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1.
N Engl J Med ; 385(21): 1951-1960, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34407339

RESUMEN

BACKGROUND: Early administration of convalescent plasma obtained from blood donors who have recovered from coronavirus disease 2019 (Covid-19) may prevent disease progression in acutely ill, high-risk patients with Covid-19. METHODS: In this randomized, multicenter, single-blind trial, we assigned patients who were being treated in an emergency department for Covid-19 symptoms to receive either one unit of convalescent plasma with a high titer of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or placebo. All the patients were either 50 years of age or older or had one or more risk factors for disease progression. In addition, all the patients presented to the emergency department within 7 days after symptom onset and were in stable condition for outpatient management. The primary outcome was disease progression within 15 days after randomization, which was a composite of hospital admission for any reason, seeking emergency or urgent care, or death without hospitalization. Secondary outcomes included the worst severity of illness on an 8-category ordinal scale, hospital-free days within 30 days after randomization, and death from any cause. RESULTS: A total of 511 patients were enrolled in the trial (257 in the convalescent-plasma group and 254 in the placebo group). The median age of the patients was 54 years; the median symptom duration was 4 days. In the donor plasma samples, the median titer of SARS-CoV-2 neutralizing antibodies was 1:641. Disease progression occurred in 77 patients (30.0%) in the convalescent-plasma group and in 81 patients (31.9%) in the placebo group (risk difference, 1.9 percentage points; 95% credible interval, -6.0 to 9.8; posterior probability of superiority of convalescent plasma, 0.68). Five patients in the plasma group and 1 patient in the placebo group died. Outcomes regarding worst illness severity and hospital-free days were similar in the two groups. CONCLUSIONS: The administration of Covid-19 convalescent plasma to high-risk outpatients within 1 week after the onset of symptoms of Covid-19 did not prevent disease progression. (SIREN-C3PO ClinicalTrials.gov number, NCT04355767.).


Asunto(s)
COVID-19/terapia , Progresión de la Enfermedad , SARS-CoV-2/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , COVID-19/complicaciones , COVID-19/inmunología , COVID-19/mortalidad , Servicio de Urgencia en Hospital , Femenino , Hospitalización , Humanos , Inmunización Pasiva , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Factores de Riesgo , Método Simple Ciego , Insuficiencia del Tratamiento , Adulto Joven , Sueroterapia para COVID-19
2.
Phys Rev Lett ; 132(6): 062702, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38394565

RESUMEN

The cross section of the ^{13}C(α,n)^{16}O reaction is needed for nuclear astrophysics and applications to a precision of 10% or better, yet inconsistencies among 50 years of experimental studies currently lead to an uncertainty of ≈15%. Using a state-of-the-art neutron detection array, we have performed a high resolution differential cross section study covering a broad energy range. These measurements result in a dramatic improvement in the extrapolation of the cross section to stellar energies potentially reducing the uncertainty to ≈5% and resolving long standing discrepancies in higher energy data.

3.
Public Health ; 227: 49-53, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38104419

RESUMEN

OBJECTIVES: The World Health Organization has declared that COVID-19 is no longer a public health emergency of international concern. Nevertheless, it remains a public health issue, and seasonal vaccinations, at the same time of year as influenza vaccinations, will be necessary. When the first vaccines were administered in 2020, decision-makers had to make assumptions about the best methods to communicate and administer vaccines to increase uptake. Now, a body of evidence can inform these decisions. STUDY DESIGN: A narrative review written by three behavioural scientists who design research for policy. METHODS: We searched the PubMed database for: (i) reviews of interventions to increase uptake of COVID-19 or influenza vaccines and (ii) empirical studies on uptake of COVID-19 and influenza vaccines. In addition, registered trials gathered by a Cochrane scoping review of interventions to increase uptake of COVID-19 vaccines were searched for updated results. RESULTS: Results centre around two aspects of a vaccination campaign of interest to policymakers: communication and administration. Results suggest that communications highlighting the personal benefits of vaccination are likely to be more effective than those highlighting collective benefits. The efficacy of vaccination may be underestimated and stressing efficacy as a strong personal benefit may increase uptake. Keeping vaccines free, sending personalised messages, reminders and prebooked appointment times may also increase uptake. CONCLUSIONS: There is now a body of evidence from behavioural science that suggests how vaccination campaigns for COVID-19 can be structured to increase uptake. These recommendations may be useful to policymakers considering seasonal vaccination campaigns and to researchers generating hypotheses for country-specific trials.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Humanos , Vacunas contra la COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Vacunación , Comunicación , Gripe Humana/prevención & control
4.
Mol Phylogenet Evol ; 166: 107316, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34537324

RESUMEN

Marine species that are widely distributed in the Tropical Eastern Pacific (TEP) has served as a model for studying biogeographic patterns resulting from the effects of intraregional habitat discontinuities and oceanographic processes on the diversification and evolution of cryptobenthic reef fishes. Tomicodon petersii, a clingfish (Gobiesocidae) endemic to the TEP, is found on very shallow rocky reefs from central Mexico to northern Peru, and in the Cocos and Galapagos islands. We evaluated the effect of likely biogeographic barriers in different parts of the TEP on the diversification process of this species. We used one mitochondrial and three nuclear DNA markers from 112 individuals collected across the distribution range of T. petersii. Our phylogenetic results showed the samples constituted a monophyletic group, with three well-supported, allopatric subgroups: in the Mexican province, the Panamic province (from El Salvador to Ecuador), and the Galapagos Islands. The split between the Mexican and more southerly clades was estimated to occur at the end of the Miocene ca. 5.74 Mya, and the subsequent cladogenetic event separating the Galapagos population from the Panamic population at the junction of the Pliocene and Pleistocene, ca. 2.85 Mya. The species tree, Bayesian species delimitation tests (BPP), STACEY, and substantial genetic distances separating these three populations indicate that these three independent evolutionary units likely include two unnamed species. The cladogenetic events that promoted the formation of those genetically differentiated groups are consistent with disruptive effects on gene flow of habitat discontinuities and oceanographic processes along the mainland shoreline in the TEP and of ocean-island isolation, in conjunction with the species intrinsic life-history characteristics.


Asunto(s)
Peces , Especiación Genética , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Ecosistema , Peces/genética , Filogenia
5.
Mol Phylogenet Evol ; 173: 107496, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35569809

RESUMEN

The Panamic Clingfish Gobiesox adustus is widely distributed in the Tropical Eastern Pacific (TEP), from the central Gulf of California, Mexico to Ecuador, including the oceanic Revillagigedo Archipelago, and Isla del Coco. This cryptobenthic species is restricted to very shallow rocky-reef habitats. Here, we used one mitochondrial and three nuclear DNA markers from 155 individuals collected across the distribution range of the species in order to evaluate if geographically structured populations exist and to elucidate its evolutionary history. Phylogenetic analyses recovered a monophyletic group, with four well-supported, allopatric subgroups. Each subgroup corresponded to one of the following well-known biogeographic regions/provinces: 1) the Revillagigedo Archipelago, 2) the Cortez + Mexican provinces (Mexico), 3) the Panamic province (from El Salvador to Ecuador), and 4) Isla del Coco. A molecular-clock analysis showed a mean date for the divergence between clade I (the Revillagigedos and Cortez + Mexican provinces) and clade II (Panamic province and Isla del Coco) in the Pliocene, at ca. 5.33 Mya. Within clade I, the segregation between the Revillagigedos and Cortez + Mexican province populations was dated at ca. 1.18 Mya, during the Pleistocene. Within clade II, the segregation between samples of Isla del Coco and the Panamic province samples was dated at ca. 0.77 Mya, during the Pleistocene. The species tree, Bayesian species delimitation tests (BPP and STACEY), the ΦST, AMOVA, and the substantial genetic distances that exist between those four subgroups, indicate that they are independent evolutionary units. These cladogenetic events seem to be related to habitat discontinuities, and oceanographic and geological processes that produce barriers to gene flow for G. adustus, effects of which are enhanced by the intrinsic ecological characteristics of this species.


Asunto(s)
Evolución Biológica , Peces , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Peces/genética , Humanos , Filogenia , Filogeografía
6.
Phys Rev Lett ; 128(16): 162701, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35522496

RESUMEN

The ^{18}O(α,γ)^{22}Ne reaction is an essential part of a reaction chain that produces the ^{22}Ne(α,n)^{25}Mg neutron source for both the weak and main components of the slow neutron-capture process. At temperatures of stellar helium burning, the astrophysically relevant resonances in the ^{18}O(α,γ)^{22}Ne reaction that dominate the reaction rate occur at α particle energies E_{lab} of 472 and 569 keV. However, previous experiments have shown the strengths of these two resonances to be very weak, and only upper limits or partial resonance strengths could be obtained. This Letter reports the first direct measurement of the total resonance strength for the 472- and 569-keV resonances, 0.26±0.05 and 0.63±0.30 µeV, respectively. New resonance strengths for the resonances at α particle energies of 662.1, 749.9, and 767.6 keV are also provided. These results were achieved in an experiment optimized for background suppression and detection efficiency. The experiment was performed at the Sanford Underground Research Facility, in the 4850-foot underground cavity dedicated to the Compact Accelerator System for Performing Astrophysical Research. The experimental end station used the γ-summing High EffiCiency TOtal absorption spectrometeR. Compared to previous works, the results decrease the stellar reaction rate by as much as ≈46_{-11}^{+6}% in the relevant temperature range of stellar helium burning.

7.
Mol Phylogenet Evol ; 156: 107021, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33248204

RESUMEN

Nibblers (family Girellidae) are reef fishes that are mostly distributed in the Indo-Pacific, with one exception: Girella stuebeli, which is found in the Cabo Verde Archipelago, in the Atlantic Ocean. We capitalized on this unusual distribution to study the evolutionary history of the girellids, and determine the relationship between G. stuebeli and the remaining nibbler taxa. Based on thousands of genomic markers (RAD sequences), we identified the closest relatives of G. stuebeli as being a clade of three species endemic to the northwestern Pacific, restricted to the Sea of Japan and vicinity. This clade diverged from G. stuebeli approximately 2.2 Mya. Two alternative potential routes of migration may explain this affinity: a western route, from the Tropical Eastern Pacific and the Tropical Western Atlantic, and an eastern route via the Indian Ocean and Southern Africa. The geological history and oceanography of the regions combined with molecular data presented here, suggest that the eastern route of invasion (via the Indian Ocean and Southern Africa) is a more likely scenario.


Asunto(s)
Evolución Biológica , Arrecifes de Coral , Perciformes/fisiología , Animales , Océano Atlántico , Cabo Verde , Calibración , Geografía , Mitocondrias/genética , Océano Pacífico , Filogenia , ARN Ribosómico 16S/genética , Factores de Tiempo
8.
J Clin Lab Anal ; 35(10): e23955, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34424578

RESUMEN

BACKGROUND: Stored red blood cells (RBCs) may undergo oxidative stress over time, with functional changes affecting oxygen delivery. Central to these changes are oxidation-reduction (redox) reactions and redox potential (RP) that must be maintained for cell function. RP imbalance can lead to oxidative stress that may contribute to storage lesions. This study's purpose was to identify changes in RP over time in banked RBCs, and among RBCs of similar age. METHODS: Multiple random RBC segments from RBC units were tested (n = 32), ranging in age from 5 to 40 days, at 5-day intervals. RP was recorded by measuring open circuit potential of RBCs using nanoporous gold electrodes with Ag/AgCl reference. RP measures were also performed on peripheral venous blood from 10 healthy volunteers. RP measures were compared between RBC groups, and with volunteer blood. RESULTS: Stored RBCs show time-dependent RP increases. There were significant differences in Day 5 RP compared to all other groups (p ≤ 0.005), Day 10-15 vs. ages ≥ Day 20 (p ≤ 0.025), Day 20-25 vs. Day 40 (p = 0.039), and all groups compared to healthy volunteers. RP became more positive over time suggesting ongoing oxidation as RBCs age; however, storage time alone was not predictive of RP measured in a particular unit/segment. CONCLUSIONS: There are significant differences in RP between freshly stored RBCs and all others, with RP becoming more positive over time. However, storage time alone does not predict RP, indicating RP screening may be an important measure of RBC oxidative stress and serve as an RBC quality marker.


Asunto(s)
Conservación de la Sangre , Eritrocitos/fisiología , Estrés Oxidativo/fisiología , Bancos de Sangre , Transfusión de Eritrocitos , Humanos , Oxidación-Reducción
9.
Phys Rev Lett ; 125(6): 062501, 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32845657

RESUMEN

Precise antineutrino measurements are very sensitive to proper background characterization. We present an improved measurement of the ^{13}C(α,n)^{16}O reaction cross section which constitutes significant background for large ν[over ¯] detectors. We greatly improve the precision and accuracy by utilizing a setup that is sensitive to the neutron energies while making measurements of the excited state transitions via secondary γ-ray detection. Our results shows a 54% reduction in the background contributions from the ^{16}O(3^{-},6.13 MeV) state used in the KamLAND analysis.

10.
Gynecol Oncol ; 158(3): 681-688, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32571681

RESUMEN

OBJECTIVE: Population-based data on perioperative complications among women with endometrial cancer and severe obesity are lacking. We evaluated 30-day complication rates among women with and without class III obesity (body mass index ≥ 40 kg/m2) undergoing primary surgical management for endometrioid endometrial cancer (EEC), and how outcomes differed according to surgical approach (open vs. minimally invasive). METHODS: We performed a retrospective population-based cohort study of women with EEC undergoing hysterectomy in Ontario, Canada, between 2006 and 2015. We evaluated perioperative complications in the whole cohort, and in a 1:1 matched analysis using hard and propensity score matching to ensure similar distributions of patient, tumour, provider and institution-level factors between women with and without class III obesity (identified using a surgical billing code). The primary outcome of interest was the 30-day perioperative complication rate. RESULTS: 12,112 women met inclusion criteria; 2697 (22.3%) had class III obesity. We matched 2320 (86%) women with class III obesity to those without. The composite complication rate was significantly higher among women with class III obesity (23.2% vs. 18.4%, standardized mean difference [SMD] = 0.12), primarily due to wound infection/disruption (12.1% vs. 6.2%). There was no difference in outcomes for women with and without class III obesity when a minimally invasive approach was used. CONCLUSIONS: Wound infection/disruption was increased for women with class III obesity compared to women without. Otherwise, perioperative complications were similar between the matched pairs. When minimally invasive approaches were used, women with class III obesity had a similar risk of complications as women without obesity.


Asunto(s)
Carcinoma Endometrioide/epidemiología , Carcinoma Endometrioide/cirugía , Neoplasias Endometriales/cirugía , Obesidad/epidemiología , Anciano , Estudios de Cohortes , Femenino , Humanos , Histerectomía/efectos adversos , Histerectomía/estadística & datos numéricos , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/estadística & datos numéricos , Periodo Perioperatorio , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Resultado del Tratamiento
11.
J Intern Med ; 286(4): 438-448, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30861229

RESUMEN

BACKGROUND: Patients with postural tachycardia syndrome (POTS) experience chronic symptoms of orthostatic intolerance. There are minimal data detailing the demographics, clinical features and clinical course of this condition. This online, community-based survey highlights patients' experience with POTS. It consists of the largest sample of POTS patients reported to date. OBJECTIVES: To describe the demographics, past medical history, medications, treatments and diagnostic journey for patients living with POTS. METHODS: Postural tachycardia syndrome patients completed an online, community-based, cross-sectional survey. Participants were excluded if they had not received a diagnosis of POTS from a physician. The questions focused on the patient experience and journey, rather than physiological responses. RESULTS: The final analysis included 4835 participants. POTS predominantly affects white (93%) females (94%) of childbearing age, with approximately half developing symptoms in adolescence (mode 14 years). POTS is a chronic multisystem disorder involving a broad array of symptoms, with many patients diagnosed with comorbidities in addition to POTS. POTS patients often experience lengthy delays [median (interquartile range) 24 (6-72) months] and misdiagnosis, but the diagnostic delay is improving. POTS patients can present with a myriad of symptoms most commonly including lightheadedness (99%), tachycardia (97%), presyncope (94%), headache (94%) and difficulty concentrating (94%). CONCLUSIONS: These data provide important insights into the background, clinical features and diagnostic journey of patients suffering from POTS. These data should serve as an essential step for moving forward with future studies aimed at early and accurate diagnoses of these patients leading to appropriate treatments for their symptoms.


Asunto(s)
Síndrome de Taquicardia Postural Ortostática/psicología , Síndrome de Taquicardia Postural Ortostática/terapia , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome de Taquicardia Postural Ortostática/diagnóstico , Síndrome de Taquicardia Postural Ortostática/fisiopatología , Encuestas y Cuestionarios
12.
Mol Phylogenet Evol ; 130: 269-285, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30359746

RESUMEN

Habitat discontinuities, temperature gradients, upwelling systems, and ocean currents, gyres and fronts, can affect distributions of species with narrow environmental tolerance or motility and influence the dispersal of pelagic larvae, with effects ranging from the isolation of adjacent populations to connections between them. The coast of the Tropical Eastern Pacific (TEP) is a highly dynamic environment, with various large gyres and upwelling systems, alternating currents and large rocky-habitat discontinuities, which may greatly influence the genetic connectivity of populations in different parts of the coast. Elacatinus puncticulatus is a cryptic, shallow-living goby that is distributed along the continental shore of virtually the entire TEP, which makes it a good model for testing the influence of these environmental characteristics in the molecular evolution of widespread species in this region. A multilocus phylogeny was used to evaluate the influence of habitat gaps, and oceanographic processes in the evolutionary history of E. puncticulatus throughout its geographical range in the TEP. Two well-supported allopatric clades (one with two allopatric subclades) were recovered, the geographic distribution of which does not correspond to any previously proposed major biogeographic provinces. These populations show strong genetic structure and substantial genetic distances between clades and sub-clades (cytb 0.8-7.3%), with divergence times between them ranging from 0.53 to 4.88 Mya, and recent population expansions dated at 170-130 Kya. The ancestral area of all populations appears to be the Gulf of Panama, while several isolation events have formed the phylogeographic patterns evident in this species. Local and regional oceanographic processes as well as habitat discontinuities have shaped the distribution patterns of the genetic lineages along the continental TEP. Large genetic distances, high genetic differentiation, and the results of species-tree and phylogenetic analyses indicate that E. puncticulatus comprises a complex of three allopatric species with an unusual geographic arrangement.


Asunto(s)
Evolución Biológica , Ecosistema , Peces/fisiología , Clima Tropical , Animales , Teorema de Bayes , Bases de Datos Genéticas , Evolución Molecular , Haplotipos/genética , Océano Pacífico , Panamá , Filogenia , Filogeografía , Análisis de Secuencia de ADN , Especificidad de la Especie , Factores de Tiempo
13.
Transfusion ; 59(6): 2016-2022, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30758856

RESUMEN

BACKGROUND: The routine pretransfusion investigations in Southern Ghana involve only ABO-D blood group typing and ABO compatibility testing without screening for irregular red blood cell (RBC) antibodies. The prevalence and specificities of RBC antibodies and frequencies of most minor blood group antigens in transfused patients with sickle cell disease (SCD) in Ghana are not known and are the objectives of this study. STUDY DESIGN AND METHODS: This was a cross-sectional study that investigated transfused patients with SCD for the presence of irregular RBC antibodies and Rhesus, Kell, Duffy, Kidd, and Ss antigens. RESULTS: From a total of 154 patients (median age, 9 years), 10 patients (6.5%) possessed 13 antibodies, predominantly against D, C, and E antigens. In three patients, the antibodies (anti-D, anti-D + C, and anti-C + e) were against antigens they possessed by serology. Genotyping showed that two of these patients had variant RHCE genes that encode for weak and partial e antigens and one patient had a partial RHC gene. Frequencies of most RBC antigens were comparable with frequencies established among the African American population; however, K-k- and Jk(a-b-) phenotypes were more frequent and were present in 21% and 17% of patients, respectively. CONCLUSION: The prevalence of RBC alloimmunization in transfused Ghanaian patients with SCD was 6.5% and the majority of antibodies were against antigens of the Rh system. Our findings stress the need to include pretransfusion testing for RBC antibodies in patients with SCD, to improve transfusion safety.


Asunto(s)
Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/terapia , Antígenos de Grupos Sanguíneos/inmunología , Eritrocitos/inmunología , Isoanticuerpos/sangre , Adolescente , Adulto , Anemia Hemolítica Autoinmune/epidemiología , Anemia Hemolítica Autoinmune/etiología , Anemia de Células Falciformes/epidemiología , Anemia de Células Falciformes/inmunología , Incompatibilidad de Grupos Sanguíneos/epidemiología , Incompatibilidad de Grupos Sanguíneos/etiología , Incompatibilidad de Grupos Sanguíneos/inmunología , Transfusión Sanguínea/métodos , Transfusión Sanguínea/estadística & datos numéricos , Niño , Preescolar , Estudios Transversales , Transfusión de Eritrocitos/efectos adversos , Transfusión de Eritrocitos/estadística & datos numéricos , Femenino , Ghana/epidemiología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Fenotipo , Reacción a la Transfusión/epidemiología , Reacción a la Transfusión/etiología , Adulto Joven
14.
Biometrics ; 75(3): 885-894, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30714095

RESUMEN

Response-adaptive designs allow the randomization probabilities to change during the course of a trial based on cumulated response data so that a greater proportion of patients can be allocated to the better performing treatments. A major concern over the use of response-adaptive designs in practice, particularly from a regulatory viewpoint, is controlling the type I error rate. In particular, we show that the naïve z-test can have an inflated type I error rate even after applying a Bonferroni correction. Simulation studies have often been used to demonstrate error control but do not provide a guarantee. In this article, we present adaptive testing procedures for normally distributed outcomes that ensure strong familywise error control by iteratively applying the conditional invariance principle. Our approach can be used for fully sequential and block randomized trials and for a large class of adaptive randomization rules found in the literature. We show there is a high price to pay in terms of power to guarantee familywise error control for randomization schemes with extreme allocation probabilities. However, for proposed Bayesian adaptive randomization schemes in the literature, our adaptive tests maintain or increase the power of the trial compared to the z-test. We illustrate our method using a three-armed trial in primary hypercholesterolemia.


Asunto(s)
Ensayos Clínicos Adaptativos como Asunto/métodos , Modelos Estadísticos , Proyectos de Investigación , Sesgo , Simulación por Computador , Humanos , Hipercolesterolemia/terapia , Distribución Aleatoria
15.
Mol Phylogenet Evol ; 121: 35-45, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29289544

RESUMEN

The New World Halichoeres comprises about 30 small to medium sized wrasse species that are prominent members of reef communities throughout the tropical Western Atlantic and Eastern Pacific. We conducted a phylogenetic analysis of this group and related lineages using new and previously published sequence data. We estimated divergence times, evaluated the monophyly of this group, their relationship to other labrids, as well as the time-course and geography of speciation. These analyses show that all members of New World Halichoeres form a monophyletic group that includes Oxyjulis and Sagittalarva. New World Halichoeres is one of numerous labrid groups that appear to have radiated rapidly about 32 Ma and form a large polytomy within the julidine wrasses. We reconstruct the tropical Western Atlantic to be the ancestral area of New World Halichoeres, with four invasions of the Eastern Pacific and one reversal from East Pacific to Western Atlantic. These five speciation events were spread across the history of the group, with none corresponding closely to the time of the closure of the Isthmus of Panama. Three speciation events within the Atlantic occurred across the Orinoco-Amazon outflow and within the Pacific, five involve splits between lineages that occupy coastal reef systems and offshore islands. Of eight sister species pairs, seven show complete allopatry and one is fully sympatric.


Asunto(s)
Especiación Genética , Geografía , Perciformes/clasificación , Perciformes/genética , Filogenia , Animales , Teorema de Bayes , Ecosistema , Modelos Biológicos , Panamá , Filogeografía , Especificidad de la Especie , Factores de Tiempo
16.
Int J Dent Hyg ; 16(1): 68-77, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28544259

RESUMEN

OBJECTIVES: To review the evidence for the efficacy of periodontal maintenance (PM) carried out in primary dental care (PDC) compared to the specialist setting for patients previously treated in a specialist setting for chronic (ChP) or aggressive (AgP) periodontitis. METHODS: A focused PICO question and search protocol were developed. Online databases including MEDLINE, EMBASE, WEB OF SCIENCE™ and COCHRANE LIBRARY were searched along with specialist journals in the subject area of periodontal research. Selection criteria included studies that investigated delivery of PM in both specialist and PDC settings for patients with ChP or AgP over a minimum 12 months. We looked for studies that reported changes in clinical attachment levels (CAL), tooth loss, pocket probing depths (PPDs) and bleeding on probing (BoP) as outcome measures. RESULTS: Eight cohort studies were chosen for inclusion. There was considerable heterogeneity found between the eight studies, which did not allow for quantitative (meta) analysis and statistical testing of differences between groups. Clinical attachment levels remained relatively stable in patients who received specialist PM with mean changes of -0.42 mm to +0.2 mm, while for those enrolled in PDC-based PM for periods >12 months, mean CAL losses were between -0.13 mm and -2.80 mm. PPD reduction for those subjects receiving specialist PM was between 0.05 and 1.8 mm for five studies but two cohorts experienced increases of 0.32 and 0.80 mm, respectively. Increases of up to 2.90 mm (range: -0.1 to +2.90) and a higher proportion of deeper pockets were noted among PDC PM cohorts. Higher rates of BoP among those in receipt of PDC PM were reported in half of all studies. There were insufficient long-term data to make any firm conclusions about the effect of the delivery of PM on tooth loss. CONCLUSION: Within the limitations of the data available, it appears that specialist PM is effective in sustaining periodontal stability following active specialist intervention. There is limited evidence that PDC provides the same level of care; however, the limited comparative data available suggest that outcomes could be slightly worse in PDC.


Asunto(s)
Continuidad de la Atención al Paciente , Atención Odontológica , Periodoncia , Periodontitis/terapia , Humanos
17.
Mol Pharm ; 14(1): 172-182, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-28043127

RESUMEN

Sickle cell disease (SCD) is a genetic blood disorder that affects the shape and transportation of red blood cells (RBCs) in blood vessels, leading to various clinical complications. Many drugs that are available for treating the disease are insufficiently effective, toxic, or too expensive. Therefore, there is a pressing need for safe, effective, and inexpensive therapeutic agents from indigenous plants used in ethnomedicines. The potential of aqueous extracts of Cajanus cajan leaf and seed, Zanthoxylum zanthoxyloides leaf, and Carica papaya leaf in sickle cell disease management was investigated in vitro using freshly prepared 2% sodium metabisulfite for sickling induction. The results indicated that the percentage of sickled cells, which was initially 91.6% in the control, was reduced to 29.3%, 41.7%, 32.8%, 38.2%, 47.6%, in the presence of hydroxyurea, C. cajan seed, C. cajan leaf, Z. zanthoxyloides leaf, and C. papaya leaf extracts, respectively, where the rate of polymerization inhibition was 6.5, 5.9, 8.0, 6.6, and 6.0 (×10-2) accordingly. It was also found that the RBC resistance to hemolysis was increased in the presence of the tested agents as indicated by the reduction of the percentage of hemolyzed cells from 100% to 0%. The phytochemical screening results indicated the presence of important phytochemicals including tannins, saponins, alkaloids, flavonoids, and glycosides in all the plant extracts. Finally, gas chromatography-mass spectrometry analysis showed the presence of important secondary metabolites in the plants. These results suggest that the plant extracts have some potential to be used as alternative antisickling therapy to hydroxyurea in SCD management.


Asunto(s)
Antidrepanocíticos/farmacología , Extractos Vegetales/farmacología , Alcaloides/química , Alcaloides/farmacología , Anemia de Células Falciformes/tratamiento farmacológico , Antidrepanocíticos/química , Cajanus/química , Carica/química , Eritrocitos/efectos de los fármacos , Flavonoides/química , Flavonoides/farmacología , Glicósidos/química , Glicósidos/farmacología , Humanos , Medicina Tradicional/métodos , Fitoquímicos/química , Fitoquímicos/farmacología , Extractos Vegetales/química , Hojas de la Planta/química , Saponinas/química , Saponinas/farmacología , Semillas/química , Taninos/química , Taninos/farmacología , Zanthoxylum/química
18.
Mol Ecol ; 25(15): 3662-82, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27222496

RESUMEN

Mesophotic and deeper reefs of the tropics are poorly known and underexplored ecosystems worldwide. Collectively referred to as the 'twilight zone', depths below ~30-50 m are home to many species of reef fishes that are absent from shallower depths, including many undescribed and endemic species. We currently lack even a basic understanding of the diversity and evolutionary origins of fishes on tropical mesophotic reefs. Recent submersible collections in the Caribbean have provided new specimens that are enabling phylogenetic reconstructions that incorporate deep-reef representatives of tropical fish genera. Here, we investigate evolutionary depth transitions in the family Gobiidae (gobies), the most diverse group of tropical marine fishes. Using divergence-time estimation coupled with stochastic character mapping to infer the timing of shallow-to-deep habitat transitions in gobies, we demonstrate at least four transitions from shallow to mesophotic depths. Habitat transitions occurred in two broad time periods (Miocene, Pliocene-Pleistocene), and may have been linked to the availability of underutilized niches, as well as the evolution of morphological/behavioural adaptations for life on deep reefs. Further, our analysis shows that at least three evolutionary lineages that invaded deep habitats subsequently underwent speciation, reflecting another unique mode of radiation within the Gobiidae. Lastly, we synthesize depth distributions for 95 species of Caribbean gobies, which reveal major bathymetric faunal breaks at the boundary between euphotic and mesophotic reefs. Ultimately, our study is the first rigorous investigation into the origin of Caribbean deep-reef fishes and provides a framework for future studies that utilize rare, deep-reef specimens.


Asunto(s)
Evolución Biológica , Arrecifes de Coral , Peces/clasificación , Animales , Región del Caribe , Especiación Genética , Filogenia
19.
Psychol Med ; 46(12): 2595-604, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27353452

RESUMEN

BACKGROUND: Many adults with autism spectrum disorder (ASD) remain undiagnosed. Specialist assessment clinics enable the detection of these cases, but such services are often overstretched. It has been proposed that unnecessary referrals to these services could be reduced by prioritizing individuals who score highly on the Autism-Spectrum Quotient (AQ), a self-report questionnaire measure of autistic traits. However, the ability of the AQ to predict who will go on to receive a diagnosis of ASD in adults is unclear. METHOD: We studied 476 adults, seen consecutively at a national ASD diagnostic referral service for suspected ASD. We tested AQ scores as predictors of ASD diagnosis made by expert clinicians according to International Classification of Diseases (ICD)-10 criteria, informed by the Autism Diagnostic Observation Schedule-Generic (ADOS-G) and Autism Diagnostic Interview-Revised (ADI-R) assessments. RESULTS: Of the participants, 73% received a clinical diagnosis of ASD. Self-report AQ scores did not significantly predict receipt of a diagnosis. While AQ scores provided high sensitivity of 0.77 [95% confidence interval (CI) 0.72-0.82] and positive predictive value of 0.76 (95% CI 0.70-0.80), the specificity of 0.29 (95% CI 0.20-0.38) and negative predictive value of 0.36 (95% CI 0.22-0.40) were low. Thus, 64% of those who scored below the AQ cut-off were 'false negatives' who did in fact have ASD. Co-morbidity data revealed that generalized anxiety disorder may 'mimic' ASD and inflate AQ scores, leading to false positives. CONCLUSIONS: The AQ's utility for screening referrals was limited in this sample. Recommendations supporting the AQ's role in the assessment of adult ASD, e.g. UK NICE guidelines, may need to be reconsidered.


Asunto(s)
Trastorno del Espectro Autista/diagnóstico , Escalas de Valoración Psiquiátrica/normas , Autoinforme/normas , Encuestas y Cuestionarios/normas , Adulto , Trastorno del Espectro Autista/epidemiología , Comorbilidad , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Adulto Joven
20.
Transfusion ; 56(12): 3073-3080, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27601087

RESUMEN

BACKGROUND: Therapeutic plasma exchange (TPE) is increasingly used for treatment of antibody-mediated rejection (AMR) after solid organ transplants. There is concern that TPE may increase risk of bleeding, although data are limited. After TPE, clot-based coagulation tests may not accurately represent the levels of coagulation factors due to the effect of citrate. We investigated protein levels of fibrinogen using antigen detection method (FibAg) and correlated results with a clot-based fibrinogen activity test (Fib). STUDY DESIGN AND METHODS: Nine kidney transplant recipients who received TPE for AMR were investigated. Fib, FibAg, prothrombin time/international normalized ratio (PT/INR), partial thromboplastin time (PTT), coagulation factor X chromogenic activity (CFX), and ionized calcium (iCa) were measured at pre- and post-TPE and 1, 3, 6, 9, 24, and 48 hours after the first TPE. RESULTS: Mean Fib/FibAg ratio before TPE was 1.08; therefore, all Fib values were normalized (n) by dividing by 1.08. Overall, the mean normalized Fib (nFib)/FibAg ratio at post-TPE was 0.89 and returned to close to 1.0 at 6 hours after the first TPE. Decreases in nFib, FibAg, and CFX and increases in PT/INR and PTT post-TPE were observed. The lowest Fib, FibAg, CFX, platelet, and iCa levels were still at levels that would be considered sufficient for hemostasis at all time points. CONCLUSION: The mean nFib/FibAg ratio after TPE was 0.89 and normalized in 6 hours, which demonstrates a persistent effect of citrate for up to 6 hours. Therefore, similar data observed in clot-based tests of PT/INR and PTT may be falsely elevated up to 6 hours after TPE due to the citrate effect.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Ácido Cítrico/farmacología , Trasplante de Riñón/efectos adversos , Intercambio Plasmático/efectos adversos , Pruebas de Coagulación Sanguínea/normas , Fibrinógeno/análisis , Hemostasis/efectos de los fármacos , Humanos , Factores de Tiempo
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