58 research outputs found

    Ectodermal Influx and Cell Hypertrophy Provide Early Growth for All Murine Mammary Rudiments, and Are Differentially Regulated among Them by Gli3

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    Mammary gland development starts in utero with one or several pairs of mammary rudiments (MRs) budding from the surface ectodermal component of the mammalian embryonic skin. Mice develop five pairs, numbered MR1 to MR5 from pectoral to inguinal position. We have previously shown that Gli3Xt-J/Xt-J mutant embryos, which lack the transcription factor Gli3, do not form MR3 and MR5. We show here that two days after the MRs emerge, Gli3Xt-J/Xt-J MR1 is 20% smaller, and Gli3Xt-J/Xt-J MR2 and MR4 are 50% smaller than their wild type (wt) counterparts. Moreover, while wt MRs sink into the underlying dermis, Gli3Xt-J/Xt-J MR4 and MR2 protrude outwardly, to different extents. To understand why each of these five pairs of functionally identical organs has its own, distinct response to the absence of Gli3, we determined which cellular mechanisms regulate growth of the individual MRs, and whether and how Gli3 regulates these mechanisms. We found a 5.5 to 10.7-fold lower cell proliferation rate in wt MRs compared to their adjacent surface ectoderm, indicating that MRs do not emerge or grow via locally enhanced cell proliferation. Cell-tracing experiments showed that surface ectodermal cells are recruited toward the positions where MRs emerge, and contribute to MR growth during at least two days. During the second day of MR development, peripheral cells within the MRs undergo hypertrophy, which also contributes to MR growth. Limited apoptotic cell death counterbalances MR growth. The relative contribution of each of these processes varies among the five MRs. Furthermore, each of these processes is impaired in the absence of Gli3, but to different extents in each MR. This differential involvement of Gli3 explains the variation in phenotype among Gli3Xt-J/Xt-J MRs, and may help to understand the variation in numbers and positions of mammary glands among mammals

    Sex differences in cardiovascular complications and mortality in hospital patients with covid-19: registry based observational study

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    Objective To assess whether the risk of cardiovascular complications of covid-19 differ between the sexes and to determine whether any sex differences in risk are reduced in individuals with pre-existing cardiovascular disease. Design Registry based observational study. Setting 74 hospitals across 13 countries (eight European) participating in CAPACITY-COVID (Cardiac complicAtions in Patients With SARS Corona vIrus 2 regisTrY), from March 2020 to May 2021 Participants All adults (aged ≄18 years), predominantly European, admitted to hospital with highly suspected covid-19 disease or covid-19 disease confirmed by positive laboratory test results (n=11 167 patients). Main outcome measures Any cardiovascular complication during admission to hospital. Secondary outcomes were in-hospital mortality and individual cardiovascular complications with ≄20 events for each sex. Logistic regression was used to examine sex differences in the risk of cardiovascular outcomes, overall and grouped by pre-existing cardiovascular disease. Results Of 11 167 adults (median age 68 years, 40% female participants) included, 3423 (36% of whom were female participants) had pre-existing cardiovascular disease. In both sexes, the most common cardiovascular complications were supraventricular tachycardias (4% of female participants, 6% of male participants), pulmonary embolism (3% and 5%), and heart failure (decompensated or de novo) (2% in both sexes). After adjusting for age, ethnic group, pre-existing cardiovascular disease, and risk factors for cardiovascular disease, female individuals were less likely than male individuals to have a cardiovascular complication (odds ratio 0.72, 95% confidence interval 0.64 to 0.80) or die (0.65, 0.59 to 0.72). Differences between the sexes were not modified by pre-existing cardiovascular disease; for the primary outcome, the female-to-male ratio of the odds ratio in those without, compared with those with, pre-existing cardiovascular disease was 0.84 (0.67 to 1.07). Conclusions In patients admitted to hospital for covid-19, female participants were less likely than male participants to have a cardiovascular complication. The differences between the sexes could not be attributed to the lower prevalence of pre-existing cardiovascular disease in female individuals. The reasons for this advantage in female individuals requires further research

    American palm ethnomedicine: A meta-analysis

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    <p>Abstract</p> <p>Background</p> <p>Many recent papers have documented the phytochemical and pharmacological bases for the use of palms (<it>Arecaceae</it>) in ethnomedicine. Early publications were based almost entirely on interviews that solicited local knowledge. More recently, ethnobotanically guided searches for new medicinal plants have proven more successful than random sampling for identifying plants that contain biodynamic ingredients. However, limited laboratory time and the high cost of clinical trials make it difficult to test all potential medicinal plants in the search for new drug candidates. The purpose of this study was to summarize and analyze previous studies on the medicinal uses of American palms in order to narrow down the search for new palm-derived medicines.</p> <p>Methods</p> <p>Relevant literature was surveyed and data was extracted and organized into medicinal use categories. We focused on more recent literature than that considered in a review published 25 years ago. We included phytochemical and pharmacological research that explored the importance of American palms in ethnomedicine.</p> <p>Results</p> <p>Of 730 species of American palms, we found evidence that 106 species had known medicinal uses, ranging from treatments for diabetes and leishmaniasis to prostatic hyperplasia. Thus, the number of American palm species with known uses had increased from 48 to 106 over the last quarter of a century. Furthermore, the pharmacological bases for many of the effects are now understood.</p> <p>Conclusions</p> <p>Palms are important in American ethnomedicine. Some, like <it>Serenoa repens </it>and <it>Roystonea regia</it>, are the sources of drugs that have been approved for medicinal uses. In contrast, recent ethnopharmacological studies suggested that many of the reported uses of several other palms do not appear to have a strong physiological basis. This study has provided a useful assessment of the ethnobotanical and pharmacological data available on palms.</p

    A systematic review of the psychometric properties of self-report research utilization measures used in healthcare

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    <p>Abstract</p> <p>Background</p> <p>In healthcare, a gap exists between what is known from research and what is practiced. Understanding this gap depends upon our ability to robustly measure research utilization.</p> <p>Objectives</p> <p>The objectives of this systematic review were: to identify self-report measures of research utilization used in healthcare, and to assess the psychometric properties (acceptability, reliability, and validity) of these measures.</p> <p>Methods</p> <p>We conducted a systematic review of literature reporting use or development of self-report research utilization measures. Our search included: multiple databases, ancestry searches, and a hand search. Acceptability was assessed by examining time to complete the measure and missing data rates. Our approach to reliability and validity assessment followed that outlined in the <it>Standards for Educational and Psychological Testing</it>.</p> <p>Results</p> <p>Of 42,770 titles screened, 97 original studies (108 articles) were included in this review. The 97 studies reported on the use or development of 60 unique self-report research utilization measures. Seven of the measures were assessed in more than one study. Study samples consisted of healthcare providers (92 studies) and healthcare decision makers (5 studies). No studies reported data on acceptability of the measures. Reliability was reported in 32 (33%) of the studies, representing 13 of the 60 measures. Internal consistency (Cronbach's Alpha) reliability was reported in 31 studies; values exceeded 0.70 in 29 studies. Test-retest reliability was reported in 3 studies with Pearson's <it>r </it>coefficients > 0.80. No validity information was reported for 12 of the 60 measures. The remaining 48 measures were classified into a three-level validity hierarchy according to the number of validity sources reported in 50% or more of the studies using the measure. Level one measures (n = 6) reported evidence from any three (out of four possible) <it>Standards </it>validity sources (which, in the case of single item measures, was all applicable validity sources). Level two measures (n = 16) had evidence from any two validity sources, and level three measures (n = 26) from only one validity source.</p> <p>Conclusions</p> <p>This review reveals significant underdevelopment in the measurement of research utilization. Substantial methodological advances with respect to construct clarity, use of research utilization and related theory, use of measurement theory, and psychometric assessment are required. Also needed are improved reporting practices and the adoption of a more contemporary view of validity (<it>i.e.</it>, the <it>Standards</it>) in future research utilization measurement studies.</p

    Landslide initiation and runout susceptibility modeling in the context of hill cutting and rapid urbanization: a combined approach of weights of evidence and spatial multi-criteria

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    Rainfall induced landslides are a common threat to the communities living on dangerous hill-slopes in Chittagong Metropolitan Area, Bangladesh. Extreme population pressure, indiscriminate hill cutting, increased precipitation events due to global warming and associated unplanned urbanization in the hills are exaggerating landslide events. The aim of this article is to prepare a scientifically accurate landslide susceptibility map by combining landslide initiation and runout maps. Land cover, slope, soil permeability, surface geology, precipitation, aspect, and distance to hill cut, road cut, drainage and stream network factor maps were selected by conditional independence test. The locations of 56 landslides were collected by field surveying. A weight of evidence (WoE) method was applied to calculate the positive (presence of landslides) and negative (absence of landslides) factor weights. A combination of analytical hierarchical process (AHP) and fuzzy membership standardization (weighs from 0 to 1) was applied for performing a spatial multi-criteria evaluation. Expert opinion guided the decision rule for AHP. The Flow-R tool that allows modeling landslide runout from the initiation sources was applied. The flow direction was calculated using the modified Holmgren’s algorithm. The AHP landslide initiation and runout susceptibility maps were used to prepare a combined landslide susceptibility map. The relative operating characteristic curve was used for model validation purpose. The accuracy of WoE, AHP, and combined susceptibility map was calculated 96%, 97%, and 98%, respectively

    New Measurement of Antineutrino Oscillation with the Full Detector Configuration at Daya Bay

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    Estimasi Cadangan Karbon pada Sedimen di Ekosistem Lamun Desa Pejarakan, Bali

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    Pemanasan global merupakan isu yang sedang hangat diperbincangkan. Dampak yang ditimbulkan oleh pemanasan global sangatlah nyata. Salah satu penyebab terjadinya pemanasan global adalah meningkatnya gas CO2. Tingginya CO2 di udara menyebabkan bertambahnya akumulasi gas-gas rumah kaca (GRK). Fenomena ini diyakini sebagai pemicu terjadinya perubahan iklim. Adanya perubahan iklim menyebabkan peningkatan frekuensi suhu ekstrim, banjir, topan, badai, kekeringan, dan naiknya permukaan air laut. Perlu adanya upaya yang dilakukan guna mengurangi emisi gas CO2, salah satunya melalui penyerapan gas CO2 oleh berbagai vegetasi tanaman hijau. Lamun merupakan satu satunya tumbuhan berbunga yang memiliki kemampuan untuk hidup terbenam di dalam perairan. Tumbuhan ini memiliki kemampuan untuk mengurangi emisi gas CO2 di lautan. Lamun mampu menyerap karbon 35 kali lebih cepat dibandingkan vegetasi hutan di darat. Sebagai penghasil biomassa yang besar, lamun dapat mengendapkan karbon (carbon sinker) di lautan. Secara alami, karbon lebih banyak tersimpan di bumi dibandingkan di atmosfer. Selain pada hewan dan tumbuhan, karbon juga dapat ditemukan pada bahan organik mati maupun sedimen seperti fosil tumbuhan dan hewan. Sebagai penyimpan karbon, padang lamun memiliki peranan penting dalam upaya mitigasi perubahan iklim. Padang lamun berfungsi sebagai penyerap dan penyimpan karbon bumi. Penelitian dilakukan di ekosistem lamun Desa Pejarakan, Bali. Data yang diambil saat kegiatan lapang meliputi parameter air laut, jenis dan kerapatan lamun, sedimen, dan wawancara mengenai persepsi serta partisipasi masyarakat akan ekosistem lamun. Setelah memperoleh data lapang, dilakukan analisis laboratorium mengenai cadangan karbon pada sedimen dengan metode loss on ignition (LOI) dan jenis butir sedimen dengan metode dry sieving. Analisis mengenai persepsi dan partisipasi masyarakat dihitung menggunakan skala likert. Hasil menunjukkan bahwa terdapat empat jenis lamun yang ditemukan pada lokasi penelitian yakni Enhalus acoroides, Thalassia hemprichii, Cymodocea rotundata, dan Halophila ovalis. Kerapatan lamun yang ada pada ekosistem lamun Desa Pejarakan tergolong rapat. Nilai kerapatan yang tinggi berpengaruh pada simpanan cadangan karbon yang ada di sedimen. Sedimen merupakan tempat penyimpanan karbon paling besar pada semua ekosistem tumbuhan. Hasil perhitungan yang telah dilakukan menunjukkan bahwa tiap stasiun pada lokasi penelitian memiliki fraksi sedimen yang berbeda. Pada Stasiun 1, fraksi sedimen yang mendominasi adalah pasir kasar dan pada Stasiun 2 dan 3 adalah pasir sedang. Jenis sedimen berpengaruh pada simpanan karbon, dimana semakin halus butir sedimen, maka semakin tinggi nilai simpanan cadangan karbonnya. Estimasi nilai cadangan karbon pada lokasi penelitian berkisar antara 10,67 – 30,37 Mg C ha-1. Estimasi serapan CO2 pada lokasi penelitian berkisar antara 896,42 – 1795,10 Mg CO2 ha-1
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