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131.
Interleukin 35 (IL-35), a cytokine mainly produced by regulatory T cells (Treg cells), is composed of an Epstein-Barr virus–induced gene 3 β-chain and an IL-12 p35 α-chain. IL-35 causes tumorigenicity in cancer, protects cancer cells against apoptosis, and facilitates cancer progression. However, a few reports have referred to its contradictory roles in cancer prevention. Therefore, the exact purpose of this cytokine in cancer development has become a fundamental question that needs to be answered. In this review, we explain the structure of IL-35 and its receptors and their different signaling pathways. Finally, the function of IL-35 in some cancers and the possible application of this cytokine in approaches for cancer therapy have been discussed.  相似文献   
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133.
Eighteen species and subspecies (34 accessions) of Allium sect. Acanthoprason and 11 species (17 accessions) belonging to other subgenera and sections of Allium were karyologically investigated and include first reports for 12 species. The examined plants of 47 accessions were diploid, three accessions of two species were tetraploid, and in the A. bisotunense accession, we found a mix of di- and triploid individuals. B chromosomes were found in 10 accessions. A basic chromosome number of x = 8 was confirmed for all investigated members of subg. Melanocrommyum and subg. Allium, and x = 9 for Allium tripedale of subg. Nectaroscordum. Idiograms were drawn for each accession, and metaphase images are presented illustrating observed chromosomal variations. Also, karyotype features and asymmetry parameters were calculated for all accessions. Chromosomal aberrations, e.g. aneuploid cells or loss of whole or parts of chromosome arms, were rarely observed. In general, the karyotypes showed low variation in inter- and intrachromosomal asymmetry especially inside of the taxonomic groups, though satellited chromosomes were good markers for subgenera and even specific for two studied sections of subg. Allium. Six different types of satellites were recognized, two of them were newly described: Type P was prevalent in subg. Melanocrommyum, and type O in sect. Codonoprasum. Statistical analyses were performed on five karyological parameters to test correct relationships and also to test previous grouping hypotheses. Although our data confirm distinct karyological characters for the subgenera investigated, the remarkable morphological diversity inside of subg. Melanocrommyum is not mirrored by striking karyological differences.  相似文献   
134.

Background

The development of CRISPR genome editing has transformed biomedical research. Most applications reported thus far rely upon the Cas9 protein from Streptococcus pyogenes SF370 (SpyCas9). With many RNA guides, wildtype SpyCas9 can induce significant levels of unintended mutations at near-cognate sites, necessitating substantial efforts toward the development of strategies to minimize off-target activity. Although the genome-editing potential of thousands of other Cas9 orthologs remains largely untapped, it is not known how many will require similarly extensive engineering to achieve single-site accuracy within large genomes. In addition to its off-targeting propensity, SpyCas9 is encoded by a relatively large open reading frame, limiting its utility in applications that require size-restricted delivery strategies such as adeno-associated virus vectors. In contrast, some genome-editing-validated Cas9 orthologs are considerably smaller and therefore better suited for viral delivery.

Results

Here we show that wildtype NmeCas9, when programmed with guide sequences of the natural length of 24 nucleotides, exhibits a nearly complete absence of unintended editing in human cells, even when targeting sites that are prone to off-target activity with wildtype SpyCas9. We also validate at least six variant protospacer adjacent motifs (PAMs), in addition to the preferred consensus PAM (5′-N4GATT-3′), for NmeCas9 genome editing in human cells.

Conclusions

Our results show that NmeCas9 is a naturally high-fidelity genome-editing enzyme and suggest that additional Cas9 orthologs may prove to exhibit similarly high accuracy, even without extensive engineering.
  相似文献   
135.
Silk fibroin nanoparticles (SFNPs) as a natural polymer have been utilized in biomedical applications such as suture, tissue engineering‐based scaffolds, and drug delivery carriers. Since there is little data regarding the toxicity effects on different cells and tissues, we aimed to determine the toxicity mechanisms of SFNPs on human lymphocytes and monocytes based on reliable methods. Our results showed that SFNPs (0.5, 1, and 2 mg/mL) induced oxidative stress via increasing reactive oxygen species production, mitochondrial membrane potential (?Ψ) collapse, which was correlated to cytochrome c release and Adenosine diphosphate (ADP)/Adenosine tri phosphate (ATP) ratio increase as well as lysosomal as another toxicity mechanism, which led to cytosolic release of lysosomal digestive proteases, phosphor lipases, and apoptosis signaling. Taken together, these data suggested that SFNPs toxicity was associated with mutual mitochondrial/lysosomal cross‐talk and oxidative stress on human lymphocytes and monocytes with activated apoptosis signaling.  相似文献   
136.
In biotechnological processes, often cell disruption has been an inevitable step as current host cells express most of the desired products intracellularly. Thus, an appropriate cell disruption technique must be selected considering different factors including the target product, process scale, and cell wall structure. In the current study, as a novel method, the efficacy of cell disruption via laser was tested qualitatively and quantitatively in batch and continuous systems, respectively. Laser-induced cell lysis can be a clean, rapid and convenient alternative to the other conventional disruption techniques. Our investigations in the continuous system with a flow rate of 800 μL/sec proved efficient (~ 90%) Pichia pastoris cell disruption at the wavenumber 1,064 nm with the energy input of 284 mW after four complete rounds of circulation. The main mechanism of cell disruption is assumed to be thermolysis via instant heat increase in the laser-treated spot. The results of the current study showed that continuous laser system could be applied in laboratory and industry scale for cell disruption.  相似文献   
137.

Objective

In this study, transfection efficiency of human papillomavirus (HPV) E7 DNA and protein constructs into HEK-293T normal cell line, and A549 and TC-1 tumor cell lines was evaluated by four delivery systems including supercharge GFP, hPP10 cell penetrating peptide, TurboFect and Lipofectamine using fluorescence microscopy and flow cytometry.

Results

The results indicated that Lipofectamine 2000 and TurboFect produced more effective transfection for GFP and E7-GFP DNA constructs in HEK-293T cells compared to in A549 and TC-1 cells (p?<?0.05). In contrast, the supercharge GFP was efficient for E7 DNA and E7 protein delivery in both normal cell (~?83.94 and ~?77.01% for HEK-293T), and cancer cells (~?71.69 and ~?67.19% for TC-1, and ~?73.86 and ~?67.49% for A549), respectively. Indeed, in these cell lines, transfection efficiency by +36 GFP reached ~?60–80%. Moreover, the hPP10 produced the best transfection result for E7-GFP protein in HEK-293T cells (~?63.66%) compared to TurboFect (~?32.95%); however, the efficiency level of hPP10 was only ~?17.51 and ~?16.36% in TC-1 and A549 cells.

Conclusions

Our data suggested that the supercharge GFP is the most suitable transfection vehicle for DNA and protein delivery into TC-1 and A549 tumor cell lines compared to other carriers.
  相似文献   
138.
139.
In this paper, we redescribe Gaeolaelaps deinos (Zeman 1982) based on morphological characters of female and male specimens collected from nests of Lasius sp. (Hymenoptera: Formicidae) Khuzestan and Chaharmahal va Bakhtiari Provinces, Iran, and based on its holotype photos. We also present an identification key for Gaeolaelaps aculeifer-like species group from Iran.  相似文献   
140.
We explored the population systems of Pelophylax bedriagae (Camerano, 1882) in northwestern, western and southwestern Iran. Statistical significance for a hypothesis of sexual dimorphism of the frogs was tested using t-test and multivariate analysis of variances (MANOVA). Due to lack of sexual differences between the male and female frogs, the data of both sexes were pooled for further analysis. Taxonomic relationships among local populations were investigated using discriminate analysis (by stepwise method) with iterative sample assignment. The multivariate morphometric analyses revealed that the range of P. bedriagae extends to western Iran. The next step was to analyze the advertisement call (five standard parameters: call duration, number of pulse groups per call, duration of pulse groups, interval between pulse groups, and intercall interval) of the water frogs inhabiting three sites in western Iran. Rigorous application of the bioacoustic method removes all doubt that these three sites are inhabited by the same species, which on the basis of priority of nomenclature should be called P. bedriagae.  相似文献   
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