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341.
The dusky grouper is a large-bodied marine species usually associated with rocky substrates and reefs currently experiencing increasing anthropogenic pressures. Here, we critically evaluate studies conducted during the last few decades on this endangered species, focusing on its biology, ecology, behavior, stock structure and fisheries, and identify future research directions to fill current knowledge gaps. This species plays an important functional role in the rocky bottom habitats in which it lives, usually occupying the highest trophic levels and with the potential role as a keystone species in some ecosystems. It has a complex life cycle characterized by a high longevity, a slow growth rate and a monandric protogynous hermaphroditic mode of reproduction. The species also exhibits spawning aggregation behavior, which makes it more vulnerable to fishing activity. Aside from its ecological importance, this species has high commercial value for professional fishers and is also highly prized by recreational spearfishers. These biological features, associated with increasing fishing pressures throughout most of its geographical distribution, have led to Epinephelus marginatus being included since 2004 in the IUCN Red List of Threatened Species as Endangered. Despite a large amount of research being conducted on this species over the last five decades or so, using a number of different tools and techniques, key questions regarding its biology still remain unanswered. In terms of conservation and management plans designed to safeguard this endangered species, we identified the crucial need to improve fisheries landing statistics for the species and to increase the number of marine protected areas within its distribution beyond the Mediterranean Sea.  相似文献   
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Introduction: Although prostate cancer constitutes one of the most important, death-related diseases in the male population, there is still a need for identification of sensitive biomarkers that could precociously detect the disease and differentiate aggressive from indolent cancers, in order to decrease overtreatment. Proteomics research has improved understanding on mechanisms underlying tumorigenesis, cancer cells migration and invasion potential, and castration resistance. This review has focused on proteomic studies of prostate cancer published in the recent years, with a special emphasis on determination of biomarkers for cancer progression and diagnosis.

Areas covered: Shotgun and targeted-proteomic studies of prostate cancer in different matrices are reviewed, i.e., prostate tissue, prostate cell lines, blood (serum and plasma), urine, seminal plasma, and exosomes. The most important biomarkers for cancer diagnosis and aggressiveness characterization are highlighted.

Expert commentary: In general, results demonstrate alteration in cell cycle control, DNA repair, proteasomal degradation, and metabolic activity. However, these studies suffer from low reproducibility due to heterogeneity of the cancer itself, as well as to techniques utilized for protein identification/quantification. Downstream confirmatory studies in separate cohorts are warranted in order to demonstrate accuracy of these results.  相似文献   

343.
Physical methods such as electroporation have been used to improve the DNA uptake efficiency of sperm cells. This study aims to develop an efficient capillary-type electroporation method for incorporation of exogenous DNA into bovine cryopreserved sperm cells with minimal detrimental effects for later use in SMGT. Electroporation of the samples was performed in 2 different groups (with 1?μg of DNA and without DNA transfection) and under five different voltages: 500?V, 600?V, 700?V, 800?V and 900?V. Non-electroporated sperm cells (with and without DNA) were used as control. Kinetics parameters were determined using computer assisted semen analyses, whereas membrane integrity, fluidity, mitochondrial function and DNA uptake were evaluated by flow cytometry. Results revealed that all tested voltages reduced electroporated sperm motility (P?<?0.05) when compared to the control (non-electroporated cells). Mitochondrial function results showed no statistical difference among groups. Similarly, groups electroporated with lower (500?V, 600?V and 700?V) voltages showed no difference in cell membrane integrity and fluidity. Groups electroporated at higher voltages (800?V and 900?V) demonstrated negative effects in cells membrane integrity when compared to other groups and control. Also, all electroporated groups demonstrated significant higher percentages of transfected sperm cells when compared to the control group (P?<?0.05). Under the recommendation of using voltages up to 600?V, this method represents a safe and efficient alternative for electroporation of bovine spermatozoa.  相似文献   
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ABSTRACT

Proportion data from dose-response experiments are often overdispersed, characterised by a larger variance than assumed by the standard binomial model. Here, we present different models proposed in the literature that incorporate overdispersion. We also discuss how to select the best model to describe the data and present, using R software, specific code used to fit and interpret binomial, quasi-binomial, beta-binomial, and binomial-normal models, as well as to assess goodness-of-fit. We illustrate applications of these generalized linear models and generalized linear mixed models with a case study from a biological control experiment, where different isolates of Isaria fumosorosea (Hypocreales: Cordycipitaceae) were used to assess which ones presented higher resistance to UV-B radiation. We show how to test for differences between isolates and also how to statistically group isolates presenting a similar behaviour.  相似文献   
345.
In a nuclear-follower fish foraging association, the follower benefits from food uncovered or flushed out when the nuclear fish disturbs the bottom, while nuclear species generally do not seem to be benefiting. Among nuclear species, eels (anguilliform fish) are known to be one of the most represented groups. Here we investigated the frequency and time duration of foraging associations among the goldspotted eel Myrichthys ocellatus and reef fish in a subtropical marginal reef. In addition, we reviewed nuclear eel species and their followers described in the literature. From a total of 211 goldspotted eels observed, seven follower species were recorded in 19% of the samples. The average time of the following associations per species ranged from 40 to 190 s. Four species were reported for the first time as M. ocellatus followers (Bodianus rufus, B. pulchellus, Stephanolepis hispidus, and Serranus baldwini) and three of them have never been reported in the literature as eel followers (B. pulchellus, S. hispidus, and S. baldwini). The literature describes 13 eel species acting as nuclear for 66 fish species, represented mainly by groupers and sea basses. The size of the eel was not correlated with the size of its follower and neither with the number of described follower species. The nuclear role of eels is likely to be an important component of the trophic ecology of small and medium-sized macrocarnivore fish.  相似文献   
346.
We report a 38-year-old woman presenting with febrile neutropenia, acute myeloid leukemia (AML) and invasive mucormycosis. Bone marrow aspirate was characteristic of AML minimally differentiated (WHO classification 2008). Flow cytometric immunophenotyping analysis showed blasts positive for CD7, CD33, CD34, CD71, CD117, HLA-DR, MPO, and TdT, with normal karyotype (46, XX), and the absence of the FLT3-ITD and NPM1 mutations. The patient’s management included chemotherapy with cytarabine and idarubicin, and treatment with liposomal amphotericin B, deferasirox, hyperbaric oxygen therapy, and antibiotics. Nowadays, she is in complete hematological remission, and CT images of control are normal. Invasive mucormycosis is an uncommon and severe condition, which involves diagnosis and treatment challenges. Clinical features and predisposing factors should be highlighted in order to enhance the suspicion index, contributing to early diagnosis and disease control. Our aim is to report classical features of this uncommon condition and to emphasize usual management challenges.  相似文献   
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The purpose of this study was to develop and validate a multimedia software application for mobile platforms to assist in the teaching and learning process of design and construction of a skin flap. Traditional training in surgery is based on learning by doing. Initially, the use of cadavers and animal models appeared to be a valid alternative for training. However, many conflicts with these training models prompted progression to synthetic and virtual reality models. Fifty volunteer fifth- and sixth-year medical students completed a pretest and were randomly allocated into two groups of 25 students each. The control group was exposed for 5 minutes to a standard text-based print article, while the test group used multimedia software describing how to fashion a rhomboid flap. Each group then performed a cutaneous flap on a training bench model while being evaluated by three blinded BSPS (Brazilian Society of Plastic Surgery) board-certified surgeons using the OSATS (Objective Structured Assessment of Technical Skill) protocol and answered a post-test. The text-based group was then tested again using the software. The computer-assisted learning (CAL) group had superior performance as confirmed by checklist scores (p<0.002), overall global assessment (p = 0.017) and post-test results (p<0.001). All participants ranked the multimedia method as the best study tool. CAL learners exhibited better subjective and objective performance when fashioning rhomboid flaps as compared to those taught with standard print material. These findings indicate that students preferred to learn using the multimedia method.  相似文献   
350.
Since the emergence of the new severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) at the end of December 2019 in China, and with the urge of the coronavirus disease 2019 (COVID-19) pandemic, there have been huge efforts of many research teams and governmental institutions worldwide to mitigate the current scenario. Reaching more than 1,377,000 deaths in the world and still with a growing number of infections, SARS-CoV-2 remains a critical issue for global health and economic systems, with an urgency for available therapeutic options. In this scenario, as drug repurposing and discovery remains a challenge, computer-aided drug design (CADD) approaches, including machine learning (ML) techniques, can be useful tools to the design and discovery of novel potential antiviral inhibitors against SARS-CoV-2. In this work, we describe and review the current knowledge on this virus and the pandemic, the latest strategies and computational approaches applied to search for treatment options, as well as the challenges to overcome COVID-19.  相似文献   
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