rate in the hyperthyroidism group was significantly higher than that in the control group. During exercise, there were significant differences between the two groups in oxygen uptake, heart rate, minute ventilation and respiratory rate. Hyperthyroid patients did not show an abrupt increase in heart rate during the first 30 s of exercise. Exercise stress testing can therefore reveal cardiopulmonary abnormalities that are not evident at rest in children with hyperthyroidism.

Treatment of severe myoclonic epilepsy in infants with bromide and its borderline variant

We studied the efficacy of bromides (BR) as add-on therapy in 11 patients with severe myoclonic epilepsy in infants (SME) and in another 11 with the borderline variant of SME (BVSME). Study subjects were aged 8.5-183 months (mean 64.4 months). Longest duration of BR treatment was 37 months (range 4-37 months; mean 19.7 months). Eight of 22 (36%) of patients with generalized tonic-clonic seizures (GTCS) had an excellent effect (> 75% reduction in total seizure frequency or duration) and 9 (41%) had a moderate effect (50-75% reduction) 3 months after introduction of BR. Twelve months after initiation of BR. 5 of the patients with significant improvement were no longer responsive; ultimately, therefore, 6 had an excellent effect and 2 had a moderate effect. Of those with partial seizures (n = 5) and myoclonic/absence seizures (n = 5), only 1 patient in each group showed a moderate effect at the 12-month time-point. Dosages and serum concentrations of BR ranged from 30 to 100 mg/kg (mean 58 mg/kg) and from 64 to 159 mg/dl (mean 101 mg/dl), respectively. Of the 12 patients experiencing side effects, including drowsiness, appetite loss, and skin rash, 1 required a reduction in BR dosage because of an extensive acneiform rash on the face. The results show that BR treatment holds promise for patients with SME and BVSME and should therefore be investigated further.

Effect of interferon therapy in a patient with chronic active hepatitis type C associated with interstitial pneumonia and rheumatoid arthritis: a case report

Interferon (IFN) is widely used to treat patients with chronic hepatitis types B and C but has been found to occasionally aggravate rheumatoid arthritis (RA) or cause interstitial pneumonia. We administered 6 MIU/d IFN-beta by intravenous injection for 6 weeks to a 55-year-old man with chronic active hepatitis type C associated with RA and interstitial pneumonia. Transaminase levels rapidly returned to normal after treatment and hepatitis C virus-RNA (nested RT-PCR method) was negative on completion of treatment. No significant adverse reactions or aggravation of RA or interstitial pneumonia occurred. These findings suggest that use of IFN-beta in the treatment of patients with chronic hepatitis type C associated with RA and/or interstitial pneumonia presents no problem if appropriate precautions are taken.

Role of integrins in melanocyte attachment and dendricity

Integrins are a family of proteins known to mediate attachment of cells to extracellular matrix materials. The substratum specificity and cation dependence of specific integrin heterodimers have been extensively characterized, and to a lesser degree specialized roles in cell attachment versus dendricity have been defined in some cell types. In the past decade, melanocyte attachment rate and morphology have been found to have strong substratum dependence, suggesting a major role for integrins in these processes. In order to investigate this aspect of pigment cell biology, human newborn melanocytes were subjected to flow cytometry analysis and plated on a variety of substrata under conditions known to promote or block the binding of specific integrin pairs. Melanocyte attachment to laminin and type IV collagen was promoted by Mg2+ and Mn2+ but not by Ca2+, in the range of concentrations examined. However, dendrite outgrowth from melanocytes already attached on laminin or type IV collagen was promoted by Ca2+ to a far greater degree than by Mg2+, and Mn2+ had no effect on dendrite outgrowth. Flow cytometry analysis revealed that melanocytes expressed beta 1, alpha 2, alpha 3, alpha 5, alpha 6 and alpha v integrin subunits as well as the alpha v beta 3 heterodimer. The influence of substratum on the profile of integrin expression was minimal, but alpha 6 and beta 1 integrins were observed by confocal microscopy to be expressed over the entire cell surface, while alpha 2, alpha 5 and alpha v beta 3 integrins localized along dendritic processes or at their tips. In accordance with the implications of these distribution patterns, anti-beta 1 and anti-alpha 6 integrin monoclonal antibodies blocked melanocyte attachment to laminin, while anti-alpha 2, anti-alpha 5 and anti-alpha v beta 3 inhibited dendrite outgrowth but did not block substratum attachment on either laminin or type IV collagen. On the basis of these data and the known characteristics of integrin molecules, we conclude that melanocyte attachment to laminin is mediated primarily by alpha 6 beta 1 integrin in a Ca(2+)-independent, Mg(2+)- and/or Mn(2+)-dependent manner, while dendrite outgrowth on laminin and type IV collagen requires extracellular Ca2+ and is mediated by alpha v beta 3 as well as alpha 2 and alpha 5 integrins.

Expression and function of Fas antigen and bcl-2 in human systemic lupus erythematosus lymphocytes

Studies indicate that autoimmune phenomena might be caused by a failure to eliminate autoreactive lymphocytes. Therefore, we examined Fas antigen and bcl-2 expression and function in lymphocytes from human systemic lupus erythematosus (SLE) patients. Freshly isolated lymphocytes from patients with active SLE expressed more Fas antigen than did lymphocytes from patients with inactive SLE or from normal controls. They also showed characteristic DNA fragmentation after treatment with anti-Fas antibody. Expression of bcl-2 in T cells from active SLE patients was significantly higher than that in cells from inactive SLE patients and from normals. These data suggest that lymphocytes in patients with active SLE maintain an activated state in vivo. However, the role of Fas and bcl-2 expression in the regulation of lymphocyte survival in SLE is still unclear and further investigations concerning the role of these molecules in autoimmune phenomenon in SLE are needed.

Enhancement by propofol of the gamma-aminobutyric acidA response in dissociated hippocampal pyramidal neurons of the rat

BACKGROUND

Activation of the gamma-aminobutyric acidA (GABAA) receptor-ionophore complex has been reported as a possible molecular mechanism of the anesthetic action of propofol. Augmentation of GABA-induced inhibitory transmission has also been suggested as a mechanism. Because data describing this latter mechanism in mammalian neurons are few, we have examined the effects of propofol on the GABA response in central neurons of the rat.

METHODS

Hippocampal pyramidal neurons were dissociated after enzyme treatment of the rat brain slices. The neurons were voltage-clamped with the whole cell configuration of the patch clamp technique. Neurotransmitters and drugs were applied using the "Y-tube" method, which exchanges the extracellular solutions around the neuron within 10-20 ms and makes it possible to obtain the peak response before desensitization develops.

RESULTS

In pyramidal neurons voltage-clamped at -60 mV, GABA induced an inward current. Propofol (10(-6) M) augmented the current and shifted the concentration-response curve for GABA to the left without affecting the maximum response. A low concentration of the anesthetic (10(-6) M) reduced the dissociation constant for GABA from 8.2 x 10(-6) to 4.2 x 10(-6) M without a significant effect on the Hill coefficient. Coapplication of propofol at a higher concentration (5 x 10(-6) M) also shifted the GABA dose-response curve to the left, reducing the dissociation constant to 2.8 x 10(-6) M. Potentiation by propofol was not associated with a change in the reversal potential for the GABA response and was not voltage-dependent. The inhibitory glycine response was not affected by propofol (10(-6) M or 5 x 10(-6) M).

CONCLUSIONS

Propofol at clinically relevant concentrations enhances the inhibitory GABAA receptor-mediated response in mammalian central neurons. The enhancement may result in reduced excitability of the neuronal network and may, consequently, contribute to the anesthetic action of the agent.

Inhibitory effect of melatonin on cataract formation in newborn rats: evidence for an antioxidative role for melatonin

We evaluated the inhibitory effect of melatonin, a recently discovered scavenger of free radicals, on cataract formation in the newborn rat. The glutathione synthesis inhibitor, buthionine sulfoximine (BSO) (3 mmol/kg), was intraperitoneally injected into newborn rats for 3 consecutive days starting on day 2 after birth. These glutathione depleted rats develop cataracts. Melatonin (4 mg/kg) was injected intraperitoneally into half of the rats once a day beginning at day 2 after birth; the other half of the animals received solvent daily. The incidence of cataract was observed on day 16, after the eyes of the newborn animals had opened. Both reduced glutathione (GSH) and oxidized glutathione (GSSG) levels were measured. Cataracts were observed in all animals (18/18) treated with BSO plus solvent. The incidence of the cataract in the animals cotreated with melatonin was only 6.2% (1/15). Total lenticular glutathione (GSH + GSSG) levels in BSO only treated rats were reduced by 97%. The total glutathione in the lens of the BSO plus melatonin group was significantly higher (by 3%) than that of the BSO only group. The percentage of the total glutathione as GSSG for the BSO plus solvent group was higher than the control value. Cotreatment of BSO injected rats with melatonin (4 mg/kg/day) clearly reduced cataract formation proving that it is directly or indirectly protective against oxidative stress which accompanies glutathione deficiency. The inhibitory effects of melatonin on cataract formation in this study could be due to melatonin's free radical scavenging activity or due to its stimulatory effect on glutathione production.

Pattern Matching and Discourse Processing in Information Extraction from Japanese Text

Information extraction is the task of automaticallypicking up information of interest from an unconstrained text. Informationof interest is usually extracted in two steps. First, sentence level processing locates relevant pieces of information scatteredthroughout the text; second, discourse processing merges coreferential information to generate the output. In the first step, pieces of information are locally identified without recognizing any relationships among them. A key word search or simple patternsearch can achieve this purpose. The second step requires deeperknowledge in order to understand relationships among separately identified pieces of information. Previous information extraction systems focused on the first step, partly because they were not required to link up each piece of information with other pieces. To link the extracted pieces of information and map them onto a structuredoutput format, complex discourse processing is essential. This paperreports on a Japanese information extraction system that merges information using a pattern matcher and discourse processor. Evaluationresults show a high level of system performance which approaches human performance.

Increased endothelin-1 production in fibroblasts derived from patients with systemic sclerosis

OBJECTIVES

To determine whether fibroblasts from patients with systemic sclerosis (SSc) produce excessive amounts of endothelin-1 (ET-1), which is recognised as having vasoconstrictive properties and as having a potent mitogenic effect on fibroblasts.

METHODS

Dermal fibroblasts were removed from 11 patients with SSc and from five normal controls (NC). The assay of ET-1 protein was measured by an ELISA that used two anti-ET-1 antibodies. The gene expression of prepro ET-1 mRNA was evaluated by a reverse-transcriptase polymerase chain reaction (RT-PCR) method.

RESULTS

Levels of ET-1 protein were significantly higher in SSc fibroblast cultures than in those of normal fibroblasts (p < 0.01). The expression of prepro ET-1 mRNA was also higher in SSc fibroblasts than in normal fibroblasts. The addition of interleukin-1 beta (IL-1 beta) increased the production of ET-1 by fibroblasts.

CONCLUSION

The findings indicate that the overproduction of ET-1 is a novel abnormal function in SSc fibroblasts, and that ET-1 induced by fibroblasts may play a role in the fibrosis and Raynaud's phenomenon of SSc.

Intracytoplasmic granulofilamentous inclusion bodies in a meningioma. Immunohistochemical and ultrastructural studies

A case of cerebellar tentorial meningioma, with abundant, large, eosinophilic intracytoplasmic inclusions, was studied immunohistochemically and ultrastructurally. These intracellular inclusions were periodic acid-Schiff negative and ultrastructurally appeared as a condensation or aggregation of numerous intracytoplasmic intermediate filaments. These inclusions were not related to microvillus-lined ductules, indicating that these inclusions were distinct from pseudopsammoma bodies. In addition, these inclusions were intensely immunopositive for vimentin, whereas staining for glial fibrillary acidic protein, epithelial membrane antigen, cytokeratin, neurofilament, desmin, actin, or type IV collagen was negative. To our knowledge, this is the second reported case of meningioma with such unusual inclusions, but the first one to demonstrate that the intracytoplasmic intermediate filaments and their related inclusions were mainly composed of vimentin.

Cultured murine dermal cells can function like thymic nurse cells

We have established a dermal fibroblast-like stromal cell line, DFB-1, and a clone, 12E2, from epidermal sheets prepared from the skin of BALB/c mouse ears by trypsin digestion. They were suggested to be fibroblasts or myofibroblasts, as 1) they were polygonal or spindle-shaped under the phase-contrast microscope, 2) they did not possess any tonofilaments or desmosomes, and 3) they did not express any marker for bone marrow-derived cells or macrophages. Interestingly, these cells showed a unique phenomenon of "pseudo-emperiporesis," which was first recognized in the interaction between thymic nurse cells and thymocytes. Namely, two T-cell clones and one T-cell hybridoma migrated beneath the cytoplasmic projections of the fibroblast-like cutaneous stromal cells in culture. Furthermore, secretion of interleukin 7 by these cells was confirmed by bioassay using an IL-7-dependent cell line and by inhibition with anti-interleukin 7 antibody, and the expression of interleukin 7 mRNA was also demonstrated in these cells by a combination of reverse-transcriptase polymerase chain reaction and Southern blot analysis. These data strongly suggest the presence of unique stromal cells even in the skin, probably at the upper dermis, which can function like the nurse cells in the thymus. These stromal cells may play a crucial role in cutaneous immunophysiology.

HCV-marker-positive autoimmune-type chronic active hepatitis: a possible relation between HCV infection and liver autoreaction

This study focused on 32 patients who were diagnosed as having autoimmune hepatitis based upon clinical and histological factors. Fifteen of these patients were positive for HCV-RNA and for one of the HCV-related markers tested, including anti-C100, ELISA II, and RIBA 2 (Group 2). The remaining 17 patients were negative for all HCV-related markers (Group 1). Clinical factors in the two groups, including the frequency of autoantibodies, serum levels of aminotransferase and gammaglobulin, HLA phenotypes, and the response to corticosteroid treatments, were compared. The titer of serum anti-nuclear antibodies and the level of serum aminotransferase at initial diagnosis were significantly higher in Group 1 than in Group 2. Furthermore, the genetic background of the two groups, as indicated by HLA phenotypes, differed. All cases in Group 1 were HLA-DR4-positive, whereas only 60% of those in Group 2 cases had HLA-DR4. Also, all cases in Group 1 but only 66.7% of the cases in Group 2 showed good clinical responses to corticosteroid treatment. Finally, no cases of HCV-related-marker-positive autoimmune hepatitis (Group 2) had antibodies for LKM, suggesting that these cases were clinically different from type II autoimmune hepatitis. These data indicated that immunosuppressive treatment might be the preferred initial treatment in patients who either satisfy the criteria for AIH or who are sero-positive for an HCV-marker.

Characteristics of porcine coronary artery endothelial cells in culture: comparison with aortic endothelium

In the present study we compared the characteristics of porcine coronary artery endothelial cells in culture with the characteristics of aortic endothelium. Morphologically, coronary artery endothelial cells were larger than aortic endothelial cells. Under basal culture conditions, both coronary artery and aortic endothelial cells secreted significant amounts of prostacyclin and endothelin-1. The outstanding findings is that coronary artery endothelial cells secreted larger amounts of endothelin-1 than aortic endothelial cells. Immunofluorescence staining revealed that individual endothelial cells synthesize both substances. This comparative study provides important evidence indicating that the characteristics of coronary artery endothelial cells differ from those of aortic endothelial cells.

Gliclazide directly suppresses arginine-induced glucagon secretion

To clarify whether the effect of sulfonylurea on glucagon secretion is directly on the pancreatic A cell, we examined changes produced by gliclazide in glucagon (IRG), insulin (IRI) and somatostatin (IRS) release from the isolated perfused rat pancreas. Under 5 mM glucose infusion, IRI and IRS were increased by gliclazide in a dose-dependent manner, but IRG was unchanged. When 20 mM arginine was infused to stimulate glucagon secretion, both IRI and IRG increased markedly in a biphasic fashion and IRS increased slightly. The administration of gliclazide at the time of second phase response of IRG, IRI and IRS increased further and IRG decreased at every dose used. Insulin administration to the control and streptozotocin-treated rat pancreas did not change arginine-induced IRG secretion. Gliclazide-induced glucagon suppression was also observed in streptozotocin-diabetic rat pancreas. The amount of administered somatostatin required for inhibiting glucagon secretion was higher than the maximal level obtained from endogenous secretion of somatostatin after gliclazide. Neither cysteamine treatment alone (somatostatin-depleted) nor combined with streptozotocin-treatment (combined depletion of somatostatin and insulin) changed gliclazide-induced glucagon suppression. Thus, it is concluded that suppression of glucagon is induced by sulfonylurea itself.