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D McBride

Publications and source records attributed to D McBride.

At least 19 recordsLinked to original sources
PubMed2001

Health of farmers in southland: an overview.

AIM: To describe the health of farmers in Southland. METHODS: Coss-sectional study of a random sample of farmers in Southland. RESULTS: 586 individuals were interviewed from 286 farms with a response rate of 65.4%. The prevalence of at least one injury in the last twelve months which prevented normal farm work was 17.1%. Low back pain was common with 54.6% reporting such an episode in the last twelve months. Noise-induced hearing loss was prevalent among men with 28.7% of those 45 years and over being affected. Levels of asthma appeared low with a point prevalence of 6.8%, with 4.6% on medication. There were 19.3% of male farmers who were obese. The prevalence of alcohol use disorder among men aged 15-24 years was 57.4%, and 39.0% among farm workers. Similarly, 32.0% of men in this age-group smoked, with 35.6% of farm workers being smokers. CONCLUSIONS: Farmers experienced high levels of injury, low back pain and noise-induced hearing loss. Community intervention programmes to prevent injury remain a priority for farmers, although lifestyle factors should also be addressed, particularly among farm workers.

Adolescent↗
PubMed2001

Dosage compensation in birds.

The Z and W sex chromosomes of birds have evolved independently from the mammalian X and Y chromosomes [1]. Unlike mammals, female birds are heterogametic (ZW), while males are homogametic (ZZ). Therefore male birds, like female mammals, carry a double dose of sex-linked genes relative to the other sex. Other animals with nonhomologous sex chromosomes possess "dosage compensation" systems to equalize the expression of sex-linked genes. Dosage compensation occurs in animals as diverse as mammals, insects, and nematodes, although the mechanisms involved differ profoundly [2]. In birds, however, it is widely accepted that dosage compensation does not occur [3-5], and the differential expression of Z-linked genes has been suggested to underlie the avian sex-determination mechanism [6]. Here we show equivalent expression of at least six of nine Z chromosome genes in male and female chick embryos by using real-time quantitative PCR [7]. Only the Z-linked ScII gene, whose ortholog in Caenorhabditis elegans plays a crucial role in dosage compensation [8], escapes compensation by this assay. Our results imply that the majority of Z-linked genes in the chicken are dosage compensated.

Aconitate Hydratase↗
PubMed2001

A test of the reliability and validity of the Multnomah Community Ability Scale.

Previous research shows that the Multnomah Community Ability Scale (MCAS) total score is reliable and has predictive validity. This study evaluates the MCAS total and sub-scale scores on a sample of 1,250 outpatient mental health clients in Washington State. The MCAS sub-scales are reliable, and there is evidence for their concurrent validity. However, the factor structure of the MCAS only partially replicated the hypothesized sub-scales, and the authors recommend that sub-scales as currently constructed not be used as performance indicators. If only the total MCAS is of interest to users, the authors recommend using the single-item SOFAS rather than the 17-item MCAS.

Adolescent↗
PubMed2001

Characteristics of the audiometric notch as a clinical sign of noise exposure.

This study investigated variability in audiometric notch recognition by asking three clinicians to identify notches in the audiograms of 634 noise-exposed employees. Agreement between the raters was assessed, and three notch characteristics, frequency, depth and shape (a wide or narrow notch), were investigated as recognition factors. The proportions of positive tests reported by each rater were 0.26, 0.49 and 0.68, respectively. The 'all rater' index of agreement was 0.45, and the range for pairwise comparisons was 0.14 to 0.52. With recognition factors, rater 1 was most strongly influenced by depth, rater 2 by shape and rater 3 by a possible combination of criteria. To reduce variability we suggest that narrow notches should be at least 15 dB in depth, and that broad notches should have a depth of 20 dB, with a recovery of at least 10 dB at the high end. Care should also be taken to elicit a sufficient history of noise exposure, and ensure that there are no other explanations for the notch.

Audiometry↗
PubMed2001

Sexing chick embryos: a rapid and simple protocol.

1. Analysis of gene expression in the developing chick gonads requires the collection of male and female tissues from embryos between 3.5 d and 8.5 d of development. However, male and female chick embryos are indistinguishable by morphological examination before d 7.5 of development. 2. Sex identification of earlier embryos is only possible by molecular methods, which at present are laborious and time consuming. 3. We have devised a PCR-based sexing protocol which combines both sex specific and control reactions in a single tube assay. The assay is rapid and effective over a wide range of DNA concentrations and is tolerant of poor quality DNA. 4. Procedures are described for identifying the sex of individual embryos using either tissue samples or a small number of cells recovered from amniotic fluid.

Amniotic Fluid↗
PubMed2001

The effects of age and sex on susceptibility to motion sickness.

BACKGROUND: The present investigation is concerned with the role of sex, age and experience in determining motion sickness susceptibility. HYPOTHESIS: Motion sickness susceptibility varies with sex and age, and may be related to the level of physical activity sustained by the individual. METHODS: Three surveys were conducted. The first included school age children (9-18 yr) and addressed motion experience and motion sickness on 13 forms of transport. The second questionnaire sought to determine whether these sex differences could be understood in terms of differential involvement in various forms of physical activity. The third survey addressed the role of age and sex effects in a college age population. RESULTS: The first study revealed significantly greater motion sickness for female as compared with male subjects on devices with which both groups were equivalent in terms of exposure history. The second study showed little relation between an individual's level of physical activity and susceptibility to motion sickness. The results of the third study were in essential agreement with the first survey and revealed no significant interactions between age and sex, suggesting that sex differences remain stable across this age range. CONCLUSION: Our conclusions regarding these surveys are that sex differences in motion sickness do not vary significantly with age and cannot be accounted for by differences in exposure to motion or physical activity. There was also little evidence for the notion that men are more reticent to report motion sickness.

Adolescent↗
PubMed2000

Gene expression changes during murine postnatal brain development.

BACKGROUND: For most vertebrate organs and tissues, the majority of development occurs during embryogenesis, and postnatal changes are primarily concerned with growth. The central nervous system is unusual in that a considerable amount of morphological development, cell differentiation and acquisition of function, takes place during postnatal development. As yet, the molecular mechanisms underlying these complex developmental processes are not well understood. In order to identify markers for these developmental processes, we have analyzed the expression profiles, during postnatal murine brain development, of approximately 25,000 transcripts. This analysis, performed at day 1, day 10, day 20 and day 42 of postnatal development, identified a large number of developmentally regulated genes which we have assigned into three broad expression categories. RESULTS: Expression levels at four timepoints during postnatal murine brain development were established for approximately 25,000 gene transcripts. Approximately 1% of the genes examined displayed a developmentally regulated pattern of expression and we provide all the necessary information required to easily obtain molecular markers for a subset of these developmentally regulated transcripts. Of this subset, 61 showed increasing expression during development, 61 showed decreasing expression during development, and 9 exhibited a peak of expression during this period. CONCLUSIONS: A small percentage of the genes expressed in the postnatal developing brain show changes in expression level during the newborn to adult phase of development. It is likely that these developmentally regulated transcripts represent molecular markers for the complex developmental process occurring in the postnatal brain.

Aging↗
PubMed2000

Reduction of noise-induced hearing loss using L-NAC and salicylate in the chinchilla.

The effects of a combination of two antioxidant compounds were studied in a chinchilla model of noise-induced hearing loss. After obtaining baseline hearing thresholds using inferior colliculus evoked potentials, chinchillas were exposed for 6 h to octave band noise centered at 4 kHz (105 dB SPL). Post-noise thresholds were obtained 1 h after the noise exposure, and then animals received either saline or salicylate and N-L-acetylcysteine combination. Another group received antioxidant treatment 1 h prior to noise. Hearing was tested at 1, 2 and 3 weeks post-noise. Subsequently, the cochleae were harvested, and cytocochleograms were prepared. There was a 20-40 dB SPL threshold shift at 3 weeks for tested controls. Permanent threshold shifts (PTS) were significantly reduced (P<0.05) to approximately 10 dB for the pre-treatment group at week 3. The PTS for the post-treatment group at week 3 was similar to the pre-treatment group at 1 and 2 kHz (0-10 dB) but was intermediate between the control and pre-treatment groups at 4 and 8 kHz (23 dB). Animals pre-treated with antioxidant had a significant reduction in hair cell loss but those post-treated with antioxidant had no protection from hair cell loss. These findings demonstrate the feasibility of reduction of noise-induced hearing loss using clinically available antioxidant compounds.

Acetylcysteine↗
PubMed2000

Managing risk.

Explore the source record for details and available documents.

Humans↗
PubMed1999

Detection and typing of human papillomavirus DNA in paired urine and cervical scrapes.

The prevalence of human papillomavirus (HPV) in paired cervical scrape and urine specimens from 144 women attending a clinic for genitourinary medicine was determined by polymerase chain reaction (PCR) and nested PCR, using degenerate and general primer pairs localized within the L1 region. HPV typing was by restriction fragment length polymorphism (RFLP), type-specific PCR (HPV 6, 11, 16, 18, 33), and partial DNA sequencing of PCR products. HPV DNA was detected in 114 (84%) women. HPV DNA was detected in the specimens of 58 patients after amplification with MY09/MY11 primers and in a further 54 patients after nested PCR with the GP5+/GP6+ primers. A total of 106/136 (78%) of women had HPV DNA positive cervical scrapes and 89 (65%) had HPV DNA positive urine specimens. Both the urine and cervical specimens of 81 women were positive. In 25 women HPV DNA was detected in the cervical specimen only, and in 8 women HPV DNA was detected in the urine specimens only. A total of 108 specimens from 75 patients were typed. For 33 patients HPV typing was achieved in both the cervical and the urine specimens and 19 women had identical types in paired specimens. Multiple HPV infections could be detected in 15 (20%) of 75 women where either the cervical and urine specimen or both of the specimens could be typed. More then one HPV type was found in 8 specimens and from multiple sites (cervix and urinary tract) in the same patients on 7 occasions. The results of this study indicate that the detection of HPVs in the urogenital tract can be maximised through the testing of both cervical scrapes and urine specimens in conjunction with the use of a nested PCR to increase the sensitivity of HPV DNA detection. Also, urine cannot be a direct substitute for a cervical scrape as different HPV types are often detected in the urine compared with those detected in the cervix.

Adolescent↗
PubMed1999

Clinical validity of a self-test fructosamine in outpatient diabetic management.

BACKGROUND: Measurement of glycated hemoglobin and hemoglobin A1c (HbA1c) is now well established as the best means of measuring overall glucose control in managing diabetes. Other glycated serum protein assays reflecting recent glycemic control, e.g., glycated albumin and glycated protein (fructosamine), have also been validated in clinical studies. Regardless of the method, the expense and inconvenience of laboratory testing of blood samples may contribute to the well-documented underutilization of clinical glycated protein assessment. Accordingly, a rapid, inexpensive fingerstick test of fructosamine has been developed. This study cross-sectionally and prospectively assesses the clinical validity of fingerstick fructosamine versus laboratory determination. METHODS: Fifty-one subjects (18 control, 33 with diabetes) participated in a cross-sectional study and 20 subjects with type 2 diabetes participated in a prospective, 6-week study with clinical intervention consisting of glipizide gits or metformin in mono- and combination therapy. Subjects had weekly laboratory determination of serum fructosamine, glycated hemoglobin, and fasting glucose; fingerstick fructosamine was obtained at each clinic visit. RESULTS: Fingerstick fructosamine was shown to correlate highly to laboratory fructosamine (r = 0.80, p < 0.001) and glycated hemoglobin (r = 0.81, p < 0.001). In the clinical intervention study subjects, significant decreases in fasting glucose (p < 0.001), laboratory fructosamine (p < 0.001), and fingerstick fructosamine (p < 0.001) were noted compared to baseline. The subject's self-test fingerstick fructosamine mirrored laboratory testing of fructosamine in detection of changes in clinical glucose control. CONCLUSIONS: This study demonstrates that fingerstick fructosamine correlates well to laboratory assessment of fructosamine and glycated hemoglobin. The patient self-test fructosamine provides the same clinical information as laboratory assessment.

Adult↗
PubMed1998

Elimination of false positives generated through PCR re-amplification of differential display cDNA.

Differential display (DD) is a powerful molecular tool that allows the identification and subsequent isolation of transcripts differentially expressed between biological samples, for example, between undifferentiated and differentiated cells, between different tissues or in one tissue at different stages of development. However, significantly high rates of apparent false positives have been reported using this technique. We suggest that the vast majority of false positives do not represent the originally selected transcript, but instead result from the re-amplification of cDNA species that co-migrate with the cDNA of interest in DD gels. Here we describe the use of a procedure to resolve co-migrating cDNAs and to purify the candidate of interest before cloning. The use of this modified technique resolves downstream problems encountered during DD experiments.

Animals↗
PubMed1998

Knowledge of tuberculosis in high-risk populations: survey of inner city minorities.

SETTING: Educational programs targeted toward individuals at risk for tuberculosis are needed. As an initial step in developing future programs, the present study was designed to determine the baseline knowledge about tuberculosis in at-risk individuals. METHODS: Face-to-face surveys were conducted with 505 minority subjects in the Kansas City Metropolitan area; health care providers were excluded. Thirty-six queries directed toward self-perceived and actual tuberculosis knowledge were asked. Data were tabulated and per cent correct response was determined. RESULTS: Completed surveys were available from 505 subjects: 342 females and 163 males. Most (97%) of the subjects were African Americans, with 57% between the ages of 21-40. Over two-thirds were high school graduates, and 77% reported an estimated total household annual income of <$20000. Self-perceived knowledge about tuberculosis was rated as 'little' or 'nothing' by 60% of respondents. The overall correct response score was 61%, with 55% correct response to queries related to etiology, 53% for identification of high-risk populations, 57% for possible routes of transmission, 89% for symptoms, and 49% for treatment. Males, those with annual incomes >$20000, and individuals 51-70 years old had the highest scores. CONCLUSIONS: In this high-risk inner-city population surveyed, knowledge deficits in the etiology, transmission, and treatment of tuberculosis were identified.

Adolescent↗
PubMed1997

World War I origins of the syphilis epidemic among 20th century black Americans: a biohistorical analysis.

Syphilis outbreaks and differentials have been an ongoing issue in modern preventive medicine and public health. Since the early 20th Century, a variety of approaches has been employed to explain demographic and temporal variations in the prevalence of syphilis in the U.S. Public health experts and physicians have tended to rely on case-by-case approaches to explain group-specific patterns. This study, however, shows that population-level disease dynamics cannot be ascertained from these individual-level studies. We offer a biohistorical methodology to study syphilis prevalence differentials in U.S. populations. Using historical health data, this study suggests that the social disruption brought on by World War I was the critical and unique environmental condition which ignited an epidemic of syphilis among black Americans. By establishing this beginning point for the epidemic, this study further shows the persistence of the epidemic for the next 40 years and its decline. This biohistorical methodology could be applied to the analysis of STD epidemics in other populations and regions experiencing mass exposure events.

Black or African American↗