ABSTRACT
The Caatinga, an exclusive biome in Brazil, is the largest tropical dry forest area in the Americas. It is characterized by a semi-arid climate and various soils that harbor a great diversity of flora and fauna. Novel records of aerial insectivorous bat species in the family Molossidae in the Chapada Diamantina, northeastern Brazil are presented. The study is based on field sampling of 115 molossid bat specimens from six genera and 12 taxonomically confirmed species, along with four taxa requiring further evaluation for definitive species identification. All specimens were obtained using mist nets around a small freshwater lagoon surrounded by semideciduous dry forest. The verified genera were Cynomops, Eumops, Molossops, Molossus, Neoplatymops, and Nyctinomops. Our findings enhance the understanding of bat diversity in the Brazilian Caatinga, with the first records of Eumopsdelticus, E.bonariensis, and Molossuscurrentium. The most abundant species were Molossusrufus, Eumopsglaucinus, Cynomopsplanirostris, Nyctinomopslaticaudatus, and Molossusmolossus. Previously unreported morphological and morphometric variations for these Caatinga taxa were examined. Additionally, information on sexual dimorphism in craniodental characteristics of Molossopstemminckii and variations in the presence of the sagittal crest in Neoplatymopsmattogrossensis are provided. Based on the voucher specimens from this study, the recognized number of species of Molossidae known from the Caatinga has increased to 21. Our results offer new insights into the taxonomy and biogeography of Neotropical molossids, highlighting their importance as members of bat communities in dry forest ecosystems from northeastern South America.
ABSTRACT
Amazonia contains the most extensive tropical forests on Earth, but Amazon carbon sinks of atmospheric CO2 are declining, as deforestation and climate-change-associated droughts1-4 threaten to push these forests past a tipping point towards collapse5-8. Forests exhibit complex drought responses, indicating both resilience (photosynthetic greening) and vulnerability (browning and tree mortality), that are difficult to explain by climate variation alone9-17. Here we combine remotely sensed photosynthetic indices with ground-measured tree demography to identify mechanisms underlying drought resilience/vulnerability in different intact forest ecotopes18,19 (defined by water-table depth, soil fertility and texture, and vegetation characteristics). In higher-fertility southern Amazonia, drought response was structured by water-table depth, with resilient greening in shallow-water-table forests (where greater water availability heightened response to excess sunlight), contrasting with vulnerability (browning and excess tree mortality) over deeper water tables. Notably, the resilience of shallow-water-table forest weakened as drought lengthened. By contrast, lower-fertility northern Amazonia, with slower-growing but hardier trees (or, alternatively, tall forests, with deep-rooted water access), supported more-drought-resilient forests independent of water-table depth. This functional biogeography of drought response provides a framework for conservation decisions and improved predictions of heterogeneous forest responses to future climate changes, warning that Amazonia's most productive forests are also at greatest risk, and that longer/more frequent droughts are undermining multiple ecohydrological strategies and capacities for Amazon forest resilience.
Subject(s)
Drought Resistance , Droughts , Forests , Groundwater , Photosynthesis , Soil , Sunlight , Trees , Brazil , Carbon Sequestration , Droughts/statistics & numerical data , Groundwater/analysis , Soil/chemistry , Trees/classification , Trees/metabolism , Trees/physiology , Tropical Climate , Drought Resistance/physiology , Phylogeography , Conservation of Natural ResourcesABSTRACT
During the course of a study of Condalia buxifolia (Rhamnaceae), one new cyclopeptide alkaloid condaline B (1), together with six known cyclopeptide alkaloids, condaline A (2), and the scutianines B (3), - D (4) and -E (5), frangulanine (6), and 3,4,28-tris-epi-scutianene N (7), were isolated from the rind bark of Condalia buxifolia. Their structures have been confirmed through spectroscopic analyses such as 1D and 2D NMR experiments. The absolute stereochemistry of condaline A (2), was elucidated by X-ray crystal structure determination of its HI salt. In addition, condaline B (1) was obtained synthetically through a structural transformation of condaline A. Meanwhile, the crude methanol extract, the basic ether fraction, and alkaloids 1-7 were tested against various strains of Gram-positive and Gram-negative bacteria and fungus, showing promising antimicrobial activity.
Subject(s)
Alkaloids , Rhamnaceae , Alkaloids/chemistry , Anti-Bacterial Agents , Gram-Negative Bacteria , Gram-Positive Bacteria , Molecular Structure , Peptides, Cyclic/pharmacology , Plant Bark/chemistry , Rhamnaceae/chemistryABSTRACT
OBJECTIVE: This study aims to analyze the psychometric properties of the new Brazilian-Portuguese version of the Brief Resilience Scale (B-BRS) in older adults. METHOD: A sample of 1251 participants (54.20% women; M = 68.02 years, SD = 6.52) completed the B-BRS and seven scales on successful aging and mental health. Confirmatory factor analysis was used to study the B-BRS dimensionality. Convergent and divergent validity was analyzed by means of examining the relationships of B-BRS with scales on successful aging and mental health. RESULTS: The results supported the unidimensionality of the B-BRS after controlling for wording method, as well as satisfactory reliability (ω = .79). B-BRS structure remained invariant across education level and income groups. B-BRS scores positively correlated with successful aging factors and negatively with psychopathology symptoms. CONCLUSION: To conclude, our findings provide some evidence on the reliability and validity of the B-BRS, as well as its validation for use in the senior population.
Subject(s)
Benchmarking , Resilience, Psychological , Aged , Brazil , Female , Humans , Male , Portugal , Psychometrics , Reproducibility of Results , Surveys and QuestionnairesABSTRACT
We use an ultrasonic standing wave to simultaneously trap and deform thousands of soft lipid vesicles immersed in a liquid solution. In our device, acoustic radiation stresses comparable in magnitude to those generated in optical stretching devices are achieved over a spatial extent of more than ten acoustic wavelengths. We solve the acoustic scattering problem in the long-wavelength limit to obtain the radiation stress. The result is then combined with thin-shell elasticity theory to form expressions that relate the deformed geometry to the applied acoustic field intensity. Using observation of the deformed geometry and this model, we rapidly extract mechanical properties, such as the membrane Young's modulus, from populations of lipid vesicles.
ABSTRACT
The analytical solution of the acoustic radiation force exerted by a beam of arbitrary shape on a small spheroidal rigid particle suspended in an ideal fluid is presented. The particle is assumed to be much smaller than the wavelength, i.e., the so-called long-wavelength approximation. Based on this theoretical development, closed-form expressions for the radiation force of a traveling and standing plane wave exerted on a prolate spheroidal particle are derived in the dipole approximation. As validation, the previous analytical result considering a standing wave interacting with a spheroid in axisymmetric configuration is recovered, as well as numerical results obtained with the boundary-element method.
ABSTRACT
The value of sharing scientific research data is widely appreciated, but factors that hinder or prompt the reuse of data remain poorly understood. Using the Theory of Reasoned Action, we test the relationship between the beliefs and attitudes of scientists towards data reuse, and their self-reported data reuse behaviour. To do so, we used existing responses to selected questions from a worldwide survey of scientists developed and administered by the DataONE Usability and Assessment Working Group (thus practicing data reuse ourselves). Results show that the perceived efficacy and efficiency of data reuse are strong predictors of reuse behaviour, and that the perceived importance of data reuse corresponds to greater reuse. Expressed lack of trust in existing data and perceived norms against data reuse were not found to be major impediments for reuse contrary to our expectations. We found that reported use of models and remotely-sensed data was associated with greater reuse. The results suggest that data reuse would be encouraged and normalized by demonstration of its value. We offer some theoretical and practical suggestions that could help to legitimize investment and policies in favor of data sharing.
Subject(s)
Attitude , Information Dissemination , Science , Humans , Models, Psychological , WorkforceABSTRACT
OBJECTIVE: To examine the association between maternal body mass index (BMI) and serum 25-hydroxy vitamin D [25(OH)D] concentration and bone density in mother-infant pairs. STUDY DESIGN: The study was a secondary analysis of 234 exclusively breastfeeding dyads who were recruited in the first postpartum month for a randomized controlled trial of maternal vs infant vitamin D supplementation. Mean 25(OH)D concentrations and bone mineral density (BMD) were compared by BMI group. The adjusted association between maternal BMI and 25(OH)D and bone density was examined at 1, 4, and 7 months postpartum. RESULTS: Obese breastfeeding women had lower 25(OH)D concentrations and higher BMD than lean women at all 3 time points (P < .01). Higher maternal BMI was associated with lower maternal serum levels of 25(OH)D at 1, 4, and 7 months postpartum (adjusted ß = -0.45 ng/ml per kg/m2, 95% CI -.076, -0.14, at 1 month) and higher BMD at the same time points (ß = 0.006 BMD z score; 95% CI 0.003, 0.01 at 1 month). Seventy-six percent of infants were vitamin D deficient at 1 month of age. Infants born to overweight and obese mothers had lower 25(OH)D concentrations than infants of lean mothers (P < .01). For infants in the maternal supplementation group, higher maternal BMI was associated with lower 25(OH)D concentrations at 4 months (ß = -0.68; 95% CI -1.17, -0.20) and lower bone density at 7 months (ß = -0.001; 95% CI -0.002, -0.0001). CONCLUSIONS: In exclusively breastfeeding dyads, maternal obesity is associated with lower maternal and infant serum 25(OH)D concentrations, which may impact infant bone density. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00412074.
Subject(s)
Bone Density , Breast Feeding , Obesity/physiopathology , Vitamin D/analogs & derivatives , Adult , Body Mass Index , Dietary Supplements , Double-Blind Method , Female , Humans , Infant , Infant, Newborn , Maternal Nutritional Physiological Phenomena , Mothers , Vitamin D/bloodABSTRACT
Researchers have utilized chemical fingerprints in the determination of habitat utilization and movements of the aquatic animals. In the present effort, we analyzed polychlorinated biphenyl (PCB) congeners and organochlorine pesticides in the samples of juvenile bluefin tuna caught offshore of Virginia, and in larger bluefin tuna from the Gulf of Maine and near Nova Scotia. For a given specimen, or a given location, PCB concentrations were highest, followed by DDTs, and chlordanes. Average contaminant concentrations from fish captured from the three locations were not significantly different; and PCBs, DDTs, and chlordanes correlated well with each other. Trans-nonachlor/PCB 153 ratios in bluefin tuna of eastern Atlantic (i.e., Mediterranean) origin are low compared to the corresponding ratios in fish in the western Atlantic. As the former migrate to the western Atlantic, these ratios gradually turnover due to the accumulation of biomass from forage contaminated with higher trans-nonachlor/PCB 153 ratio reflecting dissimilar use of chlordane pesticides on two sides of the Atlantic Ocean. The trans-nonachlor/PCB 153 ratio indicated that one juvenile bluefin tuna from offshore of Virginia and one large bluefin tuna from Gulf of Maine in the present study originated from foraging grounds in the Mediterranean Sea, and that they have made the trans-Atlantic migrations. The remaining individuals were determined to be either spawned in the Gulf of Mexico or the trans-nonachlor/PCB 153 ratio for the putative Mediterranean bluefin tuna was completely turned over to resemble the ratio characteristic to the western Atlantic. Based on the turnover time for trans-nonachlor/PCB 153 ratio previously determined, the residence time of juvenile bluefin tuna offshore Virginia was estimated to be at least 0.8 to 1.6years. A discriminant function analysis (DFA) plot of total PCB normalized signatures of PCB congeners showed three separate clusters, which suggested that bluefin tuna from offshore Virginia, Gulf of Maine, and Nova Scotia could have had extended residences and foraging within the areas of capture to be able to sustain the stable signatures of PCB congeners. The DFA cluster results supported the concept of metapopulation theory of spatial ecology comprising discrete aggregates of local populations of bluefin tuna where the desired prey species are likely to be abundant. Despite their highly migratory trait and endothermic advantage of foraging in broader and colder habitats, the movements and mixing across the aggregation ranges related to feeding did not appear to be extensive. Advancement in the understanding of bluefin tuna population dynamics beyond the coarse concept of trans-Atlantic migrations to the metapopulation hypothesis provides a novel exploratory tool in the stock assessment and resource management. As the chemical tracer tags are fortified naturally and document the time- and space-integrated foraging history, they promise to serve as the low-cost alternatives to the high-cost electronic data recording tags employed for addressing the migratory movements of bluefin tuna. Between the different potential chemical tracer tags, a distinct advantage of PCB/pesticide analysis over the otolith micro-constituent analysis is that the muscle tissue of a given individual bluefin tuna can be sampled repeatedly for PCB/pesticide analysis over different spatial and temporal scales in a non-lethal manner.
Subject(s)
Environmental Monitoring/methods , Hydrocarbons, Chlorinated/metabolism , Pesticides/metabolism , Polychlorinated Biphenyls/metabolism , Tuna/metabolism , Water Pollutants, Chemical/metabolism , Animals , Atlantic Ocean , Biomass , Ecosystem , Hydrocarbons, Chlorinated/analysis , Maine , Mediterranean Sea , Mexico , Nova Scotia , Otolithic Membrane , Pesticides/analysis , Polychlorinated Biphenyls/analysis , Population Dynamics , Virginia , Water Pollutants, Chemical/analysisABSTRACT
OBJECTIVE: To determine whether upper gastrointestinal tract (UGI) bypass itself has beneficial effects on the factors involved in regulating glucose homeostasis in patients with type 2 diabetes (T2D). METHODS: A 12-month randomized controlled trial was conducted in 17 overweight/obese subjects with T2D, who received standard medical care (SC, n = 7, BMI = 31.7 ± 3.5 kg/m(2) ) or duodenal-jejunal bypass surgery with minimal gastric resection (DJBm) (n = 10; BMI = 29.7 ± 1.9 kg/m(2)). A 5-h modified oral glucose tolerance test was performed at baseline and at 1, 6, and 12 months after surgery or starting SC. RESULTS: Body weight decreased progressively after DJBm (7.9 ± 4.1%, 9.6 ± 4.2%, and 10.2 ± 4.3% at 1, 6, and 12 months, respectively) but remained stable in the SC group (P < 0.001). DJBm, but not SC, improved: (1) oral glucose tolerance (decreased 2-h glucose concentration, P = 0.039), (2) insulin sensitivity (decreased homeostasis model assessment of insulin resistance, P = 0.013), (3) early insulin response to a glucose load (increased insulinogenic index, P = 0.022), and (4) overall glycemic control (reduction in HbA1c with fewer diabetes medications). CONCLUSIONS: DJBm causes moderate weight loss and improves metabolic function in T2D. However, our study cannot separate the benefits of moderate weight loss from the potential therapeutic effect of UGI tract bypass itself on the observed metabolic improvements.
Subject(s)
Diabetes Mellitus, Type 2/surgery , Duodenum/surgery , Jejunum/surgery , Obesity/surgery , Adult , Aged , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/metabolism , Female , Gastric Bypass/methods , Glucose Tolerance Test , Humans , Insulin Resistance/physiology , Male , Middle Aged , Obesity/metabolism , Weight Loss/physiologyABSTRACT
OBJECTIVES: The study objectives were to (1) compare the safety of high-risk surgical aortic valve replacement in the Placement of Aortic Transcatheter Valves (PARTNER) I trial with Society of Thoracic Surgeons national benchmarks; (2) reference intermediate-term survival to that of the US population; and (3) identify subsets of patients for whom aortic valve replacement may be futile, with no survival benefit compared with therapy without aortic valve replacement. METHODS: From May 2007 to October 2009, 699 patients with high surgical risk, aged 84 ± 6.3 years, were randomized in PARTNER-IA; 313 patients underwent surgical aortic valve replacement. Median follow-up was 2.8 years. Survival for therapy without aortic valve replacement used 181 PARTNER-IB patients. RESULTS: Operative mortality was 10.5% (expected 9.3%), stroke 2.6% (expected 3.5%), renal failure 5.8% (expected 12%), sternal wound infection 0.64% (expected 0.33%), and prolonged length of stay 26% (expected 18%). However, calibration of observed events in this relatively small sample was poor. Survival at 1, 2, 3, and 4 years was 75%, 68%, 57%, and 44%, respectively, lower than 90%, 81%, 73%, and 65%, respectively, in the US population, but higher than 53%, 32%, 21%, and 14%, respectively, in patients without aortic valve replacement. Risk factors for death included smaller body mass index, lower albumin, history of cancer, and prosthesis-patient mismatch. Within this high-risk aortic valve replacement group, only the 8% of patients with the poorest risk profiles had estimated 1-year survival less than that of similar patients treated without aortic valve replacement. CONCLUSIONS: PARTNER selection criteria for surgical aortic valve replacement, with a few caveats, may be more appropriate, realistic indications for surgery than those of the past, reflecting contemporary surgical management of severe aortic stenosis in high-risk patients at experienced sites.
Subject(s)
Aortic Valve Stenosis/surgery , Aortic Valve/surgery , Health Care Rationing , Heart Valve Prosthesis Implantation , Patient Selection , Process Assessment, Health Care , Aged , Aged, 80 and over , Aortic Valve Stenosis/diagnosis , Aortic Valve Stenosis/mortality , Benchmarking , Female , Health Care Rationing/standards , Heart Valve Prosthesis Implantation/adverse effects , Heart Valve Prosthesis Implantation/mortality , Heart Valve Prosthesis Implantation/standards , Hospital Mortality , Humans , Kaplan-Meier Estimate , Male , Medical Futility , Postoperative Complications/mortality , Process Assessment, Health Care/standards , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome , United StatesABSTRACT
We map the extent, infer the life-cycle length and describe spatial and temporal patterns of flowering of sarmentose bamboos (Guadua spp) in upland forests of the southwest Amazon. We first examine the spectra and the spectral separation of forests with different bamboo life stages. False-color composites from orbital sensors going back to 1975 are capable of distinguishing life stages. These woody bamboos flower produce massive quantities of seeds and then die. Life stage is synchronized, forming a single cohort within each population. Bamboo dominates at least 161,500 km(2) of forest, coincident with an area of recent or ongoing tectonic uplift, rapid mechanical erosion and poorly drained soils rich in exchangeable cations. Each bamboo population is confined to a single spatially continuous patch or to a core patch with small outliers. Using spatial congruence between pairs of mature-stage maps from different years, we estimate an average life cycle of 27-28 y. It is now possible to predict exactly where and approximately when new bamboo mortality events will occur. We also map 74 bamboo populations that flowered between 2001 and 2008 over the entire domain of bamboo-dominated forest. Population size averaged 330 km(2). Flowering events of these populations are temporally and/or spatially separated, restricting or preventing gene exchange. Nonetheless, adjacent populations flower closer in time than expected by chance, forming flowering waves. This may be a consequence of allochronic divergence from fewer ancestral populations and suggests a long history of widespread bamboo in the southwest Amazon.
Subject(s)
Bambusa , Flowers , Trees , Cluster Analysis , Geography , South AmericaABSTRACT
OBJECTIVES: To determine the incidence of vitamin D deficiency in neonates with congenital heart disease and whether differences exist by race. In addition, we determined the effect of cardiopulmonary bypass on vitamin D levels and explored associations between 25-hydroxyvitamin D [25(OH)D] levels and postoperative outcomes. STUDY DESIGN: We performed a secondary analysis of a prospective randomized controlled trial in 70 neonates undergoing cardiac surgery. The neonates' 25(OH)D levels were measured in the operating room before skin incision (baseline), at the cessation of cardiopulmonary bypass, and at 24 hours postoperatively. Associations between these levels and clinical outcomes were explored. Vitamin D deficiency was defined as a 25(OH)D level <20 ng/mL. RESULTS: Vitamin D deficiency was present in 84% (59/70); concentrations in African Americans (n = 20) were significantly lower than those of Caucasian/other race/ethnicity (n = 50) (10.2 ± 4.2 vs 16.0 ± 5.6 ng/mL, P < .0001). The 24-hour postoperative 25(OH)D levels were not different from baseline and correlated with a reduced postoperative inotropic requirement (r = -0.316, P = .008). CONCLUSIONS: Vitamin D deficiency is prevalent in neonates with congenital cardiac defects, and lower postoperative 25(OH)D levels are associated with the need for increased inotropic support in neonates undergoing cardiac operations. These findings support that vitamin D deficiency may play a role in myocardial injury and postoperative recovery and warrants further investigation.
Subject(s)
Vitamin D/blood , Cardiac Surgical Procedures , Cardiopulmonary Bypass , Ethnicity , Female , Heart Defects, Congenital/ethnology , Heart Defects, Congenital/surgery , Humans , Infant, Newborn , Male , Myocardium/pathology , Prevalence , Prospective Studies , Randomized Controlled Trials as Topic , Research Design , Treatment Outcome , Vitamin D/analogs & derivatives , Vitamin D/metabolism , Vitamin D DeficiencyABSTRACT
OBJECTIVE: To determine the association among nonalcoholic fatty liver disease (NAFLD), metabolic function, and cardiac function in obese adolescents. STUDY DESIGN: Intrahepatic triglyceride (IHTG) content (magnetic resonance spectroscopy), insulin sensitivity and ß-cell function (5-hour oral glucose tolerance test with mathematical modeling), and left ventricular function (speckle tracking echocardiography) were determined in 3 groups of age, sex, and Tanner matched adolescents: (1) lean (n=14, body mass index [BMI]=20±2 kg/m2); (2) obese with normal (2.5%) IHTG content (n=15, BMI=35±3 kg/m2); and (3) obese with increased (8.7%) IHTG content (n=15, BMI=37±6 kg/m2). RESULTS: The disposition index (ß-cell function) and insulin sensitivity index were â¼45% and â¼70% lower, respectively, and whole body insulin resistance, calculated by homeostasis model of assessment-insulin resistance (HOMA-IR), was â¼60% greater, in obese than in lean subjects, and â¼30% and â¼50% lower and â¼150% greater, respectively, in obese subjects with NAFLD than those without NAFLD (P<.05 for all). Left ventricular global longitudinal systolic strain and early diastolic strain rates were significantly decreased in obese than in lean subjects, and in obese subjects with NAFLD than those without NAFLD (P<.05 for all), and were independently associated with HOMA-IR (ß=0.634). IHTG content was the only significant independent determinant of insulin sensitivity index (ß=-0.770), disposition index (ß=-0.651), and HOMA-IR (ß=0.738). CONCLUSIONS: These findings demonstrate that the presence of NAFLD in otherwise asymptomatic obese adolescents is an early marker of cardiac dysfunction.
Subject(s)
Fatty Liver/physiopathology , Heart Ventricles/pathology , Heart Ventricles/physiopathology , Liver/physiopathology , Obesity/complications , Adolescent , Body Mass Index , Cross-Sectional Studies , Fatty Liver/metabolism , Female , Humans , Insulin Resistance , Liver/metabolism , Magnetic Resonance Spectroscopy , Male , Non-alcoholic Fatty Liver Disease , Obesity/metabolism , Obesity/physiopathology , Triglycerides/metabolismABSTRACT
BACKGROUND: The dengue virus serotype 3 (DENV-3) Indian subcontinent strain emerged in Puerto Rico in 1998 after a 21-year absence. The rapid expansion of DENV-3 on the island correlated with the withdrawal of the other serotypes for 7 years. The DENV-3 prevalence declined in 2008 and remains undetected. METHODS: We sequenced complete genomes of 92 DENV-3 clinical isolates to characterize the molecular evolution and phylogeography throughout 10 years of continued sampling (19982007). RESULTS: We documented 8 distinct lineages that emerged simultaneously and evolved independently. Two of the 8 lineages were highly associated with transient introductions of foreign viruses, and 2 of the 3 endemic lineages covered the entire study period. We found evidence of temporal-geographical clustering only within the 3 endemic lineages. The phylogeography analysis combined with serotype-specific incidence data showed that transmission of a DENV serotype in a given location and time is usually correlated with the absence of the other serotype. CONCLUSIONS: Our study shows the cotransmission of DENV-3 lineages through a complex dissemination pattern dissimilar to the evolutionary dynamics of the other serotypes in the island. High virus genetic diversity and a large naive population were underlying factors in the expansion and collapse of DENV-3 in Puerto Rico.
Subject(s)
Dengue Virus/classification , Dengue/virology , Genetic Variation , Base Sequence , DNA, Viral , Dengue/epidemiology , Epidemics , Genome, Viral , Humans , Phylogeny , Population Surveillance , Puerto Rico/epidemiology , Serotyping , Time FactorsABSTRACT
INTRODUCTION: Familial hypobetalipoproteinemia (FHBL) is an autosomal dominant disease characterized by abnormally low levels of apolipoprotein-B (apoB) containing lipoproteins. FHBL is caused by APOB, PCSK9 or ANGPTL3 mutations or is associated with loci located in chromosomes 10 and 3p21. However, other genes should be involved. This study describes the kinetic parameters of the apoB containing lipoproteins and sequence abnormalities of the APOB and PCSK9 genes of FHBL patients identified in a large hospital based survey. MATERIAL AND METHODS: Cases with primary or secondary causes of hypobetalipoproteinemia were identified. ApoB kinetics were measured in cases with primary forms in whom truncated forms of apoB were not present in VLDL (n = 4). A primed constant infusion of [(13)C] leucine was administered, VLDL and LDL apoB production and catabolic rates measured by a multicompartmental model and compared to normolipemic controls. In addition, these subjects had an abdominal ultrasound and direct sequencing was carried out for the PCSK9 and apoB genes. RESULTS: Three individuals had normal apoB production with increased catabolic rate; the remaining had reduced synthetic and catabolic rates. Various polymorphisms, some of them previously unreported (*), in the PCSK9 gene (R46L, A53V, I474V, D480N*, E498K*) and in the apoB gene (N441D*, Y1395C, P2712L, D2285E*, I2286V, T3540S*, T3799M*) were found in the FHBL patients. We found hepatic ultrasound changes of hepatic steatosis in only one of the four probands. CONCLUSION: FHBL without truncated apoB is a heterogeneous disease from a metabolic and a genetic perspective. Hypobetalipoproteinemia is a risk factor but not an obligate cause of steatosis.
Subject(s)
Apolipoprotein B-100/genetics , Fatty Liver , Hypobetalipoproteinemias , Serine Endopeptidases/genetics , Adult , Carbon Isotopes , Data Collection , Fatty Liver/epidemiology , Fatty Liver/genetics , Fatty Liver/metabolism , Female , Genotype , Hospitals/statistics & numerical data , Humans , Hypobetalipoproteinemias/epidemiology , Hypobetalipoproteinemias/genetics , Hypobetalipoproteinemias/metabolism , Inpatients/statistics & numerical data , Leucine/pharmacokinetics , Liver/diagnostic imaging , Liver Function Tests , Male , Middle Aged , Models, Genetic , Non-alcoholic Fatty Liver Disease , Pedigree , Polymorphism, Genetic , Proprotein Convertase 9 , Proprotein Convertases , UltrasonographyABSTRACT
PURPOSE: Previous studies have suggested that higher plasma 25-hydroxyvitamin D(3) [25(OH)D] levels are associated with decreased colorectal cancer risk and improved survival, but the prevalence of vitamin D deficiency in advanced colorectal cancer and its influence on outcomes are unknown. PATIENTS AND METHODS: We prospectively measured plasma 25(OH)D levels in 515 patients with stage IV colorectal cancer participating in a randomized trial of chemotherapy. Vitamin D deficiency was defined as 25(OH)D lower than 20 ng/mL, insufficiency as 20 to 29 ng/mL, and sufficiency as ≥ 30 ng/mL. We examined the association between baseline 25(OH)D level and selected patient characteristics. Cox proportional hazards models were used to calculate hazard ratios (HR) for death, disease progression, and tumor response, adjusted for prognostic factors. RESULTS: Among 515 eligible patients, 50% of the study population was vitamin D deficient, and 82% were vitamin D insufficient. Plasma 25(OH)D levels were lower in black patients compared to white patients and patients of other race (median, 10.7 v 21.1 v 19.3 ng/mL, respectively; P < .001), and females compared to males (median, 18.3 v 21.7 ng/mL, respectively; P = .0005). Baseline plasma 25(OH)D levels were not associated with patient outcome, although given the distribution of plasma levels in this cohort, statistical power for survival analyses were limited. CONCLUSION: Vitamin D deficiency is highly prevalent among patients with stage IV colorectal cancer receiving first-line chemotherapy, particularly in black and female patients.
Subject(s)
Adenocarcinoma/blood , Colorectal Neoplasms/blood , Vitamin D Deficiency/blood , Vitamin D/analogs & derivatives , Adenocarcinoma/drug therapy , Adenocarcinoma/mortality , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers/blood , Canada , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Disease Progression , Female , Humans , Logistic Models , Male , Middle Aged , Neoplasm Staging , Prevalence , Proportional Hazards Models , Prospective Studies , Puerto Rico , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome , United States , Vitamin D/blood , Vitamin D Deficiency/mortalityABSTRACT
To study the evolution of dengue virus (DENV) serotype 2 in Puerto Rico, we examined the genetic composition and diversity of 160 DENV-2 genomes obtained through 22 consecutive years of sampling. A clade replacement took place in 1994-1997 during a period of high incidence of autochthonous DENV-2 and frequent, short-lived reintroductions of foreign DENV-2. This unique clade replacement was complete just before DENV-3 emerged. By temporally and geographically defining DENV-2 lineages, we describe a refuge of this virus through 4 years of low genome diversity. Our analyses may explain the long-term endurance of DENV-2 despite great epidemiologic changes in disease incidence and serotype distribution.
Subject(s)
Dengue Virus/classification , Dengue Virus/genetics , Dengue/epidemiology , Disease Outbreaks , Dengue/virology , Evolution, Molecular , Genetic Variation , Humans , Incidence , Phylogeny , Puerto Rico/epidemiologyABSTRACT
RATIONALE: Maternal vitamin D intake during pregnancy has been inversely associated with asthma symptoms in early childhood. However, no study has examined the relationship between measured vitamin D levels and markers of asthma severity in childhood. OBJECTIVES: To determine the relationship between measured vitamin D levels and both markers of asthma severity and allergy in childhood. METHODS: We examined the relation between 25-hydroxyvitamin D levels (the major circulating form of vitamin D) and markers of allergy and asthma severity in a cross-sectional study of 616 Costa Rican children between the ages of 6 and 14 years. Linear, logistic, and negative binomial regressions were used for the univariate and multivariate analyses. MEASUREMENTS AND MAIN RESULTS: Of the 616 children with asthma, 175 (28%) had insufficient levels of vitamin D (<30 ng/ml). In multivariate linear regression models, vitamin D levels were significantly and inversely associated with total IgE and eosinophil count. In multivariate logistic regression models, a log(10) unit increase in vitamin D levels was associated with reduced odds of any hospitalization in the previous year (odds ratio [OR], 0.05; 95% confidence interval [CI], 0.004-0.71; P = 0.03), any use of antiinflammatory medications in the previous year (OR, 0.18; 95% CI, 0.05-0.67; P = 0.01), and increased airway responsiveness (a < or =8.58-mumol provocative dose of methacholine producing a 20% fall in baseline FEV(1) [OR, 0.15; 95% CI, 0.024-0.97; P = 0.05]). CONCLUSIONS: Our results suggest that vitamin D insufficiency is relatively frequent in an equatorial population of children with asthma. In these children, lower vitamin D levels are associated with increased markers of allergy and asthma severity.
Subject(s)
Asthma/blood , Severity of Illness Index , Vitamin D/analogs & derivatives , Adolescent , Anti-Inflammatory Agents/therapeutic use , Biomarkers/blood , Bronchial Provocation Tests , Bronchoconstrictor Agents , Child , Costa Rica , Eosinophils/metabolism , Female , Forced Expiratory Volume , Hospitalization/statistics & numerical data , Humans , Hypersensitivity/blood , Immunoglobulin E/blood , Leukocyte Count , Male , Methacholine Chloride , Multivariate Analysis , Spirometry , Vitamin D/bloodABSTRACT
The high incidence of coral disease in shallow coastal marine environments suggests seawater depth and coastal pollution have an impact on the microbial communities inhabiting healthy coral tissues. A study was undertaken to determine how bacterial communities inhabiting tissues of the coral Montastraea annularis change at 5 m, 10 m and 20 m water depth in varying proximity to the urban centre and seaport of Willemstad, Curaçao, Netherlands Antilles. Analyses of terminal restriction fragment length polymorphisms (TRFLP) of 16S rRNA gene sequences show significant differences in bacterial communities of polluted and control localities only at the shallowest seawater depth. Furthermore, distinct differences in bacterial communities were found with increasing water depth. Comparisons of TRFLP peaks with sequenced clone libraries indicate the black band disease cyanobacterium clone CD1C11 is common and most abundant on healthy corals in less than 10 m water depth. Similarly, sequences belonging to a previously unrecognized group of likely phototrophic bacteria, herein referred to as CAB-I, were also more common in shallow water. To assess the influence of environmental and physiologic factors on bacterial community structure, canonical correspondence analysis was performed using explanatory variables associated with: (i) light availability; (ii) seawater pollution; (iii) coral mucus composition; (iv) the community structure of symbiotic algae; and (v) the photosynthetic activity of symbiotic algae. Eleven per cent of the variation in bacterial communities was accounted for by covariation with these variables; the most important being photosynthetically active radiation (sunlight) and the coral uptake of sewage-derived compounds as recorded by the delta(15)N of coral tissue.