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131.
1. Salinity is a strong selective force for many aquatic organisms, affecting both ecological and evolutionary processes. Most of our knowledge on the effects of salinity on rotifers in the Brachionus plicatilis species complex is based mainly on populations from waterbodies that experience broad environmental changes both seasonally and annually. We tested the hypothesis that, despite the supposedly high potential for gene flow among rotifers inhabiting neighbouring environments, constant salinity has promoted local adaptation, genetic population divergence and even cryptic speciation in B. plicatilis complex populations from three deep maar lakes of distinct salinities [1.1, 6.5 and 9.0 g L?1 total dissolved solids (TDS)] in Central Mexico. 2. To look for local adaptation, we performed common garden experiments to test the effect of different salinities on population density and intrinsic growth rate (r). Then, we evaluated the genetic divergence by sequencing the cytochrome c oxidase subunit I (COI) gene and performed reproductive trials to assess the potential gene flow among the three populations and with other closely related B. plicatilis complex species. 3. We confirmed that the rotifer populations have phenotypic plasticity in tolerance of salinity, but only rotifers from the least saline lake are adapted to low salinity. Among the populations, sequence divergence at COI was very low (just a single haplotype was found), suggesting a persistent founder effect from a relatively recent single colonisation event and a subsequent dispersal from one lake to the others, and a very restricted immigration rate. In the phylogenetic analysis, rotifers from this area of Mexico clustered in the same clade with the middle‐sized species Brachionus ibericus and B. sp. ‘Almenara’. Mexican rotifers showed successful recognition, copulation and formation of hybrids among them, but interpopulation breeding with the Spanish B. ibericus and B. sp. ‘Almenara’ was unsuccessful. 4. We conclude that the B. plicatilis complex populations from these three lakes belong to a new biological species not yet described (presently named B. sp. ‘Mexico’). To our knowledge, this is the first report of local adaptation of a natural B. plicatilis complex population living in freshwater conditions (1.1 g L?1 TDS).  相似文献   
132.
Journal of Physiology and Biochemistry - Elastin, the major protein of the extracellular matrix, is specially found in cardiovascular tissues and contributing to 30–50% of the dry weight of...  相似文献   
133.
Mycetoma is a devastating, neglected tropical disease characterised by extensive tissue involvement resulting in destruction, deformities and disabilities in the affected patients. The hand is commonly affected by mycetoma thus compromises its functionality and hinder the patient’s daily activities of living. In this communication, we report on 533 patients with hand mycetoma managed over a period of 24 years at the Mycetoma Research Centre, University of Khartoum, Khartoum, Sudan. Eumycetoma was the commonest type of mycetoma (83.3%) encountered. Males were predominately affected (69.2%) with a sex ratio of 2.2:1. The majority of the patients (84%) were young adult below the age of 40 years old at presentation. The generality of patients (86.4%) were from the Sudan mycetoma belt. Children and adolescents (28.1%), farmers (18.2%) and workers (17.4%) were more frequently affected. The majority of patients (67.4%) had disease duration of less than 5 years at presentation. The study, did not document significant history of local trauma, familial tendency, concomitant medical diseases or other predisposing cause for mycetoma in this population. Pain (23.1%) was not a disease feature in this series and 52% of patients had past surgery for mycetoma and recurrence. The right hand was affected most (60.4%), and 64% of them had small lesion at presentation. Conventional x-ray was only helpful in patients with advanced disease and the MRI accurately determined the disease extension. Cytological smears, surgical biopsies histopathological examination and grains culture were the principal diagnostic tools for causative organisms’ identification. In the present series it was difficult to determine the treatment outcome due to high patients follow up dropout.  相似文献   
134.

Background

Levels of precursor proteins of collagen I and III are increased in fibrotic pulmonary diseases. This study determined whether the expression of precursors of type I and III collagen proteins would be increased in small and large airways of COPD patients in various stages of the disease reflecting fibrogenesis.

Methods

The levels of precursor proteins of collagen I and III were studied by immunohistochemistry and quantified by image analysis in lung tissue of 16 non-smokers, 20 smokers with normal lung function, 20 smokers with stage I-II COPD and 8 ex-smokers with stage IV COPD.

Results

In large airways, the subepithelial layer which was positive for precursor proteins of collagen I and III was thicker in smokers and in stage I-II COPD compared to non-smokers. Large airways in stage IV COPD showed reduced expression of precursor protein of collagen I whereas precursor of collagen III was increased. The amount of precursor protein of collagen III was increased in small airways of smokers and stage I-II COPD but reduced in stage IV COPD.

Conclusions

Precursor proteins of collagen I and III revealed different expression profiles in large and small airways in various stages of COPD. Smoking enhanced expression of both precursors in large airways with a positive correlation with pack-years.  相似文献   
135.
Selecting near‐native conformations from the immense number of conformations generated by docking programs remains a major challenge in molecular docking. We introduce DockRank, a novel approach to scoring docked conformations based on the degree to which the interface residues of the docked conformation match a set of predicted interface residues. DockRank uses interface residues predicted by partner‐specific sequence homology‐based protein–protein interface predictor (PS‐HomPPI), which predicts the interface residues of a query protein with a specific interaction partner. We compared the performance of DockRank with several state‐of‐the‐art docking scoring functions using Success Rate (the percentage of cases that have at least one near‐native conformation among the top m conformations) and Hit Rate (the percentage of near‐native conformations that are included among the top m conformations). In cases where it is possible to obtain partner‐specific (PS) interface predictions from PS‐HomPPI, DockRank consistently outperforms both (i) ZRank and IRAD, two state‐of‐the‐art energy‐based scoring functions (improving Success Rate by up to 4‐fold); and (ii) Variants of DockRank that use predicted interface residues obtained from several protein interface predictors that do not take into account the binding partner in making interface predictions (improving success rate by up to 39‐fold). The latter result underscores the importance of using partner‐specific interface residues in scoring docked conformations. We show that DockRank, when used to re‐rank the conformations returned by ClusPro, improves upon the original ClusPro rankings in terms of both Success Rate and Hit Rate. DockRank is available as a server at http://einstein.cs.iastate.edu/DockRank/ . Proteins 2014; 82:250–267. © 2013 Wiley Periodicals, Inc.  相似文献   
136.
The luteinizing hormone receptor (LHR) is a G protein-coupled receptor involved in regulation of ovarian and testicular functions. Here we show that the receptor is present also in specific areas of the peripheral and central nervous system and may thus have a broader functional role than has been anticipated. Full-length LHR mRNA and two receptor protein species of M(r) 90,000 and 73,000, representing mature and precursor forms, respectively, were expressed in adult and developing rat nervous tissue, starting at fetal day 14.5. The receptor was capable of ligand binding because it was purified by ligand affinity chromatography, and human chorionic gonadotropin and LH were able to displace (125)I-labeled human chorionic gonadotropin binding to fetal head membranes in a dose-dependent manner. Finally, two 5'-flanking sequences ( approximately 2 and 4 kb) of the rat LHR gene were shown to direct expression of the lacZ reporter to specific areas of the peripheral and central nervous system in fetal and adult transgenic mice, especially to structures associated with sensory, memory, reproductive behavior, and autonomic functions. Importantly, the transgene activity was confined to neurons and colocalized with the cytochrome P450 side chain cleavage enzyme. Taken together, these results indicate that the neuronal LHR is a functional protein, implicating a role in neuronal development and function, possibly by means of regulating synthesis of neurosteroids.  相似文献   
137.
The aim of the present work was to study pollen-tube competition in Picea abies. Controlled crossings were performed with pollen mixtures including pairs of pollen lots with fast and slowly elongating pollen-tubes. Paternity analysis using isozyme markers was performed on the progenies in order to study whether the in vitro pollen-germination vigour corresponds to the proportion of seeds sired by the pollen donor. Paternal success was found to be unequal, 15 out of 23 crossings producing progeny that differed significantly from the hypothetical ratio of 1:1. The paternal contribution in the majority of the crossings was as expected: the pollen parent with more-vigorous in vitro germination sired more seeds than the less-vigorous pollen. In the case of two pollen mixtures, however, the seed-siring success summed over the maternal trees was the opposite to the expected value. Despite these aberrations, the results support the hypothesis that pollen-tube competition is one of the factors contributing to male fitness in P. abies. However, when all the other factors affecting pollination and seed set under natural conditions are taken into account, it is clear that the seed-siring success of a particular paternal genotype cannot be predicted reliably by measuring only the in vitro pollen vigour. Received: 2 July 2001 / Accepted: 7 August 2001  相似文献   
138.
A severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) led novel coronavirus disease (COVID-19) outbreak spread through China has become the biggest global public health challenge today. The virus upon several mutations has led to the resurgence of more infectious and lethal variants infecting over 298 million people with more than 5.46 million deaths worldwide by the end of December, 2021. Though vaccines are available, various preventive measures particularly a high body immunity is still extremely important which determines the likelihood of disease severity and subsequent recovery in the current and future pandemics. This review acknowledges the potentiality of miraculous Moringa oleifera Lam. against recently evolved novel coronavirus and accompanying health complications. Moringa a well-proven super-food, densely packed with an abundant quantity of 92 minerals, several vitamins, 46 antioxidants, and numerous bioactive compounds, thus own a massive therapeutic potential for healing all levels of nutritional deficiencies and poor immunities and cure above 300 diseases. Moringa acts as anti-asthmatic, anti-cancerous, anti-diabetic, anti-inflammatory, hypotensive, hepatic, renal and cardio-protective, and anti-viral in nature. Thus it may reduce the severity of COVID-19 infections and associated serious medical emergencies. In addition, self-isolation at home or the workplace has put people at increased risk of physical and mental sicknesses, which could be simply addressed by integrating this wonderful plant into everyday diet. Furthermore, the immune-modulatory properties and viral inhibiting nature of moringa contribute to reduced risk of COVID-19 infection and quicker recovery from its symptoms. As per the existing pieces of literature, it is a great time to harness the esteemed moringa for safeguarding people from the terrible ongoing COVID-19 situation and other future pandemics.  相似文献   
139.
140.
A palaeoecological analysis of the Penarth Group (='Rhaetic') of southern England and Wales is undertaken in terms of a species-richness comparison with the Zlambach and Kössen Beds of the Austrian Alps. The three groups studied, bivalves, foraminifers and ostracodes, comprise the most important invertebrate faunas occurring in the deposits cited. All show significant diversity from the Alps into northwest Europe. Coupled with the disappearance of stenohaline elements including ammonites, and taking into account other facies information, the evidence suggests a transgression of a shallow epicontinental sea in northwest Europe at the end of the Triassic. The salinity of this sea (˜25–30%□) was appreciably below that of the Tethyan ocean.  相似文献   
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