Apparent survival of the salamander

Background Understanding the demographic processes underlying population dynamics is a central theme in ecology. Populations decline if losses from the population (i.e., mortality and emigration) exceed gains (i.e., recruitment and immigration). Amphibians are thought to exhibit little movement even though local populations often fluctuate dramatically and are likely to go exinct if there is no rescue effect through immigration from nearby populations. Terrestrial salamanders are generally portrayed as amphibians with low migratory activity. Our study uses demographic analysis as a key to unravel whether emigration or mortality is the main cause of "losses" from the population. In particular, we use the analysis to challenge the common belief that terrestrial salamanders show low migratory activity. Results The mark-recapture analysis of adult salamanders showed that monthly survival was high (> 90%) without a seasonal pattern. These estimates, however, translate into rather low rates of local annual survival of only ~40% and suggest that emigration was important. The estimated probability of emigration was 49%. Conclusion Our analysis shows that terrestrial salamanders exhibit more migratory activity than commonly thought. This may be due either because the spatial extent of salamander populations is underestimated or because there is a substantial exchange of individuals between populations. Our current results are in line with several other studies that suggest high migratory activity in amphibians. In particular, many amphibian populations may be characterized by high proportions of transients and/or floaters.

Genetic variation and demographic history of the Haplochromis laparogramma group of Lake Victoria-An analysis based on SINEs and mitochondrial DNA

More than 500 endemic haplochromine cichlid species inhabit Lake Victoria. This striking species diversity is a classical example of recent explosive adaptive radiation thought to have happened within the last similar to 15,000 years. In this study, we examined the population structure and historical demography of 3 pelagic haplochromine cichlid species that resemble in morphology and have similar niche, Haplochromis (Yssichromis) laparogramma, Haplochromis (Y.) pyrrhocephalus, and Haplochromis (Y.) sp. "glaucocephalus". We investigated the sequences of the mitochondrial DNA control region and the insertion patterns of short interspersed elements (SINEs) of 759 individuals. We show that sympatric forms are genetically differentiated in 4 of 6 cases, but we also found apparent weakening of the genetic differentiation in areas with turbid water. We estimated the timings of population expansion and species divergence to coincide with the refilling of the lake at the Pleistocene/Holocene boundary. We also found that estimates can be altered significantly by the choice of the shape of the molecular clock. If we employ the nonlinear clock model of evolutionary rates in which the rates are higher towards the recent, the population expansion was dated at around the event of desiccation of the lake ca. 17,000 YBP. Thus, we succeeded in clarifying the species and population structure of closely related Lake Victoria cichlids and in showing the importance of applying appropriate clock calibrations in elucidating recent evolutionary events. (C) 2009 Elsevier B.V. All rights reserved.

Antiretroviral therapy during pregnancy and premature birth: analysis of Swiss data

Background There is an ongoing debate as to whether combined antiretroviral treatment (cART) during pregnancy is an independent risk factor for prematurity in HIV-1-infected women. Objective The aim of the study was to examine (1) crude effects of different ART regimens on prematurity, (2) the association between duration of cART and duration of pregnancy, and (3) the role of possibly confounding risk factors for prematurity. Method We analysed data from 1180 pregnancies prospectively collected by the Swiss Mother and Child HIV Cohort Study (MoCHiV) and the Swiss HIV Cohort Study (SHCS). Results Odds ratios for prematurity in women receiving mono/dual therapy and cART were 1.8 [95% confidence interval (CI) 0.85–3.6] and 2.5 (95% CI 1.4–4.3) compared with women not receiving ART during pregnancy (P=0.004). In a subgroup of 365 pregnancies with comprehensive information on maternal clinical, demographic and lifestyle characteristics, there was no indication that maternal viral load, age, ethnicity or history of injecting drug use affected prematurity rates associated with the use of cART. Duration of cART before delivery was also not associated with duration of pregnancy. Conclusion Our study indicates that confounding by maternal risk factors or duration of cART exposure is not a likely explanation for the effects of ART on prematurity in HIV-1-infected women.

Prevalence and predictors of kaposi sarcoma herpes virus seropositivity: a cross-sectional analysis of HIV-infected adults initiating ART in Johannesburg, South Africa

Background Kaposi sarcoma (KS) is the most common AIDS-defining tumour in HIV-infected individuals in Africa. Kaposi sarcoma herpes virus (KSHV) infection precedes development of KS. KSHV co-infection may be associated with worse outcomes in HIV disease and elevated KSHV viral load may be an early marker for advanced HIV disease among untreated patients. We examined the prevalence of KSHV among adults initiating antiretroviral therapy (ART) and compared immunological, demographic and clinical factors between patients seropositive and seronegative for KSHV. Results We analyzed cross-sectional data collected from 404 HIV-infected treatment-naïve adults initiating ART at the Themba Lethu Clinic, Johannesburg, South Africa between November 2008 and March 2009. Subjects were screened at ART initiation for antibodies to KSHV lytic K8.1 and latent Orf73 antigens. Seropositivity to KSHV was defined as positive to either lytic KSHV K8.1 or latent KSHV Orf73 antibodies. KSHV viremia was determined by quantitative PCR and CD3, 4 and 8 lymphocyte counts were determined with flow cytometry. Of the 404 participants, 193 (48%) tested positive for KSHV at ART initiation; with 76 (39%) reactive to lytic K8.1, 35 (18%) to latent Orf73 and 82 (42%) to both. One individual presented with clinical KS at ART initiation. The KSHV infected group was similar to those without KSHV in terms of age, race, gender, ethnicity, smoking and alcohol use. KSHV infected individuals presented with slightly higher median CD3 (817 vs. 726 cells/mm3) and CD4 (90 vs. 80 cells/mm3) counts than KSHV negative subjects. We found no associations between KSHV seropositivity and body mass index, tuberculosis status, WHO stage, HIV RNA levels, full blood count or liver function tests at initiation. Those with detectable KSHV viremia (n = 19), however, appeared to present with signs of more advanced HIV disease including anemia and WHO stage 3 or 4 defining conditions compared to those in whom the virus was undetectable. Conclusions We demonstrate a high prevalence of KSHV among HIV-infected adults initiating ART in a large urban public-sector HIV clinic. KSHV viremia but not KSHV seropositivity may be associated with markers of advanced HIV disease.

Outcomes of antiretroviral therapy in the Swiss HIV Cohort Study: latent class analysis

An in-depth understanding of the different groups that make up the HIV-infected population should inform prevention and care. Using latent class analysis (LCA) we identified seven groups with similar socio-demographic and behavioral characteristics at enrolment in the Swiss HIV Cohort Study: older gay men, younger gay men, older heterosexual men, injection drug users, single migrants, migrant women in partnerships and heterosexual men and women. Outcomes of combination antiretroviral therapy (ART) were analyzed in 1,633 patients starting ART. Compared to older gay men, the probability of a virologic response to ART was reduced in single migrants, in older heterosexual men and in IDUs. Loss to follow-up was higher in single migrants and IDUs, and mortality was increased in older heterosexual men and IDUs. Socio-behavioral groups identified by LCA allow insights above what can be gleaned from traditional transmission groups, and may identify patients who could benefit from targeted interventions.

Temporal factors in violence related injuries--An 11 year trend analysis of violence-related injuries from a Swiss Emergency Department

Injury from interpersonal violence is a major social and medical problem in the industrialized world. Little is known about the trends in prevalence and injury pattern or about the demographic characteristics of the patients involved.

782 consecutive construction work accidents: who is at risk? A 10-year analysis from a Swiss university hospital trauma unit

BACKGROUND: Mortality and morbidity are particularly high in the building industry. The annual rate of non-fatal occupational accidents in Switzerland is 1,133 per 100,000 inhabitants. METHODS: Retrospective analysis of the electronic database of a university emergency centre. Between 2001 and 2011, 782 occupational accidents to construction workers were recorded and analysed using specific demographic and medical keywords. RESULTS: Most patients were aged 30-39 (30.4%). 66.4% of the injured workers were foreigners. This is almost twice as high as the overall proportion of foreigners in Switzerland or in the Swiss labour market. 16% of the Swiss construction workers and 8% of the foreign construction workers suffered a severe injury with ISS >15. There was a trend for workers aged 60 and above to suffer an accident with a high ISS (p = 0.089). CONCLUSIONS: As in other European countries, most patients were in their thirties. Older construction workers suffered fewer injuries, although these tended to be more severe. The injuries were evenly distributed through the working days of the week. A special effort should be made that current health and safety measures are understood and applied by foreign and older construction workers.

Hepatitis C in a sample of pregnant women in Switzerland: seroprevalence and socio-demographic factors

PRINCIPLES: The aim of this study was to determine the prevalence of hepatitis C (HCV) infection in a sample of pregnant women living in Switzerland in 1990-1991, in order to complement existing data in various populations. METHODS: Blood samples were collected from women from consecutive births in obstetric wards in public hospitals of 23 Swiss cantons over a one-year period. They were tested, among other things, for the presence of hepatitis C virus antibodies (anti-HCV). Statistical analyses were done to explore the association of demographic variables with anti-HCV. RESULTS: The study included a total of 9,057 women of whom 64 tested positive for anti-HCV, resulting in a crude prevalence of 0.71%. Prevalence varied by age and was highest in the 25-29-year age-group (0.90%). 43/5,685 Swiss women were HCV seropositive (0.76%) compared with 21/3,372 non-Swiss women (0.62%). Stratified analysis showed a significant association between anti-HCV and anti-HBc antibody positivity in Swiss (adjusted OR [aOR] 23, 95% CI 12-43) and non-Swiss nationals (aOR 3.3, 95% CI 1.3-8.3). CONCLUSIONS: The prevalence of anti-HCV antibodies in the early 1990s was <1% in this sample of pregnant women in Switzerland and was associated with age, nationality and the presence of anti-HBc antibodies, a marker of exposure to hepatitis B virus. These results are in accordance with those from other published European studies. If an effective intervention to prevent vertical transmission becomes available, information on the current prevalence of HCV in pregnant women would be needed in order to assess how screening recommendations should be modified.

Demographic characteristics of patients with extrapulmonary tuberculosis in Germany

The aim of the present study was to determine the demographics of patients with extrapulmonary tuberculosis in Germany. Data on 26,302 tuberculosis cases from a national survey carried out during the period 1996-2000 were analysed. The crude proportion of tuberculosis patients with extrapulmonary manifestations was 21.6%. Extrapulmonary tuberculosis was most likely among females, children aged <15 yrs and persons originating from Africa and Asia. Females tended to be more likely to have any form of extrapulmonary tuberculosis than males, except pleural tuberculosis. The strength of this association was strongest in the age range 25-64 yrs and less pronounced amongst the oldest patients. Children were particularly prone to the development of lymphatic and meningeal tuberculosis, whereas the likelihood of genitourinary tuberculosis increased with increasing age. Asian and African patients were generally more likely than persons from other areas to have lymphatic, osteoarticular, meningeal and miliary tuberculosis. The analysis shows important differences, by age, sex and origin, in the likelihood of a tuberculosis patient presenting with extrapulmonary tuberculosis. Since the relative contribution of the foreign-born to tuberculosis in low-prevalence countries is rising, extrapulmonary tuberculosis must be taken into account more often in the differential diagnostic work-up of these patients, particularly among those originating from Asia and Africa.

Hypereosinophilic syndrome: a multicenter, retrospective analysis of clinical characteristics and response to therapy

BACKGROUND: Hypereosinophilic syndrome (HES) is a heterogeneous group of rare disorders defined by persistent blood eosinophilia > or =1.5 x 10(9)/L, absence of a secondary cause, and evidence of eosinophil-associated pathology. With the exception of a recent multicenter trial of mepolizumab (anti-IL-5 mAb), published therapeutic experience has been restricted to case reports and small case series. OBJECTIVE: The purpose of the study was to collect and summarize baseline demographic, clinical, and laboratory characteristics in a large, diverse cohort of patients with HES and to review responses to treatment with conventional and novel therapies. METHODS: Clinical and laboratory data from 188 patients with HES, seen between January 2001 and December 2006 at 11 institutions in the United States and Europe, were collected retrospectively by chart review. RESULTS: Eighteen of 161 patients (11%) tested were Fip1-like 1-platelet-derived growth factor receptor alpha (FIP1L1-PDGFRA) mutation-positive, and 29 of 168 patients tested (17%) had a demonstrable aberrant or clonal T-cell population. Corticosteroid monotherapy induced complete or partial responses at 1 month in 85% (120/141) of patients with most remaining on maintenance doses (median, 10 mg prednisone equivalent daily for 2 months to 20 years). Hydroxyurea and IFN-alpha (used in 64 and 46 patients, respectively) were also effective, but their use was limited by toxicity. Imatinib (used in 68 patients) was more effective in patients with the FIP1L1-PDGFRA mutation (88%) than in those without (23%; P < .001). CONCLUSION: This study, the largest clinical analysis of patients with HES to date, not only provides useful information for clinicians but also should stimulate prospective trials to optimize treatment of HES.

Association of arterial blood pressure and vasopressor load with septic shock mortality: a post hoc analysis of a multicenter trial

INTRODUCTION: It is unclear to which level mean arterial blood pressure (MAP) should be increased during septic shock in order to improve outcome. In this study we investigated the association between MAP values of 70 mmHg or higher, vasopressor load, 28-day mortality and disease-related events in septic shock. METHODS: This is a post hoc analysis of data of the control group of a multicenter trial and includes 290 septic shock patients in whom a mean MAP > or = 70 mmHg could be maintained during shock. Demographic and clinical data, MAP, vasopressor requirements during the shock period, disease-related events and 28-day mortality were documented. Logistic regression models adjusted for the geographic region of the study center, age, presence of chronic arterial hypertension, simplified acute physiology score (SAPS) II and the mean vasopressor load during the shock period was calculated to investigate the association between MAP or MAP quartiles > or = 70 mmHg and mortality or the frequency and occurrence of disease-related events. RESULTS: There was no association between MAP or MAP quartiles and mortality or the occurrence of disease-related events. These associations were not influenced by age or pre-existent arterial hypertension (all P > 0.05). The mean vasopressor load was associated with mortality (relative risk (RR), 1.83; confidence interval (CI) 95%, 1.4-2.38; P < 0.001), the number of disease-related events (P < 0.001) and the occurrence of acute circulatory failure (RR, 1.64; CI 95%, 1.28-2.11; P < 0.001), metabolic acidosis (RR, 1.79; CI 95%, 1.38-2.32; P < 0.001), renal failure (RR, 1.49; CI 95%, 1.17-1.89; P = 0.001) and thrombocytopenia (RR, 1.33; CI 95%, 1.06-1.68; P = 0.01). CONCLUSIONS: MAP levels of 70 mmHg or higher do not appear to be associated with improved survival in septic shock. Elevating MAP >70 mmHg by augmenting vasopressor dosages may increase mortality. Future trials are needed to identify the lowest acceptable MAP level to ensure tissue perfusion and avoid unnecessary high catecholamine infusions.

Life expectancies of South African adults starting antiretroviral treatment: collaborative analysis of cohort studies

BACKGROUND Few estimates exist of the life expectancy of HIV-positive adults receiving antiretroviral treatment (ART) in low- and middle-income countries. We aimed to estimate the life expectancy of patients starting ART in South Africa and compare it with that of HIV-negative adults. METHODS AND FINDINGS Data were collected from six South African ART cohorts. Analysis was restricted to 37,740 HIV-positive adults starting ART for the first time. Estimates of mortality were obtained by linking patient records to the national population register. Relative survival models were used to estimate the excess mortality attributable to HIV by age, for different baseline CD4 categories and different durations. Non-HIV mortality was estimated using a South African demographic model. The average life expectancy of men starting ART varied between 27.6 y (95% CI: 25.2-30.2) at age 20 y and 10.1 y (95% CI: 9.3-10.8) at age 60 y, while estimates for women at the same ages were substantially higher, at 36.8 y (95% CI: 34.0-39.7) and 14.4 y (95% CI: 13.3-15.3), respectively. The life expectancy of a 20-y-old woman was 43.1 y (95% CI: 40.1-46.0) if her baseline CD4 count was ≥ 200 cells/µl, compared to 29.5 y (95% CI: 26.2-33.0) if her baseline CD4 count was <50 cells/µl. Life expectancies of patients with baseline CD4 counts ≥ 200 cells/µl were between 70% and 86% of those in HIV-negative adults of the same age and sex, and life expectancies were increased by 15%-20% in patients who had survived 2 y after starting ART. However, the analysis was limited by a lack of mortality data at longer durations. CONCLUSIONS South African HIV-positive adults can have a near-normal life expectancy, provided that they start ART before their CD4 count drops below 200 cells/µl. These findings demonstrate that the near-normal life expectancies of HIV-positive individuals receiving ART in high-income countries can apply to low- and middle-income countries as well. Please see later in the article for the Editors' Summary.

Children and adults with thrombotic thrombocytopenic purpura associated with severe, acquired Adamts13 deficiency: comparison of incidence, demographic and clinical features

BACKGROUND Thrombotic thrombocytopenic purpura (TTP) associated with severe, acquired ADAMTS13 deficiency is uncommonly reported in children. The incidence, demographic, and clinical features of these children, compared to adults, have not been described. PROCEDURES This study focused on children (<18 years old) and adults with TTP associated with severe, acquired ADAMTS13 deficiency, defined as activity <10%. The incidence rates for TTP in children and adults were calculated from patients enrolled in the Oklahoma TTP-HUS (Hemolytic-Uremic syndrome) Registry, 1996-2012. To describe demographic and clinical features, children with TTP were also identified from a systematic review of published reports and from samples sent to a reference laboratory for analysis of ADAMTS13. RESULTS The standardized annual incidence rate of TTP in children was 0.09 × 10(6) children per year, 3% of the incidence rate among adults (2.88 × 10(6) adults per year). Among the 79 children who were identified (one from the Oklahoma Registry, 55 from published reports, 23 from the reference laboratory), TTP appeared to be more common among females, similar to the relative increased frequency of women among adults with TTP, and more common in older children. Clinical data were available on 52 children; the frequency of severe renal failure, relapse, treatment with rituximab, and systemic lupus erythematosus in these children was similar to adults with TTP. CONCLUSIONS TTP associated with severe, acquired ADAMTS13 deficiency is uncommon in children. The demographic and clinical features of these children are similar to the features of adults with TTP.

Who is likely to develop persistent low back pain? A longitudinal analysis of prognostic occupational factors

OBJECTIVE: Occupational low back pain (LBP) is considered to be the most expensive form of work disability, with the socioeconomic costs of persistent LBP exceeding the costs of acute and subacute LBP by far. This makes the early identification of patients at risk of developing persistent LBP essential, especially in working populations. The aim of the study was to evaluate both risk factors (for the development of persistent LBP) and protective factors (preventing the development of persistent LBP) in the same cohort. PARTICIPANTS: An inception cohort of 315 patients with acute to subacute or with recurrent LBP was recruited from 14 health practitioners (twelve general practitioners and two physiotherapists) across New Zealand. METHODS: Patients with persistent LBP at six-month follow-up were compared to patients with non-persistent LBP looking at occupational, psychological, biomedical and demographic/lifestyle predictors at baseline using multiple logistic regression analyses. All significant variables from the different domains were combined into a one predictor model. RESULTS: A final two-predictor model with an overall predictive value of 78% included social support at work (OR 0.67; 95%CI 0.45 to 0.99) and somatization (OR 1.08; 95%CI 1.01 to 1.15). CONCLUSIONS: Social support at work should be considered as a resource preventing the development of persistent LBP whereas somatization should be considered as a risk factor for the development of persistent LBP. Further studies are needed to determine if addressing these factors in workplace interventions for patients suffering from acute, subacute or recurrent LBP prevents subsequent development of persistent LBP.