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41.
Berhane K Karim R Cohen MH Masri-Lavine L Young M Anastos K Augenbraun M Watts DH Levine AM 《Journal of acquired immune deficiency syndromes (1999)》2004,37(2):1245-1252
BACKGROUND: Anemia is common in HIV-infected individuals and may be associated with decreased survival. OBJECTIVE: To ascertain the impact of highly active antiretroviral therapy (HAART) on anemia and the relationship between anemia and overall survival in HIV-infected women. METHODS: A prospective multicenter study of HIV-1 infection in women. Visits occurred every 6 months, including a standardized history, physical examination, and comprehensive laboratory evaluation. The setting was a university-affiliated clinic at 6 sites in the United States. Participants were 2056 HIV-infected women from the Women's Interagency HIV Study (WIHS). The outcome measure was anemia, defined as hemoglobin (Hb) <12 g/dL. Survival analysis was based on overall mortality during the follow-up period. RESULTS: Among HIV-infected women who were not anemic at baseline, 47% became anemic by 3.5 years of follow-up. On multivariate analysis, the use of HAART was associated with resolution of anemia even when used for only 6 months (odds ratio [OR] = 1.45; P < 0.05). In the multivariate model, a CD4 cell count <200 cells/microL (OR = 0.56; P < 0.001); HIV-1 RNA level > or =50,000 copies/mL (OR = 0.65; P < 0.001), and mean corpuscular volume (MCV) value <80 fL (OR = 0.40; P < 0.001) were also associated with an inability to correct anemia. Similarly, use of HAART for 12 months or more was associated with a protective effect against development of anemia (OR = 0.71; P < 0.001). Among HIV-infected women, anemia was independently associated with decreased survival (hazard ratio [HR] = 2.58; P < 0.001). Other factors associated with decreased survival included a CD4 cell count <200 cells/microL (HR = 5.83; P < 0.001), HIV-1 RNA level > or = 50,000 copies/mL (HR = 2.12; P < 0.001), and clinical diagnosis of AIDS (HR = 2.83; P < 0.001). CONCLUSIONS: Anemia is an independent risk factor for decreased survival among HIV-infected women. HAART therapy for as little as 6 months is associated with resolution of anemia. 相似文献
42.
Large-scale screening of nasal swabs for Bacillus anthracis: descriptive summary and discussion of the National Institutes of Health's experience 下载免费PDF全文
Kiratisin P Fukuda CD Wong A Stock F Preuss JC Ediger L Brahmbhatt TN Fischer SH Fedorko DP Witebsky FG Gill VJ 《Journal of clinical microbiology》2002,40(8):3012-3016
In October 2001, a letter containing a large number of anthrax spores was sent through the Brentwood post office in Washington, D.C., to a United States Senate office on Capitol Hill, resulting in contamination in both places. Several thousand people who worked at these sites were screened for spore exposure by collecting nasal swab samples. We describe here a screening protocol which we, as a level A laboratory, used on very short notice to process a large number of specimens (3,936 swabs) in order to report preliminary results as quickly as possible. Six isolates from our screening met preliminary criteria for Bacillus anthracis identification and were referred for definitive testing. Although none of the isolates was later confirmed to be B. anthracis, we studied these isolates further to define their biochemical characteristics and 16S rRNA sequences. Four of the six isolates were identified as Bacillus megaterium, one was identified as Bacillus cereus, and one was an unidentifiable Bacillus sp. Our results suggest that large-scale nasal-swab screening for potential exposure to anthrax spores, particularly if not done immediately postexposure, may not be very effective for detecting B. anthracis but may detect a number of Bacillus spp. that are phenotypically very similar to B. anthracis. 相似文献
43.
Ochiai Y Golding LA Massiello AL Medvedev AL Horvath DJ Gerhart RL Chen JF Krogulecki AY Takagaki M Doi K Howard MW Fukamachi K 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(3):249-252
The Cleveland Clinic CorAide left ventricular assist system consists of a permanently implantable centrifugal pump in which the rotating assembly is completely suspended and noncontacting. A series of chronic animal in vivo studies were conducted to evaluate the biologic effects of CorAide circulatory support without the use of anticoagulation therapy. The CorAide pump was implanted in six calves (five calves for 21 to 32 days and one calf for 95 days). The first five calves received intravenous heparin during the early postoperative periods (2-7 days). Heparin administration was then discontinued and no other anticoagulant drugs were used for the duration of the experiments. The last calf did not receive any anticoagulant except for a bolus dose of heparin (200 U/kg) during surgery. Hemodynamics were stable in all six calves, with a mean pump flow of 5.6+/-1.2 L/min and mean arterial pressure of 100+/-4 mm Hg. The blood pump surfaces were clean of thrombus in all six calves. Significant findings at autopsy were limited to one case of renal infarction. There was no incidence of mechanical failure, bleeding, or device infection. The CorAide pump can be safely run with minimal or no anticoagulant therapy. 相似文献
44.
Anne-christine Jauneau Alexander Ischenko Alexandra Chatagner Magalie Benard Philippe Chan Marie-therese Schouft Christine Patte Hubert Vaudry Marc Fontaine 《Journal of neuroinflammation》2006,3(1):8-10
C3a and C5a anaphylatoxins are proinflammatory polypeptides released during complement activation. They exert their biological
activities through interaction with two G protein-coupled receptors named C3aR and C5aR, respectively. In the brain, these
receptors are expressed on glial cells, and some recent data have suggested that anaphylatoxins could mediate neuroprotection.
In this study, we used RT-PCR and ribonuclease protection assays (RPA) to investigate the role of anaphylatoxins on neurotrophin
expression by the human glioblastoma cell line T98G and by rat astrocytes. Our data show that for both cell types, anaphylatoxins
upregulate expression of NGF mRNA. This response depended on a G protein-coupled pathway since pre-treatment of cells with
pertussis toxin (PTX) completely blocked NGF mRNA increases. This effect was anaphylatoxin-specific since pre-incubation with
anti-C3a or anti-C5aR antibodies abolished the effects of C3a and C5a, respectively. The regulation of NGF mRNA by anaphylatoxins
was not accompanied by translation into protein expression, but there was a significant synergic effect of anaphylatoxins/IL-1b
costimulation. Our demonstration of involvement of anaphylatoxins in the NGF release process by astrocytes suggests that C3a
and C5a could modulate neuronal survival in the CNS. 相似文献
45.
Peptide-pulsed splenic dendritic cells prime long-lasting CD8(+) T cell memory in the absence of cross-priming by host APC. 总被引:2,自引:0,他引:2
Immunization with cells expressing endogenous antigens can stimulate long-lived CD8(+) T cell memory. In many cases, the response is also stimulated by host antigen-presenting cells (APC) that have processed antigen from internalized apoptotic cells or cell fragments. This study investigated whether immunization with peptide-pulsed dendritic cells (DC) could prime long-lasting, peptide-specific CD8(+) T cell immunity in the absence of cross-priming by host APC. C57BL / 6 female mice immunized with syngeneic male splenic DC pulsed with the H-2K(b)-restricted ovalbumin peptide OVA(257 - 264) made memory CD8(+) CD44(high) T cell responses to OVA(257 - 264) and the male antigen HY more than 1 year after immunization. Establishment and maintenance of peptide-specific CD8(+) T cell memory did not require antibody or B cells. Immunization of H-2(bxd) mice with OVA(257 - 264)-pulsed minor-incompatible H-2(b) or H-2(d) DC demonstrated that CD8(+) T cells were primed exclusively by the injected cells, and not by peptide transferred to host APC, even though there was very effective cross-priming for CD8(+) T cell responses to the minor antigens expressed by the DC. Thus peptide-pulsed DC can prime long-lasting CD8(+) memory responses without any requirement for cross-priming by other APC. 相似文献
46.
Cardoso O Leitão R Figueiredo A Sousa JC Duarte A Peixe LV 《Microbial drug resistance (Larchmont, N.Y.)》2002,8(2):93-97
Resistance to carbapenems is emerging, and it is a great problem to therapeutics. Three isolates of Pseudomonas aeruginosa from a Portuguese hospital identified in urine and sputum, in 1995, presented a high-level resistance to imipenem (> 32 mg/L). Afterward, one isolate of P. aeruginosa recovered from urine of an ambulatory patient in 1998 showed high resistance to imipenem and meropenem. The resistance to carbapenems in these strains was associated with the production of a class B beta-lactamase, as was demonstrated by imipenem hydrolysis and inhibition by EDTA. Using primers described for bla(IMP) and bla(VIM), the amplification of the latter was observed in all isolates and a VIM-2 metallo-enzyme was identified. The pulsed-field gel electrophoresis (PFGE) patterns of these isolates were indistinguishable, suggesting dissemination to the community of this VIM-2 producer. 相似文献
47.
Hematopoietic progenitor cells and cellular microenvironment: behavioral and molecular changes upon interaction 总被引:2,自引:0,他引:2
Wagner W Saffrich R Wirkner U Eckstein V Blake J Ansorge A Schwager C Wein F Miesala K Ansorge W Ho AD 《Stem cells (Dayton, Ohio)》2005,23(8):1180-1191
Cell-cell contact between stem cells and cellular determinants of the microenvironment plays an essential role in controlling cell division. Using human hematopoietic progenitor cells (CD34+/CD38-) and a stroma cell line (AFT024) as a model, we have studied the initial behavioral and molecular sequel of this interaction. Time-lapse microscopy showed that CD34+/CD38- cells actively migrated toward and sought contact with stroma cells and 30% of them adhered firmly to AFT024 stroma through the uropod. CD44 and CD34 are colocalized at the site of contact. Gene expression profiles of CD34+/CD38- cells upon cultivation with or without stroma for 16, 20, 48, or 72 hours were analyzed using our human genome cDNA microarray. Chk1, egr1, and cxcl2 were among the first genes upregulated within 16 hours. Genes with the highest upregulation throughout the time course included tubulin genes, ezrin, c1qr1, fos, pcna, mcm6, ung, and dnmt1, genes that play an essential role in reorganization of the cytoskeleton system, stabilization of DNA, and methylation patterns. Our results demonstrate directed migration of CD34+/CD38- cells toward AFT024 and adhesion through the uropod and that upon interaction with supportive stroma, reorganization of the cytoskeleton system, regulation of cell division, and maintenance of genetic stability represent the most essential steps. 相似文献
48.
49.
Indolent systemic mastocytosis with elevated serum tryptase, absence of skin lesions, and recurrent severe anaphylactoid episodes 总被引:2,自引:0,他引:2
Florian S Krauth MT Simonitsch-Klupp I Sperr WR Fritsche-Polanz R Sonneck K Födinger M Agis H Böhm A Wimazal F Horny HP Valent P 《International archives of allergy and immunology》2005,136(3):273-280
BACKGROUND: In contrast to aggressive mastocytosis, patients with indolent systemic mastocytosis (ISM) usually present with urticaria pigmentosa-like skin lesions. In those who lack skin lesions, mastocytosis is often overlooked or confused with endocrinologic, allergic, or other internal disorders. CASE REPORT AND RESULTS: We report on a 33-year-old male patient in whom severe hypotensive episodes occurred after contact with ants or yellow jackets. Since no specific IgE was detected, the serum tryptase concentration was measured and found to be clearly elevated (70 ng/ml). Consecutive staging and examination of the bone marrow revealed ISM. The patient was advised to circumvent insect contact, to take antihistamines on demand, and to carry an epinephrine self-injector for emergency events. In a retrospective analysis of 40 patients seen between 1988 and 2003, only 2 had a life-threatening mediator-related episode before ISM was diagnosed. CONCLUSIONS: Our report confirms the diagnostic value of tryptase in patients with suspected mastocytosis. In addition, the report suggests that the lack of typical skin lesions does not exclude an indolent form of mastocytosis even if the serum tryptase is clearly elevated. Finally, our case further shows that mastocytosis can be an important differential diagnosis to be considered in patients with unexplained anaphylactoid or other mediator-related symptoms. 相似文献
50.