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141.
Walters PH Jezequel JJ Grove MB 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(3):867-872
The purpose of this case study was to examine the bone mineral density (BMD) of 2 women, aged 48 and 54 years, who had engaged in high-intensity resistance training for >30 years each and gained national prominence for their lifting performances. Each subject was measured using a dual x-ray absorptiometry (GE Lunar Prodigy, Fairfield, CT, USA) for both the BMD (grams per centimeter squared) and bone mineral content (grams) of the lumbar spine, dual femur, and total body. The Z and T scores of the 49-year-old subject were significantly higher than either age and gender-matched or peak BMD norms (lumbar spine Z + 2.2, T + 1.8, femoral mean Z + 1.1, T + 0.6, total body Z + 2.4, T + 2.0). The Z and T scores of the 54-year-old mark the largest ever reported in the literature for a Caucasian woman of this age (lumbar spine Z + 2.8, T + 2.2, femoral mean Z + 1.4, T + 1.9, total body Z + 2.6, T + 3.0). Although these results do not prove any causal relationship between long-term high-intensity strength training and elevated BMDs among women, they do raise questions that some type of relationship may exist. 相似文献
142.
ML Zupancic BL Cantarel Z Liu EF Drabek KA Ryan S Cirimotich C Jones R Knight WA Walters D Knights EF Mongodin RB Horenstein BD Mitchell N Steinle S Snitker AR Shuldiner CM Fraser 《PloS one》2012,7(8):e43052
Obesity has been linked to the human gut microbiota; however, the contribution of gut bacterial species to the obese phenotype remains controversial because of conflicting results from studies in different populations. To explore the possible dysbiosis of gut microbiota in obesity and its metabolic complications, we studied men and women over a range of body mass indices from the Old Order Amish sect, a culturally homogeneous Caucasian population of Central European ancestry. We characterized the gut microbiota in 310 subjects by deep pyrosequencing of bar-coded PCR amplicons from the V1-V3 region of the 16S rRNA gene. Three communities of interacting bacteria were identified in the gut microbiota, analogous to previously identified gut enterotypes. Neither BMI nor any metabolic syndrome trait was associated with a particular gut community. Network analysis identified twenty-two bacterial species and four OTUs that were either positively or inversely correlated with metabolic syndrome traits, suggesting that certain members of the gut microbiota may play a role in these metabolic derangements. 相似文献
143.
Background
Anxiety is common, with significant morbidity, but little is known about presentations and recording of anxiety diagnoses and symptoms in primary care. This study aimed to determine trends in incidence and socio-demographic variation in General Practitioner (GP) recorded diagnoses of anxiety, mixed anxiety/depression, panic and anxiety symptoms.Methodology/Principal Findings
Annual incidence rates of anxiety diagnoses and symptoms were calculated from 361 UK general practices contributing to The Health Improvement Network (THIN) database between 1998 and 2008, adjusted for year of diagnosis, gender, age, and deprivation. Incidence of GP recorded anxiety diagnosis fell from 7.9 to 4.9/1000PYAR from 1998 to 2008, while incidence of anxiety symptoms rose from 3.9 to 5.8/1000PYAR. Incidence of mixed anxiety/depression fell from 4.0 to 2.2/1000PYAR, and incidence of panic disorder fell from 0.9/1000PYAR in 1998 to 0.5/1000PYAR in 2008. All these entries were approximately twice as common in women and more common in deprived areas. GP-recorded anxiety diagnoses, symptoms and mixed anxiety/depression were commonest aged 45–64 years, whilst panic disorder/attacks were more common in those 16–44 years. GPs predominately use broad non-specific codes to record anxiety problems in the UK.Conclusions/Significance
GP recording of anxiety diagnoses has fallen whilst recording of anxiety symptoms has increased over time. The incidence of GP recorded diagnoses of anxiety diagnoses was lower than in screened populations in primary care. The reasons for this apparent under-recording and whether it represents under-detection in those being seen, a reluctance to report anxiety to their GP, or a reluctance amongst GPs to label people with anxiety requires investigation. 相似文献144.
LD Pound SA Sarkar A Ustione PK Dadi MK Shadoan CE Lee JA Walters M Shiota OP McGuinness DA Jacobson DW Piston JC Hutton DR Powell RM O'Brien 《PloS one》2012,7(7):e40972
Objective
The SLC30A8 gene encodes the islet-specific transporter ZnT-8, which is hypothesized to provide zinc for insulin-crystal formation. A polymorphic variant in SLC30A8 is associated with altered susceptibility to type 2 diabetes. Several groups have examined the effect of global Slc30a8 gene deletion but the results have been highly variable, perhaps due to the mixed 129SvEv/C57BL/6J genetic background of the mice studied. We therefore sought to remove the conflicting effect of 129SvEv-specific modifier genes.Methods
The impact of Slc30a8 deletion was examined in the context of the pure C57BL/6J genetic background.Results
Male C57BL/6J Slc30a8 knockout (KO) mice had normal fasting insulin levels and no change in glucose-stimulated insulin secretion (GSIS) from isolated islets in marked contrast to the ∼50% and ∼35% decrease, respectively, in both parameters observed in male mixed genetic background Slc30a8 KO mice. This observation suggests that 129SvEv-specific modifier genes modulate the impact of Slc30a8 deletion. In contrast, female C57BL/6J Slc30a8 KO mice had reduced (∼20%) fasting insulin levels, though this was not associated with a change in fasting blood glucose (FBG), or GSIS from isolated islets. This observation indicates that gender also modulates the impact of Slc30a8 deletion, though the physiological explanation as to why impaired insulin secretion is not accompanied by elevated FBG is unclear. Neither male nor female C57BL/6J Slc30a8 KO mice showed impaired glucose tolerance.Conclusions
Our data suggest that, despite a marked reduction in islet zinc content, the absence of ZnT-8 does not have a substantial impact on mouse physiology. 相似文献145.
Julissa Roncal Joyce Maschinski Bruce Schaffer S. Michael Gutierrez Donald Walters 《Journal for Nature Conservation》2012,20(2):109-116
In the next century, safeguarding plant species against extinction from complete land conversion may require introducing species to novel locations. Although regulatory agencies caution against translocation outside of known historic ranges, when most wild populations and their habitats have been severely altered few viable options may be available for conserving rare plants. We introduced 345 endangered Amorpha herbacea var. crenulata along a pine rockland/transverse glade gradient with similar attributes to historically known occurrences for south Florida, USA, and monitored their survival and growth for five years. The experimental phase addressed: (1) Is the recipient site suitable for colonisation of this species despite hydrological manipulation in the region? (2) Can translocated plants grow equally well in four microhabitats along a gradient within the recipient site? We characterised soil water content, soil nutrient, and vegetation cover to assess the microhabitats at the recipient site. From 2006 to 2008 plants survived in all four microhabitats, but had highest survival in pineland. Translocated plants grew best in microhabitats with less grass cover and higher P content – the pineland and the restoration glade. Through 2008 we observed consistently higher soil water content with less total vegetation cover in pineland and significantly higher P content in the restoration glade.Using 2006–2008 data, we implemented the adaptive management phase, moving 20 plants from the lowest survival microhabitat to the highest survival microhabitat. This tactic improved the survival of plants by 2011, though growth rates of moved plants did not improve. Short-distance translocation, assessing environmental attributes related to plant survival and growth, quantifying similarity of soil, temperature, precipitation, and community as in this study are recommended to evaluate prospective introduction sites for translocations within or outside of range. 相似文献
146.
147.
Suri A Walters JJ Rohrs HW Gross ML Unanue ER 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(6):3849-3856
The diversity of Ags targeted by T cells in autoimmune diabetes is unknown. In this study, we identify and characterize a limited number of naturally processed peptides from pancreatic islet beta-cells selected by diabetogenic I-A(g7) molecules of NOD mice. We used insulinomas transfected with the CIITA transactivator, which resulted in their expression of class II histocompatibility molecules and activation of diabetogenic CD4 T cells. Peptides bound to I-A(g7) were isolated and examined by mass spectrometry: some peptides derived from proteins present in secretory granules of endocrine cells, and a number were shared with cells of neuronal lineage. All proteins to which peptides were identified were expressed in beta cells from normal islets. Peptides bound to I-A(g7) molecules contained the favorable binding motif characterized by acidic amino acids at the P9 position. The draining pancreatic lymph nodes of prediabetic NOD mice contained CD4 T cells that recognized three different natural peptides. Furthermore, four different peptides elicited CD4 T cells, substantiating the presence of such self-reactive T cells. The overall strategy of identifying natural peptides from islet beta-cells opens up new avenues to evaluate the repertoire of self-reactive T cells and its role in onset of diabetes. 相似文献
148.
Andrew G. S. Cuthbertson James J. Mathers Phil Northing Anthony J. Prickett Keith F. A. Walters 《Insect Science》2008,15(5):447-453
The integration of chemical insecticides and infective juveniles of the entomopathogenic nematode Steinernema carpocapsae (Wesier) (Nematoda: Steinernematidae), to control second instars of the sweetpotato whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) was investigated. Using a sand bioassay, the effects of direct exposure of S. carpocapsae for 24 h to field rate dilutions of four insecticides (spiromesifen, thiacloprid, imidacloprid and pymetrozine) on infectivity to Galleria mellonella larvae were tested. Although all chemicals tested, except spiromesifen, produced acceptable nematode infectivity rates, they were all significantly less than the water control. The effect of insecticide treatment (dry residues of spiromesifen, thiacloprid and pymetrozine and soil drench of imidacloprid) on the efficacy of the nematode against B. tabaci was also investigated. Nematodes in combination with thiacloprid and spiromesifen gave higher B. tabaci mortality (86.5% and 94.3% respectively) compared to using nematodes alone (75.2%) on tomato plants. There was no significant difference in B. tabaci mortality when using the chemicals imidacloprid, pymetrozine and spiromesifen in conjunction with nematodes compared to using the chemicals alone. However, using thiacloprid in combination with the nematodes produced significantly higher B. tabaci mortality than using the chemical alone. The integration of S. carpocapsae and these chemical agents into current integrated pest management programmes for the control of B. tabaci is discussed. 相似文献
149.
DANUTA WASSERMAN TRAN THI HOUNG THANH PHAM THI DUC MINH MAX GOLDSTEIN ANA NORDENSKIÖLD CAMILLA WASSERMAN 《World psychiatry》2008,7(1):47-53
The study aimed to explore the suicidal process, suicidal communication and psychosocial situation of young suicide attempters in a rural community in Hanoi, Vietnam. Semi-structured interviews were conducted, in a community setting, with 19 suicide attempters aged 15-24 who had been consecutively hospitalized in an intensive care unit. In 12 of 19 cases, the first pressing, distinct and constant suicidal thoughts appeared less than one day before the suicide attempt in question. However, distress and mild, fleeting suicidal thoughts had been present up to six months before the suicide attempt in 16 cases. Five respondents had a suicide plan one to three days before attempting suicide. Altogether, 13 engaged in some form of suicidal communication before their attempt. This communication was, however, difficult for outsiders to interpret. Twelve of the respondents were victims of regular physical abuse and 16 had suffered psychological violence for at least one year before attempting suicide. Eighteen of the respondents used pesticides or raticides in their suicide attempts. None sought advice or consultation in the community despite long-standing psychosocial problems. The strategy of reducing the availability of suicide means (e.g., pesticides or raticides) in Asian countries should be complemented with a long-term suicide-preventive strategy that targets school dropouts and domestic violence, and promotes coping abilities and communication about psychological and social problems as well as recognition of signs of distress and suicidal communication. 相似文献
150.
Troedsson C Lee RF Walters T Stokes V Brinkley K Naegele V Frischer ME 《Applied and environmental microbiology》2008,74(14):4346-4353
Recently, we described a novel denaturing high-performance liquid chromatography (DHPLC) approach useful for initial detection and identification of crustacean parasites. Because this approach utilizes general primers targeted to conserved regions of the 18S rRNA gene, a priori genetic sequence information on eukaryotic parasites is not required. This distinction provides a significant advantage over specifically targeted PCR assays that do not allow for the detection of unknown or unsuspected parasites. However, initial field evaluations of the DHPLC assay suggested that because of PCR-biased amplification of dominant host genes it was not possible to detect relatively rare parasite genes in infected crab tissue. Here, we describe the use of a peptide nucleic acid (PNA) PCR hybridization blocking probe in association with DHPLC (PNA-PCR DHPLC) to overcome inherent PCR bias associated with amplification of rare target genes by use of generic primers. This approach was utilized to detect infection of blue crabs (Callinectes sapidus) by the parasitic dinoflagellate Hematodinium sp. Evaluation of 76 crabs caught in Wassaw Sound, GA, indicated a 97% correspondence between detection of the parasite by use of a specific PCR diagnostic assay and that by use of PNA-PCR DHPLC. During these studies, we discovered one crab with an association with a previously undescribed protist symbiont. Phylogenetic analysis of the amplified symbiont 18S rRNA gene indicated that it is most closely related to the free-living kinetoplastid parasite Procryptobia sorokini. To our knowledge, this is the first report of this parasite group in a decapod crab and of this organism exhibiting a presumably parasitic life history. 相似文献