21 resultados para Natural health product
Resumo:
The use of coal for fuel in place of oil and natural gas has been increasing in the United States. Typically, users store their reserves of coal outdoors in large piles and rainfall on the coal creates runoffs which may contain materials hazardous to the environment and the public's health. To study this hazard, rainfall on model coal piles was simulated, using deionized water and four coals of varying sulfur content. The simulated surface runoffs were collected during 9 rainfall simulations spaced 15 days apart. The runoffs were analyzed for 13 standard water quality parameters, extracted with organic solvents and then analyzed with capillary column GC/MS, and the extracts were tested for mutagenicity with the Ames Salmonella microsomal assay and for clastogenicity with Chinese hamster ovary cells.^ The runoffs from the high-sulfur coals and the lignite exhibited extremes of pH (acidity), specific conductance, chemical oxygen demand, and total suspended solids; the low-sulfur coal runoffs did not exhibit these extremes. Without treatment, effluents from these high-sulfur coals and lignite would not comply with federal water quality guidelines.^ Most extracts of the simulated surface runoffs contained at least 10 organic compounds including polycyclic aromatic hydrocarbons, their methyl and ethyl homologs, olefins, paraffins, and some terpenes. The concentrations of these compounds were generally less than 50 (mu)g/l in most extracts.^ Some of the extracts were weakly mutagenic and affected both a DNA-repair proficient and deficient Salmonella strain. The addition of S9 decreased the effect significantly. Extracts of runoffs from the low-sulfur coal were not mutagenic.^ All extracts were clastogenic. Extracts of runoffs from the high-sulfur coals were both clastogenic and cytotoxic; those from the low-sulfur coal and the lignite were less clastogenic and not cytotoxic. Clastogenicity occurred with and without S9 activation. Chromosomal lesions included gaps, breaks and exchanges. These data suggest a relationship between the sulfur content of a coal, its mutagenicity and also its clastogenicity.^ The runoffs from actual coal piles should be investigated for possible genotoxic effects in view of the data presented in this study.^
Resumo:
At issue is whether or not isolated DNA is patent eligible under the U.S. Patent Law and the implications of that determination on public health. The U.S. Patent and Trademark Office has issued patents on DNA since the 1980s, and scientists and researchers have proceeded under that milieu since that time. Today, genetic research and testing related to the human breast cancer genes BRCA1 and BRCA2 is conducted within the framework of seven patents that were issued to Myriad Genetics and the University of Utah Research Foundation between 1997 and 2000. In 2009, suit was filed on behalf of multiple researchers, professional associations and others to invalidate fifteen of the claims underlying those patents. The Court of Appeals for the Federal Circuit, which hears patent cases, has invalidated claims for analyzing and comparing isolated DNA but has upheld claims to isolated DNA. The specific issue of whether isolated DNA is patent eligible is now before the Supreme Court, which is expected to decide the case by year's end. In this work, a systematic review was performed to determine the effects of DNA patents on various stakeholders and, ultimately, on public health; and to provide a legal analysis of the patent eligibility of isolated DNA and the likely outcome of the Supreme Court's decision. ^ A literature review was conducted to: first, identify principle stakeholders with an interest in patent eligibility of the isolated DNA sequences BRCA1 and BRCA2; and second, determine the effect of the case on those stakeholders. Published reports that addressed gene patents, the Myriad litigation, and implications of gene patents on stakeholders were included. Next, an in-depth legal analysis of the patent eligibility of isolated DNA and methods for analyzing it was performed pursuant to accepted methods of legal research and analysis based on legal briefs, federal law and jurisprudence, scholarly works and standard practice legal analysis. ^ Biotechnology, biomedical and clinical research, access to health care, and personalized medicine were identified as the principle stakeholders and interests herein. Many experts believe that the patent eligibility of isolated DNA will not greatly affect the biotechnology industry insofar as genetic testing is concerned; unlike for therapeutics, genetic testing does not require tremendous resources or lead time. The actual impact on biomedical researchers is uncertain, with greater impact expected for researchers whose work is intended for commercial purposes (versus basic science). The impact on access to health care has been surprisingly difficult to assess; while invalidating gene patents might be expected to decrease the cost of genetic testing and improve access to more laboratories and physicians' offices that provide the test, a 2010 study on the actual impact was inconclusive. As for personalized medicine, many experts believe that the availability of personalized medicine is ultimately a public policy issue for Congress, not the courts. ^ Based on the legal analysis performed in this work, this writer believes the Supreme Court is likely to invalidate patents on isolated DNA whose sequences are found in nature, because these gene sequences are a basic tool of scientific and technologic work and patents on isolated DNA would unduly inhibit their future use. Patents on complementary DNA (cDNA) are expected to stand, however, based on the human intervention required to craft cDNA and the product's distinction from the DNA found in nature. ^ In the end, the solution as to how to address gene patents may lie not in jurisprudence but in a fundamental change in business practices to provide expanded licenses to better address the interests of the several stakeholders. ^
Resumo:
Mechanisms of multidrug resistance (MDR) were studied in two independent MDR sublines (AdR1.2 and SRA1.2) derived from the established human colon carcinoma cell line LoVo. AdR1.2 was developed by long-term continuous exposure of the cells to adriamycin (AdR) in stepwise increments of concentration, while SRA1.2 was selected by repetitive pulse treatments with AdR at a single concentration. In this dissertation, the hypothesis that the mechanism of drug resistance in SRA1.2 is different than that in AdR1.2 is tested. While SRA1.2 demonstrated similar biological characteristics when compared to the parental LoVo, AdR1.2 exhibited remarkable alterations in biological properties. The resistance phenotype of AdR1.2 was reversible when the cells were grown in the drug-free medium whereas SRA1.2 maintained its resistance for at least 10 months under similar conditions. Km and Vmax of carrier-mediated facilitated diffusion AdR transport were similar among the three lines. However, both resistant sublines exhibited an energy-dependent drug efflux. AdR1.2 appeared to possess an activated efflux pump, and a decreased nucleus-binding of AdR, whereas SRA1.2 showed merely a lower affinity in binding of AdR to the nuclei. Southern blot analysis showed no amplification of the MDR1 gene in either of the two resistant subclones. However, Western blot analysis using the C219 monoclonal antibody against P170 glycoprotein detected a Mr 150-kDa plasma protein (P150) in AdR1.2 but not in SRA1.2 or in the parental LoVo. In vitro phosphorylation studies revealed that P150 was a phosphoprotein; its phosphorylation was Mg$\sp{2+}$-dependent and could be enhanced by verapamil, an agent capable of increasing intracellular AdR accumulation in AdR1.2 cells. The phosphorylation studies also revealed elevated phosphorylation of a Mr 66-kDa plasma membrane protein that was detectable in the AdR1.2 revertant and in AdR1.2 when verapamil was present, suggesting that hyperphosphorylation of the Mr 66-kDa protein may be related to the reversal of MDR. SDS-PAGE of the plasma membrane protein demonstrated overproduction of a Mr 130-kDa, MDR-related protein in both the resistant sublines. The Mr 130-kDa, MDR-related protein in both the resistant sublines. The Mr 130-kDa protein was not immunoreactive with C219, but its absence in the AdR1.2 revertant and the parental LoVo suggests that it is an MDR-related plasma membrane protein. In conclusion, the results from this study support the author's hypothesis that the mechanisms responsible for "Acquired" and "Natural" MDR are not identical. ^
Resumo:
The purpose of this research was development of a method of estimating nutrient availability in populations as approximated by supermarket purchase records. Demographic information describing 12,516 panel households was obtained from a marketing and advertising program operated by H. E. Butt Grocery Company of San Antonio, Texas. A non-probability sample of 2,161 households meeting expenditure criteria was selected and all purchases of dairy products for this sample of households were organized into a database constructed to facilitate the retrieval, aggregation, and analysis of dairy product purchases and their nutrient contents. Two hypotheses were tested: (1) no difference would be found between Hispanic and non-Hispanic purchases of dairy product categories during the study period and (2) no difference would be found between Hispanic and non-Hispanic purchases of nutrients contained in those dairy products during the thirteen-week study period.^ Food purchase records were used to estimate nutrient exposure on a weekly, per capita basis for Hispanic and non-Hispanic households by linking some 40,000 dairy purchase Universal Product code (UPC) numbers with food composition values contained in USDA Handbook 8-1. Results of this study suggest Hispanic sample households consistently purchased fewer dairy products than did non-Hispanic sample households and consequently had fewer nutrients available from dairy purchases. While weekly expenditures for dairy products among the sample households remained relatively constant during the study period, shifts in the types of dairy products purchased were observed. The effect of ethnicity on dairy product and nutrient purchases was significant over the thirteen-week period. A database consisting of customer, household, and purchase information can be developed to successfully associate food item UPC numbers with a standard reference of food composition to estimate nutrient availability in a population over extended periods of time. ^
Resumo:
The non-Hodgkin's B cell lymphomas are a diverse group of neoplastic diseases. The incidence rate of the malignant tumors has been rising rapidly over the past twenty years in the United States and worldwide. The lack of insight to pathogenesis of the disease poses a significant problem in the early detection and effective treatment of the human malignancies. These studies attempted to investigate the molecular basis of pathogenesis of the human high grade B cell non-Hodgkin's lymphomas with a reverse genetic approach. The specific objective was to clone gene(s) which may play roles in development and progression of human high grade B cell non-Hodgkin's lymphomas.^ The messenger RNAs from two high grade B cell lymphoma lines, CJ and RR, were used for construction of cDNA libraries. Differential screening of the derived cDNA libraries yielded a 1.4 kb cDNA clone. The gene, designated as NHL-B1.4, was shown to be highly amplified and over-expressed in the high grade B cell lymphoma lines. It was not expressed in the peripheral blood lymphoid cells from normal donors. However, it was inducible in peripheral blood T lymphocytes by a T cell mitogen, PHA, but could not be activated in normal B cells by B cell mitogen PMA. Further molecular characterization revealed that the gene may have been rearranged in the RR and some other B cell lymphoma lines. The coding capacity of the cDNA has been confirmed by a rabbit reticulocyte lysate and wheat germ protein synthesis system. A recombinant protein with a molecular weight of approximate 30 kDa was visualized in autoradiogram. Polyclonal antisera have been generated by immunization of two rabbits with the NHL-B1.4 recombinant protein produced in the E. coli JM109. The derived antibody can recognize a natural protein with molecular weight of 49 kDa in cell lysate of activated peripheral T lymphocytes of normal donors and both the cell lysate and supernatant of RR B cell lymphoma lines. The possible biologic functions of the molecule has been tested preliminarily in a B lymphocyte proliferation assay. It was found that the Q-sepharose chromatograph purified supernatant of COS cell transfection could increase tritiated thymidine uptake by B lymphocytes but not by T lymphocytes. The B cell stimulatory activity of the supernatant of COS cell tranfection could be neutralized by the polyclonal antisera, indicating that the NHL-B1.4 gene product may be a molecule with BCGF-like activity.^ The expression profiles of NHL-B1.4 in normal and neoplastic lymphoid cells were consistent with the current B lymphocyte activation model and autocrine hypothesis of high grade B cell lymphomagenesis. These results suggested that the NHL-B1.4 cDNA may be a disease-related gene of human high grade B cell lymphomas, which may codes for a postulated B cell autocrine growth factor. ^
Resumo:
Elevated expression levels of the bcl-2 proto-oncogene have been correlated with the appearance of androgen independence in prostate cancer. Although bcl-2 was first cloned as the t (14:18) translocation breakpoint from human follicular B cell lymphoma, the mechanism of overexpression of bcl-2 is largely undefined for advanced prostate cancer, there being no gross alterations in the gene structure. We investigated the role of the product of the prostate apoptosis response gene-4 (Par-4) and the product of the Wilms' tumor 1 gene (WT1) in the regulation of Bcl-2 expression in prostate cancer cell lines. We observed growth arrest and apoptosis, upon decreasing Bcl-2 protein and transcript in the high Bcl-2 expressing, androgen-independent prostate cancer cell lines, by all trans-retinoic acid treatment but this did not occur in the androgen-dependent cell lines expressing low levels of Bcl-2. Changes in localization of Par-4, and an induction in the expression of WT1 protein accompanied the decrease in the Bcl-2 protein and transcript following all trans-retinoic acid treatment, in the androgen-independent prostate cancer cell line. In stable clones expressing ectopic Par-4 we observed decreased Bcl-2 protein and transcript. This was accompanied by an induction in WT1 expression. Finally, we detected Par-4 and WT1 proteins binding to a previously identified WT1 binding site on the bcl-2 promoter both in vitro and in vivo leading to a decrease in transcription from the bcl-2 promoter. We conclude that Par-4 regulates Bcl-2 through a WT1 binding site on the bcl-2 promoter. ^