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1.
Appl Environ Microbiol ; 83(13)2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28432102

RESUMO

Species in the extremely thermophilic genus Caldicellulosiruptor can degrade unpretreated plant biomass through the action of multimodular glycoside hydrolases. To date, most focus with these bacteria has been on hydrolysis of glucans and xylans, while the biodegradation mechanism for arabinose-based polysaccharides remains unclear. Here, putative α-l-arabinofuranosidases (AbFs) were identified in Caldicellulosiruptor species by homology to less-thermophilic versions of these enzymes. From this screen, an extracellular XynF was determined to be a key factor in hydrolyzing α-1,2-, α-1,3-, and α-1,5-l-arabinofuranosyl residues of arabinose-based polysaccharides. Combined with a GH11 xylanase (XynA), XynF increased arabinoxylan hydrolysis more than 6-fold compared to the level seen with XynA alone, likely the result of XynF removing arabinofuranosyl side chains to generate linear xylans that were readily degraded. A second AbF, the intracellular AbF51, preferentially cleaved the α-1,5-l-arabinofuranosyl glycoside bonds within sugar beet arabinan. ß-Xylosidases, such as GH39 Xyl39B, facilitated the hydrolysis of arabinofuranosyl residues at the nonreducing terminus of the arabinose-branched xylo-oligosaccharides by AbF51. These results demonstrate the separate but complementary contributions of extracellular XynF and cytosolic AbF51 in processing the bioconversion of arabinose-containing oligosaccharides to fermentable monosaccharides.IMPORTANCE Degradation of hemicellulose, due to its complex chemical structure, presents a major challenge during bioconversion of lignocellulosic biomass to biobased fuels and chemicals. Degradation of arabinose-containing polysaccharides, in particular, can be a key bottleneck in this process. Among Caldicellulosiruptor species, the multimodular arabinofuranosidase XynF is present in only selected members of this genus. This enzyme exhibited high hydrolysis activity, broad specificity, and strong synergism with other hemicellulases acting on arabino-polysaccharides. An intracellular arabinofuranosidase, AbF51, occurs in all Caldicellulosiruptor species and, in conjunction with xylosidases, processes the bioconversion of arabinose-branched oligosaccharides to fermentable monosaccharides. Taken together, the data suggest that plant biomass degradation in Caldicellulosiruptor species involves extracellular XynF that acts synergistically with other hemicellulases to digest arabino-polysaccharides that are subsequently transported and degraded further by intracellular AbF51 to produce short-chain arabino sugars.


Assuntos
Arabinose/metabolismo , Proteínas de Bactérias/metabolismo , Firmicutes/enzimologia , Firmicutes/metabolismo , Glicosídeo Hidrolases/metabolismo , Polissacarídeos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Firmicutes/química , Firmicutes/genética , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Concentração de Íons de Hidrogênio , Peso Molecular , Especificidade por Substrato
2.
Molecules ; 22(5)2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28445422

RESUMO

Qingwen Baidu Decoction (QBD) is an extraordinarily "cold" formula. It was traditionally used to cure epidemic hemorrhagic fever, intestinal typhoid fever, influenza, sepsis and so on. The purpose of this study was to discover relationships between the change of the constituents in different extracts of QBD and the pharmacological effect in a rat model of acute lung injury (ALI) induced by lipopolysaccharide (LPS). The study aimed to discover the changes in constituents of different QBD extracts and the pharmacological effects on acute lung injury (ALI) induced by LPS. The results demonstrated that high dose and middle dose of QBD had significantly potent anti-inflammatory effects and reduced pulmonary edema caused by ALI in rats (p < 0.05). To explore the underlying constituents of QBD, we assessed its influence of six different QBD extracts on ALI and analyzed the different constituents in the corresponding HPLC chromatograms by a Principal Component Analysis (PCA) method. The results showed that the pharmacological effect of QBD was related to the polarity of its extracts, and the medium polarity extracts E2 and E5 in particular displayed much better protective effects against ALI than other groups. Moreover, HPLC-DAD-ESI-MSn and PCA analysis showed that verbascoside and angoroside C played a key role in reducing pulmonary edema. In addition, the current study revealed that ethyl gallate, pentagalloylglucose, galloyl paeoniflorin, mudanpioside C and harpagoside can treat ALI mainly by reducing the total cells and infiltration of activated polymorphonuclear leukocytes (PMNs).


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Lesão Pulmonar Aguda/imunologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
3.
Acta Cardiol Sin ; 32(2): 194-204, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27122950

RESUMO

BACKGROUND: Impaired admission glucose (AG) is thought to significantly increase the risk of both early and late death with ST-segment elevation myocardial infarction (STEMI), especially for non-diabetic patients. However, several earlier studies contradict these relationships. Through our meta-analysis, we aimed to evaluate such a relation between impaired AG, the risk of death and STEMI. METHODS: We accessed PubMed, EMBASE, Web of Science, and the Cochrane Library and systematically searched their databases to identify all related prospective cohort studies. The relative risks (RRs) with their 95% confidence interval (CI) were pooled quantitatively. RESULTS: The pooled, unadjusted relative risks of early outcome events indicated that patients who had glucose concentrations ≥ the range of 6.1-11.1 mmol/L, had a 4.38-fold (95% CI, 3.23-5.94) higher early mortality. For late outcome events, the pooled unadjusted RR indicated patients who had glucose concentrations ≥ the range 7.8-11.1 mmol/L, and had a 2.69-fold (95% CI, 2.16-3.34) higher late mortality based on full participants, whereas patients had a 1.65-fold (95% CI, 1.33-2.04) higher late mortality based on based on in-hospital or 30-day survivors. CONCLUSIONS: In conclusion, the present meta-analysis demonstrated that impaired admission glucose may be an effective prognostic marker for significantly increased risk of early death. Regarding the long-term outcomes based on full population or early survival, high admission glucose also has a distinct but poorer prognostic impact on long-term mortality than early mortality. KEY WORDS: Admission glucose • Meta-analysis • Myocardial infarction • Non-diabetic.

4.
Neuroimage ; 59(4): 3173-7, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22108642

RESUMO

Studies of relapsing neuromyelitis optica (RNMO) using advanced MRI techniques are limited compared with those done on multiple sclerosis (MS). The present study used diffusion tensor imaging (DTI) to investigate whether occult brain damage exists in RNMO patients. DTI scans using a 3.0T MRI scanner were performed in 24 clinically confirmed RNMO patients whose conventional brain MRI results were normal, and also in 24 age- and sex-matched healthy control subjects. DTI data were processed to generate fractional anisotropy (FA) and mean diffusivity (MD) maps, and region of interest (ROI) analyses were performed to obtain these parameters in white matter (including medulla oblongata, cerebral peduncle, optic radiation, genu of corpus callosum, splenium of corpus callosum, and internal capsule) and gray matter (including thalamus and putamen). Regional measures from patients at stable and acute phases were compared with healthy controls. Both acute and stable NMO patients had a higher average FA in ROIs of the thalamus and putamen. Acute NMO patients had significantly higher average MDs than controls in the genu of corpus callosum and optic radiation, and significantly lower average MDs in the medulla oblongata. Stable NMO patients had increased MDs in the genu of corpus callosum and optic radiation, but lower MDs in the medulla oblongata, internal capsule and thalamus. The DTI findings confirm the presence of occult tissue damage in normal-appearance white and gray matter, especially deep gray matter, in RNMO patients. This study adds further to the evidence that DTI is suitable as a tool for characterizing subtle brain tissue damage.


Assuntos
Encefalopatias/diagnóstico , Encefalopatias/etiologia , Imagem de Tensor de Difusão/métodos , Neuromielite Óptica/complicações , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva , Adulto Jovem
5.
Huan Jing Ke Xue ; 41(11): 5037-5049, 2020 Nov 08.
Artigo em Zh | MEDLINE | ID: mdl-33124247

RESUMO

The aim of this study was to characterize the changes of the microbial community in WWTPs based on hybrid-MBBR process in the Yangtze River Delta in a low temperature season, and to obtain the regularity of the microbial distribution. High-throughput sequencing of Illumina miSeq was conducted to analyze the microbial community structure of activated sludge and suspended carrier biofilm in the aerobic area of five WWTPs. The results showed that the number of microbial species in the suspended carrier biofilm was lower than that of the activated sludge in the same plant, and the species distribution was more uneven. The addition of a suspended carrier can improve the microbial diversity of the system, while the influent and operation mode have a certain selectivity to the microbial community composition of the system. The bacteria with high relative abundance in each plant primarily included Nitrospira, Mycobacterium, Defluvicoccus, Hyphomacrobium, and Macrocharacters,etc. The addition of suspended carriers significantly enhanced the enrichment of Nitrospira. The amount of nitrifying bacteria in the suspended carrier accounted for 86.12%-95.36% of that of the whole system. A certain relative abundance of denitrifying bacteria was detected in the suspended carrier in the aerobic area of each plant. Combined with the results of the measurement of water quality along the process and the lab-scale experiment, it was confirmed that significant SND occurred on the suspended carrier biofilm in the aerobic area, which enhanced the TN removal of the system.


Assuntos
Reatores Biológicos , Nitrificação , Biofilmes , Desnitrificação , Nitrogênio/análise , Rios , Estações do Ano , Esgotos , Temperatura
6.
Nan Fang Yi Ke Da Xue Xue Bao ; 30(8): 1835-7, 2010 Aug.
Artigo em Zh | MEDLINE | ID: mdl-20813678

RESUMO

OBJECTIVE: To investigate the feasibility of repairing the wounds in the distal feet with dorsal metatarsal artery distal perforator pedicle link-pattern flaps. METHODS: Since January of 2004 to April of 2009, 30 patients with distal wounds in the feet underwent surgical wound repair using by dorsal metatarsal arteries distal perforator pedicle link-pattern flaps. Seventeen patients used the 1, 2 dorsal metatarsal artery distal perforator flaps, and 13 had the 3, 4 dorsal metatarsal artery distal perforator flaps, with the flaps measuring 4 cmx4 cm to 8 cmx7cm and the flap pedicle ranged 3-6 cm in length. The donor sites were repaired with skin grafting. RESULTS: Twenty-nine flaps survived completely and 1 flap showed partial necrosis in the distant part (2.0 cmx1.0 cm). Twenty-one patients were followed up for an average of 11 months, during which the color, texture, and contour of the flaps remained normal without ulcers in the donor sites or the flaps. CONCLUSION: The wounds in the distal feet can be repaired by dorsal metatarsal artery distal perforator pedicle link-pattern flaps, which is a simple, applicable and safe procedure.


Assuntos
Pé/cirurgia , Retalho Perfurante , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Adulto , Artérias/cirurgia , Feminino , Humanos , Masculino , Ossos do Metatarso/irrigação sanguínea , Pessoa de Meia-Idade , Retalho Perfurante/irrigação sanguínea , Transplante de Pele/métodos , Lesões dos Tecidos Moles/cirurgia , Adulto Jovem
7.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 26(4): 251-3, 2010 Jul.
Artigo em Zh | MEDLINE | ID: mdl-21046768

RESUMO

OBJECTIVE: To discuss the application of medial planta island flaps pedicled with anterior tibial artery perforator in front of inner malleolus for repairing small wounds around ankle. METHODS: From Jan. 2005 to Jun. 2009, 10 cases with small wounds around ankle were treated with medial planta island flaps pedicled with anterior tibial artery perforator. The flap size ranged from 7.5 cm x 2.8 cm to 13.0 cm x 5.0 cm. The wounds at the donor sites were covered with skin grafts. RESULTS: All the 10 flaps and skin grafts were survived with primary healing. The patients were followed up for 6-12 months with satisfactory cosmetic results. The 2-point discrimination was 4-6 mm when the proximal end of saphenous nerve was not injured, and it was 9-10 mm when the nerve was injured or cut off. The patients could walk with no occurrence of ulcer in flaps or donor site. CONCLUSIONS: The medial planta island flaps pedicled with anterior tibial artery perforator can effectively repair the small wounds around ankle with reliable blood supply.


Assuntos
Traumatismos do Tornozelo/cirurgia , Retalhos Cirúrgicos , Adulto , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Transplante de Pele , Retalhos Cirúrgicos/irrigação sanguínea , Artérias da Tíbia/cirurgia , Resultado do Tratamento , Adulto Jovem
8.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 25(6): 425-7, 2009 Nov.
Artigo em Zh | MEDLINE | ID: mdl-20209931

RESUMO

OBJECTIVE: To investigate the feasibility of fibular artery perforator link-pattern flaps at lateral and posterior part of legs. METHODS: From January 2007 to March 2009, 12 cases of with feet and ankle wounds were treat with fibular artery perforator link-pattern flaps at lateral and posterior part of legs. The flap size ranged from 10 cm x 10 cm to 25 cm x 13 cm. The wounds at the donor sites were closed with skin grafts. RESULTS: All the flaps survived completely. The patients were followed up for 1-12 months (median, 6 months). The color, texture and appearance of the flaps were good. CONCLUSION: The link-pattern flap has reliable blood supply and a large area for repairing defects. The sural nerve is reserved, resulting minimal morbidity to donor site.


Assuntos
Traumatismos do Tornozelo/cirurgia , Traumatismos do Pé/cirurgia , Transplante de Pele/métodos , Retalhos Cirúrgicos , Adolescente , Adulto , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Adulto Jovem
9.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 23(4): 293-4, 2007 Jul.
Artigo em Zh | MEDLINE | ID: mdl-17926848

RESUMO

OBJECTIVE: To report an anatomical basis for the posterior tibial artery intermuscular septum branches island flaps and its clinical value. METHODS: The origin,course, number, caliber and distribution of the posterior tibial artery intermuscular septum branches were studied in 10 adult cadavers(20 legs). 10 cases of homonymy and opposite side ankle and adjacent soft tissue defects with posterior tibial artery intermuscular septum branches island flaps, aged 20-50 years. Free skin transplantation on the donor sites. RESULTS: The posterior tibial artery gives off 2-7 intermuscular septum branches. Its external diameter was about 0.4-1.8 mm,and the length was about 0.3-4.5 cm. The area of flaps was 7 cm x 6 cm - 20 cm x 8 cm in the group. All the flaps were survived except 1 with partial necrosis in the distant part(3 cm x 1 cm) of the flap. 7 cases were followed up two months to three years. The color, texture and appearance of the flaps were good. CONCLUSIONS: The kind of flap has reliable blood supply, the scope of repairing was wide; avoidance of sacrificing the major artery; the flap was easy to be dissected. It was one of the ideal flaps to repair the ankle and adjacent soft tissue defects.


Assuntos
Retalhos Cirúrgicos , Artérias da Tíbia/anatomia & histologia , Artérias da Tíbia/transplante , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retalhos Cirúrgicos/irrigação sanguínea , Adulto Jovem
10.
Ai Zheng ; 26(8): 837-42, 2007 Aug.
Artigo em Zh | MEDLINE | ID: mdl-17697543

RESUMO

BACKGROUND & OBJECTIVE: Natural killer (NK) cells are the main effector of antibody-dependent cellular cytotoxicity (ADCC). The activation disorder of NK cells in cancer patients may affect the treatment effect of monoclonal antibody. Reversing the dysfunction of signal transduction of CD16zeta chain in NK cells and combining lymphokine-activated killer (LAK) cells with rituximab may give rise to synergistic effect. This study was to find out whether the activation disorder of NK cells exist in B-cell non-Hodgkin's lymphoma (B-NHL) patients, whether interleukin-2 (IL-2) can reverse the activation disorder in vitro, and whether the combination of rituximab and LAK cells can produce synergistic antitumor effect. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from 69 B-NHL patients and 30 healthy donors by density gradient centrifugation method, and cultured with IL-2 (1 000 U/ml) to prepare LAK cells. The positive rate and median fluorescence intensity (MFI) of CD16zeta chain in PBMCs and LAK cells were detected by flow cytometry (FCM). The expression of CD20 on Raji cells was also detected by FCM. The apoptosis of Raji cells after treatment of rituximab was detected by FCM with Annexin V/PI staining. The cytotoxicity was assessed by lactate dehydrogenase (LDH) release experiment. RESULTS: The positive rate and MFI value of CD16zeta chain on CD56+ cells were significantly lower in B-NHL group than in control group [(63.3+/-16.4)% vs. (97.8+/-3.1)%, P<0.001; 1.3+/-1.3 vs. 3.6+/-1.7, P<0.001]. There was no significant difference in the positive rate and MFI value of CD16zeta on LAK cells between the 2 groups [(99.3+/-4.1)% vs. (99.7+/-3.9)%, P=0.145; 29.2+/-12.5 vs. 31.4+/-13.8, P=0.44]. At the concentration of 40 mug/ml, rituximab completely combined CD20 antigens on cell membrane. The obvious enhancive effect of rituximab on cell apoptosis appeared at 24 h after treatment. The killing rate of Raji cells was significantly higher in rituximab combined LAK group than in LAK group (P<0.05). While the combination of LAK cells and Herceptin (40 mug/ml) didn't make a significant increase as compared with Herceptin alone (P>0.05). There was no significant difference in killing rate of Jurket cells between rituximab combined LAK group and LAK group (P>0.05). CONCLUSIONS: The down-regulation of CD16zeta chain expression widely exists in B-NHL patients, while high dose of IL-2 could enhance the expression of CD16zeta chain greatly in vitro. The combination of rituximab and LAK cells shows strong killing effect on Raji cells.


Assuntos
Anticorpos Monoclonais/farmacologia , Células Matadoras Ativadas por Linfocina/metabolismo , Células Matadoras Naturais/metabolismo , Linfoma de Células B , Receptores de IgG/metabolismo , Adulto , Idoso , Anticorpos Monoclonais Murinos , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Antígenos CD20/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Células Matadoras Ativadas por Linfocina/fisiologia , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Masculino , Pessoa de Meia-Idade , Rituximab , Adulto Jovem
11.
Zhonghua Shao Shang Za Zhi ; 21(3): 196-8, 2005 Jun.
Artigo em Zh | MEDLINE | ID: mdl-15996285

RESUMO

OBJECTIVE: To investigate the method of harvesting of superficial cervical artery island skin flap, and its clinical application in the repair of the maxillofacial and cervical scars. METHODS: The origin, course, branches and distribution of the superficial cervical artery were studied in 10 adult cadavers. The superficial cervical artery could be divided into three segments: i.e. the segment before entering the trapezius muscle, the segment in the trapezius muscle, and the segment emerging from the trapezius muscle. Fourteen patients with maxillofacial and cervical scar contracture were enrolled in the study. The postburn scars were removed, and the wounds were covered by superficial cervical artery island skin flaps. The survival of the flap after the operation and the recovery of the neck movements were observed. RESULTS: The length of superficial cervical artery before entering the trapezius muscle was 5.1 +/- 0.4 cm, while that inside the trapezius muscle was 2.1 +/- 0.5 cm, and that after emerging from the trapezius muscle was 4.7 +/- 0.7 cm, respectively. The internal perforating branch was located 7.3 +/- 0.6 cm beside the seventh cervical vertebrae, and 3.9 +/- 0.7 cm above the spine of scapula. The flap was from 16 cm x 7 cm to 35 cm x 12 cm in size. All the flaps survived, except one with partial necrosis in the distal part (3.0 cm x 1.5 cm) of the flap. Follow-up observation for 4 months to 3 years showed satisfactory results. CONCLUSION: Superficial cervical artery island skin flap is simple in the flap preparation, and there is no necessity to cut the pedicle, thus it is particularly suitable for the reconstruction of severe postburn maxillofacial and cervical contracture.


Assuntos
Cicatriz/cirurgia , Traumatismos Maxilofaciais/cirurgia , Lesões do Pescoço/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Transplante de Pele/métodos , Retalhos Cirúrgicos , Adolescente , Adulto , Artérias Carótidas/anatomia & histologia , Criança , Feminino , Seguimentos , Humanos , Masculino , Couro Cabeludo/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea
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