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One Individual (one + individual)
Kinds of One Individual Selected AbstractsDoes Mediastinitis Affect the Graft Patency?JOURNAL OF CARDIAC SURGERY, Issue 3 2005Denyan Mansuro, lu M.D. There are many studies that have focused on the graft patency. But, till now, no study has been done to detect the effects of mediastinitis to graft patency. So, we aimed to detect the effect of mediastinitis on the graft patency in patients who have undergone coronary artery bypass surgery. Sixteen of 45 patients who have been operated upon for coronary artery bypass surgery and developed mediastinitis, which was treated with open drainage and mediastinal irrigation with late wound closure, were included in the study. The mean age of the patients was 55 ± 11 (range 35,69) and nine of the patients were male. The graft patency was evaluated with control coronary angiographies after a mean period of 30.42 ± 43.17 months (range 1,132). The left internal thoracic artery was patent in all patients (100%). Right internal thoracic artery patency rate was 50% (1/2). One individual bypassed radial artery was patent, whereas the sequential bypassed graft was occluded. The patency ratio of radial artery anastomosis was 33% (1/3). Twelve of the 17 saphenous vein grafts were patent (70.58%). The total number of patent distal anastomosis was 30/38 (78.94%). When compared with the graft patency of patients without infection, it was found that mediastinitis does not affect the graft patency rates adversely. [source] Introgressive hybridization of human and rodent schistosome parasites in western KenyaMOLECULAR ECOLOGY, Issue 23 2008MICHELLE L. STEINAUER Abstract Hybridization and introgression can have important consequences for the evolution, ecology and epidemiology of pathogenic organisms. We examined the dynamics of hybridization between a trematode parasite of humans, Schistosoma mansoni, and its sister species, S. rodhaini, a rodent parasite, in a natural hybrid zone in western Kenya. Using microsatellite markers, rDNA and mtDNA, we showed that hybrids between the two species occur in nature, are fertile and produce viable offspring through backcrosses with S. mansoni. Averaged across collection sites, individuals of hybrid ancestry comprised 7.2% of all schistosomes collected, which is a large proportion given that one of the parental species, S. rodhaini, comprised only 9.1% of the specimens. No F1 individuals were collected and all hybrids represented backcrosses with S. mansoni that were of the first or successive generations. The direction of introgression appears highly asymmetric, causing unidirectional gene flow from the rodent parasite, S. rodhaini, to the human parasite, S. mansoni. Hybrid occurrence was seasonal and most hybrids were collected during the month of September over a 2-year period, a time when S. rodhaini was also abundant. We also examined the sex ratios and phenotypic differences between the hybrids and parental species, including the number of infective stages produced in the snail host and the time of day the infective stages emerge. No statistical differences were found in any of these characteristics, and most of the hybrids showed an emergence pattern similar to that of S. mansoni. One individual, however, showed a bimodal emergence pattern that was characteristic of both parental species. In conclusion, these species maintain their identity despite hybridization, although introgression may cause important alterations of the biology and epidemiology of schistosomiasis in this region. [source] A RYR1 mutation associated with recessive congenital myopathy and dominant malignant hyperthermia in Asian familiesMUSCLE AND NERVE, Issue 4 2009Danielle Carpenter PhD Abstract In this study we present 3 families with malignant hyperthermia (MH), all of Indian subcontinent descent. One individual from each of these families was fully sequenced for RYR1 and presented with the non-synonymous change c.11315G>A/p.R3772Q. When present in the homozygous state c.11315*A is associated with myopathic symptoms. Muscle Nerve, 2009 [source] Hospitalization in Winnipeg, Canada due to occupational disease: A pilot studyAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 5 2009Allen G. Kraut MD, FRCPC Abstract Background The objectives of this study were to identify the extent of occupational exposures to hazardous substances amongst male medical inpatients and to determine the extent to which these exposures may have contributed to the development of medical conditions. Methods A random sample of 297 male who were admitted from outside the hospital to the medical wards to a large tertiary care hospital, were between age 18,75 and could communicate in English completed an occupational history questionnaire. This information was merged with an inpatient database which contained patient demographics, admission diagnoses, and co-morbidity data. A specialist in occupational medicine and internal medicine determined whether the medical conditions the participants had were related to their exposures. Results One individual had a condition causing admission that was related to his work and 12 others (4%) had a condition that was possibly related to their work which had caused symptoms. One additional individual was found to have asymptomatic asbestos related pleural fibrosis. Fourteen of 37 possible harmful occupational exposures were reported by more than 10% of the study participants. On average each participant reported 5.5 exposures. Conclusions Occupational exposures to male medical inpatients are common. For 4.4% (13/297) of male admissions to the general medical wards from the emergency room occupational factors may have played a role in the development of medical conditions which led to admission or to major co-morbidities. Detailed occupational histories will likely lead to more suspected cases of work related medical admissions. Am. J. Ind. Med. 52:372,379, 2009. © 2009 Wiley-Liss, Inc [source] Patellar dislocation in Kabuki syndromeAMERICAN JOURNAL OF MEDICAL GENETICS, Issue 2 2002Kenji Kurosawa Abstract We describe four individuals (two females and two males) with Kabuki syndrome and recurrent dislocation of the patella. The age of diagnosis of patellar dislocation ranged from 11 to 23 years. One individual underwent excision of the free fragment and transfer of the tibial tuberosity with good outcome. Two required patellar brace for instability. Characteristics of individuals with the syndrome at a high risk of patellar dislocation include female, adolescence or young adulthood, joint laxity, and obesity. © 2002 Wiley-Liss, Inc. [source] Ultrastructure of the Spermatozoa of the Yangtze Finless Porpoise (Neophocaena phocaenoides asiaeorientalis)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2009H. Y. Li Summary Semen sample was collected from two captive adult Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) during physical examination. One individual was aged about 9 years with body length 143 cm (total length) and body weight 46.1 kg in 2003. The age of the other was unknown and its body length was 147 cm and body weight was 43 kg in 2004. Ultrastructure of their spermatozoa was examined using scanning and transmission electron microscope. The sperm concentration was 4.17 × 109 spermatozoa per ml by the cytometer. The approximate dimensions of the spermatozoa were as follows: head length, 3.366 ± 0.140 ,m (mean ± SE, n = 15); head width, 1.896 ± 0.099 ,m (n = 15); and neck length, 1.004 ± 0.074 ,m (n = 10). The tail included midpiece, principal piece and terminal piece. The length of the midpiece was 1.882 ± 0.077 ,m (n = 9). There is no apparent boundary between the principal piece and the terminal piece, so the length of the principal piece and the terminal piece was 44.612 ± 3.485 ,m (n = 5). Total length of the spermatozoa was 53.314 ± 4.580 ,m (n = 10). The acrosome covered approximately 45.8% of the anterior portion of the head. [source] The future: genes, physical activity and healthACTA PHYSIOLOGICA, Issue 4 2010F. W. Booth Abstract The assigned title for the Lindhard presentation was to examine the future of genes, physical activity and health. The current review is a summary of this presentation. Caution is expressed that technology is improving so rapidly that a future view is limited to a few years as opposed to the 100 years passing since Lindhard's achievements. The near futuristic opportunities and challenges for four major topic topics are reviewed here. Concerns are expressed over current usage of the terms ,control' group and ,non-responders' in exercise research. Our view is that ,control' needs to be differentiated between its usage for treatments of exercise to restore natural functions in individuals with less than healthy levels of physical activity and the inherited genome's expectation for physical activity levels to maintain normal function. For the second discussed topic, it is proposed that the term ,non-responders' should be replaced by the term ,low sensitivity' as there may be no such human who is a non-responder to every exercise adaptation. The third futuristic topic is exercise prescription as envisioned for individualized medicine. However, numerous limitations and challenges exist to truly optimal exercise medicine at the level of one individual. Finally, preventative physical activity medicine is discussed. Physical activity as a therapy now exists to prevent most of the chronic diseases. The future needs to understand the molecular basis for how the body becomes dysfunctional when its level of physical activity does not match the norm of physical activity that selected our inherited genome. [source] CPA assessment , the regional assessors' experienceCYTOPATHOLOGY, Issue 2007E. Welsh Many individuals within Laboratory Medicine will be unaware that CPA conducts assessments to two different sets of CPA Standards. There are the Standards for the Medical Laboratory and the Standards for EQA Schemes in Laboratory Medicine. The style and format of both sets of standards is very similar with each being presented in eight sections A , H. The EQA standards are almost identical to the laboratory standards with the exception of the E.F and G standards which are specific to EQA schemes. There are approximately 40 EQA Schemes registered with CPA compared with almost 2 500 laboratories. These EQA schemes vary from very large national/international schemes with numerous analytes to small interpretive schemes run by one individual with a personal interest in that specific subject. The large schemes usually come under the UKNEQAS consortia banner and due to their size and configuration do not present undue problems in the assessment process. Smaller interpretive EQA schemes present a challenge both for the scheme and CPA in gaining accreditation. These schemes are usually within the discipline of Histopathology and are regarded as educational rather than proficiency testing schemes. Very frequently, the scheme is organized by a single individual with a collection of microscope slides, storage facilities for the slides and a computer. This presents the Scheme Organizer with great difficulty in complying with the Quality Management System requirements of the CPA Standards. There are a number of models which can be applied in order to satisfy the requirement of the Quality Management System, but ultimately it must be recognized that in some circumstances it is not possible to accredit these small schemes. The NHSCSP Gynae Cytology EQA Scheme is probably the largest EQA scheme within the UK, in respect of the number of participants and the number of staff supporting the scheme. Scheme Management decided that all nine regions of England would apply for accreditation under one CPA Reference Number. This process meant that the scheme would be assessed as a Managed Pathology Network. This is unique in terms of EQA schemes and presented a number of problems not previously encountered in EQA scheme accreditation. This decision meant that all nine regions must comply with a single Quality Management System and other CPA standards whilst allowing flexibility within the system for each region to facilitate the assessment process specific to their user's requirements. The process worked in a satisfactory manner and the overall outcome was not dissimilar to that of other large EQA schemes. The assessment to the current EQA Standards only commenced in April 2006 whilst the Standards for Medical Laboratories commenced in 2003, and it is perhaps not surprising to find that the principal non-conformities are related to the Quality Management System. This parallels the findings encountered in laboratory accreditation. There is an ongoing educational process for Scheme Management and the Facilitators in each region in how to comply fully with the standards and a commitment to quality improvement which ultimately is beneficial to the participant's of the scheme and to patient safety. [source] Do past experience and competitive ability influence foraging strategies of parasitoids under interspecific competition?ECOLOGICAL ENTOMOLOGY, Issue 6 2008CECILE LE LANN Abstract 1.,In solitary parasitoids, several species can exploit the same host patch and competition could potentially be a strong selective agent as only one individual can emerge from a host. In cereal crops, Aphidius rhopalosiphi and A. ervi share the grain aphid Sitobion avenae as host. 2.,The present work studied foraging strategies of both species on patches already exploited by the other species. The study analysed larval competition in multi-parasitised hosts and compared the foraging behaviour of females with and without previous experience. 3.,It was found that A. ervi wins larval competition three times more often than A. rhopalosiphi. Both species spent less time on patches exploited by a heterospecific than on unexploited ones. When they foraged on heterospecifically exploited patches, experienced females induced less mortality in aphids than inexperienced ones. 4.,Although A. rhopalosiphi is a specialist on cereal aphids and is the most abundant species due to its early appearance in the season, S. avenae is still a profitable host for A. ervi, because: (i) A. rhopalosiphi leaves patches partially exploited, (ii) A. ervi wins larval competition in three out of four multi-parasitised hosts, and (iii) A. ervi is only slightly deterred by the cornicular secretions of the host and can thus easily parasitise hosts. [source] Setting the absolute tempo of biodiversity dynamicsECOLOGY LETTERS, Issue 7 2007Andrew P. Allen Abstract Neutral biodiversity theory has the potential to contribute to our understanding of how macroevolutionary dynamics influence contemporary biodiversity, but there are issues regarding its dynamical predictions that must first be resolved. Here we address these issues by extending the theory in two ways using a novel analytical approach: (1) we set the absolute tempo of biodiversity dynamics by explicitly incorporating population-level stochasticity in abundance; (2) we allow new species to arise with more than one individual. Setting the absolute tempo yields quantitative predictions on biodiversity dynamics that can be tested using contemporary and fossil data. Allowing incipient-species abundances greater than one individual yields predictions on how these dynamics, and the form of the species-abundance distribution, are affected by multiple speciation modes. We apply this new model to contemporary and fossil data that encompass 30 Myr of macroevolution for planktonic foraminifera. By synthesizing the model with these empirical data, we present evidence that dynamical issues with neutral biodiversity theory may be resolved by incorporating the effects of environmental stochasticity and incipient-species abundance on biodiversity dynamics. [source] DNA damage and repair measurements from cryopreserved lymphocytes without cell culture,A reproducible assay for intervention studiesENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 7 2006Jyh-Lurn Chang Abstract Single-cell gel electrophoresis (the Comet assay) can be used to measure DNA damage and DNA repair capacity (DRC). However, to test DRC of cryopreserved lymphocytes, published methods include steps for cell culturing and phytohemagglutinin stimulation, which may limit use of this assay in intervention studies. We developed a modified Comet assay protocol that allows us to measure DRC from cryopreserved lymphocytes without these in vitro manipulations. Assay reproducibility was evaluated by performing the assay six times on different dates using six aliquots from one blood draw of one individual. The interindividual variation was assessed by performing the assay using one aliquot from six individuals. When ,-irradiation was used as the mutagen, intra-assay coefficients of variation (CVs.) for baseline DNA damage, damage after ,-irradiation exposure, and DRC,measured as tail moment,were 8, 31, and 10%, respectively. Interindividual CVs. were higher. When H2O2 was used as the mutagen, intra-assay CVs. for damage measurements were lower for a protocol modification that included damage and repair at 37°C (CVs. ranging from 8 to 35%) than for the more standard 4°C protocol. Analyzing moment arm,the average distance of DNA migration within the tail,yielded similar results. DNA repair was successfully detected in each experiment. Comparing freshly isolated lymphocytes to cryopreserved lymphocytes from the same individuals' blood draw indicated that DRC was highly correlated when determined using moment arm values. This modified protocol extends the use of the Comet assay to measuring DRC in intervention studies (e.g., dietary interventions) in that it assesses cellular response after cryopreservation without cell culture or other extensive manipulation. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source] Functional trait variation and sampling strategies in species-rich plant communitiesFUNCTIONAL ECOLOGY, Issue 1 2010Christopher Baraloto Summary 1. ,Despite considerable interest in the application of plant functional traits to questions of community assembly and ecosystem structure and function, there is no consensus on the appropriateness of sampling designs to obtain plot-level estimates in diverse plant communities. 2. ,We measured 10 plant functional traits describing leaf and stem morphology and ecophysiology for all trees in nine 1-ha plots in terra firme lowland tropical rain forests of French Guiana (N = 4709). 3. ,We calculated, by simulation, the mean and variance in trait values for each plot and each trait expected under seven sampling methods and a range of sampling intensities. Simulated sampling methods included a variety of spatial designs, as well as the application of existing data base values to all individuals of a given species. 4. ,For each trait in each plot, we defined a performance index for each sampling design as the proportion of resampling events that resulted in observed means within 5% of the true plot mean, and observed variance within 20% of the true plot variance. 5. ,The relative performance of sampling designs was consistent for estimations of means and variances. Data base use had consistently poor performance for most traits across all plots, whereas sampling one individual per species per plot resulted in relatively high performance. We found few differences among different spatial sampling strategies; however, for a given strategy, increased intensity of sampling resulted in markedly improved accuracy in estimates of trait mean and variance. 6. ,We also calculated the financial cost of each sampling design based on data from our ,every individual per plot' strategy and estimated the sampling and botanical effort required. The relative performance of designs was strongly positively correlated with relative financial cost, suggesting that sampling investment returns are relatively constant. 7. ,Our results suggest that trait sampling for many objectives in species-rich plant communities may require the considerable effort of sampling at least one individual of each species in each plot, and that investment in complete sampling, though great, may be worthwhile for at least some traits. [source] Estimation of allele frequencies with data on sibshipsGENETIC EPIDEMIOLOGY, Issue 3 2001Karl W. Broman Abstract Allele frequencies are generally estimated with data on a set of unrelated individuals. In genetic studies of late-onset diseases, the founding individuals in pedigrees are often not available, and so one is confronted with the problem of estimating allele frequencies with data on related individuals. We focus on sibpairs and sibships, and compare the efficiency of four methods for estimating allele frequencies in this situation: (1) use the data for one individual from each sibship; (2) use the data for all individuals, ignoring their relationships; (3) use the data for all individuals, taking proper account of their relationships, considering a single marker at a time; and (4) use the data for all individuals, taking proper account of their relationships, considering a set of linked markers simultaneously. We derived the variance of estimator 2, and showed that the estimator is unbiased and provides substantial improvement over method 1. We used computer simulation to study the performance of methods 3 and 4, and showed that method 3 provides some improvement over method 2, while method 4 improves little on method 3. Genet. Epidemiol. 20:307,315, 2001. © 2001 Wiley-Liss, Inc. [source] Analysis of hepatitis B viral load decline under potent therapy: Complex decay profiles observedHEPATOLOGY, Issue 5 2001Sharon R. Lewin We used a new real-time polymerase chain reaction (PCR)-based assay that is sensitive, has a wide dynamic linear range, and is highly reproducible to quantify hepatitis B virus (HBV) DNA in the serum of infected individuals undergoing potent antiviral therapy. In addition, we made frequent measurements of viral load after initiation of treatment and maintained follow-up to about 12 weeks. To analyze the data we used a new model of HBV decay, which takes into account that existing drug treatments do not completely block de novo infection and the possibility of noncytolytic loss of infected cells. On initiation of therapy, there was a mean delay of 1.6 days followed by a biphasic or muliphasic decay of plasma HBV DNA. The slope of the first phase varied considerably, with one individual having rapid decay, corresponding to a virion half-life of 1 hour, but others showing half-lives of up to 92 hours. Individuals either had a slow second-phase decline (t½ = 7.2 ± 1.2 days) or a flat second phase. Some individuals exhibited a complex "staircase pattern" of decay, with further phases of viral DNA decline and phases with little change in viral load. [source] Chromosomal anomalies on 6p25 in iris hypoplasia and Axenfeld-Rieger syndrome patients defined on a purpose-built genomic microarray,HUMAN MUTATION, Issue 1 2004Rosemary Ekong Abstract In many inherited diseases, the same phenotype can be produced both by single-base changes and by large deletions, or in some cases by duplications. Routine high-throughput sequencing can now detect small mutations relatively easily in a diagnostic setting, but deletions and duplications in the 50,500-kb region remain a more difficult problem. We have explored the application of array-CGH to the detection of such changes on a set of 20 samples consisting of patients with eye diseases associated with changes on chromosome 6p25 together with unaffected individuals, as well as two samples from tuberous sclerosis 2 (TSC2)-affected patients. We developed a microarray consisting of degenerate oligonucleotide primer (DOP)-PCR products from 260 human genomic clones, including BACs, PACs, and cosmids. In a masked study, chromosome changes in patients with iris hypoplasia (duplication) and Axenfeld-Rieger syndrome (deletion) were unequivocally distinguished from controls. Of the 20 6p25 samples analyzed, 19 were analyzed correctly (10 duplication cases, two deletions, and seven normals), while one individual failed to give a result because of poor hybridization. The extent of the duplication or deletion estimated was similar to that obtained by independent and much more time-consuming FISH experiments. On the other hand, deletions in the two TSC2 -affected samples, previously mapped by DNA molecular combing, were not detected on the array, possibly due to the repeat content of that region. Excluding the 16p13 cosmids, consistent results were obtained from all other cosmid clones; the potential for producing affordable disease-specific diagnostic microarray as an adjunct to diagnosis is discussed. Hum Mutat 24:76,85, 2004. © 2004 Wiley-Liss, Inc. [source] Follicle-stimulating hormone and oestradiol levels during perimenopause in a cohort of Japanese womenINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 10 2008M. Yamada Summary Context:, There had been a lack of longitudinal studies regarding follicle-stimulating hormone (FSH) and oestradiol (E2) during perimenopause for non-Caucasian populations. Objective:, To investigate FSH and E2 levels during perimenopause in a Japanese cohort. Design and setting:, The Adult Health Study is a longitudinal population-based study. Perimenopausal women from this study cohort were followed between 1993 and 2003. Participants and main outcome measures:, Non-menopausal women, aged 47,54 years, were measured in terms of FSH and E2 levels every 6 months. For 89 women whose FSH and E2 levels were measured within 3 months from their final menstrual period (FMP), trends of FSH and E2 within 21 months of FMP were investigated at 6-month intervals. Results:, Follicle-stimulating hormone and E2 levels within 3 months from FMP showed wide ranges. Neither FSH nor E2 levels differed by age, weight or duration of amenorrhoea. Although FSH increased and E2 decreased during perimenopause, FSH and E2 levels at a single time point were found to not be a reliable marker of biological menopause, as hormone levels in and between the subjects showed wide variation and any trend in one individual was not necessarily one directional. Conclusions:, Among Japanese women who had natural menopause around the age of 50, hormone levels in and between individuals showed wide variation throughout perimenopause with a converged biochemical menopausal pattern characterised by high FSH and low E2 at about 2 years after FMP. [source] SCN5A Mutation Associated with Cardiac Conduction Defect and Atrial ArrhythmiasJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2006PÄIVI J. LAITINEN-FORSBLOM Ph.D. Introduction: We aimed at identifying the molecular defect underlying the clinical phenotype of a Finnish family with a cardiac conduction defect and atrial arrhythmias. Methods and Results: A large Finnish family was clinically evaluated (ECG, 24-hour ambulatory ECG, echocardiography). We performed linkage analysis with markers flanking the SCN5A gene and subsequently sequenced the SCN5A gene. Five family members had atrial arrhythmias and intracardiac conduction defects, and due to bradycardia needed a pacemaker when adolescents. No heart failure or sudden cardiac death was observed. Left ventricle dilatation was seen in one individual and three individuals had a slightly enlarged right ventricle. Premature death due to stroke occurred in one subject during the study, and two other members had suffered from stroke at young age. Linkage analysis favored the role of the SCN5A gene in disease pathogenesis, and direct sequencing disclosed D1275N mutation. This alteration was present not only in all six affected individuals, but also in two young individuals lacking clinical symptoms. Conclusions: Cardiac conduction defect and atrial arrhythmias in a large Finnish family appear to result from the SCN5A D1275N mutation. Although no sudden cardiac death was recorded in the family, at least three affected members had encountered brain infarction at the age of 30 or younger. [source] Differentiation of morphology, genetics and electric signals in a region of sympatry between sister species of African electric fish (Mormyridae)JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2008S. LAVOUÉ Abstract Mormyrid fishes produce and sense weak electric organ discharges (EODs) for object detection and communication, and they have been increasingly recognized as useful model organisms for studying signal evolution and speciation. EOD waveform variation can provide important clues to sympatric species boundaries between otherwise similar or morphologically cryptic forms. Endemic to the watersheds of Gabon (Central Africa), Ivindomyrus marchei and Ivindomyrus opdenboschi are morphologically similar to one another. Using morphometric, electrophysiological and molecular characters [cytochrome b sequences and amplified fragment length polymorphism (AFLP) genotypes], we investigated to what extent these nominal mormyrid species have diverged into biological species. Our sampling covered the known distribution of each species with a focus on the Ivindo River, where the two taxa co-occur. An overall pattern of congruence among datasets suggests that I. opdenboschi and I. marchei are mostly distinct. Electric signal analysis showed that EODs of I. opdenboschi tend to have a smaller initial head-positive peak than those of I. marchei, and they often possess a small third waveform peak that is typically absent in EODs of I. marchei. Analysis of sympatric I. opdenboschi and I. marchei populations revealed slight, but significant, genetic partitioning between populations based on AFLP data (FST , 0.04). Taken separately, however, none of the characters we evaluated allowed us to discriminate two completely distinct or monophyletic groups. Lack of robust separation on the basis of any single character set may be a consequence of incomplete lineage sorting due to recent ancestry and/or introgressive hybridization. Incongruence between genetic datasets in one individual, which exhibited a mitochondrial haplotype characteristic of I. marchei but nevertheless fell within a genetic cluster of I. opdenboschi based on AFLP genotypes, suggests that a low level of recent hybridization may also be contributing to patterns of character variation in sympatry. Nevertheless, despite less than perfect separability based on any one dataset and inconclusive evidence for complete reproductive isolation between them in the Ivindo River, we find sufficient evidence to support the existence of two distinctive species, I. opdenboschi and I. marchei, even if not ,biological species' in the Mayrian sense. [source] The relative lengths of individual telomeres are defined in the zygote and strictly maintained during lifeAGING CELL, Issue 3 2004Jesper Graakjaer Summary Previous studies have indicated that average telomere length is partly inherited (Slagboom et al., 1994; Rufer et al., 1999) and that there is an inherited telomere pattern in each cell (Graakjaer et al., 2003); (Londoño-Vallejo et al., 2001). In this study, we quantify the importance of the initially inherited telomere lengths within cells, in relation to other factors that influence telomere length during life. We have estimated the inheritance by measuring telomere length in monozygotic (MZ) twins using Q-FISH with a telomere specific peptide nucleic acid (PNA)-probe. Homologous chromosomes were identified using subtelomeric polymorphic markers. We found that identical homologous telomeres from two aged MZ twins show significantly less differences in relative telomere length than when comparing the two homologues within one individual. This result means that towards the end of life, individual telomeres retain the characteristic relative length they had at the outset of life and that any length alteration during the lifespan impacts equally on genetically identical homologues. As the result applies across independent individuals, we conclude that, at least in lymphocytes, epigenetic/environmental effects on relative telomere length are relatively minor during life. [source] Heteroplasmy in Hair: Study of Mitochondrial DNA Third Hypervariable Region in Hair and Blood Samples,JOURNAL OF FORENSIC SCIENCES, Issue 3 2010Greiciane G. Paneto M.Sc. Abstract:, Mitochondrial DNA (mtDNA) analysis has proved useful for forensic identification especially in cases where nuclear DNA is not available, such as with hair evidence. Heteroplasmy, the presence of more than one type of mtDNA in one individual, is a common situation often reported in the first and second mtDNA hypervariable regions (HV1/HV2), particularly in hair samples. However, there is no data about heteroplasmy frequency in the third mtDNA hypervariable region (HV3). To investigate possible heteroplasmy hotspots, HV3 from hair and blood samples of 100 individuals were sequenced and compared. No point heteroplasmy was observed, but length heteroplasmy was, both in C-stretch and CA repeat. To observe which CA "alleles" were present in each tissue, PCR products were cloned and re-sequenced. However, no variation among CA alleles was observed. Regarding forensic practice, we conclude that point heteroplasmy in HV3 is not as frequent as in the HV1/HV2. [source] The Response of Skin to Applied Stress: Investigation of Bitemark Distortion in a Cadaver Model,JOURNAL OF FORENSIC SCIENCES, Issue 1 2010Mary A. Bush D.D.S. Abstract:, Knowledge of distortional properties of skin is important in bitemark analysis. Thus, the response of skin to stress from bites was investigated. Four sets of models were created from the dentition of one individual. Anterior teeth were systematically removed to vary contact surface area. A biting apparatus was constructed with an integrated load cell. Forty-six bites were created perpendicular to Langer lines on six cadavers. Rate of force application and bite pressure were controlled. Metric/angular measurement and hollow volume overlays were employed. Distortion produced by each dentition was calculated and assessed. Results showed that as teeth impressed loose tissue, mesial/distal distance increased, angles of rotation flattened, and inter-canine distance lengthened. An opposite effect was seen in tight tissue. When the surface area of the dentition was reduced, a mixture of these effects was observed. Conclusions indicated that stiffness of the tissue was the most important variable in bitemark distortion. [source] The use of a linkage analysis as evidence in the conviction of the Newcastle serial murderer, South AfricaJOURNAL OF INVESTIGATIVE PSYCHOLOGY AND OFFENDER PROFILING, Issue 3 2006Gérard N. Labuschagne Abstract The linking of a series of crimes to one individual has always been problematic, especially in the absence of eyewitness or forensic evidence. During the investigation, another means whereby this can be done is through linkage analysis. Yet a linkage analysis can also play a role during the trial of a serial offender. This paper examines the use of a linkage analysis report as evidence during the trial of the Newcastle serial murderer in South Africa. The linkage analysis examined the circumstances of the crime, modus operandi, and signature behaviour of the offender, to come to the conclusion that all the offences were committed by one individual, despite the lack of eyewitness or forensic evidence linking the suspect to two of the four incidents. This evidence was admitted by the court and the presiding officer concurred that the accused was guilty of committing the crimes during the third and fourth incidents. Copyright © 2006 John Wiley & Sons, Ltd. [source] Genotyping of the JC virus in urine samples of healthy Korean individualsJOURNAL OF MEDICAL VIROLOGY, Issue 2 2004Byung-Hoon Jeong Abstract A human polyomavirus, JC virus (JCV) is ubiquitous in humans and infects children asymptomatically. It persists in renal tissue and is excreted progeny in urine. DNAs from urine samples of 100 healthy Korean individuals were screened for the presence of JCV by polymerase chain reaction (PCR). Twenty of the samples were positive for JCV. JCV DNA was found in one individual (4%) in the 1,19-year group, two individuals (9%) in the 20,39-year group, ten individuals (38%) in the 40,59-year group, seven individuals (28%) in the over 60-year group. The prevalence of JC viral DNA was the highest in the 40,59-year-old Korean population. To investigate genotypes of JCV in Korea, the genotypes were determined by DNA sequence analysis of the regulatory region (333 bp) and the VT-intergenic region (656 bp) of DNA from the 20 JCV isolates. We have identified three distinctive JCV strains in the regulatory region and ten distinctive JCV strains in the VT-intergenic region of DNA from the 20 isolates. Based on restriction fragment length polymorphism (RFLP) analysis and phylogenetic analysis of the VT-intergenic region of JCV, two distinct subtypes, CY and type 2A (MY), were found to be prevalent in this Korean population. CY and type 2A of JCV were identified in 13 individuals (65%) and four individuals (20%), respectively. Interestingly, type 1, which was distributed mostly in Europe, was found in 3 (15%) isolates from healthy Korean individuals. J. Med. Virol. 72:281,289, 2004. © 2004 Wiley-Liss, Inc. [source] Variation in enterovirus receptor genesJOURNAL OF MEDICAL VIROLOGY, Issue 1 2003Åse Karttunen Abstract The increased incidence of a enterovirus infections observed in patients with type 1 diabetes preceding the development of the clinical disease could be partially explained by variation in the genes coding for enterovirus receptors. We carried out sequence analysis of the most common enterovirus receptor molecules in 21 diabetic children and 20 healthy adults. DNA was isolated from the leukocytes, and gene regions known to code for virus-recognizing domains in major enterovirus receptors were amplified and sequenced. Heterozygous single-nucleotide polymorphism (SNP), Ala 67 (GCG),,,Thr (ACG), was detected in the poliovirus receptor gene in four individuals in the diabetes group, but not in the control group. However, serological studies could not confirm that this substitution would convey different susceptibility to poliovirus infection. A heterozygous SNP, Lys 29 (AAG),,,Met (ATG), was found in the intracellular adhesion molecule-1 (ICAM-1) (receptor for rhinoviruses and some coxsackie A viruses) in one individual in both groups. A silent SNP in the ,2 integrin subunit gene (echovirus 1 receptor) was frequently found in both groups, a silent heterozygotic SNP in coxsackievirus-adenovirus receptor (coxsackie B virus receptor) gene was seen in one individual in the diabetes group, whereas no variation was found in the DAF (echovirus receptor) and ,3 integrin subunit sequences (receptor for coxsackievirus A9) studied. In conclusion, both synonymous and nonsynonymous sequence variability of genes coding for enterovirus and rhinovirus receptors was shown to occur, but no pattern directly specific for type 1 diabetes was found. J. Med. Virol. 70:99,108, 2003. © 2003 Wiley-Liss, Inc. [source] Spatial ecology of the mulgara in arid Australia: impact of fire history on home range size and burrow useJOURNAL OF ZOOLOGY, Issue 4 2007G. Körtner Abstract Knowledge about the spatial ecology of small mammals in relation to fire history in arid zones in general and Australia in particular is limited. Here, we report data on the spatial ecology of the brush-tailed mulgara Dasycercus blythi in the hummock grasslands of Uluru , Kata Tjuta National Park during winter 2006, the beginning of the breeding season for this species. About 73% of the study area had been burnt in 2002 and spinifex cover was sparse. Mulgaras Marsupialia: Dasyuridae (six males and three females) were implanted with radio-transmitters and monitored daily for between 6 and 55 days. All mulgaras appeared to use defined home ranges, which overlapped extensively with those of several neighbours. Spatial overlap occurred between as well as within sexes. On average, males (25.5 ha) occupied significantly larger home ranges than females (10.8 ha). Mulgaras used a number of burrows within home ranges and several were used by more than one individual. Moreover, occasionally, two individuals used the same burrow simultaneously. Home ranges and burrows encompassed both mature spinifex Triodia basedowii and open regrowth areas and mulgaras did not exhibit a significant preference for either habitat type. However, three males were killed by introduced-predators and they all lived predominantly in the open regrowth area. We conclude that mulgaras do not select the dense cover of mature spinifex habitat, and might be subjected to increased risk from introduced predators, especially following fire. [source] Host selection by Anopheles arabiensis and An. quadriannulatus feeding on cattle in ZimbabweMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2002A. Prior Abstract In the Zambezi valley, mosquito females of the Anopheles gambiae Giles complex (Diptera: Culicidae) were collected from a hut containing pairs of cattle distinguishable by known DNA markers. DNA was extracted from the blood-fed mosquito abdomens and primer sets for ungulate and mosquito DNA loci were used to identify the mosquito sibling species and individual host source(s) of their bloodmeals. The 67 mosquitoes comprised a mixture of An. arabiensis Patton (31%) and An. quadriannulatus Theobald (69%). DNA from one or both of the cattle present in the hut was detected in 91% of samples. When the hut contained an adult and a calf, the percentage of bloodmeals from the adult, the calf and adult + calf were 58%, 27% and 15%, respectively; the trend towards meals from the adult host was consistent but not always significant. When the pair of cattle comprised two adults of roughly equal size and age, then mosquitoes generally showed no significant bias towards feeding from one individual. There was no significant difference in the pattern of host selection made by An. arabiensis and An. quadriannulatus but the former had a significantly higher percentage (20%) of mixed meals than An. quadriannulatus (9%). These two members of the An. gambiae complex appear to be less selective in their choice of cattle hosts compared to day-active Diptera such as tsetse and Stomoxys, possibly because the hosts are generally asleep when Anopheles are active and there is therefore less selective pressure to adapt to host defensive behaviour. The slight bias of Anopheles towards older and/or larger cattle may be related to the host's larger surface area. [source] Genetic variation in Holocene bowhead whales from SvalbardMOLECULAR ECOLOGY, Issue 11 2007T. BORGE Abstract Bowhead whales (Balaena mysticetus) are distributed in the Arctic in five putative stocks. All stocks have been heavily depleted due to centuries of exploitation. In the present study, nucleotide sequence variation of the mitochondrial control region was determined from bone remains of 99 bowhead whales. The bones, 14C dated from recent to more than 50 000 bp, were collected on Svalbard (Spitsbergen) and are expected to relate to ancestors of the today nearly extinct Spitsbergen stock. Fifty-eight haplotypes were found, a few being frequent but many only found in one individual. The most abundant haplotypes of the Spitsbergen stock are the same as those most abundant in the extant Bering-Chukchi-Beaufort (BCB) Seas stock of bowhead whales. Although FST indicates a slight but statistically significant genetic differentiation between the Spitsbergen and the BCB stocks this was not considered informative due to the very high levels of genetic diversity of mitochondrial DNA haplotypes in both bowhead whale stocks. Other measures such as KST also indicated very low genetic differentiation between the two populations. Nucleotide diversity and haplotype diversity showed only minor differences between the Spitsbergen and BCB stocks. The data suggest that the historic Spitsbergen stock , before the severe bottleneck caused by whaling , did not have substantially more genetic variation than the extant BCB stock. The similar haplotypes of the Holocene Svalbard samples and the current BCB stock indicate significant migration between these two stocks and question the current designation of five distinct stocks of bowhead whales in the Arctic. [source] Patterns of variation at a mitochondrial sequence-tagged-site locus provides new insights into the postglacial history of European Pinus sylvestris populationsMOLECULAR ECOLOGY, Issue 9 2000N. Soranzo Abstract Due to their maternal mode of inheritance, mitochondrial markers can be regarded as almost ,ideal' tools in evolutionary studies of conifer populations. In the present study, polymorphism was analysed at one mitochondrial intron (nad 1, exon B/C) in 23 native European Pinus sylvestris populations. In a preliminary screening for variation using a polymerase chain reaction,restriction fragment length polymorphism approach, two length variants were identified. By fully sequencing the 2.5 kb region, the observed length polymorphism was found to result from the insertion of a 31 bp sequence, with no other mutations observed within the intron. A set of primers was designed flanking the observed mutation, which identified a novel sequence-tagged-site mitochondrial marker for P. sylvestris. Analysis of 747 trees from the 23 populations using these primers revealed the occurrence of two distinct haplotypes in Europe. Within the Iberian Peninsula, the two haplotypes exhibited extensive population differentiation (,ST = 0.59; P , 0.001) and a marked geographical structuring. In the populations of central and northern Europe, one haplotype largely predominated, with the second being found in only one individual of one population. [source] Rare species in communities of tropical insect herbivores: pondering the mystery of singletonsOIKOS, Issue 3 2000Vojtech Novotný The host specificity, taxonomic composition and feeding guild of rare species were studied in communities of herbivorous insects in New Guinea. Leaf-chewing and sap-sucking insects (Orthoptera, Phasmatodea, Coleoptera, Lepidoptera and Hemiptera-Auchenorrhyncha) were sampled from 30 species of trees and shrubs (15 spp. of Ficus, Moraceae, six spp. of Macaranga and nine species of other Euphorbiaceae) in a lowland rain forest. Feeding trials were performed with all leaf-chewers in order to exclude transient species. Overall, the sampling produced 80,062 individuals of 1050 species. The species accumulation curve did not attain an asymptote, despite 950 person-days of sampling. Rare species, defined as those found as single individuals, remained numerous even in large samples and after the exclusion of transient, non-feeding species. There was no difference among plant species in the proportion of rare species in their herbivore communities, which was, on average, 45%. Likewise, various herbivore guilds and taxa had all very similar proportions of rare and common species. There was also no difference between rare and common species in their host specificity. Both highly specialised species and generalists, feeding on numerous plants, contributed to the singleton records on particular plant species. Predominantly, a species was rare on a particular host whilst more common on other, often related, host species, or relatively rare on numerous other host plants, so that its aggregate population was high. Both cases are an example of the "mass effect", since it is probable that such rare species were dependent on a constant influx of immigrants from the other host plants. These other plants were found particularly often among congeneric plants, less so among confamilial plants from different genera and least frequently among plants from different families. There were also 278 very rare species, found as one individual on a single plant species only. Their host specificity could not be assessed; they might have been either very rare specialists, or species feeding also on other plants, those that were not studied. The former possibility is unlikely since monophagous species, collected as singletons at the present sampling effort, would have existed at an extremely low population density, less than 1 individual per 10 ha of the forest. [source] Investigating cultural heterogeneity in San Pedro de Atacama, northern Chile, through biogeochemistry and bioarchaeologyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009Kelly J. Knudson Abstract Individuals living in the San Pedro de Atacama oases and the neighboring upper Loa River Valley of northern Chile experienced the collapse of an influential foreign polity, environmental decline, and the appearance of a culturally distinct group during the Late Intermediate Period (ca. AD 1,100,1,400). We investigate cultural heterogeneity at the Loa site of Caspana through analyses of strontium and oxygen isotopes, cranial modification styles, and mortuary behavior, integrating biological aspects of identity, particularly geographic origins, with cultural aspects of identity manifested in body modification and mortuary behavior. We test the hypothesis that the Caspana population (n = 66) represents a migrant group, as supported by archeological and ethnographic evidence, rather than a culturally distinct local group. For Caspana archeological human tooth enamel, mean 87Sr/86Sr = 0.70771 ± 0.00038 (1,, n = 30) and mean ,18Oc(V-PDB) = ,3.9 ± 0.6, (1,, n = 16); these isotopic data suggest that only one individual lived outside the region. Material culture suggests that the individuals buried at Caspana shared some cultural affinity with the San Pedro oases while maintaining distinct cultural traditions. Finally, cranial modification data show high frequencies of head shaping [92.4% (n = 61/65)] and an overwhelming preference for annular modification [75.4% (n = 46/61)], contrasting sharply with practices in the San Pedro area. Based on multiple lines of evidence, we argue that, rather than representing a group of altiplano migrants, the Caspana population existed in the region for some time. However, cranial modification styles and mortuary behavior that are markedly distinct from patterns in surrounding areas raise the possibility of cultural heterogeneity and cultural fissioning. Am J Phys Anthropol, 2009. © 2008 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||