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A Green

Publications and source records attributed to A Green.

At least 91 records · Page 5Linked to original sources
PubMed2001

Determination of plasma free carnitine by electrospray tandem mass spectrometry.

We have evaluated a tandem mass spectrometry method for determining free carnitine concentrations in plasma and have compared its performance with that of an existing radioenzymatic assay. In this method, plasma was mixed with an internal standard, carnitine-d3 (600 nmol/L), and butylated before analysis on a Quattro II tandem mass spectrometer. The detection limit of the tandem mass spectrometric (MS) method was 4 micromol/L and carryover between samples was 2.2%. Precision of the method was 1.6-5.4% between injections and 4.0-5.6% between samples. Between-batch precision was 10-13%. The method was linear up to a free carnitine concentration of 300 micromol/L and good agreement was found with the existing radioenzymatic assay. We conclude that the tandem MS method is a precise and robust method for the determination of free carnitine concentrations in plasma that overcomes the disadvantages of the radiochemical method.

Blood Chemical Analysis↗
PubMed2001

Review of the epidemiologic literature on EMF and Health.

Exposures to extremely low-frequency electric and magnetic fields (EMF) emanating from the generation, transmission, and use of electricity are a ubiquitous part of modern life. Concern about potential adverse health effects was initially brought to prominence by an epidemiologic report two decades ago from Denver on childhood cancer. We reviewed the now voluminous epidemiologic literature on EMF and risks of chronic disease and conclude the following: a) The quality of epidemiologic studies on this topic has improved over time and several of the recent studies on childhood leukemia and on cancer associated with occupational exposure are close to the limit of what can realistically be achieved in terms of size of study and methodological rigor. b) Exposure assessment is a particular difficulty of EMF epidemiology, in several respects: i) The exposure is imperceptible, ubiquitous, has multiple sources, and can vary greatly over time and short distances. ii) The exposure period of relevance is before the date at which measurements can realistically be obtained and of unknown duration and induction period. iii) The appropriate exposure metric is not known and there are no biological data from which to impute it. c) In the absence of experimental evidence and given the methodological uncertainties in the epidemiologic literature, there is no chronic disease for which an etiological relation to EMF can be regarded as established. d) There has been a large body of high quality data for childhood cancer, and also for adult leukemia and brain tumor in relation to occupational exposure. Among all the outcomes evaluated in epidemiologic studies of EMF, childhood leukemia in relation to postnatal exposures above 0.4 microT is the one for which there is most evidence of an association. The relative risk has been estimated at 2.0 (95% confidence limit: 1.27-3.13) in a large pooled analysis. This is unlikely to be due to chance but, may be, in part, due to bias. This is difficult to interpret in the absence of a known mechanism or reproducible experimental support. In the large pooled analysis only 0.8% of all children were exposed above 0.4 microT. Further studies need to be designed to test specific hypotheses such as aspects of selection bias or exposure. On the basis of epidemiologic findings, evidence shows an association of amyotrophic lateral sclerosis with occupational EMF exposure although confounding is a potential explanation. Breast cancer, cardiovascular disease, and suicide and depression remain unresolved.

Adolescent↗
PubMed2001

The epidemiology of childhood-onset type 1 diabetes mellitus in Romania. ONROCAD Study Group. National Romanian Organisation for the Care of Diabetic Children and Adolescents.

The ONROCAD Study group was established to provide descriptive epidemiological information on type 1 diabetes mellitus (DM) in Romania. Data on all new patients with type 1 DM with onset before age 15 years during the four-year period 1992-1995 in Romania were submitted from all members of the ONROCAD Study Group, representing all doctors and clinics that manage children with DM in Romania. Age- and sex-specific incidence rates were estimated, using available demographic data. A total of 706 new patients with type 1 DM and onset 0-14 years was registered. The overall completeness of ascertainment was estimated at 93.5%. For all Romania, the incidence of childhood-onset type 1 DM was estimated at 3.57/100,000/year. The incidence in the three regions was statistically significantly different (p = 0.002), with high rates in Transylvania and low rates in Muntenia. Girls had a significantly higher incidence than boys for each of the age groups 0-4, 5-9 and 10-14 years. Between these age groups, the incidence increased significantly with age. The incidence of childhood-onset type 1 DM is among the lowest recorded in Europe. Significant, but unexplained, geographical variation exists within Romania. Searches for factors to explain this heterogeneity may provide clues to the etiology of childhood-onset type 1 DM.

Adolescent↗
PubMed2001

Diffuse solar UV radiation and implications for preventing human eye damage.

Ocular UV exposure is a function of both the direct and diffuse components of solar radiation. Broadband global and diffuse UV measurements were made in the morning, noon and afternoon. Thirty sets of measurements were made in summer and 50 in each of the other seasons at each of the periods in full sun. Corresponding sets were made in the shade of Australian evergreen trees: 42 trees in summer and 50 in each of the other seasons. The percentage diffuse UV was higher for the shorter 320-400 nm range (UVB) than for 280-320 nm (UVA). The percentage diffuse UVB ranged from 23 to 59%, whereas the percentage diffuse UVA ranged from 17 to 31%. The percentage diffuse UV was lower at noon than in the morning and afternoon with the difference more pronounced for the UVB. The average percentage diffuse UVB over all the measurements in the tree shade for the morning, noon and afternoon was 62, 58 and 71%, respectively, and the average percentage diffuse UVA was 52, 51 and 59%, respectively.

Australia↗
PubMed2001

Photosensitization of the sunscreen octyl p-dimethylaminobenzoate by UVA in human melanocytes but not in keratinocytes.

Sunscreens penetrate human epidermis and modify the biology of proliferating cells. This study addressed the question whether the UV response of cultured human cells is affected by direct treatment with nontoxic levels of sunscreens. Cell survival following exposure to UVC or unfiltered UBV was not altered by preincubation with 25 micrograms/mL of octyl p-dimethylaminobenzoate (o-PABA), 2-ethylhexyl p-methoxycinnamate (EHMC) or oxybenzone. However, UVA or UVB filtered to reproduce the solar UV spectrum penetrating to the basal layer of the epidermis, highly sensitized cells to killing by o-PABA but not by its hydrolysis product, 4-dimethylaminobenzoic acid. Sensitization was found in all cell types tested, except normal keratinocytes, and could be prevented by certain antioxidants particularly pyruvate and the hydroxyl radical scavenger mannitol. o-PABA and EHMC applied without UV reduced the adherence of cells. The results indicate that sunscreens may increase cell mobility and the combination of o-PABA with solar UV may selectively damage melanocytes in the skin.

4-Aminobenzoic Acid↗
PubMed2001

Fecal shedding of Salmonella spp. by dairy cows on farm and at cull cow markets.

As part of a national study of the U.S. dairy cow population, fecal samples were collected from representative cows on 91 dairies and 97 cull dairy cow markets in 19 states. Salmonella spp. were recovered from 5.4% of milk cows, 18.1% of milk cows expected to be culled within 7 days, and 14.9% of culled dairy cows at markets. On a premise basis, Salmonella shedding in milk cows was detected on 21.1% of dairies and 66% of cull dairy cow markets. The percentage of herds with at least one cow with detectable Salmonella fecal shedding was higher during the sampling period from May through July, in herds with at least 100 milk cows, and in herds in the South region. The most common Salmonella serogroups isolated were E (30.8% of isolates) and C1 (28.6%); the most common serotypes isolated were Salmonella Montevideo (21.5% of isolates), Salmonella Cerro (13.3%), and Salmonella Kentucky (8.5%). Fecal shedding of Salmonella Typhimurium or Salmonella Typhimurium var. copenhagen was infrequent (2.8% of isolates). Most isolates (88.9%) were susceptible to all 17 antimicrobials evaluated; multiple resistance was an infrequent occurrence. This study provides information describing the distribution of Salmonella fecal shedding from dairy cows on farm and at markets and will serve as a baseline for future studies.

Animals↗
PubMed2001

The hepatocyte as a microbial product-responsive cell.

Much research has focused on the responses to microbial products of immune cells such as monocytes, macrophages, and neutrophils. Although the liver is a primary response organ in various infections, relatively little is known about the antimicrobial responses of its major cell type, the hepatocyte. It is now known that the recognition of bacteria occurs via cell-surface proteins that are members of the Toll-like receptor (TLR) family. In addition, lipopolysaccharide (LPS) is bound by circulating LPS-binding protein (LBP) and presented to cell-surface CD14, which in turn interacts with TLR and transduces an intracellular signal. We investigated the CD14 and TLR2 responses of whole liver and isolated hepatocytes, and demonstrated that these cells can be induced to express the molecules necessary for responses to both Gram-positive and Gram-negative bacteria. Our findings may have clinical implications for pathological states such as sepsis.

Acute-Phase Proteins↗
PubMed2000

Prognostic value of P53 nuclear accumulation and histopathologic features in T1 transitional cell carcinoma of the urinary bladder.

OBJECTIVES: To determine whether molecular and histopathologic tumor features can predict disease progression in Stage T1 transitional cell carcinoma of the bladder. METHODS: Tumor specimens from 43 patients were analyzed with respect to grade, presence of carcinoma in situ, invasion deep or superficial to the lamina propria's muscularis mucosa, p53 expression using DO-7 and PAb1801 antibodies, age, and sex. Flow cytometry was performed on 30 patients from whom there was adequate paraffin-embedded tissue to assess DNA ploidy. Seven patients underwent immediate cystectomy as primary treatment and 36 patients retained their bladders and were at risk of recurrence and progression. RESULTS: The median follow-up was 79 months. Disease recurred in 17 patients (47.2%) and progressed in 6 (16.7%). Only 3 patients (7.0%) died of bladder cancer. None of the parameters investigated was statistically significant in predicting recurrence, progression, or survival. Only carcinoma in situ approached statistical significance (P = 0.0593) as a predictor of progression. Early cystectomy did not have a significant effect on cancer-specific survival (P = 0.3603). The concordance rate between the two p53 antibodies was 88% (P <0.0001). CONCLUSIONS: Deep invasion of the lamina propria, p53 positive immunohistochemistry, high grade, and aneuploidy were not significant adverse prognostic factors for either disease progression or survival. Carcinoma in situ associated with Stage T1 transitional cell carcinoma may represent a biologically more aggressive cancer requiring early definitive therapy, but this hypothesis should be evaluated in prospective clinical studies.

Adult↗
PubMed2000

Insights from a large rural population laboratory. Health census '89 and '99.

PURPOSE: Data are limited on health status behaviors and use of health services for rural residents. Yet rural areas now have higher rates of chronic diseases, such as coronary heart disease, than urban areas.METHODS: A population laboratory (Health Census) was established in rural Central NY (Otsego County) to study these variables in this population. HC '89 was a door-to-door enumeration of all permanent households in the country. In 1989, 44,500 adults in 18,000 households provided data on individual health screenings, cancer and cardiovascular risk factors, health behaviors, chronic disease, access to care, preventive services use, health insurance and emergency department utilization. Data collection for HC '99 will identify 10-year trends; it also includes baseline data for children. Also, households in six surrounding rural counties (N = 10,000) were sampled; cost benefits of different survey methods were assessed. Questions about perceived health status, and special health and pediatric preventive care needs were included. After 10 years of social change, many limitations of traditional survey methods became apparent; much more varied and frequent types of follow-up were needed to achieve adequate response rates.RESULTS: The HC '89 final response rate was 86%. There were significant socioeconomic gradients in use of preventive services (blood pressure screening, rectal exams, mammograms and Pap smears). Adults without health insurance or Medicaid had much lower utilization rates of screening tests and higher rates of cigarette smoking and obesity. Several community intervention programs were implemented as a result of HC '89. HC '99 provides additional analyses to examine change in preventive service use, self-reported chronic disease, and health services use; it will likely verify the persistence of socioeconomic gradients. Response rates are similar to '89, but achieved only with more intensive reinforcement.CONCLUSIONS: HC '89 confirmed a lag in positive health indices in rural populations in Central NY. Both newer methodologies now needed and results of HC '99 will serve as guides for smaller rural counties to develop affordable local health surveys and plan intervention strategies.

Journal Article↗
PubMed2000

The effect of a zinc, cobalt and selenium soluble glass bolus on trace element status and semen quality of ram lambs.

Supplemental zinc and selenium were administered to ram lambs grazed on pastures that were not considered to be deficient in either element. The breeding season and polygamy of the ram mean that his requirements for semen production will be relatively large over a short breeding season and this may induce a localised deficiency of zinc and/or selenium, thus resulting in a decrease in semen quality and production.Thirty-three 8-month-old ram lambs were kept at grass and fed a supplement of barley and peas, with ad libitum access to grass silage when grazing became restricted. On day 0, the rams were allocated to two groups by restricted randomisation of live weight. One group each had a zinc, cobalt and selenium soluble glass bolus (Zincosel(R), Telsol) administered with the other group not receiving a bolus to act as a control. Blood samples were taken by jugular venipuncture at day 0 (prior to bolus administration) and at days 23, 44, 65 and 86. Blood samples were analysed for zinc status (plasma zinc concentration) and selenium status (erythrocyte glutathione peroxidase activity). Semen was collected once a week between days 44 and 86, by diversion during a natural mount. Semen quality was assessed by ejaculate volume, spermatocrit, sperm concentration, abnormal morphology, motility, percentage live (negrosin-eosin stain), membrane integrity (hypo-osmotic swelling test (HOS)) and seminal fluid glutathione peroxidase activity and zinc concentration. The bolused lambs had a significantly increased erythrocyte glutathione peroxidase activity (P<0.01) on all samplings after bolusing and had significant increases in motility, proportion of live sperm and proportion of intact membranes indicated by the HOS. The bolused ram lambs had an increased selenium status and apparent improvement in semen membrane quality.

Animals↗
PubMed2000

Fluorescence in situ hybridization detection of two telomeres on the short arm of a derived chromosome 16 in an infant with thrombocytopenia.

We report a case of severe thrombocytopenia with an abnormal bone marrow karyotype described by G-banding analysis as t(16;21)(p?13;q11). Using fluorescence in situ hybridization (FISH) analysis with whole chromosome paints, the chromosome rearrangement was shown to be more complex, with the additional cryptic involvement of the long arm of chromosome 3. The chromosome rearrangement involved the breakpoints 3q26, 16p13.3, and 21q11; this rearrangement has not been previously described. The size of genomic material translocated from the chromosome 16 homologue was too small to be detected by chromosome paint. A 16p-specific telomeric probe was hybridized to locate the translocated 16p material. The 16p telomeric unique sequence DNA was retained on the der(16) chromosome, indicating a more distal breakpoint. This study demonstrates that telomeric translocations can occur that would be undetected by telomeric-specific FISH probes.

Bone Marrow Cells↗
PubMed2000

[Hereditary hemorrhagic telangiectasia. A population-based study on prevalence and mortality among Danish HHT patients].

Hereditary haemorrhagic telangiectasia (HHT) is a dominantly inherited disease characterized by telangiectatic lesions. The disease manifestations are variable in severity. Early death due to complications has been described. We report an investigation of the prevalence and mortality of HHT in a Danish population, based on two cross-sectional surveys in combination with a long-term follow-up study. The prevalence of HHT in the county of Funen was 13.8 per 100,000 January 1. 1974 and 15.6 per 100,000 January 1. 1995. In the HHT group as a whole we found a slightly increased mortality, however among the HHT patients younger than 60 years at inclusion the mortality of HHT patients was twice the expected. The excess mortality was fully explained by severe HHT symptoms contributing to death. Future research should aim at identification of HHT patients at particular risk of developing severe complications.

Adult↗
PubMed2000

Case-control study in a subtropical Australian population to assess the relation between non-melanoma skin cancer and epidermodysplasia verruciformis human papillomavirus DNA in plucked eyebrow hairs. The Nambour Skin Cancer Prevention Study Group.

Epidermodysplasia verruciformis human papillomavirus (EV-HPV) DNA has been demonstrated in malignant and benign skin lesions and in hairs plucked from renal transplant recipients and immunocompetent patients. We investigated the association between EV-HPV DNA in hairs plucked from eyebrows and the occurrence of non-melanoma skin cancer (NMSC) in a community-based study. Within a cohort of residents of a Queensland township (Nambour), nested case-control studies of recently developed NMSC (64 cases), basal-cell carcinoma (BCC) (51 cases) and squamous-cell carcinoma (SCC) (25 cases) were conducted. EV-HPV DNA in hair and a small number of available tumour samples was detected using a nested PCR specific for EV-HPV types. EV-HPV DNA was detected in hairs from 94 of 143 individuals (66%), and 36 (39%) of the samples contained 2 or more different EV-HPV types. Only known or putatively new EV-HPV types were detectable after sequencing 93 samples. EV-HPV status agreed for 12 of 20 subjects who had both hair and skin tumour samples available. In 4 of 5 pairs of positive samples, the same EV-HPV type was found. There were non-significant negative associations between EV-HPV and NMSC (OR 0.77, 95% CI 0.34-1.8) and BCC (OR 0.58, 95% CI 0.23-1.5) but a non-significant positive association with SCC (OR 2.00, 95% CI 0.50-8.0).

Adult↗
PubMed2000

Longitudinal study of risk factors for coronary heart disease across the menopausal transition.

The patterns of change in blood lipids, diastolic blood pressure, body mass index, smoking and drinking behaviors, and exercise were examined in an ongoing longitudinal study from 1991 to 1995 of 150 middle-aged Melbourne, Australia, women as they passed through menopause. Changes in risk factors over time were examined with reference to time of the final menstrual period (FMP). Random effects models were fitted with adjustments for repeated measures and other covariates, including age. There were overall net increases between 3 years before and the 3 years after menopause of 0.25 mmol/liter for low density lipoprotein cholesterol, 0.05 mmol/liter for high density lipoprotein cholesterol (HDL cholesterol), 0.34 mmol/liter for triglycerides, 0.12 kg/m2 for body mass index, and 0.48 mmHg for diastolic pressure. The proportion of drinkers decreased by 13%, that of smokers increased by 17%, and that of women who exercised at least once a week increased by 6%. The only change dependent on the FMP was a significant decrease in HDL cholesterol (counterbalanced by a similar rise in HDL cholesterol in the year before the FMP), and the rate of decrease was maximal around 9 months after menses ceased, with an instantaneous estimate of slope of 0.55 mmol/liter per year.

Blood Pressure↗
PubMed2000

The intrapsychic and intersubjective in psychoanalysis.

Both the intrapsychic and the intersubjective take part in the analytic process. A pointless struggle for supremacy may await those who support either point of view exclusively. If the "objectal" perspective is well known, the "subjectal" one is less theoretically defined: it includes the series of the ego, the self, the subject, the I, etc. The drive is the matrix of the subject. An examination of the relationships between perception and representation raises the question of the connections between drive and object. The object is the revealer of the drive. A revision of Freud's theory must underline the role of the object, which is unduly neglected. The new paradigm should consider the indissociable couple, drive-object. The construction of the object leads retroactively to the hypothesis of the drive, which reciprocally constructs the object. The function of the similar other (autre semblable) is defined as a fundamental link (desire and identification). The intersubjective relationship connects two intrapsychic subjects. Force and meaning are intertwined and combine their effects. Psychic causality is at the crossroads of the biological (metabiological) and the cultural. This paper examines the transition from the first topographic model to the second.

Humans↗
PubMed2000

Oxygen tension in primary gynaecological tumours: the influence of carbon dioxide concentration.

BACKGROUND AND PURPOSE: To assess the effect of inhalation of various high oxygen content gases (HOCG) with different carbon dioxide concentrations on the tumour oxygen tension in patients with primary gynaecological malignancies. MATERIALS AND METHODS: Tumour oxygen tension was assessed on two protocols in those patients with locally advanced visible or palpable primary gynaecological malignancies. Patients were assessed initially while breathing room air (R/A). After 4 min of inhaling the first HOCG, a second assessment of the oxygen tension within the tumour was made. After a 10 min rest period while inhaling R/A, the second HOCG was administered for 4 min after which the third set of measurements were obtained. Protocol A involved assessing the tumour oxygen tension in 12 patients while breathing R/A, 100% oxygen (O(2)) and 5% carbogen (95% O(2), 5% CO(2)). For protocol B, tumour oxygen tension assessments of 13 patients while breathing R/A, 2.5% carbogen (97.5% O(2), 2.5% CO(2)), and 5% carbogen. Median pO(2) and percentage of values </=2.5 mmHg were assessed. RESULTS: Regarding protocol A, the median of the median pO(2) values increased from 5 mmHg when breathing R/A to 47 mmHg for 100% O(2) and to 105 mmHg for 5% carbogen inhalation. The median of the percentage of values </=2. 5 mmHg decreased: 17% for R/A vs. 16% for 100% O(2) (P=ns) vs. 0% for 5% carbogen (P=0.015). In protocol B, the median of the median pO(2) values increased from 3 mmHg when breathing R/A to 73 mmHg when inhaling 2.5% carbogen and to 72 mmHg for 5% carbogen inhalation. The median of the percentage of values </=2.5 mmHg decreased with both carbogen mixtures compared with room air: 42% for R/A vs. 0% for 2.5% carbogen (P=0.05) and 3% for 5% carbogen (P=0.015). No statistically significant difference in this parameter was found between the two carbogen concentrations. CONCLUSION: Oxygen tension as measured with an Eppendorf pO(2) histograph, increased with inhalation of the oxygen and carbon dioxide gas mixtures tested. While 100% oxygen inhalation increased the median pO(2) compared with R/A a significantly greater increase in oxygen tension was seen with inhalation of either carbogen gas mixture. Pure oxygen inhalation did not decrease the percentage of values </=2.5 mmHg whereas inhalation of either 2.5 and 5% carbogen gas resulted in a significant decrease in this parameter. Both carbogen concentrations appear equal at increasing the oxygen tension in primary gynaecological tumours as measured with the Eppendorf pO(2) histograph.

Administration, Inhalation↗
PubMed2000

Problems of quality designation in diffusely polluted urban streams - the case of Pymme's Brook, north London.

Downstream patterns in the biology and bacteriology of Pymme's Brook (north London) between 1985 and 1992, are compared with the local Environment Agency (EA, England and Wales) quality classification of the site, revealing a considerable discrepancy. Although downstream contaminant dispersal patterns showed that at low flow the brook was less successful in absorbing contaminants at polluted surface water outfall (PSWO) entry points than it was at high flow (supporting the low flow strategy of contemporary audit schedules), this effect was found to vary downstream in response to reoxygenation from less polluted outfalls. Additionally, temporal variations in suspended solids, Escherichia coli counts, sediment-bound and soluble pollutant concentrations at low flow, and during two sampled storms, revealed that significant pollutant transfer was concentrated in the 'first flush' of storm events. A downstream survey of sediment-bound lead (Pb) found that concentrations in the bed sediments, which were likely to be mobilised during a first flush, were significantly higher than in solution. So, a complex pattern of downstream contaminant dispersal emerges, which varies with differing antecedent conditions, and through storms. These results indicate that: (1) the new General Quality Assessments (GQA) audit schedule proposed by the EA for England and Wales remains inappropriate for diffusely polluted, urban environments, because it omits routine E. coli counts and sediment-bound heavy metals; and that (2) when audit is based on chemical determinants alone, the choice of site and timing of audit excessively influence quality designations. Pre-audit planning surveys and more reliable alternatives to the use of chemical audit for urban watercourses, are discussed as possible ways forward for the design of quality audit schedules. Implications for the monitoring schedules in operation in other EU countries and the USA are also considered.

Journal Article↗