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101.
Monoclonal antibodies reactive with deoxynivalenol were generated following the immunization of mice with a deoxynivalenol‐mouse serum albumin conjugate. One of the anti‐deoxynivalenol monoclonal antibodies, designated C6–1, exhibited cross‐reactivity with 3‐acetyldeoxynivalenol and 15‐acetyldeoxynivalenol but not with nivalenol, T‐2 tetraol or scirpentriol. An indirect competitive ELISA based on this monoclonal antibody gave 50% inhibition values of 0–6 μg ml‐1 for deoxynivalenol, 0–2 μg ml‐1 for 15‐acetyldeoxynivalenol and 10 μg ml‐1 for 3‐acetyldeoxynivalenol.  相似文献   
102.
Despite magnesium (Mg2+) representing the second most abundant cation in the cell, its role in cellular physiology and pathology is far from being elucidated. Mg2+ homeostasis is regulated by Mg2+ transporters including Mitochondrial RNA Splicing Protein 2 (MRS2), Transient Receptor Potential Cation Channel Subfamily M, Member 6/7 (TRPM6/7), Magnesium Transporter 1 (MAGT1), Solute Carrier Family 41 Member 1 (SCL41A1), and Cyclin and CBS Domain Divalent Metal Cation Transport Mediator (CNNM) proteins. Recent data show that Mg2+ transporters may regulate several cancer cell hallmarks. In this review, we describe the expression of Mg2+ transporters in digestive cancers, the most common and deadliest malignancies worldwide. Moreover, Mg2+ transporters’ expression, correlation and impact on patient overall and disease-free survival is analyzed using Genotype Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) datasets. Finally, we discuss the role of these Mg2+ transporters in the regulation of cancer cell fates and oncogenic signaling pathways.  相似文献   
103.
The objective of the present review is to provide an overview of existing research that has reported on the association between posttraumatic stress disorder (PTSD) and ischemic heart disease. Specific focus is given to the incidence of PTSD following myocardial infarction (MI). A systematic review using Preferred Reporting Items for Systematic reviews and Meta‐Analysis (PRISMA) guidelines was performed by searching four bibliographic databases: PubMed, PsychINFO, ScienceDirect, and ProQuest Dissertations and Theses. A total of 39 articles were included in this literature review. The results of these studies suggest that the occurrence of an acute cardiac event is likely to contribute to the development of PTSD. Not only is this type of psychiatric disorder associated with significant suffering and impaired quality of life, but it is also a predictor of an increased risk of recurrent adverse cardiovascular events and mortality. Screening, assessment, and treatment of PTSD and posttraumatic stress symptoms following a major cardiac event are critical for offsetting potential deleterious psychological and physical consequences.  相似文献   
104.
BackgroundThe principal triggers for intervention in the setting of pediatric blunt solid organ injury (BSOI) are declining hemoglobin values and hemodynamic instability. The clinical management of BSOI is, however, complex. We therefore hypothesized that state-of-art machine learning (computer-based) algorithms could be leveraged to discover new combinations of clinical variables that might herald the need for an escalation in care. We developed algorithms to predict the need for massive transfusion (MT), failure of non-operative management (NOM), mortality, and successful non-operative management without intervention, all within 4 hours of emergency department (ED) presentation.MethodsChildren (≤ 18 years) who sustained a BSOI (liver, spleen, and/or kidney) between 2009 and 2018 were identified in the trauma registry at a pediatric level 1 trauma center. Deep learning models were developed using clinical values [vital signs, shock index-pediatric adjusted (SIPA), organ injured, and blood products received], laboratory results [hemoglobin, base deficit, INR, lactate, thromboelastography (TEG)], and imaging findings [focused assessment with sonography in trauma (FAST) and grade of injury on computed tomography scan] from pre-hospital to ED settings for prediction of MT, failure of NOM, mortality, and successful NOM without intervention. Sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) were used to evaluate each model's performance.ResultsA total of 477 patients were included, of which 5.7% required MT (27/477), 7.2% failed NOM (34/477), 4.4% died (21/477), and 89.1% had successful NOM (425/477). The accuracy of the models in the validation set was as follows: MT (90.5%), failure of NOM (83.8%), mortality (91.9%), and successful NOM without intervention (90.3%). Serial vital signs, the grade of organ injury, hemoglobin, and positive FAST had low correlations with outcomes.ConclusionDeep learning-based models using a combination of clinical, laboratory and radiographic features can predict the need for emergent intervention (MT, angioembolization, or operative management) and mortality with high accuracy and sensitivity using data available in the first 4 hours of admission. Further research is needed to externally validate and determine the feasibility of prospectively applying this framework to improve care and outcomes.Level of EvidenceIIIStudy TypeRetrospective comparative study (Prognosis/Care Management).  相似文献   
105.

Since the emergence of the COVID-19 pandemic, there has been an increasing body of research focused on the effects that measures like stay-at-home orders and social distancing are having on other aspects of health, including mental health and sexual health. Currently, there are limited extant data on the effects of the pandemic on sexual and gender minorities. Between April 15, 2020, and May 15, 2020, we invited participants in an ongoing U.S. national cohort study (Together 5000) to complete a cross-sectional online survey about the pandemic, and its effects on mental and sexual health and well-being (n?=?3991). Nearly all (97.7%) were living in an area where they were told they should only leave their homes for essentials. Most (70.1%) reported reducing their number of sex partners as a result of the pandemic. Among the 789 participants prescribed HIV pre-exposure prophylaxis (PrEP), 29.9% said they stopped taking their PrEP entirely, and 14.2% started selectively skipping doses. For those who had been taking PrEP, discontinuing PrEP was associated with having no new sex partners (β?=?0.90, 95% CI 0.40–1.40). Among the 152 HIV-positive participants, 30.9% said they were unable to maintain an HIV-related medical appointment because of the pandemic and 13.8% said they had been unable to retrieve HIV medications. Additionally, 35.3% of participants were experiencing moderate to severe anxiety because of the pandemic and 36.7% reported symptoms of depression. In a multivariable logistic regression, reporting a new sex partner in the prior 30 days was significantly associated with being aged 30 or older (vs. not, AOR?=?1.21), being Black (AOR?=?1.79) or Latinx (AOR?=?1.40, vs. white), and being unsure if they had been in close contact with someone diagnosed with COVID-19 (AOR?=?1.32, vs. no contact). It was unassociated with COVID-19-induced anxiety, depression, or knowing someone hospitalized with COVID-19. The pandemic has caused disruptions in sexual behavior (partner reduction) as well as difficulties navigating PrEP and HIV care continua. Findings will guide more comprehensive public health responses to optimize HIV prevention and treatment in the era of COVID-19.

  相似文献   
106.
Intrathoracic Kaposi's sarcoma (KS) in AIDS is remarkable for its frequency and severity. It is responsible for 10% of "pneumonias" and almost 50% of pleurisies observed in these patients. The time elapsed between the discovery of the lesion and the patient's death does not exceed a few months on average. The initial manifestations of pulmonary KS are usually discreet and consist of cough and/or dyspnoea in patients with KS of the skin and mucosae. Fever is lacking or moderate. The most suggestive radiological findings are dense, nodular, tumour-like opacities and bilateral linear and/or micronodular opacities around the bronchi and vessels. The diagnosis rests on bronchial fibroscopy which shows red, non friable lesions which, to a trained endoscopist, are very characteristic. When these lesions are absent, thoracotomy may be necessary for diagnostic purposes. Treatment essentially consists of chemotherapy; zidovudine therapy and prophylaxis of pneumocystosis are indicated if the circulating CD 4 cell count falls below 200/mm3. When its symptoms are predominant, pleural KS is typically progressive, with normal or slightly elevated temperature, associated parenchymal lesions that are clearly visible on CT scans and copious, bilateral, blood-stained serous or chylous pleural fluid. When these signs are absent throacoscopy or thoracotomy may be necessary. Future advances in this field will be due not only to improvements in chemotherapy but also to a better understanding of the physiopathology of intrathoracic Kaposi's sarcoma.  相似文献   
107.
Calcium (Ca) supplements have positive effects in growing children, reduce bone loss in late-postmenopausal women with a low calcium diet and, in association with vitamin D3 supplements, may reduce non-vertebral fracture rates in elderly women. However, for many formulated pharmaceutical products their relative beneficial effects have not been conclusively established. We have compared the acute (6 h) metabolic responses following oral administration of two preparations of calcium gluconolactate and carbonate (CG and CG), tricalcium phosphate (TCP) and calcium citrate (CC), given on separate occasions in each of 10 healthy young male volunteers. The subjects fasted overnight for 12 h and continued to fast during the experimental procedure. A 1000 mg dose of each Ca salt was ingested at weekly intervals. Blood was drawn after 30, 60, 90, 120, 180, 240, 300 and 360 min for measurement of serum Ca, phosphorus (P), parathyroid hormone (PTH) and whole plasma calcitonin (iCT). All Ca supplements induced significant (+6.4% to +8.1%;p<0.01) increases in Ca and significant suppression of PTH (–37.4% to –57.4%;p<0.01). Comparison of response curves revealed significantly (p<0.01) more marked Ca increase and PTH suppression with CC than with the other three Ca salts. CG' and CC induced marginal decreases in serum P and the overall curve of P variations was different for TCP compared with CG, CG and CC. No significant variation of iCT was recorded during the test. We conclude that all four Ca supplements seem to be absorbed to some extent since they induce significant biochemical variations that may lead to a reduction in bone turnover and that CC induces a significantly larger increase in serum Ca and a significantly greater suppression of serum PTH.  相似文献   
108.
We have obtained a clone of the Pichia pastoris HIS4 gene and have determined its nucleotide sequence. Based upon its deduced amino-acid sequence, the product of the P. pastoris HIS4 gene has the same structural organization as the Saccharomyces cerevisiae His4 protein and appears to encode a trifunctional enzyme catalyzing the second (phosphoribosyl-ATP pyrophosphohydrolase), third (phosphoribosyl-AMP cyclohydrolase), and tenth (histidinol dehydrogenase) steps in histidine biosynthesis. The chromosomal copy of the HIS4 gene was disrupted by homologous recombination, creating the strain SGY58. The his4 deletion mutation in this strain lacks the entire coding region of this gene and has a reversion rate that is undetectable. A set of complementary plasmids that carry the HIS4 gene was also developed. Among these are nine E. coli-P. pastoris shuttle vectors that transform the His4 deletion mutant at high efficiency and an integration vector for creating site-specific alterations of the P. pastoris genome.  相似文献   
109.
Morgan  Denis J.  Xu  Cao Ling 《Pharmaceutical research》1994,11(12):1820-1824
It has been suggested that albumin reduces quinidine capillary permeability (PS) in the single-pass perfused heart preparation by reducing paracellular transport of quinidine ions. Using this preparation, we examined the effect of albumin (0.1 per cent) on quinidine PS at perfusate pHs of 7.1 and 7.9 during uptake of quinidine (19 µM) and also during washout of the drug using a randomized design. Quinidine PS was approximately 16 ml/min/g heart at pH 7.9 and was not altered by the presence of albumin in perfusate. At pH 7.1, in the absence of albumin, quinidine PS was also 16 ml/min/g, but in the presence of albumin (0.1 per cent) PS was reduced significantly to approximately 5 ml/min/g (P < 0.001). In the absence of albumin PS was the same at pH 7.1 and 7.9 in spite of a greater degree of ionisation of quinidine at pH 7.1. This suggests that there is significant uptake of ionised quinidine at pH 7.1. The greater effect of albumin on PS at pH 7.1 supports the hypothesis that albumin reduces paracellular transport of quinidine ions.  相似文献   
110.
The general objective of our work was to propose new reference material for chemical toxicity testing and new sentinel organisms for environmental quality survey programs (freshwater or soils). We also wanted to provide basic toxicological data on the environmental effects of uranium. Thus, we conducted a comparative study to establish the acute toxicity and toxicokinetics of lead (Pb) and uranium (U) to the bivalve mollusc Corbicula fluminea and the terrestrial annelid Eisenia fetida andrei and to compare these findings with those of the well-known teleost fish Brachydanio rerio. We then measured the concentration of these metals in various tissues of the clam and the worm after two periods of exposure (4 and 11 days) to identify the affinities of these tissues for Pb and U. Our results have shown that Pb and U are very toxic to Eisenia and relatively nontoxic to Corbicula. By comparison, Pb was relatively nontoxic and U appeared to be very toxic to the fish. The toxicokinetic studies indicated that the three species are able to accumulate Pb and U, the rate and level of accumulation depending both on the species and the metal. We also found that fish and clams depurate the two metals. Data collected for the worm were conflicting: Pb was not depurated whereas tissue concentrations of U declined after the eighth day of exposure. Our study has also shown that the tissue distribution of Pb in the mollusc and in the earthworm differs significantly from that of U, both after 4 and 11 days exposure. In conclusion, these three species showed potential as bioindicators of environmental contamination by metals. Indeed, they could be used in conjunction to test different compartments of an ecosystem: worms for soils, fish for the water column, and clams for the water/sediment interface. Received: 30 October 1996/Accepted: 1 September 1998  相似文献   
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