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101.
TD de Gruijl HJ Bontkes JM Walboomers JT Schiller MJ Stukart BS Groot MM Chabaud AJ Remmink RH Verheijen TJ Helmerhorst CJ Meijer RJ Scheper 《Canadian Metallurgical Quarterly》1997,89(9):630-638
BACKGROUND: Infection with cancer-linked human papillomavirus (HPV) types such as HPV type 16 (HPV16) is the most important risk factor in the development of cervical cancer. It has been shown that immunoglobulin G (IgG) antibody responses against HPV16 virus-like particles (VLPs) are specifically associated with genital HPV16 infection. PURPOSE: The aim of this study was to determine the temporal relationships between the presence of HPV16 VLP-specific IgGs, HPV16 infection patterns, and the course of premalignant cervical disease. METHODS: Plasma samples from 133 women who had been diagnosed originally with mild to moderate cervical dyskaryosis and enrolled in a prospective non-intervention cohort study conducted in Amsterdam, The Netherlands, from 1991 through 1996 were analyzed for the presence of HPV16 VLP-specific IgGs by use of an enzyme-linked immunosorbent assay. A detailed analysis was performed on 43 women with different HPV16 infection patterns during a follow-up period of 10-34 months. Progression or regression of cervical intraepithelial neoplasia (CIN) lesions was monitored by cytologic and colposcopic testing at intervals of 3-4 months. HPV typing in cervical smears was performed by use of a polymerase chain reaction-based assay. Statistical analysis of the serologic data was performed by use of the Mann-Whitney U test or 2 x 2 table analyses. RESULTS: The presence of HPV16 VLP-specific IgGs in the plasma of the patients was found to be associated with the presence of HPV16 DNA in the cervical smear. Significantly higher proportions of patients with persistent HPV16 infections (i.e., who were polymerase chain reaction positive in three to 11 consecutive tests) than of patients with cleared HPV16 infections were found to be positive for the presence of HPV16 VLP-specific IgGs (18 [69.2%] of 26 versus nine [28.1%] of 32, respectively; P = .003). HPV16 VLP-specific IgGs were consistently detected in all women (n = 11) who were persistently HPV16 DNA positive during follow-up and whose disease ultimately progressed to CIN III (histologically diagnosed severe dysplasia or carcinoma in situ). CONCLUSION: HPV16 VLP-specific IgG responses are present in the plasma of a majority of patients with persistent HPV16 infections and histologically confirmed high-grade lesions but only in a smaller subset of patients with cleared HPV16 infections and either normal cervical histology or low-grade CIN lesions. IMPLICATIONS: These results suggest that HPV16 VLP-specific antibodies are not responsible for the clearance of virally induced CIN lesions but that they might, in patients with persistent HPV16 infections, be indicative of an increased cervical cancer risk. 相似文献
102.
BS Chertow HK Driscoll NQ Goking D Primerano MB Cordle KA Matthews 《Canadian Metallurgical Quarterly》1997,46(6):656-660
OBJECTIVE: We evaluated the influence of chronic blockade of the renin-angiotensin system on hypertension induced by long-term thyroxin (T4) administration. To this end, we determined the effects of chronic treatment with captopril on blood pressure, cardiac hypertrophy and other renal and metabolic variables of hypertensive hyperthyroid rats. METHODS: T4 was administered s.c. at 0.38 mumol/kg per day and captopril was given in the drinking water (1.38 mmol/l). Both treatments were maintained for 6 weeks. Control rats received tap water. After the treatment period, the rats were placed in metabolic cages. Later, blood pressure was measured in conscious rats by intra-arterial determination. RESULTS: T4-treated rats showed an increased mean arterial pressure (MAP) whereas, in rats treated with T4 plus captopril, MAP was similar to that of the control group. Captopril did not affect the increased heart rate or ventricular weight/body weight ratio of hyperthyroid rats, but it improved the reduced creatinine clearance of these animals. CONCLUSIONS: The elevation in blood pressure produced by long-term T4 administration was prevented by chronic blockade of the renin-angiotensin system. Captopril improved the renal function of hyperthyroid rats, but did not affect the relative cardiac hypertrophy of these animals. 相似文献
103.
GL Fraser P Stogsdill JD Dickens DE Wennberg RP Smith BS Prato 《Canadian Metallurgical Quarterly》1997,157(15):1689-1694
BACKGROUND: Although numerous reports have described interventions designed to influence antibiotic utilization, to our knowledge none have been evaluated in a randomized study. METHODS: Adult inpatients receiving 1 or more of 10 designated parenteral antibiotics for 3 or more days during a 3-month period were randomized to an intervention (n = 141) and a control (n = 111) group using an unblocked, computer-generated random number table. Obstetric patients and those seen in infectious disease consultation were excluded. The intervention group received antibiotic-related suggestions from a team consisting of an infectious disease fellow and a clinical pharmacist. Both groups were evaluated for clinical and microbiological outcomes as well as antibiotic utilization via prospective chart reviews and analysis of the hospital's administrative database. RESULTS: Sixty-two (49%) of the intervention group patients received a total of 74 suggestions. Sixty-three (84%) of these suggestions were implemented; the majority involved changes in antibiotic choice, dosing regimen, or route of administration. Per patient antibiotic charges were nearly $400 less in the intervention group vs controls (P = .05). Almost all the savings were related to lower intravenous antibiotic charges. Clinical and microbiological response, antibiotic-associated toxic effects, in-hospital mortality, and readmission rates were similar for both groups. Multiple linear regression analysis identified randomization to the intervention group and female sex as the sole predictors of lower antibiotic charges. There was a trend toward a shorter length of stay for the intervention group (20 vs 24.7 days, P = .11). CONCLUSIONS: This is the first randomized study to evaluate whether antibiotic choices can be influenced in a cost-effective fashion without sacrificing patient safety. We demonstrate that 50% of patients initially treated with expensive parenteral antibiotics can have their regimens refined after 3 days of therapy and that these modifications result in good clinical outcomes with a substantial reduction in antibiotic expense. 相似文献
104.
105.
Ramos-Padrón E Bordenave S Lin S Bhaskar IM Dong X Sensen CW Fournier J Voordouw G Gieg LM 《Environmental science & technology》2011,45(2):439-446
Oil sands tailings ponds receive and store the solid and liquid waste from bitumen extraction and are managed to promote solids densification and water recycling. The ponds are highly stratified due to increasing solids content as a function of depth but can be impacted by tailings addition and removal and by convection due to microbial gas production. We characterized the microbial communities in relation to microbial activities as a function of depth in an active tailings pond routinely treated with gypsum (CaSO(4)·2H(2)O) to accelerate densification. Pyrosequencing of 16S rDNA gene sequences indicated that the aerobic surface layer, where the highest level of sulfate (6 mM) but no sulfide was detected, had a very different community profile than the rest of the pond. Deeper anaerobic layers were dominated by syntrophs (Pelotomaculum, Syntrophus, and Smithella spp.), sulfate- and sulfur-reducing bacteria (SRB, Desulfocapsa and Desulfurivibrio spp.), acetate- and H(2)-using methanogens, and a variety of other anaerobes that have been implicated in hydrocarbon utilization or iron and sulfur cycling. The SRB were most abundant from 10 to 14 mbs, bracketing the zone where the sulfate reduction rate was highest. Similarly, the most abundant methanogens and syntrophs identified as a function of depth closely mirrored the fluctuating methanogenesis rates. Methanogenesis was inhibited in laboratory incubations by nearly 50% when sulfate was supplied at pond-level concentrations suggesting that in situ sulfate reduction can substantially minimize methane emissions. Based on our data, we hypothesize that the emission of sulfide due to SRB activity in the gypsum treated pond is also limited due to its high solubility and oxidation in surface waters. 相似文献
106.
BS Kwon S Wang N Udagawa V Haridas ZH Lee KK Kim KO Oh J Greene Y Li J Su R Gentz BB Aggarwal J Ni 《Canadian Metallurgical Quarterly》1998,12(10):845-854
A newly identified member of the tumor necrosis factor receptor (TNFR) superfamily shows activities associated with osteoclastogenesis inhibition and fibroblast proliferation. This new member, called TR1, was identified from a search of an expressed sequence tag database, and encodes 401 amino acids with a 21-residue signal sequence. Unlike other members of TNFR, TR1 does not contain a transmembrane domain and is secreted as a 62 kDa glycoprotein. TR1 gene maps to chromosome 8q23-24.1 and its mRNA is abundantly expressed on primary osteoblasts, osteogenic sarcoma cell lines, and primary fibroblasts. The receptors for TR1 were detected on a monocytic cell line (THP-1) and in human fibroblasts. Scatchard analyses indicated two classes of high and medium-high affinity receptors with a kD of approximately 45 and 320 pM, respectively. Recombinant TR1 induced proliferation of human foreskin fibroblasts and potentiated TNF-induced proliferation in these cells. In a coculture system of osteoblasts and bone marrow cells, recombinant TR1 completely inhibited the differentiation of osteoclast-like multinucleated cell formation in the presence of several bone-resorbing factors. TR1 also strongly inhibited bone-resorbing function on dentine slices by mature osteoclasts and decreased 45Ca release in fetal long-bone organ cultures. Anti-TR1 monoclonal antibody promoted the formation of osteoclasts in mouse marrow culture assays. These results indicate that TR1 has broad biological activities in fibroblast growth and in osteoclast differentiation and its functions. 相似文献
107.
JI Hudson SL McElroy NC Raymond S Crow PE Keck WP Carter JE Mitchell SM Strakowski HG Pope BS Coleman JM Jonas 《Canadian Metallurgical Quarterly》1998,155(12):1756-1762
OBJECTIVE: The purpose of this study was to assess the efficacy of fluvoxamine in the treatment of binge-eating disorder. Binge-eating disorder is a newly described eating disorder characterized by recurrent episodes of binge eating but without purging behaviors. Uncontrolled reports have suggested that serotonin selective reuptake inhibitors (SSRIs) may be effective in treating this disorder. METHOD: Eighty-five outpatients with a DSM-IV diagnosis of binge-eating disorder were randomly assigned to receive either fluvoxamine (N=42) or placebo (N=43) in a 9-week, parallel-group, double-blind, flexible dose (50-300 mg) study at three centers. The primary outcome measures were frequency of binge eating, expressed as log ([binges/week]+1), and Clinical Global Impression (CGI) scale ratings. Secondary measures included the level of response (based on the percentage change in frequency of binges), body mass index, and Hamilton Rating Scale for Depression score. Except for the level of response, the outcome measures were analyzed by random regression methods; the treatment-by-time interaction was the measure of treatment effect. RESULTS: Compared with placebo, fluvoxamine was associated with a significantly greater rate of reduction in the frequency of binges, rate of reduction in CGI severity scores, rate of increase in CGI improvement scores, level of response for patients who completed the 9-week study, and rate of reduction in body mass index. There was no significant difference between placebo and fluvoxamine groups in the rate of decrease in Hamilton depression scale scores. A significantly greater proportion of patients receiving fluvoxamine than those receiving placebo discontinued treatment because of an adverse medical event. CONCLUSIONS: In this placebo-controlled trial, fluvoxamine was found to be effective according to most outcome measures in the acute treatment of binge-eating disorder. 相似文献
108.
BS Weeks M Nomizu A Otaka CA Weston A Okusu H Tamamura N Yamamoto N Fujii 《Canadian Metallurgical Quarterly》1995,215(2):626-631
The [Tyr5,12,Lys7]-polyphemusin II peptide (T22) inhibits HIV-1 replication in lymphocytes. The mechanism of T22 inhibition of HIV-1 replication may involve T22 competition with HIV-1 for attachment sites on the plasma membrane of targeted cells. Here we find that the T22 peptide binds to the CD4 molecule in affinity columns. We also find that antiserum to CD4 inhibits cell attachment to T22. Further CD4+ transfected cells attach to T22 while their parental cells which do not express CD4 do not attach to T22. These data demonstrate that T22 binds to the CD4 molecule and supports the hypothesis that T22 inhibits HIV-1 replication by binding to the cell surface CD4 molecule and inhibiting uptake of the virus. 相似文献
109.
M Rémy R Bareille F Villars F Rouais A Gorodkov L Bordenave 《Canadian Metallurgical Quarterly》1998,36(2):256-257
The paper deals with the in vitro assessment of endothelial cell (EC) phenotype covering an albumin- and chitosan-coated polyester fabric and shows that resting ECs express a pro-coagulant phenotype by releasing a high von Willebrand factor level and expressing low thrombomodulin surface activity, despite maintaining an adequate response to stimulating agents. 相似文献
110.
The putative E1 of hepatitis C virus (HCV) was expressed in Escherichia coli using a glutathione-S-transferase (GST) fusion protein system. The full length E1 protein is difficult to express. A series of E1 DNA fragments was generated and used for expression vector construction. Fusion proteins containing the E1 C-terminal region could not be expressed. When this region was truncated, the fusion proteins were synthesized to high levels. The possibility of this C-terminal region hampering the production of fusion protein was further explored. A construct with this segment directly fused to the C-terminus of GST indeed generated no detectable recombinant protein. According to the predicted structure of E1, this region may have membrane-associating properties. The expression results suggest a general approach to facilitate the production of viral membrane proteins in prokaryotes. Furthermore, these recombinant E1 proteins generated as antigens were used for Western blotting with sera from HCV-infected individuals. It was found that E1 is antigenic during HCV natural infection. 相似文献