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81.
Immunoblotting was used to dissect the antibody responses in the sera of 50 patients with proven invasive aspergillosis, 28 patients with suspected invasive aspergillosis, 35 patients with allergic bronchopulmonary aspergillosis, and 10 patients with an aspergilloma. This demonstrated the immunodominance of antigenic bands at 88, 84, 51, and 40 kDa. Monoclonal antibodies against the heat shock protein 90 complexes of Candida albicans and the water mold Achlya ambisexualis identified these four antigenic bands as homologous proteins. Similar antigens have been described in humans, mice, Saccharomyces cerevisiae, chickens, and Drosophila species. The antibody against A. ambisexualis has previously been shown to cross-react with antigens belonging to the human heat shock protein 90 complex. Aspergillus heat shock protein 90 was extracted from the sera of patients with invasive aspergillosis by affinity chromatography. This was done with both a rabbit hyperimmune antiserum raised against an extract of Aspergillus fumigatus NCPF 2109 and a monoclonal antibody against the heat shock protein 90 of C. albicans. In vivo expression of the antigen was demonstrated in an aspergilloma surgically removed from a patient. The role of the antigen as an allergen in allergic bronchopulmonary aspergillosis is also discussed. 相似文献
82.
Edwin J. Matthews 《Methods in Cell Science》1986,10(3):157-164
Summary The BALB/c-3T3 cell transformation assay evaluates the morphologic transforming potential of test chemicals using cultured mammalian cells as targets. The assay is semiquantitative and employs a contact-inhibited clone of cells derived from the original BALB/c-3T3 mouse cell line. Transforming activity, or a focus, is recognized as a dense layer of morphologically altered cells superimposed on a monolayer of the normal cell phenotype. The induction of transforming activity in a standard assay has been reported to correlate well with the carcinogenicity of many test chemicals in rodent bioassay; however, the standard assay does not detect carcinogens of all chemical classes. This report describes an operational protocol for the standard BALB/c-3T3 cell transformation assay. In addition, it provides assay acceptance criteria and a discussion of a method to evaluate transforming activity data. 相似文献
83.
Kristin M. Mattocks A. Rani Elwy Elizabeth M. Yano Justin Giovannelli Michael Adelberg Michelle A. Mengeling Kristin J. Cunningham Kameron L. Matthews 《Health services research》2021,56(3):400
ObjectivesTo inform how the VA should develop and implement network adequacy standards, we convened an expert panel to discuss Community Care Network (CCN) adequacy and how VA might implement network adequacy standards for community care.Data Sources/Study settingData were generated from expert panel ratings and from an audio‐recorded expert panel meeting conducted in Arlington, Virginia, in October 2017.Study DesignWe used a modified Delphi panel process involving one round of expert panel ratings provided by nine experts in network adequacy standards. Expert panel members received a list of network adequacy standard measures used in commercial and government market and were provided a rating form listing a total of 11 measures and characteristics to rate.Data Collection MethodsItems on the rating form were individually discussed during an expert panel meeting between the nine expert panel members and VA Office of Community Care leaders. Attendees addressed discordant views and generated revised or new standards accordingly. Recorded audio data were transcribed to facilitate thematic analysis regarding opportunities and challenges with implementing network adequacy standards in VA Community Care.Principal FindingsThe five highest ranked standards were network directories for Veterans, regular reporting of network adequacy data to VA, maximum wait time/distance standards, minimum ratio of providers to enrolled population, and qualitative assessments of network adequacy. During the expert panel discussion with VA Community Care leaders, opportunities and challenges implementing network adequacy standards were highlighted.ConclusionsOur expert panel shed light on priorities for network adequacy to be implemented under CCN contracts, such as developing comprehensive provider directories for Veterans to use when selecting community providers. Remaining questions focus on whether the VA could reasonably develop and implement network adequacy standards given current Congressional restraints on VA reimbursement to community providers. 相似文献
84.
Marshburn PB Zhang J Bahrani-Mostafavi Z Matthews ML White J Hurst BS 《Molecular human reproduction》2005,11(11):809-815
Progesterone receptor (PR) variant mRNAs in human endometrium could encode proteins with the potential to alter progesterone action in states of normal and abnormal endometrial development. We have assessed the expression levels of mRNA for the wild-type PR and splice variants of PR mRNA lacking exon 4 (del-4 PR), exon 6 (del-6 PR), exons 4 and 6 (del-4&6 PR), and part of exon 4 (del-p4 PR) or part of exon 6 (del-p6 PR) in the human endometrium throughout menstrual cycle development. Eighty-eight endometrial specimens (47 proliferative, 41 secretory) were collected from patients undergoing hysterectomy for benign gynaecologic causes. Measurements by RT-PCR indicated that mRNAs for wild-type PR, and splice variants del-4 PR, del-6 PR, del-4&6 PR, del-p6 PR, and a novel del-p4 PR were detected in all endometrial specimens throughout the menstrual cycle. Higher levels of wild-type PR and all PR variant mRNAs were found in the early and mid-proliferative endometrial phases than in secretory endometrium. The relative expression of mRNA for all PR variants compared to wild-type PR mRNA, however, did not change through all stages of endometrial development. We, therefore, found no evidence of differential co-expression of the PR variants compared with wild-type PR during normal menstrual development. Future studies will determine if the expression profile of PR variant mRNAs will be different in the endometrium of patients with infertility, recurrent pregnancy loss, or endometrial adenocarcinoma. 相似文献
85.
Nadia Falah Alissa Terry Amna Umer Marlee Kastner Kathryn L. Oliverio Nicole Matthews Kimberly M. Kelly Yvonne Kellar-Guenther 《American journal of medical genetics. Part A》2023,191(4):1013-1019
Telegenetics has shifted some genetic testing performance to the patient's own home, with the patient collecting his/her own sample. Little is known regarding the rate of test completion of such home-based genetic testing. This study compared the completion rate of home-based genetic tests before and after a reminder system was implemented. In the pre-reminder group, we reviewed medical records for patients who were seen via telegenetics and agreed to complete genetic testing using an at-home test kit. In the reminder group, a prospective analysis of the genetic test completion rate was performed taking a clinical quality improvement approach where three reminders were provided for patients who had not submitted their at-home genetic testing. Our study included 94 patients' records: 46 pre-reminders and 48 reminders. The lab received 24 patient samples (52.2%) in the pre-reminder group. In the reminder group, 30 patients returned their kits (62.5%). Despite a higher percentage of patients completing their test in the reminder group, there was no statistically significant difference between the pre-reminder and reminder groups. The rate of test completion in our pilot test was statistically similar between the two groups, but the reminder group was trending toward a higher percent of completion which may be clinically meaningful. 相似文献
86.
87.
Dr. B. D. Keavney C. R. K. Dudley I. M. Stratton R. R. Holman D. R. Matthews P. J. Ratcliffe R. C. Turner 《Diabetologia》1995,38(8):948-952
Summary The deletion allele of the insertion/deletion polymorphism of the angiotensin-converting enzyme gene has been suggested to be an independent risk factor for myocardial infarction, particularly in subjects judged to be low-risk by the criteria of lipid status and body mass index. In a prospective, matched case-control study, we have investigated the role of this polymorphism as a risk factor for myocardial infarction in 173 newly-diagnosed British Caucasian non-insulin-dependent diabetic subjects taken from the United Kingdom Prospective Diabetes Study who subsequently developed myocardial infarction and 297 control subjects from the same study population matched for known cardiovascular risk factors including age at diagnosis of diabetes, gender, blood pressure, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride and smoking habit. A trend towards increased risk conferred by homozygosity for the deletion allele was observed in cases (odds ratio 1.63, p=0.09). When the population was stratified according to the matched risk factors, the deletion allele was associated with myocardial infarction in those with low plasma low-density lipoprotein cholesterol (odds ratio 3.67, p=0.002), or low triglyceride (odds ratio 3.14, p=0.005). The strongest association of the deletion allele with myocardial infarction was observed in subjects with both low low-density lipoprotein cholesterol and low triglyceride levels (odds ratio 9.0, p<0.001). These results show that the deletion allele is a risk factor for myocardial infarction in non-insulin-dependent diabetic patients who have a favourable lipid profile.Abbreviations ACE
angiotensin-converting enzyme
- MI
myocardial infarction
- I/D polymorphism
insertion/deletion polymorphism
- I allele
insertion allele
- D allele
deletion allele
- DD genotype
homozygosity for the deletion allele
- UKPDS
United Kingdom Prospective Diabetes Study 相似文献
88.
Michael J. Millward David R. Newell Kally Yuen Jane P. Matthews Kathryn Balmanno Christopher J. Charlton Lindsey Gumbrell Michael J. Lind Fiona Chapman Madeleine Proctor Dorothy Simmonds Brian M. J. Cantwell A. Hilary Calvert 《Cancer chemotherapy and pharmacology》1995,37(1-2):161-167
The pharmacokinetics and pharmacodynamics of prolonged oral etoposide chemotherapy were investigated in 15 women with metastatic breast cancer who received oral etoposide 100 mg as a single daily dose for up to 15 days. There was considerable interpatient variability in the day 1 pharmacokinetic parameters: area under the plasma concentration time curve (AUC) (0–24 h) 1.95±0.87 mg/ml per min (mean ± SD), apparent oral clearance 60.9±21.7 ml/min per 1.73 m2, peak plasma concentration 5.6±2.5 g/ml, time to peak concentration 73±35 min and half-life 220±83 min. However, intrapatient variability in systemic exposure to etoposide was much less with repeated doses. The intrapatient coefficient of variation (CV) of AUC for day 8 relative to day 1 was 20% and for day 15 relative to day 1 was 15%, compared to the day 1 interpatient CV of 45%. Neutropenia was the principal toxicity. Day 1 pharmacokinetic parameters were related to the percentage decrease in absolute neutrophil count using the sigmoidal Emax equation. A good fit was found between day 1 AUC and neutrophil toxicity (R
2=0.77). All patients who had a day 1 AUC>2.0 mg/ml per min had WHO grade III or IV neutropenia. The predictive performance of the models for neutrophil toxicity was better for AUC (percentage mean predictive error 5%, percentage root mean square error 18.1%) than apparent oral clearance, peak plasma concentration, or daily dose (mg/m2). A limited sampling strategy was developed to predict AUC using a linear regression model incorporating a patient effect. Data sets were divided into training and test sets. The AUC could be estimated using a model utilizing plasma etoposide concentration at only two time points, 4 h and 6 h after oral dosing (R
2=98.9%). The equation AUCpr=–0.376+0.631×C4h+0.336×C6h was validated on the test set with a relative mean predictive error of –0.88% and relative root mean square error of 6.4%. These results suggest monitoring of AUC to predict subsequent myelosuppression as a strategy for future trials with oral etoposide.Division of Haematology and Medical Oncology, Peter MacCallum Cancer Institute, Locked Bag 1, A'Beckett St, Melbourne 3000, Australia 相似文献
89.
90.
K M Ratheiser G R Pesola R G Campbell D E Matthews 《JPEN. Journal of parenteral and enteral nutrition》1999,23(5):279-287
BACKGROUND: Infusion of epinephrine decreases plasma amino acid concentrations. However, the mechanism by which this decrement occurs is not well characterized. METHODS: Epinephrine was infused (40 ng/kg/min) for 2 hours into eight normal healthy adults. The essential amino acid tracers L-[1-(13)C]leucine and L-[phenyl-2H5]phenylalanine were infused before and during the epinephrine infusion and blood samples obtained to determine amino acid rates of appearance and disappearance from the time course of change in amino acid concentration and tracer enrichments. RESULTS: Epinephrine infusion decreased plasma leucine and phenylalanine concentrations over a period of 30 to 90 minutes after the start of the epinephrine infusion. Epinephrine infusion induced an immediate decrement in tracer enrichments. These changes defined sharp increases in both rate of appearance and rate of disappearance. By 30 minutes of epinephrine infusion, the rate of amino acid appearance from proteolysis had returned to baseline, but the rate of amino acid disappearance remained elevated for 90 minutes before returning to baseline. It was the protracted increase in amino acid disappearance that was responsible for the lowering of plasma amino acid concentrations. After this acute response, rates of amino acid appearance and disappearance returned to normal whereas plasma amino acid levels remained suppressed. CONCLUSIONS: Epinephrine transiently affects both rates of amino acid appearance and disappearance, with the net effect being increased in amino acid disappearance. However, epinephrine lowers amino acid concentrations beyond the period that it affects kinetics. These results suggest that the effect of epinephrine on amino acid metabolism is not detrimental and that epinephrine allows amino acid metabolism to proceed normally but at lower concentrations of amino acids. 相似文献