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991.
William E Berger Linda B Ford Todd Mahr Robert A Nathan Courtney Crim Lisa Edwards Donna S Wightman William R Lincourt Kathleen Rickard 《Annals of allergy, asthma & immunology》2002,89(4):393-399
BACKGROUND: Studies have shown fluticasone propionate (FP) 100, 200, and 500 microg administered once daily to be effective in the treatment of asthma. The efficacy of a once daily regimen of FP 250 microg has not been evaluated previously. OBJECTIVE: We sought to evaluate the efficacy and safety of inhaled FP 250 microg administered once daily in patients currently receiving inhaled short-acting beta-agonists (SABA) alone or inhaled corticosteroids (ICS). METHODS: In two separate studies, 408 patients in the SABA study and 401 patients in the ICS study were randomly assigned to receive FP 250 microg or placebo for 12 weeks through the Diskus device (GlaxoSmithKline, Research Triangle Park, NC) each morning. RESULTS: At the study endpoint, SABA patients treated with FP and placebo had mean increases in forced expiratory volume in 1 second from baseline of 0.23 +/- 0.03 L and 0.10 +/- 0.03 L, respectively (P < 0.001). ICS patients treated with FP had a mean increase of 0.08 +/- 0.02 L compared with a decrease in forced expiratory volume in 1 second of -0.08 +/- 0.03 L with placebo (P < 0.001). Changes of similar magnitude in morning peak expiratory flow rates were seen with FP in both the SABA and ICS studies. Fewer FP-treated ICS study patients were withdrawn from the study as a result of predetermined asthma stability criteria and, therefore, those patients had a greater probability of remaining in the study than placebo-treated patients (P < 0.001). CONCLUSIONS: FP 250 microg, once daily, produced greater improvements in pulmonary function and asthma symptom control than placebo. This new treatment regimen provides clinicians with an additional therapeutic option for patients with asthma previously treated with either beta2-agonists alone or ICS. 相似文献
992.
Austgulen R Chedwick L Vogt Isaksen C Vatten L Craven C 《Archives of pathology & laboratory medicine》2002,126(12):1480-1486
CONTEXT: Apoptosis occurs in the normal placenta. The monoclonal antibody M30 is directed against a novel epitope of cytokeratin 18 (CK18) that is formed by caspase cleavage early in the apoptotic cascade, and this antibody may therefore be useful for evaluating trophoblast apoptosis. OBJECTIVE: We undertook the present study to evaluate the use of monoclonal antibody M30 to assess trophoblast apoptosis in placenta at term. METHODS: We stained paraffin-embedded placental tissues from 15 deliveries at term with M30. We compared positive M30 staining and CK18 staining (as detected by a monoclonal antibody directed against CK18) of trophoblasts in serial slides. We also compared apoptotic rates as detected by M30 and TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling) in 7 of the placentas. RESULTS: In fields of villous tissue, most M30-positive cells were CK18-positive syncytiotrophoblasts. Approximately half of M30-positive cells occurred as focal positive staining in the syncytial layer, and half occurred as abundant staining of syncytiotrophoblasts in areas with increased intervillous or perivillous fibrinoid. We found very few M30-positive cells in villous stroma. In decidual/basal plate tissues, most (two thirds) of the M30-positive cells were CK18-positive extravillous trophoblasts, whereas one third were syncytiotrophoblasts of anchoring villi. Since TUNEL detects apoptosis in both epithelial and nonepithelial cells, more cells were positively stained with TUNEL than with M30 in some tissue fields. However, our observations suggest that M30 was more sensitive than TUNEL in recognizing apoptotic trophoblasts and had less nonspecific staining than TUNEL. CONCLUSION: We recommend the use of monoclonal antibody M30 for apoptosis studies in placental tissues. This antibody is easy to handle, the staining obtained seems specific, and the nonspecific staining seems negligible. 相似文献
993.
994.
Sulkowski MS Felizarta F Smith C Slim J Berggren R Goodman R Ball L Khalili M Dieterich DT;Hepatitis Resource Network Clinical Trials Group 《Journal of acquired immune deficiency syndromes (1999)》2004,35(5):464-472
Among HIV-infected persons, chronic hepatitis C virus (HCV) infection causes substantial morbidity and mortality. However, few studies have evaluated the safety and efficacy of interferon alfa (IFN) and ribavirin (RBV) therapy in co-infected persons. Accordingly, a randomized, controlled, open-label, multicenter trial was conducted to establish the safety, tolerability, and efficacy of IFN alfa-2b 3 mIU daily plus RBV 800 mg/d compared with IFN alfa-2b 3 mIU thrice weekly (TIW) plus RBV 800 mg/d in HCV treatment-naive, HIV-infected subjects with compensated liver disease and stable HIV disease. The primary endpoint was sustained virologic response (SVR), defined as an undetectable HCV RNA level 24 weeks after discontinuation of HCV therapy. At study entry, subjects in both groups were similar with respect to age, gender, HCV genotype, and HIV disease status. Of 180 randomized subjects, 162 received at least 1 dose of study medication, constituting the modified intention-to-treat population. After 12 weeks of therapy, 122 (75%) had serum HCV RNA levels assessed; of these subjects, early virologic response (undetectable HCV RNA or >2 log10 decrease from baseline) was observed in 33 (42%) and 13 (16%) of subjects taking daily and TIW IFN, respectively (P < 0.001). SVR was observed in 15 (19.0%) and 7 (8.4%) of subjects taking daily and TIW IFN, respectively (P = 0.05). Adverse events were similar in both groups. However, while no deaths or opportunistic infections were observed, nearly 30% of subjects stopped treatment due to adverse events and 7 subjects experienced a serious adverse event. In conclusion, SVR was achieved in 19% of HIV/HCV coinfected subjects treated with daily IFN plus RBV, but the effectiveness of therapy was substantially diminished by relatively high rates of treatment-related toxicity. 相似文献
995.
Nowaczyk MJ Martin-Garcia D Aquino-Perna A Rodriguez-Vazquez M McCaughey D Eng B Nakamura LM Waye JS 《American journal of medical genetics. Part A》2004,(2):173-176
Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive MCA-MR disorder caused by mutations within the 7-dehydrocholesterol reductase gene, DHCR7. The diagnosis is based on the biochemical findings of elevated plasma 7-dehydrocholesterol (7DHC) levels. It is a panethnic condition with variable mutation frequencies in different populations. Ten Cuban patients and four Canadian patients of Mediterranean ancestry with SLOS are reported herein. All these patients are at the mild end of the clinical spectrum (the highest Kelley-Hennekam severity score was 28 in one patient). All patients had genotypes which were compound heterozygous or homozygous for T93M; in all the Mediterranean patients the T93M mutation appeared to be associated with the J haplotype. Another compound heterozygote for T93M was of Ukrainian/Irish ancestry; in this patient the T93M was associated with a new haplotype designated K. The T93M mutation was initially reported as the most common in a series of patients from Italy. Our identification of a single haplotype associated with the T93M mutation in patients whose ancestors originate in the region of the Mediterranean Sea basin suggests a founder effect. 相似文献
996.
Kamya MR Semitala FC Quinn TC Ronald A Njama-Meya D Mayanja-Kizza H Katabira ET Spacek LA 《African health sciences》2004,4(2):94-101
Introduction
Total Lymphocyte Count (TLC) has been found to be an inexpensive and useful marker for staging disease, predicting progression to AIDS and death and monitoring response to ART. However, the correlation between TLC and CD4 has not been consistent. Access to HAART is expanding in Kampala, Uganda, yet there are no published data evaluating the utility of TLC as inexpensive surrogate marker of CD4 cell count to help guide therapeutic decisions.Objective
To evaluate clinical illnesses and total lymphocyte count (TLC) as surrogate markers of the CD4 cell count in HIV infected persons being considered for ART.Methods
A total of 131 patients were enrolled and evaluated by clinical assessment, TLC and CD4 count. Clinical illnesses and TLC dichotomized at various cut-point values were used to determine the sensitivity, specificity, and positive and negative predictive values (PPV and NPV) for the diagnosis of CD4 count <200 cells/mm3 among 100 participants fulfilling criteria for WHO clinical stage 2 and 3.Results
A strong correlation was observed between TLC and CD4 (r = 0.73, p<0.0001). For all clinical syndromes, except pulmonary tuberculosis, the positive predictive values (PPV) for a CD4 count <200 cells/mm3 were high (>80%) but the negative predictive values (NPV) were low. Using the WHO recommended TLC cut-off of 1200 cells/mm3 to diagnose a CD4 less than 200 cells/mm3, the PPV was 100%, and the NPV was 32%.Conclusion
Our data showed a good correlation between TLC and CD4 cell count. However, the WHO recommended TLC cutoff of 1200 did not identify the majority of WHO stage 2 and 3 patients with CD4 counts less than 200 cells/mm3. A more rational use of TLC counts is to treat all patients with WHO stage 2 and 3 who have a TLC <1200 and to limit CD4 counts to patients who are symptomatic but have TLC of >1200. 相似文献997.
Differential effects of growth factors on tissue-engineered cartilage 总被引:18,自引:0,他引:18
Blunk T Sieminski AL Gooch KJ Courter DL Hollander AP Nahir AM Langer R Vunjak-Novakovic G Freed LE 《Tissue engineering》2002,8(1):73-84
The effects of four regulatory factors on tissue-engineered cartilage were examined with specific focus on the ability to increase construct growth rate and concentrations of glycosaminoglycans (GAG) and collagen, the major extracellular matrix (ECM) components. Bovine calf articular chondrocytes were seeded onto biodegradable polyglycolic acid (PGA) scaffolds and cultured in medium with or without supplemental insulin-like growth factor (IGF-I), interleukin-4 (IL-4), transforming growth factor-beta1 (TGF-beta1) or platelet-derived growth factor (PDGF). IGF-I, IL-4, and TGF-beta1 increased construct wet weights by 1.5-2.9-fold over 4 weeks of culture and increased amounts of cartilaginous ECM components. IGF-I (10-300 ng/mL) maintained wet weight fractions of GAG in constructs seeded at high cell density and increased by up to fivefold GAG fractions in constructs seeded at lower cell density. TGF-beta1 (30 ng/mL) increased wet weight fractions of total collagen by up to 1.4-fold while maintaining a high fraction of type II collagen (79 plus minus 11% of the total collagen). IL-4 (1-100 ng/mL) minimized the thickness of the GAG-depleted region at the construct surfaces. PDGF (1-100 ng/mL) decreased construct growth rate and ECM fractions. Different regulatory factors thus elicit significantly different chondrogenic responses and can be used to selectively control the growth rate and improve the composition of engineered cartilage. 相似文献
998.
Identification of two phylogenetically related organisms from feces by PCR for detection of Salmonella spp 下载免费PDF全文
Gentry-Weeks C Hutcheson HJ Kim LM Bolte D Traub-Dargatz J Morley P Powers B Jessen M 《Journal of clinical microbiology》2002,40(4):1487-1492
Two previously reported PCR methods were evaluated to determine whether they are as sensitive and specific as conventional culture methods in detecting Salmonella spp. from feces. Bovine and equine feces were enriched overnight in brain heart infusion broth and assayed using PCR methods and primer sets described by other investigators. A total of 774 fecal specimens were tested using a primer set (invE-A primer set) that amplifies a region spanning the invasin E and A genes of Salmonella enterica serovar Typhimurium. A subset of these fecal specimens (306 of the 774 total) were tested using primers (hisJ primer set) that amplify a portion of the histidine transport J gene. The PCR required 24 h to obtain results, whereas it took 5 to 7 days to identify Salmonella spp. by culture. PCR detection of Salmonella spp. using the hisJ primers and the invE-A primers had a sensitivity of 93.3 and 80%, respectively, and a specificity of 85.6 and 98.6%, respectively, compared with bacterial culture. Amplification of 42 culture-negative fecal specimens (of 306 total specimens) generated a DNA fragment that corresponded to the molecular weight of the amplified hisJ gene. The hisJ-generated amplicons from six culture-negative and six culture-positive specimens were sequenced and analyzed using DNA sequence alignment and phylogenetic analysis software. A neighbor-joining dendrogram of the DNA sequences of both sets of hisJ amplicons revealed two distinct groups-one group of amplicons from culture-positive specimens identical to the hisJ gene of S. enterica serovar Typhimurium and a second group of amplicons from culture-negative specimens that were more closely related to hisJ of S. enterica serovar Typhimurium than to other hisJ sequences present in nucleotide databases. 相似文献
999.
Vaccination of pregnant dams with intimin(O157) protects suckling piglets from Escherichia coli O157:H7 infection 总被引:3,自引:0,他引:3 下载免费PDF全文
Dean-Nystrom EA Gansheroff LJ Mills M Moon HW O'Brien AD 《Infection and immunity》2002,70(5):2414-2418
Cattle are important reservoirs of enterohemorrhagic Escherichia coli (EHEC) O157:H7 that cause disease in humans. Both dairy and beef cattle are asymptomatically and sporadically infected with EHEC. Our long-term goal is to develop an effective vaccine to prevent cattle from becoming infected and transmitting EHEC O157:H7 to humans. We used passive immunization of neonatal piglets (as a surrogate model) to determine if antibodies against EHEC O157 adhesin (intimin(O157)) inhibit EHEC colonization. Pregnant swine (dams) with serum anti-intimin titers of < or =100 were vaccinated twice with purified intimin(O157) or sham-vaccinated with sterile buffer. Intimin(O157)-specific antibody titers in colostrum and serum of dams were increased after parenteral vaccination with intimin(O157). Neonatal piglets were allowed to suckle vaccinated or sham-vaccinated dams for up to 8 h before they were inoculated with 10(6) CFU of a Shiga toxin-negative (for humane reasons) strain of EHEC O157:H7. Piglets were necropsied at 2 to 10 days after inoculation, and intestinal samples were collected for determination of bacteriological counts and histopathological analysis. Piglets that ingested colostrum containing intimin(O157)-specific antibodies from vaccinated dams, but not those nursing sham-vaccinated dams, were protected from EHEC O157:H7 colonization and intestinal damage. These results establish intimin(O157) as a viable candidate for an EHEC O157:H7 antitransmission vaccine. 相似文献
1000.
Characterization of the in vivo function of TNF-alpha-related apoptosis-inducing ligand,TRAIL/Apo2L,using TRAIL/Apo2L gene-deficient mice 总被引:11,自引:0,他引:11
Sedger LM Glaccum MB Schuh JC Kanaly ST Williamson E Kayagaki N Yun T Smolak P Le T Goodwin R Gliniak B 《European journal of immunology》2002,32(8):2246-2254
To define the normal physiological role for the TRAIL/Apo2L in vivo, we generated TRAIL/Apo2L gene-targeted mice. These mice develop normally and show no defects in lymphoid or myeloid cell homeostasis or function. Although TRAIL/Apo2L kills transformed cells in vitro, TRAIL/Apo2L(-/-) mice do not spontaneously develop overt tumors at an early age. However, in the A20 B cell lymphoma-transferred tumor model, TRAIL/Apo2L(-/-) mice are clearly more susceptible to death from overwhelming tumor burden, due to increased lymphoma load in the liver. A20 tumors are susceptible to TRAIL/Apo2L killing in vitro, indicating that TRAIL/Apo2L may act directly to control A20 cells in vivo. Despite the fact that TRAIL binds osteoprotegerin and osteoprotegerin-transgenic mice are osteopetrotic, TRAIL/Apo2L(-/-) mice show no evidence of altered gross bone density, and no alterations in frequency or in vitro differentiation of bone marrow precursor osteoclasts. Moreover, leucine zipper TRAIL has no toxicity when repeatedly administered to osteoprotegerin(-/-) mice. Thus, TRAIL/Apo2L is important in controlling tumors in vivo, but is not an essential regulator of osteoprotegerin-mediated biology, under normal physiological conditions. 相似文献