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1.
Proc Natl Acad Sci U S A ; 117(52): 32989-32995, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33288692

RESUMO

Tibet's ancient topography and its role in climatic and biotic evolution remain speculative due to a paucity of quantitative surface-height measurements through time and space, and sparse fossil records. However, newly discovered fossils from a present elevation of ∼4,850 m in central Tibet improve substantially our knowledge of the ancient Tibetan environment. The 70 plant fossil taxa so far recovered include the first occurrences of several modern Asian lineages and represent a Middle Eocene (∼47 Mya) humid subtropical ecosystem. The fossils not only record the diverse composition of the ancient Tibetan biota, but also allow us to constrain the Middle Eocene land surface height in central Tibet to ∼1,500 ± 900 m, and quantify the prevailing thermal and hydrological regime. This "Shangri-La"-like ecosystem experienced monsoon seasonality with a mean annual temperature of ∼19 °C, and frosts were rare. It contained few Gondwanan taxa, yet was compositionally similar to contemporaneous floras in both North America and Europe. Our discovery quantifies a key part of Tibetan Paleogene topography and climate, and highlights the importance of Tibet in regard to the origin of modern Asian plant species and the evolution of global biodiversity.

2.
J Cardiovasc Electrophysiol ; 32(7): 1896-1906, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34053145

RESUMO

INTRODUCTION: The complex electrophysiological phenomena related to the atrioventricular node (AVN) are due to its complex anatomical structures. Aside from the inferior nodal extension (INE), other node-like tissues, such as the retroaortic node (RN), have been described less extensively and may also share the mechanism of normal conduction and abnormal conduction in AVN re-entrant tachycardia. METHODS: High-density sections of the entire AVN were obtained from rats and rabbits. Fibrosis was analyzed by Masson's trichrome staining. Connexin (Cx43, Cx40, and Cx45) and ion channel (Nav 1.5, Cav 3.1, and HCN4) proteins were immunohistochemically labeled for the analysis of tissue features. Three-dimensional (3D) reconstruction of the AV junction was performed to clarify the relationships among different structures. RESULTS: The RN expressed the same connexin isoforms as the compact node (CN) and INE. Nav 1.5 labeling was observed at low levels in the CN, RN, and INE, where Cav 3.1 and HCN4 were expressed. The CN connected with the RN in a narrow strip pattern at the start of the CN. The RN presented as a shuttle shape and was the only tissue directly connected with the atrium in the anterior septum. CONCLUSION: The RN connects with the AVN anatomically, suggesting that direct electrical conduction occurs between them. The entrance of the atria into the AVN is distal to the RN, which may form the fast AVN pathway.


Assuntos
Nó Atrioventricular , Fascículo Atrioventricular , Animais , Átrios do Coração , Coelhos , Ratos
3.
J Cell Physiol ; 234(7): 10554-10565, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30623413

RESUMO

TCEA3 is a member of the transcription elongation factor family that not only promotes transcription but may also participate in other cytoplasmic processes. However, its mechanisms of action remain unclear. Our previous study indicated that TCEA3 may affect muscle differentiation. In this study, we investigated the expression and localization of TCEA3 in C2C12 cells and examined the role of TCEA3 in differentiation, its interaction with other cell proteins, and mechanisms of action. We found that the expression of TCEA3 increased gradually with an increase in the number of differentiation days and that it is mainly expressed in the cytoplasm of C2C12 cells, of which it promotes differentiation. Coimmunoprecipitation experiments and western blot analysis revealed that TCEA3 interacts with Annexin A1 (ANXA1), which is located in the cytoplasm and also promotes cell differentiation. Collectively, our results indicate that TCEA3 promotes cell differentiation by interacting with ANXA1 and affecting transforming growth factor-ß signaling pathways.


Assuntos
Anexina A1/genética , Transcrição Gênica , Fatores de Elongação da Transcrição/genética , Fator de Crescimento Transformador beta/genética , Animais , Diferenciação Celular/genética , Linhagem Celular , Regulação da Expressão Gênica no Desenvolvimento/genética , Camundongos , Transdução de Sinais/genética
4.
J Bone Miner Metab ; 37(3): 430-440, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30097709

RESUMO

An aggressive proliferation of synoviocytes is the hallmark of rheumatoid arthritis (RA). Emerging evidence shows that inhibiting the NF-κB signaling pathway with 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] may be a therapeutic approach for controlling inflammatory diseases. In this study, we demonstrated the protective effects of three different 1,25(OH)2D3 concentration on adjuvant-induced arthritis (AA) rats through the NF-κB signaling pathway and their pro-apoptotic roles in cultured adjuvant-induced arthritis synoviocytes (AIASs). AA rats were prepared by injecting complete Freund's adjuvant and independently given daily intraperitoneal injection of 1,25(OH)2D3 at concentrations of 50, 100, and 300 ng/day/kg. Subsequently, AIASs were isolated from the inflamed joints of AA rats to test the effects of 1,25(OH)2D3 on AIASs in vitro. Intraperitoneal injection of 1,25-(OH)2D3 was found to induce a concentration- and time-dependent improvement in relieving the symptoms of AA. We found an increased paw withdrawal thermal latency (PWTL) in the affected paw of AA rats as the concentration of 1,25-(OH)2D3 increased. 1,25-(OH)2D3 treatment reduced levels of inflammatory factors in synovial tissues of AA rats. In the case of cultured AIASs, 1,25-(OH)2D3 was shown to inhibit cell proliferation and induce cell apoptosis in a concentration-dependent manner. Additionally, 1,25-(OH)2D3 inhibited the activation of the NF-κB signaling pathway. In conclusion, our study provides evidence emphasizing that 1,25(OH)2D3 has the potential to attenuate disease severity in RA potentially due to its contributory role in synoviocyte proliferation and apoptosis. The protective role of 1,25(OH)2D3 against RA depends on the NF-κB signaling pathway.


Assuntos
Apoptose/efeitos dos fármacos , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , NF-kappa B/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais , Sinoviócitos/patologia , Vitamina D/análogos & derivados , Animais , Artrite Experimental/diagnóstico por imagem , Artrite Experimental/metabolismo , Artrite Reumatoide/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Hiperplasia , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Masculino , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/patologia , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/metabolismo , Vitamina D/farmacologia , Vitamina D/uso terapêutico
5.
Exp Cell Res ; 366(2): 199-204, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29577896

RESUMO

C2C12 murine myoblasts are a common model for studying muscle differentiation. Platelet endothelial aggregation receptor-1 (PEAR1), an epidermal growth factor repeat-containing transmembrane receptor, is known to participate in platelet contact-induced activation. In the present study, we demonstrated that PEAR1 is involved in the differentiation of C2C12 murine myoblasts. Western blotting and immunofluorescence staining were used to determine PEAR1 expression and localization during C2C12 cell differentiation. Subsequently, PEAR1 expression was activated and inhibited using clustered regularly interspaced short palindromic repeats-dCas9 technology to explore its effects on this process. PEAR1 expression was found to increase over the course of C2C12 cell differentiation. This protein was predominately localized on the membrane of these cells, where it clustered upon induction of differentiation. Expression of the myogenic markers Desmin, MYOG, and MYH2 revealed that PEAR1 positively regulated C2C12 cell differentiation. Moreover, induction of muscle injury by administration of bupivacaine to mice indicated that PEAR1 might play a role in muscle regeneration. In summary, our study confirmed the involvement of PEAR1 in C2C12 cell differentiation, contributing to our understanding of the molecular mechanisms underlying muscle development.


Assuntos
Diferenciação Celular , Regulação da Expressão Gênica no Desenvolvimento , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/citologia , Mioblastos/citologia , Agregação Plaquetária , Receptores de Superfície Celular/fisiologia , Animais , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos ICR , Músculo Esquelético/lesões , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , Receptores de Superfície Celular/genética
6.
Biochem Biophys Res Commun ; 484(4): 827-832, 2017 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-28161635

RESUMO

Bovine muscle-derived satellite cells (MDSCs) are important for animal growth. In this study, the effect of transcription elongation factor A3 (TCEA3) on bovine MDSC differentiation was investigated. Western blotting, immunofluorescence assays, and cytoplasmic and nuclear protein isolation and purification techniques were used to determine the expression pattern and protein localization of TCEA3 in bovine MDSCs during in vitro differentiation. TCEA3 expression was upregulated using the CRISPR/Cas9 technique to study its effects on MDSC differentiation in vitro. TCEA3 expression gradually increased during the in vitro differentiation of bovine MDSCs and peaked on the 5th day of differentiation. TCEA3 was mainly localized in the cytoplasm of bovine MDSCs, and its expression was not detected in the nucleus. The level of TCEA3 was relatively higher in myotubes at a higher degree of differentiation than during early differentiation. After transfection with a TCEA3-activating plasmid vector (TCEA3 overexpression) for 24 h, the myotube fusion rate, number of myotubes, and expression levels of the muscle differentiation-related loci myogenin (MYOG) and myosin heavy chain 3 (MYH3) increased significantly during the in vitro differentiation of bovine MDSCs. After transfection with a TCEA3-inhibiting plasmid vector for 24 h, the myotube fusion rate, number of myotubes, and expression levels of MYOG and MYH3 decreased significantly. Our results indicated, for the first time, that TCEA3 promotes the differentiation of bovine MDSCs and have implications for meat production and animal rearing.


Assuntos
Diferenciação Celular/fisiologia , Desenvolvimento Muscular/fisiologia , Mioblastos/citologia , Mioblastos/metabolismo , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Animais , Bovinos , Células Cultivadas
7.
Biochem Biophys Res Commun ; 493(4): 1457-1463, 2017 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-28780350

RESUMO

ELOVL3 is involved in elongating saturated and monounsaturated fatty acids, and is a critical enzyme for lipid accumulation in brown adipocytes during the early phase of tissue recruitment. In addition, ELOVL3 is related to increased fatty acid oxidation in brown adipocytes. However, the potential functions of ELOVL3 in bovine cells remain unclear. Herein, we aimed to elucidate the effect of the ELOVL3 on the differentiation of bovine skeletal muscle-derived satellite cells (MDSCs). Western blot and immunofluorescence analyses were used for elucidating ELOVL3 expression pattern in bovine MDSCs during differentiation in vitro. We activated or inhibited ELOVL3 to study the effect of alterations in its expression on in vitro differentiation of bovine MDSCs. ELOVL3 expression increased gradually during bovine MDSC differentiation, and its levels were higher in the more highly differentiated myotubes. Activation of ELOVL3 promoted MDSC differentiation, while inhibition of ELOVL3 hindered differentiation of these cells. Here, for the first time, we demonstrate the importance of ELOVL3 during bovine MDSC differentiation, which may assist in increasing beef cattle muscularity.


Assuntos
Acetiltransferases/metabolismo , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/metabolismo , Acetiltransferases/antagonistas & inibidores , Acetiltransferases/genética , Animais , Sistemas CRISPR-Cas , Bovinos , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Elongases de Ácidos Graxos , Regulação da Expressão Gênica no Desenvolvimento , Desenvolvimento Muscular/genética , Desenvolvimento Muscular/fisiologia , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética
8.
Cell Mol Biol Lett ; 21: 8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28536611

RESUMO

BACKGROUND: The differentiation of skeletal muscle-derived satellite cells (MDSCs) is important in controlling muscle growth, improving livestock muscle quality, and healing of muscle-related disease. MicroRNAs (miRNAs) are a class of gene expression regulatory factors, which play critical roles in the regulation of muscle cell differentiation. This study aimed to compare the expression profile of miRNAs in MDSC differentiation, and to investigate the miRNAs which are involved in MDSC differentiation. METHOD: Total RNA was extracted from MDSCs at three different stages of differentiation (MDSC-P, MDSC-D1 and MDSC-D3, representing 0, 1 and 3 days after differentiation, respectively), and used to construct small RNA libraries for RNA sequencing (RNA-seq). RESULTS: The results showed that in total 617 miRNAs, including 53 novel miRNA candidates, were identified. There were 9 up-expressed, 165 down-expressed, and 15 up-expressed, 145 down-expressed in MDSC-D1 and MDSC-D3, respectively, compared to those in MDSC-P. Also, 17 up-expressed, 55 down-expressed miRNAs were observed in MDSC-D3 compared to those in MDSC-D1. All known miRNAs belong to 237 miRNA gene families. Furthermore, we observed some sequence variants and base edits of the miRNAs. GO and KEGG pathway analysis showed that the majority of target genes regulated by miRNAs were involved in cellular metabolism, pathways in cancer, actin cytoskeleton regulation and the MAPK signaling pathway. Regarding the 53 novel miRNAs, there were 7 up-expressed, 31 down-expressed, and 8 up-expressed, 26 down-expressed in MDSC-D1 and MDSC-D3, respectively, compared to those in MDSC-P. The expression levels of 12 selected miRNA genes detected by RT-qPCR were consistent with those generated by deep sequencing. CONCLUSIONS: This study confirmed the authenticity of 564 known miRNAs and identified 53 novel miRNAs which were involved in MDSC differentiation. The identification of novel miRNAs has significantly expanded the repertoire of bovine miRNAs and could contribute to advances in understanding muscle development in cattle.


Assuntos
Diferenciação Celular , MicroRNAs/genética , Células Satélites de Músculo Esquelético/metabolismo , Transcriptoma , Animais , Bovinos , Sequenciamento de Nucleotídeos em Larga Escala , Células Satélites de Músculo Esquelético/fisiologia , Análise de Sequência de RNA
9.
Biochem Biophys Res Commun ; 463(4): 624-31, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26047700

RESUMO

MicroRNAs play critical roles in skeletal muscle development as well as in regulation of muscle cell proliferation and differentiation. Previous study in our laboratory showed that the expression level of miR-2400, a novel and unique miRNA from bovine, had significantly changed in skeletal muscle-derived satellite cells (MDSCs) during differentiation, however, the function and expression pattern for miR-2400 in MDSCs has not been fully understood. In this report, we firstly identified that the expression levels of miR-2400 were down-regulated during MDSCs differentiation by stem-loop RT-PCR. Over-expression and inhibition studies demonstrated that miR-2400 promoted MDSCs proliferation by EdU (5-ethynyl-2' deoxyuridine) incorporation assay and immunofluorescence staining of Proliferating cell nuclear antigen (PCNA). Luciferase reporter assays showed that miR-2400 directly targeted the 3' untranslated regions (UTRs) of myogenin (MYOG) mRNA. These data suggested that miR-2400 could promote MDSCs proliferation through targeting MYOG. Furthermore, we found that miR-2400, which was located within the eighth intron of the Wolf-Hirschhorn syndrome candidate 1-like 1 (WHSC1L1) gene, was down-regulated in MDSCs in a direct correlation with the WHSC1L1 transcript by Clustered regularly interspaced palindromic repeats interference (CRISPRi). In addition, these observations not only provided supporting evidence for the codependent expression of intronic miRNAs and their host genes in vitro, but also gave insight into the role of miR-2400 in MDSCs proliferation.


Assuntos
Proliferação de Células/genética , MicroRNAs/genética , Miogenina/genética , Células Satélites de Músculo Esquelético/citologia , Regiões 3' não Traduzidas , Animais , Bovinos , Diferenciação Celular/genética , Células Cultivadas , Primers do DNA , Regulação para Baixo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Células Satélites de Músculo Esquelético/metabolismo
10.
Cell Mol Biol Lett ; 20(3): 351-73, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26208385

RESUMO

In this study, we utilized high throughput RNA sequencing to obtain a comprehensive gene expression profile of muscle-derived satellite cells (MDSCs) upon induction of differentiation. MDSCs were cultured in vitro and RNA was extracted for sequencing prior to differentiation (MDSC-P), and again during the early and late differentiation (MDSC-D1, and MDSC-D3, respectively) stages. Sequence tags were assembled and analyzed by digital gene expression profile to screen for differentially expressed genes, Gene Ontology annotation, and pathway enrichment analysis. Quantitative real-time PCR was used to confirm the results of RNA sequencing. Our results indicate that certain of genes were changed during skeletal muscle cell development, cell cycle progression, and cell metabolism during differentiation of bovine MDSCs. Furthermore, we identified certain genes that could be used as novel candidates for future research of muscle development. Additionally, the sequencing results indicated that lipid metabolism might be the predominant cellular process that occurs during MDSC differentiation.


Assuntos
Diferenciação Celular/genética , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Células Satélites de Músculo Esquelético/metabolismo , Transcriptoma , Animais , Animais Recém-Nascidos , Bovinos , Células Cultivadas , Ontologia Genética , Anotação de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Int J Ophthalmol ; 17(6): 1086-1093, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895689

RESUMO

AIM: To evaluate the effect of low-degree astigmatism on objective visual quality through the Optical Quality Analysis System (OQAS). METHODS: This study enrolled 46 participants (aged 23 to 30y, 90 eyes) with normal or corrected-to-normal vision. The cylindrical lenses (0, 0.5, 0.75, 1.0, and 1.25 D) were placed at the axial direction (180°, 45°, 90°, and 135°) in front of the eyes with the best correction to form 16 types of regular low-degree astigmatism. OQAS was used to detect the objective visual quality, recorded as the objective scattering index (OSI), OQAS values at contrasts of 100%, 20%, and 9% predictive visual acuity (OV100%, OV20%, and OV9%), modulation transfer function cut-off (MTFcut-off) and Strehl ratio (SR). The mixed effect linear model was used to compare objective visual quality differences between groups and examine associations between astigmatic magnitude and objective visual quality parameters. RESULTS: Apparent negative relationships between the magnitude of low astigmatism and objective visual quality were observed. The increase of OSI per degree of astigmatism at 180°, 45°, 90°, and 135° axis were 0.38 (95%CI: 0.35, 0.42), 0.50 (95%CI: 0.46, 0.53), 0.49 (95%CI: 0.45, 0.54) and 0.37 (95%CI: 0.34, 0.41), respectively. The decrease of MTFcut-off per degree of astigmatism at 180°, 45°, 90°, and 135° axis were -10.30 (95%CI: -11.43, -9.16), -12.73 (95%CI: -13.62, -11.86), -12.75 (95%CI: -13.79, -11.70), and -9.97 (95%CI: -10.92, -9.03), respectively. At the same astigmatism degree, OSI at 45° and 90° axis were higher than that at 0° and 135° axis, while MTFcut-off were lower. CONCLUSION: Low astigmatism of only 0.50 D can significantly reduce the objective visual quality.

12.
iScience ; 26(8): 107313, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37554461

RESUMO

Anatomical structure of mummified wood of Cryptocarya (Lauraceae) from the Upper Pleistocene of Maoming, South China and the woods of 15 extant species of Cryptocarya from China and Malaysia were examined. The fossil wood has been convincingly attributed to extant species Cryptocarya chinensis (Hance) Hemsl. This is the first reliable fossil record of Cryptocarya in Asia. The finding combined with the results of Biomod2 species distribution modeling suggest that the range of C. chinensis in the Late Pleistocene in South China and North Vietnam was very restricted due to increased continental aridity and enhanced temperature seasonality in this region. Thus, modern populations of C. chinensis in Maoming can be considered as glacial relicts. The mines (larval tunnels) produced by the larvae of flies from the genus Phytobia Lioy (Agromyzidae, Diptera) were observed in fossil wood under study. These cambial miners have never been reported in Cryptocarya.

13.
Biomed Environ Sci ; 25(3): 367-71, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22840589

RESUMO

OBJECTIVE: To establish multiplex PCR-based assays for detecting H.influenzae and H.parainfluenzae. And the PCR-based assays were applied to detect the carriage rates of H.influenzae and H.parainfluenzae in nasopharyngeal swab specimens which were collected from healthy children. METHODS: Multiplex primers for species-specific PCR were designed by using DNAstar soft based on the sequences of 16S rRNA genes from genus Haemophilus to detect H.influenzae and H.parainfluenzae. RESULTS: The sensitivity of the 16S rRNA PCR assay for detecting H.influenzae and H.parainfluenzae was 97.53% and 100% respectively, and the specificity was 95.89% and 96.63% respectively. Youden's Index on the ability to detect H.influenzae and H.parainfluenzae was 0.9342 and 0.9663 respectively. 666 nasopharyngeal swab specimens were collected from healthy children. The detection rates of H.influenzae and H.parainfluenzae were 14.11% and 16.07% respectively by using isolation and culture methods. The detection rates of H.influenzae and H.parainfluenzae were 43.54% and 57.96% respectively by 16S rRNA PCR assays. The carriage rates of serotypes a, b, c, d, e, f and non-typeable isolates were 0% (0/666), 0.15% (1/666), 1.20% (8/666), 0.15% (1/666), 1.20% (8/666), 1.80% (12/666), 95.50% (636/666) respectively. CONCLUSION: The multiplex PCR assays were very rapid, reliable and feasible methods for detection of H.influenzae and H.parainfluenzae in pharyngeal swab specimens which were compared to conventional isolation and culture methods. 95.5% of H.influenzae strains in healthy children were nontypeable. The encapsulated or typable strains were mainly three serotypes which was c, e, and f serotype.


Assuntos
Haemophilus influenzae/isolamento & purificação , Haemophilus parainfluenzae/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Nasofaringe/microbiologia , Haemophilus influenzae/classificação , Haemophilus influenzae/genética , Haemophilus parainfluenzae/classificação , Haemophilus parainfluenzae/genética , Humanos , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade
14.
Clin Exp Pharmacol Physiol ; 38(1): 77-83, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21126261

RESUMO

1. In the present study, the temporal and concentration-dependent cardioprotective effects of rapamycin against ischaemia-reperfusion (I/R) injury, as well as the underlying mechanisms, were investigated. 2. Rat Langendorff-perfused isolated hearts were exposed to 40 min global ischaemia followed by 120 min reperfusion. Hearts were perfused with different concentrations of rapamycin before and after ischaemia. Myocardial injury was assessed in terms of infarct size and the release of lactate dehydrogenase (LDH) and creatine kinase (CK). The phosphorylation of Akt, extracellular signal-regulated kinase (ERK) 1/2 and endothelial nitric oxide synthase (eNOS) was determined at the end of reperfusion. 3. When administered prior to ischaemia, 25, 50 and 100 nmol/L rapamycin significantly reduced infarct size compared with control (40.1 ± 1.5, 26.3 ± 4.1 and 21.2 ± 3.4 vs 52.5 ± 4.5%, respectively) without affecting the recovery of ventricular function. No reduction in infarct size was observed when 50 nmol/L rapamycin was administered 10 or 120 min into the reperfusion period. 4. Rapamycin (50 nmol/L) enhanced the phosphorylation of Akt kinase but did not affect the phosphorylation of ERK1/2 or eNOS at the end of reperfusion. The cardioprotective effect of rapamycin was blocked by the phosphatidylinositol 3-kinase (Akt) inhibitor LY294002 (15 nmol/L). 5. In conclusion, rapamycin mediates cardioprotection prior to ischaemia and after reperfusion. This protection may involve activation of the phosphatidylinositol 3-kinase pathway.


Assuntos
Cardiotônicos/farmacologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle , Sirolimo/farmacologia , Algoritmos , Animais , Creatina Quinase/metabolismo , Avaliação Pré-Clínica de Medicamentos , Hemodinâmica/efeitos dos fármacos , Técnicas In Vitro , L-Lactato Desidrogenase/metabolismo , Masculino , Infarto do Miocárdio/patologia , Tamanho do Órgão/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
15.
Plant Divers ; 43(6): 480-491, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35024517

RESUMO

Determining whether the high-latitude Bering land bridge (BLB) was ecologically suitable for the migration of mesothermal plants is significant for Holarctic phytogeographic inferences. Paleobotanical studies provide a critical source of data on the latitudinal positions of different plant lineages at different times, permitting assessment of the efficacy of the BLB for migration. Here we report exceptionally preserved fossils of Firmiana and Tilia endochrysea from the middle Miocene of South Korea. This represents a new reliable record of Firmiana and the first discovery of the T. endochrysea lineage in the fossil record of Asia. The occurrence of these fossils in South Korea indicates that the two lineages had a distribution that extended much farther north during the middle Miocene, but they were still geographically remote from the BLB. In light of the broader fossil record of Asia, our study shows that, in the middle Miocene, some mesothermal plants apparently inhabited the territory adjacent to the BLB and thus they were possibly capable of utilizing the BLB as a migratory corridor. Some other mesothermal plants, such as Firmiana and the T. endochrysea lineages, however, are restricted to more southern regions relative to the BLB based on current fossil evidence. These lineages may have been ecologically unable to traverse the BLB, which raises questions about the efficacy of the BLB as a universal exchange route for mesothermal plants between Asia and North America during the middle Miocene.

16.
World J Gastroenterol ; 27(32): 5404-5423, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34539141

RESUMO

BACKGROUND: Intestinal barrier breakdown, a frequent complication of intestinal ischemia-reperfusion (I/R) including dysfunction and the structure changes of the intestine, is characterized by a loss of tight junction and enhanced permeability of the intestinal barrier and increased mortality. To develop effective and novel therapeutics is important for the improvement of outcome of patients with intestinal barrier deterioration. Recombinant human angiopoietin-like protein 4 (rhANGPTL4) is reported to protect the blood-brain barrier when administered exogenously, and endogenous ANGPTL4 deficiency deteriorates radiation-induced intestinal injury. AIM: To identify whether rhANGPTL4 may protect intestinal barrier breakdown induced by I/R. METHODS: Intestinal I/R injury was elicited through clamping the superior mesenteric artery for 60 min followed by 240 min reperfusion. Intestinal epithelial (Caco-2) cells and human umbilical vein endothelial cells were challenged by hypoxia/ reoxygenation to mimic I/R in vitro. RESULTS: Indicators including fluorescein isothiocyanate-conjugated dextran (4 kilodaltons; FD-4) clearance, ratio of phosphorylated myosin light chain/total myosin light chain, myosin light chain kinase and loss of zonula occludens-1, claudin-2 and VE-cadherin were significantly increased after intestinal I/R or cell hypoxia/reoxygenation. rhANGPTL4 treatment significantly reversed these indicators, which were associated with inhibiting the inflammatory and oxidative cascade, excessive activation of cellular autophagy and apoptosis and improvement of survival rate. Similar results were observed in vitro when cells were challenged by hypoxia/reoxygenation, whereas rhANGPTL4 reversed the indicators close to normal level in Caco-2 cells and human umbilical vein endothelial cells significantly. CONCLUSION: rhANGPTL4 can function as a protective agent against intestinal injury induced by intestinal I/R and improve survival via maintenance of intestinal barrier structure and functions.


Assuntos
Proteína 4 Semelhante a Angiopoietina/farmacologia , Intestinos , Traumatismo por Reperfusão , Células CACO-2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Mucosa Intestinal , Proteínas Recombinantes/farmacologia , Traumatismo por Reperfusão/prevenção & controle
17.
Orthop Surg ; 13(6): 1818-1827, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34435459

RESUMO

OBJECTIVES: To explore factors affecting the efficacy of Bernese periacetabular osteotomy for the treatment of hip dysplasia. METHODS: A retrospective study was conducted on 44 patients with hip dysplasia who underwent Bernese periacetabular osteotomy with a modified Smith-Peterson approach between January 2017 and November 2019. Among them, 40 were women and four were men. The average age was 31.2 ± 9.4. Preoperative and postoperative imaging parameters were measured. The acetabular top tilt angle, lateral central edge angle, acetabular abduction angle, femoral head extrusion index, sphericity index of femoral head, Shenton line, Tonnis grade of osteoarthritis, joint congruency, p/a ratio, acetabular anteversion angle, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scale scores, and modified Harris hip score (MHHS) were observed. MHHS were divided into three clinically relevant categories: poor (<70 points), good (70-85 points), and excellent (86-91 points). Patient demographic data, as well as preoperative and postoperative radiographic parameters, were subjected to univariate logistic regression analysis. Multiple regression analysis was used to determine factors influencing postoperative MHHS. RESULTS: The follow-up time was 1.0-3.9 years after surgery, with an average of 1.6 years. By the last follow-up, MHHS increased from 70 points before surgery to 91 points after surgery (P < 0.001), WOMAC pain score decreased from 4 points before surgery to 0 points after surgery (P < 0.001). WOMAC functional score decreased (Preoperative: 18.0 [4.0]; Postoperative: 4.0 [0], P = 0.004). Six patients had sensory disturbance of the lateral femoral cutaneous nerve, four of which recovered completely during follow-up. No other complications related to surgical approach, osteotomy, acetabular displacement, acetabular fixation, and postoperative stage were found. There was no significant vascular, nerve, or visceral injuries in any of the patients. On multiple regression analysis, the probability of the postoperative modified Harris hip score of a hip joint with a preoperative lateral center edge angle ≥4.5° being classified as excellent was six times that of angles <4.5° (Exp[ß]: 6.249, 95% CI: 1.03-37.85, P = 0.046). Regression analysis of other factors found no significant correlation with postoperative functional scores. CONCLUSION: Overall functional scores post-PAO significantly improved, and pain symptoms were significantly reduced. Patients with a preoperative lateral center edge angle ≥4.5° had better joint function after surgery.


Assuntos
Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/cirurgia , Osteotomia/métodos , Recuperação de Função Fisiológica , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Radiografia , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
18.
Sci Adv ; 7(5)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33571113

RESUMO

The growth of the Tibetan Plateau throughout the past 66 million years has profoundly affected the Asian climate, but how this unparalleled orogenesis might have driven vegetation and plant diversity changes in eastern Asia is poorly understood. We approach this question by integrating modeling results and fossil data. We show that growth of north and northeastern Tibet affects vegetation and, crucially, plant diversity in eastern Asia by altering the monsoon system. This northern Tibetan orographic change induces a precipitation increase, especially in the dry (winter) season, resulting in a transition from deciduous broadleaf vegetation to evergreen broadleaf vegetation and plant diversity increases across southeastern Asia. Further quantifying the complexity of Tibetan orographic change is critical for understanding the finer details of Asian vegetation and plant diversity evolution.

19.
Zhonghua Gan Zang Bing Za Zhi ; 17(10): 745-9, 2009 Oct.
Artigo em Zh | MEDLINE | ID: mdl-19874689

RESUMO

OBJECTIVE: To evaluate the effects of ALT, HBsAg and HBV DNA at the baseline, 4 and 12 weeks after lamivudine treatment on the long term (104 weeks) response in e antigen-negative chronic hepatitis B patients. METHODS: 127 adult e antigen-negative chronic hepatitis B patients were enrolled in this study. All patients received treatment on LAM 100 mg/d for at least 104 weeks. The liver function, serum HBV markers and HBV viral load were regularly checked during the treatment. The effects of ALT, HBsAg and HBV DNA at the baseline, 4 and 12 weeks after lamivudine treatment on the response at 104 weeks were statistically analyzed. RESULTS: The proportion of patients with serum HBV DNA less than 1000 copies / ml at 104 weeks after LAM treatment was 50.0% and 86.8% in patients with baseline ALT less than 5 ULN and ALT is more than or equal to 5 ULN, respectively (P less than 0.01). In patients with baseline HBsAg less than 2000 COI and HBsAg is more than or equal to 2000 COI, the proportion of patients with serum HBsAg less than 500 COI at 104 weeks after LAM treatment was 19.1% and 17.5%, respectively (P more than 0.05). the HBsAg serological conversion rates were respectively 2.1% and 2.5% , respectively (P more than 0.05), the proportion of patients with serum HBV DNA less than 1000 copies/ml was 61.7% and 67.5%, respectively (P more than 0.05). In patients with baseline HBV DNA less than 10(6) copies/ml and HBV DNA is more than or equal to 10(6) copies/ml, the proportion of patients with HBV DNA less than 1000 copies/ml were statistically different at 4 weeks and 12 weeks after treatment, however, the proportion of patients with HBV DNA less than 1000 copies/ml at 104 weeks after LAM treatment was 62.7% and 67.1%, respectively (P more than 0.05). In patients with HBV DNA less than 1000 copies/ml and HBV DNA is more than or equal to 1000 copies/ml at 4 weeks after treatment, the proportion of patients with HBV DNA less than 1000 copies/ml at 104 weeks after LAM treatment was 70.7% and 60.9%, respectively (P more than 0.05). In patients with HBV DNA less than 1000 copies/ml and HBV DNA is more than or equal to 1000 copies/ml at 12 weeks after treatment, the proportion of patients with HBV DNA less than 1000 copies/ml at 104 weeks after treatment was 78.8% and 38.1%, respectively (P less than 0.01). CONCLUSION: e antigen negative chronic hepatitis B patients with baseline ALT is more than or equal to 5 ULN and HBV DNA less than 1000 copies/ml at 12 weeks after treatment have better virological response at 104 weeks after LAM treatment. The baseline HBsAg and HBV DNA load are associated with the virological response at 104 weeks after LAM treatment.


Assuntos
Antivirais/uso terapêutico , DNA Viral/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Administração Oral , Adulto , Idoso , Alanina Transaminase/sangue , Antivirais/farmacologia , Feminino , Seguimentos , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Lamivudina/farmacologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Carga Viral , Adulto Jovem
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(2): 399-401, 2009 Feb.
Artigo em Zh | MEDLINE | ID: mdl-19445213

RESUMO

The SERS spectra were measured from normal and the diabetic serum. In the diabetic serum, the band of amide II shifted to 1 585 cm(-1) and the relative intensity increased 14%, while the relative intensity of 593 cm(-1) which belongs to amide VI reduced 33%. For the protein side chain, the band at 1 368 cm(-1) assigned to the "buried" tryptophan shifted to 1 365 cm(-1) of the "exposed" and the relative intensity reduced 59%. The relative intensity of 635 cm(-1) assigned to the gauche conformation of the C-S decrased 15% and the band at 725 cm(-1) increased 58%. These indicate that the structure of the protein changed in the diabetic serum. The relative intensity at 1 449 cm(-1) assigned to the lipids characteristic increased 58%. The relative intensity of the glucide characteristic at 1 331, 1 099 and 740 cm(-1) increased 35%, 100% and 62%, respectively. So it is indicated that the content of lipids, glucide and protein increased in diabetic. These results may offer a powerful experimental basis for diabetes diagnosis and biochemistry mechanism study.

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