RESUMEN
(S)-2-chlorophenylglycine methyl ester ((S)-1) is a key chiral building block of clopidogrel, which is a widely administered antiaggregatory and antithrombotic drug. Herein, Protease 6SD was covalently immobilized on multi-walled carbon nanotubes (MWCNT), and the as-prepared immobilizate P-6SD@NH2-MWCNT was applied in the enantioselective resolution of (R,S)-1 to yield (S)-1. In order to overcome the poor solubility of (R,S)-1 in aqueous solution, a novel triphasic reaction system constituting P-6SD@NH2-MWCNT, aqueous phase and methyl tert-butyl ether (MTBE) as the organic phase was constructed, which simultaneously improved the substrate solubility and the immobilizate recyclability. Under the optimized reaction conditions, P-6SD@NH2-MWCNT catalyzed 10â¯mM (R,S)-1 for 2â¯h, yielding optically pure (S)-1 (>99.0 % ees) with 70.74 % conversion of the (R,S)-1. Moreover, P-6SD@NH2-MWCNT can be reused for 15 batches, displaying an exquisite recycling performance. It is for the first time that enantiomerically pure (S)-1 was successfully synthesized by protease-catalyzed one-step resolution.
Asunto(s)
Ésteres , Nanotubos de Carbono , Catálisis , Enzimas Inmovilizadas , Péptido HidrolasasRESUMEN
t-Butyl 6-cyano-(3R,5R)-dihydroxyhexanoate ((3R,5R)-2) is an important building-block of atorvastatin. In our previous work, a variant KlAKR-Y295W-W296â¯L (designated as M1) of Kluyveromyces lactis aldo-keto reductase (wild type (WT) KlAKR, M0) was developed, which possessed strict diastereoselectivity but moderate activity towards t-butyl 6-cyano-(5R)-hydroxy-3-oxohexanoate ((5R)-1). To further improve its catalytic performance, semi-rational engineering of M1 was performed in present work, and the "best" varaint KlAKR-Y295W-W296L-I125V-S30P-Q212R-I63W (M8) was developed. M8's KmB towards (5R)-1 was 2.02â¯mM, and the catalytic efficiency (kcat/KmB) value was 36.31 s-1â¯mM-1, which was 1.9-fold higher than that of the parent M1. Compared with M1, the half-life t1/2, TS5050 and TP5050 of M8 were improved. Under the optimized conditions, (5R)-1 at load of up to 80â¯g L-1 was completely reduced in 1.5â¯h by M8 along with Exiguobacterium sibiricum glucose dehydrogenase (EsGDH) for cofactor regeneration, producing (3R,5R)-2 in dep > 99.5% and space-time yields (STY) of 660.0â¯g L-1d-1.
Asunto(s)
Aldo-Ceto Reductasas/genética , Proteínas Bacterianas/genética , Caproatos/metabolismo , Kluyveromyces/enzimología , Ingeniería de Proteínas , Aldo-Ceto Reductasas/metabolismo , Proteínas Bacterianas/metabolismo , Catálisis , Glucosa 1-Deshidrogenasa/metabolismo , Concentración de Iones de Hidrógeno , CinéticaRESUMEN
OBJECTIVE: To investigate the expression of axis inhibition protein (AXIN) and metastasis-associated in colon cancer-1 (MACC1) in gastric carcinoma and their relationship to the clinicopathologic characteristics. METHODS: Expressions of AXIN and MACC1 proteins were examined by immunohistochemistry containing 100 specimens of gastric tissues (gastric carcinoma group) and 60 specimens of normal gastric mucosa tissues (control group,the nearby tissues of the excised specimen of gastric cancer patients,from the tumor of the gastric cancer >5.0 cm,and confirm that there were no cancer cells). RESULTS: The positive rates of AXIN and MACC1 proteins in gastric carcinoma and the control tissues were 37.0% vs. 83.3% and 58.0% vs. 6.7%,respectively. The difference were significant between the two groups (both P<0.05). The expressions of AXIN and MACC1 proteins were significantly related with grades of tumor,depth of invasion,lymph node metastasis,and Duke stages ( P<0.05). Spearman analysis showed that there was a negative relationship between the AXIN expression and MACC1 expression (r=-0.355, P<0.05). Kaplan-Meier survival analysis and log-rank single factor analysis showed that AXIN and MACC1 protein expressions were related to the 5-year survival rate of patients (both P<0.05). Cox regression analysis showed that the positive expression of AXIN and the negative expression MACC1 protein,and Duke stages (â ¢-â £) were the independent prognostic factors of gastric carcinoma. CONCLUSION: The expressions of AXIN and MACC1 proteins are related to the prognosis of gastric carcinoma patients,and are involved in the invasion and metastasis of gastric carcinoma.
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Proteína Axina/metabolismo , Neoplasias Gástricas/metabolismo , Factores de Transcripción/metabolismo , Biomarcadores de Tumor/metabolismo , Estudios de Casos y Controles , Humanos , Inmunohistoquímica , Estadificación de Neoplasias , Pronóstico , TransactivadoresRESUMEN
AIM: To evaluate the hemostatic effect of topical hemocoagulase spray in digestive endoscopy. METHODS: Eighty-nine patients who developed oozing bleeding during endoscopic treatment from September 2014 to October 2014 at Center for Digestive Endoscopy, Tianjin Medical University General Hospital were randomly divided into either a study group (n = 39) or a control group (n = 50). The study group was given topical hemocoagulase spray intraoperatively, while the control group was given traditional 8% norepinephrine spray. Hemostatic efficacy was compared between the two groups. Bleeding site, wound cleanliness and perforation were recorded, and the rates of perforation and late bleeding were compared. RESULTS: Successful hemostasis was achieved in 39 (100%) patients of the study group and in 47 (94.0%) patients of the control group, and there was no significant difference in the rate of successful hemostasis between the two groups. Compared with the control group, after topical hemocoagulase spray in the study group, the surgical field was clearer, the bleeding site was more easily identified, and the wound was cleaner. There was no significant difference in the rate of perforation between the study and control groups (16.7% vs 35.0%, P = 0.477), but the rates of late bleeding (0% vs 15.8%, P = 0.048) and overall complications (P = 0.032) were significantly lower in the study group. CONCLUSION: Topical hemocoagulase spray has a definite hemostatic effect for oozing bleeding in digestive endoscopy, and this method is convenient, safe, and reliable. It is expected to become a new method for endoscopic hemostasis.
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Batroxobina/uso terapéutico , Resección Endoscópica de la Mucosa/métodos , Hemostasis Endoscópica/métodos , Hemostáticos/uso terapéutico , Administración Tópica , Endoscopía del Sistema Digestivo/métodos , Femenino , Humanos , Perforación Intestinal/epidemiología , Masculino , Persona de Mediana Edad , Norepinefrina/uso terapéutico , Complicaciones Posoperatorias/epidemiología , Hemorragia Posoperatoria/epidemiología , Resultado del Tratamiento , Vasoconstrictores/uso terapéuticoRESUMEN
Muscovy duck parvovirus (MDPV) infection is widespread in many Muscovy-duck-farming countries, leading to a huge economic loss. By means of overlapping peptides expressed in Escherichia coli in combination with Western blot, antigenic domains on the non-structural protein (NSP) of MDPV were identified for the first time. On the Western blot, the fragments NS(481-510), NS (501-530), NS (521-550), NS (541-570), NS (561-590), NS (581-610) and NS (601-627) were positive (the numbers in parentheses indicate the location of amino acids), and other fragments were negative. These seven fragments were also reactive in an indirect enzyme-linked immunosorbent assay (i-ELISA). We therefore conclude that a linear antigenic domain of the NSP is located at its C-terminal end (amino acid residues 481-627). These results may facilitate future investigations into the function of NSP of MDPV and the development of immunoassays for the diagnosis of MDPV infection.
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Infecciones por Parvoviridae/veterinaria , Parvovirus/inmunología , Enfermedades de las Aves de Corral/virología , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/inmunología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Anticuerpos Antivirales/inmunología , Patos , Mapeo Epitopo , Datos de Secuencia Molecular , Infecciones por Parvoviridae/inmunología , Infecciones por Parvoviridae/virología , Parvovirus/química , Parvovirus/genética , Parvovirus/aislamiento & purificación , Enfermedades de las Aves de Corral/inmunología , Alineación de Secuencia , Proteínas no Estructurales Virales/genéticaRESUMEN
OBJECTIVE: To investigate the correlations among OCT4, Notch1 and DLL4 and their association with the clinicopathological features of patients with epithelial ovarian cancer (EOC). METHODS: A total of 207 specimens of EOC and 65 specimens of benign ovarian epithelial tumor tissues were examined for expressions of OCT4, Notch1 and DLL4 proteins using immunohistochemistry. RESULTS: The positivity rates of OCT4, Notch1 and DLL4 in EOC tissues were 60.0%, 61.8% and 60.9%, respectively, significantly higher than the rates in benign epithelial tumor tissues (9.2%, 6.2%, and 0, respectively; P<0.05). The expressions of OCT4, Notch1 and DLL4 in EOC were significantly correlated with tumor differentiation, FIGO stage, and lymph node metastasis (P<0.05). DLL4 was positively correlated with OCT4 and Notch1 expressions (r=0.758 and 0.704, respectively, P<0.001), and the latter two were also positively correlated (r=0.645, P<0.001). Overexpressions of OCT4, Notch1 and DLL4 were associated with a poor prognosis, and the survival rate was significantly lower in patients positive for OCT4, Notch1, and DLL4 than in the negative patients (P<0.05). FIGO stage and expressions of OCT4 and DLL4 were independent prognostic factors of EOC (P<0.05). CONCLUSION: The expressions of OCT4, Notch1 and DLL4 are correlated with the differentiation, lymph node metastasis, clinical stage and prognosis of EOC. Combined detection of the 3 proteins has an important value in predicting the progression and prognosis of EOC.
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Péptidos y Proteínas de Señalización Intercelular/metabolismo , Neoplasias Glandulares y Epiteliales/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Neoplasias Ováricas/metabolismo , Receptor Notch1/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Proteínas de Unión al Calcio , Carcinoma Epitelial de Ovario , Progresión de la Enfermedad , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/patología , Pronóstico , Tasa de SupervivenciaRESUMEN
BACKGROUND: Gastric cancer is the second leading cause of cancer-related death in Asia, and the majority type is gastric adenocarcinoma (GAC). Most GAC patients die of recurrence and metastasis. Cancer stem cells (CSCs) have been thought to be responsible for the initiation, development, metastasis, and ultimately recurrence of cancer. In this study, we aimed to investigate expression and clinical significance of CSCs markers, CD133 and Lgr5, and vasculogenic mimicry (VM) in primary GAC. MATERIALS AND METHODS: Specimens from 261 Chinese patients with follow-up were analyzed for CD133, Lgr5 protein expression and VM by immunohistochemical and histochemical staining. The Pearson Chi's square test was used to assess the associations among the positive staining of these markers and clinicopathological characteristics. Postoperative overall survival time was were studied by univariate and multivariate analyses. RESULTS: In GAC tissues, positive rates of 49.0%, 38.7%, and 26.8% were obtained for CD133, Lgr5, and VM, respectively. The mean score of microvessel density (MVD) was 21.7±11.1 in GAC tissues. There was a significantly difference between the positive and negative groups. There was a positive relationship between the VM, the expression of CD133 and Lgr5, and the score of MVD and the grades of tumor, lymph node metastasis, TNM stages (all p<0.05). The overall mean survival time of the patients with CD133, Lgr5, VM, and MVD (≥22) positive expression was lower than that of patients with negative expression. The score of MVD, positive expression of CD133 and VM were independent prognostic factors of GAC (p<0.05). CONCLUSIONS: VM, and expression of CD133, Lgr5, and the score of MVD are related to grades of tumor, lymph node metastasis, TNM stages, and overall mean survival time. It is suggested that CSCs and VM could play an important role in the evolution of GAC.
Asunto(s)
Adenocarcinoma/química , Adenocarcinoma/secundario , Biomarcadores de Tumor/análisis , Células Madre Neoplásicas/química , Neovascularización Patológica/metabolismo , Neoplasias Gástricas/química , Neoplasias Gástricas/patología , Antígeno AC133 , Adenocarcinoma/irrigación sanguínea , Antígenos CD/análisis , Cadherinas/análisis , Femenino , Glicoproteínas/análisis , Humanos , Inmunohistoquímica , Metástasis Linfática , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Invasividad Neoplásica , Estadificación de Neoplasias , Péptidos/análisis , Receptores Acoplados a Proteínas G/análisis , Estómago/química , Neoplasias Gástricas/irrigación sanguínea , Tasa de SupervivenciaRESUMEN
OBJECTIVE: To seek good markers to predict invasion and metastasis of gastric adenocarcinoma (GAC). METHODS: Expression of Kangai 1 (KAI1), CD34, and D2-40 were examined by immunohistochemistry containing 145 specimens of GAC and 50 specimens of normal gastric tissue. Microvessel density (MVD) and lymph vessel density (LVD) were determined by the mean number of small CD34-positive or D2-40-positive vessels counted. And the relationship of KAI1, MVD and LVD, as well as the role of them on invasion, metastasis and prognosis in GAC were analyzed. RESULTS: The positive rate of KAI1, the median scores of MVD and LVD in normal gastric tissue and GAC tissue were 92.0%, (9.2 +/- 7.8)/LP, (7.5 +/- 7.6)/LP and 37.2%, (21.6 +/- 9. 1)/ LP, (22.6 +/- 12.7)/LP, respectively. And there was a significant different between the two groups (P < 0.05). The expression of KAI1, the scores of MVD and LVD were significantly related with pathologic-tumor-node metastasis (pTNM) stages, depth of invation and lymph node metastasis (all P < 0.05). There was a significant relationship between the expression of KAI1 and the scores of MVD or LVD. The survival rate of the KAI1-positive or KAI1-negative group was significantly different (P < 0.01); the survival rates were significantly lower in MVD > or = 22's group than that in MVD < 22's group, so was the same relationship between the LVD > or = 23's group and the LVD < 23's group (both P < 0.01). Cox regression analysis: pTNM stage, expression of KAI1, and the scores of MVD were independent factors of postoperative survival time in GAC (P < 0.05). CONCLUSION: The combined detection of KAI1, CD34, and D2-40 has an important role in predicting the progression and prognosis of GAC.