2,501 research outputs found
Chromosome-scale assembly of the coral endosymbiont Symbiodinium microadriaticum genome provides insight into the unique biology of dinoflagellate chromosomes [preprint]
Dinoflagellates are major primary producers in the world’s oceans, the cause of harmful algal blooms, and endosymbionts of marine invertebrates. Much remains to be understood about their biology including their peculiar crystalline chromosomes. Here we used Hi-C to order short read-based sub-scaffolds into 94 chromosome-scale scaffolds of the genome of the coral endosymbiont Symbiodinium microadriaticum. Hi-C data show that chromosomes are folded as linear rods within which loci separated by up to several Mb are highly packed. Each chromosome is composed of a series of structural domains separated by boundaries. Genes are enriched towards the ends of chromosomes and are arranged in unidirectional blocks that alternate between top and bottom strands. Strikingly, the boundaries of chromosomal domains are positioned at sites where transcription of two gene blocks converges, indicating a correlation between gene orientation, transcription and chromosome folding. Some chromosomes are enriched for genes involved in specific biological processes (e.g., photosynthesis, and nitrogen-cycling), and functionally related genes tend to co-occur at adjacent sites in the genome. All chromosomes contain several repeated segments that are enriched in mobile elements. The assembly of the S. microadriaticum genome and initial description of its genetic and spatial organization provide a foundation for deeper exploration of the extraordinary biology of dinoflagellates and their chromosomes
Predictive modeling, geographic distribution and conservation status of Tomopeas ravus Miller, 1900 (Chiroptera, Molossidae)
Tomopeas ravus, el murciélago de orejas romas, se conoce solo de 13 localidades confirmadas en Perú y actualmente se encuentra listada como En Peligro (B2 ab (iii)) por la UICN. La distribución, extensión de ocurrencia y el área de vida de esta especie no han sido esclarecidos completamente. Presentamos el primer modelo predictivo basado en los registros conocidos y el primer acercamiento geográfico para la especie. Basados en los 13 registros confirmados se construyó un modelo de hábitat de máxima entropÃa determinando previamente las variables ambientales de mayor importancia para el modelo. Se estimó un Ãndice predictivo aceptable (0.970) para el modelo final. Se determinó las zonas de mayor probabilidad de ocurrencia para esta especie y se estimó el área de distribución mediante el método del polÃgono mÃnimo convexo (PMC). El área prioritaria más importante identificada para la conservación de esta especie se sitúa al norte de Perú, entre los Departamentos de Tumbes y Piura. Se recomienda utilizar el presente modelo como herramienta útil para futuras evaluaciones de la conservación de esta especie.Tomopeas ravus, known as blunt - eared bat, is known only from thirteen confirmed localities in Peru and is currently listed as Endangered (B2 ab (iii)) by the IUCN. The distribution, occurrence extension and home range of this species is not have been completely clarified. We presents the first predictive model based on the known records and the first geographic approach to this species. On the basis of thirteen confirmed records we built a habitat model of maximum entropy determining previously the most important environmental variables for the model. An acceptable predictive index (0.970) was obtained for the final model. We determined the areas of major probability of occurrence for this species and felt the geographic distribution through the method of the polygon mÃnimum convex (PMC). The priority area identified for the conservation of this species is located in the northern of Peru, between the Departments of Tumbes and Piura. We recommended to use the present model as a useful tool for future evaluations of conservation of this species
Delta de hemoglobina materna entre el primer y tercer trimestre como factor de riesgo para bajo peso al nacer: Un estudio de cohorte
Objetive: The present study focused on determining if the hemoglobin difference of the third and first trimester of gestation greater than - 1 (decreased hemoglobin delta) is a risk factor for low birth weight in term newborns at Hospital Belen from Trujillo. Material and Methods: We performed a retrospective cohort study in which 218 newborns were included according to the selection criteria. The patients were divided into two group of patients with decreased and non-decreased maternal hemoglobin delta: applying the relative risk and the statistical chi test-square. Results: The frequency of low birth weight in pregnant women with decreased hemoglobin delta was 32/109 = 29%; the frequency of low birth weight in pregnant women with undiminished delta hemoglobin was 18/109 = 17%. Declined maternal hemoglobin delta is a risk factor for low birth weight with a relative risk of 1.78 [CI: 95% (1.45 - 3.56) p <0.05]. Conclusions: The decreased maternal hemoglobin delta is a risk factor for low birth weight in newborns at Hospital Belen de Trujillo.Objetivo: El presente estudio se centró en determinar si la diferencia de hemoglobina del tercer y el primer trimestre de gestación mayor de – 1 (Delta de hemoglobina disminuido) es un factor de riesgo para el bajo peso al nacer en recién nacidos a término en el Hospital Belén de Trujillo. Material y métodos: Estudio de cohorte histórica. Se realizó un estudio de cohorte retrospectiva donde se incluyeron 218 neonatos, de acuerdo con los criterios de selección, los cuales fueron divididos en dos grupos: pacientes con delta de hemoglobina materna disminuida y no disminuida: aplicando el riesgo relativo y el test estadÃstico de chi-cuadrado. Resultados: La frecuencia de neonatos con bajo peso al nacer en mujeres embarazadas con delta de hemoglobina disminuida fue de 32/109 = 29 %; la frecuencia de bajo peso al nacer en las mujeres embarazadas con delta de hemoglobina no disminuida fue de 18/109 = 17 %. La delta de hemoglobina materna disminuida es un factor de riesgo para el bajo peso al nacer con un riesgo relativo de 1.78 [IC: 95 % (1.45 – 3.56) p < 0.05]. Conclusiones: La delta de hemoglobina materna disminuida es un factor de riesgo para el bajo peso al nacer en recién nacidos a término en el Hospital Belén de Trujillo
Syndrome of hiperinfection by Strongyloides stercoralis
Se presenta el caso de una estrongiloidiasis diseminada en una paciente con tratamiento crónico de corticoides y una tumoración en región bulbar, que cursa con sÃndrome de distrés respiratorio agudo y lesiones dérmicas, aislándose la larva en el aspirado de secresión bronquial y biopsia de piel.It is showed a disseminated strongyloidiasis in a patient under chronic treatment with corticosteroids and a bulbar tumor, with acute respiratory distress syndrome and skin lesions, and isolation of the larva in bronchial secretion aspirate and skin biopsy
The Role of Stress in Understanding Differences in Sedentary Behavior in Hispanic/Latino Adults: Results from the Hispanic Community Health Study/Study of Latinos Sociocultural Ancillary Study
Chronic stress and/or lifetime traumatic stress can create a self-reinforcing cycle of unhealthy behaviors, such as overeating and sedentary behavior, that can lead to further increases in stress. This study examined the relationship between stress and sedentary behavior in a sample of Hispanic/Latino adults (N = 4244) from the Hispanic Community Health Study/Study of Latinos Sociocultural Ancillary Study
Grade V small bowel injury after blunt abdominal trauma: a case report
Injury of the small intestine or mesentery that requires surgical intervention is relatively uncommon, presenting less than 1% of all trauma. Unstable hemodynamically patients with peritoneal irritation signs and stable hemodynamically patients with radiological signs of intestine or mesentery lesions need an exploratory laparotomy. A 33-year-old male patient, suffered a car accident in which he had a frontal impact collision and was between two structures for 30 minutes, and rescued by the fire department. Physical examination of the abdomen presents generalized pain on palpation of moderate intensity and rebound sign. An exploratory laparotomy was performed, the findings were: hemoperitoneum of 1500 ml was found, lesion in the bucket loop of 1.2 meters, 1.8 meters from the Treitz angle and 70 cm from the ileocecal valve. We managed with drainage, vascular control, resection of the devascularized intestinal loop and small bowel shotgun stoma were. The patient was transferred to the intensive care unit for hemodynamic management and a second look was performed 5 days after surgery where cavity lavage, stoma dismantling and end-to-end anastomosis of the small intestine in two planes were performed. On post-operative day 7 drains were removed, and the patient was discharged from the surgical service due to improvement, without complications. We recommend a multidisciplinary approach to patients with polytrauma, since they lead to a better and faster recovery, in the same way it allows us to detect and treat any abnormality that impacts the quality of life of patients early
Genome-wide association study of dental caries in the Hispanic Communities Health Study/Study of Latinos (HCHS/SOL)
Dental caries is the most common chronic disease worldwide, and exhibits profound disparities in the USA with racial and ethnic minorities experiencing disproportionate disease burden. Though heritable, the specific genes influencing risk of dental caries remain largely unknown. Therefore, we performed genome-wide association scans (GWASs) for dental caries in a population-based cohort of 12 000 Hispanic/Latino participants aged 18–74 years from the HCHS/SOL. Intra-oral examinations were used to generate two common indices of dental caries experience which were tested for association with 27.7 M genotyped or imputed single-nucleotide polymorphisms separately in the six ancestry groups. A mixed-models approach was used, which adjusted for age, sex, recruitment site, five principal components of ancestry and additional features of the sampling design. Meta-analyses were used to combine GWAS results across ancestry groups. Heritability estimates ranged from 20–53% in the six ancestry groups. The most significant association observed via meta-analysis for both phenotypes was in the region of the NAMPT gene (rs190395159; P-value = 6 × 10−10), which is involved in many biological processes including periodontal healing. Another significant association was observed for rs72626594 (P-value = 3 × 10−8) downstream of BMP7, a tooth development gene. Other associations were observed in genes lacking known or plausible roles in dental caries. In conclusion, this was the largest GWAS of dental caries, to date and was the first to target Hispanic/Latino populations. Understanding the factors influencing dental caries susceptibility may lead to improvements in prediction, prevention and disease management, which may ultimately reduce the disparities in oral health across racial, ethnic and socioeconomic strata
History of Periodontitis Diagnosis and Edentulism as Predictors of Cardiovascular Disease, Stroke, and Mortality in Postmenopausal Women
BACKGROUND: Few studies have reported associations between periodontitis and cardiovascular disease (CVD) risk in older women, which is the objective of the present investigation.
METHODS AND RESULTS: Participants were 57 001 postmenopausal women ages 55 to 89 years (mean 68 years; \u3e 85% 60 and older) who were enrolled (1993-1998) in the Women\u27s Health Initiative Observational Study, and were without known CVD when history of periodontitis and edentulism was assessed by questionnaire at study Year-5 (1998-2003). There were 3589 incident CVD events and 3816 total deaths during a mean follow-up of 6.7 years. In multivariable analysis, periodontitis was not associated with CVD events, but was associated with higher total mortality (hazard ratio (HR)=1.12, 95% CI: 1.05-1.21). Edentulism was associated with higher age- and smoking-adjusted risks of CVD (HR=1.42, 95% CI: 1.27-1.59) and mortality (HR=1.47, 95% CI: 1.32-1.63). Further adjustment eliminated the association with CVD, but mortality remained significantly increased (HR=1.17, 95% CI: 1.02-1.33). Stratification on age, race-ethnicity, smoking, and diabetes mellitus yielded comparable results; however, edentulism was more strongly associated with CVD in women reporting \u3e /=1 dental visit (HR=1.57) compared with (HR 1.03, interaction P=0.004) annually.
CONCLUSIONS: In community-dwelling older women, edentulism was associated with increased risks of CVD and total mortality, and presence of periodontitis, which is more prevalent than edentulism, was associated with 17% higher mortality rate. These findings suggest that improving periodontal condition of the general population could reduce overall mortality
Direct venous inoculation of Plasmodium falciparum sporozoites for controlled human malaria infection: a dose-finding trial in two centres
BACKGROUND: Controlled human malaria infection (CHMI)
accelerates development of anti-malarial interventions. So far,
CHMI is done by exposure of volunteers to bites of five
mosquitoes carrying Plasmodium falciparum sporozoites (PfSPZ), a
technique available in only a few centres worldwide.
Mosquito-mediated CHMI is logistically complex, exact PfSPZ
dosage is impossible and live mosquito-based interventions are
not suitable for further clinical development. METHODS: An
open-labelled, randomized, dose-finding study in 18-45 year old,
healthy, malaria-naive volunteers was performed to assess if
intravenous (IV) injection of 50 to 3,200 aseptic, purified,
cryopreserved PfSPZ is safe and achieves infection kinetics
comparable to published data of mosquito-mediated CHMI. An
independent study site verified the fully infectious dose using
direct venous inoculation of PfSPZ. Parasite kinetics were
assessed by thick blood smear microscopy and quantitative real
time PCR. RESULTS: IV inoculation with 50, 200, 800, or 3,200
PfSPZ led to parasitaemia in 1/3, 1/3, 7/9, and 9/9 volunteers,
respectively. The geometric mean pre-patent period (GMPPP) was
11.2 days (range 10.5-12.5) in the 3,200 PfSPZ IV group.
Subsequently, six volunteers received 3,200 PfSPZ by direct
venous inoculation at an independent investigational site. All
six developed parasitaemia (GMPPP: 11.4 days, range: 10.4-12.3).
Inoculation of PfSPZ was safe. Infection rate and pre-patent
period depended on dose, and injection of 3,200 PfSPZ led to a
GMPPP similar to CHMI with five PfSPZ-infected mosquitoes. The
infectious dose of PfSPZ predicted dosage of
radiation-attenuated PfSPZ required for successful vaccination.
CONCLUSIONS: IV inoculation of PfSPZ is safe, well tolerated and
highly reproducible. It shall further accelerate development of
anti-malarial interventions through standardization and
facilitation of CHMI. Beyond this, rational dose selection for
whole PfSPZ-based immunization and complex study designs are now
possible. TRIAL REGISTRATION: ClinicalTrials.gov NCT01624961 and
NCT01771848
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