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Biomedical subjects

C Douglas

Publications and source records attributed to C Douglas.

At least 55 records · Page 3Linked to original sources

Empirically selected instruments for measuring quality-of-life dimensions in culturally diverse populations.

We describe a process for developing and testing the cultural equivalence of quality-of-life (QOL) instruments that may be used across culturally diverse populations. QOL instruments dealing with satisfaction with various life domains, psychological distress, and physical health and functioning were reviewed by African-American and Hispanic community advisory boards, translated into Spanish and back-translated to ensure translation adequacy, administered to samples of 100 patients from each of the ethnic minority populations by indigenous nurse interviewers, and examined for psychometric adequacy. Ten QOL measures showed adequate reliability and validity for further use in the assessment of QOL with African-American and Hispanic patients. Three other measures failed to meet the defined standards. A dimension shown to be particularly difficult to address across culturally diverse groups is family functioning. Procedures for achieving cultural equivalence of QOL measures have been shown to be practical and productive. Measures are identified that may be used with some confidence to assess varied dimensions of QOL with culturally diverse groups.

Adult↗

Nursing practice related to peritoneal catheter exit site care and infections.

OBJECTIVE: The purpose of the study was to obtain information from nephrology nurses on existing policies and protocols related to peritoneal catheter exit site care and treatment of exit site infections. DESIGN: This was an explorative, descriptive study. SAMPLE/SETTING: Fifty-four nurses who attended the 1995 Consensus Conference on Peritoneal Dialysis at the 26th Annual American Nephrology Nurses' Association National Symposium completed a survey questionnaire on exit site care and management of exit site infections. METHODS: A survey was mailed to nephrology nurses preregistered to attend the 1995 ANNA Consensus Conference related to peritoneal dialysis at the 26th National Symposium. Surveys were also collected at the meeting. RESULTS: Hydrogen peroxide and povidone iodine are frequently used in the nursing care of both healing and chronic exit sites. Almost all of the dialysis units require patients to stabilize or secure the catheter. The majority of respondents had a standardized method of assessing exit sites. Risk factors for exit site infections are presented for both the immediate post-catheter insertion period and the well-healed exit site. There were many different combinations of cleansing agents used to treat inflamed and infected exit sites. CONCLUSIONS: Procedures for exit site care vary widely. Prospective, randomized studies of exit site care protocols and cleansing agents are necessary to determine the most effective procedures to promote healthy exit sites.

Catheters, Indwelling↗

Terminal illness: views of patients and their lay carers.

This paper examines the responses of 28 terminally ill patients and their lay carers to identical questions about the patients' experiences in the month prior to their admission to an inpatient hospice. No statistically significant differences were found between the reports of patients or carers regarding the patients' activities of daily living, their physical symptoms, or the evaluations of the care they received. Discrepancies between accounts were most likely to concern the presence or absence of psychological symptoms, the degree of distress caused to patients by their symptoms, and the main symptoms experienced by the patient on their admission to the hospice. It is suggested that the accounts of patients' experiences given by their carers can be used as a valid source of information.

Activities of Daily Living↗

cDNA cloning of human kidney pyruvate carboxylase.

cDNA clones covering a total of 4017 bp were isolated corresponding to the full length of the message for human pyruvate carboxylase. The coding sequence consisted of a stretch of 3534 bp flanked by a 5' untranslated sequence of 82 bp and a 3' untranslated region of 389 bp excluding the poly-A tail. The translated amino acid sequence of 1178 residues contained consensus sequences for the covalent attachment for biotin, the binding of ATP and the binding of the substrate, pyruvate.

Amino Acid Sequence↗

Increased antifungal activity of L-733,560, a water-soluble, semisynthetic pneumocandin, is due to enhanced inhibition of cell wall synthesis.

The pneumocandins are natural lipopeptide products of the echinocandin class which inhibit the synthesis of 1,3-beta-D-glucan in susceptible fungi. The lack of a corresponding pathway in mammalian hosts makes this mode of action an attractive one for treating systemic infections. Substitution by an aminoethyl ether at the hemiaminal and dehydration and reduction of the glutamine of pneumocandin B0 produced a semisynthetic compound (L-733,560) with intrinsic water solubility, significantly increased potency, and a broader antifungal spectrum. To evaluate the mechanism for the improved antifungal efficacy, we determined that L-733,560 was a more potent inhibitor of glucan synthase activity in vitro, did not affect the other membrane-bound enzymes tested, conferred susceptibility to lysis in the absence of osmotic support, and did not disrupt currents in liposomal bilayers or 86Rb+ fluxes from liposomes. In Aspergillus species L-733,560 also produced the same morphological alterations as pneumocandin B0. A stereoisomer of L-733,560 with poor antifungal activity was a weak inhibitor of glucan synthase. All of these results support the notion that the enhanced antifungal activity of L-733,560 is achieved by superior inhibition of glucan synthesis and not by nonspecific membrane effects or a second mode of action.

Animals↗

Morphological effects of lipopeptides against Aspergillus fumigatus correlate with activities against (1,3)-beta-D-glucan synthase.

The lipopeptide antifungal agents, echinocandins, papulacandins, and pneumocandins, kill Candida albicans by inhibiting glucan synthesis. For this fungus, there is a good correlation of in vitro enzyme inhibition with in vitro assays of MICs. Semisynthetic lipopeptides such as cilofungin, LY303366, L-693,989, and L-733,560 have activity in vivo against Aspergillus infections but appear to be inactive in broth dilution in vitro tests (MICs, > 128 micrograms/ml). To understand how compounds which lack activity in vitro can have good in vivo activity, we monitored the effect of pneumocandins on the morphology of Aspergillus fumigatus and A, flavus strains by light microscopy and electron microscopy and related the changes in growth to inhibition of glucan synthesis. Pneumocandin B0 caused profound changes in hyphal growth; light micrographs showed abnormally swollen germ tubes, highly branched hyphal tips, and many cells with distended balloon shapes. Aspergillus electron micrographs confirmed that lipopeptides produce changes in cell walls; drug-treated germlings showed very stubby growth with thick walls and a conspicuous dark outer layer which was much thicker in the subapical regions. The rest of the hyphal tip ultrastructure was unaffected by the drug, indicating considerable specificity for the primary target. The drug-induced growth alteration produced very compact clumps in broth dilution wells, making it possible to score the morphological effect macroscopically. The morphological changes could be assayed quantitatively by using conventional broth microdilution susceptibility assay conditions. We defined the endpoint as the lowest concentration required to produce the morphological effect and called it the minimum effective concentration to distinguish it from the no-growth endpoints used in MIC determinations. The minimum effective concentration assay was related to inhibition of glucan synthase activity in vitro and may provide a starting point for development of susceptibility testing methods for lipopeptides.

Amino Acid Sequence↗

Selection of a human chromosome 21 enriched YAC sub-library using a chromosome-specific composite probe.

The subdivision of total genomic human yeast artificial chromosome (YAC) libraries into specific chromosome clone collections will greatly facilitate the construction of an integrated genetic, physical and transcriptional map of the genome. We report the isolation of 388 YAC clones from a human library with an average insert size of 620 kilobases (kb) by the hybridization of a composite chromosome 21 probe to a high-density array of YAC clones. Roughly half of these clones hybridize to chromosome 21 by fluorescence in situ hybridization. These clones represent a twofold coverage of the chromosome. The technique offers the potential of sub-dividing whole genomic YAC libraries into their chromosomal elements to produce high-resolution tools for genome mapping.

Base Sequence↗

Mapping irradiation hybrids to cosmid and yeast artificial chromosome libraries by direct hybridization of Alu-PCR products.

A direct hybridization protocol is described for screening cosmid and yeast artificial chromosome libraries with pools of Alu-PCR products from somatic cell or irradiation hybrids. This method eliminates purification, cloning and analysis of each individual Alu-PCR product before library screening. A series of human X chromosome irradiation hybrids were mapped by this method, using a cosmid reference library for comparisons between overlapping hybrids to identify interesting clones for further analysis.

Base Sequence↗

Effects of chest physical therapy on lung function in children recovering from acute severe asthma.

The effects of chest physical therapy in acute severe asthma in children have been studied in 38 children aged 6 to 13 years in a randomized placebo controlled trial. The study began between 6 and 24 hours after admission to hospital; 19 children received chest physical therapy (PT) and 19 children received placebo visits. Each child had 4 treatments over 2 days which were preceded by nebulized salbutamol. Lung volumes and flow rates were measured in a body plethysmograph before salbutamol and before and after either PT or placebo on the first and fourth treatments. Throughout the study standard asthma drug therapy was given. In both groups characteristics such as sex, race, age, height, weight, severity, and baseline lung function were similar. Taking into account the baseline, lung function at the end of the study was similar in both groups. Three 12 year old children in the PT group showed improvements in flows above those seen in any children in the placebo group. We conclude that chest PT, when combined with asthma drug therapy, does not improve lung function in most children in this age group with acute severe asthma.

Adolescent↗

Housing environments and community adjustment of severely mentally ill persons.

This study examined relationships between the quality and appropriateness of housing environments and community adjustment of 729 deinstitutionalized severely mentally ill clients in a state-wide community support service program. Environmental measures included ratings of the physical condition of the client's residence, its adequacy for six key life activities, and the overall appropriateness of the residential setting for the client. Community adjustment measures included global level of functioning, degree of maladaptive behavior and client's perceived quality of life. Evidence is presented that quality and appropriateness of housing environments significantly affect aspects of client's community adjustment outcomes over a nine-month period.

Adult↗

Microwave: practical cost-effective method for sterilizing urinary catheters in the home.

We used a standard microwave oven to sterilize red rubber catheters used for intermittent self-catheterization. Catheters were incubated for sixty minutes in a suspension of microorganisms isolated from the urine of patients with urinary tract infections. For each trial, 6 catheters were removed from their respective suspensions, placed in separate plastic freezer bags, distributed evenly in a microwave oven (avoiding cold spots), and microwaved simultaneously for twelve minutes. A control catheter was not microwaved. Two strains of each microorganism were tested. The urinary isolates were Escherichia coli, Klebsiella sp., Proteus sp., Enterobacter sp., Pseudomonas sp., Streptococcus sp., Staphylococcus sp., and Candida sp. In each experiment, all 6 catheters were sterilized. Repeat sterilization in the microwave oven did not affect the integrity of the catheters or the plastic bags. A water heat sink of constant volume was employed. A home microwave oven may be used as a method to sterilize red rubber catheters for reuse with a recommended time of twelve minutes at full power. This technique makes aseptic intermittent self-catheterization a practical possibility.

Bacteriuria↗

Serological evidence of dengue fever among refugees, Hargeysa, Somalia.

Epidemics of a malaria-like illness affected several thousand residents of the Dam Camp, a refugee camp near Hargeysa in Somalia, during 1985, 1986, and 1987. The disease was characterized by fever, chills, sweats, headache, back and joint pains for as long as 10 days in some patients. Blood smears from acutely ill patients were negative for malaria. Of 28 acute and 10 convalescent sera tested by the indirect fluorescent antibody (IFA) and by the hemagglutination inhibition (HI) tests, all were negative for antibody to Rift Valley fever, Crimean-Congo hemorrhagic fever, Sindbis, Chikungunya, yellow fever, and Zika viruses. However, antibody reactive to dengue 2 virus was detected by the IFA test in 39% (15/38), and 11 of 29 (38%) of the same sera were antibody positive by the HI test. Also, IgG antibody reactive to dengue 2 was demonstrated in 60% (17/28) of the same sera by the enzyme immunoassay (EIA), and 14% (4/28) were positive for IgM antibody. Of ten patients for which acute and convalescent sera were available, two developed four fold or greater rises in antibody titer evidencing infection. These data suggested that dengue virus may have been the cause of the epidemic among the Dam Camp refugees.

Antibodies, Viral↗

Primary structures and catalytic properties of isoenzymes encoded by the two 4-coumarate: CoA ligase genes in parsley.

We have determined the primary structures of two 4-coumarate: CoA ligase (4CL) isoenzymes in parsley (Petroselinum crispum) by sequencing near full-length cDNAs corresponding to the two 4CL genes, Pc4CL-1 and Pc4CL-2, present in this plant. Comparison of the cDNA and genomic nucleotide sequences showed that each 4CL gene is organized in five exons separated by introns of varying lengths. The positions of introns are the same in both genes and 97-99% of the corresponding nucleotide sequences are identical. The two isoenzymes, which are nearly identical in their primary structures, were separated by ion-exchange chromatography, and were found to be indistinguishable with regard to substrate specificity. Assignment to Pc4CL-1 and Pc4CL-2 was achieved by comparison with catalytically active 4CL proteins, isolated from Escherichia coli cells which had been transformed with plasmids harboring the corresponding cDNAs.

Amino Acid Sequence↗

Structure and elicitor or u.v.-light-stimulated expression of two 4-coumarate:CoA ligase genes in parsley.

We have isolated genomic clones encoding 4-coumarate:CoA ligase (4CL), a key enzyme of general phenylpropanoid metabolism, and have analysed the structure and regulation of the genes contained on these clones. Restriction enzyme and sequence analysis indicated that two distinct 4CL genes, Pc4CL-1 and Pc4CL-2, are represented on the clones and that additional 4CL genes are not present in parsley. Two lines of evidence suggest that each gene is transcriptionally activated by both elicitor and u.v. irradiation: cDNA clones corresponding to each gene were found in cDNA libraries made with RNA from both elicitor-treated and u.v-irradiated cells, and run-off transcripts homologous to a Pc4CL-2-specific intron probe were induced by both treatments. This induction was about half of the induction measured using probes homologous to both genes. The transcription initiation sites of both genes were determined. Comparison of the nucleotide sequences of the two genes 5' to these sites showed that they are highly homologous for several hundred base pairs and that they contain features potentially involved in regulation by elicitor and u.v. irradiation.

Journal Article↗