Biomedical subjects

A Ueda

Publications and source records attributed to A Ueda.

At least 55 records · Page 3Linked to original sources

PubMed2000

Human T-cell leukemia virus type I tax activates transcription of the human monocyte chemoattractant protein-1 gene through two nuclear factor-kappaB sites.

Infection by human T-cell leukemia virus type (HTLV) I leads to adult T-cell leukemia and is also associated with the neurodegenerative disease HTLV-I-associated myelopathy/tropical spastic paraparesis. Leukocytes are attracted to sites of inflammation by chemokines. One such chemokine is monocyte chemoattractant protein (MCP)-1, a member of the C-C subfamily of chemokines. We investigated whether HTLV-I infection causes up-regulation of MCP-1, which may in turn cause recruitment of leukocytes to HTLV-I-infected areas. We now report that MCP-1 mRNA levels are elevated in HTLV-I-infected T-cell lines, when compared with uninfected ones. We further confirmed secretion of MCP-1 by HTLV-I-infected T-cell lines. MCP-1 mRNA was also expressed in leukemic cells from patients with adult T-cell leukemia. The 5' transcriptional regulatory region of the MCP-1 gene was activated by the HTLV-I-encoded transactivator Tax in the human T-cell line Jurkat, in which endogenous MCP-1 is induced by Tax. By using site-specific point mutations, we have identified two closely spaced nuclear factor (NF)-kappaB sites, A1 and A2, to be important for Tax-mediated transactivation of the MCP-1 gene. Through the use of an electrophoretic mobility shift assay, we demonstrated that Tax induced NF-kappaB binding to both MCP-1 kappaB sites. This is the first report to demonstrate that Tax can transactivate the MCP-1 gene through the induction of NF-kappaB. Our results thus reveal how Tax disrupts the normally regulated MCP-1 gene and leads to its constitutive expression in HTLV-I-infected cells. These findings may have important implications for our understanding of HTLV-I-associated diseases.

Binding Sites↗

PubMed2000

Human umbilical vein endothelial cells (HUVECs) show Ca(2+) mobilization as well as Ca(2+) influx upon hypoxia.

Bleb formation is an early event of cellular damage observed in a variety of cell types upon hypoxia. Although we previously found that the [Ca(2+)](i) rise before bleb formation only at the same loci of HUVECs upon hypoxia (localized [Ca(2+)](i) rise), the mode of the [Ca(2+)](i) rise remains ill-defined. In order to clarify the mechanisms causing the localized [Ca(2+)](i) rise in hypoxia challenged HUVECs, we studied the effects of several Ca(2+) channel blockers or a Ca(2+) chelator, EGTA, which reduces extracellular Ca(2+) concentration on the hypoxia-induced localized [Ca(2+)](i) rise and bleb formation by employing a confocal laser scanning microscopy (CLSM). After the initiation of hypoxia, [Ca(2+)](i) rose gradually in a localized fashion up to 15 min, which was associated with bleb formation at the same loci. The maximal [Ca(2+)](i) rise was 435 +/- 84 nM at the loci of bleb formation. Ca(2+) channel blockers including Ni(2+) (non-specific, 1 mM), nifedipine (L type, 10 microM), nicardipine (L + T type, 10 microM), and cilnidipine (L + N type, 10 microM) did not inhibit either the localized [Ca(2+)](i) rise or bleb formation. Although both the localized [Ca(2+)](i) rise and bleb formation were inhibited by lowering extracellular Ca(2+) concentration below 100 nM, a diffuse [Ca(2+)](i) rise through the cytoplasm remained without bleb formation, which was inhibited by a phospholipase C (PLC) inhibitor, U73122. In conclusion, hypoxia causes both the Ca(2+) mobilization and the Ca(2+) influx in HUVECs and the Ca(2+) influx through unknown Ca(2+) channels is responsible for the localized [Ca(2+)](i) rise integral to bleb formation.

Calcium↗

PubMed2000

Role of cAMP cascade in synaptic stability and plasticity: ultrastructural and physiological analyses of individual synaptic boutons in Drosophila memory mutants.

Mutations of the genes rutabaga (rut) and dunce (dnc) affect the synthesis and degradation of cAMP, respectively, and disrupt learning in Drosophila. Combined ultrastructural analysis and focal electrophysiological recording in the larval neuromuscular junction revealed a loss of stability and fine tuning of synaptic structure and function in both mutants. Increased ratios of docked/undocked vesicles and poorly defined synaptic specializations characterized dnc synapses. In contrast, rut boutons possessed fewer, although larger, synapses with lower proportions of docked vesicles. At reduced Ca(2+) levels, decreased quantal content coupled with an increase in failure rate was seen in rut boutons and reduced pair-pulse facilitation were found in both rut and dnc mutants. At physiological Ca(2+) levels, strong enhancement, instead of depression, in evoked release was observed in some dnc and rut boutons during 10 Hz tetanus. Furthermore, increased variability of synaptic transmission, including fluctuation and asynchronicity of evoked release, paralleled an increase in synapse size variation in both dnc and rut boutons, which might impose problems for effective signal processing in the nervous system. Pharmacological and genetic studies indicated broader ranges of physiological alteration by dnc and rut mutations than either the acute effects of cAMP analogs or the available mutations that affect cAMP-dependent protein kinase (PKA) activity. This is consistent with previous reports of more severe learning defects in dnc and rut mutations than these PKA mutants and allows identification of the phenotypes involving long-term developmental regulation and those conferred by PKA.

Alleles↗

PubMed2000

Positive and negative regulatory elements contribute to CpG oligonucleotide-mediated regulation of human IL-6 gene expression.

Oligonucleotides (ODN) expressing immunostimulatory "CpG motifs" activate human RPMI 8226 myeloma cells to secrete IL-6. Using deletion and site-directed mutagenesis of the human (h)IL-6 promoter region, two positive regulatory elements (the binding sites for the 5'-CCAAT / enhancer binding protein-beta and NF-kappaB) were identified. Two negative regulatory elements, the 3'-retinoblastoma control element (RCE) and the binding site for Epstein-Barr virus C-promoter binding factor 1 (CBF1), also contributed to CpG ODN induction of hIL-6 gene expression. Of interest, CpG ODN treatment induced the dissociation of a repressor protein from its 3'-RCE binding site. Thus, CpG ODN regulation of hIL-6 gene expression involves both enhancer and derepression mechanisms.

CCAAT-Enhancer-Binding Proteins↗

PubMed2000

IL-12-encoding plasmid has a beneficial effect on spontaneous autoimmune disease in MRL/MP-lpr/lpr mice.

Systemic lupus erythematosus (SLE) is characterized by immune abnormalities explained by the overproduction of Th(2)cytokines such as autoantibody production and polyclonal B cell activation. We examined the effect of administering a DNA plasmid encoding IL-12 on the lupus-like disease of MRL/MP-lpr/lpr (MRL/lpr) mice. Treatments were delivered intramuscularly every 4 weeks, starting at 4 weeks of age. This intervention significantly inhibited the accumulation of CD4(-)CD8(-)T cells, and reduced lymphadenopathy and splenomegaly. A significant decrease in serum IgG anti-DNA autoantibody titers was observed, and plasmid IL-12 therapy was also associated with a reduction in the proteinuria and glomerulonephritis characteristic of this disease. Serum IFN-gamma level was increased by inoculating IL-12 encoding plasmid, suggesting that the cytokine balance was skewed towards Th(1). The clinical implications of this suppression of autoimmune disease are also discussed.

Animals↗

PubMed2000

Fatty acid-specific, regiospecific, and stereospecific hydroxylation by cytochrome P450 (CYP152B1) from Sphingomonas paucimobilis: substrate structure required for alpha-hydroxylation.

Fatty acid alpha-hydroxylase from Sphingomonas paucimobilis is an unusual cytochrome P450 enzyme that hydroxylates the alpha-carbon of fatty acids in the presence of H2O2. Herein, we describe our investigation concerning the utilization of various substrates and the optical configuration of the alpha-hydroxyl product using a recombinant form of this enzyme. This enzyme can metabolize saturated fatty acids with carbon chain lengths of more than 10. The Km value for pentadecanoic acid (C15) was the smallest among the saturated fatty acids tested (C10-C18) and that for myristic acid (C14) showed similar enzyme kinetics to those seen for C15. As shorter or longer carbon chain lengths were used, Km values increased. The turnover numbers for fatty acids with carbon chain lengths of more than 11 were of the same order of magnitude (10(3) min(-1)), but the turnover number for undecanoic acid (C11) was less. Dicarboxylic fatty acids and methyl myristate were not metabolized, but monomethyl hexadecanedioate and omega-hydroxypalmitic acid were metabolized, though with lower turnover values. Arachidonic acid was a good substrate, comparable to C14 or C15. The metabolite of arachidonic acid was only alpha-hydroxyarachidonic acid. Alkanes, fatty alcohols, and fatty aldehydes were not utilized as substrates. Analysis of the optical configurations of the alpha-hydroxylated products demonstrated that the products were S-enantiomers (more than 98% enantiomerically pure). These results suggested that this P450 enzyme is strictly responsible for fatty acids and catalyzes highly stereo- and regioselective hydroxylation, where structure of omega-carbon and carboxyl carbon as well as carbon chain length of fatty acids are important for substrate-enzyme interaction.

Arachidonic Acid↗

PubMed2000

Polyketide synthase gene coupled to the peptide synthetase module involved in the biosynthesis of the cyclic heptapeptide microcystin.

The peptide synthetase gene operon, which consists of mcyA, mcyB, and mcyC, for the activation and incorporation of the five amino acid constituents of microcystin has been identified [T. Nishizawa et al. (1999) J. Biochem. 126, 520-529]. By sequencing an additional 34 kb of DNA from microcystin-producing Microcystis aeruginosa K-139, we identified the residual microcystin synthetase gene operon, which consists of mcyD, mcyE, mcyF, and mcyG, in the opposite orientation to the mcyABC operon. McyD consisted of two polyketide synthase modules, and McyE contained a polyketide synthase module at the N-terminus and a peptide synthetase module at the C-terminus. McyF was found to exhibit similarity to amino acid racemase. McyG consisted of a peptide synthetase module at the N-terminus and a polyketide synthase at the C-terminus. The microcystin synthetase gene cluster was conserved in another microcystin-producing strain, Microcystis sp. S-70, which produces Microcystin-LR, -RR, and -YR. Insertional mutagenesis of mcyA, mcyD, or mcyE in Microcystis sp. S-70 abolished microcystin production. In conclusion, the mcyDEFG operon is presumed to be responsible for 3-amino-9-methoxy-2,6, 8-trimethyl-10-phenyldeca-4,6-dienoic acid (Adda) biosynthesis, and the incorporation of Adda and glutamic acid into the microcystin molecule.

Amino Acid Sequence↗

PubMed2000

Hemodialysis does not influence the peroxidative state already present in uremia.

Hemodialysis (HD) patients are exposed to high oxidative stress, however, the nature of this stress is still unclear. In this study, we employed a specific lipid peroxidative product, phosphatidylcholine hydroperoxide (PCOOH), and evaluated the peroxidative effect of end stage renal disease by measuring thiobarbituric acid reactive substances (TBARS) and PCOOH in both plasma and erythrocyte membrane. We also surveyed plasma TBARS and PCOOH before and after HD sessions thereby assessing oxidative stress by a single HD procedure. The plasma TBARS level of healthy controls was 2.9 +/- 0.4 nmol/ml. Those of HD patients before and after HD session were 5.1 +/- 1.4 and 3.1 +/- 0.5 nmol/ml, respectively, and the pre-HD plasma TBARS levels were significantly higher than those of controls and after HD. The plasma PCOOH concentration of patients before HD was 119.7 +/- 58.4 pmol/ml and was significantly higher than that of controls which was 88.6 +/- 14.3 pmol/ml. After HD, the plasma PCOOH level decreased to 103.2 +/- 36.0 pmol/ml, which was still significantly higher than that of controls. In erythrocytes, the PCOOH level of patients was 259.3 +/- 105.4 nmol/g RBC and was significantly higher than that of controls with 88.6 +/- 32.0 nmol/g RBC. Analyzed with respect to the cause of renal disease, the polycystic kidney disease patients showed significantly lower plasma PCOOH levels than the others. These results suggest that there is an increase of lipid peroxidation in both plasma and erythrocytes of HD patients, though this oxidative stress was not brought about by HD.

Erythrocyte Membrane↗

PubMed2000

[A Japanese language version of the health-promoting lifestyle profile].

The development and initial psychometric evaluation of a Japanese version of the Health-Promoting Lifestyle Profile II (HPLP II) is described. The 52-item instrument was translated into Japanese and was found to be culturally relevant and reliable in a pilot study. The Japanese version was then administered to adiverse but predominantly Japanese group of 337 subjects residing in northern Japan. The Japanese version of the HPLP II was evaluated using factor analysis and reliability measurement. Six factors similar to those isolated previously during psychometric assessment of the English language version were extracted. Those six dimensions comprise the HPLP II subscales of: 1. Health responsibility, 2. Spiritual growth, 3. Physical activity, 4. Interpersonal relations, 5. Nutrition, and 6. Stress management. The alpha reliability coefficient for the total scale was 0.94 and the 2-week retest reliability was 0.91; the alpha coefficients for the subscales ranged from 0.70 to 0.87. The Japanese language version of the HPLP II appears to have sufficient validity and reliability for use by researchers who wish to describe the health-promoting components of lifestyle among the Japanese population and to explore differences and similarities in the health-promoting lifestyle of Japanese and American subjects or those of other ethnic groups. Further evaluations of measurement with different populations appears warranted. This instrument will enable researchers to investigate patterns and determinants of health-promoting lifestyle, as well as the effects of interventions to alter the lifestyle.

Health Promotion↗

PubMed2000

Abnormal Ca2+ handling and increased Mg2+ permeability in platelets of hypertensive rats.

In order to test the hypothesis that intracellular Na+ accumulation and cellular Mg2+ deficiency may be involved in the abnormalities in Ca2+ handling and reactivity in spontaneously hypertensive rats (SHR) platelets, the metabolism of Na+, Ca2+ and Mg2+ was determined in fluorescent dye loaded platelets from 15 SHR and 15 Wistar-Kyoto rats (WKY) at 12 weeks of age. Mg2+ leak was estimated as the Mg2+ influx induced by an increase in extracellular [Mg2+] (from 1 to 5 mmol/l) and Mg2+/Na+ exchange activity was estimated as the Mg2+ influx induced by a decrease in extracellular [Na+] (from 140 to 50 mmol/l). Cellular metabolism of the fluorescent dye was similar in the two groups. Mean platelet [Ca2+]i was significantly increased under basal and thrombin (0.1 U/ml)-stimulated conditions in SHR compared to WKY, both in the presence and absence of extracellular Ca2+. Mean Ca2+ discharge capacity was similar between the two groups. There was no difference in mean [Na+]i between the two groups. Basal [Mg2+]i was also increased in SHR platelets. Mg2+ leak was higher in SHR than in WKY, while Mg2+/Na+ exchange activity was similar in the two groups. There was no difference in serum Mg2+ concentration between SHR and WKY. These data suggest that abnormal Ca2+ handling is accompanied by elevation in [Mg2+]i via increased permeability of platelet cell membranes to Mg2+ in SHR without any alteration in [Na+]i, and do not support the Mg2+ deficiency hypothesis in genetically hypertensive rats.

Animals↗

PubMed2000

[Hematological abnormalities of primary Sjogren's syndrome].

Sjogren's syndrome (SS) is an autoimmune disease characterized by a chronic inflammatory response mainly localized to the lacrimal and salivary glands. However, it sometimes involves extraglandular organs culminating in systemic disorders. Hematological abnormalities are not uncommon, although they rarely have clinical significance. In this study we examined 99 patients with primary SS who visited our hospital during 1989 to 1999. Patient's mean age was 54.1 years and 95 out of 99 were female. Lymphopenia and leukopenia was noted in 35 patients (35.3%) and 26 patients (26.2%) respectively, and 7 patients (7.1%) had thrombocytopenia. 43 patients (43.4%) had either of these hematological abnormalities. Patients with lymphopenia showed significantly low frequency of arthralgia and anti-SS-A/B antibody was more common in this group. Only one patient in this group required prednisolone therapy because of polyarthritis and general fatigue while others needed no specific therapy. Patients with thrombocytopenia were significantly younger and a male/female ratio was higher than those without this abnormality. They had higher tendency to accompany with skin eruption, positive anti-SS-B antibody, anti-nuclear antibody and rheumatoid factor. Three out of 8 patients with thrombocytopenia were treated with prednisolone according to the protocol for idiopathic thrombocytopenic purpura. All of 3 patients had positive PA-IgG and normocellular bone marrow. Autoimmune mechanism such as polyclonal B cell activation may play a role in the pathogenesis of thrombocytopenia.

Female↗

PubMed2000

[Pulmonary hypertension in a patient with primary Sjogren's syndrome, Hashimoto's disease, and primary biliary cirrhosis].

A 53-year-old woman was admitted to our hospital in May 1999, because of progressive dyspnea and liver dysfunction. She had been receiving the replacement therapy of thyroid hormone for thirteen years and suffering from Raynaud's phenomenon for 9 years. She experienced exertional dyspnea and sicca symptom for 3 years, and had an episode of syncope 4 months before admission. An echocardiogram showed dilation of the right ventricle, tricuspid regurgitation and the estimated mean pressure of the pulmonary artery was higher than 120 mmHg. She was diagnosed as having severe pulmonary hypertension (PH) complicated with primary Sjogren's syndrome and primary biliary cirrhosis without portal hypertension She was treated with anticoagulant (warfarin) and oral prostagrandin I2 (prostacyclin). However, right heart failure and jaundice gradually progressed and she suddenly died in December 1999. At autopsy, the heart was enlarged with right ventricular hypertrophy. Small arteries and arterioles in the lung showed concentric intimal proliferation and severe plexogenic vascular disease. Deposition of immunoglobulin was not observed in the pulmonary arteries. Since the prognosis of PH is poor, it is important to analyze the etiology of the disease for the development of the treatment.

Fatal Outcome↗

PubMed2000

Abnormal magnesium status in patients with cardiovascular diseases.

To investigate magnesium status in patients with cardiovascular diseases and in those presenting high factors for these diseases, we measured the concentrations of serum total Mg, serum ionized Mg and intra-erythrocyte Mg. Mg is an important cofactor for many enzymes, especially those involved in phosphate transfer reactions. Mg deficiency has been shown to be associated with fatal cardiovascular diseases, as well as with risk factors for these diseases. Only measurement of the serum concentration of total Mg is routinely available, but ionized Mg is the physiologically active component. Furthermore, most of the body's Mg is present in the intracellular space. Subjects included patients with ischaemic heart disease (n=80), cardiac arrhythmia (n=60), diabetes mellitus (n=36), essential hypertension (n=194) and hypercholesterolaemia (n=60). The same measurements were made in healthy controls (30 men and 26 women; mean age 58+/-11 years). The serum ionized Mg concentration was measured with a selective ion electrode. The intra-erythrocyte Mg concentration was measured by atomic absorption. No gender difference was found for any Mg parameter, nor was age related to any Mg parameter. The serum albumin concentration was positively correlated only with the serum total Mg concentration. Although the serum total Mg concentration was similar in all groups, patients with diabetes mellitus and arrhythmia had lower serum levels of ionized Mg. Patients with essential hypertension exhibited higher intra-erythrocyte Mg concentrations than the healthy controls. Thus the measurement of serum total Mg concentration may obscure the presence of extracellular Mg deficiency in patients with arrhythmia and diabetes mellitus. Furthermore, the intracellular accumulation of Mg does not support the hypothesis of Mg deficiency in patients with essential hypertension.

Biomarkers↗

PubMed2000

Low extracellular Mg2+ concentrations suppress phagocytosis in vitro by alveolar macrophages from rats.

The aim of this study was to assess the effects of extracellular Mg2+ concentrations on phagocytosis in vitro by alveolar macrophages from rats. Phagocytosis was suppressed in the presence of low, but not high, Mg2+ concentrations. Vanadate, a Mg(2+)-ATPase inhibitor, suppressed phagocytosis. In the presence of a low Mg2+ concentration or vanadate, the cytosolic free Ca2+ concentration ([Ca2+]i) increased, but the cytosolic free Mg2+ concentration did not. These results suggest that low extracellular Mg2+ concentrations and vanadate suppress phagocytosis by rat alveolar macrophages by increasing [Ca2+]i.

Animals↗

PubMed2000

[Assessment on intermittent intravenous cyclophosphamide pulse therapy in diffuse proliferative lupus nephritis].

OBJECTIVE: To determine whether intravenous cyclophosphamide pulse therapy (IVCY) is effective for treating patients with diffuse proliferative lupus nephritis (DPLN) who were 1) refractory to methylprednisolone pulse therapy (MP) or 2) could not be treated with MP because of severe diabetes or steroid induced psychosis. METHODS: Seven patients with biopsy proven DPLN were studied after informed consent. Five of them received IVCY after a failure to achieve renal remission with at least 2 cycles of MP therapy. Of the other 2 patients, one had severe diabetes and the other a history of steroid induced psychosis. Bolus therapy with cyclophosphamide (0.5 g/m2 body surface area) was given once a month for 6 consecutive months and then once every 3 months for a total treatment period of 1 year. All patients were given oral prednisone, 0.5 mg/kg per day. The prednisone dose was tapered to the minimal dose required for controlling the disease. After 1 year, the renal status of the patients were evaluated. RESULTS: At 1 year, 4 of the 7 patients achieved substantial improvement. Although the other 3 patients did not satisfy the definition of substantial improvement, none of them had progressive disease. Adverse events were mild and did not require any treatment, with 2 cases of leukocytopenia without fever or major infection. No cases of hemorrhagic cystitis or amenorrhea were observed. CONCLUSIONS: IVCY was 1) effective in the treatment of DPLN which was refractory to MP and 2) relatively safe with minimal side effects.

Adult↗

PubMed2000

[Evaluation of hearing disorders and social support among the middle aged and elderly in the community. I. Analysis on the relationship between hearing difficulties and social participation, and self-rated health].

OBJECTIVES: To clarify the actual conditions of middle-aged and elderly community residents with hearing disabilities; and to investigate, through self-evaluation, the impact of hearing difficulties on health and social participation so that a key can be found to provide social support for residents with some degree of hearing impairment. METHODS: A questionnaire survey was conducted in Soyo village in Kumamoto Prefecture. The subjects of the survey were 2,199 residents aged 40 years and older receiving health check-ups in accordance with the Health Service Act for the Aged. The questionnaires consisted of 8 items regarding self-evaluations of health, hearing difficulties, the utilization of hearing aids, tinnitus, and social life. RESULTS: Data from 2,075 respondents who completed the questionnaire were analyzed. The results were as follows: 1. The number of residents claiming hearing difficulties according to age: 40 s--1 man (0.6%) 50 s--7 men (3.9%) and 7 women (2.8%) 60 s--26 men (8.3%) and 16 women (4.2%) 70 s(+)--42 men (17.5%) and 37 women (11.1%) The percentage of respondents suffering from hearing difficulties increased significantly with age with percentages higher in men than in women among all age groups. 2. Thirty-eight men and 32 women reported customary use of a hearing aid. Hearing aid use was 0.6% among men in their 40 s, 1.1% in men and 1.2% for women in their 50 s, 3.2% in men and 1.6% for women in their 60 s, 10.4% in men and 6.9% in women in their 70 s or older. 3. Logistic regression analysis showed a significant association between hearing difficulties and social participation (Odds ratio: 1.56; 95% Confidence Interval, 1.02-2.38). The degree of social participation (participation in a variety of activities/communication by telephone) was restricted by hearing difficulties. 4. Logistic regression analysis showed a significant association between hearing difficulties and self-evaluated health (Odds ratio: 2.47; 95% Confidence Interval, 1.38-4.42. The elderly with hering difficulties tended to show lower self-evaluated health. CONCLUSIONS: This study suggests the necessity of creating and implementing social policies that deepen residents' awareness of hearing disabilities as invisible barriers in the home, in the workplace, and in the community; and the necessity of improving the living environment through the utilization of barrier-free designs that will foster better communication.

Adult↗

PubMed2000

[Two cases of acute lupus peritonitis].

We report two cases of systemic lupus erythematosus (SLE) diagnosed when acute peritonitis was appeared. Case 1 was a 20 year-old woman suffering from stomachache and right lower abdominal pain. Case 2 was a 40 year-old woman with diarrhea, epigastralgia, pollakisuria. In both cases, their peritoneal fluids were exudative with positive autoantibodies. After high dose steroid therapy, abdominal symptoms and ascites improved promptly. However, due to the complication of lupus nephritis, additional therapy was necessary. To characterize the feature of lupus peritonitis (LP), we examined the clinical and laboratory findings of LP from the literature. In patients with acute LP, abdominal pain, vomiting, diarrhea were significantly more common compared with chronic LP patients (P < 0.05), and fever, arthritis, central nervous system involvement and cystitis were more common. In patients with chronic LP, pleural effusion and pericardial effusion were more common compared with acute LP patients. Gastrointestinal manifestations such as abdominal pain, vomiting and diarrhea were more common in patients with acute LP compared with patients with chronic LP. Most patients with chronic LP were asymptomatic, ascites and serositis being the only clinical findings. The response to steroid therapy was better in acute LP.

Acute Disease↗

PubMed1999

Selective effects of neuronal-synaptobrevin mutations on transmitter release evoked by sustained versus transient Ca2+ increases and by cAMP.

Synaptobrevin is a key constituent of the synaptic vesicle membrane. The neuronal-synaptobrevin (n-syb) gene in Drosophila is essential for nerve-evoked synaptic currents, but miniature excitatory synaptic currents (mESCs) remain even in the complete absence of this gene. To further characterize the defect in these mutants, we have examined conditions that stimulate secretion. Despite the inability of an action potential to trigger fusion, high K+ saline could increase the frequency of mESCs 4- to 17-fold in a Ca2+-dependent manner, and the rate of fusion approached 25% of that seen in wild-type synapses under the same conditions. Similarly, the mESC frequency in n-syb null mutants could be increased by a Ca2+ ionophore, A23187, and by black widow spider venom. Thus, the ability of the vesicles to fuse in response to sustained increases in cytosolic Ca2+ persisted in the absence of this protein. Tetanic stimulation could also increase the frequency of mESCs, particularly toward the end of a train and after the train of stimuli. In contrast, these mutants did not respond to an elevation of cAMP induced by an activator of adenylyl cyclase, forskolin, or a membrane-permeable analog of cAMP, dibutyryl cAMP, which in wild-type synapses causes a marked increase in the mESC frequency even in the absence of external Ca2+. These results are discussed in the context of models that invoke a special role for n-syb in coupling fusion to the transient, local changes in Ca2+ and an as yet unidentified target of cAMP.

Cadmium↗