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First Exposure (first + exposure)
Selected AbstractsFirst Exposure in Man: Toxicological ConsiderationsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2000Per Spindler Recommendations on the type and extent of preclinical safety studies that should be conducted prior to first dose in man have been developed by the International Conference on Harmonisation, and the European Committee for Proprietary Medicinal Products. These recommendations include studies designed to characterise local tolerance and general toxicity of the drug candidate as well as its genotoxic potential and ability to interfere with reproduction. For trials which can be categorised as low dose PK screening trials and trials with products where rodent and non-rodent (primarily dog) models do not show any biological response (e.g. some biotechnology-derived hormones and cytokines) other testing paradigms should be used. The present recommendations for preclinical testing have had an important impact on the documented impressive safety record of phase I clinical trials. In this spirit we extend our warmest and sincerest thanks to Professor Jens S. Schou for his long and deep engagement in European and International harmonisation of preclinical test recommendations. His efforts have had a substantial impact on the present testing recommendations, which are of obvious benefit to the safety of the patient. [source] The association of use of sunbeds with cutaneous malignant melanoma and other skin cancers: A systematic reviewINTERNATIONAL JOURNAL OF CANCER, Issue 5 2007Article first published online: 27 NOV 200 Abstract Exposure to solar ultraviolet (UV) radiation is a known cause of skin cancer. Sunbed use represents an increasingly frequent source of artificial UV exposure in light-skinned populations. To assess the available evidence of the association between sunbed use and cutaneous malignant melanoma (melanoma) and other skin cancers, a systematic review of the literature till March 2006 on epidemiological and biological studies on sunbed use was performed in Pubmed, ISI Web of Science, Embase, Pascal, Cochrane library, Lilacs and Medcarib. Search for keywords in the title and in the abstract was done systematically and supplemented by manual searches. Only case,control, cohort or cross-sectional studies were selected. Data were abstracted by means of a standardized data-collection protocol. Based on 19 informative studies, ever-use of sunbeds was positively associated with melanoma (summary relative risk, 1.15; 95% CI, 1.00,1.31), although there was no consistent evidence of a dose,response relationship. First exposure to sunbeds before 35 years of age significantly increased the risk of melanoma, based on 7 informative studies (summary relative risk, 1.75; 95% CI, 1.35,2.26). The summary relative risk of 3 studies of squamous cell carcinoma showed an increased risk. For basal cell carcinoma, the studies did not support an association. The evidence does not support a protective effect of the use of sunbeds against damage to the skin from subsequent sun exposure. Young adults should be discouraged from using indoor tanning equipment and restricted access to sunbeds by minors should be strongly considered. © 2006 Wiley-Liss, Inc. [source] Repeated exposures to gustatory stimuli produce habituation or positive contrast effects in perinatal ratsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2004G. Andrew Mickley Abstract Adult rats exhibit a decrease in consummatory responses following repeated presentations of a taste (habituation) and an increase in consummatory responses if they experience an upward shift in the magnitude or intensity of a gustatory stimulus (e.g., sucrose or saccharin). These responses do not represent a direct sensorimotor reaction to a gustatory cue, but rather reflect a change in responding based on the memory of a previous taste. Here, we sought to determine if fetal rats could (like adults) adjust their orofacial motor responses based on a memory of recent gustatory experience. Embryonic Day 18 (E18) or Day 19 (E19) rat fetuses received oral lavage with either 0.15 or 0.30% saccharin (SAC). Subsequently, observations of orofacial movements (mouthing and licking) following oral lavage with 0.30% SAC were made 50 min later, 24 hr later, or on postnatal Day 3 (P3). Thus, some animals were in a "shifted" condition in which they first experienced a relatively low concentration of SAC and then a higher one while control rats ("nonshifted") received 0.30% SAC during both taste exposures. Fetuses exhibited evidence of both habituation (with repeated presentation of the 0.30% SAC) and positive contrast effects (PCEs) (following an upward shift in SAC concentration) when retested 50 min after their first exposure to SAC on E19. However, these animals did not exhibit PCEs 24 hr later or 5 days later (on P3). Contrast effects were not observed when the initial SAC exposure was on E18, and habituation responses were variable depending on the time interval between the taste presentations to these animals. Rats with a 5- to 6-day latency between the two taste presentations showed neither PCEs nor habituation. Our data indicate that PCEs and habituation effects emerge at different ages, and their demonstration is dependent upon the latency between the taste presentations. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 44: 176,188, 2004. [source] Short-term responses by the German cockroach, Blattella germanica, to insecticidal baits: behavioural observationsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2002Stephen A. Jones Abstract Toxicants may cause insects to avoid a bait, and yet bait efficacy is dependent upon insects ingesting it in adequate quantities. Amounts ingested are, in turn, determined by meal frequency, meal durations and ingestion rate within meals, but to date no report has been made of these variables for domestic cockroaches. We report an experiment in which sixth instar German cockroach, Blattella germanica, nymphs were initially able to self-select their protein and carbohydrate intake independently, then daily at the start of the scotophase some insects had their choice of foods replaced by a single treatment food, which varied through the presence or absence of protein, carbohydrate, and insecticide. Insect behaviour was recorded for the following 5 h, and the data were subsequently subjected to bout analysis in order to identify discrete meals. The age of insects in days on first exposure to a treatment food (,age') and the amount of food eaten in the observation period were both recorded and included in the analysis. Amounts eaten were affected by insect age and food nutrient content, but not by the presence of insecticide. Toxicant effects were, however, seen on average meal duration and meal frequency, in interactions with age and food nutrient effects. These results suggest ways in which direct observations of behaviours may lead to improved bait design. [source] Risk assessment of Magnacide® H herbicide at Río Colorado irrigation channels (Argentina). tier 3: Studies on native speciesENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2007Andrés Venturino Abstract We evaluated the potential environmental risk of the herbicide Magnacide® (Baker Petrolite, TX, USA) using native species from Argentina, representing the ecosystem at the Irrigation Corporation (CORFO) channels at the Colorado River mouth, Buenos Aires, Argentina. Six species including fish, toads, snails, crustaceans, and insects were selected to perform studies on acute toxicity and repeated exposure effects. Magnacide H susceptibility ranking was Bufo arenarum (lethal concentration 50 [LC50] = 0.023 mg/L), Onchorhynchus mykiss (LC50 = 0.038 mg/L), Heleobia parchappii (LC50 = 0.21 mg/L), Hyalella curvispina (LC50 = 0.24 mg/L), Simulium spp. (LC50 = 0.60 mg/L), and Chironomus spp. (LC50 = 2.83 mg/L). The risk limit of 10th percentile (0.013 mg/L) determined by probit analysis on sensitivity distribution was similar to the one calculated from literature data. Risk assessment based on field application data suggested lethal exposures for more than 70 to 90% of the species up to 20 km downstream from the application point. Repeated exposures to Magnacide H of amphibian larvae at the lowest-observed-effect concentration caused some effects during the first exposure, but without cumulative effects. Amphipods were insensitive to repeated exposures, showing no cumulative effects. Whether short-term exposures may result in long-term sublethal effects on the organism's life history was not addressed by these laboratory tests. In conclusion, tier 3 studies indicate that Magnacide H application schedule is extremely toxic for most native species at CORFO,Río Colorado channels, representing a high potential risk in the environment. The real environmental impact must be addressed by field studies at tier 4 giving more information on population effects and communities. [source] Macroinvertebrate community response to pulse exposure with the insecticide lambda-cyhalothrin using in-stream mesocosmsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2005Lars-Henrik Heckmann Abstract esticides are constantly beingapplied to agricultural catchments, but little is known abouttheir impact onaquatic biota during natural exposure. In the present study, the impact of the pyrethroid lambda-cyhalothrin was studied in an in-stream mesocosm setup. Twice during the summer of 2002, the natural macroinvertebrate community was exposed in situ to a 30-min pulse of lambda-cyhalothrin. Pyrethroid doses were released through a modified drip set with nominal concentrations of 0.10, 1.00, and 10.0 ,g L,1 during the first exposure and 0.05, 0.50, and 5.00 ,g L,1 in the second exposure. Before, during, and after exposure, drifting macroinvertebrates were caught in nets. Quantitative benthic samples were taken both before and on two occasions after exposure. Macroinvertebrate drift increased immediately after the pulse exposure, with total drift being significantly higher at all concentrations. Gammarus pulex, various Ephemeroptera, Leuctra sp., and Simuliidae were some of the taxa showing the most pronounced drift response. Structural change in the community was found only at 5.00 and 10.0 ,g L,1, and recovery occurred within approximately two weeks. The present study may be valuable in assessing extrapolations based on laboratory results as well as in evaluating pyrethroid impact on natural freshwater environments. [source] Accumulation of deoxynivalenol and its 15-acetylated form is significantly modulated by oxidative stress in liquid cultures of Fusarium graminearumFEMS MICROBIOLOGY LETTERS, Issue 1 2006Nadia Ponts Abstract Liquid cultures of Fusarium graminearum were supplemented with H2O2 or other oxidative compounds. The accumulation kinetics of the resulting trichothecenes were monitored. At non-lethal concentrations, the H2O2 treatments modulated toxin accumulation, dependent on the method of supplementation. When H2O2 was added at the same time as the inoculation, higher levels of toxins accumulated 30 days later. Conversely, adding H2O2 2 or 7 days after inoculation had little effect. When H2O2 was added daily over the course of the culture, the accumulation of trichothecenes was rapidly and strongly enhanced. The fungus may adapt to oxidative stress when the first exposure to H2O2 occurs at the beginning of the culture course. The highest toxin levels were measured when the H2O2 was added daily. The importance of the first hours of culture was confirmed: pre-treating conidia with H2O2 does not affect their germination kinetics but leads to a reduction in the yield of trichothecenes 40 days later. The H2O2 regulation of this trichothecene accumulation may be specific, as paraquat, another pro-oxidant compound, inhibits their production. Since H2O2 is a major component of the oxidative burst occurring in pathogen/host interactions, these data support the theory that trichothecenes may act as virulence factors. [source] Long-term mortality from pleural and peritoneal cancer after exposure to asbestos: Possible role of asbestos clearanceINTERNATIONAL JOURNAL OF CANCER, Issue 4 2008Francesco Barone-Adesi Abstract Models based on the multistage theory of carcinogenesis predict that the rate of mesothelioma increases monotonically as a function of time since first exposure (TSFE) to asbestos. Predictions of long-term mortality (TSFE , 40 years) are, however, still untested, because of the limited follow-up of most epidemiological studies. Some authors have suggested that the increase in mesothelioma rate with TSFE might be attenuated by clearance of asbestos from the lungs. We estimated mortality time trends from pleural and peritoneal cancer in a cohort of 3,443 asbestos-cement workers, followed for more than 50 years. The functional relation between mesothelioma rate and TSFE was evaluated with various regression models. The role of asbestos clearance was explored using the traditional mesothelioma multistage model, generalized to include a term representing elimination over time. We observed 139 deaths from pleural and 56 from peritoneal cancer during the period 1950,2003. The rate of pleural cancer increased during the first 40 years of TSFE and reached a plateau thereafter. In contrast, the rate of peritoneal cancer increased monotonically with TSFE. The model allowing for asbestos elimination fitted the data better than the traditional model for pleural (p = 0.02) but not for peritoneal cancer (p = 0.22). The risk for pleural cancer, rather than showing an indefinite increase, might reach a plateau when a sufficiently long time has elapsed since exposure. The different trends for pleural and peritoneal cancer might be related to clearance of the asbestos from the workers' lungs. © 2008 Wiley-Liss, Inc. [source] Longevity and fecundity of Eulophus pennicornis, an ectoparasitoid of the tomato moth Lacanobia oleracea, is affected by nutritional state and diet qualityAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2010Maureen E. Wakefield 1Adult female Eulophus pennicornis require a source of nutrition, provided by sources such as pollen, nectar and honeydew or by host feeding, to promote longevity and facilitate egg production. There is potential for parasitoids to be exposed directly to contaminants, including gene products in transgenic crops, through feeding on plant materials, honeydew or hosts. Among such potential contaminants are lectins such as Galanthus nivalis agglutinin (GNA) and concanavalin agglutinin (Con A). 2The effect of direct exposure to honey diets containing GNA and Con A on the longevity and fecundity of E. pennicornis was examined. These lectins have been expressed in a number of plant species for the control for various insect pests. Both GNA and Con A significantly reduced longevity and fecundity at the highest concentration used (0.5% w/v). The effect on fecundity was shown to be related to a reduction in longevity. 3Examination of the gustatory response of adult female E. pennicornis to honey diet containing 1% w/v GNA or Con A revealed no significant differences in consumption rate on first exposure. A significant reduction in the time spent feeding on diet containing 1% Con A was found on the second exposure to the diet. This could have been the result of either a conditioned aversion response or the intoxication of the insect. The effect of Con A on longevity and fecundity could have been, in part, a result of reduced food intake. 4Studies on nutrition and egg resorption demonstrated that the availability of honey solution prolongs the longevity of E. pennicornis and the lack of a source of nutrition promotes oosorption. 5A greater understanding of feeding behaviour and ovigeny is required to understand fully the potential ecological consequence of transgenic crops on parasitoid species through routes of direct exposure to transgene products. [source] Inter-subtype cross-neutralizing antibodies recognize epitopes on cell-associated HIV-1 virionsJOURNAL OF MEDICAL VIROLOGY, Issue 2 2003Helen Donners Abstract HIV-1 infected individuals with cross-neutralizing antibodies against primary HIV-1 isolates belonging to Group M (env A-H) and O, are identified. To investigate the neutralization-kinetics of primary isolates with these antibodies, different neutralization assay conditions are compared. Each set is summarized as a/b/c where a is the time in hours for which antibody is incubated with virus, b is the time in hours allowed for virus to absorb to cells, c is the total culture period in days, from the cells' first exposure to virus, before antigen production (peripheral blood mononuclear cells) or number of fluorescent cells (GHOST) are measured. In HIV-infected individuals, neutralizing antibodies can be detected against a wide range of primary isolates (Group M; A,H and Group O) in PBMC-assays with short incubation phases (1/2/7 or 1/24/7). If cultures are extended (1/2/14 or 1/24/14), however, neutralization can be lost. In kinetic experiments, neutralization can even be seen without pre-incubation (a,=,0 hr). This study shows that neutralization of primary HIV isolates by cross-reactive antibodies can continue after the virus has bound to its target cell. This neutralization, however, is not an all or nothing loss in virus infectivity. Most often it leads only to a reduction in viral replication rates. J. Med. Virol. 69:173,181, 2003. © 2003 Wiley-Liss, Inc. [source] Vitamin D production in psoriasis patients increases less with narrowband than with broadband ultraviolet B phototherapyPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 3 2009Amra Osmancevic Background: Phototherapy of psoriasis is an effective treatment. In addition to standard broadband ultraviolet radiation B (UVB), (280,320 nm), narrowband phototherapy (NBUVB) (monochromatic UV between 311 and 312 nm) has become an important treatment for psoriasis. The same wavelength range of UVB (290,315 nm) induces synthesis of vitamin D. The aim was to compare the effect of broadband with NBUVB therapy on vitamin D synthesis in patients with psoriasis. Methods: Sixty-eight Caucasian patients (17 women and 51 men) mean age 54.1 ± 16.0 years, with active plaque psoriasis, were treated with broadband UVB (n=26) or NBUVB (n=42) two to three times/week for 8,12 weeks. The serum concentrations of 25-hydroxyvitamin D (25(OH)D3), 1,25-dihydroxyvitamin D (1,25(OH)2D3), intact parathyroid hormone (PTH), calcium and creatinine were measured before the first exposure and after the last dose of radiation. Results: In broadband UVB treated patients, 25(OH)D3 increased from 37.9 ± 16.9 to 69.4 ± 19.7 ng/ml (P<0.0001) and in patients treated with NBUVB from 34.8 ± 11.9 to 55.3 ± 17.6 ng/ml (P<0.0001) and P=0.008 between the treatment groups. PTH decreased on broadband UVB (P<0.05). The serum concentrations of 1,25(OH)2D3, calcium or creatinine remained unaltered. Conclusion: Serum 25(OH)D3 in psoriasis patients increased less with NBUVB than with broadband UVB phototherapy. Psoriasis improved on both regimens. [source] Exposure to respirable dust and crystalline silica in bricklaying education at Dutch vocational training centersAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 6 2010Daan Huizer MSc Abstract Background Construction workers are educated at vocational training centers before they begin their working lives. Future bricklayers and their instructors are exposed to respirable dust and possibly to hazardous respirable crystalline silica from trial mortar. Methods Thirty-six personal air samples were collected at six training centers to estimate exposure to respirable dust for both students and teachers. A selection of 22 samples was analyzed for crystalline silica. Results Average respirable dust exposures ranged from 0.59,mg/m3 for teachers to 1.45,mg/m3 for students performing recycling and cleaning tasks. In 45% of the analyzed samples, respirable crystalline silica was detected. Exposure to silica remained below the Dutch OEL (75,µg/m3). Exposure was significantly less for teachers than for students. This effect was found in both types of vocational training centers present in the Netherlands. Dry sweeping, as performed at all locations in this study, contributed considerably to the exposure to respirable dust. A first step in reducing exposure to dust and silica at training centers would therefore be to avoid dry sweeping. The presence of a dust extraction system, although not optimally designed, also significantly lowered exposure. Conclusions To assess a construction worker's lifetime exposure to respirable dust and crystalline silica, the vocational training period should also be taken into account. Several epidemiological studies have shown that time since first exposure can be an important risk factor for chronic health effects. Am. J. Ind. Med. 53: 628,634, 2010. © 2010 Wiley-Liss, Inc. [source] Beryllium lymphocyte proliferation test surveillance identifies clinically significant beryllium diseaseAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 10 2009Margaret M. Mroz MSPH Abstract Background Workplace surveillance identifies chronic beryllium disease (CBD) but it remains unknown over what time frame mild CBD will progress to a more severe form. Methods We examined physiology and treatment in 229 beryllium sensitization (BeS) and 171 CBD surveillance-identified cases diagnosed from 1982 to 2002. Never smoking CBD cases (81) were compared to never smoking BeS patients (83) to assess disease progression. We compared CBD machinists to non-machinists to examine effects of exposure. Results At baseline, CBD and BeS cases did not differ significantly in exposure time or physiology. CBD patients were more likely to have machined beryllium. Of CBD cases, 19.3% went on to require oral immunosuppressive therapy. At 30 years from first exposure, measures of gas exchange were significantly worse and total lung capacity was lower for CBD subjects. Machinists had faster disease progression as measured by pulmonary function testing and gas exchange. Conclusions Medical surveillance for CBD identifies individuals at significant risk of disease progression and impairment with sufficient time since first exposure. Am. J. Ind. Med. 52:762,773, 2009. © 2009 Wiley-Liss, Inc. [source] Asbestos exposure and benign asbestos diseases in 772 formerly exposed workers: Dose,response relationshipsAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 8 2009Giuseppe Mastrangelo MD Abstract Background Since previous studies have provided conflicting results, we investigated the relationship between the risk of benign asbestos-related diseases and different aspects of asbestos exposure in previous asbestos workers who underwent low-dose computed tomography (CT). Methods CT scans were carried out in 772 subjects. A questionnaire was employed to collect data on smoking habits and duration, peak and cumulative exposure, and time since first exposure to asbestos. Multiple logistic regression models with stepwise selection of variables were used to evaluate the associations. Results Fourteen (1.8%) cases of asbestosis, 187 (24.2%) of pleural plaques (PP), and 50 (6.5%) of diffuse pleural thickening (DPT) were found. The significant risk factors were: cumulative exposure for asbestosis (P for trend,=,0.004); time since first exposure (P for trend <0.001), and peak exposure (P for trend <0.001) for PP; and time since first exposure for DPT (P for trend,=,0.024). Conclusions Parenchymal asbestosis and PP are associated with different aspects of asbestos exposure. DPT appears to be less specific for asbestos exposure. Am. J. Ind. Med. 52:596,602, 2009. © 2009 Wiley-Liss, Inc. [source] Asbestos-related disease among sheet metal workers 1986,2004: Radiographic changes over time,,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 7 2009FACOEM, Laura S. Welch MD Abstract Background In 1985, the Sheet Metal Workers International Association and the Sheet Metal and Air Conditioning National Association formed The Sheet Metal Occupational Health Institute Trust (SMOHIT) to examine the health hazards of the sheet metal industry. Between 1986 and 2004 18,211 individuals were examined. At the time of the first examination 9.6% of all participants (1,745) had findings consistent with parenchymal disease (ILO,>,1/0), and 21% (3,827) had pleural scarring. Methods 2181-Two thousand hundred eighty-one who had no radiographic evidence of pneumoconiosis on baseline examination underwent a second examination. Results By the second examination, 5.3% had developed parenchymal disease on chest radiograph; an additional 12.4% had developed pleural scarring without parenchymal disease. Factors that predicted new cases of pneumoconiosis on radiograph were the calendar year the worker entered the sheet metal trade, smoking, and shipyard work. Forty-seven percent of those smoking at the time of initial exam reported having quit smoking by the second examination. Conclusions Asbestosis is still occurring 50 years after first exposure. Exposed workers benefit from medical screening programs that incorporate smoking cessation. Am. J. Ind. Med. 52:519,525, 2009. © 2009 Wiley-Liss, Inc. [source] Non-malignant asbestos-related diseases in Brazilian asbestos-cement workersAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 3 2001E. Algranti MD Abstract Background Production of asbestos-cement products in Brazil started in the 1940s, peaked in the 60,70s and is still an active industry. This study was designed to assess the non-malignant effects of asbestos exposure in the asbestos-cement industry in Brazil. Methods A group of 828 former asbestos-cement workers enrolled in a cross-sectional and cohort study of respiratory morbidity, submitted to a detailed occupational history, respiratory symptoms questionnaire, spirometry, PA chest x-ray, and high resolution computed chest tomography (HRCT). Asbestos exposure was assessed by years of exposure, cumulative exposure (a semi-quantitative method), and latency time from first exposure. Asbestosis and pleural thickening were assessed according to HRCT criteria. Results Asbestosis was present in 74 (8.9%) and pleural thickening in 246 (29.7%). Using the HRCT as the "best available evidence", it was shown that were more false negatives than false positives in the x-ray readings for parenchymal (21.6% false negatives, 4.2% false positives) and pleural (26.0% false negatives, 14.4% false positives) diseases due to asbestos. Latency time from first exposure was the best predictor for both asbestosis and pleural thickening. Subjects in the higher exposure groups presented lower levels of lung function. Obstructive defects were significantly related to smoking, shortness of breath, body mass index, and age, whereas restrictive defects were related to asbestosis, shortness of breath, and latency time. Chronic bronchitis increased with latency time in the three smoking groups and was significantly related to pleural thickening (OR 1.56 (1.00,2.42)). Shortness of breath was significantly associated with body mass index and pleural thickening (OR 1.30 (1.24,2.09)). Conclusions Pleural thickening and asbestosis showed a significant association with latency time and exposure. FVC and FEV1 decreased across increasing profusion with an added effect of pleural thickening. There was a significant and independent effect of exposure on lower levels of FVC and FEV1. Obstructive defects were mainly related to smoking and restriction to asbestosis. Dust exposure and smoking were synergistic in increasing chronic bronchitis and shortness of breath report. Shortness of breath report was also related to pleural thickening and higher body mass index. Am. J. Ind. Med. 40:240,254, 2001. © 2001 Wiley-Liss, Inc. [source] Baboon vaginal microbiota: an overlooked aspect of primate physiologyAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2010Angel J. Rivera Abstract The bacterial population of the primate vaginal canal is an infant primate's first exposure to the microbial population inhabiting the outside world. Yet, little is known about this population and the effect it might have on the development and survival of the infant primate. As a first step toward characterizing the vaginal microbiota of a nonhuman primate, we used denaturing gradient gel electrophoresis to evaluate variations in the vaginal microbiota of a group of 35 baboons (Papio hamadryas), which were housed in a facility where they shared the same diet and the same environmental conditions. We found that, despite the uniform environment, there were appreciable differences in the composition of the microbiota from one individual to another. Our results also indicate that a simple swab test is sufficient for sampling the vaginal microbiota in the field, a finding that should help make more detailed characterization of the microbiota of wild primates feasible in the future. Am. J. Primatol. 72:467,474, 2010. © 2010 Wiley-Liss, Inc. [source] ORIGINAL RESEARCH,EPIDEMIOLOGY: The Incidence of Invasive Breast Cancer Among Women Prescribed Testosterone for Low LibidoTHE JOURNAL OF SEXUAL MEDICINE, Issue 7 2009Susan R. Davis MD ABSTRACT Introduction., Although the efficacy of testosterone for the treatment of hypoactive sexual desire disorder is well established, the effect of testosterone therapy on breast cancer risk remains uncertain. Aim., The incidence of invasive breast cancer among past and current testosterone users. Methods., Retrospective cohort study of 631 women ever treated with testosterone between January 1989 and December 2007 in a clinical endocrinology practice. Main Outcome Measure., The incidence of invasive breast cancer since first exposure, and the standardized incidence rate ratio (IRR) calculated using Australian age-specific incidence rates for 2005. Results., The mean age of the women at first exposure to testosterone therapy was 49.1 ± 8.2 years, median treatment duration, 1.3 years, and mean follow-up of 6.7 ± 4.6 years, providing 4,015 woman-years of follow-up. Twelve cases of invasive breast cancer occurred among 599 women breast cancer-free before treatment, giving an age adjusted IRR of 1.35 (95% confidence interval 0.76,2.38). There was no evidence of an independent effect of duration of exposure on breast cancer risk. Conclusion., In this study, testosterone use was not associated with a significant increase in breast cancer risk. Davis SR, Wolfe R, Farrugia H, Ferdinand A, and Bell RJ. The incidence of invasive breast cancer among women prescribed testosterone for low libido. J Sex Med 2009;6:1850,1856. [source] Trichostrongylus colubriformis and Haemonchus contortus infections in light bodyweight Merino lambsAUSTRALIAN VETERINARY JOURNAL, Issue 11 2007SJ McClure Objective To show that low bodyweight is a predisposing cause of high Trichostrongylus colubriformis and Haemonchus contortus burdens and egg counts in Merino lambs. Design A comparison was made, among lambs of different bodyweights, on the effect on immunity of a primary or secondary viable infection with T colubriformis or H contortus larvae. Procedure Sixty-one Merino lambs, 1 or 6 months of age, were penned indoors and given primary, or both primary and secondary, infection of T colubriformis or H contortus. Faecal egg counts, worm counts and parasite-specific immunoglobulin concentrations were examined for their relationships with bodyweight. Results Bodyweight at the start of a primary infection was correlated with worm burden, worm fecundity and jejunal IgA antibody concentration. Merino lambs weighing less than 23 kg at the time of first exposure to T colubriformis or H contortus had impaired ability to develop protective mucosal immunity and to resist homologous challenge. Conclusion If the goal is to ensure that lambs develop immunity before weaning, then every endeavour should be made to achieve the combination of critical bodyweight and exposure to moderate levels of nematode infection as soon as possible. [source] Atomic Layer Deposition, Characterization, and Dielectric Properties of HfO2/SiO2 Nanolaminates and Comparisons with Their Homogeneous Mixtures,CHEMICAL VAPOR DEPOSITION, Issue 2-3 2006L. Zhong Abstract Nanolaminates of HfO2 and SiO2 were prepared using atomic layer deposition (ALD) methods. Successive exposure of substrates maintained at 120 or 160,°C to nitrogen flows containing Hf(NO3)4 and (tBuO)3SiOH led to typical bilayer spacings of 2.1,nm, with the majority of each bilayer being SiO2. The density of the SiO2 layers (measured using X-ray reflectometry (XRR)) was slightly higher than expected for amorphous silica, suggesting that as much as 10,% HfO2 was incorporated into the silica layers. Based on cross-sectional transmission electron microscopy (TEM) and XRR, oxidation of the silicon substrate was observed during its first exposure to Hf(NO3)4, leading to a SiO2 interfacial layer and the first HfO2 layer. Combining the ALD of Hf(NO3)4/(tBuO)3SiOH with ALD cycles involving Hf(NO3)4 and H2O allowed the systematic variation of the HfO2 thickness within the nanolaminate structure. This provided an approach towards controlling the dielectric constant of the films. The dielectric constant was modeled by treating the nanolaminate as a stack of capacitors wired in series. The nanolaminate structure inhibited the crystallization of the HfO2 in post-deposition annealing treatments. As the HfO2 thickness decreased, the preference for the tetragonal HfO2 phase increased. [source] The changing face of food hypersensitivity in an Asian communityCLINICAL & EXPERIMENTAL ALLERGY, Issue 7 2007W. C. Chiang Summary Background Food allergy seems to be increasing in Asia as well as world-wide. Our aim was to characterize food protein sensitization patterns in a population of Asian children with possible food allergy. Methods Children presenting to our allergy clinic over 3 years with symptomatic allergic disease and at least one specific food allergen sensitization documented on skin prick testing were included in the analysis. Results Two hundred and twenty-seven patients fulfilled inclusion criteria. Ninety (40%) of the positive skin tests were positive to egg, 87 (39%) to shellfish, 62 (27.3%) to peanut, 30 (13.2%) to fish, 27 (11.8%) to cow's milk, 21 (9.3%) to sesame, 13 (3.7%) to wheat and eight (3.2%) to soy. Peanut sensitization was the third most common sensitizing allergen, and seen mostly in young atopic children with multiple food hypersensitivities and a family history of atopic dermatitis. The median reported age of first exposure to fish and shellfish was 6 and 12 months, respectively. The mean age at presentation of children with shellfish hypersensitivity was at 6.7 years of age. The likelihood of shellfish sensitization was increased in children with concomitant sensitization to cockroaches. Conclusions In contrast to previously reported low peanut allergy rates in Asia, in our review, peanut sensitization is present in 27% (62/227) of food-allergic children, mostly in patients with multiple food protein sensitizations. Temporal patterns of first exposure of infants to fish and shellfish are unique to the Asian diet. Shellfish are a major sensitizing food source in Asian children, especially in allergic rhinitis patients sensitized to cockroaches. [source] Ludwik Maurycy Hirschfeld (1814,1876)CLINICAL ANATOMY, Issue 3 2008Jerzy Reymond Abstract It is rare to encounter exceptional individuals such as Ludwik Maurycy Hirschfeld. He was born into poverty and early on discovered his passion for medicine, particularly anatomy. His life is a testament to what pure human determination can achieve. He overcame societal and financial obstacles, ultimately becoming a physician, anatomist, and scientist. In 1834, Hirshfeld left Poland for France. His first exposure to medical anatomy came while under the direction of the great anatomist Professor Bourgery at École Pratique de Médicine. In 1848, he earned his degree in medicine and published his work "Des injections capillaires." He coupled his love of anatomy with teaching and research. Hirschfeld's skills, as a dissector, enabled him to prepare specimens for illustration, which produced some of the anatomy atlases of modern times. "The Descriptive Anatomy of the Human Body" is one of his most influential works. Dr. Hirschfeld pioneered the initial illustrations of the meninges of brain. There are many anatomical structures named after him, including Hirschfeld's nerves and anastomoses. Hirshfeld remained as a professor until 1875. His death in 1876 was a great loss to the scientific community. His scientific accomplishments were astounding but he should also be remembered as a great humanitarian, an individual who offered medical treatment to the poor, and who strived to instill in his students a passion for anatomy. Clin. Anat. 21: 225,232, 2008. © 2008 Wiley-Liss, Inc. [source] | ||||||||||||||||