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1.
Bagherzadeh  S.  Maghooli  K.  Farhadi  J.  Zangeneh Soroush  M. 《Neurophysiology》2018,50(6):428-435
Neurophysiology - The problem of recognition of emotions in humans is still open from a few aspects. In our study, we used a deep learning method named stacked autoencoder to classify regions of...  相似文献   
2.
Neisseria meningitidis is efficiently phagocytosed by polymorphonuclear leukocytes (PMNS) following opsonization with opsonic antibodies; opsonophagocytosis is the primary mechanism for clearance of meningococci from the host. Thus, in testing meningococcal vaccines, the level of opsonophagocytic antibodies appears to correlate with vaccine-induced protection. Our previous studies demonstrated that the conjugation ofN. meningitidis serogroup A capsular polysaccharide (CPSA) to serogroup B outer membrane vesicle (OMV) could induce a high level of bactericidal antibody response against serogroup A meningococci in animals. The purpose of this study was to evaluate opsonophagocytic activity of the conjugate of CPSA to OMV (CPSA-OMV). In order to evaluate the potential efficacy of CPSA-OMV a flow cytometric opsonophagocytic assay was used. The conjugate and controls were injected intramuscularly into four groups of rabbits with boosters on days 14, 28 and 42 following primary immunization. The rabbits were bled prior to injection and two weeks after each injection. Opsonophagocytic activity of antibodies in hyperimmune sera through rabbit PMNS were measured with flow cytometer, using dihydrorhodamine-123 as a probe. The results indicated that our conjugate could induce a highly significant level of opsonophagocytic activity against serogroup A meningococci after 56 days compared to the control groups (P<0.05). We conclude that this conjugate represents a vaccine candidate against serogroups A and B meningococci after further investigation.  相似文献   
3.
A 3?×?2 factorial experiment consisting three levels (0, 200, and 400 μg/kg) of chromium (chromium picolinate) and two levels (0 and 250 mg/kg) of vitamin C was employed to evaluate the effects of these dietary supplements on performance, egg quality traits, and serum biochemical parameters of heat-stressed laying hens (Lohmann LSL-Lite) from 66 to 74 weeks of age. Feed intake increased when birds were given either 400 μg/kg chromium or 250 mg/kg vitamin C (P?<?0.05), but the birds that received both chromium and vitamin C consumed feed similar to those that received only chromium. Dietary treatments had no effect on egg production, egg mass, egg volume, feed conversion ratio, and body mass (P?>?0.05). The birds that fed on diet with chromium or vitamin C produced eggs with higher shell mass and thickness compared to the control. Both eggshell mass and thickness decreased when vitamin C and chromium were supplemented simultaneously, and birds given the diet supplemented with 400 μg/kg chromium and 250 mg/kg vitamin C had eggshell mass and thickness similar to those of the control group. The serum concentration of chromium increased due to increasing level of dietary chromium (P?<?0.05). The birds that received diet with chromium and vitamin C had higher serum concentrations of chromium compared to those that received only chromium (P?<?0.05). Similarly, the hens that received chromium and vitamin C had higher serum concentrations of calcium and phosphorus compared to the hens fed with other treatments (P?<?0.05). The birds given with supplemental chromium exhibited lower serum glucose, total cholesterol, and triglycerides concentrations but higher serum albumin and total protein concentrations compared to the other groups (P?<?0.05).  相似文献   
4.
Intra- and interindividual epigenetic variation in human germ cells   总被引:6,自引:0,他引:6       下载免费PDF全文
Epigenetics represents a secondary inheritance system that has been poorly investigated in human biology. The objective of this study was to perform a comprehensive analysis of DNA methylation variation between and within the germlines of normal males. First, methylated cytosines were mapped using bisulphite modification-based sequencing in the promoter regions of the following disease genes: presenilins (PSEN1 and PSEN2), breast cancer (BRCA1 and BRCA2), myotonic dystrophy (DM1), and Huntington disease (HD). Major epigenetic variation was detected within samples, since the majority of sperm cells of the same individual exhibited unique DNA methylation profiles. In the interindividual analysis, 41 of 61 pairwise comparisons revealed distinct DNA methylation profiles (P=.036 to 6.8 x 10(-14)). Second, a microarray-based epigenetic profiling of the same sperm samples was performed using a 12,198-feature CpG island microarray. The microarray analysis has identified numerous DNA methylation-variable positions in the germ cell genome. The largest degree of variation was detected within the promoter CpG islands and pericentromeric satellites among the single-copy DNA fragments and repetitive elements, respectively. A number of genes, such as EED, CTNNA2, CALM1, CDH13, and STMN2, exhibited age-related DNA methylation changes. Finally, allele-specific methylation patterns in CDH13 were detected. This study provides evidence for significant epigenetic variability in human germ cells, which warrants further research to determine whether such epigenetic patterns can be efficiently transmitted across generations and what impact inherited epigenetic individuality may have on phenotypic outcomes in health and disease.  相似文献   
5.
A simple, validated protocol consisting of a battery of tests is available to identify elderly patients with frailty syndrome. This syndrome of decreased reserve and resistance to stressors increases in incidence with increasing age. In the elderly, frailty may pursue a step-wise loss of function from non-frail to pre-frail to frail. We studied frailty in HIV-infected patients and found that ~20% are frail using the Fried phenotype using stringent criteria developed for the elderly1,2. In HIV infection the syndrome occurs at a younger age.HIV patients were checked for 1) unintentional weight loss; 2) slowness as determined by walking speed; 3) weakness as measured by a grip dynamometer; 4) exhaustion by responses to a depression scale; and 5) low physical activity was determined by assessing kilocalories expended in a week''s time. Pre-frailty was present with any two of five criteria and frailty was present if any three of the five criteria were abnormal.The tests take approximately 10-15 min to complete and they can be performed by medical assistants during routine clinic visits. Test results are scored by referring to standard tables. Understanding which of the five components contribute to frailty in an individual patient can allow the clinician to address relevant underlying problems, many of which are not evident in routine HIV clinic visits.  相似文献   
6.
OBJECTIVE: We investigated whether plasma concentrations of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) reflect impaired diastolic relaxation or its improvement after ACE inhibition. METHODS: 7 long-term Type 1 diabetic patients with normal systolic but impaired diastolic function and with sympathetic myocardial dysinnervation and 10 controls were included. Exercise tolerance and maximal O 2 uptake were evaluated by bicycle exercise prior to the study. ANP, BNP and norepinephrine/epinephrine (NE/E) were determined at baseline and at 80 % .VO2 max workload and after recovery, before and following 12 weeks of treatment with fosinopril (10 mg/d). RESULTS: Isovolumetric relaxation time (IVRT) and A/E wave ratio were increased by 26.7 +/- 11.5 % and 54.4 +/- 26.1 % in diabetic patients as compared to controls, respectively (p < 0.02). After 12 weeks of fosinopril treatment, no differences in IVRT or A/E wave ratio were detectable between groups. ANP was enhanced in Type 1 diabetes as compared to controls (baseline: 9.2 +/- 3.0 vs. 4.5 +/- 1.1; exercise: 22.4 +/- 7.7 vs. 7.9 +/- 1.2; recovery: 20.3. +/- 4.6 vs. 9.5 +/- 2.0 fmol/ml, p < 0.02). Fosinopril treatment abolished any differences between groups. BNP plasma levels did not differ between groups and no exercise dependent changes were observed. NE- and E-increase was greater at 80 % .VO2 max work load in Type 1 diabetes than in controls (p < 0.05). Again, fosinopril abolished differences between groups. CONCLUSION: In Type 1 diabetes, impaired diastolic function is associated with elevated ANP and catecholamine plasma levels that are normalized after ACE inhibition. Thus, ANP but not BNP appears to be a sensitive biochemical marker for early diastolic dysfunction in Type 1 diabetes.  相似文献   
7.
We study a chemical reaction-diffusion model (the Brusselator) for pattern formation on developing plant tips. A family of spherical cap domains is used to represent tip flattening during development. Applied to conifer embryos, we model the chemical prepatterning underlying cotyledon (“seed leaf”) formation, and demonstrate the dependence of patterns on tip flatness, radius, and precursor concentrations. Parameters for the Brusselator in spherical cap domains can be chosen to give supercritical pitchfork bifurcations of patterned solutions of the nonlinear reaction-diffusion system that correspond to the cotyledon patterns that appear on the flattening tips of conifer embryos.  相似文献   
8.

Background

For decades, contrast agents have been used to reduce longitudinal (T1) or transverse (T2) relaxation times. High toxicity of gadolinium-based contrast agents leads researchers to new T1 contrast agents. Manganese oxide (MnO) nanoparticle (NP) with the lower peril and good enough signal change ability has been offered as a new possibility for magnetic resonance imaging (MRI).

Methods

The synthesized NPs were investigated for physicochemical and biological properties by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscope, dynamic light scattering (DLS), inductively coupled plasma, enzyme-linked immunosorbent assay, and 3 T magnetic resonance imaging.

Results

Due to physical contact importance of T1 contrast agents with tissues' protons, extremely thin layer of the surfactant, less than 2 nm, was coated on NPs for aqueous stabilizing. The hydrophilic gentisic acid with low Dalton, around 154, did that role truly. Moreover, decreasing NP size to 5 nm which increases available surface for the proton relaxation is another important parameter to reach an appropriate longitudinal relaxation rate. The NPs didn't reveal any side effects on the cells, and cellular uptake was considerable.

Conclusions

The synthesized NPs represented a promising result in comparison to clinical gadolinium chelates, due to higher r1 relaxivity and lower toxicity.

General significance

In addition to considerable signal change and cellular uptake, Prussian blue was tried on MnO NPs for the initial time, which can be observed within cells by pale blue color.  相似文献   
9.
Brucellosis is a worldwide zoonosis and represents one of the most important public health problems in many countries, especially around the Mediterranean basin, Middle East, India and Central and South America. Currently subunit vaccines are being considered to develop effective vaccines for human which has been evidenced by vaccines currently available against the infections such as meningococcal diseases and influenza. The application of new adjuvants of microbial origins is also underway to design subunit vaccines promoting the immune responses to the antigenic determinant(s) of the vaccine. In order to explore the efficacy ofBrucella abortus lipopolysaccharide (LPS) combined with different adjuvants and proteins (as a vaccine candidate) in the induction of immune response as an effective and long-lasting immunity againstBrucella, we evaluated the outer membrane vesicle ofNeisseria meningitidis serogroup B (GBMOMV) as a subcutaneous adjuvant and a part of a brucellosis candidate vaccine to induce high titres of specific anti-Brucella abortus S99 LPS in animal model (mice). The obtained results were compared with complete and incomplete Freund’s adjuvants (CFA and IFA). LPS+GBMOMV was the most immunogenic compound that stimulated following the first injection and increase in IgG titre of about 3.90, 3.18 and 1.58 fold higher than that produced against LPS, LPS+IFA and LPS+CFA, respectively. The highest anti-LPS IgG titre was detected two weeks after the third injection (the day 42) of LPS+GBMOMV. Purified GBMOMV can be considered as a safe subcutaneous adjuvant and a part of a candidate vaccine when combined with lipopolysaccharide ofBrucella abortus S99.  相似文献   
10.
Portal infusion of glucose at rates approximating endogenous glucose production (EGP) causes paradoxical hypoglycemia in wild-type but not GLUT2 null mice, implying activation of a specific portal glucose sensor. To determine whether this occurs in humans, glucose containing [3-3H]glucose was infused intraduodenally at rates of 3.1 mg. kg-1. min-1 (n = 5), 1.55 mg. kg-1. min-1 (n = 9), or 0/0.1 mg. kg-1. min-1 (n = 9) for 7 h in healthy nondiabetic subjects. [6,6-2H2]glucose was infused intravenously to enable simultaneous measurement of EGP, glucose disappearance, and the rate of appearance of the intraduodenally infused glucose. Plasma glucose concentrations fell (P < 0.01) from 90 +/- 1 to 84 +/- 2 mg/dl during the 0/0.1 mg. kg-1. min-1 id infusions but increased (P < 0.001) to 104 +/- 5 and 107 +/- 3 mg/dl, respectively, during the 1.55 and 3.1 mg. kg-1. min-1 id infusions. In contrast, insulin increased (P < 0.05) during the 1.55 and 3.0 mg. kg-1. min-1 infusions, reaching a peak of 10 +/- 2 and 18 +/- 5 micro U/ml, respectively, by 2 h. Insulin concentrations then fell back to concentrations that no longer differed by study end (7 +/- 1 vs. 8 +/- 1 micro U/ml). This resulted in comparable suppression of EGP by study end (0.84 +/- 0.2 and 0.63 +/- 0.1 mg. kg-1. min-1). Glucose disappearance was higher (P < 0.01) during the final hour of the 3.1 than 1.55 mg. kg-1. min-1 id infusion (4.47 +/- 0.2 vs. 2.6 +/- 0.1 mg. kg-1. min-1), likely because of the slightly, but not significantly, higher glucose and insulin concentrations. We conclude that, in contrast to mice, selective portal glucose delivery at rates approximating EGP does not cause hypoglycemia in humans.  相似文献   
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