33 research outputs found
TEMPERATURE DEPENDENT DEVELOPMENT RATES OF PARASITOID, HABROBRACON HEBETOR, DIRECTLY FED ON BACILLUS THURINGIENSIS VAR. KURSTAKI
The interaction of temperature and directly ingested Bacillus thuringiensis (Bt), on the developmental rates of the parasitoid Habrobracon hebetor progeny was investigated using Corcyra cephalonica 4th instar larvae as host. Development rates increased with temperature rise. Regression analysis revealed highly significant (p <.01) good fit of the equation for incubation, larval and total lifecycle period, while significant (p <.05) for larval period in untreated diet fed H. hebetor, However, under the influence of Bt- honey diet, larval period (p >.05) was not a good fit of the equation. Although r- values were overall lower and regression showed no significant fit of the equation for larval periods, significantly higher development rate was observed towards higher temperatures. However, rates during pupal period and total lifecycle showed highly significant (p <.01) good fit of the equation. Significant interactions between Bt and temperature were observed during larval (F3,72= 45.443, p <.001) and pupal periods (F3,72= 3.932, p <.05), however, no such significant interaction occurred during incubation period (F3,72= 1.643, p= .187). Mean developmental rates during total life cycle also showed significant interaction between the factors, F3,72= 4.684, p <.01. Temperature was way more influential in all stages, as a factor (p < .001), than Bt. This study emphasizes the importance of temperature as an ecofactor during combined biological control. Interaction between higher temperatures and Bt, within the tolerance limit, may actually be beneficial through faster development during larval stage; although the same cannot be said of the other parameters of its life history
Genome-wide identification of Xenopus matrix metalloproteinases: conservation and unique duplications in amphibians
<p>Abstract</p> <p>Background</p> <p>Matrix metalloproteinases (MMPs) are members of the superfamily of Zn<sup>2+ </sup>dependent extracellular or membrane-bound endopeptidases which have been implicated to play critical roles in vertebrate development and human pathogenesis. A number of MMP genes have been found to be upregulated in some or all organs during frog metamorphosis, suggesting that different MMPs may have different functions in various organs/tissues. The recent advances in EST (expressed sequence tag) sequencing and the completion of the genome of <it>Xenopus (X.) tropicalis </it>prompted us to systematically analyze the existence of MMPs in the <it>Xenopus </it>genome.</p> <p>Results</p> <p>We examined <it>X. laevis </it>and <it>X. tropicalis </it>ESTs and genomic sequences for MMPs and obtained likely homologs for 20 out of the 25 MMPs known in higher vertebrates. Four of the five missing MMPs, i.e. MMPs 8, 10, 12 and 27, were all encoded on human Chromosome 11 and the other missing MMP, MMP22 (a chicken MMP), was also absent in human genome. In addition, we identified several novel MMPs which appears to be derived from unique duplications over evolution, are present in the genomes of both <it>Xenopus </it>species.</p> <p>Conclusion</p> <p>We identified the homologs of most of the mammalian MMPs in <it>Xenopus </it>and discovered a number of novel MMPs. Our results suggest that MMP genes undergo dynamic changes over evolution. It will be of interest in the future to investigate whether MMP expression and functions during vertebrate development are conserved. The sequence information reported here should facilitate such an endeavor in the near future.</p
Identification and Developmental Expression of Xenopus laevis SUMO Proteases
SUMO proteins are small ubiquitin-related modifiers. All SUMOs are synthesized as propeptides that are post-translationally cleaved prior to conjugation. After processing, SUMOs become covalently conjugated to cellular targets through a pathway that is similar to ubiquitination. Ubiquitin like protein proteases/Sentrin specific proteases (Ulp/SENPs) mediate both processing and deconjugation of SUMOs. The action of Ulp/SENPs makes SUMOylation a highly dynamic post-translational modification. To investigate how Ulp/SENPs are regulated in a developmental context, we isolated and characterized all Ulp/SENPs in Xenopus laevis. Xenopus possess homologues of mammalian SENP3, 5, 6 and 7. All of these enzymes reacted with HA-tagged vinyl sulfone derivatives of SUMO-2 (HA-SU2-VS) but not SUMO-1 (HA-SU1-VS), suggesting that they act primarily on SUMO-2 and -3. In contrast, Xenopus possess a single member of the SENP1/SENP2 subfamily of Ulp/SENPs, most closely related to mammalian SENP1. Xenopus SENP1 reacted with HA-SU1-VS and HA-SU2-VS, suggesting that it acts on all SUMO paralogues. We analyzed the mRNA and protein levels for each of the Ulp/SENPs through development; we found that they show distinct patterns of expression that may involve both transcriptional and post-transcriptional regulation. Finally, we have characterized the developmental function of the most abundant Ulp/SENP found within Xenopus eggs, SENP3. Depletion of SENP3 using morpholino antisense oligonucleotides (morpholinos) caused accumulation of high molecular weight SUMO-2/3 conjugated species, defects in developing embryos and changes in the expression of some genes regulated by the transforming growth factor beta (TGF-β) pathway. These findings collectively indicate that SUMO proteases are both highly regulated and essential for normal development
Effectiveness of a community-based intervention for people with schizophrenia and their caregivers in India (COPSI): a randomised controlled trial
Background: Observational evidence suggests that community-based services for people with schizophrenia can be successfully provided by community health workers, when supervised by specialists, in low-income and middleincome countries. We did the COmmunity care for People with Schizophrenia in India (COPSI) trial to compare the eff ectiveness of a collaborative community-based care intervention with standard facility-based care.
Methods: We did a multicentre, parallel-group, randomised controlled trial at three sites in India between Jan 1, 2009 and Dec 31, 2010. Patients aged 16–60 years with a primary diagnosis of schizophrenia according to the tenth edition of the International Classifi cation of Diseases, Diagnostic Criteria for Research (ICD-10-DCR) were randomly assigned (2:1), via a computer-generated randomisation list with block sizes of three, six, or nine, to receive either collaborative community-based care plus facility-based care or facility-based care alone. Randomisation was stratifi ed by study site. Outcome assessors were masked to group allocation. The primary outcome was a change in symptoms and disabilities over 12 months, as measured by the positive and negative syndrome scale (PANSS) and the Indian disability evaluation and assessment scale (IDEAS). Analysis was by modifi ed intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN 56877013.
Findings: 187 participants were randomised to the collaborative community-based care plus facility-based care group and 95 were randomised to the facility-based care alone group; 253 (90%) participants completed follow-up to month 12. At 12 months, total PANSS and IDEAS scores were lower in patients in the intervention group than in those in the control group (PANSS adjusted mean diff erence –3·75, 95% CI −7·92 to 0·42; p=0·08; IDEAS –0·95, −1·68 to −0·23; p=0·01). However, no diff erence was shown in the proportion of participants who had a reduction of more than 20% in overall symptoms (PANSS 85 [51%] in the intervention group vs 44 [51%] in the control group; p=0·89; IDEAS 75 [48%] vs 28 [35%]). We noted a signifi cant reduction in symptom and disability outcomes at the rural Tamil Nadu site (−9·29, −15·41 to −3·17; p=0·003). Two patients (one in each group) died by suicide during the study, and two patients died because of complications of a road traffi c accident and pre-existing cardiac disease. 18 (73%) patients (17 in the intervention group) were admitted to hospital during the course of the trial, of whom seven were admitted because of physical health problems, such as acute gastritis and vomiting, road accident, high fever, or cardiovascular disease.
Interpretation: The collaborative community-based care plus facility-based care intervention is modestly more eff ective than facility-based care, especially for reducing disability and symptoms of psychosis. Our results show that the study intervention is best implemented as an initial service in settings where services are scarce, for example in rural areas
Experiences of stigma and discrimination faced by family caregivers of people with schizophrenia in India.
Stigma associated with schizophrenia significantly affects family caregivers, yet few studies have examined the nature and determinants of family stigma and its relationship to their knowledge about the condition. This paper describes the experiences and determinants of stigma reported by the primary caregivers of people living with schizophrenia (PLS) in India. The study used mixed methods and was nested in a randomised controlled trial of community care for people with schizophrenia. Between November 2009 and October 2010, data on caregiver stigma and functional outcomes were collected from a sample of 282 PLS-caregiver dyads. In addition, 36 in-depth-interviews were conducted with caregivers. Quantitative findings indicate that 'high caregiver stigma' was reported by a significant minority of caregivers (21%) and that many felt uncomfortable to disclose their family member's condition (45%). Caregiver stigma was independently associated with higher levels of positive symptoms of schizophrenia, higher levels of disability, younger PLS age, household education at secondary school level and research site. Knowledge about schizophrenia was not associated with caregiver stigma. Qualitative data illustrate the various ways in which stigma affected the lives of family caregivers and reveal relevant links between caregiver-stigma related themes ('others finding out', 'negative reactions' and 'negative feelings and views about the self') and other themes in the data. Findings highlight the need for interventions that address both the needs of PLS and their family caregivers. Qualitative data also illustrate the complexities surrounding the relationship between knowledge and stigma and suggest that providing 'knowledge about schizophrenia' may influence the process of stigmatisation in both positive and negative ways. We posit that educational interventions need to consider context-specific factors when choosing anti-stigma-messages to be conveyed. Our findings suggest that messages such as 'recovery is possible' and 'no-one is to blame' may be more helpful than focusing on bio-medical knowledge alone
Experiences of stigma and discrimination of people with schizophrenia in India.
Stigma contributes greatly to the burden of schizophrenia and is a major obstacle to recovery, yet, little is known about the subjective experiences of those directly affected in low and middle income countries. This paper aims to describe the experiences of stigma and discrimination of people living with schizophrenia (PLS) in three sites in India and to identify factors influencing negative discrimination. The study used mixed methods and was nested in a randomised controlled trial of community care for schizophrenia. Between November 2009 and October 2010, data on four aspects of stigma experienced by PLS and several clinical variables were collected from 282 PLS and 282 caregivers and analysed using multivariate regression. In addition, in-depth-interviews with PLS and caregivers (36 each) were carried out and analysed using thematic analysis. Quantitative findings indicate that experiences of negative discrimination were reported less commonly (42%) than more internalised forms of stigma experience such as a sense of alienation (79%) and significantly less often than in studies carried out elsewhere. Experiences of negative discrimination were independently predicted by higher levels of positive symptoms of schizophrenia, lower levels of negative symptoms of schizophrenia, higher caregiver knowledge about symptomatology, lower PLS age and not having a source of drinking water in the home. Qualitative findings illustrate the major impact of stigma on 'what matters most' in the lives of PLS and highlight three key domains influencing the themes of 'negative reactions' and 'negative views and feelings about the self', i.e., 'others finding out', 'behaviours and manifestations of the illness' and 'reduced ability to meet role expectations'. Findings have implications for conceptualising and measuring stigma and add to the rationale for enhancing psycho-social interventions to support those facing discrimination. Findings also highlight the importance of addressing public stigma and achieving higher level social and political structural change
Collaborative community based care for people and their families living with schizophrenia in India: protocol for a randomised controlled trial
BACKGROUND: There is a large treatment gap with few community services for people with schizophrenia in low income countries largely due to the shortage of specialist mental healthcare human resources. Community based rehabilitation (CBR), involving lay health workers, has been shown to be feasible, acceptable and more effective than routine care for people with schizophrenia in observational studies. The aim of this study is to evaluate whether a lay health worker led, Collaborative Community Based Care (CCBC) intervention, combined with usual Facility Based Care (FBC), is superior to FBC alone in improving outcomes for people with schizophrenia and their caregivers in India. METHODS/DESIGN: This trial is a multi-site, parallel group randomised controlled trial design in India.The trial will be conducted concurrently at three sites in India where persons with schizophrenia will be screened for eligibility and recruited after providing informed consent. Trial participants will be randomly allocated in a 2:1 ratio to the CCBC+FBC and FBC arms respectively using an allocation sequence pre-prepared through the use of permuted blocks, stratified within site. The structured CCBC intervention will be delivered by trained lay community health workers (CHWs) working together with the treating Psychiatrist. We aim to recruit 282 persons with schizophrenia. The primary outcomes are reduction in severity of symptoms of schizophrenia and disability at 12 months. The study will be conducted according to good ethical practice, data analysis and reporting guidelines. DISCUSSION: If the additional CCBC intervention delivered by front line CHWs is demonstrated to be effective and cost-effective in comparison to usually available care, this intervention can be scaled up to expand coverage and improve outcomes for persons with schizophrenia and their caregivers in low income countries. TRIAL REGISTRATION: The trial is registered with the International Society for the Registration of Clinical Trials and the allocated unique ID number is ISRCTN 56877013
Dengue Virus Infection and Virus-Specific HLA-A2 Restricted Immune Responses in Humanized NOD-scid IL2rγnull Mice
BACKGROUND:The lack of a suitable animal model to study viral and immunological mechanisms of human dengue disease has been a deterrent to dengue research. METHODOLOGY/PRINCIPAL FINDINGS:We sought to establish an animal model for dengue virus (DENV) infection and immunity using non-obese diabetic/severe combined immunodeficiency interleukin-2 receptor gamma-chain knockout (NOD-scid IL2rgamma(null)) mice engrafted with human hematopoietic stem cells. Human CD45(+) cells in the bone marrow of engrafted mice were susceptible to in vitro infection using low passage clinical and established strains of DENV. Engrafted mice were infected with DENV type 2 by different routes and at multiple time points post infection, we detected DENV antigen and RNA in the sera, bone marrow, spleen and liver of infected engrafted mice. Anti-dengue IgM antibodies directed against the envelope protein of DENV peaked in the sera of mice at 1 week post infection. Human T cells that developed following engraftment of HLA-A2 transgenic NOD-scid IL2rgamma(null) mice with HLA-A2(+) human cord blood hematopoietic stem cells, were able to secrete IFN-gamma, IL-2 and TNF-alpha in response to stimulation with three previously identified A2 restricted dengue peptides NS4b 2353((111-119)), NS4b 2423((181-189)), and NS4a 2148((56-64)). CONCLUSIONS/SIGNIFICANCE:This is the first study to demonstrate infection of human cells and functional DENV-specific T cell responses in DENV-infected humanized mice. Overall, these mice should be a valuable tool to study the role of prior immunity on subsequent DENV infections
Mapping geographical inequalities in access to drinking water and sanitation facilities in low-income and middle-income countries, 2000-17
Background: Universal access to safe drinking water and sanitation facilities is an essential human right, recognised in the Sustainable Development Goals as crucial for preventing disease and improving human wellbeing. Comprehensive, high-resolution estimates are important to inform progress towards achieving this goal. We aimed to produce high-resolution geospatial estimates of access to drinking water and sanitation facilities. Methods: We used a Bayesian geostatistical model and data from 600 sources across more than 88 low-income and middle-income countries (LMICs) to estimate access to drinking water and sanitation facilities on continuous continent-wide surfaces from 2000 to 2017, and aggregated results to policy-relevant administrative units. We estimated mutually exclusive and collectively exhaustive subcategories of facilities for drinking water (piped water on or off premises, other improved facilities, unimproved, and surface water) and sanitation facilities (septic or sewer sanitation, other improved, unimproved, and open defecation) with use of ordinal regression. We also estimated the number of diarrhoeal deaths in children younger than 5 years attributed to unsafe facilities and estimated deaths that were averted by increased access to safe facilities in 2017, and analysed geographical inequality in access within LMICs. Findings: Across LMICs, access to both piped water and improved water overall increased between 2000 and 2017, with progress varying spatially. For piped water, the safest water facility type, access increased from 40·0% (95% uncertainty interval [UI] 39·4–40·7) to 50·3% (50·0–50·5), but was lowest in sub-Saharan Africa, where access to piped water was mostly concentrated in urban centres. Access to both sewer or septic sanitation and improved sanitation overall also increased across all LMICs during the study period. For sewer or septic sanitation, access was 46·3% (95% UI 46·1–46·5) in 2017, compared with 28·7% (28·5–29·0) in 2000. Although some units improved access to the safest drinking water or sanitation facilities since 2000, a large absolute number of people continued to not have access in several units with high access to such facilities (>80%) in 2017. More than 253 000 people did not have access to sewer or septic sanitation facilities in the city of Harare, Zimbabwe, despite 88·6% (95% UI 87·2–89·7) access overall. Many units were able to transition from the least safe facilities in 2000 to safe facilities by 2017; for units in which populations primarily practised open defecation in 2000, 686 (95% UI 664–711) of the 1830 (1797–1863) units transitioned to the use of improved sanitation. Geographical disparities in access to improved water across units decreased in 76·1% (95% UI 71·6–80·7) of countries from 2000 to 2017, and in 53·9% (50·6–59·6) of countries for access to improved sanitation, but remained evident subnationally in most countries in 2017. Interpretation: Our estimates, combined with geospatial trends in diarrhoeal burden, identify where efforts to increase access to safe drinking water and sanitation facilities are most needed. By highlighting areas with successful approaches or in need of targeted interventions, our estimates can enable precision public health to effectively progress towards universal access to safe water and sanitation
The genetic architecture of the human cerebral cortex
The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder