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1.
Biomaterials ; 229: 119580, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31707296

RESUMO

Hypoxia, which frequently reduces the sensitivity to many therapeutic interventions, including chemotherapy, radiotherapy and phototherapy, has been acknowledged as an important reason for poor prognosis. Burgeoning evidences have proved that the tumor hypoxia microenvironment can reduce the therapeutic effect on tumor through inhibiting the drug efficacy, limiting immune cell infiltration of tumors and accelerating tumor recurrence and metastasis. However, the relationship between oxygen supply and the proliferation of cancer cells is still ambiguous and argued. Different from the current commonly used oxygen supply strategies, this study concentrated on the reduction of endogenous oxygen consumption. Specifically, a novel photosensitizers (IR780) and metformin are packaged in PEG-PCL liposomes. Once such nanoparticles accumulated in tumor tissues, the tumor foci were irradiated through 808 nm laser, generated ROS to further release metformin and IR780. Metformin can directly inhibit the activity of complex Ⅰ in the mitochondrial electron transport chain, thus performed a potent inhibitor of cell respiration. After overcoming tumor hypoxia, the combination of mitochondria-targeted photodynamic therapy (PDT) and photothermic therapy (PTT) via IR780 may achieve superior synergistically therapeutic efficacy. Benefit from excellent characteristics of IR780, such synergistic PDT PTT with the inhibition of mitochondrial respiration can be monitored through near-infrared/photoacoustic dual-modal imaging. Such a conception of reducing endogenous oxygen consumption may offer a novel way to solve the important puzzles of hypoxia-induced tumor resistance to therapeutic interventions, not limited to phototherapy.

2.
J Genet Genomics ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31776062

RESUMO

The functional heterogeneity of hematopoietic stem cells (HSCs) has been comprehensively investigated by single-cell transplantation assay. However, the heterogeneity regarding their physiological contribution remains an open question, especially for those with life-long hematopoietic fate of rigorous self-renewing and balanced differentiation capacities. In this study, we revealed that Procr expression was detected principally in phenotypical vascular endothelium co-expressing Dll4 and CD44 in the mid-gestation mouse embryos, and could enrich all the HSCs of the embryonic day 11.5 (E11.5) aorta-gonad-mesonephros (AGM) region. We then used a temporally restricted genetic tracing strategy to irreversibly label the Procr-expressing cells at E9.5. Interestingly, most labeled mature HSCs in multiple sites (such as AGM) around E11.5 were functionally categorized as lymphomyeloid-balanced HSCs assessed by direct transplantation. Furthermore, the labeled cells contributed to an average of 7.8% of immunophenotypically defined HSCs in E14.5 fetal liver (FL) and 6.9% of leukocytes in peripheral blood (PB) during one-year follow-up. Surprisingly, in aged mice of 24 months, the embryonically tagged cells displayed constant contribution to leukocytes with no bias to myeloid or lymphoid lineages. Altogether, we demonstrated, for the first time, the existence of a subtype of physiologically long-lived balanced HSCs as hypothesized, whose precise embryonic origin and molecular identity await further characterization.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31751198

RESUMO

A Gram-stain-positive, moderately halophilic, strictly aerobic, endospore-forming, rod-shaped bacterium, strain JSM 102062T, was isolated from a non-saline farm soil sample collected from Dehang Canyon in Hunan, PR China. Growth occurred with 0.5-20 % (w/v) NaCl (optimum 4-7 %) at pH 5.5-11.0 (optimum pH 8.0) and at 20-50 °C (optimum 30-35 °C). Contained cell-wall peptidoglycan based on meso-diaminopimelic acid and possessed menaquinone-7 (MK-7) as the major respiratory isoprenoid quinone. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The polar lipid pattern consisted of diphosphatidylglycerol, phosphatidylglycerol, five unidentified phospholipids and an unidentified glycolipid. The DNA G+C content was 44.1 mol%. Phylogeny based on 16S rRNA gene sequences indicated that strain JSM 102062T belonged to the genus Sediminibacillus, sharing high 16S rRNA gene sequence similarities to Sediminibacillus halophilus EN8dT (99.4 %) and Sediminibacillus albus NHBX5T (98.3 %). The whole genomic analysis showed that strain JSM 102062T constituted a different taxon separated from the recognized Sediminibacillus species. Combined data from phenotypic and genotypic studies demonstrated that strain JSM 102062T represents a noval species of the genus Sediminibacillus, for which the name Sediminibacillus terrae sp. nov. is proposed; the type strain is JSM 102062T (=CCTCC AB 2014166T = CGMCC 1.12957T=DSM 28949T=KCTC 33541T).

4.
J Anim Sci ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31740932

RESUMO

Enteric methane (CH4) emissions is not only an important source of greenhouse gases (GHG), but also a loss of dietary energy in livestock. Corn oil (CO) is rich in UFA with >50% polyunsaturated fatty acids, which may enhance ruminal biohydrogenation of unsaturated fatty acids, leading to changes in ruminal H2 metabolism and methanogenesis. The objective of this study was to investigate the effect of corn oil supplementation of a diet on CH4 emissions, nutrient digestibility, ruminal dissolved gases, fermentation and microbiota in goats. Six female goats were used in a crossover design with 2 dietary treatments, which included control and corn oil supplementation (30 g/kg dry matter basis). Corn oil supplementation did not alter total-tract organic matter digestibility or populations of predominant ruminal fibrolytic microorganisms (protozoa, fungi, Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes), but reduced enteric CH4 emissions (g/kg dry matter intake, -15.1%, P = 0.003). Corn oil supplementation decreased ruminal dissolved hydrogen (P < 0.001) and dissolved CH4 (P < 0.001) concentrations, proportions of total unsaturated fatty acids (P < 0.001) and propionate (P = 0.015), and increased proportions of total saturated fatty acids (P < 0.001) and acetate (P < 0.001), and acetate to propionate ratio (P = 0.038) in rumen fluid. Corn oil supplementation decreased relative abundance of family Bacteroidales_BS11_gut_group (P = 0.032), increased relative abundance of family Rikenellaceae (P = 0.021) and Lachnospiraceae (P = 0.025), and tended to increase relative abundance of genus Butyrivibrio_2 (P = 0.06). Relative abundance (P = 0.09) and 16S rRNA gene copies (P = 0.043) of order Methanomicrobiales, and relative abundance of genus Methanomicrobium (P = 0.09) also decreased with corn oil supplementation, but relative abundance (P = 0.012) and 16S rRNA gene copies (P = 0.08) of genus Methanobrevibacter increased. In summary, corn oil supplementation increased rumen biohydrogenatation by facilitating growth of biohydrogenating bacteria of family Lachnospiraceae and genus Butyrivibrio_2, and may have enhanced reductive acetogenesis by facilitating growth of family Lachnospiraceae. In conclusion, dietary supplementation of corn oil led to a shift of fermentation pathways that enhanced acetate production and decreased rumen dH2 concentration and CH4 emissions.

5.
Dis Markers ; 2019: 8410290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687049

RESUMO

Previous studies indicated that single-nucleotide polymorphisms (SNPs) of interferon gamma (IFNG) and IFNG receptor 1 (IFNGR1) may be involved in the pathogenesis of pulmonary tuberculosis (PTB) in different populations. In order to further explore the results in a Chinese Han population, this study was designed to investigate potential associations between the polymorphisms in IFNG and IFNGR1 and susceptibility to latent tuberculosis infection (LTBI) and/or PTB in a Chinese Han population. A total of 209 PTB, 173 LTBI, and 183 healthy control subjects (HCS) were enrolled in our study. Genotyping was conducted using an improved multiplex ligase detection reaction (iMLDR). We performed a logistic regression including sex and age as covariates to test the effect of alleles/genotypes on LTBI and/or TB. All six markers studied in IFNG and IFNGR1 conformed to the Hardy-Weinberg equilibrium (HWE). The IFNG rs1861494 was significantly associated with LTBI in recessive model, and the CC+CT genotype decreased risk of LTBI by 50% (P = 0.046, OR = 0.50, 95%CI: 0.25-0.99). The IFNGR1 rs2234711 was significantly associated with LTBI, and allele A increased the risk of LTBI by 55% (P = 0.047, OR = 1.55, 95%CI: 1.00-2.40). In the present study, we found that IFNG and IFNGR1 polymorphisms were associated with LTBI.

6.
Curr Top Med Chem ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31724506

RESUMO

Gynostemma pentaphyllum (Thunb.) Makino (GpM) and its derivatives, especially gypenosides (Gyps), are widely used as safe and convenient natural herbal drugs for the treatment of many diseases for a long time, and Gyps have different oral bioavailability (OB) values and low ability to cross blood-brain barrier (BBB). The effect of GpM and isolates on fibrosis, inflammation, oxidation, proliferation and migration are proved. GpM show bidirectional regulation effect on proliferation, oxidation and apoptosis in tumor and non-tumor cells. GpM and its extractions can resist proliferation, activate oxidation and apoptosis in tumor cells and have opposite effects in non-tumor cells. We succinctly present some current views of medicinal value and potential therapeutic mechanisms of GpM and its derivatives.

7.
J Agric Food Chem ; 67(46): 12816-12823, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31675231

RESUMO

Microbial degradation plays a major role in the dissipation of pendimethalin, and nitroreduction is an initial and detoxicating step. Previously, a pendimethalin nitroreductase, PNR, was identified in Bacillus subtilis Y3. Here, another pendimethalin nitroreductase from strain Y3, LNR, was identified. LNR shares only 40% identity with PNR and reduces the aromatic ring C-6 nitro group of pendimethalin and both nitro groups of trifluralin, butralin, and oryzalin. The catalytic activities against the four dinitroanilines were much higher for LNR than for PNR. lnr deletion significantly reduced the pendimethalin-reduction activity (60% activity loss), while pnr deletion led to only 30% activity loss, indicating that both LNR and PNR were involved in pendimethalin nitroreduction in strain Y3; however, LNR played the major role. This study facilitates the elucidation of pendimethalin catabolism and provides degrading enzyme resources for the removal of dinitroaniline herbicide residues in environment and agricultural products.

8.
Chin Med J (Engl) ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31764180

RESUMO

BACKGROUND: Lung transplantation (LT) has been demonstrated as the only effective therapy for patients with end-stage lung diseases. Increasing listed lung transplant candidates and expanding volumes of lung transplant centers across China require well-organized programs and registry data collection based on the large population. This study aimed to summarize and analyze the data of LT development in China. METHODS: We retrospectively collected and analyzed data from the China Lung Transplantation Registry (CLuTR). Key data were reported from the registry with transplant types, indications, donor and recipient characteristics, outcomes and survival. The survival <30 days, 1-year and 3-year survival rates were estimated with risk factors identified. RESULTS: CLuTR contained data from 1053 lung transplants performed through January 1st, 2015 to December 31st, 2018 reported by 18 registered transplant centers. The largest category of diagnosis before transplantation was idiopathic interstitial pneumonitis. The total <30 days, 1-year and 3-year survival rates in CLuTR were 81.45%, 70.11%, and 61.16% with discrepancy by indications. Large proportion of recipients who were more than 60 years old required higher standard of care. Infection-related complications resulted in more death events in the early post-surgery periods. New York Heart Association grading at listing, extra-corporeal membrane oxygenation usage peri-transplantation, allograft dysfunction (primary graft dysfunction >Grade 0), renal insufficiency (estimated glomerular filtration rate <60 mL·min·1.73 m), were independently associated with a higher risk for 3-year mortality in the entire cohort. CONCLUSIONS: Facing more end-stage of lung diseases and comorbidities, this study analyzed the outcomes and survival of LT recipients in China. Further prospectively stratified analyses with longer follow-up will be needed.

9.
BMC Pulm Med ; 19(1): 200, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694599

RESUMO

BACKGROUND: Tuberculous meningitis is the most devastating presentation of disease with Mycobacterium tuberculosis. We sought to evaluate treatment outcomes for adult patients with this disease. METHODS: The Ovid MEDLINE, EMBASE, Cochrane Library and Web of Science databases were searched to identify all relevant studies. We pooled appropriate data to estimate treatment outcomes at the end of treatment and follow-up. RESULTS: Among the articles identified, 22 met our inclusion criteria, with 2437 patients. In a pooled analysis, the risk of death was 24.7% (95%CI: 18.7-31.9). The risk of neurological sequelae among survivors was 50.9% (95%CI: 40.2-61.5). Patients diagnosed in stage III or human immunodeficiency virus (HIV) positive were significantly more likely to die (64.8, 53.4% respectively) during treatment. The frequency of cerebrospinal fluid (CSF) acid-fast-bacilli smear positivity was 10.0% (95% CI 5.5-17.6), 23.8% (15.2-35.3) for CSF culture positivity, and 22.3% (17.8-27.5) for CSF polymerase chain reaction positivity. We found that the headache, fever, vomiting, and abnormal chest radiograph were the most common symptoms and diagnostic findings among tuberculous meningitis patients. CONCLUSIONS: Despite anti-tuberculosis treatment, adult tuberculous meningitis has very poor outcomes. The mortality rate of patients diagnosed in stage III or HIV co-infection increased significantly during treatment.

10.
Mol Med Rep ; 20(5): 4665-4673, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31702032

RESUMO

Bone marrow­derived mesenchymal stem cells (BMSCs) possess potential therapeutic properties for treating patients with chronic obstructive pulmonary disease (COPD), which is characterized by emphysema and obstructive sleep apnea (OSA). However, their effects on overlap syndrome (OS) remain unclear. We investigated the potential therapeutic effects and possible mechanisms of BMSC transplantation in OS rats. To generate the OS model in rats, the animals underwent daily exposure to cigarette smoke and intermittent hypoxia. BMSCs were intravenously injected into rats. At 4 weeks post­transplantation, the severity of emphysema was assessed by lung hematoxylin and eosin (H&E) staining. The levels of oxidative stress and the malondialdehyde (MDA) and superoxide dismutase (SOD) contents in serum and lung were detected. The apoptosis of alveolar septal cells was also detected by TUNEL assay. Finally, we determined the expression of CD31 and VWF in lung tissues by an immunohistochemical (IHC) assay. It was found that BMSCs were able to migrate to the injured lung and aorta tissues. In lung tissues, transplanted BMSCs, some of which had differentiated into endotheliocytes, were found in the alveolar walls. The mean linear intercept (MLI) and pathological scores were higher and the mean alveolar number (MAN) was lower in the OS group than these parameters in the control group. These values were significantly reduced in the OS+BMSC group compared to those in the OS group. The MDA content was decreased and SOD activity was increased in the OS+BMSC group compared to those in the OS group. The apoptotic index of alveolar wall cells in the OS group was higher than that in the OS+BMSC group. The expression levels of CD31 and VWF in alveolar wall cells in the OS group were lower than those in the OS+BMSC group. These results indicate that BMSCs may inhibit the progression of emphysema in the OS model by differentiating into endotheliocytes and suppressing the apoptosis of endotheliocytes and oxidative stress. There is a possibility that the release of growth factors and structural support may be a determinant for the regenerative effects observed following treatment with BMSCs.

11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(5): 469-475, 2019 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-31721491

RESUMO

OBJECTIVE: This study aims to compare the osteogenic differentiation capability of stem cells derived from human inflammatory periodontal ligament tissues (iPDLSCs) with those of stem cells derived from healthy periodontal ligament tissues (hPDLSCs). Both types of tissues were induced by stromal cell derived factor (SDF-1) in vitro. METHODS: iPDLSCs and hPDLSCs were primarily cultured by tissue digestion method and purified by limited dilution cloning. The cells were passaged and identified by stem cell surface marker expression through flow cytometry. Then, we used thiazolyl blue tetrazolium bromide to detect and compare the proliferation capabilities of the iPDLSCs and hPDLSCs. Express of bone volumes were detected by alizarin red staining after SDF-1 was added to the cells. Using alkaline phosphatase, we evaluated the osteogenic differentiation capability of the cells induced by SDF-1. The expression levels of the osteogenesis-related genes of the cells induced by SDF-1 were determined by reverse transcription-polymerase chain reaction. RESULTS: After purification, both iPDLSCs and hPDLSCs expressed stem cell markers. hPDLCSs had a higher proliferation capability than iPDLSCs. Osteogenesis-related genes had higher expression levels in the cells induced by SDF-1 than in those without induction (P<0.05). SDF-1 at 50 and 200 ng·mL⁻¹ concentration greatly affected the differen-tiation capabilities of iPDLSCs and hPDLSCs respectively. CONCLUSIONS: iPDLSCs and hPDLSCs had osteogenic differentia-tion capability. The level of osteogenic differentiation in normal and inflamed periodontal ligament stem cells increases after SDF-1 induction.


Assuntos
Osteogênese , Ligamento Periodontal , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Células-Tronco , Células Estromais
12.
Pediatr Infect Dis J ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31725555

RESUMO

BACKGROUND: Evaluation of a pneumococcal conjugate vaccine (PCV) in an animal model provides an initial assessment of the performance of the vaccine prior to evaluation in humans. Cost, availability, study duration, cross-reactivity and applicability to humans are several factors which contribute to animal model selection. PCV15 is an investigational 15-valent PCV which includes capsular polysaccharides from pneumococcal serotypes (ST) 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F and 33F all individually conjugated to cross-reactive material 197 (CRM197). METHODS: Immunogenicity of PCV15 was evaluated in infant rhesus macaques (IRM), adult New Zealand white rabbits (NZWR) and CD1 mice using multiplexed pneumococcal electrochemiluminescent (Pn ECL) assay to measure serotype-specific IgG antibodies, multiplexed opsonophagocytosis assay (MOPA) to measure serotype-specific functional antibody responses and bacterial challenge in mice to evaluate protection against a lethal dose of S. pneumoniae. RESULTS: PCV15 was immunogenic and induced both IgG and functional antibodies to all 15 vaccine serotypes in all animal species evaluated. PCV15 also protected mice from S. pneumoniae serotype 14 intraperitoneal challenge. Opsonophagocytosis assay (OPA) titers measured from sera of human infants vaccinated with PCV15 in a Phase 2 clinical trial showed a good correlation with that observed in IRM (rs=0.69, P=0.006), a medium correlation with that of rabbits (rs=0.49, P=0.06), and no correlation with that of mice (rs=0.04, P=0.89). In contrast, there was no correlation in serum IgG levels between human infants and animal models. CONCLUSIONS: These results demonstrate that PCV15 is immunogenic across multiple animal species, with IRM and human infants showing the best correlation for OPA responses.

13.
Sleep Health ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31685441

RESUMO

OBJECTIVE: This study examined the prevalence, sociodemographic features, patterns of comorbidity, and impact on functional impairment of excessive sleepiness (Ex.S) and associated symptoms in a nationally representative sample of adults using the National Comorbidity Survey Replication (NCS-R) dataset. METHODS: Participants ≥18 years (n = 5,962) were queried about their sleep using the Composite International Diagnostic Interview (CIDI). Specifically, respondents were questioned about feeling sleepy during the day and falling asleep in permissive situations, feelings of insufficient sleep despite adequate time in bed, and/or difficulty waking up. Those endorsing daytime sleepiness and at least one additional symptom were considered to have Ex.S plus associated symptoms. Associations between Ex.S plus associated symptoms and sociodemographics, Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) mental disorders, chronic physical conditions, and functional impairment were examined. RESULTS: The prevalence of Ex.S plus associated symptoms in U.S. adults was 23.34% (standard error [SE] = 0.88) and significantly co-occurred with insomnia-related symptoms after adjusting for confounders (Odds ratio [OR] = 5.65; 95% confidence interval [CI] = 4.55-7.02). The presence of Ex.S and associated symptoms was more common in women, particularly younger women, those with lower family income, and the unemployed (all P<.001). After controlling for demographic characteristics and other confounders, Ex.S plus associated symptoms was associated with having a DSM-IV mental disorder (OR = 4.25; 95% CI = 3.53-5.10), a chronic physical condition (OR = 2.57; 95% CI = 1.94-3.42) and greater disability (P<.001). CONCLUSION: Ex. S with associated symptoms was common, frequently co-occurred with other mental and physical conditions, and was associated with substantial disability. Dissipation of some associations after controlling for insomnia-related symptoms indicated that physical-mental comorbidity and disability were greater among individuals with more pervasive sleep disturbances.

14.
Sci Rep ; 9(1): 15285, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653891

RESUMO

Two complete chloroplast genome sequences of Asteropyrum, as well as those of 25 other species from Ranunculaceae, were assembled using both Illumina and Sanger sequencing methods to address the structural variation of the cp genome and the controversial systematic position of the genus. Synteny and plastome structure were compared across the family. The cp genomes of the only two subspecies of Asteropyrum were found to be differentiated with marked sequence variation and different inverted repeat-single copy (IR-SC) borders. The plastomes of both subspecies contains 112 genes. However, the IR region of subspecies peltatum carries 27 genes, whereas that of subspecies cavaleriei has only 25 genes. Gene inversions, transpositions, and IR expansion-contraction were very commonly detected in Ranunculaceae. The plastome of Asteropyrum has the longest IR regions in the family, but has no gene inversions or transpositions. Non-coding regions of the cp genome were not ideal markers for inferring the generic relationships of the family, but they may be applied to interpret species relationship within the genus. Plastid phylogenomic analysis using complete cp genome with Bayesian method and partitioned modeling obtained a fully resolved phylogenetic framework for Ranunculaceae. Asteropyrum was detected to be sister to Caltha, and diverged early from subfamily Ranunculoideae.

15.
Biochem Cell Biol ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31626739

RESUMO

Long non-coding RNAs (lncRNAs) are emerging as vital regulators in various physiological and pathological processes. It was recently found that lncRNA HIF1A-AS2 could play oncogenic roles in several cancers. However, the function and regulatory mechanism of lncRNA HIF1A-AS2 in osteosarcoma (OS) remain largely unclear. In the present study, we demonstrated that HIF1A-AS2 was overexpressed in OS tissues and cells. HIF1A-AS2 downregulation could remarkably affect multiple OS cell biological functions, including cell proliferation, cell cycle progression, cell apoptosis, cell migration and cell invasion. Mechanistic investigations demonstrated that HIF1A-AS2 can interact with miR-33b-5p and negatively regulate its expression, thereby upregulate the protein expression of miR-33b-5p's target SIRT6. Additionally, in vivo experiments using a xenograft tumor mouse model revealed that HIF1A-AS2 downregulation suppressed tumor growth in OS. Taken together, a newly identified regulatory mechanism of lncRNA HIF1A-AS2/miR-33b-5p/SIRT6 axis was systematically studied in OS, which may hold promise as a promising target for treatment.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31617842

RESUMO

A novel Gram-stain-negative, curved rod-shaped, motile and non-endospore-forming strain, designated HX-2-15T, was isolated from activated sludge of agricultural chemical plant in Nanjing, Jiangsu province, PR China (32° 03' N, 118° 46' E) . Growth was observed at 15-37 °C (optimum between 25 and 30 °C), at pH 6.0-8.0 (optimum at pH 7.0) and with 0-3.0 % (w/v) NaCl (optimum at 0.5 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that the strain showed closest affiliation to Chitiniphilus shinanonensis SAY3T, with a sequence similarity of 99.0 %. The predominant cellular fatty acids were C16:0, C17:0 cyclo and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c). The major quinone was ubiquinone Q-8 . The polar lipid profile was composed of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, three unidentified phospholipids, one unidentified lipid and one unidentified aminophosphoglycolipid . The genomic DNA G+C content of the strain was 63.6 mol%. The ANI and dDDH values obtained between the genomes of HX-2-15T and C. shinanonensis SAY3T were 85.3 and 29.3 % respectively. On the basis of data from phenotypic, chemotaxonomic and genotypic analysis, strain HX-2-15T represents a novel species of the genus Chitiniphilus, for which the name Chitiniphilus eburneus sp. nov. is proposed. The type strain is HX-2-15T (=KCTC 72286T=CCTCC AB 2019178T).

17.
Immunity ; 51(5): 930-948.e6, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31604687

RESUMO

Generation of the first T lymphocytes in the human embryo involves the emergence, migration, and thymus seeding of lymphoid progenitors together with concomitant thymus organogenesis, which is the initial step to establish the entire adaptive immune system. However, the cellular and molecular programs regulating this process remain unclear. We constructed a single-cell transcriptional landscape of human early T lymphopoiesis by using cells from multiple hemogenic and hematopoietic sites spanning embryonic and fetal stages. Among heterogenous early thymic progenitors, one subtype shared common features with a subset of lymphoid progenitors in fetal liver that are known as thymus-seeding progenitors. Unbiased bioinformatics analysis identified a distinct type of pre-thymic lymphoid progenitors in the aorta-gonad-mesonephros (AGM) region. In parallel, we investigated thymic epithelial cell development and potential cell-cell interactions during thymus organogenesis. Together, our data provide insights into human early T lymphopoiesis that prospectively direct T lymphocyte regeneration, which might lead to development of clinical applications.

18.
Fish Shellfish Immunol ; 95: 328-335, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31655270

RESUMO

Mandarin fish (Siniperca chuatsi) is a significant cultured species with high added value in China. With the expansion of farming, diseases of mandarin fish such as Infectious spleen and kidney necrosis virus (ISKNV) diseases are becoming more and more serious. Human endogenous retrovirus subfamily H long terminal repeat associating protein 2 (HHLA2) is a type 1 transmembrane molecule with three extracellular Ig domains (IgV-IgC-IgV) and plays important roles in the T cell proliferation and tumorigenesis. The HHLA2-homologues have not been found in virus. In this study, a viral HHLA2 protein encoded by ISKNV ORF069L was identified and the virulence of the deleted ORF069L reconstruction ISKNV strain (ΔORF069L) was investigated. ISKNV ORF069L gene was predicted to encode a 222-amino acids peptide. The bioinformation analysis revealed that ISKNV ORF069L contained an Ig HHLA2 domain and was homologous to vertebrate B7-CD28 family proteins. The recombinant virus strain of ΔORF069L was constructed by homologous recombination technology. The virus titer and growth curves between ISKNV wild type (WT) and ΔORF069L on cellular level showed no significant differences indicating that the ORF069L did not influence the ISKNV replication. The expression levels of immune-related genes (Mx1, IL-1ß, IL-8, TNF-a and IgM) were increased in fish infected with ΔORF069L, compared to those in fish infected with ISKNV WT. Furthermore, the lethality caused by ΔORF069L declined by 40% compared with ISKNV WT, indicating that ORF069L was a virulence gene of ISKNV. Most importantly, the protection rate was nearly 100% for fish immunized with ΔORF069L strain. Those results suggested that ΔORF069L could be developed as a potential attenuated vaccine against ISKNV. Our work will be beneficial to promote the development of gene deletion attenuated vaccines for ISKNV disease.

19.
Org Lett ; 21(22): 8888-8892, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31592667

RESUMO

Asymmetric conjugate addition of aryl halides or aryl triflates to electron-deficient olefins was realized by sequential Miyaura borylation and Hayashi-Miyaura conjugate addition in one pot. A nickel-catalyzed borylation of aryl halides or triflates and a rhodium-chiral diene complex catalyzed enantioselective conjugate addition was executed as a pair of relay reactions as a more efficient and greener protocol.

20.
FEBS J ; 286(22): 4402-4417, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31618529

RESUMO

Crystallography has made a notable contribution to our knowledge of structural biology. For traditional crystallography experiments, the growth of crystals with large size and high quality is crucial, and it remains one of the bottlenecks. In recent years, the successful application of serial femtosecond crystallography (SFX) provides a new choice when only numerous microcrystals can be obtained. The intense pulsed radiation of X-ray free-electron lasers (XFELs) enables the data collection of small-sized crystals, making the size of crystals no longer a limiting factor. The ultrafast pulses of XFELs can achieve 'diffraction before destruction', which effectively avoids radiation damage and realizes diffraction near physiological temperatures. More recently, the SFX has been expanded to serial crystallography (SX) that can additionally employ synchrotron radiation as the light source. In addition to the traditional ones, these techniques provide complementary opportunities for structural determination. The development of SX experiments strongly relies on the advancement of hardware including the sample delivery system, the X-ray source, and the X-ray detector. Here, in this review, we categorize the existing sample delivery systems, summarize their progress, and propose their future prospectives.

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