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31.
DNA microarray analysis reveals novel gene expression profiles in collagen-induced arthritis 总被引:4,自引:0,他引:4
Thornton S Sowders D Aronow B Witte DP Brunner HI Giannini EH Hirsch R 《Clinical immunology (Orlando, Fla.)》2002,105(2):155-168
Global gene expression was analyzed in early and late collagen-induced arthritis (CIA). Of 8734 cDNAs analyzed, 330 were induced and 55 downregulated greater than twofold in early or late disease. Hierarchical clustering of these 385 cDNAs demonstrated five distinct expression patterns differentiating early from late disease and correlating with histopathologic changes in the paw. Of the 385 cDNAs, 185 are known, characterized genes, the majority of which are not described as playing a role in arthritis. However, several of these genes are involved in pathological processes relating to arthritis, including apoptosis, inflammation, and cellular proliferation. One interesting gene, follistatin-like gene, is highly expressed along the margin of contact between inflammatory synovial pannus and eroding bone, suggesting a role in joint destruction. These results demonstrate that global gene expression profiles distinguish early and late CIA and reveal several genes novel to arthritis the further characterization of which will advance our understanding of arthritis. 相似文献
32.
Hirsch VM 《AIDS reviews》2004,6(1):40-53
The simian immunodeficiency viruses are a diverse group of viruses that naturally infect a wide range of African primates, including chimpanzees, African green monkeys (AGM) and sooty mangabey monkeys (SM). Although natural infection is widespread in feral populations of AGMs and SMs, this infection does not result in immunodeficiency. However, experimental inoculation of Asian macaque species results in an immunodeficiency syndrome that is remarkably similar in pathogenesis to human AIDS. Thus, SIVsm infection of macaques results in AIDS, and similarly experimental inoculation of pigtailed macaques with at least one SIVagm isolate, SIVIhoest or SIVsun, results in AIDS. The extent of plasma viremia in pathogenic infection is an excellent prognostic indicator of clinical course, with higher viral load being predictive of shorter survival and low viremia being predictive of long-term non-progression. Based upon this paradigm, one would have expected naturally infected animals to exhibit low levels of viremia. In reality, AGMs, SMs, mandrills and chimpanzees infected naturally with their own unique viruses display moderate to high levels of plasma viremia. A significant reduction in CD4+ T-cells in infected versus uninfected SMs suggests that the virus may be cytopathic to some degree. These infected animals still maintain adequate CD4+ T-cells over their entire life in captivity. A distinct characteristic of natural infection is the lack of immunopathology as demonstrated by normal lymph node morphology, lower expression of activation and proliferation markers on CD4+ T-cells, and a generally muted immune response to the virus. Naturally infected SMs and AGMs clearly mount antiviral cellular and humoral immune responses. Therefore, models suggesting immune tolerance to SIV are far too simplistic to explain the lack of disease in these animals. It is probable that a unique balance between T-cell renewal and proliferation and loss through activation-induced apoptosis, and virus-induced cell death has been achieved in SMs and AGMs. The study of the dynamics of T-cell production, proliferation and cell death in asymptomatic natural infection should, therefore, yield insights into the pathogenesis of AIDS. 相似文献
33.
Zoref-Shani E Bromberg Y Hirsch J Feinstein S Frishberg Y Sperling O 《Molecular genetics and metabolism》2003,78(2):158-161
We identified a novel point mutation (I137T) in the hypoxanthine-guanine phosphoribosyltransferase (HPRT; EC 2.4.2.8) encoding gene, in a patient with partial deficiency of the enzyme (variant of Lesch-Nyhan syndrome). The mutation, ATT to ACT, resulting in substitution of isoleucine to threonine, occurred at codon 137 (exon 6), which is within the region encoding the binding site for 5-phosphoribosyl-1-pyrophosphate (PRPP). We suggest the mechanism by which the mutation-induced structural alteration of HPRT reduced the affinity of the enzyme for PRPP. 相似文献
34.
Vidarabine versus acyclovir therapy in herpes simplex encephalitis 总被引:35,自引:0,他引:35
R J Whitley C A Alford M S Hirsch R T Schooley J P Luby F Y Aoki D Hanley A J Nahmias S J Soong 《The New England journal of medicine》1986,314(3):144-149
We randomly assigned 208 patients who underwent brain biopsy for presumptive herpes simplex encephalitis to receive either vidarabine (15 mg per kilogram of body weight per day) or acyclovir (30 mg per kilogram per day) for 10 days. Sixty-nine patients (33 percent) had biopsy-proved disease; 37 received vidarabine, and 32 acyclovir. The mortality in the vidarabine recipients was 54 percent, as compared with 28 percent in the acyclovir recipients (P = 0.008). Six-month mortality varied according to the Glasgow coma score at the onset of therapy. For scores of greater than 10, 7 to 10, and less than or equal to 6, mortality was 42, 46, and 67 percent in the patients treated with vidarabine, as compared with 0, 25, and 25 percent in those treated with acyclovir. A six-month morbidity assessment using an adapted scoring system revealed that 5 of 37 patients receiving vidarabine (14 percent) as compared with 12 of 32 receiving acyclovir (38 percent) were functioning normally (P = 0.021). Eight vidarabine-treated patients (22 percent) and three acyclovir-treated patients (9 percent) had moderate debility. Patients under 30 years of age and with a Glasgow coma score above 10 had the best outcome with acyclovir treatment. We conclude that acyclovir is currently the treatment of choice for biopsy-proved herpes simplex encephalitis. 相似文献
35.
Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献
36.
37.
A prospective trial of colchicine for primary biliary cirrhosis 总被引:10,自引:0,他引:10
M M Kaplan D W Alling H J Zimmerman H J Wolfe R A Sepersky G S Hirsch G H Elta K A Glick K A Eagen 《The New England journal of medicine》1986,315(23):1448-1454
We entered 60 patients with primary biliary cirrhosis in a double-blind randomized controlled trial to determine whether colchicine is therapeutically effective. Thirty patients had early disease (Stages 1 and 2), and 30 had advanced disease (Stages 3 and 4). Fifteen patients with early disease and 15 with advanced disease received colchicine (0.6 mg twice daily), and the remainder received placebo. Patients were studied about every two months; those remaining in the blind phase at two years underwent repeat liver biopsy and were then placed on open-label colchicine (0.6 mg twice daily). With a few exceptions, the results in patients with early disease were similar to those in patients with advanced disease; hence, data on patients in all stages were combined in the main analysis. During the two-year study period the colchicine-treated patients, as compared with the placebo-treated patients, had improvement in levels of serum albumin, serum bilirubin, alkaline phosphatase, cholesterol, and aminotransferases. However, there was no such improvement in the severity of symptoms or physical findings; moreover, there was no significant difference in the histologic changes noted at liver biopsy in the two treatment groups. At four years after entry, the cumulative mortality from liver disease was 21 percent in patients given colchicine and 47 percent in those given placebo (P = 0.05). The only side effect of colchicine was diarrhea, noted in three patients. The consistent and significant improvement in a number of markers of liver disease and the apparent decreased mortality from liver disease suggest that colchicine may provide some long-term clinical benefit in patients with primary biliary cirrhosis. However, the failure of colchicine to reduce hepatic inflammation and fibrosis leaves uncertain the effect of the drug on the longterm outcome of this disease. 相似文献
38.
H. Hirsch H. Scholl K. G. Paschke H. Schmid-Schönbein 《Pflügers Archiv : European journal of physiology》1968,301(4):334-343
Zusammenfassung Die corticale Gleichspannung wurde an isolierten Hundeköpfen von der Konvexität des Gehirns (Gyrus lateralis) gegen Nase (Knochenoberfläche des os frontale) bei kompletter und inkompletter Gehirnischämie gemessen.Während kompletter Gehirnischämie verschiebt sich die Gleichspannung nach einer initialen Positivierung, die 1,5–2,75 min nach Ischämiebeginn ein Maximum von 1,5–2 mV erreicht, in negativer Richtung. Diese Negativierung erreicht 3–8 min nach Ischämiebeginn einen steady state von im Mittel 6,5 mV. Nach Ende der kompletten Gehirnischämie kommt es nach einer kurzfristigen Positivierung zu einer länger dauernden Negativierung.Bei inkompletter Gehirnischämie kommt es zu einer Negativierung der Gleichspannung, wenn der Blutdruck auf 80–40 mm Hg abgefallen ist. Es wird vermutet, daß die Negativierung bei der für das Gehirn kritischen Blutdruckhöhe beginnt.Auszugsweise vorgetragen auf der 31. Tagung der Deutschen Physiologischen Gesellschaft Würzburg 1966 [Pflügers Arch. ges. Physiol. 289, R 5 (1966)]. 相似文献
39.
Electrical stimulations were applied daily for 40 days to the dorsal tegmentum in 9 rats through chronically implanted bipolar electrodes. The intensity of current (2 s trains of 50 Hz, 1 ms monophasic square waves) necessary to trigger a full tonic seizure was determined and applied for all further stimulations. Initial stimulations induced a tonic seizure with a low voltage fast electrocorticographic activity. After repeated stimulations, high amplitude spike and wave discharges developed over the cortex, their duration exceeding 50 s at the 40th stimulation. Simultaneously, the tonic seizures evolved into tonic-clonic fits with bilateral myoclonias following the tonic phase. These EEG and behavioral modifications persisted for 30 days after the last stimulus. These results demonstrate that kindling may be obtained from brainstem structures. 相似文献
40.
Dr. L. Kutinová Š. Němečková E. Hamšíková M. Press H. Závadová I. Hirsch V. Němeček V. Krchňák J. Smrt D. Slonim V. Vonka 《Archives of virology》1990,112(3-4):181-193
Summary Several vaccinia virus recombinants inducing the synthesis of the middle surface (M) protein of hepatitis B virus (HBV) were constructed. One of them, denoted vl37, was examined in some detail. The virus replicated nearly to the same extent in various cell lines, viz. human embryo diploid fibroblast LEP and MRC-5 cells, rabbit embryo fibroblast REF cells, TK– rat RAT-2 cells, and green monkey CV-1 cells. However, the production of M protein was found considerably lower in the human LEP and MRC-5 than in the other cells examined. In addition, the kinetics of M formation were different in these two cell systems, LEP cells lagging significantly behind CV-1 cells. The low-level production of M protein in LEP cells was not increased by repeated vl37 passages in LEP cells, nor by a passage in a laboratory worker accidentally infected with the vl37 virus, nor by shortening the leader sequence preceding the translation initiation codon. The greater part of the M antigen was found to be cell associated, more so in the cells of human than monkey origin. From the major HBV S antigen (HBsAg) isolated from the plasma of chronically infected subjects, the antigen released by cell destruction differed by binding to polymerized human albumin. This property was utilized in ELISA to detect anti-preS2 antibody. Rabbits inoculated intradermally with the vl37 virus developed antibodies reactive in this assay as well as with a synthetic peptide corresponding in the amino acids 14–34 of the NH2terminus of the HBsAg preS2 region. 相似文献