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211.
Unexplained recurrent spontaneous abortion (URSA) has been assumed to be caused by a defect in maternal immunological tolerance to the fetus. Human amniotic epithelial cells (hAECs) have stem cell-like features and the ability to modulate the innate and adoptive immune responses. This study aimed to investigate whether hAECs have immunomodulatory effects on naive CD4+ T cells from URSA patients. hAECs were obtained from 15 healthy pregnant women and phenotypic profile of hAECs was determined by flow cytometry. Naive CD4+ T cells were isolated from 25 URSA patients using an immunomagnetic separation method. Naive T cells were stimulated with anti-CD3/anti-CD28 antibodies and co-cultured with different numbers of hAECs for 3 and 6 days. Immunomodulatory effect of hAECs on activation of stimulated T cell was assessed by flow cytometry and Enzyme-linked immunoasorbent assay (ELISA). The hAECs effect on pro-inflammatory cytokines production of activated T cells was also measured by ELISA. Our results indicated that hAECs significantly inhibited the activation of naive T cells in a dose-dependent manner (p?<?0.0001–0.05). They significantly reduced the production of transforming growth factor-beta1 (TGF-β1) of stimulated CD4+T cells (p?<?0.0001–0.05). Moreover, hAECs had potent immunomodulatory effects on the production of interferon-gamma (IFN-γ) and interleukin-17A (IL-17A) of activated T cells (p?<?0.0001–0.01). These findings suggest that hAECs may be a suitable cell source to modulate abnormal immune responses in women with URSA.  相似文献   
212.
Catalytic combustion of hydrocarbons is an important technology to produce energy. Compared to conventional flame combustion, the catalyst enables this process to operate at lower temperatures; hence, reducing the energy required for efficient combustion. The reaction and activation energies of direct combustion of hydrocarbons (CH?→?C?+?H) on a series of metal surfaces were investigated using density functional theory (DFT). The data obtained for the Ag, Au, Al, Cu, Rh, Pt, and Pd surfaces were used to investigate the validity of the Brønsted-Evans-Polanyi (BEP) and transition state scaling (TSS) relations for this reaction on these surfaces. These relations were found to be valid (R2?=?0.94 for the BEP correlation and R2?=?1.0 for the TSS correlation) and were therefore used to estimate the energetics of the combustion reaction on Ni, Co, and Fe surfaces. It was found that the estimated transition state and activation energies (ETS?=??69.70 eV and Ea?=?1.20 eV for Ni, ETS?=??87.93 eV and Ea?=?1.08 eV for Co and ETS?=??92.45 eV and Ea?=?0.83 eV for Fe) are in agreement with those obtained by DFT calculations (ETS?=??69.98 eV and Ea?=?1.23 eV for Ni, ETS?=??87.88 eV and Ea?=?1.08 eV for Co and ETS?=??92.57 eV and Ea?=?0.79 eV for Fe). Therefore, these relations can be used to predict energetics of this reaction on these surfaces without doing the time consuming transition state calculations. Also, the calculations show that the activation barrier for CH dissociation decreases in the order Ag ? Au ? Al ? Cu ? Pt ? Pd ? Ni?>?Co?>?Rh?>?Fe.  相似文献   
213.

Background aims

With the support of five established scientific organizations, this report, the seventh of its kind, describes activity in Europe for the years 2014 and 2015 in the area of cellular and tissue-engineered therapies, excluding hematopoietic stem cell (HSC) treatments for the reconstitution of hematopoiesis.

Methods

In 2015 [respectively 2014], 205 [276] teams from 32 countries responded to the cellular and tissue-engineered therapy survey; 178 [126] teams reported treating 3686 [2665] patients.

Results

Indications were musculoskeletal/rheumatological disorders (32% [33%]), cardiovascular disorders (12% [21%]), hematology/oncology (predominantly prevention or treatment of graft versus host disease and HSC graft enhancement; 20% [20%]), neurological disorders (4% [6%]), gastrointestinal disorders (<1% [1%]) and other indications (31% [20%]). The majority of autologous cells (60% [73%]) were used to treat musculoskeletal/rheumatological (44% [36%]) disorders, whereas allogeneic cells were used mainly for hematology/oncology (61% [68%]). The reported cell types were mesenchymal stromal cells (40% [49%]), chondrocytes (13% [6%]), hematopoietic stem cells (12% [23%]), dermal fibroblasts (8% [3%]), dendritic cells (2% [2%]), keratinocytes (1% [2%]) and others (24% [15%]). Cells were expanded in vitro in 63% [40%] of the treatments, sorted in 16% [6%] of the cases and rarely transduced (<1%). Cells were delivered predominantly as suspension 43% [51%], intravenously or intra-arterially (30% [30%]), or using a membrane/scaffold (25% [19%]).

Discussion

The data are compared with those from previous years to identify trends in a still unpredictably evolving field. Perspectives of representatives from plastic surgery practitioners, Iran and ISCT are presented (contributing authors D.A. Barbara, B. Hossein and W.L. Mark, respectively).  相似文献   
214.
215.
Induced plant responses to herbivory can alter plant quality and influence subsequent interactions with organisms that use that plant as food source. In this study, we conducted several experiments in order to understand whether preference and performance of the cotton aphid, Aphis gossypii (Hem: Aphididae) and the spider mite, Tetranychus urticae (Acari: Tetranychidae) are affected by the previous herbivory of conspecific or heterospecific species on cucumber plants. Longevity, fecundity and pre-imaginal development time were measured as performance criteria. In addition, we explored whether these effects are local or systemic. In the case of performance experiments, the results varied from negative to neutral depending on the performance criteria, no positive effect was observed in studied interactions. Also, depending on performance criteria, the previous herbivory affected the plant systemically, or locally. Results of preference experiments indicated that mites and aphids prefer to settle and produce offspring on control leaf disc to prevent detrimental effects of the previous herbivory. Spider mites showed a stronger preference than aphids in the detection of induced leaf discs, which resulted in more mites being present and laying more egg on control leaf disc in both local and systemic treatments. Performing both preference and performance experiments, not only reveals the effect of herbivores on each other's mediated by the plant but also reveals more information about the sensitivity of herbivores to change in the quality of their host.  相似文献   
216.
Blackleg disease of Brassica napus caused by Leptosphaeria maculans (Lm) is largely controlled by the deployment of race‐specific resistance (R) genes. However, selection pressure exerted by R genes causes Lm to adapt and give rise to new virulent strains through mutation and deletion of effector genes. Therefore, a knowledge of effector gene function is necessary for the effective management of the disease. Here, we report the cloning of Lm effector AvrLm9 which is recognized by the resistance gene Rlm9 in B. napus cultivar Goéland. AvrLm9 was mapped to scaffold 7 of the Lm genome, co‐segregating with the previously reported AvrLm5 (previously known as AvrLmJ1). Comparison of AvrLm5 alleles amongst the 37 re‐sequenced Lm isolates and transgenic complementation identified a single point mutation correlating with the AvrLm9 phenotype. Therefore, we renamed this gene as AvrLm5‐9 to reflect the dual specificity of this locus. Avrlm5‐9 transgenic isolates were avirulent when inoculated on the B. napus cultivar Goéland. The expression of AvrLm5‐9 during infection was monitored by RNA sequencing. The recognition of AvrLm5‐9 by Rlm9 is masked in the presence of AvrLm4‐7, another Lm effector. AvrLm5‐9 and AvrLm4‐7 do not interact, and AvrLm5‐9 is expressed in the presence of AvrLm4‐7. AvrLm5‐9 is the second Lm effector for which host recognition is masked by AvrLm4‐7. An understanding of this complex interaction will provide new opportunities for the engineering of broad‐spectrum recognition.  相似文献   
217.
Human papillomavirus (HPV) is a common viral infection worldwide associated with a variety of cancers. The integration of the HPV genome in these patients causes chromosomal instability and triggers carcinogenesis. The aim of this study was to investigate the HPV-16 genome physical status in four major cancers related to HPV infection. Formalin-fixed paraffin-embedded blocks from our previous projects on head and neck, colorectal, penile, and cervical cancers were collected, and HPV-16–positive specimens were used for further analysis. The DNA extraction copy number of E2 and E7 genes was calculated by qualitative real-time PCR method. Serially diluted standards that were cloned in PUC57 plasmid were used. Standard curve and melting curve analysis was used for quantification. Of the 672 specimens studied, 76 (11.3%) were HPV-16 positive. We found that 35.6% (16/45) were integrated. Statistical analysis showed that there were significant correlations between integration of HPV-16 and cervical cancer end-stage carcinogenesis (P < .0001), episomal form, and ASCUS lesions (P = .045). Significant correlation in penile cancer patients was seen between the episomal form and high-grade cancer stage (P = .037). Integration is a major factor in the carcinogenesis mechanism of HPV and has different prevalence in various cancers with a higher rate in progression except in penile cancer.  相似文献   
218.
The focus of this study is the enhancement of microalgae growth rate using spectral conversion of green light. For this purpose, three reactors were considered and fluorescent pigment Rhodamine 6G was dissolved in a thermoplastic acrylic resin, the mixture was then applied on the front side of the first reactor, and on a mirror located at the rear side of the second one. Comparing their maximum specific growth rate (μ max) of Chlorella sp. to that in the third (uncoated) reactor, the former resulted in an increase up to 15% while the latter in decrease to at least 30%. Also, the rear side coated reactor showed up to 50% increase in biomass productivity rate (P) in early 4 days of experiment. However, this value decreased over time and the uncoated reactor in 12 days exhibited higher biomass productivity rate.  相似文献   
219.
In the present research, the binding properties of diazinon (DZN), as an organophosphorus herbicide, to human serum albumin (HSA) were investigated using combination of spectroscopic, electrochemistry, and molecular modeling techniques. Changes in the UV–Vis and FT-IR spectra were observed upon ligand binding along with a significant degree of tryptophan fluorescence quenching on complex formation. The obtained results from spectroscopic and electrochemistry experiments along with the computational studies suggest that DZN binds to residues located in subdomains IIA of HSA with binding constant about 1410.9 M?1 at 300 K. From the thermodynamic parameters calculated according to the van’t Hoff equation, the enthalpy change ΔH° and entropy change ΔS° were found to be ?16.695 and 0.116 KJ/mol K, respectively. The primary binding pattern is determined by hydrophobic interaction and hydrogen binding occurring in so-called site I of HSA. DZN could slightly alter the secondary structure of HSA. All of experimental results are supported by computational techniques such as docking and molecular dynamics simulation using a HSA crystal model.  相似文献   
220.
Intraspecific aggression is one of the most common causes of death in leopards. Here, we report four cases of intraspecific killing amongst Persian Leopards (Panthera pardus saxicolor) in Iran. A young male leopard was found on 7 June 2008 which, according to camera trap images, had been killed by an adult male over a Red Deer (Cervus elaphus) kill, with trauma to his neck in Dorfak No-Hunting Area. A young female that had been fitted with a satellite GPS collar on 6 December 2015 in Tandoureh National Park died on 29 January 2016 at a site where an Urial Sheep (Ovis orientalis) ram had been freshly killed. Necropsy results, footprints at the scene of death and camera trap footage all supported the deduction that the animal was killed by a larger female leopard at the kill site. On 13 January 2017, a young, partially eaten female leopard was found with double puncture on the side of her throat. Finally, a rehabilitated adult female fitted with a satellite GPS collar found on 19 December 2017 with a double puncture on her head with several trauma and haemorrhages on her back. These instances seem to be the first documented reports of intraspecific killing among free-ranging leopards in Asia.  相似文献   
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