RESUMEN
Unlike many other aminoacyl-tRNA synthetases, alanyl-tRNA synthetase (AlaRS) retains a conserved prototype structure throughout biology. While Caenorhabditis elegans cytoplasmic AlaRS (CeAlaRSc) retains the prototype structure, its mitochondrial counterpart (CeAlaRSm) contains only a residual C-terminal domain (C-Ala). We demonstrated herein that the C-Ala domain from CeAlaRSc robustly binds both tRNA and DNA. It bound different tRNAs but preferred tRNAAla. Deletion of this domain from CeAlaRSc sharply reduced its aminoacylation activity, while fusion of this domain to CeAlaRSm selectively and distinctly enhanced its aminoacylation activity toward the elbow-containing (or L-shaped) tRNAAla. Phylogenetic analysis showed that CeAlaRSm once possessed the C-Ala domain but later lost most of it during evolution, perhaps in response to the deletion of the T-arm (part of the elbow) from its cognate tRNA. This study underscores the evolutionary gain of C-Ala for docking AlaRS to the L-shaped tRNAAla.
Asunto(s)
Alanina-ARNt Ligasa , Aminoacil-ARNt Sintetasas , Alanina-ARNt Ligasa/genética , Aminoacil-ARNt Sintetasas/genética , Aminoacilación , Filogenia , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , ARN de Transferencia de Alanina/genéticaRESUMEN
Pseudomonas sp. A46 was first isolated from mercury-contaminated groundwater in Taiwan. This study is the first to report the draft whole-genome sequence of Pseudomonas sp. A46. Its genome consists of 126 contigs, with a total length of 6,782,516 bp and a GC content of 64.7%. Phylogenetic analysis based on 16 S rRNA gene sequences revealed that Pseudomonas sp. A46 is closely related to Pseudomonas citronellolis. Assessment of the draft genome sequence revealed that Pseudomonas sp. A46 harbors sets of genes conferring resistance to heavy metals, such as mercury, zinc, lead, copper, cadmium, chromate, and arsenate. These identified genes enable this bacterium to tolerate heavy metal stress.
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Mercurio , Metales Pesados , Arseniatos , Cadmio , Cromatos , Cobre , Metales Pesados/análisis , Filogenia , Pseudomonas/genética , Aguas Residuales , ZincRESUMEN
Long intergenic noncoding RNAs (lincRNAs) play a vital role in the occurrence and progression of cancer. The mechanism of lincRNAs in colorectal cancer (CRC) has not been fully elucidated. In this context, an integrated comparative long noncoding RNA (lncRNA) microarray technology was used to determine the expression profile of lncRNAs in CRC. The roles of LINC00908 are unclear. We found that LINC00908 was significantly upregulated in CRC. Inhibition of LINC00908 resulted in reduced cell proliferation and G1 cell cycle arrest, which was mediated by cyclin D1, cyclin-dependent kinase 4, and phosphorylated retinoblastoma. Moreover, inhibition of LINC00908-induced apoptosis through the intrinsic apoptosis signaling pathway, as shown by the activation of caspase-9 and caspase-3. Mechanistically, miR-143-3p directly bound to LINC00908. miR-143-3p expression was negatively correlated with LINC00908 expression in CRC tissue. Functional experiments revealed opposing roles for miR-143-3p and LINC00908, suggesting that LINC00908 negatively regulates miR-143-3p. Mechanistically, miR-143-3p directly targets LINC00908. The KLF5 inhibitor ML264 affected proliferation and apoptosis, indicating that LINC00908 may act as a competing endogenous RNA to facilitate the expression of the miR-143-3p target gene KLF5. Thus, LINC00908 has an important proliferative and antiapoptotic role in CRC by regulating the cell cycle and intrinsic apoptosis. LINC00908 could be a potential biomarker and a new therapeutic target for CRC.
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Apoptosis/genética , Proliferación Celular/genética , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica/genética , Factores de Transcripción de Tipo Kruppel/genética , ARN Largo no Codificante/genética , Línea Celular , Línea Celular Tumoral , Movimiento Celular/genética , Neoplasias Colorrectales/patología , Puntos de Control de la Fase G1 del Ciclo Celular/genética , Células HCT116 , Humanos , Transducción de Señal/genética , Regulación hacia Arriba/genéticaRESUMEN
BACKGROUND: The medical consortium is an intensive and disease-specific association that integrates tertiary public hospitals and medical examination centers in China. We aimed to evaluate the feasibility of the medical consortium for screening upper gastrointestinal (GI) cancers (MCSC) by magnetically controlled capsule gastroscopy (MCCG). METHODS: 6627 asymptomatic subjects underwent MCCG as part of health check-ups in the MCSC between March and November 2018.âRelevant clinical data were collected and analyzed. RESULTS: The MCSC detected 32 patients with upper GI cancer (0.48â%) confirmed by pathology. The detection rate of early gastric cancer was 16.67â% (4â/24). Gastric polyps, ulcers, and submucosal tumors were found in 15.54â%, 3.76â%, and 3.17â% of subjects, respectively. The whole GI preparation and operation process were well tolerated. CONCLUSIONS: The MCSC was a feasible model for upper GI cancer screening, especially for asymptomatic subjects. Further prospective studies with better operational quality control are warranted.
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Endoscopía Capsular , Neoplasias Gástricas , Detección Precoz del Cáncer , Estudios de Factibilidad , Gastroscopía , Humanos , Estudios Prospectivos , Neoplasias Gástricas/diagnósticoRESUMEN
Background: Endoscopic submucosal excavation (ESE), endoscopic full-thickness resection (EFTR) and submucosal tunneling endoscopic resection (STER) have been widely applied to upper gastrointestinal submucosal tumors (SMTs) originating from the muscularis propria (MP) layer in recent years. But until now, there are few studies that comparing the efficacy and safety of three endoscopic therapy methods.Method: From January 2013 to August 2018, a total of 218 patients with SMTs who underwent ESE, EFTR or STER were enrolled in this retrospective study. Clinicopathological characteristics, endoscopic features, complication and follow-up data were analyzed.Result: There were 114 patients underwent ESE, 61 underwent EFTR and 43 underwent STER, respectively. The en bloc and complete resection rates in STER group (83.7% and 90.0%) were significantly lower and postoperative complication rate (62.8%) was significantly higher than those of the other 2 methods. Furthermore, for lesions <40 mm, no significant differences were found in the en bloc rate, complete rate and postoperative complication rate among 3 methods. The perforation rate decreased in the order of EFTR (100%), ESE (23.7%), STER (7.0%). The median number of clips, fasting time and hospital stay were lowest in ESE group (5, 2 days, and 7 days). And the cost was highest in EFTR group ($4993.1). There were no differences in the bleeding and recurrence rates among three groups.Conclusion: For SMTs <40 mm, the efficacy among 3 ER methods are comparative. The choice of ER methods mainly based on the comprehensive consideration of lesion size, location, growth pattern and clinical experience of endoscopists. For benign SMTs ≥40 mm in stomach, ESE and EFTR becomes alternative choices.
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Resección Endoscópica de la Mucosa , Neoplasias Esofágicas , Esofagoscopía , Gastroscopía , Complicaciones Intraoperatorias , Complicaciones Posoperatorias , Neoplasias Gástricas , China/epidemiología , Resección Endoscópica de la Mucosa/efectos adversos , Resección Endoscópica de la Mucosa/clasificación , Resección Endoscópica de la Mucosa/métodos , Mucosa Esofágica/patología , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Esofagoscopía/efectos adversos , Esofagoscopía/métodos , Femenino , Mucosa Gástrica/patología , Gastroscopía/efectos adversos , Gastroscopía/métodos , Humanos , Complicaciones Intraoperatorias/epidemiología , Complicaciones Intraoperatorias/etiología , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugíaRESUMEN
Diabetes mellitus (DM) comprises a group of metabolic diseases characterized by insulin deficiency or resistance and hyperglycemia. We previously reported the presence of abnormal differentiation of small intestinal epithelial cells (IECs) in diabetic mice, but the exact mechanism of this phenomenon has not been thoroughly elucidated to date. In this study, we found that H19 was markedly upregulated in IECs of DM mice. H19 knockdown significantly inhibited abnormal differentiation of IECs in DM mice. Bioinformatics analysis identified miR-141-3p as a candidate for H19. Based on luciferase reporter assays, we found that miR-141-3p directly targeted H19. Luciferase reporter assays also showed that miR-141-3p could directly target ß-catenin. Furthermore, H19 might act as an endogenous "sponge" by competing for miR-141-3p binding to regulate miRNA targets in vitro and in vivo. In summary, our findings provide the first evidence supporting the role of H19 in IECs of DM mice, and miR-141-3p targets not only protein-coding genes but also the lncRNA H19.
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Diabetes Mellitus/genética , MicroARNs/genética , ARN Largo no Codificante/genética , beta Catenina/genética , Animales , Diferenciación Celular/genética , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patología , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Regulación del Desarrollo de la Expresión Génica/genética , Técnicas de Silenciamiento del Gen , Humanos , Hiperglucemia/genética , Hiperglucemia/patología , Resistencia a la Insulina/genética , Intestino Delgado/metabolismo , Intestino Delgado/patología , Ratones , Ratones Endogámicos NOD , Unión ProteicaRESUMEN
The causes of high biological diversity in biodiversity hotspots have long been a major subject of study in conservation biology. To investigate this matter, we conducted a phylogeographic study of five Drosophila (Diptera: Drosophilidae) species from East and Southeast Asia: Drosophila albomicans Duda, D. formosana Duda, D. immigrans Sturtevant, D. melanogaster Meigen, and D. simulans Sturtevant. We collected 185 samples from 28 localities in eight countries. From each collected individual, we sequenced the autosomal extra sex comb gene (esc) and seven mitochondrial genes, including nicotinamide adenine dinucleotide hydrate-reductase dehydrogenase subunit 4 (ND4), ND4L, tRNA-His, tRNA-Pro, tRNA-Thr, partial ND5, and partial ND6. Phylogenetic analyses using maximum- likelihood and Bayesian methods revealed interesting population structure and identified the existence of two distinct D. formosana lineages (Southeast Asian and Taiwanese populations). Genetic differentiation among groups of D. immigrans suggests the possibility of endemic speciation in Taiwan. In contrast, D. melanogaster remained one extensively large population throughout East and Southeast Asia, including nearby islets. A molecular clock was used to estimate divergence times, which were compared with past geographical events to infer evolutionary scenarios. Our findings suggest that interglacial periods may have caused population isolation, thus enhancing population differentiation more strongly for some of the Drosophila species. The population structure of each Drosophila species in East and Southeast Asia has been influenced by past geographic events.
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Drosophila/genética , Variación Genética , Animales , Asia , Teorema de Bayes , Biodiversidad , Evolución Biológica , Drosophila/clasificación , Femenino , Especiación Genética , Masculino , Filogenia , Filogeografía , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: Gastric phytobezoars (GPBs) are very common in northern China. Combined therapy involving carbonated beverage consumption and endoscopic lithotripsy has been shown to be effective and safe. Existing studies on this subject are often case reports highlighting the successful dissolution of phytobezoars through Coca-Cola consumption. Consequently, large-scale prospective investigations in this domain remain scarce. Therefore, we conducted a randomized controlled trial to examine the effects of Coca-Cola consumption on GPBs. AIM: To evaluate the impact of Coca-Cola on GPBs, including the dissolution rate, medical expenses, ulcer rate, and operation time. METHODS: A total of 160 consecutive patients diagnosed with GPBs were allocated into two groups (a control group and an intervention group) through computer-generated randomization. Patients in the intervention group received a Coca-Cola-based regimen (Coca-Cola 2000-4000 mL per day for 7 d), while those in the control group underwent emergency fragmentation. RESULTS: Complete dissolution of GPBs was achieved in 100% of the patients in the intervention group. The disparity in expenses between the control group and intervention group (t = 25.791, P = 0.000) was statistically significant, and the difference in gastric ulcer occurrence between the control group and intervention group (χ2 = 6.181, P = 0.013) was also statistically significant. CONCLUSION: Timely ingestion of Coca-Cola yields significant benefits, including a complete dissolution rate of 100%, a low incidence of gastric ulcers, no need for fragmentation and reduced expenses.
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A practical way to reduce the cost of surveying single-nucleotide polymorphism (SNP) in a large number of individuals is to measure the allele frequencies in pooled DNA samples. Pyrosequencing(TM) has been frequently used for this application because signals generated by this approach are proportional to the amount of DNA templates. The Pyrosequencing(TM) pyrogram is determined by the dispensing order of dNTPs, which is usually designed based on the known SNPs to avoid asynchronistic extensions of heterozygous sequences. Therefore, utilizing the pyrogram signals to identify de novo SNPs in DNA pools has never been undertook. Here, in this study we developed an algorithm to address this issue. With the sequence and pyrogram of the wild-type allele known in advance, we could use the pyrogram obtained from the pooled DNA sample to predict the sequence of the unknown mutant allele (de novo SNP) and estimate its allele frequency. Both computational simulation and experimental Pyrosequencing(TM) test results suggested that our method performs well. The web interface of our method is available at http://life.nctu.edu.tw/â¼yslin/PSM/.
Asunto(s)
Algoritmos , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN/métodos , Simulación por Computador , Difosfatos/análisis , Frecuencia de los GenesRESUMEN
We aimed to investigate the safety and efficacy of endoscopic resection for the treatment of gastric gastrointestinal stromal tumors (GISTs) under single-channel gastroscopy and double-channel gastroscopy. We identified 154 patients with GISTs of the stomach who underwent endoscopic resection and were retrospectively analyzed at our hospital between May 2016 and March 2020, including 49 patients by single-channel gastroscopy and 105 patients by double-channel gastroscopy. We observed the clinical efficacy, complications, and safety of endoscopic resection of gastric GISTs, and the data were evaluated retrospectively. All patients underwent endoscopic resection successfully, without conversion to open surgery. In the single-channel gastroscopy group, 7 patients had lesions in the gastric cardia, 17 in the gastric fundus, 20 in the gastric corpus, and 5 in the gastric antrum. In the double-channel gastroscopy group, 13 patients had lesions in the gastric cardia, 34 in the gastric fundus, 46 in the gastric body, 10 in the gastric antrum, 1 in the pylorus, and 1 in the gastric angular incisure. The double-channel gastroscopy group had a shorter operation time than the single-channel gastroscopy group (59.9 ± 34.9 minutes vs 74.8 ± 26.7 minutes; P = .009 and P < .01, respectively), while they also had a lower perforation rate than the single-channel gastroscopy group (34.3% vs 51.0%; P = .048 and P < .05, respectively). No residual or recurrent lesions were discovered in any patients by gastroscopy reexamination. Both single-channel gastroscopy and double-channel gastroscopy can provide safe, effective, feasible endoscopic resection. However, double-channel gastroscopy has some distinct advantages in endoscopic resection.
Asunto(s)
Tumores del Estroma Gastrointestinal , Neoplasias Gástricas , Tumores del Estroma Gastrointestinal/cirugía , Gastroscopía , Humanos , Estudios Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Resultado del TratamientoRESUMEN
Resveratrol, a naturally occurring dietary compound with chemopreventive properties has been reported to trigger a variety of cancer cell types to apoptosis. Whether resveratrol shows any activity on human nasopharyngeal carcinoma (NPC) cells remained to be determined. The aim of this study was to investigate the effect and mechanism of resveratrol on human NPC cells. Treatment of resveratrol resulted in significant decrease in cell viability of NPC cell lines in a dose- and time-dependent manner. A dose-dependent apoptotic cell death was also measured by flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled resveratrol treatment resulted in a significant loss of mitochondrial transmembrane potential, release of cytochrome c, enhanced expression of Fas ligand (FasL), and suppression of glucose-regulated protein 78 kDa (GRP78). These were followed by activation of caspases-9, -8, -4, and -3, subsequently leading to DNA fragmentation and cell apoptosis. Furthermore, up-regulation of proapoptotic Bax and down-regulation of antiapoptotic Bcl-2 protein were also observed. Taken together, resveratrol induces apoptosis in human NPC cells through regulation of multiple apoptotic pathways, including death receptor, mitochondria, and endoplasmic reticulum (ER) stress. Resveratrol can be developed as an effective compound for human NPC treatment.
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Apoptosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Estilbenos/farmacología , Carcinoma , Caspasas/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Chaperón BiP del Retículo Endoplásmico , Proteína Ligando Fas/genética , Proteína Ligando Fas/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Modelos Biológicos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/enzimología , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Resveratrol , Factor de Transcripción CHOP/genética , Factor de Transcripción CHOP/metabolismoRESUMEN
BACKGROUND: Liver transplantation (LT) is the most effective treatment strategy for advanced liver diseases. With the increasing survival rate and prolonged survival time, the postoperative long-term complications of LT recipients are becoming an important concern. Among them, the newly developed cancer after LT is the second complication and cause of LT-related death after cardiovascular disease. At present, few papers have reported multiple primary carcinomas (MPCs) after LT. Herein, we retrospectively analyzed an MPC case with gastric cancer and lung cancer after LT. CASE SUMMARY: Herein, we retrospectively analyzed an MPC case with de novo gastric cancer and lung cancer after LT with no obvious complaints. Forty-one months after LT, the patient underwent radical distal gastrectomy (Billroth II) for intramucosal signet ring cell carcinoma, and then thoracoscopic wedge resection of the right lower lobe of the right lung and localized lymph node dissection 2 mo later. Therefore, paying attention to follow-up in LT recipients with early detection and intervention of de novo MPCs is the key to improving the survival rate and quality of life of LT recipients. CONCLUSION: De novo MPCs after LT are rare, and the prognosis is poorer. However, early detection and related intervention can significantly improve the prognosis of patients. Therefore, we recommend that liver transplant recipients should be followed and screened for newly developed malignant tumors to improve the survival rate and quality of life.
RESUMEN
The yeast Saccharomyces cerevisiae proliferates rapidly in glucose-containing media. As glucose is getting depleted, yeast cells enter the transition from fermentative to nonfermentative metabolism, known as the diauxic shift, which is associated with major changes in gene expression. To understand the expression evolution of genes involved in the diauxic shift and in nonfermentative metabolism within species, a laboratory strain (BY), a wild strain (RM), and a clinical isolate (YJM) were used in this study. Our data showed that the RM strain enters into the diauxic shift approximately 1 h earlier than the BY strain with an earlier, higher induction of many key transcription factors (TFs) involved in the diauxic shift. Our sequence data revealed sequence variations between BY and RM in both coding and promoter regions of the majority of these TFs. The key TF Cat8p, a zinc-finger cluster protein, is required for the expression of many genes in gluconeogenesis under nonfermentative growth, and its derepression is mediated by deactivation of Mig1p. Our kinetic study of CAT8 expression revealed that CAT8 induction corresponded to the timing of glucose depletion in both BY and RM and CAT8 was induced up to 50- to 90-folds in RM, whereas only 20- to 30-folds in BY. In order to decipher the relative importance of cis- and trans-variations in expression divergence in the gluconeogenic pathway during the diauxic shift, we studied the expression levels of MIG1, CAT8, and their downstream target genes in the cocultures and in the hybrid diploids of BY-RM, BY-YJM, and RM-YJM and in strains with swapped promoters. Our data showed that the differences between BY and RM in the expression of MIG1, the upstream regulator of CAT8, were affected mainly by changes in cis-elements, though also by changes in trans-acting factors, whereas those of CAT8 and its downstream target genes were predominantly affected by changes in trans-acting factors.
Asunto(s)
Evolución Molecular , Regulación Fúngica de la Expresión Génica , Gluconeogénesis , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Alelos , ADN de Hongos , Diploidia , Fermentación/genética , Perfilación de la Expresión Génica , Glucosa/metabolismo , Hibridación Genética , Regiones Promotoras Genéticas , Saccharomyces cerevisiae/crecimiento & desarrollo , Proteínas de Saccharomyces cerevisiae/genética , Análisis de Secuencia de ADN , Especificidad de la EspecieRESUMEN
Long noncoding RNAs (lncRNAs) are important regulators of the biological functions and underlying molecular mechanisms of colorectal cancer (CRC). However, the role of the lncRNA ZEB1-AS1 in CRC is not thoroughly understood. In this study, we found that ZEB1-AS1 was markedly upregulated in CRC. ZEB1-AS1 knockdown significantly suppressed CRC cell proliferation and induced apoptosis, whereas enhanced expression of ZEB1-AS1 had the opposite effect. Bioinformatics analysis identified miR-181a-5p as a candidate target of ZEB1-AS1. Moreover, we found an inverse correlation between ZEB1-AS1 and miR-181a-5p expression in CRC tissue. Inhibition of miR-181a-5p significantly upregulated ZEB1-AS1, whereas overexpression of miR-181a-5p had the opposite effect, suggesting that ZEB1-AS1 is negatively regulated by miR-181a-5p. Using luciferase reporter and RIP assays, we found that miR-181a-5p directly targets ZEB1-AS1. Importantly, ZEB1-AS1 may act as an endogenous 'sponge' to regulate miRNA targets by competing for miR-181a-5p binding. In summary, our findings provide the evidence supporting the role of ZEB1-AS1 as an oncogene in CRC. Our study also demonstrates that miR-181a-5p targets not only protein-coding genes but also the lncRNA ZEB1-AS1.
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Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Vía de Señalización Wnt , Apoptosis/genética , Secuencia de Bases , Línea Celular Tumoral , Proliferación Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , ARN Largo no Codificante/genética , Regulación hacia Arriba/genética , Vía de Señalización Wnt/genéticaRESUMEN
The complete mitochondrial genome sequence of Microhyla fissipes from Yi-Lan, Taiwan was determined through Sanger sequencing. The total length was 16,729 nucleotide base pairs. The genome included distinctive 37 genes, one light-strand replication origin and one control region. Regardless indels the non-coding genes were more conserved than the coding genes within Microhyla, as well as in Kaloula. The abnormal high differences in ND5 (0.2316) and ND6 (0.2406) between Taiwan and China samples is interesting for further studies.
RESUMEN
BACKGROUND: The higher-level phylogeny of placental mammals has long been a phylogenetic Gordian knot, with disagreement about both the precise contents of, and relationships between, the extant orders. A recent MRP supertree that favoured 'outdated' hypotheses (notably, monophyly of both Artiodactyla and Lipotyphla) has been heavily criticised for including low-quality and redundant data. We apply a stringent data selection protocol designed to minimise these problems to a much-expanded data set of morphological, molecular and combined source trees, to produce a supertree that includes every family of extant placental mammals. RESULTS: The supertree is well-resolved and supports both polyphyly of Lipotyphla and paraphyly of Artiodactyla with respect to Cetacea. The existence of four 'superorders'--Afrotheria, Xenarthra, Laurasiatheria and Euarchontoglires--is also supported. The topology is highly congruent with recent (molecular) phylogenetic analyses of placental mammals, but is considerably more comprehensive, being the first phylogeny to include all 113 extant families without making a priori assumptions of suprafamilial monophyly. Subsidiary analyses reveal that the data selection protocol played a key role in the major changes relative to a previously published higher-level supertree of placentals. CONCLUSION: The supertree should provide a useful framework for hypothesis testing in phylogenetic comparative biology, and supports the idea that biogeography has played a crucial role in the evolution of placental mammals. Our results demonstrate the importance of minimising poor and redundant data when constructing supertrees.
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Evolución Molecular , Mamíferos/clasificación , Placenta/metabolismo , Animales , Evolución Biológica , Humanos , Modelos Estadísticos , Filogenia , Especificidad de la EspecieRESUMEN
Osajin is a prenylated isoflavone showing antitumor activity in different tumor cell lines. The underlying mechanism of osajin-induced cancer cell death is not clearly understood. In the present study, the mechanisms of osajin-induced cell death of human nasopharyngeal carcinoma (NPC) cells were explored. Osajin was found to significantly induce apoptosis of NPC cells in a dose- and time-dependent manner. Multiple molecular effects were observed during osajin treatment including a significant loss of mitochondrial transmembrane potential, release of cytochrome c into the cytosol, enhanced expression of Fas ligand (FasL), suppression of glucose-regulated protein 78 kDa (GRP78), and activation of caspases-9, -8, -4 and -3. In addition, up-regulation of proapoptotic Bax protein and down-regulation of antiapoptotic Bcl-2 protein were also observed. Taken together, osajin induces apoptosis in human NPC cells through multiple apoptotic pathways, including the extrinsic death receptor pathway, and intrinsic pathways relying on mitochondria and endoplasmic reticulum stress. Thus, osajin could be developed as a new effective and chemopreventive compound for human NPC.
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Apoptosis , Isoflavonas/farmacología , Neoplasias Nasofaríngeas/patología , Extractos Vegetales/farmacología , Línea Celular Tumoral , Chaperón BiP del Retículo Endoplásmico , Humanos , Potenciales de la Membrana/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Neoplasias Nasofaríngeas/metabolismoAsunto(s)
Etanol/farmacología , Virus de la Hepatitis B/fisiología , Hepatitis B/virología , Replicación Viral/efectos de los fármacos , Animales , ADN Viral/sangre , Hepatitis B/metabolismo , Virus de la Hepatitis B/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Integración Viral/efectos de los fármacosRESUMEN
This study provides an extensive set of mitochondrial cytochrome b sequences for the salamander genus Pseudobranchus of the southeastern United States. These sequences were analysed by multiple phylogenetic methods that support a single set of major phylogeographic divisions for its two corroborated species (P. axanthus and P. striatus). These phylogeographic divisions overlap with the geographic breakpoints of other freshwater and terrestrial taxa in this region. Collectively, these overlapping patterns highlight the Central Highland and Tifton/Vidalia uplands as a significant barrier to Atlantic vs. Gulf coast groups, while reconfirming the phylogeographic significance of the Altamaha and Apalachicola river drainages. Despite their distinct phylogeographic split, P. striatus from west and east of these uplands are not currently recognizable as separate species according to the concordance principles for species definition.