1,273 research outputs found

    Angiotensin II is Required to Induce Exaggerated Salt Sensitivity in Dahl Rats Exposed to Maternal Separation

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    We previously reported that maternal separation, rat model of early life stress, enhances pressor responses to acute and chronic stressors. The aims of this study were to determine whether Dahl salt-sensitive (DS) rats subjected to maternal separation (MatSep-DS) as compared to normally reared DS (Ctl-DS) rats show exaggerated blood pressure responses to acute behavioral stressors, such as restraint stress or air jet stress (AJS), or, hypertensive stimuli including chronic high-salt diet (4% NaCl) and angiotensin II (AngII) infusion (200 ng/Kg/min) during 1 week. MatSep was performed in male DS rats for 3 h/day from postnatal days 2-14. At 8 weeks of age, rats were implanted with telemetry transmitters and allowed to recover. Mean arterial pressure (MAP) was not different between MatSep-DS and Ctl-DS rats at baseline (120 ± 2 mmHg vs. 118 ± 1 mmHg, n = 4-8). Blood pressure responses during AJS and restraint stress were not different between MatSep-DS and Ctl-DS at 3 min. However, blood pressure recovery from AJS was significantly impaired in MatSep-DS rats compared to Ctl-DS rats (P \u3c 0.05). 3-h stress-induced similar responses in MatSep and Ctl-DS rats. Chronic blood pressure responses to AngII infusion in rats fed a high-salt diet displayed enhanced MAP in MatSep-DS when compared with Ctl-DS rats (167 ± 5 mmHg vs. 152 ± 2 mmHg, pinteraction \u3c0.05). However, MAP increased similarly in both groups in response to AngII infusion or high-salt diet separately. Renal parameters such as proteinuria, urine flow rate, and urine electrolytes were not different between groups in response to each treatment. In summary, salt sensitivity induces exaggerated blood pressor responses only in presence of AngII due to early life stress

    Impact of cropping systems on soil properties, nutrient availability and their carbon sequestration potential in Shiwalik hills of Himachal Pradesh

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    The impact of cropping systems on soil properties, nutrient availability and their carbon sequestration potential was studied during the years 2014 and 2015 in Shiwalik hills of Himachal Pradesh. The four commonly occurring cropping systems namely vegetable, fruit, cereal crop and agroforestry were selected. Uncultivated land in the region was considered as control. In total, there were five treatments which were replicated six times under randomized block design. The study indicated that the cropping systems in the Shiwalik hills varied significantly (P=0.05) with respect to their impact on soil properties, nutrient availability and carbon sequestration potential. The pH and EC was in the range of 6.04 to 6.90 and 0.094 to 0.138 dSm-1, respectively and were normal in range. Organic carbon and bulk density in surface soils ranged from 8.06 to 9.70 g kg-1 and 1.19 to 1.34 Mg m-3, respectively. The available NPK was highest (267.21, 19.99, 172.42 kg ha-1) under vegetable based cropping system as compared to other systems. Carbon density in surface soil ranged from 11.33 to 15.39 Mg C ha-1 and total carbon sequestered upto 30cm soil depth ranged from 601.96 to 12646.29 Gg. The study indicated that in Shiwalik hills of Himachal Pradesh, the commonly occurring cropping systems did not influence the soil properties and nutrient availability adversely. Agroforestry based cropping system is having highest potential of sequestering soil carbon in Shiwalik hills. Therefore to adapt to changing climatic situation and to mitigate its effect in the region, agroforestry based cropping system need to be encouraged

    Effects of an inactivated vaccine for bovine mycoplasmosis on calves naturally affected with Mycoplasma bovis

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    Three autogenous vaccine trials were carried out on farms where Mycoplasma bovis had been identified as a major pathogen. The first trial was carried on a veal farm in the Lombardia region of northern Italy. Vaccine, prepared by saponising an M bovis strain taken from the farm some months before, was given as single inoculation to 24 calves on arrival while 19 were left unvaccinated. Six months later calves were sent to the abattoir where lungs were examined for gross pathological lesions. The mean weight of the vaccinated group was higher though not significantly so and mean lesion scores were similar; however the percentage of vaccinated calves with severe lung lesions and pleuritis was lower than in the non vaccinates. A second trial was carried out in northern England on a farm where monthly batches of male calves from a nearby dairy herd were reared under a feedlot system. One group of 27 calves were vaccinated with a saponised strain of M bovis isolated from the lungs of a pneumonic calf on the farm prior to the start of the trial. A second batch of 25 calves was left unvaccinated. The groups of calves were monitored for nine months prior to slaughter and records kept of antibiotic usage and mortality. The mortality rates in the vaccinated calves were about 15% compared to 28% in unvaccinated calves; however there was no difference in the number of times calves were treated for respiratory disease. A third batch of calves, treated with oxytetracycline on arrival because a number were already showing respiratory signs, had a lower mortality rate and fewer subsequent treatments. A third trial was carried out on a milk veal unit in the Veneto region of Italy. A group of 19 calves were vaccinated on arrival with a saponised isolate taken earlier from the farm; a similar number of calves of the same batch were left unvaccinated. After 6 months animals were routinely processed at the abattoir and lungs inspected. Results showed that vaccinated calves had higher mean body weights and although similar mean lung scores there was a smaller percentage of vaccinated calves with severe lung lesions and pleuritis

    Developmental Origins of Cardiovascular Disease: Impact of Early Life Stress in Humans and Rodents

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    The Developmental Origins of Health and Disease (DOHaD) hypothesizes that environmental insults during childhood programs the individual to develop chronic disease in adulthood. Emerging epidemiological data strongly supports that early life stress (ELS) given by the exposure to adverse childhood experiences is regarded as an independent risk factor capable of predicting future risk of cardiovascular disease. Experimental animal models utilizing chronic behavioral stress during postnatal life, specifically maternal separation (MatSep) provides a suitable tool to elucidate molecular mechanisms by which ELS increases the risk to develop cardiovascular disease, including hypertension. The purpose of this review is to highlight current epidemiological studies linking ELS to the development of cardiovascular disease and to discuss the potential molecular mechanisms identified from animal studies. Overall, this review reveals the need for future investigations to further clarify the molecular mechanisms of ELS in order to develop more personalized therapeutics to mitigate the long-term consequences of chronic behavioral stress including cardiovascular and heart disease in adulthood

    Eigenvector Centrality Distribution for Characterization of Protein Allosteric Pathways

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    Determining the principal energy pathways for allosteric communication in biomolecules, that occur as a result of thermal motion, remains challenging due to the intrinsic complexity of the systems involved. Graph theory provides an approach for making sense of such complexity, where allosteric proteins can be represented as networks of amino acids. In this work, we establish the eigenvector centrality metric in terms of the mutual information, as a mean of elucidating the allosteric mechanism that regulates the enzymatic activity of proteins. Moreover, we propose a strategy to characterize the range of the physical interactions that underlie the allosteric process. In particular, the well known enzyme, imidazol glycerol phosphate synthase (IGPS), is utilized to test the proposed methodology. The eigenvector centrality measurement successfully describes the allosteric pathways of IGPS, and allows to pinpoint key amino acids in terms of their relevance in the momentum transfer process. The resulting insight can be utilized for refining the control of IGPS activity, widening the scope for its engineering. Furthermore, we propose a new centrality metric quantifying the relevance of the surroundings of each residue. In addition, the proposed technique is validated against experimental solution NMR measurements yielding fully consistent results. Overall, the methodologies proposed in the present work constitute a powerful and cost effective strategy to gain insight on the allosteric mechanism of proteins

    Sex-Specific Alterations in NOS Regulation of Vascular Function in Aorta and Mesenteric Arteries from Spontaneously Hypertensive Rats Compared to Wistar Kyoto Rats

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    The present study tested the hypothesis that spontaneously hypertensive rats (SHR) have impaired nitric oxide synthase (NOS)-mediated regulation of vascular function versus Wistar-Kyoto rats (WKY). Aorta and small mesenteric arteries were studied from male and female SHR (M SHR and F SHR) and WKY (M WKY and F WKY). Phenylephrine (PE)-induced vasoconstriction was greater in aorta of M SHR versus all others (P \u3c 0.05); there were neither sex nor strain differences in PE contraction in mesenteric arteries. The NOS inhibitor l-Nitro-Arginine Methyl Ester (l-NAME) increased PE-induced vasoconstriction in all rats, although the increase was the least in male SHR (P \u3c 0.05), revealing a blunted vasoconstrictor buffering capacity of NOS. l-NAME increased sensitivity to PE-induced constriction only in mesenteric arteries of SHR, although, the maximal percent increase in contraction was comparable among groups. ACh-induced relaxation was also less in aorta from M SHR versus all others (P \u3c 0.05). ACh relaxation was comparable among groups in mesenteric arteries, although SHR exhibited a greater NOS component to ACh-induced relaxation than WKY. To gain mechanistic insight into sex and strain differences in vascular function, NOS activity and NOS3 protein expression were measured. Aortic NOS activity was comparable between groups and M SHR had greater NOS3 expression than M WKY. In contrast, although vascular function was largely maintained in mesenteric arteries of SHR, NOS activity was less in SHR versus WKY. In conclusion, M SHR exhibit a decrease in NOS regulation of vascular function compared to F SHR and WKY, although this is not mediated by decreases in NOS activity and/or expression

    A family of virtual contraction based controllers for tracking of flexible-joints port-Hamiltonian robots:Theory and experiments

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    In this work, we present a constructive method to design a family of virtual contraction based controllers that solve the standard trajectory tracking problem of flexible-joint robots in the port-Hamiltonian framework. The proposed design method, called virtual contraction based control, combines the concepts of virtual control systems and contraction analysis. It is shown that under potential energy matching conditions, the closed-loop virtual system is contractive and exponential convergence to a predefined trajectory is guaranteed. Moreover, the closed-loop virtual system exhibits properties such as structure preservation, differential passivity, and the existence of (incrementally) passive maps. The method is later applied to a planar RR robot, and two nonlinear tracking control schemes in the developed controllers family are designed using different contraction analysis approaches. Experiments confirm the theoretical results for each controller

    Optimisation of a one-step PCR assay for the diagnosis of Flavescence doreerelated phytoplasmas in field-grown grapevines and vector populations

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    Field-infected grapevines and natural populations of Scaphoideus titanus have been analysed to detect group V phytoplasmas associated with flavescence doree in northwestern Italy using nested PCR. A first amplification driven by universal ribosomal primers R16SF2/R2 was followed by a second round assisted by R16(V)F1/R1 primers and subsequent RFLP analysis. To optimize the test, nested PCRs were compared with direct amplification assisted by the group V-specific fAY/rEY primer pair, directed towards other ribosomal sequences. In nested and direct PCRs, respectively, DNAs from 71 and 57 out of 96 grapevines (i.e. 73.9 and 59.3 %) and 51 and 50 out of 108 insects (i.e. 47.2 and 46.3 %) reacted positively. Although it was not possible to determine the subgroup of the phytoplasmas after fAY/rEY amplification, these primers could be used successfully in mass screening of plant material and insect populations. They could detect, in single-step amplification, the phytoplasmas in 80 and 98 % of the plant and insect samples, respectively, that were already indexed as positive using nested PCR. This strongly reduced the number of samples requiring the nested approach, with beneficial effects on costs, labour and risks of the analysis.

    Le motivazioni del cospirazionismo

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    Che cosa comporta abbracciare una teoria cospirazionista? Perché il cospirazionista, indipendentemente dal livello di istruzione e dalla professione, cerca di difenderla e diffonderla addirittura, nonostante palesi contraddizioni talvolta molto fantasiose? Secondo gli autori, l’unico modo per dare una risposta soddisfacente alla comprensione del fenomeno del cospirazionismo - un fenomeno sociale che ha raggiunto una diffusione preoccupante con serie implicazioni a livello psicologico, culturale e politico – è riuscire a comprendere le ragioni del suo fascino. Gli autori illustrano una possibile ‘ricetta perfetta’ perché si inneschi e si autoalimenti la mentalità cospirazionista. Dalla revisione della letteratura più recente emerge che sentimenti di insicurezza esistenziale e ansia generalizzata possono essere indicati quali il primo ingrediente della ricetta; essi sarebbero anche in grado di distorcere i meccanismi di ragionamento e acquisizione delle informazioni. Peculiari tratti e difese narcisistiche unite a una condizione di isolamento e frustrazione sociale sono i composti del secondo ingrediente. Quest’ultimi tratti danno corpo a quelle ideazioni di stampo paranoideo, che colpiscono tanto l’attenzione dei media. Il terzo ingrediente è il bisogno di integrazione (e riconoscimento sociale), una spinta motivazionale incontenibile, autentico collante delle reti cospirazioniste
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