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1.
Zhonghua Nei Ke Za Zhi ; 63(4): 401-405, 2024 Apr 01.
Artigo em Zh | MEDLINE | ID: mdl-38561286

RESUMO

This study aimed to explore the value of magnetic resonance imaging (MRI) T2 mapping in the assessment of dermatomyositis (DM) and polymyositis (PM). Thirty-three confirmed cases (myosin group) and eight healthy volunteers (healthy control group) at the Department of Rheumatology and Immunology, the First Affiliated Hospital of Kunming Medical University, from October 2016 to December 2017, were collected and analyzed. Multiple parameters of the myosin group were quantified, including creatine kinase (CK), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), complement C3, and complement C4. Disease status was evaluated using a panel of tools: myositis disease activity assessment tool-muscle (MDAAT-muscle), myositis disease activity assessment tool-whole (MDAAT-all), health assessment questionnaire (HAQ), medical outcomes study health survey short form-36 item (SF-36), hand muscle strength test (MMT-8) score, and MRI T2 mapping of muscle (22 muscles in the pelvis and thighs) T2 values. The results showed that in the myositis group, the measurements for CK, ESR, CRP, complement C3, and complement C4 were 457.2 (165.6, 1 229.2) IU/L, 20 (10, 42) mm/1h, 3.25 (2.38, 10.07) mg/L, 0.90 (0.83, 1.06) g/L, and 0.18 (0.14, 0.23) g/L, respectively. The scores for MMT-8, MDAAT-muscle, MDAAT-all, HAQ, and SF-36 were 57.12±16.23, 5.34 (4.00, 6.00), 34.63±12.62, 1.55 (0.66, 2.59), and 44.66±7.98, respectively. T2 values were significantly higher in all 22 muscles of the pelvis and thighs of patients with DM or PM compared with the healthy controls [(54.99±11.60)ms vs. (36.62±1.66)ms, P<0.001], with the most severe lesions in the satrorius, iliopsoas, piriformis, gluteus minimus, and gluteus medius muscles. The total muscle T2 value in the myositis group was positively correlated with CK, MDAAT-muscle, MDAAT-all, and HAQ (r=0.461, 0.506, 0.347, and 0.510, respectively, all P<0.05). There was a negative correlation between complement C4, SF-36, and MMT-8 scores (r=-0.424, -0.549, and -0.686, respectively, all P<0.05). Collectively, the findings from this study suggest that MRI T2 mapping can objectively reflect the disease status of DM and PM.


Assuntos
Dermatomiosite , Miosite , Polimiosite , Humanos , Dermatomiosite/diagnóstico por imagem , Complemento C3 , Polimiosite/diagnóstico por imagem , Polimiosite/patologia , Miosite/patologia , Proteína C-Reativa/metabolismo , Imageamento por Ressonância Magnética/métodos , Creatina Quinase , Complemento C4 , Miosinas
2.
Zhonghua Gan Zang Bing Za Zhi ; 31(12): 1290-1296, 2023 Dec 20.
Artigo em Zh | MEDLINE | ID: mdl-38253073

RESUMO

Objective: To explore the therapeutic efficacy and factors influencing the sequential combination of nucleos(t)ide analogues (NAs) with pegylated interferon alpha (Peg-IFN-α) in the treatment of patients with chronic hepatitis B (CHB). Methods: 144 CHB cases with NAs treatment for more than 1 year, HBV DNA < 20 IU/ml, hepatitis B surface antigen (HBsAg) quantification < 3 000 IU/ml, treated with a sequential combination of Peg-IFN-α treatment for 48 to 96 weeks, and followed up were selected from the Fifth Medical Center of the PLA General Hospital between May 2018 and May 2020. Intention-to-treat analysis was used to measure the HBsAg clearance rate at 96 weeks. The Kaplan-Meier method was used to compute the cumulative HBsAg clearance rate at 96 weeks. Univariate and multivariate logistic regression were used to analyze the factors influencing HBsAg clearance at 48 weeks of sequential combination therapy. Univariate and multifactorial COX proportional hazard models were used to analyze the factors influencing HBsAg clearance following 96 weeks of prolonged PEG-IFN-α treatment. The receiver operating characteristic curve was used to assess the predictive value of factors influencing HBsAg clearance. A Mann-Whitney U test was used to compare the measurement data between groups. The count data was compared using the χ(2) test between groups. Results: 41 (28.47%) cases achieved HBsAg clearance at 48 weeks of sequential combination therapy. The HBsAg clearance rate at 96 weeks was 40.28% (58/144) by intention-to-treat analysis. The Kaplan-Meier method computed that the cumulative HBsAg clearance rate at 96 weeks was 68.90%. Multivariate logistic regression analysis showed that HBsAg quantification at baseline (OR = 0.090, 95%CI: 0.034-0.240, P < 0.001) and a 24-week drop in HBsAg level (OR = 7.788, 95%CI: 3.408-17.798, P < 0.001) were independent predictors of HBsAg clearance in CHB patients treated sequentially in combination with NAs and Peg-IFN-α for 48 weeks. Receiver operating characteristic curve analysis showed that the baseline HBsAg quantification [area under the receiver operating characteristic curve (AUC), 0.911, 95% CI: 0.852-0.952)] and 24-week drop in HBsAg level (AUC = 0.881, 95%CI: 0.814-0.930) had equally good predictive value for 48-week HBsAg clearance, but there was no statistically significant difference between the two (Z = 0.638, P = 0.523). The value of the combination of baseline HBsAg quantification and 24-week drop in HBsAg level (AUC = 0.981, 95%CI: 0.941-0.997) was superior to that of single baseline HBsAg quantification (Z = 3.017, P = 0.003) and 24-week drop in HBsAg level (Z = 3.214, P = 0.001) in predicting HBsAg clearance rate at 48 weeks. Multivariate COX proportional hazards model analysis showed that HBsAg quantification at 48 weeks (HR = 0.364, 95%CI: 0.176-0.752, P = 0.006) was an independent predictor of HBsAg clearance with a prolonged course to 96 weeks of Peg-IFN-α treatment. Conclusion: The HBsAg clearance rate can be accurately predicted with baseline HBsAg quantification combined with a 24-week drop in HBsAg level in patients with CHB who are treated with a sequential combination of NAs and Peg-IFN-α therapy for 48 weeks. Prolonging the course of Peg-IFN-α treatment can enhance the HBsAg clearance rate's capability. An independent predictor of HBsAg clearance is HBsAg quantification at 48 weeks of sequential combination therapy with a prolonged course of 96 weeks of Peg-IFN-α treatment.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Humanos , Hepatite B Crônica/tratamento farmacológico , Terapia Combinada , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico
3.
Zhonghua Gan Zang Bing Za Zhi ; 29(7): 666-672, 2021 Jul 20.
Artigo em Zh | MEDLINE | ID: mdl-34371537

RESUMO

Objective: To observe the dynamic changes of serum RANTES during the treatment with nucleos(t)ide analogues combined with pegylated interferon alpha (peginterferon-α), and further analyze the predictive effect of RANTES on HBsAg clearance in patients with chronic hepatitis B. Methods: 98 cases of chronic hepatitis B with quantitative HBsAg < 3 000 IU/ml and HBV DNA < 20 IU/ml after≥1 year NAs treatment were enrolled. Among them, 26 cases continued to receive NAs monotherapy, 72 cases received NAs combined with pegylated interferon alpha therapy. The changes in RANTES during treatment were observed. The receiver operating characteristic curve was used to analyze the early changes of RANTES to predict the HBsAg clearance during 48 weeks. Results: During 48 weeks, 15 cases (20.83%) had achieved HBsAg clearance in combination group, while no patient had achieved HBsAg clearance in NAs group. The overall serum RANTES level had decreased from baseline in NAs and combination group. At week 48, in the combination group, the serum RANTES level was decreased more significantly in patients with HBsAg clearance than patients without. Further analysis showed that, in combination group, HBsAg clearance rate of patients with serum RANTES decreased at week 12 and 24 was higher than patients with elevated (29.17% vs. 4.17%, P = 0.014; 28.00% vs. 4.55%, P = 0.052), and quantitative HBsAg reduction was larger significantly [(1.49 ± 1.26) log(10)IU/ml vs. (0.73 ± 0.81) log(10)IU/ml, P = 0.017; (1.54 ± 1.27) log(10)IU/ml vs. (0.57 ± 0.56) log(10)IU/ml, P = 0.004]. Receiver operating characteristic curve analysis showed that the baseline quantitative HBsAg and the reduction in quantitative HBsAg and serum RANTES during the early period were predictors of HBsAg clearance after 48-week combination therapy. Furthermore, the combination of baseline quantitative HBsAg and 12 - or 24-week reduction of serum RANTES were better predictors of HBsAg clearance than that of baseline quantitative HBsAg combined with HBsAg decrease at week 12 or 24. The area under the receiver operating characteristic curve of the former was 0.925 and 0.939, while that of the latter was 0.909 and 0.929, respectively. Conclusion: Early reduction of serum RANTES at week 12 and 24 can predict HBsAg loss in CHB patients receiving addition of peginterferon-α to ongoing NAs Therapy, so serum RANTES could be one of the key immunological markers for predicting HBsAg clearance.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Antivirais/uso terapêutico , Quimiocina CCL5/uso terapêutico , DNA Viral , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Resultado do Tratamento
4.
Zhonghua Gan Zang Bing Za Zhi ; 26(12): 927-932, 2018 Dec 20.
Artigo em Zh | MEDLINE | ID: mdl-30669786

RESUMO

Objective: To recognize the efficacy and safety of paritaprevir/ritonavir-ombitasvir combined with dasabuvir (OBV/PTV/RTV+DSV) in the treatment of genotype 1b chronic hepatitis C. Methods: Patients with genotype 1b chronic hepatitis C who were admitted to the People's Hospital of Henan Province, Huashan Hospital of Shanghai and the Fifth Medical Center of the General Hospital of the People's Liberation Army of China between November 2017 to August 2018 were enlisted. All patients received OBV/PTV/RTV+DSV antiviral therapy. HCV RNA levels were measured at baseline, weeks 1, 2, 3, 4, 8, 12, and 24, then 12 weeks, and 24 weeks after completion of treatment; patients' comorbidity, concomitant medications, and clinical adverse events were recorded. Results: 108 patients were enrolled in the study, with an average age of 49.1 years, 44 patients were male (40.8%), 96.3% (104/108) were newly diagnosed, and four patients had previous treatment history, of whom three were treated with IFN and one with IFN + DAA. Ninety-eight cases completed 12 weeks treatment and 89 cases were in follow up for 12 weeks, after discontinuation of the drug. Overall, 89 cases (100%) achieved SVR12.One patient treated with PR and DAA had HCV RNA level of 869175 IU/mL at 4 weeks of treatment, which was significantly higher than the baseline HCV RNA level (301776IU/ML), and was judged as failure of treatment; and follow-up was discontinued. Of all enrolled patients, 19 (17.6%) had underlying diseases and 15 (13.9%) had combined medications. During treatment, adverse events (AE) occurred in 11 patients (10.1%). The main adverse events were pruritus and elevated bilirubin. Conclusion: Combined antiviral therapy (OBV/PTV/RTV+DSV) of 12 weeks are highly effective with good safety profile in the treatment of Chinese patients with genotype 1b chronic hepatitis C.


Assuntos
Antivirais/efeitos adversos , Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Ritonavir , 2-Naftilamina , Anilidas , Carbamatos , China , Ciclopropanos , Quimioterapia Combinada , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Lactamas Macrocíclicas , Compostos Macrocíclicos , Masculino , Pessoa de Meia-Idade , Prolina/análogos & derivados , Ribavirina , Sulfonamidas , Resultado do Tratamento , Uracila/análogos & derivados , Valina
5.
J Viral Hepat ; 23(10): 755-66, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27004559

RESUMO

Host innate and adaptive immune responses must be tightly regulated by an intricate balance between positive and negative signals to ensure their appropriate onset and termination while fighting pathogens and avoiding autoimmunity; persistent pathogens may usurp these regulatory machineries to dampen host immune responses for their persistence in vivo. Here, we demonstrate that miR146a is up-regulated in monocytes from hepatitis C virus (HCV)-infected individuals compared to control subjects. Interestingly, miR146a expression in monocytes without HCV infection increased, whereas its level in monocytes with HCV infection decreased, following Toll-like receptor (TLR) stimulation. This miR146a induction by HCV infection and differential response to TLR stimulation were recapitulated in vitro in monocytes co-cultured with hepatocytes with or without HCV infection. Importantly, inhibition of miR146a in monocytes from HCV-infected patients led to a decrease in IL-23, IL-10 and TGF-ß expressions through the induction of suppressor of cytokine signalling 1 (SOCS1) and the inhibition of signal transducer and activator transcription 3 (STAT3), and this subsequently resulted in a decrease in regulatory T cells (Tregs) accumulated during HCV infection. These results suggest that miR146a may regulate SOCS1/STAT3 and cytokine signalling in monocytes, directing T-cell differentiation and balancing immune clearance and immune injury during chronic viral infection.


Assuntos
Citocinas/biossíntese , Hepacivirus/fisiologia , MicroRNAs/metabolismo , Monócitos/imunologia , Fator de Transcrição STAT3/biossíntese , Proteína 1 Supressora da Sinalização de Citocina/biossíntese , Linfócitos T Reguladores/imunologia , Regulação da Expressão Gênica , Hepacivirus/imunologia , Humanos , Tolerância Imunológica
8.
Proc Natl Acad Sci U S A ; 109(18): E1055-62, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22509004

RESUMO

Ge-Sb-Te-based phase-change memory is one of the most promising candidates to succeed the current flash memories. The application of phase-change materials for data storage and memory devices takes advantage of the fast phase transition (on the order of nanoseconds) and the large property contrasts (e.g., several orders of magnitude difference in electrical resistivity) between the amorphous and the crystalline states. Despite the importance of Ge-Sb-Te alloys and the intense research they have received, the possible phases in the temperature-pressure diagram, as well as the corresponding structure-property correlations, remain to be systematically explored. In this study, by subjecting the amorphous Ge(2)Sb(2)Te(5) (a-GST) to hydrostatic-like pressure (P), the thermodynamic variable alternative to temperature, we are able to tune its electrical resistivity by several orders of magnitude, similar to the resistivity contrast corresponding to the usually investigated amorphous-to-crystalline (a-GST to rock-salt GST) transition used in current phase-change memories. In particular, the electrical resistivity drops precipitously in the P = 0 to 8 GPa regime. A prominent structural signature representing the underlying evolution in atomic arrangements and bonding in this pressure regime, as revealed by the ab initio molecular dynamics simulations, is the reduction of low-electron-density regions, which contributes to the narrowing of band gap and delocalization of trapped electrons. At P > 8 GPa, we have observed major changes of the average local structures (bond angle and coordination numbers), gradually transforming the a-GST into a high-density, metallic-like state. This high-pressure glass is characterized by local motifs that bear similarities to the body-centered-cubic GST (bcc-GST) it eventually crystallizes into at 28 GPa, and hence represents a bcc-type polyamorph of a-GST.

9.
J Chem Phys ; 140(6): 064501, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24527926

RESUMO

Using molecular dynamics simulations, we investigate the temperature-dependent evolution of the first peak position/shape in pair distribution functions of liquids. For metallic liquids, the peak skews towards the left (shorter distance side) with increasing temperature, similar to the previously reported anomalous peak shift. Making use of constant-volume simulations in the absence of thermal expansion and change in inherent structure, we demonstrate that the apparent shift of the peak maximum can be a result of the asymmetric shape of the peak, as the asymmetry increases with temperature-induced spreading of neighboring atoms to shorter and longer distances due to the anharmonic nature of the interatomic interaction potential. These findings shed light on the first-shell expansion/contraction paradox for metallic liquids, aside from possible changes in local topological or chemical short-range ordering. The melts of covalent materials are found to exhibit an opposite trend of peak shift, which is attributed to an effect of the directionality of the interatomic bonds.

11.
Nat Commun ; 15(1): 3911, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724541

RESUMO

Vibrational spectroscopy allows us to understand complex physical and chemical interactions of molecular crystals and liquids such as ammonia, which has recently emerged as a strong hydrogen fuel candidate to support a sustainable society. We report inelastic neutron scattering measurement of vibrational properties of ammonia along the solid-to-liquid phase transition with high enough resolution for direct comparisons to ab-initio simulations. Theoretical analysis reveals the essential role of nuclear quantum effects (NQEs) for correctly describing the intermolecular spectrum as well as high energy intramolecular N-H stretching modes. This is achieved by training neural network models using ab-initio path-integral molecular dynamics (PIMD) simulations, thereby encompassing large spatiotemporal trajectories required to resolve low energy dynamics while retaining NQEs. Our results not only establish the role of NQEs in ammonia but also provide general computational frameworks to study complex molecular systems with NQEs.

12.
Phys Rev Lett ; 110(12): 125503, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-25166820

RESUMO

We report the first experimental observation of a liquid-liquid phase transition in the monatomic liquid metal cerium, by means of in situ high-pressure high-temperature x-ray diffraction experiments. At 13 GPa, upon increasing temperature from 1550 to 1900 K high-density liquid transforms to a low-density liquid, with a density difference of 14%. Theoretic models based on ab initio calculations are built to investigate the observed phase behavior of the liquids at various pressures. The results suggest that the transition primarily originates from the delocalization of f electrons and is deemed to be of the first order that terminates at a critical point.

13.
Lupus ; 22(10): 1001-10, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23893825

RESUMO

A higher prevalence of depression in systemic lupus erythematosus (SLE) patients has been reported, though the mechanism underlying this phenomenon remains unclear. The present study was conducted to explore whether the polymorphism and methylation status of the serotonin transporter gene (5HTT) promoter region (PR-5HTT) contribute to depression in SLE patients from both genetic and epigenetic perspectives. In this study, 96 SLE patients and 96 healthy controls (HCs) were recruited. Depression levels of all subjects were evaluated using the Hamilton Depression Rating Scale (HDRS). The serotonin transporter-linked polymorphism (5HTTLPR) and the DNA methylation status of PR-5HTT were detected in peripheral lymphocytes of SLE patients and HCs. The differences in 5HTTLPR and DNA methylation of PR-5HTT between SLEs and HCs were compared. In SLE patients, the frequencies of short allele (S) and SS genotype of 5HTTLPR were higher in depressive SLE (SLE-D) patients than in non-depressive SLE (SLE-ND) patients. The mean HDRS score of SS homozygote patients was higher than that of patients with SL/LL genotypes. Conversely, PR-5HTT was hypomethylated in HCs as well as SLE patients. There was no difference in the methylation status between HCs and SLEs. Thus, the functional expression of PR-5HTT may be primarily regulated by gene polymorphism and not by DNA methylation. The risk allele of 5HTTLPR appears to be a major contributor to depression in SLE patients.


Assuntos
Metilação de DNA , Depressão/genética , Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adulto , Sequência de Bases , Ilhas de CpG , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Feminino , Genótipo , Humanos , Masculino , Dados de Sequência Molecular
14.
Genet Mol Res ; 12(3): 3750-4, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-24085436

RESUMO

Paulownia kawakamii is a fast-growing timber tree. In this study, 21 primer sets were developed using an enriched genomic library. The genetic diversity was measured in one P. kawakamii population. The number of alleles per locus ranged from 2 to 19. The observed and expected heterozygosities varied from 0.158 to 0.842 (mean = 0.421) and from 0.376 to 0.952 (mean = 0.771), respectively. All 21 loci were also polymorphic in closely related species (P. tomentosa, P. elongata, and P. fortunei). The described markers will be useful in future population genetic studies and molecular breeding of these Paulownia species.


Assuntos
Repetições de Microssatélites , Scrophulariaceae/classificação , Scrophulariaceae/genética , Alelos , Primers do DNA/genética , Loci Gênicos , Variação Genética , Biblioteca Genômica , Heterozigoto , Especificidade da Espécie
15.
Plant Dis ; 97(1): 150, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30722285

RESUMO

Grapevine leafroll disease (GLD) is one of the most economically important diseases of cultivated grapevines (Vitis vinifera), causing decrease in yield, as well as decreasing the sugar levels and increasing the acidity of the berries (1). There are currently at least 10 serologically distinct viruses, referred to as grapevine leafroll-associated viruses (GLRaVs), from the family Closteroviridae that are associated with leafroll disease (4). China is one of the world's leading grape producers, and nearly 75% of the vineyards in China are located in Xinjiang Uygur Autonomous Region, and Hebei, Shandong, Gansu, Ningxia, and Yunnan provinces. Grapevine leafroll-associated virus 7 (GLRaV-7) isolates have been reported so far in Liaoning (GQ849392, GQ849393, and JF927943) and Henan (EF093187) provinces in China (3). The four Chinese isolates were isolated respectively from grape varieties, Cabernet Sauvignon (GQ849392, GQ849393), Centennial Seedless (JF927943), and Semillon (EF093187), and these grape varieties are introduced from abroad. Cow's Nipple and Dragon's Eye are old grape varieties native to China. Cow's nipple is extensively cultivated in Xinjiang Uygur Autonomous Region, while Dragon's Eye is widely planted in Heibei Province. To determine if GLRaV-7 was present in these two varieties, six samples (three per variety) were collected from six individual grapevines showing GLD-like symptoms in two vineyards in Xinjiang Uygur Autonomous Region and Hebei Province, respectively, in September 2011. Total RNA extracts obtained from phloem scrapings of samples using the RNeasy plant mini kit (QIAGEN) were tested by reverse transcription (RT)-PCR with primers F1 (5'-TATATCCCAACGGAGATGGC-3') and R1 (5'-ATGTTCCTCCACCAAAATCG-3') (2) specific to the heat shock protein 70 homologue (HSP-70 gene) of GLRaV-7. All samples produced a single band of the expected size of 502 bp. One GLRaV-7-specific amplicon per variety was cloned into pMD 18-T simple vector (TaKaRa). Plasmid DNA was purified using Column Plasmid DNAOUT (TIANDZ, Beijing, China) from three individual clones and sequenced from both directions. The sequence of the two isolates (GenBank Accession Nos. JX494722 and JX494723) shared 97.81% identity at the nucleotide level and 100% identity at the amino acid level. A pairwise comparison of HSP-70 sequences of the two isolates from this report with nine corresponding sequences of GLRaV-7 isolates (including four previously reported Chinese isolates) showed nucleotide sequence identities ranging from 91.24% (EF093187) to 98.80% (GQ849392). These samples were further analyzed by double antibody sandwich (DAS)-ELISA using antibody specific to GLRaV-7 (NEOGEN Europe, Ayr, Scotland) according to the manufacturer's instructions, and the results confirmed the presence of the virus in these samples that were positive by RT-PCR. To our knowledge, this is the first report of GLRaV-7 occurring in native grape varieties in China. These results could be helpful in developing sound diagnostic systems for implementing efficient disease management strategies. References: (1) B. Akbas et al. Hort. Sci. 36:97, 2009. (2) E. Engel et al. Plant Dis. 92:1252, 2008. (3) X. Fan et al. Acta Hortic. Sinica 39:949, 2012. (4) G. P. Martelli. Extended Abstr. 16th Meet. International Council for the Study of Virus and Virus-like Diseases of Grapevines (ICVG). 15-23, 2009.

16.
Plant Dis ; 97(10): 1339-1345, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30722147

RESUMO

To characterize the prevalence of viruses associated with grapevine leafroll disease in China, 249 grapevine (Vitis spp.) samples (86 popular cultivars and a rootstock) from 19 provinces and regions were collected and tested for Grapevine leafroll-associated virus 1 (GLRaV-1), GLRaV-2, GLRaV-3, GLRaV-4, and GLRaV-4 strain 5 by SYBR Green real-time reverse-transcription polymerase chain reaction (RT-PCR), and RT-PCR and sequencing. GLRaV-3 was found in 100% of the samples while GLRaV-1, GLRaV-2, and GLRaV-4 were detected in 24.9% (62/249), 15.3% (38/249), and 0.80% (2/249) of the samples, respectively. Single infections with GLRaV-3 were found in 66.3% (165/249) of the samples, and the remaining samples were mixed infections of GLRaV-3 with one or two other GLRaVs, those with GLRaV-1 being the most common (18.5%, 46/249). The genetic variability of Chinese GLRaV-3 isolates was characterized based on the coat protein (CP) gene. In total, 153 full-length CP gene sequences (94 sequences newly generated) of Chinese GLRaV-3 isolates from different grapevine-growing regions showed 89.3 to 100.0% and 92.7 to 100.0% identity at the nucleotide and amino acid levels, respectively. The average nucleotide diversity for the population of Chinese GLRaV-3 isolates was estimated at 0.037 (standard error = 0.0032). GLRaV-3 isolates from China segregated into five distinct phylogenetic groups and two novel recombination events were found in the viral population. This is the first and most extensive report of the prevalent species of GLRaV in China, which also provides an assessment of genetic variability of GLRaV-3 Chinese isolates.

17.
Eur Rev Med Pharmacol Sci ; 27(12): 5397-5409, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37401274

RESUMO

OBJECTIVE: Adult stem cell senescence and exhaustion are important drivers of organismal age. Restored stem cell self-renewal has revealed novel therapeutic targets for decreasing the incidence of age-associated diseases (AADs) and prolonging the human health span. Transient ectopic expression of the reprogramming factors Oct3/4, Sox2, Klf4 and c-Myc (collectively known as OSKM) in somatic cells can induce partial cellular reprogramming and effectively ameliorate their age-associated hallmarks. However, how this form of rejuvenation is applied to senescent stem cells remains unknown. MATERIALS AND METHODS: The Integrin-α6highCD71high epidermal stem cells (ESCs) with low self-renewal ability were sorted by flow cytometry and then treated by the interrupted reprogramming induced by transient expression of OSKM. The ability of secondary clones' generation and self-proliferation in vitro, as well as stem cell marker p63, were detected to determine their self-renewal ability. Besides, gene and protein of epidermal cell markers were detected to determine whether their cell identities were retained. Finally, DNA methylation age (eAge) and DNA dehydroxymethylase/methyltransferase were analyzed to explore the alternation of their global DNA methylation pattern during this rejuvenation. RESULTS: The partial reprogramming restored the youthful self-renewal and proliferation in senescent ESCs, including larger secondary clone generation, higher expression of stem cell marker p63 and proliferation marker Ki67, and faster proliferation speed, in each case without abolishing epithelial cellular identity. Moreover, the rejuvenation of adult stem cells could be maintained for 2 weeks after reprogramming factor withdrawal, which was more stable than that of differentiated somatic cells. Additionally, we found that partial reprogramming counteracted the acceleration of eAge in senescent epidermal stem cells and DNA methyltransferase 1 (DNMT1) may play a crucial role in this process. CONCLUSIONS: Partial reprogramming has high therapeutic potential for reversing adult stem cell age, providing an advanced way to treat AADs.


Assuntos
Reprogramação Celular , Células-Tronco Pluripotentes Induzidas , Adulto , Humanos , Células-Tronco , Células Epidérmicas , Metiltransferases/metabolismo , DNA/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo
18.
J Chem Phys ; 137(4): 044501, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22852625

RESUMO

Atomic structures were obtained in equilibrium and supercooled eutectic Zr(75.5)Pd(24.5) liquids by in situ high-energy synchrotron diffraction measurements using the beamline electrostatic levitation (BESL) technique, which provides a high-vacuum, containerless, environment. Reverse Monte Carlo fits to the x-ray static structure factors, constrained using partial pair correlation functions obtained from ab initio molecular dynamics simulations, indicate the presence of medium-range order (MRO) in the form of a strong tendency for Pd-Pd (solute-solute) avoidance. This order persists over the entire temperature range studied, from 170 °C above the equilibrium liquidus temperature to 263 °C below it. Further, a quantitative analysis of the atomic structures obtained indicates a modest degree of icosahedral-like local order around Pd atoms, with the clusters showing an increased tendency for face-sharing to form more extended structures with decreasing temperature.

19.
Poult Sci ; 91(10): 2475-81, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22991530

RESUMO

Toll-like receptor 3 (TLR3) is an important membrane-bound receptor for recognizing double-stranded RNA in innate immunity. In this study, we described the cloning and characterization of the Muscovy duck TLR3 (MdTLR3) gene. The full-length MdTLR3 cDNA (2,836 bp) encoded a polypeptide of 895 amino acids. The deduced amino acid sequence contained 4 main structural domains: a signal peptide, an extracellular leucine rich repeats domain, a transmembrane domain, and a Toll/IL-1 receptor domain. Quantitative real-time PCR analysis indicated that MdTLR3 mRNA was constitutively expressed in all sampled tissues of uninfected Muscovy duck except muscle. Expression of MdTLR3 in brain was significantly upregulated at 24 h (1.94-fold, P < 0.05), reached a peak at 48 h (4.64-fold, P < 0.05), and recovered to normal levels at 72 h postinfection with the H5N1 highly pathogenic avian influenza virus. In contrast, MdTLR3 expression was downregulated during the test period in spleen and lung. These results implicated MdTLR3 was a novel member of the TLR family, which is involved in the early stage of antiviral innate immunity.


Assuntos
Clonagem Molecular , Patos/metabolismo , Regulação da Expressão Gênica/fisiologia , Receptor 3 Toll-Like/metabolismo , Sequência de Aminoácidos , Animais , Patos/genética , Virus da Influenza A Subtipo H5N1 , Influenza Aviária/metabolismo , Influenza Aviária/virologia , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor 3 Toll-Like/genética
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