Structural and functional significance of cysteine residues of glutathione-independent prostaglandin D synthase. Identification of Cys65 as an essential thiol

Glutathione-independent prostaglandin D synthase in rat brain is composed of 189 amino acid residues and catalyzes the isomerization of prostaglandin H2 to prostaglandin D2, an endogenous sleep-promoting substance. This enzyme is the only enzyme among members of the lipocalin superfamily composed of various secretory lipophilic ligand-carrier proteins and is recently identified to be a beta-trace protein, a major constituent of human cerebrospinal fluid. We expressed the active enzyme in Escherichia coli and then systematically substituted all cysteine residues of the delta 1-29 enzyme at positions of 65, 89, and 186 with alanine or serine. The parent and mutant enzymes were purified to apparent homogeneity with a recovery of approximately 30% by chromatography with Sephadex G-50 and S-Sepharose, by which all the enzymes showed identical elution profiles. The purified enzymes, irrespective of the mutation, showed almost the same circular dichroism spectral characteristics as displayed by a highly ordered beta-structure. The recombinant enzymes containing Cys65 showed the activity comparable with that of the enzyme purified from rat brain (approximately 3 mumol/min/mg of protein) in the presence, but not in the absence, of sulfhydryl compounds. However, all of the single, double, and triple mutants without Cys65 lost the enzyme activity. The purified delta 1-29 Ala89,186 enzyme was inactivated reversibly by conjugation with glutathione at Cys65 and irreversibly by the stoichiometric chemical modification with N-ethylmaleimide. These results indicate that Cys65 is an essential thiol of the enzyme and that both the intrinsic and extrinsic sulfhydryl groups are necessary for nonoxidative rearrangement of 9,11-endoperoxide of prostaglandin H2 to produce prostaglandin D2 catalyzed by the enzyme.

Transcutaneous blood glucose monitoring system based on an ISFET glucose sensor and studies on diabetic patients

A transcutaneous blood glucose monitoring system consists of an ion-sensitive field-effect transistor (ISFET) glucose sensor unit and a suction effusion fluid (SEF) collecting unit. The SEF is directly collected by a weak suction (400 mmHg absolute pressure) through the skin from which the corneum layer of the epidermis has been previously removed. An ISFET glucose sensor unit is able to measure glucose concentrations in a microliter order sampling volume. The system was applied to three diabetic patients during a 75 g oral glucose tolerance test for monitoring blood glucose levels. During the experiments, glucose changes in the SEF followed actual blood glucose levels with 10 min delays. Results suggest the feasibility of utilizing quasi-continuous, transcutaneous blood glucose monitoring for individual patients with various diabetic histories or diabetic complications.

Portal and peripheral endotoxins in patients with esophageal varices undergoing surgery

Under the hypothesis that portal endotoxemia, which has been considered evidence of endogenous endotoxemia, is actually a false-positive reaction of the Limulus test, the conventional method of determination, Toxicolor (TOX) and a new endotoxin-specific method, Endospecy (ES) were investigated, whereby portal endotoxemia was reexamined. Peripheral and portal blood samples were collected from 12 patients at various intervals during surgery for esophageal varices, and then evaluated by TOX and ES, the normal values of which are under 60.0 pg/ml and under 9.8 pg/ml, respectively. The mean peripheral and portal endotoxin (Et) levels by TOX were 23.1 pg/ml and 38.9 pg/ml, 1.5 h after the start of surgery, which continued to increase thereafter, the corresponding levels being 48.1 pg/ml and 58.7 pg/ml 8 h after the start of surgery, respectively. The portal Et levels were significantly higher by ES, indicating portal endotoxemia, the mean peripheral and portal Et levels being 6.9 pg/ml, and 6.5 pg/ml, 1.5 h after the start of surgery, these levels showing changes within a similar range. The levels determined by the conventional TOX method increased with time, to a portal Et level of 5.0 pg/ml 8 h after the start of surgery, whereas those determined by ES changed within the same range suggesting that the onset of portal endotoxemia primarily involves the G-factors and that endogenous endotoxemia does not occur.

Characteristics of the chemical forms of 11C, 13N, and 15O induced in air by the operation of a 100 MeV electron linear accelerator

To characterize airborne radioactivity induced by the operation of high-energy accelerators, the fractions of aerosol and gaseous components, and the chemical forms of 11C, 13N, and 15O produced in the air of a target room of a 100 MeV electron linear accelerator were studied. Measurements of radioactivity using a particulate air sampling filter and a gas flow-through ionization chamber showed that more than 98% of 11C, 13N, and 15O were present as gaseous forms. Their chemical forms, detected by means of radio-gas chromatography, were 11C as CO2; 13N as N2 and NO; and 15O as O2 and NO. Machine operating conditions, which affect the compositions of the induced radionuclides and of their chemical forms, and the resulting effect on the estimation of internal doses are discussed.

Immunofluorescence study of immune complexes in polymyalgia rheumatica

Two elderly patients with polymyalgia rheumatica (PMR), one with and the other without temporal arteritis (TA), are presented. Immunofluorescence study of muscle biopsy specimens showed IgG, IgA, and fibrinogen deposits in the perifascicular area in the perimysium. This finding suggests that immune complexes play a role in the pathogenesis of this condition and that the pathophysiology of PMR involves an interstitial inflammatory process.

An isolated left ventricular lesion associated with left ventricular tachycardia--arrhythmogenic "left" ventricular dysplasia?

We present a patient who had a localized myocardial lesion of the left ventricle. Major clinical sequelae were left ventricular tachycardia and heart failure. This case appears to represent a left-sided counterpart of arrhythmogenic right ventricular dysplasia.

Increased serum angiotensin I-converting enzyme activity in patients with mixed connective tissue disease and pulmonary hypertension

The relationship between serum angiotensin I-converting enzyme (ACE) activity, a possible marker of pulmonary endothelial injury, and the occurrence of pulmonary hypertension (PH) in patients with mixed connective tissue disease (MCTD) was investigated. Before corticsteroid therapy, the mean serum ACE level was 26.4 +/- 14.0 mU/ml in patients with MCTD and PH (n = 6), 16.8 +/- 4.1 mU/ml in patients with MCTD but without PH (n = 18), 16.8 +/- 4.1 mU/ml in patients with undifferentiated connective tissue disease (n = 14), and 16.5 +/- 3.9 mU/ml in controls (n = 18). No significant difference in the enzyme activity was found among the groups. However, 4 patients with MCTD showed increased ACE levels (> 28.3 mU/ml), and all of them had PH. Our results suggest that elevation of serum ACE activity may be related to the occurrence of PH in patients with MCTD.

Mitochondrial diabetes mellitus--glucose-induced signaling defects and beta-cell loss

Japanese diabetic patients whose mothers were also diabetic were screened, using peripheral leukocytes, for an A to G transition at nucleotide pair 3243 of the mitochondrial gene, a tRNA(Leu)(UUR) mutation. This mutation was identified in four pedigrees from among 300 unrelated patients. Diabetes mellitus cosegretated with the mutation, except in 1 young subject, and was maternally inherited. Long-term follow-up revealed that the underlying disorder in affected members is a progressive impairment of insulin secretion. In accord with this finding, this mutation was found to be highly prevalent in a subset of diabetes mellitus called slowly progressive IDDM; the mutation was identified in 3 of 27 Japanese patients enrolled in the prospective study of islet cell antibody (ICA)-positive, initially non-insulin-dependent diabetic patients, who are very likely to become insulin dependent in several years. The histologic characteristics of slowly progressive IDDM include loss, though incomplete, of pancreatic beta-cells. Mitochondrial gene defects in beta-cells could therefore cause glucose-induced signaling defects as well as beta-cell loss, which explains the wide range of diabetic phenotypes, from NIDDM phenotype to IDDM, in patients with this mitochondrial gene mutation.

Hyperglycemia as a major determinant of distal polyneuropathy independent of age and diabetes duration in patients with recently diagnosed diabetes

In an attempt to identify the potential risk factors for diabetic neuropathy in patients recently diagnosed as diabetics, 742 non-insulin-dependent diabetics under 70 years of age who had been diagnosed as diabetics less than 5 years before the initial visit were examined in a cross-sectional study conducted at a university hospital. Neuropathy was defined as the presence of symptoms consistent with distal polyneuropathy, or the absence of tendon reflexes. Of the patients, 21% displayed neuropathy in this study, with no differences between the genders. Age was higher, duration of diabetes was longer, body mass index was lower, and fasting plasma glucose level was higher in patients with neuropathy than in those without neuropathy, for both genders. Body height, maximal body mass index, ethanol use, smoking status, systolic and diastolic blood pressure and serum cholesterol level did not differ between the two groups. Logistic regression analysis showed that fasting plasma glucose level (chi 2 = 28.2) was a major determinant for neuropathy independent of diabetes duration (9.5), age (6.2) and maximal body mass index (3.9). Tight glycemic control from the onset of diabetes was concluded to be essential for the prevention of diabetic distal polyneuropathy.

Clostridial gas gangrene associated with congenital generalized lipodystrophy: report of a case

Congenital generalized lipodystrophy (CGL) is a rare disease, the main symptoms of which are a reduction of systemic subcutaneous fat, characteristic facial features, hypertrichosis, and insulin-resistant diabetes. We report herein the unusual case of a 25-year-old man with CGL in whom gas gangrene developed, an association which has never before been encountered.

In situ demonstration of the HTLV-I genome in the spinal cord of a patient with HTLV-I-associated myelopathy

Using polymerase chain reaction (PCR) and in situ hybridization, we investigated the HTLV-I genome in the CNS of an HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patient with a 20-year disease duration. Neuropathologically, there was severe white matter degeneration throughout the spinal cord, but lymphocytic infiltrates were not evident in any lesion. PCR amplification of the pX region of HTLV-I DNA detected its sequence in the spinal cord and all extra-CNS tissue samples. In situ hybridization using probes complementary to the pX and gag regions detected the HTLV-I genome in the cytoplasm and nucleus of cells in the thoracic cord. The findings indicate a direct involvement of HTLV-I in the neurodegeneration of HAM/TSP.

Angiocentric lymphoma with granulomatous panniculitis in the skin expressing natural killer cell and large granular T-cell phenotypes

We investigated three patients suffering from angiocentric lymphoma with granulomatous panniculitis in the skin. All three patients presented with multiple purple subcutaneous nodules. Immunohistologically, the lymphoma cells in all three patients expressed CD2 (T-11), CD56 (neural cell adhesion molecule), and Mik-beta 1 (interleukin-2 beta receptor). CD3s (CD3, Leu-4)-positive lymphoma cells were found in two patients. A pore-forming protein (perforin) was detected in the lymphoma cells of all three patients. Perforin-possessing lymphoid cells were focally scattered in 2 of 15 patients with CD56-negative cutaneous lymphomas who served as controls. By the Southern blot method, one patient showed a rearranged T-cell receptor (TcR)beta gene in the biopsied specimen, and the other two patients had germ-line configurations of TcRs and immunoglobulin heavy chain genes. One patient had serum anti-human T-cell lymphotropic virus (HTLV)-I antibody, but showed no integration of its proviral DNA. Ultrastructurally, membrane-bound azurophilic granules were detected in the atypical lymphoid cells of all three patients. Angiocentric lymphoma with panniculitis in three patients showed the characteristics of natural killer and large granular T-cells. The histological features might be due to the characteristics of the neoplastic cells with azurophilic granules and perforin.

Heterogeneity of Epstein-Barr virus infection in angioimmunoblastic lymphadenopathy type T-cell lymphoma

To investigate the relationship of Epstein-Barr virus (EBV) and angioimmunoblastic lymphadenopathy with dysproteinemia, we performed DNA analysis using the polymerase chain reaction (PCR), Southern blot, in situ hybridization, and immunohistochemical analysis of lymph nodes in five patients who were followed up and biopsied more than once. In the course of the disease, nodal architecture diminished, cellular atypia worsened, and clear cells increased in number. In the DNA analysis of the receptor genes, the clonal population increased in number. EBV nucleic acid sequences were found by either PCR or in situ hybridization in all examined nodes. The number of EBV-positive cells varied widely among the cases and throughout the course of the disease in the same patients. The analysis of EBV terminal repeats or lymphocyte-determined membrane antigen genes showed polyclonal populations of EB-infected cells. EBV-positive cells possessed intermediate- to large-sized nuclei, and the cells with large nuclei, especially, expressed latent membrane protein of EBV. These large cells varied among the cases. Double-labelling immunohistochemistry/in situ hybridization studies demonstrated that most of the EBV-positive cells expressed B-cell antigen (CD20). The presence of EBV seems to be associated with the selective defects of the immune system, rather than with the direct pathogenesis of angioimmunoblastic lymphadenopathy.

Tumor induction in mice administered neonatally with bis(2-oxopropyl)nitrosamine

ICR mice were given four subcutaneous injections of bis(2-oxopropyl)nitrosamine (BOP) 10, 20 and 40 mg/kg body weight, respectively, on day 1, 8, 15 and 22 of age. Animals treated with BOP developed mainly tumors of the lung, liver, nasal cavity, and pancreas. Lung tumors were histologically alveolar cell adenoma or adenocarcinoma at an incidence of 41-100%, hepatocellular adenoma or carcinoma 59-96%, adenoma or adenocarcinoma of the nasal cavity 11-26%, and pancreatic acinar cell adenoma or anaplastic carcinoma 3-7%. No sex difference in response to BOP carcinogen was observed.

Clonal analysis of Hodgkin's disease shows absence of TCR/Ig gene rearrangement, compared with T-cell-rich B-cell lymphoma and incipient adult T-cell leukemia/lymphoma

To better characterize the clonality and pathogenesis of Hodgkin's disease (HD), we used polymerase chain reaction (PCR) and Southern blot to analyze the rearrangement of immunoglobulin (Ig) and T-cell receptor (TCR) genes, the bcl-2 oncogene, and the Epstein-Barr virus (EBV) genotype. In situ hybridization studies of EBV were also done. Twenty-six cases of HD were compared with 15 cases of non-specific lymphadenitis, 7 with incipient adult T-cell leukemia/lymphoma (ATLL), and 4 T-cell rich B-cell lymphomas (TRBL), all of which histologically resembled HD. EBV genes were detected in 20 of 26 HD patients (77%) and in 7 of 15 patients with non-specific lymphadenitis (47%), 5 of 7 with incipient ATLL (71%), and 1 of 4 with TRBL (25%). In contrast to specimens of non-specific lymphadenitis, TRBL, and incipient ATLL, only one EBV genotype was evident in the specimens of HD. EBV latent membrane protein (LMP) was detected immunologically in 16 of 26 HD patients (62%), one of four TRBL (25%) and one of seven incipient ATLL (14%), but it was not evident in non-specific lymphadenitis. The LMP positive cases showed amplified EBV genomes. Only one of the 26 cases of HD had a bcl-2 gene rearrangement by PCR, but this was not seen in any other disease. The bcl-2 protein was detected immunologically in seven of the 26 HD patients (27%) and in one of the seven incipient ATLL cases (14%). EBV has been reported to upregulate bcl-2 expression, but in this study the presence of bcl-2 protein did not correlate with the presence of the t(14;18) translocation or EBV-LMP. All TRBLs showed rearrangement of the immunoglobulin genes by PCR and/or Southern blot, and the giant cells were of B-cell type. All incipient ATLLs displayed rearrangement of the TCR genes, and the giant cells were of T-cell origin. In seven of 26 HD cases, the giant cells were weakly stained with T-cell antibodies, in another seven positive with B-cell antibodies and in 18 instances polyclonally positive for both kappa and lambda. However, PCR and Southern blot displayed only two cases of TCR gene rearrangement, while two others had very weak rearrangements of immunoglobulin gene positive only by PCR. Thus the T and B-cell genotype did not correlate with the T and B-cell phenotype recorded in these cases. The absence of Ig and TCR gene rearrangements seems to be common in HD, compared with in TRBL and incipient ATLL.

Budd-Chiari syndrome and Epstein-Barr virus (EBV) associated plasmacytoma in a patient with chronic active EBV infection

A 42-year-old Japanese man with chronic active Epstein-Barr virus (EBV) infection initially responded to treatment with interleukin-2 (IL-2). Six months later he developed thrombosis in the hepatic veins, and Budd-Chiari syndrome associated with severe hepatic damage was diagnosed. He also developed a solitary EBV-positive plasmacytoma in the right femur. Since these rare complications occurred after long-term IL-2 therapy, the possibility that long-term IL-2 therapy might cause Budd-Chiari syndrome and liver damage as well as EBV-associated plasmacytoma is discussed.

[Anemia and neutropenia in elderly patients caused by copper deficiency for long-term enteral nutrition]

Anemia and neutropenia caused by copper deficiency is a well-known consequence of long term total parenteral nutrition in the literature. We present 6 bed-ridden elderly patients who developed anemia and neutropenia after receiving enteral nutrition for a long time (mean: 3.3 years) In all 6 patients, serum copper and ceruloplasmin level were very low, and the mean of their hematological data were as follows: WBC 2,200/microliters, neutrophil 554/microliters, hemoglobin 8.1 g/dl, platelet 260 x 10(3)/microliters, respectively. The bone marrow examination showed cytoplasmic vacuolization of both myeloid and erythroid precursors, and maturation arrest of granulopoiesis. Then, copper sulfate was administrated by enteral tube to 6 patients, and the improvement of anemia and neutropenia was observed within a month. A 82-year-old woman who received enteral nutrition for 3.5 years with sever anemia (Hb 3.7 g/dl) and neutropenia (neutrophil 350/microliters), showed a marked improvement in hematological data (Hb 8.0 g/dl, neutrophil 4, 092/microliters, respectively) after two months by administering the copper supplementation. The exact cause of the anemia and neutropenia in copper deficiency is unclear, but it is suggested that the decreased activity of enzyme containing copper may be related. Hematological abnormalities due to copper deficiency should be cared during long term enteral nutrition with long termed bed-ridden elderly patients.

Inhibitory effect of 4-acylaminophenol derivatives (T-0799 and T-0757), novel lipoxygenase inhibitors, on arachidonic acid-induced infiltration of polymorphonuclear leukocytes in rat skin

Effects of 4-acylaminophenol derivatives, novel 5-lipoxygenase inhibitors, on the neutrophil infiltration in arachidonic acid (AA) (10 mg/site)-induced skin inflammation in rats were examined. Myeloperoxidase (MPO) activity in the skin lesion, used as an indicator of neutrophil infiltration, was significantly increased after intradermal injection of AA. Dual inhibitors of cyclooxygenase and 5-lipoxygenase, phenidone (100 mg/kg x 2, i.p. and p.o.) and BW-755C (50 mg/kg x 2, p.o.), and 5-lipoxygenase inhibitors, AA-861 (100 mg/kg x 2, i.p.) and the 4-acylaminophenol derivatives T-0799 and T-0757 (10-100 mg/kg x 2, p.o.), inhibited the increase in MPO activity 5 hr after AA-injection, but the cyclooxygenase inhibitor indomethacin (5 mg/kg, i.p.) showed no effect. These results suggest that products of lipoxygenase, but not of cyclooxygenase, are involved in the MPO activity increase (i.e., neutrophil infiltration), and that this model is useful for in vivo evaluation of 5-lipoxygenase inhibitors. It is suggested that the 4-acylaminophenol derivatives may be useful as orally active drugs for treatment of some leukotriene-mediated diseases.

[Estimation of neural generators of cognitive potential P300 by dipole tracing method]

A computer-aided method dipole tracing system, allows to estimate the location of the generator of brain potentials and has the advantage of non-invasive recording in physiological state. In this experiment, a two-dipole model and a four-dipole model of the active electrical sources of the cognitive component P300 of event related potentials have been examined by using dipole tracing method in normal human subjects. We have recorded P300 in a group of 3 healthy females aged 19-24 years, using somatosensory stimuli requiring a button-press response. The brain potentials were recorded with 21 surface electrodes placed over the scalp. Three-dimensional coordinates of surface electrodes and scalp, skull and brain (SSB) geometry of the subjects were measured by special device and three-dimensional MRI images, respectively. In order to estimate the localization of active dipoles, the conductivities of the scalp, the skull and the brain were approximated to be 1: 1/80: 1. In the present study, with data derived from all 21 channels, the sources of individual P300 components were analyzed during 10-30 msec at every 1 msec intervals. As a result, the dipole locations for each subjects were similar both in the two dipole model and in the four dipole model. The calculation on two dipole model showed the generators of P300 situated symmetrically in the frontal lobe. Whereas, the calculation on four dipole model showed them situated symmetrically near the hippocampus and in the parietal cortex which were close to the neural generators of P300 reported by other authors.(ABSTRACT TRUNCATED AT 250 WORDS)