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C Wilkes

Publications and source records attributed to C Wilkes.

12 recordsLinked to original sources
PubMed2001

Assessing exposure to disinfection by-products in women of reproductive age living in Corpus Christi, Texas, and Cobb county, Georgia: descriptive results and methods.

We conducted a field study in Corpus Christi, Texas, and Cobb County, Georgia, to evaluate exposure measures for disinfection by-products, with special emphasis on trihalomethanes (THMs). Participants were mothers living in either geographic area who had given birth to healthy infants from June 1998 through May 1999. We assessed exposure by sampling blood and water and obtaining information about water use habits and tap water characteristics. Two 10-mL whole blood samples were collected from each participant before and immediately after her shower. Levels of individual THM species (chloroform, bromodichloromethane, dibromochloromethane, and bromoform) were measured in whole blood [parts per trillion (pptr)] and in water samples (parts per billion). In the Corpus Christi water samples, brominated compounds accounted for 71% of the total THM concentration by weight; in Cobb County, chloroform accounted for 88%. Significant differences in blood THM levels were observed between study locations. For example, the median baseline blood level of bromoform was 0.3 pptr and 3.5 pptr for participants in Cobb County and Corpus Christi, respectively (p = 0.0001). Differences were most striking in blood obtained after showering. For bromoform, the median blood levels were 0.5 pptr and 17 pptr for participants in Cobb County and Corpus Christi, respectively (p = 0.0001). These results suggest that blood levels of THM species vary substantially across populations, depending on both water quality characteristics and water use activities. Such variation has important implications for epidemiologic studies of the potential health effects of disinfection by-products.

Activities of Daily Living↗
PubMed1998

Clinical supervision for specialist nurses.

The UKCC has stated that every practitioner should have access to clinical supervision. There is little literature on the supervision needs of specialist nurses. Choosing the appropriate model of supervision and establishing formal ground rules was essential to the success of the project.

Clinical Competence↗
PubMed1998

Pro-drinking messages and message environments for young adults: the case of alcohol industry advertising in African American, Latino, and Native American communities.

This paper examines targeted alcohol advertising in three ethnic communities: African Americans, Latinos, and Native Americans in the U.S. We focus on the appropriation of cultural systems and the reinvention of them as commodities to consumers. We outline the specific strategies used in each ethnic community. For African Americans, there is an emphasis on selling malt liquor to young adults through the use of "power" and gang-related images. For Latinos, there is an appropriation of historical and cultural symbols such as the national flags and maps of Mexico and Central America. Native Americans have coalesced to keep the image of a chief and warrior, Crazy Horse, from being used to market malt liquor. Each of the ethnic groups is engaged in action to prevent alcohol-related problems in their communities. Generating and implementing solutions is a universal social responsibility.

Adolescent↗
PubMed1997

Cloning and expression of a Xenopus laevis oocyte lectin and characterization of its mRNA levels during early development.

cDNA clones encoding a soluble, calcium-dependent, melibiose-binding lectin from Xenopus laevis oocytes have been isolated, characterized, and expressed in bacteria. This lectin has been shown by others to be localized in oocyte cortical granules where it ultimately is released and participates in the formation of the fertilization envelope. A lectin with similar specificity has been purified by others from blastula and immunolocalized to specific locations in developing embryos, which suggests it may also function after fertilization in regulating cell adhesion and migration. We have used melibiose affinity chromatography to isolate the oocyte lectin (monomer molecular masses of about 45 and 43 kDa) and shown that after exhaustive treatment with N-glycanase, only one major protein band at 35 kDa was observed, suggesting that a single polypeptide with variable N-linked glycosylation is expressed in the oocyte. After obtaining internal peptide sequences, a PCR-based cloning approach allowed the isolation of full length cDNAs from an ovary lambda gt11 library encoding a protein of 313 amino acids with three potential N-linked oligosaccharide sites. Although this lectin, termed XL35, requires calcium ions for oligosaccharide binding, its sequence does not contain the sequence motif defined for "C-type" lectins. A 6-Histagged from of the lectin was expressed in E. coli and purified on a Ni(2+)-NTA column from bacterial extracts. The recombinant lectin was active using an agglutination assay, and this activity was inhibitable by EDTA and melibiose, properties exhibited by the native lectin. Southern blot analysis revealed a single hybridizing band, arguing against the existence of a multigene family. Northern blot analysis demonstrated that the lectin mRNA is expressed in oocytes and remains at relatively high levels through late gastrulae, continuing until tadpole stages. The persistence of the lectin mRNA, coupled with results from earlier studies, strongly suggests that XL35 is zygotically expressed and functions during morphogenesis.

Amino Acid Sequence↗
PubMed1997

Localization by fluorescence in situ hybridization (FISH) of human mitochondrial polymerase gamma (POLG) to human chromosome band 15q24-->q26, and of mouse mitochondrial polymerase gamma (Polg) to mouse chromosome band 7E, with confirmation by direct sequence analysis of bacterial artificial chromosomes (BACs).

Cloned cDNAs for the human mitochondrial DNA polymerase gamma (POLG) were identified by homology with the yeast mitochondrial DNA polymerase catalytic subunit (MIP). Fluorescence in situ hybridization (FISH) of human and mouse bacterial artificial chromosomes (BACs), hybridized by radioactively labeled POLG cDNAs, mapped to human chromosome band 15q24-->q26, as well as to mouse chromosome band 7E. Direct sequencing of the BAC DNA without subcloning confirmed the presence of both human POLG and mouse mitochondrial DNA polymerase gamma (Polg) in the respective BACs.

Animals↗
PubMed1995

Glycosyltransferase assay system utilizing an acylated glycopeptide acceptor.

A glycosyltransferase assay system was devised utilizing as acceptor a purified glycopeptide which was acylated at its N-terminus using caprylic (C8) anhydride. The glycopeptide contained five amino acids and an N-linked biantennary oligosaccharide, and it was purified from a pronase digest of bovine fibrinogen. Desialylation and beta-galactosidase digestion conditions were developed to produce asialo- and asialo-agalacto glycopeptides. Using fatty acid anhydrides, N-acylation conditions for these glycopeptides were then optimized. The products formed when the appropriate acylated glycopeptide was incubated with either of two N-acetylglucosaminyltransferases and UDP-[3H]N-acetylglucosamine were easily separated from unused sugar nucleotide and breakdown products by exploiting the affinity of the radiolabeled acylated glycopeptide products for pellicular C18 cartridges. The products of the enzymatic reactions bound quantitatively to the cartridges and could be eluted in small amounts of methanol. The Km values for the unacylated and acylated glycopeptide acceptors were similar when measured using either N-acetylglucosaminyltransferase V or the N-acetylglycosaminyltransferase which transfers N-acetylglucosamine in beta(1,3) linkage to N-acetyllactosamine (or lactose). This assay system can be used to measure many glycosyltransferases and other enzymes which transfer to N-linked biantennary oligosaccharides and is applicable to additional glycosyltransferases that transfer to other oligosaccharides which can be prepared as glycopeptides.

Acylation↗
PubMed1986

Cumulative pregnancy rates for in vitro fertilization.

Data on 575 couples undergoing 1057 consecutive cycles of in vitro fertilization (IVF) were used to calculate cumulative pregnancy rates for repeated IVF cycles. Excluding preclinical abortions and couples in whom the male partner had poor semen parameters, calculated cumulative pregnancy rates for cycles 1 to 6 were 13.6%, 24.8%, 37.2%, 47.8%, 52.2%, and 59.6%, respectively. A parametric model used to fit these data yielded a strong correlation between observed and predicted pregnancy rates (r = 0.99, P less than 0.001). Predicted cumulative pregnancy rates after 9 and 12 cycles were 75% and 84%, respectively. Excluding preclinical abortions, the pregnancy rate per cycle was approximately constant, at approximately 15% over repeated cycles. As the cost of IVF declines and as treatment cycles become more easily tolerated, persistence in IVF can lead to successful pregnancy for a large proportion of couples.

Costs and Cost Analysis↗
PubMed1983

The importance of the follicular phase to success and failure in in vitro fertilization.

One hundred seventy-five cycles in patients with irreparable tubal disease were stimulated by human menopausal gonadotropin/human chorionic gonadotropin for the purpose of in vitro fertilization. As judged by the height of the peripheral estradiol response, the patients were classified as high, intermediate, or low responders. In addition, the estradiol pattern of the response was found to be separable into six categories. The pregnancy rate was found to be related to the height and to the pattern of peripheral response. The overall pregnancy rate in this consecutive series was 19% but varied according to the height and pattern of response from 40% to 0%.

Estradiol↗
PubMed1982

The program for in vitro fertilization at Norfolk.

Several aspects of the program of in vitro fertilization (IVF), or, as it is called in Norfolk, the program for the Vital Initiation of Pregnancy (VIP), have been or are in the process of publication. However, because there has been no overall account, it seems appropriate to give a brief report of a general nature covering the period from the beginning of the effort in late February 1980 through December 31, 1981. Although minor changes were constantly made in the protocol, there were two major revisions. Therefore, a discussion of the program during three distinct periods, i.e., 1980, 1981-Phase I, and 1981-Phase II, is necessary. During 1980 and 1981 all patients had either no fallopian tubes or irreparable tubes.

Adolescent↗
PubMed1976

Food poisoning.

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Bacillus cereus↗