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1.
World J Gastrointest Endosc ; 15(9): 564-573, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37744321

RESUMO

BACKGROUND: We invented Endoscopic Ruler, a new endoscopic device to measure the size of varices in patients with cirrhosis and portal hypertension. AIM: To assess the feasibility and safety of Endoscopic Ruler, and evaluate the agreement on identifying large oesophageal varices (OV) between Endoscopic Ruler and the endoscopists, as well as the interobserver agreement on diagnosing large OV using Endoscopic Ruler. METHODS: We prospectively and consecutively enrolled patients with cirrhosis from 11 hospitals, all of whom got esophagogastroduodenoscopy (EGD) with Endoscopic Ruler. The primary study outcome was a successful measurement of the size of varices using Endoscopic Ruler. The secondary outcomes included adverse events, operation time, the agreement of identifying large OV between the objective measurement of Endoscopic Ruler and the empirical reading of endoscopists, together with the interobserver agreement on diagnosing large OV by Endoscopic Ruler. RESULTS: From November 2020 to April 2022, a total of 120 eligible patients with cirrhosis were recruited and all of them underwent EGD examinations with Endoscopic Ruler successfully without any adverse event. The median operation time of Endoscopic Ruler was 3.00 min [interquartile range (IQR): 3.00 min]. The kappa value between Endoscopic Ruler and the endoscopists while detecting large OV was 0.52, demonstrating a moderate agreement. The kappa value for diagnosing large OV using Endoscopic Ruler among the six independent observers was 0.77, demonstrating a substantial agreement. CONCLUSION: The data demonstrates that Endoscopic Ruler is feasible and safe for measuring the size of varices in patients with cirrhosis and portal hypertension. Endoscopic Ruler is potential to promote the clinical practice of the two-grade classification system of OV.

2.
Int J Biol Macromol ; 137: 1112-1120, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31271800

RESUMO

Six polysaccharides (SF-FB11, SF-HW21, SF-CA31, SF-HA41, SF-FF51, and SF-FR61) of similar molecular weights (MW) (30-50 kDa) were extracted from the fermentation liquor, mycelia, and basidiomata of Sparassis latifolia by different methods. Structural analyses of these purified polysaccharides indicated that they were all branched, with a degree of branching (DB) ranging from 0.2 to 0.4. The polysaccharides exhibited strong scavenging activities for 2,2­diphenyl­1­picrylhydrazyl and hydroxyl radicals. Their antioxidant activities were correlated to some extent with their composition but significantly with the DB. The polysaccharides with a low 1,3­d­glucose content and glucose: galactose ratio, or a low DB (0.2-0.3) had higher antioxidant activities. Additionally, the correlation between the extraction yield and antioxidant activities of the polysaccharides was assessed. The low-MW polysaccharides extracted by alkali treatments had both high yield and antioxidant activities. Additionally, both the yield and antioxidant activities were found to be influenced by the size, extraction method, and source (fermentation liquor, mycelia, or basidiomata) of the polysaccharides. These results indicate that polysaccharides isolated from S. latifolia have strong antioxidant activities closely associated with the polysaccharide structure and extraction method, thus providing a scientific basis for further use of these polysaccharides.


Assuntos
Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/isolamento & purificação , Polyporales/química , Compostos de Bifenilo/química , Radical Hidroxila/química , Peso Molecular , Micélio/química , Picratos/química
3.
Phlebology ; 34(1): 40-51, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29635965

RESUMO

OBJECTIVES: To report *The first two authors contributed equally to this work. our clinical experience on diagnostic criteria and endovascular management in patients with iliac venous compression syndrome. METHOD: Between July 2013 and May 2015, 85 consecutive patients with suspected iliac venous compression syndrome were evaluated by transfemoral venography and intravascular ultrasonography. Venographic evidence of iliac venous occlusion, stenosis, or pelvic collateral vessels, and the degree of stenosis as examined with intravascular ultrasonography were recorded. The endovascular procedure, complications, clinical outcome, and the Venous Clinical Severity Score were evaluated before and after the intervention. RESULTS: Of the 85 limbs, 66 cases of iliac venous compression syndrome were confirmed and 19 cases were excluded. In all of the 66 patients, we successfully performed endovascular intervention (22 balloon dilations, 44 balloon dilations + stenting). Two patients with stent implantation developed acute lower extremity deep vein thrombosis, resulted in successful lysis of the thrombus with catheter-directed thrombolysis. CONCLUSIONS: The presence of intraluminal spurs and pelvic collateral vessels represents not only pathological and anatomical changes by long-term mechanical compression, but also indicators of the severity of iliac venous compression syndrome. The degree of stenosis cannot accurately represent the severity and treatment of iliac venous compression syndrome, especially in the right iliac vein. Endovascular intervention is a safe and effective treatment that reduces lower extremity symptoms. Full and intentional dilation of the intraluminal spurs is an important technical aspect, which is often ignored.


Assuntos
Procedimentos Endovasculares , Veia Ilíaca , Síndrome de May-Thurner , Flebografia , Ultrassonografia de Intervenção , Adulto , Idoso , Feminino , Seguimentos , Humanos , Veia Ilíaca/diagnóstico por imagem , Veia Ilíaca/fisiopatologia , Veia Ilíaca/cirurgia , Masculino , Síndrome de May-Thurner/diagnóstico por imagem , Síndrome de May-Thurner/fisiopatologia , Síndrome de May-Thurner/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Bioresour Technol ; 201: 148-55, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26642220

RESUMO

A prominent delay with 12h was encountered in the phase shift from acidogenesis to solventogenesis in butanol production when the substrate-glucose was replaced by cassava flour. To solve this problem, different phase of pH regulation strategies were performed to shorten this delay time. With this effort, the phase shift occurred smoothly and the fermentation time was shortened. Under the optimal conditions, 16.24g/L butanol and 72h fermentation time were achieved, which were 25.3% higher and 14.3% shorter than those in the case of without pH regulation. Additionally, the effect of CaCO3 on "acid crash" and butanol production was also investigated. It was found that organic acids reassimilation would be of benefit to enhance butanol production. These results indicated that the simple but effective approach for acceleration of phase shift is a promising technique for shortening the fermentation time and improvement of butanol production.


Assuntos
1-Butanol/metabolismo , Clostridium acetobutylicum/metabolismo , Fermentação , Manihot , Biotecnologia , Clostridium acetobutylicum/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio
6.
Thromb Res ; 136(3): 642-51, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26251076

RESUMO

Deep venous thrombosis (DVT) is one of the most common peripheral vascular diseases. The roles of bone marrow-derived endothelial progenitor cells (EPCs) on the recanalization of venous thrombosis has been suggested recently, while the underlying mechanisms are not completely understood. Our objective was to investigate the functions of autophagy protein 5 (ATG5) in rat EPCs and its potential application in DVT. We have found that silencing of ATG5 or pharmacological suppression of ATG5 in rat EPCs reduces both the migration and psudotube formation under hypoxia in vitro. In line, overexpression of ATG5 significantly enhances the EPCs migration and psudotube formation capabilities. More importantly, injection of EPCs that stably express ATG5 increases EPC homing to the ischemic site and promotes thrombus recanalization in a rat DVT model in vivo. Mechanistically, we have shown that ATG5 overexpression enhances psudotube formation via the activation of AKT. These findings suggest that ATG5-AKT signaling plays an essential role in EPC migration and psudotube formation. Regulation of ATG5-AKT signaling may provide a potential novel therapy for DVT.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Proteína Oncogênica v-akt/metabolismo , Proteínas/metabolismo , Trombose Venosa/metabolismo , Trombose Venosa/terapia , Animais , Proteína 5 Relacionada à Autofagia , Movimento Celular , Células Cultivadas , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Masculino , Células-Tronco Mesenquimais/patologia , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento , Remodelação Vascular , Trombose Venosa/patologia
7.
Appl Biochem Biotechnol ; 175(2): 770-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25342268

RESUMO

Lycopene biosynthesis by Blakeslea trispora was greatly enhanced in a stirred-tank reactor when a nonsynchronous inoculation process, in which the (+) mating type was inoculated after the (-) mating type has been grown for a certain period of time, was applied. The lycopene concentration with nonsynchronous inoculation in a 24-h inoculation interval was 33 % higher than that with synchronous inoculation. The optimum inoculation ratio was 1:2 (+/-) at the 36 and 48 h inoculum age of mating types (+) and (-), respectively. Fermentation time for the individual strains and mated conditions showed that the (+) mating type grows faster than the (-) mating type. Morphological observation showed that the mycelium ratio of B. trispora (-) in mating culture with nonsynchronous inoculation was higher than that with synchronous inoculation. The results indicated that nonsynchronous inoculation process increased the dominance of B. trispora (-) in joint cultivation and hence stimulated lycopene biosynthesis.


Assuntos
Carotenoides/biossíntese , Mucorales/metabolismo , Micélio/metabolismo , Peptídeos/fisiologia , Biomassa , Reatores Biológicos , Fermentação , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Licopeno , Fator de Acasalamento , Fatores de Tempo
8.
Bioresour Technol ; 172: 276-282, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25270042

RESUMO

To obtain native strains resistant to butanol toxicity, a new isolating method and serial enrichment was used in this study. With this effort, mutant strain SE36 was obtained, which could withstand 35g/L (compared to 20g/L of the wild-type strain) butanol challenge. Based on 16s rDNA comparison, the mutant strain was identified as Clostridium acetobutylicum. Under the optimized condition, the phase shift was smoothly triggered and fermentation performances were consequently enhanced. The maximum total solvent and butanol concentration were 23.6% and 24.3%, respectively higher than that of the wild-type strain. Furthermore, the correlation between butanol produced and the butanol tolerance was investigated, suggesting that enhancing butanol tolerance could improve butanol production. These results indicate that the simple but effective isolation method and acclimatization process are a promising technique for isolation and improvement of butanol tolerance and production.


Assuntos
Acetona/metabolismo , Butanóis/metabolismo , Clostridium acetobutylicum/isolamento & purificação , Etanol/metabolismo , Manihot , Butanóis/toxicidade , Clostridium acetobutylicum/efeitos dos fármacos , Clostridium acetobutylicum/metabolismo , Compostos de Manganês , Sulfatos , Zea mays
9.
Appl Biochem Biotechnol ; 172(7): 3330-41, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24519630

RESUMO

The mutant strain designated as ART18, obtained from the wild-type strain Clostridium acetobutylicum PW12 treated by atmospheric and room temperature plasma, showed higher solvent tolerance and butanol production than that of the wild-type strain. The production of butanol was 11.3 ± 0.5 g/L, 31 % higher than that of the wild-type strain when it was used for acetone, butanol, and ethanol fermentation in P2 medium. Furthermore, the effects of cassava flour concentration, pH regulators, and vitamins on the ABE production were also investigated. The highest butanol production of 15.8 ± 0.8 g/L and butanol yield (0.31 g/g) were achieved after the above factors were optimized. When acetone, butanol, and ethanol fermentation by ART18 was carried out in a 15-L bioreactor, the butanol production, the productivity of butanol, and the total solvent were 16.3 ± 0.9, 0.19, and 0.28 g/L(/)h, respectively. These results indicate that ART18 is a promising industrial producer in ABE fermentation.


Assuntos
1-Butanol/metabolismo , Acetona/metabolismo , Clostridium acetobutylicum/genética , Clostridium acetobutylicum/metabolismo , Etanol/metabolismo , Manihot/metabolismo , Amido/metabolismo , Clostridium acetobutylicum/efeitos da radiação , Fermentação , Manihot/microbiologia , Mutagênese/efeitos da radiação , Mutação/efeitos da radiação , Ondas de Rádio
10.
Appl Biochem Biotechnol ; 171(7): 1692-700, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23996122

RESUMO

The zygomycete fungus Blakeslea trispora is usually used as a natural source of lycopene and ß-carotene. In this study, the B. trispora (-) strain, a major mating type for lycopene production, was treated with N(+) ion implantation and N-methyl-N'-nitro-N-nitrosoguanidine (NTG), and further isolated on the screening plates supplemented with lovastatin and crude extracts of trisporic acid (CTA). After several rounds of screening, four mutants with higher yield of lycopene and biomass were isolated. Among these mutants, I5 obtained with N(+) ion implantation showed a maximum lycopene yield (28.8 mg/g), which was 64 % higher than the parent strain (17.5 mg/g) in the production of lycopene. The results indicated that N(+) ion implantation is more suitable for B. trispora (-) than NTG treatment, and the addition of lovastatin promoted the generation of positive mutant and CTA amplified the color differences between colonies.


Assuntos
Carotenoides/biossíntese , Carotenoides/metabolismo , Mucorales/genética , Mucorales/metabolismo , Mutação , Ácidos Graxos Insaturados/farmacologia , Hidroximetilglutaril-CoA Redutases/genética , Lovastatina/farmacologia , Licopeno , Metilnitronitrosoguanidina/farmacologia , Mucorales/efeitos dos fármacos , Mucorales/crescimento & desenvolvimento , Mutação/efeitos dos fármacos , Nitrogênio/farmacologia , Fenótipo
11.
Bioresour Technol ; 137: 254-60, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23587827

RESUMO

In order to obtain mutant strains showing higher solvent tolerance and butanol production than those of wild-type strains, the butanol-producing strain Clostridium beijerinckii L175 was subjected to mutagenesis using a combined method of low-energy ion beam implantation and N-methyl-N-nitro-N-nitrosoguanidine induction. With this effort, mutant strain MUT3 was isolated. When it was used for butanol fermentation in P2 medium, the production of butanol was 15.8±0.7 g/L 46% higher than the wild-type strain. Furthermore, after optimization of butanol production from cane molasses with MUT3, the maximum butanol production of 14.9±0.5 g/L were obtained in crew-capped bottles. When ABE production by MUT3 was carried out in a bioreactor, the production of butanol and total solvent were 15.1±0.8 g/L and 22.1±0.9 g/L, respectively. The remarkable butanol production and solvent tolerance of MUT3 make it promising for butanol production from cane molasses.


Assuntos
Acetona/metabolismo , Butanóis/metabolismo , Clostridium beijerinckii/genética , Etanol/metabolismo , Melaço , Nitrosoguanidinas/metabolismo , Reatores Biológicos , Clostridium beijerinckii/metabolismo , Fermentação , Mutagênese
12.
Multidiscip Respir Med ; 8(1): 21, 2013 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-23506629

RESUMO

BACKGROUND: To investigate the utilization of PET-CT in target volume delineation for three-dimensional conformal radiotherapy in patients with non-small cell lung cancer (NSCLC) and atelectasis. METHODS: Thirty NSCLC patients who underwent radical radiotherapy from August 2010 to March 2012 were included in this study. All patients were pathologically confirmed to have atelectasis by imaging examination. PET-CT scanning was performed in these patients. According to the PET-CT scan results, the gross tumor volume (GTV) and organs at risk (OARs, including the lungs, heart, esophagus and spinal cord) were delineated separately both on CT and PET-CT images. The clinical target volume (CTV) was defined as the GTV plus a margin of 6-8 mm, and the planning target volume (PTV) as the GTV plus a margin of 10-15mm. An experienced physician was responsible for designing treatment plans PlanCT and PlanPET-CT on CT image sets. 95% of the PTV was encompassed by the 90% isodose curve, and the two treatment plans kept the same beam direction, beam number, gantry angle, and position of the multi-leaf collimator as much as possible. The GTV was compared using a target delineation system, and doses distributions to OARs were compared on the basis of dose-volume histogram (DVH) parameters. RESULTS: The GTVCT and GTVPET-CT had varying degrees of change in all 30 patients, and the changes in the GTVCT and GTVPET-CT exceeded 25% in 12 (40%) patients. The GTVPET-CT decreased in varying degrees compared to the GTVCT in 22 patients. Their median GTVPET-CT and median GTVPET-CT were 111.4 cm3 (range, 37.8 cm3-188.7 cm3) and 155.1 cm3 (range, 76.2 cm3-301.0 cm3), respectively, and the former was 43.7 cm3 (28.2%) less than the latter. The GTVPET-CT increased in varying degrees compared to the GTVCT in 8 patients. Their median GTVPET-CT and median GTVPET-CT were 144.7 cm3 (range, 125.4 cm3-178.7 cm3) and 125.8 cm3 (range, 105.6 cm3-153.5 cm3), respectively, and the former was 18.9 cm3 (15.0%) greater than the latter. Compared to PlanCT parameters, PlanPET-CT parameters showed varying degrees of changes. The changes in lung V20, V30, esophageal V50 and V55 were statistically significant (Ps< 0.05 for all), while the differences in mean lung dose, lung V5, V10, V15, heart V30, mean esophageal dose, esophagus Dmax, and spinal cord Dmax were not significant (Ps> 0.05 for all). CONCLUSIONS: PET-CT allows a better distinction between the collapsed lung tissue and tumor tissue, improving the accuracy of radiotherapy target delineation, and reducing radiation damage to the surrounding OARs in NSCLC patients with atelectasis.

13.
Bioresour Technol ; 130: 638-43, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23334021

RESUMO

To improve butanol tolerance and production in Clostridium acetobutylicum, a novel approach was developed in this study, which was called artificial simulation of bio-evolution (ASBE) based on the evolutionary dynamics and natural selection. Through repetitive evolutionary domestications, a butanol-tolerant strain C. acetobutylicum T64 was obtained, which could withstand 4% (v/v) (compared to 2% of the wild-type) butanol and was accompanied by the increase of butanol production from 12.2g/L to 15.3g/L using corn meal as substrate. Fermentation was also carried out to investigate the relationship between butanol tolerance and ABE production, suggesting that enhancing butanol tolerance could increase butanol production but unlikely improve total ABE production. These results also indicated that the ASBE would be an available and feasible method used in biotechnology for enhancement of butanol tolerance and production.


Assuntos
Evolução Biológica , Butanóis/toxicidade , Clostridium acetobutylicum/efeitos dos fármacos , Clostridium acetobutylicum/genética , Seleção Genética , Biocombustíveis , Proliferação de Células , Clostridium acetobutylicum/citologia , Cinética
14.
J Microbiol ; 50(6): 1024-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23274990

RESUMO

As a promising alternative biofuel, biobutanol can be produced through acetone/butanol/ethanol (ABE) fermentation. Currently, ABE fermentation is still a small-scale industry due to its low production and high input cost. Moreover, butanol toxicity to the Clostridium fermentation host limits the accumulation of butanol in the fermentation broth. The wild-type Clostridium acetobutylicum D64 can only produce about 13 g butanol/L and tolerates less than 2% (v/v) butanol. To improve the tolerance of C. acetobutylicum D64 for enhancing the production of butanol, nitrogen ion beam implantation was employed and finally five mutants with enhanced butanol tolerance were obtained. Among these, the most butanol tolerant mutant C. acetobutylicum NT642 can tolerate above 3% (v/v) butanol while the wide-type strain can only withstand 2% (v/v). In batch fermentation, the production of butanol and ABE yield of C. acetobutylicum NT642 was 15.4 g/L and 22.3 g/L, respectively, which were both higher than those of its parental strain and the other mutants using corn or cassava as substrate. Enhancing butanol tolerance is a great precondition for obtaining a hyper-yield producer. Nitrogen ion beam implantation could be a promising biotechnology to improve butanol tolerance and production of the host strain C. acetobutylicum.


Assuntos
Butanóis/metabolismo , Clostridium acetobutylicum/genética , Clostridium acetobutylicum/metabolismo , Mutação , Nitrogênio/metabolismo , Biocombustíveis , Clostridium acetobutylicum/crescimento & desenvolvimento , Fermentação
15.
Appl Microbiol Biotechnol ; 93(1): 367-79, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21739265

RESUMO

A significant problem in scale-down cultures, rarely studied for metabolic characterization and curdlan-producing Agrobacterium sp. ATCC 31749, is the presence of dissolved oxygen (DO) gradients combined with pH control. Constant DO, between 5% and 75%, was maintained during batch fermentations by manipulating the agitation with PID system. Fermentation, metabolic and kinetic characterization studies were conducted in a scale-down system. The curdlan yield, intracellular nucleotide levels and glucose conversion efficiency into curdlan were significantly affected by DO concentrations. The optimum DO concentrations for curdlan production were 45-60%. The average curdlan yield, curdlan productivity and glucose conversion efficiency into curdlan were enhanced by 80%, 66% and 32%, respectively, compared to that at 15% DO. No apparent difference in the gel strength of the resulting curdlan was detected. The comparison of curdlan biosynthesis and cellular nucleotide levels showed that curdlan production had positive relationship with intracellular levels of UTP, ADP, AMP, NAD(+), NADH and UDP-glucose. The curdlan productivity under 45% DO and 60% DO was different during 20-50 h. However, after 60 h curdlan productivity of both conditions was similar. On that basis, a simple and reproducible two-stage DO control process for curdlan production was developed. Curdlan production yield reached 42.8 g/l, an increase of 30% compared to that of the single agitation speed control process.


Assuntos
Agrobacterium/metabolismo , Fermentação , Oxigênio/metabolismo , beta-Glucanas/metabolismo , Agrobacterium/crescimento & desenvolvimento , Meios de Cultura/química , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Nucleotídeos/metabolismo , Fatores de Tempo
16.
Appl Microbiol Biotechnol ; 91(1): 163-75, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21472535

RESUMO

Expression at the mRNA level of ten selected genes in Agrobacterium sp. ATCC 31749 under various dissolved oxygen (DO) levels during curdlan fermentation related to electron transfer chain (ETC), tricarboxylic acid (TCA) cycle, peptidoglycan/lipopolysaccharide biosynthesis, and uridine diphosphate (UDP)-glucose biosynthesis were determined by qRT-PCR. Experiments were performed at DO levels of 30%, 50%, and 75%, as well as under low-oxygen conditions. The effect of high cell density on transcriptional response of the above genes under low oxygen was also studied. Besides cytochrome d (cyd A), the transcription levels of all the other genes were increased at higher DO and reached maximum at 50% DO. Under 75% DO, the transcriptional levels of all the genes were repressed. In addition, transcription levels of icd, sdh, cyo A, and fix N genes did not exhibit significant fluctuation with high cell density culture under low oxygen. These results suggested a mechanism for DO regulation of curdlan synthesis through regulation of transcriptional levels of ETCs, TCA, and UDP-glucose synthesis genes during curdlan fermentation. To our knowledge, this is the first report that DO concentration apparently regulates curdlan biosynthesis in Agrobacterium sp. ATCC 31749 providing essential lead for the optimization of the fermentation at the industrial scale.


Assuntos
Oxigênio/metabolismo , Rhizobium/genética , Rhizobium/metabolismo , Transcrição Gênica , beta-Glucanas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Dados de Sequência Molecular
17.
Chin Med J (Engl) ; 123(4): 471-7, 2010 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-20193489

RESUMO

BACKGROUND: The organization and recanalization of thrombi is a dynamic and complex process. The aim of this research was to study the cotherapeutic effect of stem cell transplantation and gene transfection on chronic venous thrombosis. METHODS: We constructed a recombinant adenoviral vector carrying the vascular endothelial growth factor 165 (VEGF165) gene by using the pAdEasy system, which was subsequently identified and amplified. Simultaneously, endothelial progenitor cells (EPCs) were isolated from rat bone marrow using Ficoll, cultured in EBM-2MV medium, and identified. Then, the cells were transfected with the recombinant Ad-VEGF165. The EPCs were labeled with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine (Dil) before transplantation. A rat model of chronic vein thrombosis was developed by partial ligation of the inferior vena cava. The rats were randomly divided into 4 groups (n = 25, each): A, Ad-VEGF165/EPC-transplantation group received 1 ml (10(6)) of Ad-VEGF165/EPCs; B, EPC-transplantation group received 1 ml (10(6)) of EPCs; C, Ad/EPC-transplantation group received 1 ml (10(6)) of Ad/EPCs; D, control group received 1 ml of the transplantation medium. The thrombi and adjacent caval walls were harvested 28 days after transplantation; real-time quantitative polymerase chain reaction was used to detect the expression level of vascular endothelial growth factor (VEGF) mRNA; and western blotting was used to measure changes in VEGF protein expression. Hematoxylin-eosin staining and immunohistochemical staining were performed to detect recanalization. Neovascularization was detected by immunohistochemical staining using the antibody for von Willebrand factor (vWF), which is a component of endothelial cells. The capillary density was quantitatively determined by counting the capillaries under a high-power microscope. RESULTS: The Ad-VEGF165 was constructed, and bone-marrow-derived EPCs were cultivated and successfully identified. We determined the optimum transfection ratio that promoted the growth of EPCs. After transfection, the EPCs secreted the VEGF protein. After transplantation, the in vivo survival of EPCs and their differentiation into endothelial cells were determined by detecting the fluorescence associated with the Dil stain. VEGF mRNA was expressed in groups A, B, C and D after transplantation, and the VEGF mRNA level in group A was significantly higher than those in groups B, C and D (P < 0.05); the VEGF mRNA levels in groups B and C were significantly higher than those in group D (P < 0.05), and there was no statistical significance between the VEGF mRNA levels in groups B and C. The recanalization capillary density in group A was significantly higher than those in groups B, C (P < 0.05) and D (P < 0.01); the recanalization capillary densities in groups B and C were significantly higher than that in group D (P < 0.05). Moreover, there was no statistical significant difference between the values for groups B and C. CONCLUSIONS: The EPCs were successfully transfected by Ad-VEGF165. A suitable transfection ratio can improve the efficiency of EPCs and the possibility of promotion of angiogenesis after transplantation. Transfected EPCs caused accelerated organization and recanalization of vein thrombi.


Assuntos
Células Endoteliais/citologia , Células-Tronco/citologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Trombose Venosa/terapia , Animais , Proliferação de Células , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Masculino , Ratos , Ratos Wistar , Transplante de Células-Tronco , Células-Tronco/fisiologia , Fator A de Crescimento do Endotélio Vascular/genética
18.
J Cell Biochem ; 96(4): 741-50, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16088917

RESUMO

Human NUDC (hNUDC) was initially characterized as a nuclear migration protein based on the similarity of its C-terminus to that of fungal NUDC from Aspergillus nidulans. However, hNUDC is a 331 amino acid protein whereas fungal NUDC is 198 amino acids in length. The extra N-terminal portion of hNUDC has no known function or homology to other proteins. In this study, we report the binding of hNUDC to the extracellular domain of the thrombopoietin receptor (Mpl) as detected by the yeast two-hybrid system, GST pull-down, and co-immunoprecipitation. Our deletion analysis demonstrated that amino acids between positions 100 and 238 as the critical domain mediating the hNUDC and Mpl interactions as detected by the two-hybrid system and GST pull-down assay. Immunofluorescence staining of human megakaryocyte cells indicated that hNUDC and Mpl colocalized at all stages of megakaryocyte development. Substantial colocalization of hNUDC with microtubules was also detected around nuclei and elongated microtubular structures, especially in proplatelet extensions.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Citocinas/metabolismo , Western Blotting , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Células Cultivadas , Humanos , Imunoprecipitação , Megacariócitos/citologia , Megacariócitos/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/genética , Ligação Proteica , Estrutura Terciária de Proteína , Transporte Proteico , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Receptores de Citocinas/química , Receptores de Citocinas/genética , Receptores de Trombopoetina , Proteínas Recombinantes de Fusão , Deleção de Sequência , Tubulina (Proteína)/metabolismo , Técnicas do Sistema de Duplo-Híbrido
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