952 resultados para Variational problems of Herglotz type


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A UV-induced mutation of the enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPD) was characterized in the CHO clone A24. The asymmetric 4-banded zymogram and an in vitro GAPD activity equal to that of wild type cells were not consistent with models of a mutant heterozygote producing equal amounts of wild type and either catalytically active or inactive mutant subunits that interacted randomly. Cumulative evidence indicated that the site of the mutation was the GAPD structural locus expressed in CHO wild type cells, and that the mutant allele coded for a subunit that differed from the wild type subunit in stability and kinetics. The evidence included the appearance of a fifth band, the putative mutant homotetramer, after addition of the substrate glyceraldehyde-3-phosphate (GAP) to the gel matrix; dilution experiments indicating stability differences between the subunits; experiments with subsaturating levels of GAP indicating differences in affinity for the substrate; GAPD zymograms of A24 x mouse hybrids that were consistent with the presence of two distinct A24 subunits; independent segregation of A24 wild type and mutant electrophoretic bands from the hybrids, which was inconsistent with models of mutation of a locus involved in posttranslational modification; the mapping of both wild type and mutant forms of GAPD to chromosome 8; and the failure to detect any evidence of posttranslational modification (of other A24 isozymes, or through mixing of homogenates of A24 and mouse).^ The extent of skewing of the zymogram toward the wild type band, and the unreduced in vitro activity were inconsistent with models based solely on differences in activity of the two subunits. Comparison of wild type homotetramer bands in wild type cells and A24 suggested the latter had a preponderance of wild type subunits over mutant subunits, and had more GAPD tetramers than did CHO controls.^ Two CHO linkages, GAPD-triose phosphate isomerase, and acid phosphatase 2-adenosine deaminase were reported provisionally, and several others were confirmed. ^

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The adenovirus type 5 E1A gene was originally developed as a gene therapy to inhibit tumorigenicity of HER-2-overexpressing cells by transcriptional downregulation of HER-2. Our goal is to improve the overall efficacy of E1A gene therapy. To achieve this goal, we have conducted two preclinical experiments. ^ First, we hypothesized that Bcl-2 overexpressing ovarian cancer is resistant to E1A gene therapy. This hypothesis is based on that the 19 kDa protein product of the adenoviral E1B gene which is homologous to Bcl-2 inhibits E1A-induced apoptosis. Treating high Bcl-2-xpressing cells with E1A in combination with an antisense oligonucleotide to Bcl-2 (Bcl-2-ASO) resulted in a significant decrease in cell viability due to an increased rate of apoptosis relative to cells treated with E1A alone. In an ovarian cancer xenograft model, mice implanted with low HER-2, high Bcl-2 cells, treated with E1A plus Bcl-2-ASO led to prolonged survival. Bcl-2 thus may serve as a predictive molecular marker enabling us to select patients with ovarian cancer who will benefit significantly from E1A gene therapy. ^ Second, we elucidated the molecular mechanism governing the anti-tumor effect of E1A in ovarian cancer to identify a more potent tumor suppressor gene. We identified PEA-15 (phospho-protein enriched in astrocytes) upregulated in E1A transfected low HER-2-expressing OVCAR-3 ovarian cancer cell, which showed decreased cell proliferation. PEA-15 moved ERK from the nucleus to the cytoplasm and inhibited ERK-dependent transcription and proliferation. Using small interfering RNA to knock down PEA-15 expression in OVCAR-3 cells made to constitutively express E1A resulted in accumulation of phosphoERK in the nucleus, an increase in Elk-1 activity, DNA synthesis, and anchorage-independent growth. PEA-15 also independently suppressed colony formation in some breast and ovarian cancer cell lines in which E1A is known to have anti-tumor activity. We conclude that the anti-tumor activity of E1A depends on PEA-15. ^ In summary, (1) Bcl-2 may serve as a predictive molecular marker of E1A gene therapy, allowing us to select patients and improve efficacy of E1A gene therapy. (2) PEA-15 was identified as a component of the molecular mechanism governing the anti-tumor activity of E1A in ovarian cancer, (3) PEA-15 may be developed as a novel therapeutic gene. ^

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Background. Diabetes places a significant burden on the health care system. Reduction in blood glucose levels (HbA1c) reduces the risk of complications; however, little is known about the impact of disease management programs on medical costs for patients with diabetes. In 2001, economic costs associated with diabetes totaled $100 billion, and indirect costs totaled $54 billion. ^ Objective. To compare outcomes of nurse case management by treatment algorithms with conventional primary care for glycemic control and cardiovascular risk factors in type 2 diabetic patients in a low-income Mexican American community-based setting, and to compare the cost effectiveness of the two programs. Patient compliance was also assessed. ^ Research design and methods. An observational group-comparison to evaluate a treatment intervention for type 2 diabetes management was implemented at three out-patient health facilities in San Antonio, Texas. All eligible type 2 diabetic patients attending the clinics during 1994–1996 became part of the study. Data were obtained from the study database, medical records, hospital accounting, and pharmacy cost lists, and entered into a computerized database. Three groups were compared: a Community Clinic Nurse Case Manager (CC-TA) following treatment algorithms, a University Clinic Nurse Case Manager (UC-TA) following treatment algorithms, and Primary Care Physicians (PCP) following conventional care practices at a Family Practice Clinic. The algorithms provided a disease management model specifically for hyperglycemia, dyslipidemia, hypertension, and microalbuminuria that progressively moved the patient toward ideal goals through adjustments in medication, self-monitoring of blood glucose, meal planning, and reinforcement of diet and exercise. Cost effectiveness of hemoglobin AI, final endpoints was compared. ^ Results. There were 358 patients analyzed: 106 patients in CC-TA, 170 patients in UC-TA, and 82 patients in PCP groups. Change in hemoglobin A1c (HbA1c) was the primary outcome measured. HbA1c results were presented at baseline, 6 and 12 months for CC-TA (10.4%, 7.1%, 7.3%), UC-TA (10.5%, 7.1%, 7.2%), and PCP (10.0%, 8.5%, 8.7%). Mean patient compliance was 81%. Levels of cost effectiveness were significantly different between clinics. ^ Conclusion. Nurse case management with treatment algorithms significantly improved glycemic control in patients with type 2 diabetes, and was more cost effective. ^

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This paper is a review of the socio-economic literature on consumption. Considering consumption as a social activity, it examines how consumption solves the problems of interest, knowledge, and identity. It also discusses the main themes and important contributions in each category and offers suggestions for further research.

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The variational calculation of the energy of the Hydrogen Molecular (H2+) Cation's LCAO-MO for the sigma and sigma* states as functions of the AO's screening constant and the internuclear distance is carried out explicitly in great detail.

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The pi and pi-star orbitals of the hydrogen molecular cation are obtained using Maple in the same manner as the sigma and sigma-star orbitals were obtained in paper-36.

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This study was a retrospective design and used secondary data from the National Child Abuse and Neglect Data System (NCANDS), provided by the National Data Archive on Child Abuse and Neglect Family Life Development Center administered by Cornell University. The dataset contained information for the year 2005 on children from birth to 18 years of age. Child abuse and neglect for disabled children, was evaluated in-depth in the present study. Descriptive and statistical analysis was performed using the children with and without disabilities. It was found that children with disabilities have a lower rate of substantiation that likely indicates the interference of reporting due to their handicap. The results of this research demonstrate the important need to teach professionals and laypersons alike on how to recognize and substantiate abuse among disabled children.^

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Objective: The study aimed to identify the risk factors involved in initiating thromboembolism (TE) in pancreatic cancer (PC) patients, with focus on ABO blood type. ^ Methods and Patients: There were 35.7% confirmed cases of TE and 64.3% cases remained free of TE (n=687). There were 12.7% only Pulmonary embolism (PE), 9% only Deep vein thrombosis (DVT), 53.5% only other sites, 3.3% combined PE and DVT, 8.6% combined PE and other sites, 9.8% combined DVT and other sites, and 3.3% all three combined cases. ^ Results: The risk factors for thrombosis identified by multivariate logistic regression were: history of previous anti-thrombotic treatment, tumor site in pancreatic body or tail, large tumor size, maximum glucose category more than 126 and 200 mg/dL. ^ The factors with worse overall survival by multivariate Cox regression and Kaplan Meier analyses were: locally advanced or metastatic stage, worsening performance status, high CA 19-9 levels, and HbA1C levels more than 6 %, at diagnosis. ^ There were 29.1% and 39.1% of the patients with thrombosis in the O and non-O blood type groups respectively. Both Non-O blood type (P=0.02) and the A, B and AB blood types (P= 0.007) were associated with thrombosis as compared to O type. The odds of thrombosis were nearly half in O blood type patients as compared to non-O blood type [OR-0.54 (95% C.I.- 0.37-0.79), P<0.001]. ^ Conclusion: A better understanding of the TE and PC relationship and involved risk factors may provide insights on tumor biology and patient response to prophylactic anticoagulation therapy.^