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1.
It is widely held that long-term memories are established by consolidation of newly acquired information into stable neural representations, a process that requires protein synthesis and synaptic plasticity. Plasticity within the nucleus accumbens (NAc), a major component of the ventral striatum, is thought to mediate instrumental learning processes and many aspects of drug addiction. Here we show that the inhibition of protein synthesis within the NAc disrupts consolidation of an appetitive instrumental learning task (lever-pressing for food) in rats. Post-trial infusions of anisomycin immediately after the first several training sessions prevented consolidation, whereas infusions delayed by 2 or 4 hours had no effect. However, if the rats were allowed to learn the task, the behavior was not sensitive to disruption by intra-accumbens anisomycin. Control infusions into the medial NAc shell or the dorsolateral striatum did not impair learning; in fact, an enhancement was observed in the latter case. These results show that de novo protein synthesis within the NAc is necessary for the consolidation, but not reconsolidation, of appetitive instrumental memories.  相似文献   
2.
Seminal oxidative stress (OS) is a major contributing factor to male infertility. Semen analysis cannot identify reactive oxygen species (ROS), which can be measured using a chemiluminescence assay. Measurement of redox potential provides a more comprehensive assessment of OS, although the test has yet to be fully validated. This study aimed to validate the MiOXsys analyser for measuring static oxidation–reduction potential (sORP). Results demonstrated that duplicate measurements must be taken, sensors must be batch tested, and sockets should be regularly changed to avoid inconsistency in measurement. Measurement of sORP using MiOXsys exhibited good reproducibility across different operators (p = 0.469), analysers (p = 0.963) and days (p = 0.942). It is not affected by mechanical agitation (p = 0.522) or snap freezing and thawing (p = 0.823). The stability of sORP over time requires further verification, particularly in samples with high initial sORP. Measurement is temperature sensitive between 2 and 37°C, significantly increasing with increasing temperature (p = 0.0004). MiOXsys is a more stable assay for assessing OS than chemiluminescence methods and permits greater flexibility for sample handling. MiOXsys could be implemented to complement semen analysis as part of routine diagnostic testing for male infertility and may be useful in identifying contributing factors to idiopathic infertility.  相似文献   
3.
Interleukin (IL)-1β is a key innate cytokine that is essential for immune activation and promoting the inflammatory process. However, abnormal elevation in IL-1β levels has been associated with unwanted clinical outcomes. IL-1β is the most extensively studied cytokine among the IL-1 family of cytokines and its role in pathology is well established. During the course of human immunodeficiency virus type 1 (HIV-1) infection, the level of this proinflammatory cytokine is increased in different anatomical compartments, particularly in lymphatic tissues, and this elevation is associated with disease progression. The aim of this review is to address the pathological roles play by IL-1β in the light of enhancing HIV-1 replication, driving immune cell depletion, and chronic immune activation. The role of IL-1β in HIV-1 transmission (sexually or vertically ‘from mother-to-child’) will also be discussed. Additionally, the impact of the available antiretroviral therapy regimens on the levels of IL-1β in HIV-1 treated patients is also discussed. Finally, we will provide a glance on how IL-1β could be targeted as a therapeutic strategy.  相似文献   
4.
Purpose: Severe acute toxicity limits the effective use of radiotherapy in patients who are radiosensitive, and it is not usually possible to identify these radiohypersensitive (R-H) individuals before treatment commences. Five such R-H patients were detected over a 3-year period. We undertook this study to determine whether the severe acute radiohypersensitivity of these five individuals showed any correlation with cellular and molecular parameters known to be abnormal in radiosensitivity-related syndromes such as ataxia–telangiectasia (A-T).

Methods and Materials: Lymphoblastoid cells were isolated from fresh blood from the 5 R-H individuals who had previously demonstrated clinical R-H at least 9 months prior to sampling. Lymphoblastoid cell lines (LCLs) were established to determine the extent of postradiation chromosomal aberrations, cell cycle delay, cell proliferation, and tumor suppressor p53 protein stabilization. The polymerase chain reaction (PCR) and protein truncation (PTT) assays were used to test for the possibility of mutations in the gene mutated in A-T, termed ATM.

Results: LCLs derived from R-H subjects retained a significantly higher degree of radiation-induced chromosomal aberrations when compared to normal control LCLs. p53 stabilization by ionizing radiation appeared normal in all but one R-H subject. There was no evidence of A-T gene truncation mutations in any of the R-H subjects tested.

Conclusions: All R-H subjects in this study had their cellular radiosensitivity confirmed by the chromosomal aberration assay. Delayed p53 stabilization at 4 hours postirradiation in one R-H subject suggested that different etiologies may apply in the radiohypersensitivity investigated in this study.  相似文献   

5.
6.
β-Thalassemia major (β-TM) is an inherited disease and efforts have been made in several countries to reduce the number of affected births. In the present study, we aimed to evaluate the Iranian thalassemia prevention program, considered to be an important program in the region. The time period of the present study ranges from 2007–2009, during which new thalassemic births and the relevant causes were evaluated throughout the country. A cross-sectional analytical study was conducted at the Iranian Blood Transfusion Organization (IBTO), Tehran, Iran. A questionnaire was forwarded to all blood centers of the IBTO so as to obtain information about the new cases of thalassemia and the causes of these thalassemic births. Provincial thalassemia societies also received the questionnaires so that screening and prenatal diagnosis (PND) errors would be recorded. The results showed that 755 new thalassemia cases were born during 2007–2009 with the average fall in affected thalassemia births of 80.82%. The main cause of the new births was attributed to unregistered “timeless religious marriages” based on the conventions of the Sunni community which accounted for 43.17% of all new cases mainly having occurred in Sistan & Baluchestan Province. Not using PND was evaluated to be another main cause. Although the prevention program has led to a great reduction in thalassemic births, new measures are required, including research on how to make the program compatible with social and economic conventions and norms of Sistan & Baluchestan Province. The province of Kohgiluyeh Boyer Ahmad also needs to be revisited in terms of the program efficacy.  相似文献   
7.
We propose a system able to synthesize automatically a classification model and a set of interpretable decision rules defined over a set of symbols, corresponding to frequent substructures of the input dataset. Given a preprocessing procedure which maps every input element into a fully labeled graph, the system solves the classification problem in the graph domain. The extracted rules are then able to characterize semantically the classes of the problem at hand. The structured data that we consider in this paper are images coming from classification datasets: they represent an effective proving ground for studying the ability of the system to extract interpretable classification rules. For this particular input domain, the preprocessing procedure is based on a flexible segmentation algorithm whose behavior is defined by a set of parameters. The core inference engine uses a parametric graph edit dissimilarity measure. A genetic algorithm is in charge of selecting suitable values for the parameters, in order to synthesize a classification model based on interpretable rules which maximize the generalization capability of the model. Decision rules are defined over a set of information granules in the graph domain, identified by a frequent substructures miner. We compare the system with two other state-of-the-art graph classifiers, evidencing both its main strengths and limits.  相似文献   
8.
To evaluate the effects of a cardiac rehabilitation program on heart rate recovery after percutaneous transluminal coronary angioplasty, a historical cohort study was performed on 436 patients of whom 285 were grouped on completion of 5, 10, or 24 training sessions. All 3 groups showed significant improvements in heart rate recovery, peak heart rate during treadmill testing, and end-training heart rate, from baseline to follow-up. Heart rate recovery on follow-up correlated significantly with the number of completed exercise sessions. The number of sessions, baseline ejection fraction, and age were independent predictors of mean post-training heart rate recovery. The cardiac rehabilitation program had a significant effect on peak heart rate and heart rate recovery, regardless of the underlying characteristics of the patients.  相似文献   
9.

Background:

Parasite lactate dehydrogenase (pLDH) is extensively employed as malaria rapid diagnostic tests (RDTs). Moreover, it is a well-known drug target candidate. However, the genetic diversity of this gene might influence performance of RDT kits and its drug target candidacy. This study aimed to determine polymorphism of pLDH gene from Iranian isolates of P. vivax and P. falciparum.

Methods:

Genomic DNA was extracted from whole blood of microscopically confirmed P. vivax and P. falciparum infected patients. pLDH gene of P. falciparum and P. vivax was amplified using conventional PCR from 43 symptomatic malaria patients from Sistan and Baluchistan Province, Southeast Iran from 2012 to 2013.

Results:

Sequence analysis of 15 P. vivax LDH showed fourteen had 100% identity with P. vivax Sal-1 and Belem strains. Two nucleotide substitutions were detected with only one resulted in amino acid change. Analysis of P. falciparum LDH sequences showed six of the seven sequences had 100% homology with P. falciparum 3D7 and Mzr-1. Moreover, PfLDH displayed three nucleotide changes that resulted in changing only one amino acid. PvLDH and PfLDH showed 75%–76% nucleotide and 90.4%–90.76% amino acid homology.

Conclusion:

pLDH gene from Iranian P. falciparum and P. vivax isolates displayed 98.8–100% homology with 1–3 nucleotide substitutions. This indicated this gene was relatively conserved. Additional studies can be done weather this genetic variation can influence the performance of pLDH based RDTs or not.  相似文献   
10.
It is believed that neuropathic pain results from aberrant neuronal discharges although some evidence suggests that the activation of glia cells contributes to pain after an injury to the nervous system. This study aimed to evaluate the role of microglial activation on the hyper‐responsiveness of wide dynamic range neurons (WDR) and Toll‐like receptor 4 (TLR4) expressions in a chronic constriction injury (CCI) model of neuropathic pain in rats. Adult male Wistar rats (230 ± 30 g) underwent surgery for induction of CCI neuropathy. Six days after surgery, administration of minocycline (10, 20, and 40 mg/kg, i.p.) was initiated and continued until day 14. After administration of the last dose of minocycline or saline, a behavioral test was conducted, then animals were sacrificed and lumbar segments of the spinal cord were collected for Western blot analysis of TLR4 expression. The electrophysiological properties of WDR neurons were investigated by single unit recordings in separate groups. The findings showed that after CCI, in parallel with thermal hyperalgesia, the expression of TLR4 in the spinal cord and the evoked response of the WDR neurons to electrical, mechanical, and thermal stimulation significantly increased. Post‐injury administration of minocycline effectively decreased thermal hyperalgesia, TLR4 expression, and hyper‐responsiveness of WDR neurons in CCI rats. The results of this study indicate that post‐injury, repeated administration of minocycline attenuated neuropathic pain by suppressing microglia activation and reducing WDR neuron hyper‐responsiveness. This study confirms that post‐injury modulation of microglial activity is a new strategy for treating neuropathic pain.  相似文献   
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