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971.
Ha Hoang-Duc Quyen Pham-Huy Thuc Vu-Minh Sy Duong-Quy 《The Yale journal of biology and medicine》2020,93(5):657
Introduction: The correlation between alveolar nitric oxide (CANO) and the severity of interstitial lung disease (ILD) evaluated by high resolution computed tomography (HRCT) has not been well demonstrated. Methods: It was a perspective and observational study, including patients with diagnosed systemic sclerosis (SSc). They performed lung function testing (LFT), exhaled nitric oxide (NO) measurements, exercise testing, chest X-ray, and HRCT. Study patients were divided into SSc with ILD (SSc-ILD+) or without ILD (SSc-ILD-). SSC-ILD+ patients were revisited after 6 months and 12 months to complete the study. Results: Thirty-one control subjects and 74 patients with SSc (33 SSc-ILD- and 41 SSc-ILD+) were included. Forty-one SSc-ILD+ patients were followed-up at 6 months and 12 months. Lung functional parameters of patients with SSc-ILD+ were lower than that of SSc-ILD- patients. The level of CANO was significantly higher in SSc-ILD+ than SSc-ILD- patients (8.6 ± 2.5 vs 4.2 ± 1.3 ppb and P<0.01). Warrick and Goldin scores of patients with SSc-ILD+ were respectively 16.5 ± 5.2 and 12.7 ± 4.3. Warrick scores were reduced after 6 and 12 months of follow-up vs at inclusion (12.4 ± 4.3 and 9.1 ± 3.2 vs 16.5 ± 5.2; P<0.05, P<0.01, and P<0.05; respectively). ΔWarrick and ΔGoldin scores were significantly and inversely correlated with ΔFVC, ΔTLC, ΔTLCO, ΔVO2 max; that was also correlated with ΔCANO (R= 0.783, P<0.01 and R= 0.719 and P<0.05). Conclusion: CANO is a relevant biomarker for the diagnosis of ILD in patients with SSc, especially in combination with HRCT. 相似文献
972.
Sua Lee Yohan Park Seong Gyu Kim Eun Jeong Ko Byung Ha Chung Chul Woo Yang 《Microbiology and immunology》2020,64(5):356-365
Cytomegalovirus (CMV) infection is associated with Pneumocystis jirovecii pneumonia (PJP) in kidney transplant recipients (KTRs), but its impact on clinical severity and outcomes in KTRs with PJP is unknown. We reviewed 1994 medical records of KTRs from January 1997 to March 2019. PJP or CMV infection was diagnosed by polymerase chain reaction or culturing using blood or respiratory specimens. We divided patients into PJP and PJP+CMV groups, and evaluated the clinical severity and outcomes. Fifty two patients had PJP (2.6%) in the whole study cohort. Among patients with PJP, 38 (73.1%) had PJP alone and 14 (26.9%) had combined PJP and CMV co-infection. The PJP+CMV group showed worse laboratory findings (serum albumin and C-reactive protein, P = 0.010 for both) and higher requirement of continuous renal replacement therapy than the PJP group (P = 0.050). The pneumonia severity was worse in the PJP+CMV group than in the PJP group (P < 0.05), and CMV infection was a high risk factor of pneumonia severity (odds ratio 16.0; P = 0.002). The graft function was worse in the PJP+CMV group (P < 0.001), and the incidence of graft failure was higher in the PJP+CMV group than in the PJP group (85.7% vs 36.8%; P < 0.001). Mortality was double in the PJP+CMV group than in the PJP group, but not statistically significant (21.4% vs 10.5%; P = 0.370). Our results show that approximately one in four patients with PJP after kidney transplantation develops CMV with increased clinical severity and risk of graft failure. The possibility of increased clinical severity and worse clinical outcomes by CMV co-infection should be considered in KTRs with PJP. 相似文献
973.
Journal of Plant Growth Regulation - The primary factors that determine the longevity of cut roses are variable and depend on a cultivar’s sensitivity to ethylene. The vase life of... 相似文献
974.
David L. Slager Kevin L. Epperly Renee R. Ha Sievert Rohwer Chris Wood Caroline Van Hemert John Klicka 《Molecular ecology》2020,29(5):956-969
Most species and therefore most hybrid zones have historically been defined using phenotypic characters. However, both speciation and hybridization can occur with negligible morphological differentiation. Recently developed genomic tools provide the means to better understand cryptic speciation and hybridization. The Northwestern Crow (Corvus caurinus) and American Crow (Corvus brachyrhynchos) are continuously distributed sister taxa that lack reliable traditional characters for identification. In this first population genomic study of Northwestern and American crows, we use genomic SNPs (nuDNA) and mtDNA to investigate the degree of genetic differentiation between these crows and the extent to which they may hybridize. Our results indicate that American and Northwestern crows have distinct evolutionary histories, supported by two nuDNA ancestry clusters and two 1.1%‐divergent mtDNA clades dating to the late Pleistocene, when glacial advances may have isolated crow populations in separate refugia. We document extensive hybridization, with geographic overlap of mtDNA clades and admixture of nuDNA across >900 km of western Washington and western British Columbia. This broad hybrid zone consists of late‐generation hybrids and backcrosses, but not recent (e.g., F1) hybrids. Nuclear DNA and mtDNA clines had concordant widths and were both centred in southwestern British Columbia, farther north than previously postulated. Overall, our results suggest a history of reticulate evolution in American and Northwestern crows, perhaps due to recurring neutral expansion(s) from Pleistocene glacial refugia followed by lineage fusion(s). However, we do not rule out a contributing role for more recent potential drivers of hybridization, such as expansion into human‐modified habitats. 相似文献
975.
Soyoun Um Jueun Ha Soo Jin Choi Wonil Oh Hye Jin Jin 《World journal of stem cells》2020,12(12):1511-1528
Umbilical cord blood (UCB) is a primitive and abundant source of mesenchymal stem cells (MSCs). UCB-derived MSCs have a broad and efficient therapeutic capacity to treat various diseases and disorders. Despite the high latent self-renewal and differentiation capacity of these cells, the safety, efficacy, and yield of MSCs expanded for ex vivo clinical applications remains a concern. However, immunomodulatory effects have emerged in various disease models, exhibiting specific mechanisms of action, such as cell migration and homing, angiogenesis, anti-apoptosis, proliferation, anti-cancer, anti-fibrosis, anti-inflammation and tissue regeneration. Herein, we review the current literature pertaining to the UCB-derived MSC application as potential treatment strategies, and discuss the concerns regarding the safety and mass production issues in future applications. 相似文献
976.
Jong Min Lee Ha Young Chung Kyung Il Kim Ki Hyun Yoo Jeon Hwang-Bo In Sik Chung Jong-Hwa Park 《Biotechnology letters》2011,33(1):41-46
We established a bicistronic expression system using an encephalomyocarditis virus (EMCV)-derived internal ribosomal entry
site (IRES) element to generate stably transformed Drosophila
melanogaster Schneider 2 (S2) cells expressing human rotavirus Wa capsid proteins, VP2 and VP6, for the synthesis of VP2/6 double-layered
virus-like particle (DVLP). The EMCV-derived IRES permitted bicistronic translation of recombinant VP6. Recombinant VP2 and
VP6 were detected in extracellular fractions of stably transformed S2 cells. A wheel-like DVLP (diam ~ 50–55 nm) with short
spikes was produced from the extracellular fraction of stably transformed S2 cells. A bicistronic expression system using
an EMCV-derived IRES element can thus be used to express two proteins of interest in stably transformed S2 cells. The bi-or
tri-cistronic expression of recombinant VP2/6/7 using stably transformed S2 cells can also be used to produce rotavirus VLPs. 相似文献
977.
Efficient fermentation of xylose, which is abundant in hydrolysates of lignocellulosic biomass, is essential for producing
cellulosic biofuels economically. While heterologous expression of xylose isomerase in Saccharomyces cerevisiae has been proposed as a strategy to engineer this yeast for xylose fermentation, only a few xylose isomerase genes from fungi
and bacteria have been functionally expressed in S. cerevisiae. We cloned two bacterial xylose isomerase genes from anaerobic bacteria (Bacteroides stercoris HJ-15 and Bifidobacterium longum MG1) and introduced them into S. cerevisiae. While the transformant with xylA from B. longum could not assimilate xylose, the transformant with xylA from B. stercoris was able to grow on xylose. This result suggests that the xylose isomerase (BsXI) from B. stercoris is functionally expressed in S. cerevisiae. The engineered S. cerevisiae strain with BsXI consumed xylose and produced ethanol with a good yield (0.31 g/g) under anaerobic conditions. Interestingly, significant
amounts of xylitol (0.23 g xylitol/g xylose) were still accumulated during xylose fermentation even though the introduced
BsXI might not cause redox imbalance. We investigated the potential inhibitory effects of the accumulated xylitol on xylose fermentation.
Although xylitol inhibited in vitro BsXI activity significantly (K
I = 5.1 ± 1.15 mM), only small decreases (less than 10%) in xylose consumption and ethanol production rates were observed when
xylitol was added into the fermentation medium. These results suggest that xylitol accumulation does not inhibit xylose fermentation
by engineered S. cerevisiae expressing xylA as severely as it inhibits the xylose isomerase reaction in vitro. 相似文献
978.
Kim JH Kim K Youn BU Jin HM Kim JY Moon JB Ko A Seo SB Lee KY Kim N 《The Biochemical journal》2011,433(2):253-262
The MTM (myotubularin)/MTMR (myotubularin-related) protein family is comprised of 15 lipid phosphatases, of which nine members are catalytically active. MTMs are known to play a fundamental role in human physiology as gene mutations can give rise to X-linked myotubular myopathy or Charcot-Marie-Tooth disease, which manifest in skeletal muscle or in peripheral neurons respectively. Interestingly, studies have shown MTMR2 and MTMR5, two MTM family members, to be highly expressed in the testis, particularly in Sertoli and germ cells, and knockout of either gene resulted in spermatogenic defects. Other studies have shown that MTMR2 functions in endocytosis and membrane trafficking. In the testis, MTMR2 interacts and co-localizes with c-Src/phospho-Src-(Tyr?1?), a non-receptor protein tyrosine kinase that regulates the phosphorylation state of proteins at the apical ES (ectoplasmic specialization), a unique type of cell junction found between Sertoli cells and elongating/elongated spermatids. In the present review, we highlight recent findings that have made a significant impact on our understanding of this protein family in normal cell function and in disease, with the emphasis on the role of MTMs and MTMRs in spermatogenesis. We also describe a working model to explain how MTMR2 interacts with other proteins such as c-Src, dynamin 2, EPS8 (growth factor receptor pathway substrate 8) and ARP2/3 (actin-related protein 2/3) at the apical ES and the apical TBC (tubulobulbar complex; tubular-like invaginations that function in the disassembly of the apical ES and in the recycling of its components) to regulate spermiation at late stage VIII of the seminiferous epithelial cycle. 相似文献
979.
Past research has shown that aggressive behaviors can affect female reproductive outcome in nonhuman primate captive breeding programs. In this study, aggressive behaviors were recorded in a colony of pigtailed macaque monkeys (Macaca nemestrina) and related to pregnancy outcome. For 22 weeks, behavioral data were collected from nine breeding groups, consisting of zero to one male (some males were removed after a cycle of conceptions for husbandry reasons) and four to eight females. Observations included all occurrences of 11 aggressive behaviors during 15 min observation sessions, 1-3 times a week. Mean weekly aggression levels during the study period were determined for each group as well as for each pregnancy. Aggression data were summarized with Principal Components Analyses. Results indicate that pigtailed macaque aggression falls into five distinctive categories: warn, engage, threaten, pursue, and attack. Breeding groups differed in their levels of aggression, even after controlling for group size, presence of a sire, and group stability. Levels of the five aggression categories were found to affect the probability that a pregnancy ended in either a natural birth of a live infant, a clinical intervention producing a live infant, or a nonviable outcome. The predictive value of aggression was significant when clinical interventions were included as possible reproductive outcomes. Behavioral observation of captive groups could identify "risk" conditions affecting pregnancy outcome and the requirement for clinical intervention. 相似文献
980.
Lee CH Yoo KY Choi JH Park JH Kim DH Park JH Hwang IK Cho JH Kim YM Won MH 《Cellular and molecular neurobiology》2011,31(3):449-457
In this study, the authors examined the difference of phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) in
the hippocampal CA1 region (CA1) between adult and aged gerbils after 5 min of transient cerebral ischemia. Delayed neuronal
death in the CA1 of the aged group was much slower than that in the adult group after ischemia/reperfusion (I/R). pERK1/2
immunoreaction was observed in the CA1 region of the sham-operated adult gerbil. pERK1/2 immunoreactivity and protein levels
in the ischemic CA1 region of the adult group were markedly increased 4 days after I/R, and then reduced up to 10 days after
I/R. In contrast, pERK1/2 immunoreaction was hardly detected in the CA1 region of sham-operated aged gerbils, and the immunoreactivity
increased from 1 day after the ischemic insult, and still observed until 10 days post-ischemia. In addition, pERK1/2-immunoreaction
was expressed in astrocytes in the ischemic CA1 region: The expression in the ischemia-operated aged gerbils was later than
that in the ischemia-operated adult gerbils. These results indicate that different patterns of ERK1/2 immunoreactivity may
be associated with different processes of delayed neuronal death in adult and aged animals. 相似文献