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1.
Environ Microbiol ; 24(7): 3063-3080, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35254697

RESUMO

The recently proposed order Candidatus Thermoprofundales, currently containing only one family-level lineage Marine Benthic Group-D (MBG-D), is distributed in global subsurface ecosystems and ecologically important, but its diversity, evolution and metabolism remain largely unknown. Here we described two novel family-level specialized lineages in Ca. Thermoprofundales, JdFR-43 and HyVt, which are restricted to specific biotopes (primarily in marine hydrothermal vents and occasionally in oil reservoirs and hot springs) in contrast to the cosmopolitan lineage MBG-D. The comparative genomics revealed that the specialized lineages have streamlined genomes, higher GC contents, enriched genes associated with nucleotide biosynthesis, ribosome biogenesis and DNA repair and additional thermostable aminopeptidases, enabling them to adapt to high-temperature habitats such as marine hydrothermal vents, deep subsurface oil reservoirs and hot springs. On the contrary, the unique metabolic traits of the cosmopolitan MBG-D, motility, glycolysis, butanoate metabolism, secondary metabolites production and additional genes for specific peptides and carbohydrates degradation potentially enhance its response to environmental change. Substrate preference is found for most MAGs across all lineages with the ability to utilize both polysaccharides (chitin and starch) and proteinaceous substances, whereas JdFR-43 members from oil reservoirs can only utilize proteins. These results expand the diversity of Ca. Thermoprofundales significantly and further improve our understandings of the adaptations of Ca. Thermoprofundales to various environments.


Assuntos
Fontes Termais , Fontes Hidrotermais , Archaea/genética , Ecossistema , Filogenia
2.
Zhonghua Nan Ke Xue ; 27(6): 506-512, 2021 Jun.
Artigo em Zh | MEDLINE | ID: mdl-34914289

RESUMO

OBJECTIVE: To investigate the correlation of the single nucleotide polymorphisms (SNP) rs1126772, rs117291487, rs11730582, rs142608941 and rs6813526 of the osteopontin (OPN) gene with the risk of asthenozoospermia (AZS). METHODS: We included 135 AZS patients in the AZS group and another 239 fertile men as normal controls. Using the SNaPshot technique, we genotyped the rs1126772, rs117291487, rs11730582, rs142608941 and rs6813526 polymorphisms of the OPN gene in all the subjects and analyzed the correlation of the five SNPs with AZS. RESULTS: The GA genotype and A allele of the OPN gene rs1126772 were found to be correlated with the risk of AZS (GA vs AA: OR = 0.55, 95% CI: 0.35-0.86, P = 0.009; A vs G: OR = 0.64, 95% CI: 0.46-0.89, P = 0.007), and so was the CT genotype and T allele at the RS11730582 locus (CT vs TT: OR = 0.526, 95% CI: 0.34-0.82, P = 0.009; T vs C: OR = 0.60, 95% CI: 0.44-0.83, P = 0.002). Haplotype analysis showed that the AATCT haplotype decreased the risk of AZS (AATCT: OR = 0.61, 95% CI: 0.42-0.88, P = 0.008) . CONCLUSIONS: The polymorphisms of the OPN gene RS1126772 and RS11730582 may reduce the risk of AZS.


Assuntos
Astenozoospermia/genética , Osteopontina , Polimorfismo de Nucleotídeo Único , Humanos , Masculino , Osteopontina/genética
3.
Environ Sci Technol ; 54(17): 10610-10620, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32786606

RESUMO

Microbial anaerobic alkane degradation is a key process in subsurface oil reservoirs and anoxic environments contaminated with petroleum, with a major impact on global carbon cycling. However, the thermophiles capable of water-insoluble paraffins (>C17) degradation under methanogenic conditions has remained understudied. Here, we established thermophilic (55 °C) n-paraffins-degrading (C21-C30) cultures from an oil reservoir. After over 900 days of incubation, the even-numbered n-paraffins were biodegraded to methane. The bacterial communities are dominated by a novel class-level lineage of actinobacteria, 'Candidatus Syntraliphaticia'. These 'Ca. Syntraliphaticia'-like metagenome-assembled genomes (MAGs) encode a complete alkylsuccinate synthases (ASS) gene operon, as well as hydrogenases and formate dehydrogenase, and several enzymes potentially involved in alkyl-CoA oxidation and the Wood-Ljungdahl pathway. Metatranscriptomic analysis suggests that n-paraffins are activated via fumarate addition reaction, and oxidized into carbon dioxide, hydrogen/formate and acetate by 'Ca. Syntraliphaticia', that could be further converted to methane by the abundant hydrogenotrophic and acetoclastic methanogens. We also found a divergent methyl-CoM reductase-like complex (MCR) and a canonical MCR in two MAGs representing 'Ca. Methanosuratus' (within candidate phylum Verstraetearchaeota), indicating the capability of methane and short-chain alkane metabolism in the oil reservoir. Ultimately, this result offers new insights into the degradability and the mechanisms of n-paraffins under methanogenic conditions at high temperatures.


Assuntos
Euryarchaeota , Parafina , Alcanos , Anaerobiose , Metano , Filogenia
4.
Chin J Cancer ; 32(11): 624-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23668927

RESUMO

Paraganglioma is a rare neuroendocrine neoplasm observed in patients of all ages, with an estimated incidence of 3/1,000,000 population. It has long been recognized that some cases are familial. The majority of these tumors are benign, and the only absolute criterion for malignancy is the presence of metastases at sites where chromaffin tissue is not usually found. Some tumors show gross local invasion and recurrence, which may indeed kill the patient, but this does not necessarily associate with metastatic potential. Here, we report a case of vertebral metastatic paraganglioma that occurred 19 months after the patient had undergone partial cystectomy for urinary bladder paraganglioma. We believe this to be a rarely reported bone metastasis of paraganglioma arising originally within the urinary bladder. In this report, we also provide a summary of the general characteristics of this disease, together with progress in diagnosis, treatment, and prognosis.


Assuntos
Paraganglioma , Neoplasias da Coluna Vertebral/secundário , Vértebras Torácicas , Neoplasias da Bexiga Urinária , Cromogranina A/metabolismo , Cistectomia , Feminino , Humanos , Pessoa de Meia-Idade , Paraganglioma/metabolismo , Paraganglioma/patologia , Paraganglioma/secundário , Paraganglioma/cirurgia , Fosfopiruvato Hidratase/metabolismo , Prognóstico , Cintilografia , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/cirurgia , Sinaptofisina/metabolismo , Tecnécio , Tomografia Computadorizada por Raios X , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia
5.
Curr Org Synth ; 19(7): 824-837, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35418286

RESUMO

AIMS: A simple, transition-metal-free C-S coupling protocol for the synthesis of aryl thioethers is reported. BACKGROUND: Sulfur-containing moieties are ubiquitous in pharmaceutical drugs and materials and therefore methods for their construction are of great importance. One approach entails the catalytic coupling of an aryl halohydrocarbon with a thiol, but the transition metal catalysts usually used are prone to poisoning by participating sulfur species and efficient catalysis is usually only achieved after complex ligand optimization. OBJECTIVE: New transition-metal-free approaches to the synthesis of C-S bonds are urgently need. METHODS: We screened the reaction conditions such as alkali, crown ether, solvent, temperature, etc., tested the compatibility of the reaction substrate, and analyzed the mechanism process. RESULTS: The optimized reaction conditions were determined to be 1.0 equiv of aryl halides and 1.2 equiv of thiols at 110 ℃ in toluene with K2CO3 (1.5 equiv) as a base, promoted by 10 mol% dicyclohexano-18-crown-6. Up to 33 examples of thioethers were synthesized under transitionmetal- free conditions in good to excellent yields. CONCLUSION: We have developed a simple and efficient method for the C-S cross-coupling of a wide variety of (hetero)aryl halides and thiols mediated by dicyclohexano-18-crown-6 and without the need for transition-metal catalyst. In addition, the preparation and gram-scale experiments of a variety of drug molecules further verify the practicability of our developed method.


Assuntos
Éteres de Coroa , Elementos de Transição , Carbonatos , Estrutura Molecular , Potássio , Compostos de Sulfidrila/química , Sulfetos/química , Enxofre/química
6.
AMB Express ; 11(1): 18, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33433783

RESUMO

Microbial degradation of recalcitrant alkanes under anaerobic conditions results in the accumulation of heavy oil fraction in oil reservoirs. Hydroxylation of alkanes is an important activation mechanism under anaerobic conditions, but the diversity and distribution of the responsible microorganisms in the subsurface environment are still unclear. The lack of functional gene polymerase chain reaction (PCR) primers and commercially available intermediate degradation chemical compounds are the major obstacles for this research. In this investigation, PCR primers for the ahyA gene (encoding alkane hydroxylase) were designed, evaluated, and improved based on the nucleotide sequences available. Using microbial genomic DNA extracted from oil-contaminated soil and production water samples of oil reservoirs, ahyA gene nucleotide sequences were amplified and retrieved successfully from production water sample Z3-25 of Shengli oilfield. Additionally, the signature biomarker of 2-acetylalkanoic acid was detected in both Shengli and Jiangsu oilfields. These results demonstrate that anaerobic hydroxylation is an active mechanism used by microorganisms to degrade alkanes in oxygen-depleted oil reservoirs. This finding expands the current knowledge of biochemical reactions about alkane degradation in subsurface ecosystems. In addition, the PCR primers designed and tested in this study serve as an effective molecular tool for detecting the microorganisms responsible for anaerobic hydroxylation of alkanes in this and other ecosystems.

7.
Front Cell Dev Biol ; 8: 600521, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330491

RESUMO

Podophyllotoxin (PPT) is a kind of lignans extracted from the roots and stems of the genus Podophyllum from the tiller family, and it has been widely used in the treatment of condyloma acuminatum, multiple superficial epithelioma in the clinics. However, PPT has been reported to be toxic and can cause liver defects and other organ poisoning. In addition, emerging evidences also indicate that PPT has reproductive toxicity and causes female reproduction disorders. In this study, we used fertilized oocytes and tried to explore the effects of PPT on the early embryonic development with the mouse model. The results showed that exposure to PPT had negative effects on the cleavage of zygotes. Further analysis indicated that PPT could disrupt the organization of spindle and chromosome arrangement at the metaphase of first cleavage. We also found that PPT exposure to the zygotes induced excessive reactive oxygen species (ROS), suggesting the occurrence of oxidative stress. Moreover, in the PPT-exposed embryos, there was positive γH2A.X and Annexin-V signals, indicating that PPT induced embryonic DNA damage and early apoptosis. In conclusion, our results suggested that PPT could affect spindle formation and chromosome alignment during the first cleavage of mouse embryos, and its exposure induced DNA damage-mediated oxidative stress which eventually led to embryonic apoptosis, indicating the toxic effects of PPT on the early embryo development.

8.
World J Gastroenterol ; 21(14): 4408-12, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25892895

RESUMO

Breast cancer can metastasize to other organs following initial treatment. Bones, liver, and the lung are the most common sites of breast cancer metastases. The digestive tract, on the other hand, is rarely involved. The incidence of mesorectal metastasis (a special category of rectal metastases) from breast cancer has not been described before. The case reported herein concerns a 68-year-old woman who underwent mastectomy. A pelvic mass with no symptoms was subsequently identified by computed tomography in the patient. We ultimately confirmed that this mass was a metastasis from breast cancer located in the mesorectum using surgical exploration and pathology results.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Neoplasias Retais/secundário , Idoso , Biomarcadores Tumorais/análise , Biópsia , Neoplasias da Mama/química , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/terapia , Quimioterapia Adjuvante , Feminino , Humanos , Imuno-Histoquímica , Mastectomia , Neoplasias Retais/química , Neoplasias Retais/cirurgia , Tomografia Computadorizada por Raios X
9.
CNS Neurosci Ther ; 20(1): 76-85, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24279586

RESUMO

AIMS: Gene therapy targeting the SNCA gene yields promising results in the treatment of Parkinson's disease (PD). The most challenging issue of the RNAi gene therapy strategy is maintaining efficient delivery without inducing significant toxicity and other adverse effects. This study aimed to characterize polyethylene glycol-polyethyleneimine as a vector for alpha-synuclein siRNA delivery to PC12 cells for Parkinson's disease. METHODS: The characteristics of PEG-PEI/siSNCA were analyzed via gel retardation assay and assessments of particle size and zeta potential. MTT cytotoxicity assay and flow cytometry were used to detect cytotoxicity and transfection efficiency in PC12 cells. Confocal laser scanning microscopy was employed to examine the intracellular distribution of PEG-PEI/FITC-siSNCA after cellular uptake. RT-PCR and western blotting were used to measure SNCA expression. The MTT cytotoxicity assay was used to study the effect of PEG-PEI/siSNCA on cell viability. The protective effect of PEG-PEI/siSNCA on MPP+-induced apoptosis in PC12 cells was examined via flow cytometry and Hoechst staining. RESULTS: PEG-PEI/siSNCA complexes were well-developed; they exhibited appropriate particle sizes and zeta potentials at a mass ratio of 5:1. In vitro, PEG-PEI/siSNCA was associated with low cytotoxicity and high transfection efficiency. Complexes were capable of successfully delivering siSNCA into PC12 cells and releasing it from the endosome. Furthermore, PEG-PEI/siSNCA could effectively suppress SNCA mRNA expression and protected cells from death via apoptosis induced by MPP(+) . CONCLUSIONS: Our results demonstrate that PEG-PEI performs well as a vector for alpha-synuclein siRNA delivery into PC12 cells. Additionally, PEG-PEI/siSNCA complexes were suggested to be able to protect cells from death via apoptosis induced by MPP(+) . These findings suggest that PEG-PEI/siSNCA nanoparticles exhibit remarkable potential as a gene delivery system for Parkinson's disease.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética , Polietilenoglicóis , Polietilenoimina/análogos & derivados , RNA Interferente Pequeno/administração & dosagem , alfa-Sinucleína/genética , Animais , Apoptose , Forma do Núcleo Celular , Sobrevivência Celular , Regulação para Baixo , Endossomos/fisiologia , Espaço Intracelular/metabolismo , Neurotoxinas/toxicidade , Células PC12 , Doença de Parkinson/terapia , Tamanho da Partícula , Polietilenoglicóis/toxicidade , Polietilenoimina/toxicidade , RNA Mensageiro/metabolismo , Ratos , Sais de Tetrazólio/toxicidade , Tiazóis/toxicidade , alfa-Sinucleína/metabolismo
10.
Artigo em Zh | MEDLINE | ID: mdl-19957650

RESUMO

OBJECTIVE: To observe the histopathological finding of bone remodeling in rabbit sinusitis model at different time and the tendency, and to discuss the effect of bone in the pathogenesis of sinusitis. METHODS: First, the rabbit sinusitis model was made, then the experimental animals were divided into 3 groups according to the time of infection. There were 8 rabbits in each experimental group, and 4 rabbits in the control group. The sinus specimen were collected, embedded and stained. The bone in the inoculating side and noninoculating side was scored, and the bone in inoculating side was evaluated quantitatively and semiquantitatively. The parameters included the thickness of mucosa, mucoperiosteum, the density of osteoblast, the amount of osteoclast. RESULTS: The average bone score in the inoculating side was 2.250, 2.875, 2.875; in the noninoculating side was 1.625, 2.250, 2.500. Between group A and the control group, the difference of all three parameters had statistical significance. Between group B and group A, the difference of the thickness of mucosa and the density of osteoblast had statistical significance. Between group C and group B, none of the three parameters had statistical significance. CONCLUSIONS: Bacterial sinusitis can lead to bone remodeling, obvious bone destroy can occur at the early phase, then the bone proliferation follows. These results demonstrate that bone remodeling is one of the basic histopathological characters of CRS and might be the reason to lead CRS to a constant and chronic process of inflammation.


Assuntos
Remodelação Óssea , Sinusite/patologia , Animais , Modelos Animais de Doenças , Inflamação , Osso Nasal/patologia , Coelhos
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(3): 447-8, 2008 Mar.
Artigo em Zh | MEDLINE | ID: mdl-18359710

RESUMO

OBJECTIVE: To investigate the clinical heterogeneity of movement disorder in Parkinson's disease (PD). METHODS: Ninety-eight PD patients (68 males and 30 females) were divided into tremor-dominant PD (n=23), mixed subtype PD (n=29) and postural instability and gait disorder (PIGD)-dominant PD (n=46) groups, and the clinical heterogeneity of the movement function of the patients was compared. RESULTS: The initial symptom of tremor-predominant PD was tremor, but patients with PIGD-dominant PD had rigidity and gait disorder as the initial symptoms, commonly compromising the left limb. The amended Hoehn-Yahr stage of tremor-dominant PD was significantly lower than that of the PIGD-dominant PD, while the score of Mini-Mental State Examination (MMSE) was significantly higher in the former. No statistical differences were found in the gender, course of disease and family history between the patients with different subtypes of PD. CONCLUSION: There are significant differences in the initial and typical symptoms between tremor-dominant PD and PIGD-dominant PD.


Assuntos
Transtornos Neurológicos da Marcha/patologia , Transtornos dos Movimentos/patologia , Doença de Parkinson/patologia , Idoso , Feminino , Transtornos Neurológicos da Marcha/classificação , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/classificação , Transtornos dos Movimentos/fisiopatologia , Doença de Parkinson/classificação , Doença de Parkinson/fisiopatologia , Equilíbrio Postural , Tremor/patologia , Tremor/fisiopatologia
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