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Colvin M, Gumede L, Grimwade K, Maher D, Wilkinson D. Contribution of traditional healers to a rural tuberculosis control programme in Hlabisa, South Africa. Int J Tuberc Lung Dis 2003; 7:S86-91. [PMID: 12971659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
SETTING The rural health district of Hlabisa, KwaZulu-Natal, South Africa. OBJECTIVES To assess the acceptability and effectiveness of traditional healers as supervisors of tuberculosis (TB) treatment in an existing directly observed treatment, short-course (DOTS) programme. DESIGN An observational study comparing treatment outcomes among new TB patients in the three intervention sub-districts offered the additional option of traditional healers for directly observed treatment (DOT) supervision with those in the remainder of the district offered the standard range of options for DOT supervision (health facility, community health worker and lay persons). A comparison was also made of treatment outcomes between different options for DOT supervision. RESULTS A total of 3461 TB patients were registered in Hlabisa District from April 1999 to December 2000, of whom 2823 were discharged from hospital to the ambulatory DOT programme. Treatment outcomes were known for 1816 patients in Hlabisa District (275 patients in the intervention area and 1541 patients in the control area). There was no significant difference (P < 0.5) in treatment outcome in the intervention and control areas (77% vs. 75%). Among 275 patients with known outcomes in the intervention area, 48 patients were supervised by traditional healers and 227 patients supervised by people other than traditional healers. Treatment completion was not significantly higher among patients supervised by traditional healers than among patients supervised by other categories of DOT supervisor (88% vs. 75%, P = 0.3841). Interviews with 41 of 51 traditional healer patients who had completed treatment revealed high levels of satisfaction with the care received. CONCLUSIONS Traditional healers make an effective contribution to TB programme performance in this pilot scheme in Hlabisa district. Further evaluation will be necessary as this approach is scaled up.
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Abstract
In a prospective study, 60% of admissions to an academic hospital were infected with HIV. HIV infected children were younger, less likely to have been referred, more likely to have pneumonia and candidiasis, and had more health service attendances. This impact may be alleviated by appropriate primary and secondary level health care.
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Takebe N, Zhao SC, Adhikari D, Mineishi S, Sadelain M, Hilton J, Colvin M, Banerjee D, Bertino JR. Generation of dual resistance to 4-hydroperoxycyclophosphamide and methotrexate by retroviral transfer of the human aldehyde dehydrogenase class 1 gene and a mutated dihydrofolate reductase gene. Mol Ther 2001; 3:88-96. [PMID: 11162315 DOI: 10.1006/mthe.2000.0236] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The genetic transfer of drug resistance to hematopoietic cells is an attractive approach to overcoming myelosuppression caused by high-dose chemotherapy. Because cyclophosphamide (CTX) and methotrexate (MTX) are commonly used non-cross-resistant drugs, generation of dual drug resistance in hematopoietic cells that allows dose intensification may increase anti-tumor effects and circumvent the emergence of drug-resistant tumors. We constructed a retroviral vector containing both a human cytosolic ALDH-1 cDNA and a human doubly mutated DHFR cDNA (Phe22/Ser31; termed F/S in the description of constructs) to generate increased resistance to both CTX and MTX. Infection of NIH3T3 cells resulted in increased resistance to both 4-hydroperoxycyclophosphamide (4HC) (1.9 +/- 0.1-fold) and MTX (73 +/- 2.8-fold). Transduced human CD34(+) enriched hematopoietic progenitor cells were also resistant to both 4HC and MTX by CFU-GM readout. Lethally irradiated mice transplanted with SFG-ALDH-IRES-F/S or mock-transduced bone marrow cells were treated with high-dose pulse CTX or high-dose CTX/MTX. Animals receiving marrow not transduced with ALDH-1 or mutated DHFR cDNA died from CTX or CTX/MTX toxicity, whereas mice transduced with ALDH-1 and mutated DHFR cDNA-containing marrow were able to tolerate the same doses of CTX or CTX/MTX treatment posttransplant. These data taken together indicate that ALDH-1 overexpression and mutant DHFR increased both 4HC and MTX resistance in vitro and in the in vivo mouse model. This construct may be useful for protecting patients from high-dose CTX- and MTX-induced myelosuppression.
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Harsh GR, Deisboeck TS, Louis DN, Hilton J, Colvin M, Silver JS, Qureshi NH, Kracher J, Finkelstein D, Chiocca EA, Hochberg FH. Thymidine kinase activation of ganciclovir in recurrent malignant gliomas: a gene-marking and neuropathological study. J Neurosurg 2000; 92:804-11. [PMID: 10794295 DOI: 10.3171/jns.2000.92.5.0804] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The gene therapy paradigm of intratumoral activation of ganciclovir (GCV) following transduction of tumor cells by retroviral vectors bearing the thymidine kinase (tk) gene has produced dramatic remissions of malignant gliomas in animal models. In human trials, although the technique has been deemed safe, little antitumor effect has been demonstrated. To evaluate the basis of this inefficacy in human gliomas, the authors conducted a gene-marking trial involving neuropathological and biochemical studies of treated tumor specimens. METHODS Five patients with malignant recurrent gliomas underwent stereotactic biopsy sampling and intratumoral implantation procedures with three aliquots of 10(6) vector-producing cells (VPCs) in columns. After 5 days, the tumor was resected and the tumor bed reimplanted with VPCs, and a course of GCV was given. Patients received clinical and radiological follow up for 6 months. Tumor specimens were analyzed neuropathologically and for tk gene expression by anti-TK immunohistochemistry and TK enzymatic activity. Four patients tolerated the treatment well but experienced tumor progression. The other developed an abscess after the second operation and died. Increased TK enzymatic activity was demonstrated in the one tumor specimen analyzed. Immunohistochemical evidence of tk gene expression was limited to VPCs. Transduction of tumor cells was not seen. Viable tumor cells were seen near VPCs containing TK. The lymphocytic immune response was mild. CONCLUSIONS Except for the risk of infection inherent in reoperation, this tk-GCV paradigm was both feasible and safe. Pathological studies indicated that limited dissemination of VPCs and vector from the infusion site and failure to transduce tumor cells with the tk gene are major barriers to efficacy.
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Colvin M, Sharp B. Sexually transmitted infections and HIV in a rural community in the Lesotho highlands. Sex Transm Infect 2000; 76:39-42. [PMID: 10817067 PMCID: PMC1760578 DOI: 10.1136/sti.76.1.39] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVES To conduct a knowledge, attitude, and practice (KAP) study and to determine the prevalence of sexually transmitted diseases (STDs), including HIV, in a community residing in remote, rural Lesotho. METHODS In 1995 a cross sectional, community based epidemiological study was conducted on a population of 7500 people living in 89 villages. A total of 29 villages were randomly selected and a systematic sample of houses within villages was obtained. Questionnaires were administered to subjects after written consent was obtained. Determination of N gonococcus and C trachomatis infection was done on urine using ligase chain reaction (LCR) technology. Using blood specimens, syphilis was diagnosed by RPR and TPHA tests and HIV by a single ELISA and confirmed with a western blot. RESULTS Questionnaires were administered to 277 women, 100 men, and 149 youths (12-15 years). Chlamydia was diagnosed in 28.4% of adults, gonorrhoea in 5.9%, syphilis in 11.3%, and HIV infection in 6.3%. All cases of HIV occurred along the main road (p = 0.001) and 72% of individuals with gonorrhoea were co-infected with chlamydia (p = 0.0001). 11.6% of women and 38.0% of men had had sex with a non-regular partner in the past 3 months and none had used condoms. CONCLUSION A high prevalence of STDs and HIV infection was found in a population characterised by low levels of knowledge about STD/HIV, high risk sexual behaviour, and evidence of inappropriate health seeking behaviour for STDs.
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Myers JE, Nell V, Colvin M, Rees D, Thompson ML. Neuropsychological function in solvent-exposed South African paint makers. J Occup Environ Med 1999; 41:1011-8. [PMID: 10570508 DOI: 10.1097/00043764-199911000-00014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Neuropsychological and neurological function were investigated in 228 organic solvent exposed paint manufacturing workers in two factories. Solvent exposure was expressed as both American Conference of Governmental Industrial Hygienists 1990 Threshold Limit Value equivalents and total hydrocarbon parts per million. The World Health Organization (WHO) neurobehavioral core test battery, the Neurobehavioural Evaluation System--2 (NES-2), and the UNISA Neuropsychological Assessment Procedure (UNAP) were used to measure outcomes, and a Vibratron II was used to measure peripheral vibration sensation. Exposures were generally below the Threshold Limit Value, and no exposure effect was found. Possible explanations for this finding are discussed, including low exposure, exposure, and outcome misclassification, together with inappropriateness, nonvalidity, and relative insensitivity of neuropsychological tests. Only age predicted Vibratron score. Some tests were clearly inappropriate for use in developing countries. Neuropsychological tests were sensitive to educational level, age, alcohol consumption, and cultural indicators. The WHO tests in particular showed good construct validity for neuropsychological functions and should be more formally validated for use in developing countries. Nevertheless, a major problem of cultural dependence is evident for all neuropsychological tests used in this study, and methods for bypassing this problem in less developed settings are discussed.
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Forsyth JS, Varma S, Colvin M. A randomised controlled study of the effect of long chain polyunsaturated fatty acid supplementation on stool hardness during formula feeding. Arch Dis Child 1999; 81:253-6. [PMID: 10451400 PMCID: PMC1718074 DOI: 10.1136/adc.81.3.253] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND The passage of hard stools is significantly more common in formula fed infants than breast fed infants and this might be the result of differences in fat absorption between breast and formula fed infants. Experimental studies indicate that long chain polyunsaturated fatty acids (LCPUFAs) might influence fat hydrolysis and absorption. AIM To investigate the relation of LCPUFA supplementation to stool frequency and consistency during the first 4 months of life. DESIGN Double blind, randomised, controlled study of 88 healthy infants. RESULTS 1905 stools (858 from LCPUFA supplemented infants, 1047 non-supplemented infants) were examined. The mean (SEM) number of stools passed for each three day study period was significantly less in the LCPUFA group (5.5 (0.3) v 6.2 (0.2); p < 0.05). In both groups, there was a significant reduction in the number of stools passed with age (p < 0.001). During the first 3 months, the mean (SEM) percentage of hard stools passed by infants in the LCPUFA supplemented group was 7.7 (2.1) compared with 19.2 (2.8) for unsupplemented infants (p = 0.001). CONCLUSION The prevalence of hard stools is significantly reduced in infants fed a formula that is supplemented with LCPUFAs.
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Colvin M. Should AIDS be notifiable? S Afr Med J 1999; 89:147-8. [PMID: 10191866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
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Wilkinson D, Abdool Karim SS, Harrison A, Lurie M, Colvin M, Connolly C, Sturm AW. Unrecognized sexually transmitted infections in rural South African women: a hidden epidemic. Bull World Health Organ 1999; 77:22-8. [PMID: 10063657 PMCID: PMC2557569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
Sexually transmitted infections (STIs) are of major public health concern in developing countries, not least because they facilitate transmission of human immunodeficiency virus (HIV). The present article presents estimates of the prevalence, on any given day, of STIs among women in rural South Africa and the proportion who are asymptomatic, symptomatic but not seeking care, and symptomatic and seeking care. The following data sources from Hlabisa district were used: clinical surveillance for STI syndromes treated in health facilities, microbiological studies among women attending antenatal and family planning clinics, and a community survey. Population census provided denominator data. Adequacy of drug treatment was determined through quality of care surveys. Of 55,974 women aged 15-49 years, a total of 13,943 (24.9%) were infected on any given day with at least one of Trichomonas vaginalis, Neisseria gonorrhoeae, Chlamydia trachomatis, or Treponema pallidum. Of the women investigated, 6697 (48%) were asymptomatic, 6994 (50%) were symptomatic but not seeking care, 238 (1.7%) were symptomatic and would seek care, and 14 (0.3%) were seeking care on that day. Only 9 of the 14 women (65%) were adequately treated. STIs remained untreated because either women were asymptomatic or the symptoms were not recognized and acted upon. Improved case management alone is therefore unlikely to have a major public health impact. Improving partner treatment and women's awareness of symptoms is essential, while the potential of mass STI treatment needs to be explored.
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Colvin M, Dalvie A, Myers JE, Macun IA, Sharp B. Health and safety in the Lesotho Highlands Dam and Tunnel Construction Program. INTERNATIONAL JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HEALTH 1998; 4:231-5. [PMID: 9876631 DOI: 10.1179/oeh.1998.4.4.231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
To review health and safety practices and to determine the occupational health status of dam workers in the Lesotho Highlands, a health and safety audit and a health study of 258 workers was undertaken. The workers were administered respiratory health questionnaires and underwent chest x-rays and lung function and audiometric testing. The audit revealed a low level of awareness of health and safety issues at all levels of management and a lack of occupational medicine and industrial hygiene systems. Noise-induced hearing loss occurred among 92% of the study subjects. Among the 158 dam construction workers, 5.4% had pneumoconiosis. With poorly developed laws and regulatory bodies, unsophisticated trade unions, and little client supervision, health and safety had a low priority in this construction project. Recommendations are made that are pertinent to health and safety management where international companies are operating in developing countries.
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Willatts P, Forsyth JS, DiModugno MK, Varma S, Colvin M. Influence of long-chain polyunsaturated fatty acids on infant cognitive function. Lipids 1998; 33:973-80. [PMID: 9832076 DOI: 10.1007/s11745-998-0294-7] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Long-chain polyunsaturated fatty acids (LCPUFA) are important for normal visual and cortical development. In a previous study of the effects of LCPUFA on cognitive function of term infants at the age of 3 mon, we indicated that infants with evidence of reduced growth parameters at birth and impaired attention control as manifested by a late peak fixation during infant habituation assessment may benefit from LCPUFA supplementation. The aim of this prospective study was to determine whether LCPUFA supplementation and late peak fixation are related to means-end problem-solving ability in these same infants at the age of 9 mon. Term infants (58) were randomized to one of two formulas containing either LCPUFA or no LCPUFA and completed 4 mon of feeding with their formula. Cognitive function was assessed at 3 mon of age by measures of infant habituation. Infants (20 LCPUFA and 20 no-LCPUFA) completed the problem-solving assessment at 9 mon. The no-LCPUFA group had lower scores on both measures of intention and number of solutions, but neither of these differences was significant. Analysis of covariance for the effects of group and peak fixation, covaried with gestation and birth weight, showed that the number of solutions was significantly reduced in the late peak-fixation infants receiving no LCPUFA (P<0.02). Intention scores tended to be reduced in this group (P<0.06). The late peak-fixation infants who received LCPUFA had solution and intention scores similar to early peak-fixation infants receiving LCPUFA or no LCPUFA. These findings suggest that in term infants who have reduced growth parameters at birth and who show evidence of impaired attention control, information processing and problem-solving ability in infancy may be enhanced by LCPUFA supplementation.
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Colvin M, Abdool Karim SS, Connolly C, Hoosen AA, Ntuli N. HIV infection and asymptomatic sexually transmitted infections in a rural South African community. Int J STD AIDS 1998; 9:548-50. [PMID: 9764941 DOI: 10.1258/0956462981922683] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The objective was to determine the prevalence of HIV and other sexually transmitted infections (STIs) in a rural community. A population-based survey of adults in 110 homesteads was conducted in 1995. A questionnaire on demographics, sexual practices and history of STDs was administered. Neisseria gonorrhoeae and Chlamydia trachomatis infections were detected using ligase chain reaction (LCR) assay of urine. The seroprevalence of syphilis rapid plasma reagin (RPR) and Treponema pallidum haemagglutination assay (TPHA) and HIV infection (ELISA) was determined. Among 259 subjects the prevalence of HIV was 10.5%, N. gonorrhoeae 4.5%, C. trachomatis 6.1% and active syphilis 8.8%. All infections were asymptomatic. Forty per cent of sexually active men had more than one concurrent sexual partner. Only 14% of subjects had ever used condoms. The STI epidemic is being promoted by high levels of asymptomatic infections, high partner concurrency and low condom use.
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Colvin M, Mullick S, Kleinschmidt I. HIV surveillance in South Africa. S Afr Med J 1998; 88:1046. [PMID: 9798484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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Willatts P, Forsyth JS, DiModugno MK, Varma S, Colvin M. Effect of long-chain polyunsaturated fatty acids in infant formula on problem solving at 10 months of age. Lancet 1998; 352:688-91. [PMID: 9728984 DOI: 10.1016/s0140-6736(97)11374-5] [Citation(s) in RCA: 322] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Long-chain polyunsaturated fatty acids (LCPUFA) are important for normal visual and brain development. Although present in human milk, LCPUFA have until recently been absent from artificial formulas, and infants may have limited ability to synthesise LCPUFA. To determine the clinical significance of this relative deficiency of LCPUFA, we undertook a randomised trial of the relation between LCPUFA supplementation and infant cognitive behaviour. METHODS 44 term infants had been randomised to a formula supplemented with LCPUFA (21) or not supplemented with LCPUFA (23), which they had taken from birth to age 4 months. Infant cognitive behaviour was assessed at 10 months of age by a means-end problem-solving test--the intentional execution of a sequence of steps to achieve a goal. The problem required three intermediate steps to achieve the final goal, uncovering and retrieving a hidden toy. FINDINGS Infants who received LCPUFA-supplemented formula had significantly more intentional solutions than infants who received the no-LCPUFA formula (median 2.0 vs 0, p=0.021). Intention scores (median 14.0 vs 11.5 [maximum 18]) were also increased in this group (p=0.035). INTERPRETATION These findings suggest that term infants may benefit from LCPUFA supplementation, and that the effects persist beyond the period of supplementation. Since higher problem-solving scores in infancy are related to higher childhood IQ scores, supplementation with LCPUFA may be important for the development of childhood intelligence.
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Forsyth JS, Willatts P, DiModogno MK, Varma S, Colvin M. Do long-chain polyunsaturated fatty acids influence infant cognitive behaviour? Biochem Soc Trans 1998; 26:252-7. [PMID: 9649757 DOI: 10.1042/bst0260252] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Colvin M, Karim Abdool SS. HIV infection among patients with tuberculosis in KwaZulu/Natal, South Africa. Int J Tuberc Lung Dis 1998; 2:172. [PMID: 9562130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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Willatts P, Forsyth J, DiModugno M, Varma S, Colvin M. A randomised study of the effects of long-chain polyunsaturated fatty acids on infant habituation. Infant Behav Dev 1996. [DOI: 10.1016/s0163-6383(96)90877-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Davies GR, Wilkinson D, Colvin M. HIV and tuberculosis. S Afr Med J 1996; 86:91. [PMID: 8685792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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Colvin M, Abdool Karim SS, Wilkinson D. Migration and AIDS. Lancet 1995; 346:1303-4. [PMID: 7475752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Marsch GA, Ward RL, Colvin M, Turteltaub KW. Non-covalent DNA groove-binding by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine. Nucleic Acids Res 1994; 22:5408-15. [PMID: 7816632 PMCID: PMC332090 DOI: 10.1093/nar/22.24.5408] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The cooked meat mutagen 2-amino-1-methyl-6-phenyl-imidazo[4,5-b]pyridine (PhIP) is metabolized in vivo to electrophilic intermediates that covalently bind to DNA guanines. Here we address the mechanism of PhIP's non-covalent interaction with DNA by using spectroscopic and computational methodologies. NMR methodologies indicated that upon addition of DNA, PhIP aromatic protons underwent a small, 0.11-0.12 p.p.m. upfield shift. DNA phosphorus resonances of non-covalent PhIP-DNA complexes broadened and slightly shifted upfield, while DNA base imino proton resonances shifted slightly downfield relative to DNA alone. UV and fluorescence spectra of PhIP titrated with DNA showed no detectable shifting and hypochromism of absorbance or fluorescence bands. In the presence of DNA, PhIP fluorescence was efficiently quenched by acrylamide, but not by silver ion. Further, the NMR spectra suggest that PhIP is in fast exchange with the DNA, and is slightly specific for adenine-thymine (A-T) sequences. Finally, structural arguments based on quantum chemistry calculations suggested that PhIP and its metabolites are unlikely to intercalate into DNA. These data collectively indicate that PhIP non-covalently binds in a groove of DNA.
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Abstract
There has been some recent concern in Britain and North America that the increasing institutionalization of hospice care may compromise the movement's founding ideals. The threats posed by the encroachment of mainstream medicine and the medical technological imperative to treat, are also a source of concern to hospice administrators and staff. This study uses Australian data based on interviews with nurses and participant observation in an in-patient hospice unit and a community based hospice service to investigate whether the Good Death ideal, as central to the hospice philosophy, is compatible with the institutionalization of hospice care. The issues that arise, although interrelated are conceptualized as the following five challenges to hospice care: (1) encroachment of mainstream medicine and the medical technical imperative; (2) competing motivations; (3) delimitation of intellectual structures; (4) organizational maintenance; and (5) routinization of the Good Death. This conceptual framework is based on the way in which nurses and other health care professionals have used shared logic and strategies to negotiate the daily demands of their work and illustrates the tension that arises between the maintenance of the ideal and the maintenance of the organization.
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Nell V, Myers J, Colvin M, Rees D. Neuropsychological assessment of organic solvent effects in South Africa: test selection, adaptation, scoring, and validation issues. ENVIRONMENTAL RESEARCH 1993; 63:301-318. [PMID: 8243424 DOI: 10.1006/enrs.1993.1150] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The neurobehavioral effects of organic solvent exposure were assessed in 68 South African workers in a paint manufacturing plant in which the maximum current combined solvent level in workplace air was 0.72 of the Threshold Limit Value. A 17-test battery was assembled from the WHO-NCTB, NES 2, and the University of South Africa Neuropsychological Assessment Procedure. Extensive modifications were made to some tests in the battery, using a guided learning rationale derived from the cross-cultural literature. In light of test correlations with demographic variables (age, education, and alcohol consumption), the construct and likely predictive validity of the tests in the battery are reviewed, and promising procedures identified. Finally, it is noted that in developing countries, the results of neuropsychological tests that have been well standardized in the West may be misleading unless the underlying validity issues that arise when a test developed in one culture is applied to another have been addressed.
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Colvin M, Myers J, Nell V, Rees D, Cronje R. A cross-sectional survey of neurobehavioral effects of chronic solvent exposure on workers in a paint manufacturing plant. ENVIRONMENTAL RESEARCH 1993; 63:122-132. [PMID: 8404767 DOI: 10.1006/enrs.1993.1134] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Neurobehavioral impairments in 84 workers with long-term exposure to organic solvents in a paint manufacturing plant were examined cross sectionally. The World Health Organization (WHO) Neurobehavioral Core Test Battery, the NES-2 computerized battery, and four additional South African tests were used. Exposure to solvents was determined by using company industrial hygiene data as well as from an industrial hygiene survey of current total solvent levels in air. Indexes for cumulative exposure and average lifetime intensity of exposure were calculated for groups of homogeneously exposed workers in each department. Exposure levels were below the AGGIH threshold limit values. Multiple linear regression revealed that education level, age, and alcohol consumption were strong predictors for several neurobehavioral test scores. After adjusting for potential confounding from this source, average lifetime intensity of solvent exposure was the most significant predictor of the NES-2 Continuous performance test (measuring sustained visual attention) score of the WHO Digit span backward test score (measuring attention span and double tracking). Pursuit aiming (measuring fine visuomotor tracking speed) was significantly associated with the cumulative exposure index, possibly indicating early neurotoxic effects.
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Cromar BW, Colvin M, Casale TB. Validity of skin tests to cyclophosphamide and metabolites. J Allergy Clin Immunol 1991; 88:965-7. [PMID: 1744368 DOI: 10.1016/0091-6749(91)90256-n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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