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991.
Nephropathia epidemica (NE), Puumala (PUU) virus infection, is a febrile disease which is commonly associated with acute renal impairment. To differentiate NE from other acute febrile illnesses, a rapid and reliable serological diagnosis is important, and a number of different protocols have recently been introduced. In the present report we describe a comparative evaluation of six PUU virus immunoglobulin M (IgM) and seven IgG enzyme-linked immunosorbent assay (ELISA) protocols based on native, Escherichia coli-expressed, or baculovirus-expressed nucleocapsid protein (N). Neutralization and immunofluorescence assays were included for comparison. Equally high sensitivities and specificities were obtained with three mu-capture-based IgM ELISAs using native, baculovirus-expressed, and E. coli-expressed N antigens, respectively, and by an ELISA based on purified E. coli-expressed full-length N adsorbed to solid phase. The assays based on truncated amino-terminal N proteins, including a commercially available PUU virus IgM ELISA, all showed lower sensitivities. For detection of PUU virus-specific IgG, ELISAs based on monoclonal antibody-captured native or baculovirus-expressed N antigens showed optimal sensitivities and specificities, while the assays based on E. coli-expressed N did not detect all PUU virus IgG-positive serum samples. A commercially available PUU virus IgG ELISA based on E. coli-expressed amino-terminal N showed a significantly lower sensitivity than those of all other IgG assays.  相似文献   
992.
BACKGROUND: The aim of the present study was to investigate the existence of differences in dental status and in quantitative and qualitative salivary values between 100 patients with liver cirrhosis (LC) and a group of controls. MATERIAL AND METHODS: We analyzed the number of carious, missing and filled teeth. Also the unstimulated (UWS) and stimulated whole saliva flow rates (SWS) were determined, along with the stimulated parotid saliva flow rate (PSS) and the concentration in both UWS and SWS of sodium, potassium, total proteins and immunoglobulin A (IgA). RESULTS: A significantly higher number of carious and missing teeth was observed in the patients with cirrhosis (2.4 and 14.6, respectively) than in the control group (1.3 and 10.6, respectively), and a higher stimulated parotid flow rate with LC (0.64 and 0.44, respectively; p < 0.02) with a decrease in sodium and an increase in potassium, total proteins and IgA in patients with cirrhosis. In the LC group, caries were found to affect more teeth in those patients with alcohol-induced LC than in those with liver disease of other causes (3.9 and 1.7, respectively; p < 0.05), but in contrast, no differences were found in the saliva flow rate and the concentration in both UWS and SWS of sodium, potassium, total proteins and IgA. Finally, no relationship was observed between the dental status and functional hepatic tests. CONCLUSIONS: CH patients showed a worse dental status, a higher SPS rate and some electrolytes and proteins alterations.  相似文献   
993.
OBJECTIVE: To examine the effects of the immunosuppressant, mycophenolate mofetil (MM), on autoimmunity, glomerulonephritis, and mortality in the female NZB x NZW F1 (B/W) mouse model of systemic lupus erythematosus (SLE). METHODS: The development of murine lupus was assessed during the lifespan of 10 female B/W mice given 200 mg/kg/day of MM compared to 10 female B/W mice given vehicle. At 6 week intervals, mice were examined for weight change, albuminuria, antibodies to DNA, and IgG immunoglobulin levels. Morbidity and mortality were assessed daily. In a parallel study, MM treated and control B/W mice were examined at 18 weeks of age for splenocyte phenotype and adhesion molecule expression, as well as antibody titers and in vitro cytokine production in response to immunization with dinitrophenyl-keyhole limpet hemocyanin (DNP-KLH). RESULTS: The administration of MM was well tolerated without apparent side effects. Weight gain in MM treated and control mice was identical through 36 weeks of age. In the treatment group, MM suppressed the development of albuminuria and anti-DNA antibodies compared to the control animals. There were no significant differences between groups in serum concentrations of total IgG. At 60 weeks of age survival in the MM treated group was 100% compared to 10% in the control group. MM did not alter the percentages of CD4, CD8, or IgM positive splenocytes; however, the percentage of CD4+ T lymphocytes expressing very late antigen 4 and intercellular adhesion molecule 1 was reduced. MM inhibited the antibody response to DNP-KLH immunization in vivo; however, in vitro cytokine production in response to KLH was not suppressed. CONCLUSION: MM suppressed the development of autoimmunity and prolonged lifespan in the female B/W mouse model of SLE. Suppression of autoimmunity was achieved without obvious side effects or altered CD4:CD8 T cell ratios. MM may be a useful primary or adjunctive therapy in human SLE.  相似文献   
994.
Splenopentin (SP-5, Arg-Lys-Glu-Val-Tyr) and thymopentin (TP-5, Arg-Lys-Asp-Val-Tyr) are synthetic immunomodulating peptides corresponding to the region 32-34 of a splenic product called splenin (SP) and the thymic hormone thymopoietin (TP), respectively. TP was originally isolated as a 5-kDa (49-amino acids) protein from bovine thymus while studying effects of the thymic extracts on neuromuscular transmission and was subsequently observed to affect T cell differentiation and function. TP I and II are two closely related polypeptides isolated from bovine thymus. A radioimmunoassay for TP revealed a crossreaction with a product found in spleen and lymph node. This product, named splenin, differs from TP only in position 34, aspartic acid for bovine TP and glutamic acid for bovine splenin and it was called TP III as well. Synthetic pentapeptides (TP-5) and (SP-5), reproduce the biological activities of TP and SP, respectively. It is now evident that various forms of TPs were created by proteolytic cleavage of larger proteins during isolation. cDNA clones have been isolated for three alternatively spliced mRNAs that encodes three distinct human T cell TPs. The immunomodulatory properties of TP, SP, TP-5, SP-5 and some of their synthetic analogs reported in the literature have been briefly reviewed.  相似文献   
995.
Germ line transformation of white- Drosophila embryos with P-element vectors containing white expression cassettes results in flies with different eye color phenotypes due to position effects at the sites of transgene insertion. These position effects can be cured by specific DNA elements, such as the Drosophila scs and scs' elements, that have insulator activity in vivo. We have used this system to determine whether human matrix attachment regions (MARs) can function as insulator elements in vivo. Two different human MARs, from the apolipoprotein B and alpha1-antitrypsin loci, insulated white transgene expression from position effects in Drosophila melanogaster. Both elements reduced variability in transgene expression without enhancing levels of white gene expression. In contrast, expression of white transgenes containing human DNA segments without matrix-binding activity was highly variable in Drosophila transformants. These data indicate that human MARs can function as insulator elements in vivo.  相似文献   
996.
We performed a quantitative investigation of arginine-vasopressin (AVP) immunopositive neurons in the suprachiasmatic nucleus (SCN), which is the endogenous clock of the brain of a patient with multiple system atrophy (MSA) who exhibited nocturnal polyuria associated with decreased urinary specific gravity and depression of nocturnal AVP secretion. Eleven age- and sex-matched subjects were used as controls. Although, the number of AVP-positive neurons was decreased in neither the supraoptic nucleus nor the paraventricular nucleus, the number of AVP-positive neurons in the SCN was decreased and gliosis was present in the SCN. The cytoplasmic area of AVP-immunopositive neurons in the SCN was smaller in the patient than in the control subjects. These findings raise the possibility that SCN is involved in MSA and the neurodegeneration in the SCN results in altered circadian rhythm of AVP secretion and nocturnal polyuria.  相似文献   
997.
STUDY DESIGN: Eighteen-month, randomized controlled trial with partial crossover. OBJECTIVES: To test the hypothesis that the control of lumbar flexion in the early morning will significantly reduce chronic, nonspecific low back pain. SUMMARY OF BACKGROUND DATA: Previous studies have indicated an increased risk of low back pain with bending forward in the early morning, primarily because of increased fluid content in the intervertebral discs at that time. METHODS: After 6 months of recording baseline data, 85 subjects with persistent or recurring low back pain were randomly assigned to treatment and control groups. The treatment group received instruction in the control of early morning lumbar flexion. The control group received a sham treatment of six exercises shown to be ineffective in reducing low back pain. Six months later, the control group received the experimental treatment, Diaries were used to record daily levels of pain intensity, disability, impairment, and medication usage. RESULTS: Significant reductions in pain intensity (P < 0.01) were recorded for the treatment group, but not for the control group (point estimate, 33%; 95% confidence interval, 11-55%). After receiving the experimental treatment, the control group responded with similar reductions (P < 0.05). Significant reductions also were observed in total days in pain, disability, impairment, and medication usage. CONCLUSIONS: Controlling lumbar flexion in the early morning is a form of self-care with potential for reducing pain and costs associated with chronic, nonspecific low back pain.  相似文献   
998.
Prepaid or prospective reimbursement has implications for the consultation-liaison (C-L) psychiatrist. The author reviews results from three health policy studies that indicated 1) degree of reliance on general medical providers for mental health care is not affected by generosity of fee-for-service (FFS) coverage, but is greater in some prepaid health care systems; 2) psychological sickness of depressed outpatients visiting general medical providers is similar across prepaid and FFS systems of care; 3) prepaid care is associated with lower rates of detection of depression and counseling in the general medical sector; 4) depression outcomes in the general medical sector are similar under prepaid or FFS care; 5) quality of care for depressed patients is moderate to low in the general medical sector; and 6) depressed elderly inpatients receive higher quality of psychological care in psychiatric units, but they receive higher quality of physical care in general medical wards. The discussion emphasizes the C-L psychiatrist's role in educating general medical providers, improving outcomes for the sickest patients, and improving psychosocial care in prepaid practices.  相似文献   
999.
1000.
Treatment of cultured bovine adrenal chromaffin cells with dbcAMP increased [3H]STX binding with an EC50 of 126 microM and a half-effective time of 12 h; dbcAMP (1 mM x 18 h) raised the Bmax approximately 1.5-fold without altering the Kd value. Forskolin (0.1 mM) or IBMX (0.3 mM) also increased [3H]STX binding, while dbcGMP had no effect. Effects of dbcAMP and forskolin were abolished by H-89, an inhibitor of cAMP-dependent protein kinase. Cycloheximide (10 microgram/ml) and actinomycin D (10 microgram/ml), inhibitors of protein synthesis, nullified the stimulatory effect of dbcAMP, whereas tunicamycin, an inhibitor of protein glycosylation, had no effect. Treatment with dbcAMP augmented veratridine-induced 22Na influx, 45Ca influx via voltage-dependent Ca channels and catecholamine secretion, while the same treatment did not alter 45Ca influx and catecholamine secretion caused by high K (a direct activation of voltage-dependent Ca channels) [25]. Na influx via single Na channel calculated from 22Na influx and [3H]STX binding was quantitatively similar between non-treated and dbcAMP-treated cells. Brevetoxin allosterically enhanced veratridine-induced 22Na influx approximately 3-fold in dbcAMP-treated cells as in non-treated cells. These results suggest that cAMP-dependent protein kinase is involved in the modulation of Na channel expression in adrenal medulla.  相似文献   
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