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1.
Zhonghua Yi Shi Za Zhi ; 53(4): 240-244, 2023 Jul 28.
Artículo en Chino | MEDLINE | ID: mdl-37727003

RESUMEN

Yang ke xuan cui («¼) is a surgical work compiled by Chen Wenzhi () of the Ming Dynasty. There are few of research on the completion and author of the book. Based on the evidences in the local chronicles, the prefaces and postscripts of the book, it has been verified that the book was originally completed no later than 1591, and Chen Wenzhi passed away no later than 1623. After investigating the 6 editions collected by 8 institutions, a collection of 11 books in total, by comparing the characteristics and circulation relationship of each edition, two systems of circulation were sorted out: block-printed edition of Xu Xi () and review edition of Xu Dachun ().


Asunto(s)
Libros , Cirugía General , Libros/historia , Historia del Siglo XVII , Historia del Siglo XVI
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(11): 1144-1149, 2021 Nov 09.
Artículo en Chino | MEDLINE | ID: mdl-34763413

RESUMEN

Both pathological injuries and clinical iatrogenic operations can lead to dentin demineralization, forming demineralized dentin matrix (DDM). Dentin demineralization activates endogenous matrix metalloproteinase (MMP) and cysteine cathepsin (CC), and the mechanical properties of DDM decrease, so DDM is prone to lose its structural integrity under the action of enzymatic degradation and mechanical destruction, which in turn results in the reduction of clinical functional value of DDM in dentin-resin bonding restoration. The administrations of dentin collagen cross-linking reagents and MMP/CC inhibitors are effective strategies to protect DDM structural integrity and achieve its clinical functional value. A variety of chemically synthesized reagents and plant-derived extracts are capable of significantly improving the mechanical properties of DDM and enhancing its enzymatic tolerance. However, the cytotoxicity caused by chemically synthesized reagents and the tooth staining aroused by plant extracts have considerably affected their clinical applicability. Protecting dentin collagen while exerting antibacterial properties is a new direction for future DDM protective agent research. Accordingly, from the perspectives of cross-linking reagents, enzyme inhibitors and compounds which possess the dual proper ties, this review discusses the latest research progress in DDM protection, and looks into its application prospects in dentin-resin bonding, in an attempt to provide reference for the clinical promotion of DDM protection strategy.


Asunto(s)
Colágeno , Dentina , Metaloproteinasas de la Matriz
5.
Zhonghua Er Ke Za Zhi ; 54(12): 917-922, 2016 Dec 02.
Artículo en Chino | MEDLINE | ID: mdl-27938592

RESUMEN

Objective: To analyze the clinical characteristics and prognosis of rare soft tissue sarcomas. Method: Clinical data of 51 patients with rare soft tissue sarcomas including fibrosarcoma, synovial sarcoma, extrarenal rhabdoid tumor, alveolar soft part sarcoma, desmoplastic small round cell tumor and undifferentiated sarcoma in children and adolescents, diagnosed at Shanghai Children's Medical Center from June 1998 to December 2013, were retrospectively analyzed. All types were treated with the same strategy and chemotherapy regimens. Their clinical features, treatment and prognosis were discussed. Result: Seventeen patients with fibrosarcoma, 10 with synovial sarcoma, 9 with extrarenal rhabdoid tumor, 6 with alveolar soft part sarcoma, 3 with desmoplastic small round cell tumor and 6 with undifferentiated sarcoma were included. The mean age at initial diagnosis was 5 years(range from 1 month to 13.5 years). The most common primary site of tumors was limbs, followed by the thoracic and abdominal cavity, accounting for 41% and 24% respectively. Twelve cases presented distant tissue or organ involvement in which bone metastases occupied the first place. Seven cases(accounting for 14%)were at stage Ⅰ, 13 cases were at stage Ⅱ(accounting for 25%), 19 cases were at stage Ⅲ(accounting for 37%) and 12 cases were at stage Ⅳ(accounting for 24%). The median follow-up period was 36 months(range from 1 month to 123 months). Forty-four patients achieved complete remission and 3 patients achieved partial remission after initial treatment, the overall response rate was 92%. Subsequent follow-up showed 29 patients remained relapse-free while 13 patients had relapsed disease. Overall survival and event-free survival at 2 years were 88% and 57%.Postoperative surgical staging was the main prognostic factors. Patients with stage Ⅲ+ Ⅳ had poorer results than those with Ⅰ+ Ⅱ (χ2=4.909, P=0.027). Conclusion: These 6 types of soft tissue sarcomas are rare in children and adolescents. The tumor can occur anywhere in the body but commonly presents in the extremities. Complete resection of tumor remains the most important modality of treatment and is directly related to prognosis. Neoadjuvant chemotherapy helps improve the resection rate of some unresectable tumors at diagnosis. Radiation therapy is primarily adopted for focal tumor control.


Asunto(s)
Neoplasias Óseas/secundario , Sarcoma/patología , Sarcoma/terapia , Neoplasias de los Tejidos Blandos/patología , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/patología , Neoplasias Óseas/terapia , Niño , China/epidemiología , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Extremidad Inferior , Masculino , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Periodo Posoperatorio , Pronóstico , Inducción de Remisión , Estudios Retrospectivos , Neoplasias de los Tejidos Blandos/terapia , Tasa de Supervivencia
6.
J Pharmacol Exp Ther ; 297(1): 50-6, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11259527

RESUMEN

Treatment of ovariectomized rats with dietary clofibrate caused a manyfold increase in the liver microsomal esterification of estradiol with fatty acids. The stimulatory effect of clofibrate administration on fatty acid esterification of estradiol by liver microsomes was paralleled in vivo by enhanced estradiol-induced increases in the formation of lobules in the mammary gland and by increased incorporation of bromodeoxyuridine into these lobules. In contrast to the stimulatory effect of clofibrate administration on the action of estradiol in the mammary gland, clofibrate administration had no effect on the uterotropic action of estradiol. These results indicate that clofibrate administration has a selective stimulatory effect on the hormonal action of estradiol in the mammary gland but not in the uterus.


Asunto(s)
Clofibrato/farmacología , Estradiol/farmacología , Hipolipemiantes/farmacología , Glándulas Mamarias Animales/efectos de los fármacos , Útero/efectos de los fármacos , Acilcoenzima A/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Estradiol/metabolismo , Femenino , Glándulas Mamarias Animales/patología , Microsomas Hepáticos/metabolismo , Ovariectomía , Ratas , Ratas Sprague-Dawley , Útero/patología
7.
Xenobiotica ; 31(12): 879-90, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11780762

RESUMEN

1. The metabolic O-methylation of several catechol-containing tea polyphenols by rat liver cytosolic catechol-O-methyltransferase (COMT) has been studied. 2. When (-)-epicatechin was used as substrate, its O-merthylation showed dependence on incubation time, cytosolic protein concentration, incubation pH and concentration of S-adenosyl-L-methionine. The O-methylation of increasing concentrations of (-)-epicatechin followed typical Michaelis-Menten kinetics, and the apparent Km and Vmax were 51 microM and 2882 pmol mg protein(-1) min(-1), respectively, at pH 7.4, and were 17 microM and 2093 pmol mg protein(-1) min(-1), respectively, at pH 10.0. 3. Under optimized conditions for in vitro O-methylation, (-)-epicatechin, (+)-epicatechin and (-)-epigallocatechin were rapidly O-methylated by rat liver cytosol. In comparison, (-)-epicatechin gallate and (-)-epigallocatechin gallate vere O-methylated at significantly lower rates under the same reaction conditions. catalysed O-methylation of (-)-epicatechin and (-)-epigallocatechin was inhibited in a concentration-dependent manner by S-adenosyl-L-homocysteine, a demethylated product of S-adenosyl-L-methionine. The IC50 was approximately 10 microM. 5. In summary, the results showed that several catechol-containing tea polyphenols were rapidly O-methylated by rat liver cytosolic COMT. These observations raise the possibility that some of the biological effects of tea polyphenols may be exerted by their O-methylated products or may result from their potential inhibition of the COMT-catalysed O-methylation of endogenous catecholamines and catechol oestrogens.


Asunto(s)
Catequina/análogos & derivados , Catequina/metabolismo , Catecol O-Metiltransferasa/metabolismo , Citosol/metabolismo , Flavonoides , Hígado/metabolismo , Té/química , Animales , Catecol O-Metiltransferasa/efectos de los fármacos , Citosol/efectos de los fármacos , Femenino , Concentración de Iones de Hidrógeno , Cinética , Hígado/efectos de los fármacos , Espectrometría de Masas/métodos , Metilación , Fenoles/metabolismo , Polímeros/metabolismo , Ratas , Ratas Sprague-Dawley , S-Adenosilhomocisteína/farmacología
8.
Steroids ; 65(9): 521-7, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10978731

RESUMEN

In recent years, development of potent inhibitors for estrogen sulfatases has become an actively pursued strategy for chemoprevention and/or chemotherapy of estrogen-dependent human breast cancers. We report here our findings that pregnenolone 16alpha-carbonitrile (PCN) is a potent inhibitor of estrone-3-sulfatase activity of rats and also humans. PCN inhibited in a concentration-dependent manner the desulfation of estrone-3-sulfate catalyzed by liver microsomal and nuclear fractions of female Sprague-Dawley rats. The inhibition of estrone-3-sulfatase activity in these two subcellular fractions showed a biphasic pattern, with a highly sensitive phase seen at 78 nM to 1.25 microm of PCN followed by a markedly less-sensitive phase at > 2.5 microm of PCN. Interestingly, several of PCN's structural analogs without a 16alpha-nitrile group showed little or no inhibitory effect on rat liver microsomal E(1)-3-sulfatase activity. Double-reciprocal analysis showed that the inhibition of rat liver microsomal E(1)-3-sulfatase activity by PCN was essentially competitive in nature. When microsomes from six human term placentas were tested for their E(1)-3-sulfatase activity, PCN showed a similar biphasic inhibition of placental E(1)-3-sulfatase. Likewise, several of its structural analogs showed little or no inhibitory effect on placental E(1)-3-sulfatase activity. Computational analysis of the D-ring structure of PCN and other structurally similar analogs used in the study suggests that the potent sulfatase-inhibiting activity of PCN may be partly due to its unique steric orientation and size of the 16alpha-nitrile group. This knowledge may be useful for the rational design of more potent steroidal inhibitors of E(1)-3-sulfatase by introducing an additional nitrile group to their C16alpha-position.


Asunto(s)
Carbonitrilo de Pregnenolona/farmacología , Sulfatasas/antagonistas & inhibidores , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Microsomas Hepáticos/enzimología , Modelos Moleculares , Conformación Molecular , Nitrilos/química , Nitrilos/farmacología , Placenta/enzimología , Placenta/ultraestructura , Embarazo , Carbonitrilo de Pregnenolona/análogos & derivados , Carbonitrilo de Pregnenolona/química , Ratas , Ratas Long-Evans , Ratas Sprague-Dawley , Electricidad Estática , Relación Estructura-Actividad , Fracciones Subcelulares/enzimología
9.
Drug Metab Dispos ; 28(9): 1024-30, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10950844

RESUMEN

In the present study, we evaluated the metabolic O-methylation of several catechol-containing tea polyphenols by human placental catechol-O-methyltransferase (COMT). (-)-Epicatechin, (+)-epicatechin, and (-)-epigallocatechin were good substrates for metabolic O-methylation by placental cytosolic COMT (150-500 pmol/mg of protein/min), but (-)-epicatechin gallate and (-)-epigallocatechin gallate were O-methylated at much lower rates (<50 pmol/mg of protein/min). When (-)-epicatechin was used as substrate, its O-methylation by human placental COMT showed dependence on incubation time, cytosolic protein concentration, incubation pH, and concentration of S-adenosyl-L-methionine (the methyl donor). Analysis of cytosolic COMT from six human term placentas showed that the O-methylation of increasing concentrations of (-)-epicatechin or (-)-epigallocatechin follows typical Michaelis-Menten kinetics, with K(m) and V(max) values of 2.2 to 8.2 microM and 132 to 495 pmol/mg of protein/min for (-)-epicatechin and 3.9 to 6.7 microM and 152 to 310 pmol/mg of protein/min for (-)-epigallocatechin, respectively. Additional analysis revealed that COMT-catalyzed O-methylation of (-)-epicatechin and (-)-epigallocatechin was strongly inhibited in a concentration-dependent manner by S-adenosyl-L-homocysteine (IC(50) = 3.2-5.7 microM), a demethylated product of S-adenosyl-L-methionine. This inhibition by S-adenosyl-L-homocysteine follows a mixed (competitive plus noncompetitive) mechanism of enzyme inhibition. In summary, several catechol-containing tea polyphenols are rapidly O-methylated by human placental cytosolic COMT. This metabolic O-methylation is subject to strong inhibitory regulation by S-adenosyl-L-homocysteine, which is formed in large quantities during the O-methylation of tea polyphenols.


Asunto(s)
Catecol O-Metiltransferasa/metabolismo , Flavonoides , Fenoles/metabolismo , Polímeros/metabolismo , Catequina/metabolismo , Cromatografía Líquida de Alta Presión , Citosol/enzimología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Concentración de Iones de Hidrógeno , Cinética , Espectrometría de Masas , Metilación/efectos de los fármacos , Placenta/enzimología , Embarazo , S-Adenosilhomocisteína/farmacología , Té/química
10.
Carcinogenesis ; 19(10): 1821-7, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9806165

RESUMEN

We evaluated the effects of a methanol extract from the leaves of the plant Rosmarinus officinalis L. (rosemary) on the metabolism and action of estradiol and estrone. Treatment of female CD-1 mice with 2% rosemary in AIN-76A diet for 3 weeks increased the liver microsomal 2-hydroxylation of estradiol and estrone by approximately 150%, increased their 6-hydroxylation by approximately 30% and inhibited the 16alpha-hydroxylation of estradiol by approximately 50%. Treatment of female CD-1 mice with 2% rosemary diet for 3 weeks also stimulated the liver microsomal glucuronidation of estradiol and estrone by 54-67% and 37-56%, respectively. In additional studies, feeding 2% rosemary diet to ovariectomized CD-1 mice for 3 weeks inhibited the uterotropic action of estradiol and estrone by 35-50% compared with animals fed a control diet. The results of this study showed that feeding female mice a 2% rosemary diet increased the liver microsomal oxidation and glucuronidation of estradiol and estrone and inhibited their uterotropic action.


Asunto(s)
Estrógenos/metabolismo , Lamiaceae/química , Microsomas Hepáticos/efectos de los fármacos , Extractos Vegetales/farmacología , Útero/fisiología , Animales , Dieta , Estrógenos/fisiología , Femenino , Glucuronatos/metabolismo , Hidroxilación , Ratones , Microsomas Hepáticos/metabolismo , NADP/metabolismo , Extractos Vegetales/administración & dosificación , Esteroide 16-alfa-Hidroxilasa
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