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1.
Neurol Sci ; 45(6): 2719-2728, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38150131

RESUMO

OBJECTIVES: Patients with severe stroke are at high risk of developing acute respiratory distress syndrome (ARDS), but this severe complication was often under-diagnosed and rarely explored in stroke patients. We aimed to investigate the prevalence, early predictors, and outcomes of ARDS in severe stroke. METHODS: This prospective study included consecutive patients admitted to neurological intensive care unit (neuro-ICU) with severe stroke, including acute ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. The incidence of ARDS was examined, and baseline characteristics and severity scores on admission were investigated as potential early predictors for ARDS. The in-hospital mortality, length of neuro-ICU stay, the total cost in neuro-ICU, and neurological functions at 90 days were explored. RESULTS: Of 140 patients included, 35 (25.0%) developed ARDS. Over 90% of ARDS cases occurred within 1 week of admission. Procalcitonin (OR 1.310 95% CI 1.005-1.707, P = 0.046) and PaO2/FiO2 on admission (OR 0.986, 95% CI 0.979-0.993, P < 0.001) were independently associated with ARDS, and high brain natriuretic peptide (OR 0.994, 95% CI 0.989-0.998, P = 0.003) was a red flag biomarker warning that the respiratory symptoms may be caused by cardiac failure rather than ARDS. ARDS patients had longer stays and higher expenses in neuro-ICU. Among patients with ARDS, 25 (62.5%) were moderate or severe ARDS. All the patients with moderate to severe ARDS had an unfavorable outcome at 90 days. CONCLUSIONS: ARDS is common in patients with severe stroke, with most cases occurring in the first week of admission. Procalcitonin and PaO2/FiO2 on admission are early predictors of ARDS. ARDS worsens both short-term and long-term outcomes. The conflict in respiratory support strategies between ARDS and severe stroke needs to be further studied.


Assuntos
Síndrome do Desconforto Respiratório , Acidente Vascular Cerebral , Humanos , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/complicações , Masculino , Feminino , Idoso , Estudos Prospectivos , Prevalência , Pessoa de Meia-Idade , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/complicações , Unidades de Terapia Intensiva/estatística & dados numéricos , Índice de Gravidade de Doença , Mortalidade Hospitalar , Idoso de 80 Anos ou mais , Tempo de Internação/estatística & dados numéricos
2.
Mol Biol Rep ; 47(4): 3041-3047, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32193770

RESUMO

The lily-of-the-valley Convallaria (Asparagaceae) consists of three herbaceous perennial species. The plants are commonly found in northern hemisphere, and are best-known for their ornamental and pharmaceutical value. In order to assess the genetic structure, diversity and demographic history of Convallaria species, 19 novel microsatellite markers were developed based on transcriptome data of C. keiskei. Polymorphism and cross-amplification of the markers were tested in three populations of C. keiskei and one population each of C. majalis and C. montana. The transferability rate in two species was both 89.5%. The average number of alleles detected per locus was 7.7, 3.3 and 2.7 in C. keiskei, C. majalis and C. montana, respectively, and the polymorphism information content correspondingly varied from 0.067 to 0.730, from 0.071 to 0.637 and from 0.195 to 0.680 at the population level. The observed and expected heterozygosity ranged from 0.000 to 1.000 and from 0.000 to 0.833, respectively. Seven of the 19 loci showed significant deviation from Hardy-Weinberg equilibrium. The availability of these markers will provide a useful molecular tool for further population genetics, phylogeographic and breeding studies of Convallaria species.


Assuntos
Convallaria/genética , Repetições de Microssatélites/genética , Alelos , Asparagaceae/genética , Loci Gênicos/genética , Variação Genética/genética , Genética Populacional/métodos , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Polimorfismo Genético/genética , Transcriptoma/genética , Sequenciamento do Exoma/métodos
3.
Curr Microbiol ; 76(1): 7-14, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30310969

RESUMO

Copper mining caused severe damage to the ecological environment of mining areas. The combination of microbe and plant remediation has an application potential in improving the absorption and transformation efficiency of heavy metals. The phyllosphere is the largest biointerface on the planet, and bacteria are the dominant microbial inhabitants of the phyllosphere, believed to be critical to plant growth and health. This study investigated the phyllospheric and soil bacteria communities using high-throughput sequencing, and endophyte infection statuses of four natural grasses by toluidine blue heparin assay. Results showed variation in phyllospheric bacterial community structure. Gammaproteobacteria were the most abundant bacterial population. Bacilli were found in the phyllosphere of Bothriochloa ischaemum and Imperata cylindrica, while Clostridia were only found in Calamagrostis epigejos. Alphaproteobacteria were the dominant bacteria in soil. In addition, bacterial communities were influenced by endophytic infection statuses. Oxalobacteraceae was associated with soil carbon and sulfur. Enterobacteriaceae had negative correlation with the ratio of soil carbon and nitrogen, and had positive correlation with Cd content. These results offer useful insights into phyllospheric bacterial community variance in four different natural grasses in a copper tailings dam.


Assuntos
Alphaproteobacteria/isolamento & purificação , Bacillus/isolamento & purificação , Clostridiaceae/isolamento & purificação , Cobre/análise , Enterobacteriaceae/isolamento & purificação , Gammaproteobacteria/isolamento & purificação , Oxalobacteraceae/isolamento & purificação , Poaceae/microbiologia , Alphaproteobacteria/classificação , Alphaproteobacteria/genética , Bacillus/classificação , Bacillus/genética , Clostridiaceae/classificação , Clostridiaceae/genética , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Sequenciamento de Nucleotídeos em Larga Escala , Mineração , Oxalobacteraceae/classificação , Oxalobacteraceae/genética , RNA Ribossômico 16S/genética , Solo/química , Microbiologia do Solo
4.
Mol Cell ; 35(4): 534-41, 2009 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-19716796

RESUMO

The molecular pathways leading from genomic instability to cellular senescence and/or cell death remain incompletely characterized. Using mouse embryonic fibroblasts with constitutively increased DNA damage due to the absence of the full-length form of the tumor suppressor Brca1 (Brca1(Delta 11/Delta 11)), we show that deletion of p53 binding protein 1 (53BP1) selectivity abrogates senescence and cell death stimulated by reduced Brca1 activity. Furthermore, the embryonic lethality induced by Brca1 mutation can be alleviated by 53BP1 deletion. Adult Brca1(Delta 11/Delta 11)53BP1(-/-) manifest constitutively high levels of genomic instability, yet age relatively normally, with a surprisingly low incidence of overall tumor formation. Together, these in vitro and in vivo data suggest that 53BP1 is specifically required for the development of premature senescence and apoptosis induced by Brca1 deficiency. These observations may have important implications for Brca1-mediated tumor formation as well as for the molecular pathway leading from genomic instability to organismal aging.


Assuntos
Envelhecimento/genética , Proteína BRCA1/deficiência , Senescência Celular/genética , Instabilidade Genômica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Envelhecimento/metabolismo , Animais , Apoptose/genética , Proteínas Mutadas de Ataxia Telangiectasia , Proteína BRCA1/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Senescência Celular/efeitos da radiação , Quinase do Ponto de Checagem 2 , Proteínas Cromossômicas não Histona , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Doxorrubicina/toxicidade , Fibroblastos/metabolismo , Fibroblastos/patologia , Raios gama , Instabilidade Genômica/efeitos dos fármacos , Instabilidade Genômica/efeitos da radiação , Histonas/genética , Histonas/metabolismo , Peróxido de Hidrogênio/toxicidade , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Knockout , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
5.
Mol Cell ; 32(1): 11-20, 2008 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-18851829

RESUMO

Germline mutations of BRCA1 predispose women to breast and ovarian cancers. However, the downstream mediators of BRCA1 function in tumor suppression remain elusive. We found that human BRCA1-associated breast cancers have lower levels of SIRT1 than their normal controls. We further demonstrated that mammary tumors from Brca1 mutant mice have low levels of Sirt1 and high levels of Survivin, which is reversed by induced expression of Brca1. BRCA1 binds to the SIRT1 promoter and increases SIRT1 expression, which in turn inhibits Survivin by changing the epigenetic modification of histone H3. Absence of SIRT1 blocks the regulation of Survivin by BRCA1. Furthermore, we demonstrated that activation of Sirt1 and inhibition of Survivin expression by resveratrol elicit a more profound inhibitory effect on Brca1 mutant cancer cells than on Brca1-wild-type cancer cells both in vitro and in vivo. These findings suggest that resveratrol treatment serves as an excellent strategy for targeted therapy for BRCA1-associated breast cancer.


Assuntos
Genes BRCA1 , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Sirtuínas/genética , Sirtuínas/metabolismo , Animais , Antineoplásicos Fitogênicos/farmacologia , Proteína BRCA1/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Mutação em Linhagem Germinativa , Humanos , Proteínas Inibidoras de Apoptose , Neoplasias Mamárias Experimentais/tratamento farmacológico , Camundongos , Camundongos Mutantes , Camundongos Nus , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Interferência de RNA , Proteínas Repressoras , Resveratrol , Sirtuína 1 , Estilbenos/farmacologia , Survivina
6.
Nat Genet ; 39(9): 1145-50, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17694057

RESUMO

Premature fusion of one or more of the cranial sutures (craniosynostosis) in humans causes over 100 skeletal diseases, which occur in 1 of approximately 2,500 live births. Among them is Apert syndrome, one of the most severe forms of craniosynostosis, primarily caused by missense mutations leading to amino acid changes S252W or P253R in fibroblast growth factor receptor 2 (FGFR2). Here we show that a small hairpin RNA targeting the dominant mutant form of Fgfr2 (Fgfr2(S252W)) completely prevents Apert-like syndrome in mice. Restoration of normal FGFR2 signaling is manifested by an alteration of the activity of extracellular signal-regulated kinases 1 and 2 (ERK1/2), implicating the gene encoding ERK and the genes downstream of it in disease expressivity. Furthermore, treatment of the mutant mice with U0126, an inhibitor of mitogen-activated protein (MAP) kinase kinase 1 and 2 (MEK1/2) that blocks phosphorylation and activation of ERK1/2, significantly inhibits craniosynostosis. These results illustrate a pathogenic role for ERK activation in craniosynostosis resulting from FGFR2 with the S252W substitution and introduce a new concept of small-molecule inhibitor-mediated prevention and therapy for diseases caused by gain-of-function mutations in the human genome.


Assuntos
Craniossinostoses/genética , MAP Quinases Reguladas por Sinal Extracelular/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Interferência de RNA , Transdução de Sinais/genética , Animais , Sequência de Bases , Butadienos/farmacologia , Craniossinostoses/patologia , Craniossinostoses/prevenção & controle , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Immunoblotting , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Nitrilas/farmacologia , Fenótipo , Fosforilação/efeitos dos fármacos , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Fatores de Tempo
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(1): 45-8, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25616292

RESUMO

OBJECTIVE: To summarize and analyze neonatal screening results for congenital hypothyroidism (CH) in parts of Yunnan Province, China. METHODS: A total of 236 218 newborns (121 463 males and 114 755 females) who were born in Zhaotong City, Qujing City, Lijiang City, and Diqing Tibetan Autonomous Prefecture of Yunnan Province, China, between July 2012 and April 2014 were screened for CH. The original blood smear was re-tested if the thyroid stimulating hormone (TSH) level in heel blood was ≥8 µIU/L in the initial screening. The newborns with positive TSH results were called back for further diagnosis by measuring blood TSH and free thyroxine (FT4) levels. RESULTS: Among 236 218 newborns, the pass rate of blood smears, re-acquisition rate of unqualified blood smears, and recall rate of suspected cases were 96.67%, 81.75%, and 73.02%, respectively. Sixty-six cases of CH were confirmed, among which 36 were male infants and 30 were female infants (P>0.05). The incidence rate of CH was 1/3 579, which was significantly lower than the national average rate (1/2 034; P<0.01). The gestational age of CH newborns was mostly between 37 to 42 weeks, and only 3% were born at a gestational age of >42 weeks. Most of the CH newborns had normal birth weight. The CH newborns with a body length of <50 cm accounted for 32%. CONCLUSIONS: The incidence of CH in Yunnan Province is lower than the national average. There are no specific clinical features in CH newborns. The neonatal screening in Yunnan Province needs further improvement.


Assuntos
Hipotireoidismo Congênito/epidemiologia , Triagem Neonatal , China/epidemiologia , Hipotireoidismo Congênito/sangue , Feminino , Humanos , Recém-Nascido , Masculino , Tireotropina/sangue
8.
Am J Physiol Endocrinol Metab ; 306(7): E824-37, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24496310

RESUMO

Peroxisome proliferator-activated receptor-α (PPARα) mediates metabolic remodeling, resulting in enhanced mitochondrial and peroxisomal ß-oxidation of fatty acids. In addition to the physiological stimuli of fasting and high-fat diet, PPARα is activated by the fibrate class of drugs for the treatment of dyslipidemia. Sirtuin 1 (SIRT1), an important regulator of energy homeostasis, was downregulated in fibrate-treated wild-type mice, suggesting PPARα regulation of Sirt1 gene expression. The impact of SIRT1 loss on PPARα functionality in vivo was assessed in hepatocyte-specific knockout mice that lack the deacetylase domain of SIRT1 (Sirt1(ΔLiv)). Knockout mice were treated with fibrates or fasted for 24 h to activate PPARα. Basal expression of the PPARα target genes Cyp4a10 and Cyp4a14 was reduced in Sirt1(ΔLiv) mice compared with wild-type mice. However, no difference was observed between wild-type and Sirt1(ΔLiv) mice in either fasting- or fibrate-mediated induction of PPARα target genes. Similar to the initial results, there was no difference in fibrate-activated PPARα gene induction. To assess the relationship between SIRT1 and PPARα in a pathophysiological setting, Sirt1(ΔLiv) mice were maintained on a high-fat diet for 14 wk, followed by fibrate treatment. Sirt1(ΔLiv) mice exhibited increased body mass compared with control mice. In the context of a high-fat diet, Sirt1(ΔLiv) mice did not respond to the cholesterol-lowering effects of the fibrate treatment. However, there were no significant differences in PPARα target gene expression. These results suggest that, in vivo, SIRT1 deacetylase activity does not significantly impact induced PPARα activity.


Assuntos
Ácidos Fíbricos/farmacologia , Fígado/metabolismo , PPAR alfa/fisiologia , Sirtuína 1/fisiologia , Animais , Proliferação de Células/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/fisiologia , Fígado/citologia , Fígado/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , PPAR alfa/agonistas , PPAR alfa/genética , Regulação para Cima/efeitos dos fármacos
9.
Hepatology ; 57(6): 2458-68, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23325555

RESUMO

UNLABELLED: Patient-specific induced pluripotent stem cells (iPSCs) represent a potential source for developing novel drug and cell therapies. Although increasing numbers of disease-specific iPSCs have been generated, there has been limited progress in iPSC-based drug screening/discovery for liver diseases, and the low gene-targeting efficiency in human iPSCs warrants further improvement. Using iPSC lines from patients with alpha-1 antitrypsin (AAT) deficiency, for which there is currently no drug or gene therapy available, we established a platform to discover new drug candidates and correct disease-causing mutation with a high efficiency. A high-throughput format screening assay, based on our hepatic differentiation protocol, was implemented to facilitate automated quantification of cellular AAT accumulation using a 96-well immunofluorescence reader. To expedite the eventual application of lead compounds to patients, we conducted drug screening utilizing our established library of clinical compounds (the Johns Hopkins Drug Library) with extensive safety profiles. Through a blind large-scale drug screening, five clinical drugs were identified to reduce AAT accumulation in diverse patient iPSC-derived hepatocyte-like cells. In addition, using the recently developed transcription activator-like effector nuclease technology, we achieved high gene-targeting efficiency in AAT-deficiency patient iPSCs with 25%-33% of the clones demonstrating simultaneous targeting at both diseased alleles. The hepatocyte-like cells derived from the gene-corrected iPSCs were functional without the mutant AAT accumulation. This highly efficient and cost-effective targeting technology will broadly benefit both basic and translational applications. CONCLUSIONS: Our results demonstrated the feasibility of effective large-scale drug screening using an iPSC-based disease model and highly robust gene targeting in human iPSCs, both of which are critical for translating the iPSC technology into novel therapies for untreatable diseases.


Assuntos
Hepatócitos/efeitos dos fármacos , Hepatopatias/terapia , Células-Tronco Pluripotentes/efeitos dos fármacos , Reparo Gênico Alvo-Dirigido/métodos , Deficiência de alfa 1-Antitripsina/terapia , Diferenciação Celular , Células Cultivadas , Hepatócitos/citologia , Humanos , Hepatopatias/genética
10.
Nat Med ; 13(9): 1096-101, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17721544

RESUMO

In thalassemia, deficient globin-chain production during erythropoiesis results in anemia. Thalassemia may be further complicated by iron overload (frequently exacerbated by blood transfusion), which induces numerous endocrine diseases, hepatic cirrhosis, cardiac failure and even death. Accumulation of iron in the absence of blood transfusions may result from inappropriate suppression of the iron-regulating peptide hepcidin by an erythropoietic mechanism. To test this hypothesis, we examined erythroblast transcriptome profiles from 15 healthy, nonthalassemic donors. Growth differentiation factor 15 (GDF15), a member of the transforming growth factor-beta superfamily, showed increased expression and secretion during erythroblast maturation. Healthy volunteers had mean GDF15 serum concentrations of 450 +/- 50 pg/ml. In comparison, individuals with beta-thalassemia syndromes had elevated GDF15 serum levels (mean 66,000 +/- 9,600 pg/ml; range 4,800-248,000 pg/ml; P < 0.05) that were positively correlated with the levels of soluble transferrin receptor, erythropoietin and ferritin. Serum from thalassemia patients suppressed hepcidin mRNA expression in primary human hepatocytes, and depletion of GDF15 reversed hepcidin suppression. These results suggest that GDF15 overexpression arising from an expanded erythroid compartment contributes to iron overload in thalassemia syndromes by inhibiting hepcidin expression.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Citocinas/sangue , Regulação da Expressão Gênica , Talassemia/sangue , Talassemia/genética , Perfilação da Expressão Gênica , Fator 15 de Diferenciação de Crescimento , Hepcidinas , Humanos , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Valores de Referência , Transcrição Gênica
11.
J Biol Chem ; 287(50): 41903-13, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23076146

RESUMO

The human body has a remarkable ability to regulate inflammation, a biophysical response triggered by virus infection and tissue damage. Sirt6 is critical for metabolism and lifespan; however, its role in inflammation is unknown. Here we show that Sirt6-null (Sirt6(-/-)) mice developed chronic liver inflammation starting at ∼2 months of age, and all animals were affected by 7-8 months of age. Deletion of Sirt6 in T cells or myeloid-derived cells was sufficient to induce liver inflammation and fibrosis, albeit to a lesser degree than that in the global Sirt6(-/-) mice, suggesting that Sirt6 deficiency in the immune cells is the cause. Consistently, macrophages derived from the bone marrow of Sirt6(-/-) mice showed increased MCP-1, IL-6, and TNFα expression levels and were hypersensitive to LPS stimulation. Mechanistically, SIRT6 interacts with c-JUN and deacetylates histone H3 lysine 9 (H3K9) at the promoter of proinflammatory genes whose expression involves the c-JUN signaling pathway. Sirt6-deficient macrophages displayed hyperacetylation of H3K9 and increased occupancy of c-JUN in the promoter of these genes, leading to their elevated expression. These data suggest that Sirt6 plays an anti-inflammatory role in mice by inhibiting c-JUN-dependent expression of proinflammatory genes.


Assuntos
Regulação da Expressão Gênica , Hepatite Crônica/metabolismo , Cirrose Hepática/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Transdução de Sinais , Sirtuínas/metabolismo , Animais , Linhagem Celular Transformada , Citocinas/biossíntese , Citocinas/genética , Hepatite Crônica/genética , Hepatite Crônica/patologia , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , Camundongos , Camundongos Knockout , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-jun/genética , Sirtuínas/genética , Linfócitos T/metabolismo , Linfócitos T/patologia
12.
Blood ; 117(2): 440-50, 2011 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-20966168

RESUMO

SIRT1 is a founding member of a sirtuin family of 7 proteins and histone deacetylases. It is involved in cellular resistance to stress, metabolism, differentiation, aging, and tumor suppression. SIRT1(-/-) mice demonstrate embryonic and postnatal development defects. We examined hematopoietic and endothelial cell differentiation of SIRT1(-/-) mouse embryonic stem cells (ESCs) in vitro, and hematopoietic progenitors in SIRT1(+/+)(+/-), and (-/-) mice. SIRT1(-/-) ESCs formed fewer mature blast cell colonies. Replated SIRT1(-/-) blast colony-forming cells demonstrated defective hematopoietic potential. Endothelial cell production was unaltered, but there were defects in formation of a primitive vascular network from SIRT1(-/-)-derived embryoid bodies. Development of primitive and definitive progenitors derived from SIRT1(-/-) ESCs were also delayed and/or defective. Differentiation delay/defects were associated with delayed capacity to switch off Oct4, Nanog and Fgf5 expression, decreased ß-H1 globin, ß-major globin, and Scl gene expression, and reduced activation of Erk1/2. Ectopic expression of SIRT1 rescued SIRT1(-/-) ESC differentiation deficiencies. SIRT1(-/-) yolk sacs manifested fewer primitive erythroid precursors. SIRT1(-/-) and SIRT1(+/-) adult marrow had decreased numbers and cycling of hematopoietic progenitors, effects more apparent at 5%, than at 20%, oxygen tension, and these progenitors survived less well in vitro under conditions of delayed growth factor addition. This suggests a role for SIRT1 in ESC differentiation and mouse hematopoiesis.


Assuntos
Envelhecimento , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Sirtuína 1/metabolismo , Animais , Western Blotting , Separação Celular , Células-Tronco Embrionárias/citologia , Citometria de Fluxo , Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Sirtuína 1/deficiência , Sirtuína 1/genética
13.
Front Immunol ; 14: 1115031, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36860868

RESUMO

Background: Inflammatory mechanisms play important roles in intracerebral hemorrhage (ICH) and have been linked to the development of stroke-associated pneumonia (SAP). The neutrophil-to-lymphocyte ratio (NLR), systemic immune-inflammation index (SII), platelet-to-lymphocyte ratio (PLR) and systemic inflammation response index (SIRI) are inflammatory indexes that influence systemic inflammatory responses after stroke. In this study, we aimed to compare the predictive value of the NLR, SII, SIRI and PLR for SAP in patients with ICH to determine their application potential in the early identification of the severity of pneumonia. Methods: Patients with ICH in four hospitals were prospectively enrolled. SAP was defined according to the modified Centers for Disease Control and Prevention criteria. Data on the NLR, SII, SIRI and PLR were collected at admission, and the correlation between these factors and the clinical pulmonary infection score (CPIS) was assessed through Spearman's analysis. Results: A total of 320 patients were enrolled in this study, among whom 126 (39.4%) developed SAP. The results of the receiver operating characteristic (ROC) analysis revealed that the NLR had the best predictive value for SAP (AUC: 0.748, 95% CI: 0.695-0.801), and this outcome remained significant after adjusting for other confounders in multivariable analysis (RR=1.090, 95% CI: 1.029-1.155). Among the four indexes, Spearman's analysis showed that the NLR was the most highly correlated with the CPIS (r=0.537, 95% CI: 0.395-0.654). The NLR could effectively predict ICU admission (AUC: 0.732, 95% CI: 0.671-0.786), and this finding remained significant in the multivariable analysis (RR=1.049, 95% CI: 1.009-1.089, P=0.036). Nomograms were created to predict the probability of SAP occurrence and ICU admission. Furthermore, the NLR could predict a good outcome at discharge (AUC: 0.761, 95% CI: 0.707-0.8147). Conclusions: Among the four indexes, the NLR was the best predictor for SAP occurrence and a poor outcome at discharge in ICH patients. It can therefore be used for the early identification of severe SAP and to predict ICU admission.


Assuntos
Pneumonia , Acidente Vascular Cerebral , Estados Unidos , Humanos , Neutrófilos , Pneumonia/diagnóstico , Inflamação , Hemorragia Cerebral/diagnóstico , Linfócitos
14.
J Tradit Chin Med ; 32(1): 40-4, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22594100

RESUMO

OBJECTIVE: To compare the effects on the body surface of different kinds of placebo/sham acupuncture with that of traditional needling sensation acupuncture. METHODS: Point Neiguan (PC 6) of 29 healthy subjects, 19 males and 10 females, was stimulated with needling sensation, shallow, placebo and deep acupuncture at the non-acupoint. After stimulation with different methods of acupuncture, the change in perfusion of the micrangium in the skin surface around the elbow joint, with Point Quze (PC 3) as its center, was observed with laser Doppler blood-flow imaging. RESULTS: Judging from the absolute value of perfusion of the skin surface micrangium, several methods of acupuncture can cause change in blood flow. The ratio of blood-flow perfusion in the meridian area in and around Quze declined before and after needling insertion in needling sensation acupuncture and shallow acupuncture. This observation did not occur in placebo and non-acupoint acupuncture. Needling sensation acupuncture at an acupoint can relatively reduce the perfusion of the micrangium in the projective area of the meridian where the acupoint is located on the body surface (P < 0.05), indicating the specificity of meridians. CONCLUSIONS: Stimulation of an acupoint or a point on the body surface with any type of acupuncture can cause change in blood flow in the skin near the needling point. However, the biological mechanism underlying this phenomenon needs to be further explored.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Fluxo Sanguíneo Regional , Pele/irrigação sanguínea , Adulto , Feminino , Humanos , Masculino , Meridianos , Adulto Jovem
15.
Mitochondrial DNA B Resour ; 7(1): 275-276, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35097214

RESUMO

Spirea japonica var. acuminata Franch. (Rosaceae) is a Chinese herbal medicine distributed in southwest and east China. The first complete chloroplast genome of Spirea japonica var. acuminata Franch. was assembled and reported in this study. The genome is 153,822 bp in length and contained 125 encoded genes in total, including 80 protein-coding genes, eight ribosomal RNA genes, and 37 transfer RNA genes. The phylogenomic analysis showed that Spirea japonica var. acuminata Franch. was closely related to Spirea blumei, Spirea trilobata, Spirea mongolica and Spirea insularis according to the current sampling extent.

16.
PhytoKeys ; 206: 109-117, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761270

RESUMO

A new propaguliferous moss species, Pohliatibetana X.R.Wang & X.M.Shao (Mielichhoferiaceae), from Tibet, southwest China, is described. The new species differs most saliently from other species of Pohlia by its combination of slender plants, loosely attached leaves and axillary solitary, and dark red and flower-like gemmae. In this paper, the line drawings, photographs, habit of the new species are provided and a morphological comparison of it with the similar species is made.

17.
Mitochondrial DNA B Resour ; 7(3): 505-506, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342798

RESUMO

Spiraea×vanhouttei (Rosaceae) is a frequently planted Spiraea species that is distributed in Shandong Province, Jiangsu Province, and Guangdong Province, China. The first complete chloroplast genome of Spiraea×vanhouttei was determined and described in this study. The genome is 155,957 bp in length and contained 129 encoded genes in total, including 84 protein-coding genes, eight ribosomal RNA genes, and 37 transfer RNA genes. The phylogenomic analysis showed that Spiraea×vanhouttei was closely related to Spiraea blumei according to the current sampling extent.

18.
Front Plant Sci ; 13: 985372, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212368

RESUMO

Numerous temperate plants and animals on the Qinghai-Tibet Plateau (QTP) are hypothesized to have differentiated due to vicariant allopatric speciation associated with the geologic uplifts. However, this hypothesis has rarely been tested through a phylogeographic study of relative species in a broader geographic context, including the QTP, Tianshan Mountains, Mongolian Plateau, and surrounding regions. To understand the speciation and diversification process of plants across this wide area, phylogeographic analysis were examined from Scrophularia incisa and two other closely relative species comprising S. kiriloviana and S. dentata. Thirty-two populations of the three close relatives were genotyped using chloroplast DNA fragments and nuclear microsatellite loci to assess population structure and diversity, supplemented by phylogenetic dating, ancestral area reconstructions and species distribution modelings, as well as niche identity tests. Our chloroplast DNA (cpDNA) phylogeny showed that this monophyletic group of desert and steppe semi-shrub is derived from a Middle Pliocene ancestor of the Central Asia. Lineages in Central Asia vs. China diverged through climate/tectonic-induced vicariance during Middle Pliocene. Genetic and ENM data in conjunction with niche differentiation analyses support that the divergence of S. incisa, S. dentata and S. kiriloviana in China lineage proceeded through allopatric speciation, might triggered by early Pleistocene climate change of increase of aridification and enlargement of deserts, while subsequent climate-induced cycles of range contractions/expansions enhanced the geographical isolation and habit fragmentation of these taxa. These findings highlight the importance of the Plio-Pleistocene climate change in shaping genetic diversity and driving speciation in temperate steppes and deserts of Northwestern China.

19.
Genes (Basel) ; 13(10)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36292609

RESUMO

The genus Convallaria (Asparagaceae) comprises three herbaceous perennial species that are widely distributed in the understory of temperate deciduous forests in the Northern Hemisphere. Although Convallaria species have high medicinal and horticultural values, studies related to the phylogenetic analysis of this genus are few. In the present study, we assembled and reported five complete chloroplast (cp) sequences of three Convallaria species (two of C. keiskei Miq., two of C. majalis L., and one of C. montana Raf.) using Illumina paired-end sequencing data. The cp genomes were highly similar in overall size (161,365-162,972 bp), and all consisted of a pair of inverted repeats (IR) regions (29,140-29,486 bp) separated by a large single-copy (LSC) (85,183-85,521 bp) and a small single-copy (SSC) region (17,877-18,502 bp). Each cp genome contained the same 113 unique genes, including 78 protein-coding genes, 30 transfer RNA genes, and 4 ribosomal RNA genes. Gene content, gene order, AT content and IR/SC boundary structure were nearly identical among all of the Convallaria cp genomes. However, their lengths varied due to contraction/expansion at the IR/LSC borders. Simple sequence repeat (SSR) analyses indicated that the richest SSRs are A/T mononucleotides. Three highly variable regions (petA-psbJ, psbI-trnS and ccsA-ndhD) were identified as valuable molecular markers. Phylogenetic analysis of the family Asparagaceae using 48 cp genome sequences supported the monophyly of Convallaria, which formed a sister clade to the genus Rohdea. Our study provides a robust phylogeny of the Asparagaceae family. The complete cp genome sequences will contribute to further studies in the molecular identification, genetic diversity, and phylogeny of Convallaria.


Assuntos
Asparagaceae , Convallaria , Genoma de Cloroplastos , Genoma de Cloroplastos/genética , Filogenia , Convallaria/genética , Asparagaceae/genética , RNA de Transferência/genética
20.
J Biol Chem ; 285(47): 36387-94, 2010 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-20851890

RESUMO

Resveratrol (RSV) is a naturally occurring polyphenol that has been found to exert antioxidant, anti-inflammatory, and neuroprotective properties. However, how RSV exerts its beneficial health effects remains largely unknown. Here, we show that RSV inhibits insulin- and leucine-stimulated mTOR signaling in C2C12 fibroblasts via a Sirt1-independent mechanism. Treating C2C12 cells with RSV dramatically inhibited insulin-stimulated Akt, S6 kinase, and 4E-BP1 phosphorylation but had little effect on tyrosine phosphorylation of the insulin receptor and activation of the p44/42 MAPK signaling pathway. RSV treatment also partially blocked mTOR and S6 kinase phosphorylation in TSC1/2-deficient mouse embryonic fibroblasts, suggesting the presence of an inhibitory site downstream of TSC1/2. Knocking out PDK1 or suppressing AMP-activated protein kinase had little effect on leucine-stimulated mTOR signaling. On the other hand, RSV significantly increased the association between mTOR and its inhibitor, DEPTOR. Furthermore, the inhibitory effect of RSV on leucine-stimulated mTOR signaling was greatly reduced in cells in which the expression levels of DEPTOR were suppressed by RNAi. Taken together, our studies reveal that RSV inhibits leucine-stimulated mTORC1 activation by promoting mTOR/DEPTOR interaction and thus uncover a novel mechanism by which RSV negatively regulates mTOR activity.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Vasodilatadores/farmacologia , Animais , Western Blotting , Células Cultivadas , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Imunoprecipitação , Peptídeos e Proteínas de Sinalização Intracelular , Leucina/farmacologia , Camundongos , Camundongos Knockout , Mioblastos/citologia , Mioblastos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/fisiologia , Piruvato Desidrogenase Quinase de Transferência de Acetil , Resveratrol , Sirtuína 1/fisiologia , Serina-Treonina Quinases TOR/genética , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/fisiologia
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