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Mcgowan Boje opublikował 1 rok, 8 miesięcy temu
Malic enzymes participate in key metabolic processes, the MaeB-like malic enzymes carry a catalytic inactive phosphotransacetylase domain whose function remains elusive. Here we show that acetyl-CoA directly binds and inhibits MaeB-like enzymes with a saturable profile under physiological relevant acetyl-CoA concentrations. A MaeB-like enzyme from the nitrogen-fixing bacterium Azospirillum brasilense, namely AbMaeB1, binds both acetyl-CoA and unesterified CoASH in a way that inhibition of AbMaeB1 by acetyl-CoA is relieved by increasing CoASH concentrations. Hence, AbMaeB1 senses the acetyl-CoA/CoASH ratio. We revisited E. coli MaeB regulation to determine the inhibitory constant for acetyl-CoA. Our data support that the phosphotransacetylase domain of MaeB-like enzymes senses acetyl-CoA to dictate the fate of carbon distribution at the phosphoenol-pyruvate / pyruvate / oxaloacetate metabolic node.Background Asthma prevalence decreases post-puberty in males. Testosterone inhibits airway smooth muscle contraction and attenuates type 2 inflammation. Objective To investigate the relationship between serum testosterone and current asthma prevalence and lung function in a nationally-representative dataset. Methods Serum testosterone and self-reported physician-diagnosed current asthma were obtained from 7,584 participants ages 6-80 years from the cross-sectional 2011-2012 National Health and Nutrition Examination Survey (NHANES). We used logistic regression to test associations between testosterone and current asthma, adjusting for demographics and stratifying by sex and age; linear regression to evaluate correlations between testosterone and lung function among asthmatic patients; and interaction terms to test for effect modification by blood eosinophils and FeNO. Results Serum testosterone inversely associated with odds of current asthma in both men and women but this association was nonlinear. Similar protective effect sizes were observed for both sexes after log2-transformation of serum testosterone. For every 1-unit increase in log2 testosterone, the odds of current asthma decreased by 11% in men and 10% in women, although the association was statistically significant in women only among those ≥12 years old after multiple imputation. Serum testosterone did not associate with current asthma prevalence among those less then 12 years old. Testosterone associated with increases in FEV1 in asthmatic participants of both sexes. Neither blood eosinophils nor FeNO modified the association between testosterone and current asthma. Conclusion Serum testosterone inversely associates with current asthma prevalence regardless of sex and correlates with better lung function in a nationally-representative database. Androgen therapy for asthma should be further investigated.Background New diagnostic criteria consider Alzheimer’s disease (AD) as a clinico-biological entity identifiable in vivo on the presence of specific patterns of CSF biomarkers. Objective Here we used transcranial magnetic stimulation to investigate the mechanisms of cortical plasticity and sensory-motor integration in patients with hippocampal-type memory impairment admitted for the first time in the memory clinic stratified according to CSF biomarkers profile. Methods Seventy-three patients were recruited and divided in three groups according to the new diagnostic criteria 1) Mild Cognitive Impaired (MCI) patients (n = 21); Prodromal AD (PROAD) patients (n = 24); AD with manifest dementia (ADD) patients (n = 28). At time of recruitment all patients underwent CSF sampling for diagnostic purposes. Repetitive and paired-pulse transcranial magnetic stimulation protocols were performed to investigate LTP-like and LTD-like cortical plasticity, short intracortical inhibition (SICI) and short afferent inhibition (SAI). Patients were the followed up during three years to monitor the clinical progression or the conversion to dementia. Results MCI patients showed a moderate but significant impairment of LTP-like cortical plasticity, while ADD and PROAD groups showed a more severe loss of LTP-like cortical plasticity. No differences were observed for LTD-like cortical plasticity, SICI and SAI protocols. Kaplan-Meyer analyses showed that PROAD and MCI patients converting to dementia had weaker LTP-like plasticity at time of first evaluation. Conclusion LTP-like cortical plasticity could be a novel biomarker to predict the clinical progression to dementia in patients with memory impairment at prodromal stages of AD identifiable with the new diagnostic criteria based on CSF biomarkers.RT-qPCR requires an adequate choice of stably expressed reference genes for accurate normalization of mRNA expression. However, testing a panel of reference genes is often time-consuming and expensive. In this work, we aimed to develop a set of multiplex real-time PCR assays for RT-qPCR analysis of commonly used housekeeping genes in laboratory rats. Using Hydrolysis probe (TaqMan®) technology, we have designed and optimized three triplex qPCR assays (Actb + Gapdh + B2m; Rpl13a + Sdha + Ppia; Hprt1+Pgk1+Ywhaz) demonstrating optimal PCR amplification efficiencies (from 94.7 to 100.5%) and repeatability. Novel assays allow expression analysis of 9 reference genes in 3 reactions making possible a more time-efficient choice of reference genes in RT-qPCR experiments in Wistar rats in comparison with widespread singleplex assays.Increasingly globalized and complex food supply chains contribute to a growing problem of meat fraud. Meat adulteration with pork is especially exceptionable to the global population for health concern and religious faith reasons. To prevent unfair competition and protect consumer rights, an efficient and rapid assay to identify the species of meat products is crucial. In this study, a real-time loop-mediated isothermal amplification (real-time LAMP) assay was developed for the detection of a porcine gene in meat products. The designed primers were highly selective for the porcine gene. The amplification showed no cross-reactivity with 11 other meats. The established method required 20 min with an initial amplification curve of approximately 10 min and demonstrated a detection limit of 1.76 pg/μL porcine DNA, which is 1000 times more sensitive than PCR. This study is the first attempt at detecting porcine-derived ingredients using a real-time LAMP assay in commercial products. This method meets specificity, rapidness, robustness, and sensitivity criteria; its practical application will greatly aid in battling adulteration in the food industry.Mirror self-recognition (MSR) is considered a crucial step in the emergence of self-cognition. The MSR paradigm has become a standard method for evaluating self-cognition in several species. For example, Eurasian magpies and Indian house crows have passed the mark test for self-cognition, whereas efforts to find MSR in other corvid species have failed. However, no literature has conducted MSR tests on azure-winged magpies, a species of corvids. Therefore, the current research aimed to investigate the MSR behaviours of azure-winged magpies upon looking into a mirror for the first time. The study included four tests (1) mirror preference and standardised mirror exploration, (2) single vertical mirror test, (3) mark test and (4) mirror-triggered search test. The azure-winged magpies displayed immense curiosity towards the mirror and their images in the mirror in Test 1&2. In the subsequent mark tests, they failed to recognise themselves in the mirror and regarded their images as conspecifics. Behaviour analysis showed no significant difference between marked and unmarked behaviours. Finally they seemed to infer the presence of bait from the image in the mirror, but were found to fail to understand that the location of the bait in the mirror was the same as that in the real world. For a better insight into the MSR behaviour of azure-winged magpies, research studies involving prolonged mirror exposure and training are recommended.The treatment against visceral leishmaniasis (VL) presents problems, mainly related to the toxicity and/or high cost of the drugs. In this context, a rapid and precise diagnosis of the disease should be performed, mainly to treat patients as soon as possible, aiming to reduce the treatment time and the toxicity of the therapeutics. In the present study, the diagnostic role of an amastigote-specific Leishmania protein was evaluated in the canine and human VL. Results showed that the recombinant protein (called rLiHyJ) and one specific B cell epitope (called PeptJ) predicted from protein sequence presented high sensitivity and specificity values to diagnose canine and human disease, showing also a low reactivity against cross-reactive samples. The rA2 protein and a parasite antigenic extract showed variable sensitivity and/or specificity values in the ELISA experiments. A prognostic evaluation of protein and peptide in the human VL indicated that specific IgG antibodies significantly decreased after treatment, when compared to be values obtained before therapy. The in vitro immunogenicity using rLiHyJ in peripheral blood mononuclear cell (PBMC) cultures collected of such patients and healthy subjects suggested that the protein induced lymphoproliferation and high IFN-γ production in the stimulated cells. In conclusion, although preliminary, results suggest that rLiHyJ and PeptJ could present distinct biotechnological applications in the canine and human VL.Clinical symptoms of B vitamin deficiency are rarely observed in ruminants because these vitamins are synthesized by the rumen microbiota. However, over the last decades, numerous reports of beneficial effects on production and metabolic efficiency of dairy cows have been published supporting that, under some conditions, B vitamin subclinical deficiency is present in these animals. Due to their roles as coenzymes or cofactors in major metabolic pathways, an adequate supply in B vitamins is critical to optimize metabolic efficiency. Nowadays, taking into account the growing interest for the Smart Farming concept, fulfilling ruminant requirements for B vitamins according to their physiological stage under different feeding management cannot be neglected. In dairy cows, B vitamin supply is greatly dependent of the activity of the ruminal microbiota. Indeed, the amount of vitamins reaching the small intestine is dependent of the utilization of the vitamins provided by the diet and their synthesis by the microorganisms present in the rumen. The two major challenges faced to determine B vitamin status of ruminants are the difficulty to estimate B vitamin supply due to the lack of knowledge on factors driving the fate of B vitamins in the digestive tract, especially in the rumen, and the choice and thresholds of biomarkers reflecting adequately the animal status. The present paper aims to present the actual state of knowledge on the methodological approaches used to estimate B vitamin supply and status of ruminant and to point out future research orientations.Parkinson’s disease (PD) is a progressive neurodegenerative disease, which shows distinct manifestations such as significant loss of dopaminergic neurons in the substantia nigra (SN). Gene expression was analyzed in the SN of mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), wherein downregulation of dopaminergic neurons occurred to examine the possible causes leading to the loss of dopaminergic neurons. In addition, a serine/cysteine protease inhibitor (Serping1) was studied as one of the genes that were prominently upregulated in mice chronically intoxicated with MPTP. Western blot analysis showed that, concomitant to the downregulation of dopaminergic cells, there was a substantial increase in Serping1 expression within the SN of the MPTP-induced PD mouse model. The SH-SY5Y cells were transfected with Serping1 short interfering RNA (siRNA) to evaluate the correlation between the expression of Serping1 and the loss of dopaminergic cells. Serping1 depletion elicited the upregulation of dopaminergic cells.


