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991.

Mixed (polyclonal) infections are one of the main problems in tuberculosis (TB) management. The best available method for detecting polyclonal infections in TB is mycobacterial interspersed repetitive unit–variable number tandem repeat (MIRU–VNTR). According to multiple studies, MIRU–VNTR method can be applied to detect TB-related polyclonal infections in sputum samples or cultures. Setup of MIRU–VNTR on smear slides can be an efficient approach, regardless of the limitations of cultures and sputum samples in many laboratories. The present study aimed at investigating the diagnostic potential of MIRU–VNTR on smear slides in detecting mixed infections. Ziehl–Neelsen-stained microscopic slides were prepared from 14 clinical specimens. For amplifying 24 MIRU–VNTR loci, PCR assay was performed on the smear slides, clinical specimens, and cultures. Based on the 24-locus MIRU–VNTR analysis, polyclonal infections were reported in 42.85% of smear slides, while the corresponding rate was estimated at 57.1% (8/14) in the clinical samples. In the corresponding cultures, the rate of mixed infection was 7.14% (1/14). Use of smear slides can be a safe option for transferring clinical specimens between environmental and reference laboratories. Considering their significant impact on TB treatment, it is essential to diagnose mixed infections in low-resource countries with a high prevalence of mixed infections. The present findings show that direct MIRU–VNTR on smear slides can be conveniently used for the detection of mixed infections.

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992.
Tachykinins (TKs) are a family of neuropeptides mainly expressed by neuronal and non-neuronal cell types, especially immune cells. Expression of TKs receptors on immune cell surfaces, their involvement in immune-related disorders, and therefore, understanding their immunomodulatory roles have become of particular interest to researchers. In fact, the precise understanding of TKs intervention in the immune system would help to design novel therapeutic approaches for patients suffering from immune disorders. The present review summarizes studies on TKs function as modulators of the immune system by reviewing their roles in generation, activation, development, and migration of immune cells. Also, it discusses TKs involvement in three main cellular mechanisms including inflammation, apoptosis, and proliferation.  相似文献   
993.
Abstract

Studies on the anti-cancer effects of nanomaterials are a very important step in the clinical practice and treatment of cancerous tissues. Since IONPs have a high potential for cancer treatment, their anti-cancer properties can help us to resolve some of the therapeutic problems. For this purpose, in addition to synthesizing two types of IONPs including MN and MHN, Lf coating was used to increase their anti-cancer activity. MN and MHN were synthesized by hydrothermal and thermal methods, respectively, and their physicochemical properties were examined by SEM, zeta-potential, DLS, FTIR, TGA, and magnetism saturation. Molecular modelling was also done to model two steps of functionalization on the IONPs surface. In order to prove the biological activity of fabricated NPs in vitro, experimental assays of NP cytotoxicity were performed on breast cancerous cells (4T1) by MTT and ROS assays. It was found that the MN and MHN have a diameter around 24 and 33?nm, respectively. Also, the hydrodynamic radius of MN and MHN coated with Lf were 30 and 38?nm, and their zeta potential values at pH = 7.5 were ?5.3 and ?4.2?mV, respectively. Besides, the results of TGA, magnetism saturation and FTIR showed that Lf was successfully loaded onto NPs. Molecular modelling investigation depicted that dimethylamine moiety of the linker provides an intense reactive region for non-bonding linkages with Lf molecules. Cellular studies exhibited that Lf increased the toxicity of NPs and synthesized Lf-MNs provide the highest potency both on mortality and ROS level. This research may provide promising data for development of potential anticancer agents.

Communicated by Ramaswamy H. Sarma  相似文献   
994.
COVID-19 can present with a variety of clinical features, ranging from asymptomatic or mild respiratory symptoms to fulminant acute respiratory distress syndrome (ARDS) depending on the host's immune responses and the extent of the associated pathologies. This implies that several measures need to be taken to limit severely impairing symptoms caused by viral-induced pathology in vital organs. Opioids are most exploited for their analgesic effects but their usage in the palliation of dyspnoea, immunomodulation and lysosomotropism may represent potential usages of opioids in COVID-19. Here, we describe the mechanisms involved in each of these potential usages, highlighting the benefits of using opioids in the treatment of ARDS from SARS-CoV-2 infection.  相似文献   
995.
996.
Biological systems like cells, bacteria, chloroplasts and other micro-organisms could exchange quantum particles like electrons, photons and gravitational waves and have large distant information teleportation. This is because that their DNAs and membranes are formed from quantum particles like electrons and protons and by their motions, some currents and waves are emerged. These waves have the main role in information teleportation. There are different methods which could be used for quantum information teleportation in biological system. Some of these mechanisms are: 1. Microbes, micro-bubbles and some other biological molecules like to form some biological lines specially near the cellular gates. Also, some biological lines may be formed between two cells. These biological lines could play the role of wires which transmit information from a place to another one. For example, some signatures of this quantum information teleportation could be seen in biological lines which are emerged near the plant cell walls or gates or close to chloroplasts. Chloroplasts shoot some spinors which maybe confined within the micro-bubbles or absorb by microbes. These bubbles and microbes may join to each other and form some biological lines which may be strengthen from a plant cell to another. These biological lines could be seen near the plant cell walls or on a metal which connects two parts of a leaf. 2. Some another signatures of “quantum photon exchange or quantum information teleportation” could be seen between microbes under the objective lenses and macro-objects on the eye lenses of a light microscope. It seems that as microscope make big images from microbes for us, produce small pictures of macro-objects for microbes such as they could diagnose them and interact with them. This property could be used in controlling microbes. 3. Another way for controlling microbes is using of virtual shapes which are induced by a special light source. For example, using a multi-gonal lamp, one can induce multi-gonal shape within the micro-bubbles. Also, this special lamp could force microbes and micro-bubbles to build multi-gonal colonies on a metal-glass slide. Maybe, by using this property, one can build a light source with the shape of anti-microbial matter and induce anti-microbial property within micro-bubbles. 4. Another main way for quantum teleportation is using of gravitational holes which may be emerged by increasing concentration of microbes and heavy cells in some points. These holes absorb microbes and micro-bubbles and conduct them to the heavy cells. Usually, there are some white holes near these dark holes which as a proposal, one can assume that these white holes are another end of gravitational holes and emit photons which are entered from dark end. 5. And finally, a very main mechanism for quantum information teleportation with microbes and controlling them is using of a holography and inducing virtual microbes and biological molecules in biological systems. For example, by a combinations of two lights with different colors under a light microscope in a dark room, one may induce some non-virtual microbes in biological systems such as each microbe interacts with a virtual microbe. This is because that light waves take photos of microbes, collide with lenses of microscopes and return to the slide and form virtual microbes or biological molecules. This technique could be used in curing diseases. Although, results of our experiments show the correctness of these mechanisms and theories, however, for the moment, we propose them only as a proposal and hypothesis and hope that other scientists do similar experiments. Also, some of our experiments may be at preliminary stages; however they could be used as a hypothesis, proposal and guidance.  相似文献   
997.
Probiotics and Antimicrobial Proteins - Hepatic stellate cell (HSC) activation is a key phenomenon in development of liver fibrosis. Recently, Akkermansia muciniphila has been introduced as a...  相似文献   
998.
Quasispecies variants and recombination were studied longitudinally in an emergent outbreak of beak and feather disease virus (BFDV) infection in the orange-bellied parrot (Neophema chrysogaster). Detailed health monitoring and the small population size (<300 individuals) of this critically endangered bird provided an opportunity to longitudinally track viral replication and mutation events occurring in a circular, single-stranded DNA virus over a period of four years within a novel bottleneck population. Optimized PCR was used with different combinations of primers, primer walking, direct amplicon sequencing and sequencing of cloned amplicons to analyze BFDV genome variants. Analysis of complete viral genomes (n = 16) and Rep gene sequences (n = 35) revealed that the outbreak was associated with mutations in functionally important regions of the normally conserved Rep gene and immunogenic capsid (Cap) gene with a high evolutionary rate (3.41×10−3 subs/site/year) approaching that for RNA viruses; simultaneously we observed significant evidence of recombination hotspots between two distinct progenitor genotypes within orange-bellied parrots indicating early cross-transmission of BFDV in the population. Multiple quasispecies variants were also demonstrated with at least 13 genotypic variants identified in four different individual birds, with one containing up to seven genetic variants. Preferential PCR amplification of variants was also detected. Our findings suggest that the high degree of genetic variation within the BFDV species as a whole is reflected in evolutionary dynamics within individually infected birds as quasispecies variation, particularly when BFDV jumps from one host species to another.  相似文献   
999.

Background

The rate of human immunodeficiency virus type 1 (HIV-1) infection in Iran has increased dramatically in the past few years. While the earliest cases were among hemophiliacs, injection drug users (IDUs) fuel the current epidemic. Previous molecular epidemiological analysis found that subtype A was most common among IDUs but more recent studies suggest CRF_35AD may be more prevalent now. To gain a better understanding of the molecular epidemiology of HIV-1 infection in Iran, we analyzed all Iranian HIV sequence data from the Los Alamos National Laboratory.

Methods

All Iranian HIV sequences from subtyping studies with pol, gag, env and full-length HIV-1 genome sequences registered in the HIV databases (www.hiv.lanl.gov) between 2006 and 2013 were downloaded. Phylogenetic trees of each region were constructed using Neighbor-Joining (NJ) and Maximum Parsimony methods.

Results

A total of 475 HIV sequences were analyzed. Overall, 78% of sequences were CRF_35AD. By gene region, CRF_35AD comprised 83% of HIV-1 pol, 62% of env, 78% of gag, and 90% of full-length genome sequences analyzed. There were 240 sequences re-categorized as CRF_AD. The proportion of CRF_35AD sequences categorized by the present study is nearly double the proportion of what had been reported.

Conclusions

Phylogenetic analysis indicates HIV-1 subtype CRF_35AD is the predominant circulating strain in Iran. This result differed from previous studies that reported subtype A as most prevalent in HIV- infected patients but confirmed other studies which reported CRF_35AD as predominant among IDUs. The observed epidemiological connection between HIV strains circulating in Iran and Afghanistan may be due to drug trafficking and/or immigration between the two countries. This finding suggests the possible origins and transmission dynamics of HIV/AIDS within Iran and provides useful information for designing control and intervention strategies.  相似文献   
1000.

Background

Novel vaccination approaches are needed to prevent leishmaniasis. Live attenuated vaccines are the gold standard for protection against intracellular pathogens such as Leishmania and there have been new developments in this field. The nonpathogenic to humans lizard protozoan parasite, Leishmania (L) tarentolae, has been used effectively as a vaccine platform against visceral leishmaniasis in experimental animal models. Correspondingly, pre-exposure to sand fly saliva or immunization with a salivary protein has been shown to protect mice against cutaneous leishmaniasis.

Methodology/Principal Findings

Here, we tested the efficacy of a novel combination of established protective parasite antigens expressed by L. tarentolae together with a sand fly salivary antigen as a vaccine strategy against L. major infection. The immunogenicity and protective efficacy of different DNA/Live and Live/Live prime-boost vaccination modalities with live recombinant L. tarentolae stably expressing cysteine proteinases (type I and II, CPA/CPB) and PpSP15, an immunogenic salivary protein from Phlebotomus papatasi, a natural vector of L. major, were tested both in susceptible BALB/c and resistant C57BL/6 mice. Both humoral and cellular immune responses were assessed before challenge and at 3 and 10 weeks after Leishmania infection. In both strains of mice, the strongest protective effect was observed when priming with PpSP15 DNA and boosting with PpSP15 DNA and live recombinant L. tarentolae stably expressing cysteine proteinase genes.

Conclusion/Significance

The present study is the first to use a combination of recombinant L. tarentolae with a sand fly salivary antigen (PpSP15) and represents a novel promising vaccination approach against leishmaniasis.  相似文献   
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