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1.
Dis Esophagus ; 28(2): 164-71, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25714851

RESUMEN

The microsomal epoxide hydrolase 1 (EPHX1) Tyr113His and His139Arg polymorphisms have been reported to be associated with esophageal cancer (EC) risk, yet the results of these previous results have been inconsistent or controversial. The objective of this study was to explore whether the EPHX1 Tyr113His and His139Arg polymorphisms confer risk to EC. The relevant studies were identified through a search of PubMed, Excerpta Medica Database (Embase), Elsevier Science Direct, and Chinese Biomedical Literature Database until May 2013. The association between the EPHX1 Tyr113His and His139Arg polymorphisms and EC risk was pooled by odds ratios (ORs) together with their 95% confidence intervals (95%CIs). A total of eight case-control studies with 1163 EC patients and 1868 controls (seven studies for both Tyr113His and His139Arg polymorphisms, one study only for Tyr113His polymorphism) were eventually identified. We found no association between EPHX1 Tyr113His and His139Arg polymorphisms and EC risk in overall population (For Tyr113His: His vs. Tyr: OR = 1.05, 95%CI = 0.95-1.15, P = 0.379; His/His vs. Tyr/Tyr: OR = 1.04, 95%CI = 0.88-1.22, P = 0.208; His/Tyr vs. Tyr/Tyr: OR = 0.96, 95%CI = 0.80-1.15, P = 0.577; His/His vs. His/Tyr + Tyr/Tyr: OR = 1.10, 95%CI = 0.96-1.26, P = 0.164; His/His + His/Tyr vs. Tyr/Tyr: OR = 1.01, 95%CI = 0.90-1.12, P = 0.543. For His139Arg: Arg vs. His: OR = 1.04, 95%CI = 0.94-1.14, P = 0.465; Arg/Arg vs. His/His: OR = 1.06, 95%CI = 0.91-1.24, P = 0.470; Arg/His vs. His/His: OR = 1.03, 95%CI = 0.91-1.16, P = 0.673; Arg/Arg vs. Arg/His + His/His: OR = 1.04, 95%CI = 0.85-1.27, P = 0.708; Arg/Arg + Arg/His vs. His/His: OR = 1.02, 95%CI = 0.93-1.13, P = 0.617). In subgroup analysis based on ethnicity, significant association has been found in neither EPHX1 Tyr113His nor His139Arg polymorphism. The current meta-analysis suggests no evidence of association between the EPHX1 polymorphism and EC risk.


Asunto(s)
Epóxido Hidrolasas/genética , Neoplasias Esofágicas/genética , Polimorfismo Genético , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Humanos , Riesgo
2.
Clin Radiol ; 69(5): e191-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24631280

RESUMEN

AIM: To investigate the innervation pattern of extra-ocular muscles in patients with clinically diagnosed Duane's ocular retraction syndrome (DRS) using magnetic resonance imaging (MRI). MATERIALS AND METHODS: The study population consisted of 11 patients. Six patients had type I DRS (eight eyes), four patients had type II DRS (five eyes) and one patient had inverse DRS. Images were acquired using a Siemens 3 T MRI system. The type of DRS, corresponding innervation findings, and condition of the affected muscles were evaluated by two experienced neuroradiologists in consensus. RESULTS: All patients with clinically diagnosed DRS type I showed absence of the abducens nerve (CN6), hypoplasia of the superior oblique muscle (SOM), and aberrant innervation of lateral rectus muscle (LRM) by an extra branch of oculomotor nerve (CN3). All patients with type II DRS show dual-innervation of the LRM (by CN6 and an aberrant CN3 branch) and hypoplasia of SOM. The single patient with inverse DRS showed hypoplasia of CN3, the medial rectus muscle (MRM), the inferior rectus muscle (IRM), and the inferior oblique muscle (IOM). CONCLUSION: Each type of DRS has characteristic MRI appearances. Therefore, MRI is a useful diagnostic tool for the confirmation and classification of suspected cases of DRS.


Asunto(s)
Nervio Abducens/patología , Síndrome de Retracción de Duane/patología , Imagen por Resonancia Magnética , Músculos Oculomotores/patología , Nervio Oculomotor/patología , Nervio Abducens/anomalías , Adulto , Niño , Preescolar , China/epidemiología , Diagnóstico Diferencial , Síndrome de Retracción de Duane/genética , Síndrome de Retracción de Duane/fisiopatología , Femenino , Humanos , Masculino , Músculos Oculomotores/inervación , Nervio Oculomotor/fisiopatología
3.
Genet Mol Res ; 12(3): 4028-35, 2013 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-24089092

RESUMEN

Phosphoenolpyruvate carboxykinase 1 (PCK1), also named PEPCK-C, is a multiple-function gene that is involved in gluconeogenesis, glyceroneogenesis, reproduction, female fertility, and development of obesity and diabetes. How its many functions are regulated was largely unknown. Therefore, we investigated mRNA expression and possible splice variants of PCK1 by screening cDNA in nine tissues from Holstein bulls and cows. PCK1 mRNA was highly expressed in the liver, kidney, ovary and testis; expression levels were low in the heart, spleen, and lung tissues. Expression of this gene was not detected in skeletal muscle. This led to the discovery of five novel bovine splice variants, named PCK1-AS1-PCK1-AS5. In PCK1-AS1, 51 nucleotides in the interior of exon 2 were spliced out. In PCK1-AS2, exons 2 and 3 were altered by the alternative 3' and 5' splice sites, respectively. PCK1-AS3 was truncated from the 3' end of exon 2 to the 5' end of exon 4. In PCK1-AS4, exon 5 was completely spliced out. In PCK1-AS5, exons 5 and 6 and the 5' end of exon 7 were spliced out. These splice variants (PCK1-AS1-PCK1-AS5) potentially encoded shorter proteins (605, 546, 373, 246 and 274 amino acids, respectively), when compared to the complete protein (622 amino acids). Considering the functional domains of the PCK1 protein, it is likely that these splice variants considerably affect the function of this protein; alternative splicing could be one of the mechanisms by which the diverse functions of PCK1 are regulated.


Asunto(s)
Bovinos/genética , Fosfoenolpiruvato Carboxilasa/genética , Secuencia de Aminoácidos , Animales , China , Clonación Molecular , ADN Complementario , Exones , Femenino , Masculino , Datos de Secuencia Molecular , Músculo Esquelético/metabolismo , Fosfoenolpiruvato Carboxilasa/metabolismo , Conformación Proteica , ARN/genética , Empalme del ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Análisis de Secuencia de ADN
4.
Zhonghua Er Ke Za Zhi ; 61(8): 700-707, 2023 Aug 02.
Artículo en Zh | MEDLINE | ID: mdl-37528010

RESUMEN

Objective: To compare the application of China growth standard for children under 7 years of age (China standards) and World Health Organization child growth standards (WHO standards) in evaluating the prevalence of malnutrition in children aged 0-<6 years in China. Methods: The research data came from the national special program for science & technology basic resources investigation of China, named "2019-2021 survey and application of China's nutrition and health system for children aged 0-18 years". Multi-stage stratified random sampling was used to recruit 28 districts (regions) in 14 provinces, autonomous regions or municipalities across the country. Children (n=38 848) were physically measured and questionnaires were conducted in the guardians of the children. The indicators of stunting, underweight, wasting, overweight and obesity were evaluated by China standards and WHO standards respectively. Chi-square test was used to comparing the prevalence of each nutritional status between the two standards, as well as the comparison between the two standards by gender and age. Results: Among the 38 848 children, 19 650 were boys (50.6%) and 19 198 were girls (49.4%), 19 480 urban children (50.1%) and 19 368 rural children (49.9%). The stunting, underweight and wasting cases in the study population were 2 090 children (5.4%), 1 354 children (3.5%) and 1 276 children (3.3%) according to the China standards, and 1 474 children (3.8%), 701 children (1.8%) and 824 children (2.1%) according to the WHO standards, respectively; the above rates according to the China standards were slightly higher than those to the WHO standards (χ2=111.59, 213.14, and 99.99, all P<0.001). The overweight and obesity cases in the study population were 2 186 children (5.6%) and 1 153 children (3.0%) according to the China standards, and 2 210 children (5.7%) and 1 186 children (3.1%) according to the WHO standards, with no statistically significant differences (χ2=0.14 and 0.48, P=0.709 and 0.488, respectively). Compared to the results based on WHO standards, the China standards showed a lower prevalence of overweight and obesity in boys (χ2=14.95 and 5.85, P<0.001 and =0.016, respectively), and higher prevalence of overweight in girls (χ2=12.60, P<0.001); but there was no statistically significant differences in girls' obesity prevalence between the two standards (χ2=2.62, P=0.106). Conclusions: In general, the prevalence of malnutrition among children aged 0-<6 years based on China standards is slightly higher than that on WHO standards. To evaluate the nutritional status of children, it is advisable to select appropriate child growth standards based on work requirements, norms or research objectives.


Asunto(s)
Desnutrición , Estado Nutricional , Masculino , Femenino , Niño , Humanos , Preescolar , Sobrepeso/epidemiología , Delgadez/epidemiología , Obesidad/epidemiología , Desnutrición/epidemiología , Trastornos del Crecimiento/epidemiología , China/epidemiología , Prevalencia
5.
Genet Mol Res ; 11(3): 2909-16, 2012 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-22653646

RESUMEN

The complement system helps in the direct lysis of invading pathogens and modulates phagocytic, humoral and cellular immune responses. Complement 4 is a critical component in complement activity and protection against many bacterial pathogens because it is essential to classical and lectin activation pathways. We used reverse transcription and PCR to investigate alternative splicing and expression of the complement component 4 (C4A) gene in Chinese Holstein cattle. The PCR products were cloned and sequenced. A novel splice variant involving intron 10 was identified, which we named C4A-AS. To examine how C4A gene activity is affected by bovine mastitis, six Chinese Holstein cattle were divided into healthy (non-mastitic) and Staphylococcus aureus-induced mastitic groups. Real-time quantitative PCR (qRT-PCR) revealed that the C4A-complete and C4A-AS transcripts are expressed at significantly different levels in healthy cows, while there were no significant differences in the mastitic group (P = 0.257). Expression of C4A-AS increased significantly when mastitis developed. We also examined the expression of C4A-complete and C4A-AS in several tissues (liver, heart, spleen, lung, kidney, tongue, and muscle). The two transcripts were expressed in all of these tissues but there were no significant differences in expression between healthy and mastitic cows. We therefore conclude that the C4A-complete transcript is the main transcript under normal physiological conditions, while C4A-AS is augmented when mastitis develops.


Asunto(s)
Empalme Alternativo/genética , Bovinos/genética , Bovinos/inmunología , Complemento C4a/genética , Industria Lechera , Mastitis Bovina/genética , Mastitis Bovina/inmunología , Animales , China , Femenino , Mastitis Bovina/microbiología , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Staphylococcus aureus/fisiología
6.
Genet Mol Res ; 10(1): 340-52, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21365550

RESUMEN

Transferrin (Tf) is a ß-globulin protein that transports iron ions in mammalian cells. It contributes to innate immunity to microbial pathogens, primarily by limiting microbial access to iron. Thus, polymorphisms present in bovine Tf could potentially underlie inherited differences in mastitis resistance and milk production traits. We detected three novel single-nucleotide polymorphisms of the Tf gene in Chinese native cattle by screening for genetic variation of Tf in 751 individuals of three Chinese cattle breeds, namely China Holstein, Luxi Yellow and Bohai Black, using PCR-RFLP and DNA sequencing techniques. The three new SNPs, g.-1748G>A ss250608649, g.13942T>C ss250608650, and g.14037A>G ss250608651, had allele frequencies of 85.9, 86.3 and 92.5%, 64.5, 73.3 and 65.0%, and 67.6, 73.7 and 60.0%, respectively. SNP g.-1748G>A was located in the 5' flanking region of Tf. SNP g.14037A>G was located in intron 8 of Tf. SNP g.13942T>C, located in exon 8 of Tf, was a synonymous mutation (TTA > CTA), encoding a leucine (326 aa) in the Tf protein. Associations of the Tf SNPs with milk traits were also analyzed. Significant (P < 0.05) relationships among the Tf polymorphisms, somatic cell scores (SCS), and milk productive traits were observed. Cows with genotypes TT (g.13942T>C), GG (g.-1748G>A) and AG (g.14037A>G) had a lower SCS and higher protein levels and 305-day milk yield. Nineteen combinations of different haplotypes from the three SNPs were identified in Chinese Holstein cattle. The haplotype combination ATA/GCA, GCA/GCA and GCG/ GTA was dominant in cows with a lower SCS, a higher protein level and a higher 305-day milk yield, respectively. Moreover, the gene expression level of Tf was higher in mastitis-affected mammary tissues than in normal mammary tissues. These results suggest that the Tf gene affects milk production, as well as mastitis-resistance traits, in Chinese Holsteins.


Asunto(s)
Leche , Polimorfismo de Nucleótido Simple/genética , Transferrina/genética , Animales , Bovinos , Variación Genética/genética , Genotipo , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción/genética , Análisis de Secuencia de ADN
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(9): 1381-1384, 2020 Sep 10.
Artículo en Zh | MEDLINE | ID: mdl-33076588

RESUMEN

The central air conditioning ventilation system plays an important role in the air circulation of buildings such as centralized isolation medical observation points and general public buildings. In order to meet the requirements of COVID-19 epidemic prevention and control, Beijing Preventive Medicine Association organized Beijing CDC and other professional institutes to write up the group standard entitled "Technical specification for health risk investigation of central air conditioning ventilation system during the COVID-19 epidemic (T/BPMA 0006-2020)" . According to the particularity of central air conditioning ventilation system risk control during the outbreak of similar respiratory infectious diseases, based on current laws and regulations and the principle of scientific, practical, consistency and normative, 8 key points of risk investigations were summarized, which were the location of fresh air outlet, air conditioning mode, air return mode, air system, air distribution, fresh air volume, exhaust and air conditioner components. The contents, process, method, data analysis and conclusion of the investigation implementation were also defined and unified. It could standardize and guide institutions such as disease control and health supervision to carry out relevant risk managements, and provided solutions and technical supports for such major public health emergencies in city operations.


Asunto(s)
Aire Acondicionado/efectos adversos , Infecciones por Coronavirus/prevención & control , Epidemias , Diseño de Equipo/normas , Pandemias/prevención & control , Neumonía Viral/prevención & control , Ventilación/instrumentación , Aire Acondicionado/instrumentación , Beijing/epidemiología , COVID-19 , Infecciones por Coronavirus/epidemiología , Humanos , Neumonía Viral/epidemiología , Medición de Riesgo
8.
Anim Genet ; 38(6): 550-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17976215

RESUMEN

Twenty-seven domesticated yellow cattle breeds of China and three introduced cattle breeds were analysed by means of 30 microsatellite markers to determine the level of genetic variation within and among populations as well as the population structure. In all, 480 microsatellite alleles were observed across the 30 breeds with the mean number of alleles per locus of 9.093 for native breeds and 6.885 for the three introduced breeds. Mean F-statistics (0.08) for Chinese native cattle breeds implied that 92% of the total genetic variation was from genetic differentiation within each breed and 8% of the genetic variation existed among breeds. A phylogenetic tree was constructed based on Nei's genetic distances, and three clusters were obtained. According to the tree, the three introduced breeds were distinct from the 27 native breeds. The indigenous cattle breeds were divided into two clusters, one cluster including five humpless breeds and the other cluster containing 22 humped breeds. This study identifies multiple origins of yellow cattle of China from Bos taurus and Bos indicus. Furthermore, population structure analysis implies that there are possibly five independent original domestications for yellow cattle in China. Four of five origins were four different Bos indicus types, mainly in areas of the Chang Jiang, the Zhu Jiang River basin, the Yellow River and the Huai River basin. The other origin was for Bos taurus type of Mongolian descent, mainly located in Northwestern China, the Mongolian plateau and Northeastern China or north of the Great Wall.


Asunto(s)
Variación Genética , Repeticiones de Microsatélite , Alelos , Animales , Bovinos , China , Femenino , Marcadores Genéticos , Genotipo , Masculino , Filogenia
9.
J Med Genet ; 41(8): 585-90, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15286152

RESUMEN

BACKGROUND: Iodine deficiency is the commonest cause of preventable mental retardation (MR) worldwide. However, in iodine-deficient areas not everyone is affected and familial aggregation is common. This suggests that genetic factors may also contribute. Thyroid hormone (TH) plays an important role in fetal and early postnatal brain development. The pro-hormone T4 (3,3',5,5'-triiodothyronine) is converted in the brain to its active form, T3, or its inactive metabolite, reverse T3, mainly by the action of deiodinase type 2 (DIO2). METHODS: To investigate the potential genetic contribution of the DIO2 gene, we performed a case-control association study using three common SNPs in the gene (rs225014, rs225012, and rs225010) that were in strong linkage disequilibrium with each other. RESULTS: Single marker analysis showed a positive association of MR with rs225012 and rs225010. Particularly with rs255012 [corrected], CC [corrected] genotype frequency was significantly higher in MR cases than in controls (chi squared [corrected] = 9.18, p = 0.00246). When we compared the distributions of common haplotypes, we also found significant differences between mental retardation and controls in the haplotype combination of rs225012 and rs225010 (chi2 = 15.04, df 2, global p = 0.000549). This association remained significant after Bonferroni correction (p = 0.0016470). CONCLUSION: We conclude that allelic variation in the DIO2 gene may affect the amount of T3 available and in an iodine-deficient environment may partly determine overall risk of MR.


Asunto(s)
Discapacidad Intelectual/genética , Yoduro Peroxidasa/genética , Yodo/deficiencia , Adolescente , Niño , Preescolar , China/epidemiología , Femenino , Marcadores Genéticos/genética , Haplotipos/genética , Humanos , Discapacidad Intelectual/enzimología , Yodo/metabolismo , Desequilibrio de Ligamiento/genética , Masculino , Polimorfismo de Nucleótido Simple/genética , Triyodotironina/metabolismo , Yodotironina Deyodinasa Tipo II
10.
Artículo en Inglés | MEDLINE | ID: mdl-26221174

RESUMEN

RuPeng15 Powder (RPP15) is a herbal multicompound remedy that originates from traditional Tibetan medicine and possesses antigout, anti-inflammatory, and antihyperuricemic properties based on the traditional conceptions. The present study was undertaken to evaluate the therapeutic effect of PRP15 in rat gouty arthritis induced by monosodium urate (MSU) crystals. In the present study, we found that treatment with RPP15 (0.4, 0.8, and 1.2 g/kg) in rats with gouty arthritis induced by MSU crystals significantly attenuated the knee swelling. Histomorphometric and immunohistochemistry analyses revealed that MSU-induced inflammatory cell infiltration and the elevated expressions of nuclear transcription factor-κB p65 (NF-κB p65) in synovial tissues were significantly inhibited, and enzyme-linked immunosorbent assay (ELISA) result showed that MSU-induced high levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), and interleukin-8 (IL-8) in synovial fluid were reduced by treatment with RPP15 (0.4, 0.8, and 1.2 g/kg). We conclude that RPP15 may be a promising candidate for the development of a new treatment for gout and its activity of antigout may be partially related to inhibiting TNF-α, IL-1ß, IL-8, and NF-κB p65 expression in the synovial tissues.

11.
J Med Chem ; 31(2): 366-70, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3276891

RESUMEN

Quantitative structure-activity relationships for the inhibition of Escherichia coli (MB 1428) dihydrofolate reductase (DHFR) by 61 5-(substituted benzyl)-2,4-diaminopyrimidines are reported and analyzed. The 61 compounds include 17 congeners whose activities have not been previously reported, five of which have a 5'-substituent larger than a methoxy group. The correlation equations indicated that the molar refractivity (MR) values of the 5'-substituent, just as with the 3'- and 4'-substituents, contributed maximally at the value of 0.79 with no increment of binding for compounds with MR larger than 0.79 (which corresponds to a 5'-methoxy substitution). This experimental result is in agreement with the crystal structure of the Escherichia coli DHFR-trimethoprim complex, which shows a reasonably large trimethoprim-binding site. The inhibition of E. coli (MB 1428) DHFR by nine of the 17 new benzylpyrimidines is at lower concentrations than for trimethoprim. However, all 17 are much less potent than trimethoprim in inhibition of growth of E. coli (1515).


Asunto(s)
Escherichia coli/enzimología , Antagonistas del Ácido Fólico , Pirimidinas/farmacología , Sitios de Unión , Relación Estructura-Actividad , Trimetoprim/metabolismo
12.
J Med Chem ; 24(5): 538-44, 1981 May.
Artículo en Inglés | MEDLINE | ID: mdl-7017146

RESUMEN

In our previous publication (Blaney, J. M.; Dietrich, S. W.; Reynolds, M. A.; Hansch, C. J. Med. Chem. 1979, 22, 614), correlation equations were presented for the inhibition of bovine liver and Escherichia coli dihydrofolate reductase (DHFR) by 5-(substituted benzyl)-2,4-diaminopyrimidines. These equations brought out differences in the way these two enzymes interact with substituents, which explain the high selectivity of drugs like trimethoprim. We have tested and further developed these equations in this report. It is of particular interest that our previously published correlation equation for E. coli DHFR accurately predicted the potency of a commercial competitor of trimethoprim (tetroxoprim) now in clinical use. We believe that new and effective competitors for trimethoprim can be designed by means of the two correlation equations.


Asunto(s)
Escherichia coli/enzimología , Antagonistas del Ácido Fólico , Hígado/enzimología , Pirimidinas/síntesis química , Animales , Bovinos , Técnicas In Vitro , Cinética , Pirimidinas/farmacología , Relación Estructura-Actividad
13.
J Med Chem ; 34(1): 46-54, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1899453

RESUMEN

The inhibition constants (Kiapp) were obtained from the action of 68 2,4-diamino-5-(substituted-benzyl)pyrimidines on dihydrofolate reductase from an Escherichia coli strain MB 1428. Subsequently, these results were used to formulate appropriate quantitative structure-activity relationships (QSAR). Once again these equations emphasize the paramount importance of steric/dispersion factors in enhancing antibacterial potency. Hydrophobicity also plays a role, albeit a minor one. Comparisons with the QSAR obtained versus prokaryotic dihydrofolate reductase (DHFR) demonstrate subtle differences in binding behavior between meta and para substituents which may be effectively maximized in the design of more efficacious and selective antibacterial agents. The bacterial and avian QSAR equations can be used to calculate selectivity indices for trimethoprim, tetroxoprim, and two other specially designed 2,4-diamino-5-(substituted-benzyl)pyrimidines.


Asunto(s)
Diaminas/síntesis química , Antagonistas del Ácido Fólico , Pirimidinas/síntesis química , Diaminas/química , Diaminas/farmacología , Escherichia coli/enzimología , Cinética , Lacticaseibacillus casei/enzimología , Estructura Molecular , Unión Proteica , Pirimidinas/química , Pirimidinas/farmacología , Relación Estructura-Actividad
14.
J Med Chem ; 29(5): 621-6, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3701780

RESUMEN

The inhibition of chicken liver dihydrofolate reductase by a series of substituted benzylpyrimidines has been investigated. From the inhibition constants a quantitative structure-activity relationship has been formulated. This mathematical model is compared with molecular graphics models constructed from the X-ray crystallographic coordinates of trimethoprim and 5-(3,4-dimethoxy-4-isopropenylbenzyl)-2,4- diaminopyrimidine bound to the enzyme. There is good correspondence between the two types of models.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Antagonistas del Ácido Fólico , Hígado/enzimología , Animales , Pollos , Cristalografía , Matemática , Modelos Moleculares , Pirimidinas/farmacología , Relación Estructura-Actividad , Trimetoprim/farmacología , Difracción de Rayos X
15.
J Med Chem ; 32(8): 1895-905, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2502631

RESUMEN

Quantitative structure-activity relationships (QSAR) have been derived for the action of 68 5-(substituted benzyl)-2,4-diaminopyrimidines on dihydrofolate reductase (DHFR) from Lactobacillus casei and chicken liver. The QSAR are analyzed with respect to the stereographics models of the active sites of the enzymes and found to be in good agreement. Using these QSAR equations, we have attempted to design new trimethoprim-type antifolates having higher selectivity for the bacterial enzyme. The general problem of developing selective inhibitors is discussed.


Asunto(s)
Antagonistas del Ácido Fólico , Pirimidinas/farmacología , Animales , Fenómenos Químicos , Química , Pollos , Diseño de Fármacos , Lacticaseibacillus casei/enzimología , Hígado/efectos de los fármacos , Hígado/enzimología , Relación Estructura-Actividad , Difracción de Rayos X
16.
Phytochemistry ; 54(8): 875-81, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11014282

RESUMEN

Five stilbene dimers, gnetuhainins F-J, were isolated together with gnetulin, rhapontigenin, isorhapontigenin and gnetol from the lianas of Gnetum hainanense C. Y. Cheng. Their structures and stereochemistry have been established on the basis of spectral evidence, especially 2D NMR spectroscopic techniques.


Asunto(s)
Plantas/química , Estilbenos/aislamiento & purificación , Estructura Molecular , Análisis Espectral , Estilbenos/química
17.
J Emerg Med ; 17(2): 289-91, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10195489

RESUMEN

"Herbal Ecstacy" (sic) is an alternative drug of abuse usually containing both ephedrine and caffeine. Our literature search did not reveal any other reported cases of cardiovascular toxicity related to herbal "drugs of abuse." A case of cardiovascular toxicity following the ingestion of herbal ecstacy is presented. A 21-year-old male presented to the emergency department with an initial blood pressure of 220/110 mmHg and ventricular dysrhythmias after ingesting four capsules of herbal ecstacy. He was treated with lidocaine and sodium nitroprusside, and his symptoms resolved in 9 h. The pathophysiology and clinical course of ephedrine toxicity are discussed. Emergency physicians should consider ephedrine preparations in the differential diagnosis of patients presenting with a sympathomimetic toxidrome. Drugs of abuse containing "herbal" products can produce serious morbidity and mortality.


Asunto(s)
Sistema Cardiovascular/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/efectos adversos , Efedrina/efectos adversos , Drogas Ilícitas/efectos adversos , Trastornos Relacionados con Sustancias , Adulto , Arritmias Cardíacas/inducido químicamente , Presión Sanguínea/efectos de los fármacos , Urgencias Médicas , Humanos , Hipertensión/inducido químicamente , Masculino
18.
Zhonghua Zhong Liu Za Zhi ; 14(3): 213-5, 1992 May.
Artículo en Zh | MEDLINE | ID: mdl-1327697

RESUMEN

From June 1975 to June 1985, 423 patients with rectal carcinoma were randomized into 4 groups: 1. Surgery alone (S), 2. Pre-operative radiotherapy plus surgery (RS), 3. Surgery plus postoperative chemotherapy (SC), and 4. Preoperative radiotherapy plus surgery followed by postoperative chemotherapy (RSC). The 5-year survival rates of the combination groups: RS-34.4% (55/160); SC-47.5% (19/40); RSC-52.4%-(33/63) were all superior to that of S alone-28.8% (40/160). The difference between RSC and S alone was particularly significant (P less than 0.01). Further studies are warranted.


Asunto(s)
Neoplasias del Recto/terapia , Adenocarcinoma Mucinoso/mortalidad , Adenocarcinoma Mucinoso/patología , Adenocarcinoma Mucinoso/terapia , Adolescente , Adulto , Anciano , Carcinoma Intraductal no Infiltrante/mortalidad , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Intraductal no Infiltrante/terapia , Quimioterapia Adyuvante , Terapia Combinada , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Tasa de Supervivencia
19.
Zhonghua Zhong Liu Za Zhi ; 10(1): 61-2, 1988 Jan.
Artículo en Zh | MEDLINE | ID: mdl-3416701

RESUMEN

Twenty-seven patients with malignant lymphoma (14 Hodgkin's disease, 9 histiocytosarcoma, 2 plasmacytoma, 2 lympholeucosarcoma) were treated by Ailin-injection plus Chinese herbal medicine. The latter's composition and dose varied depending on the clinical manifestations. All the patients had stage III and IV lesions. The total remission rate was 70.37% (complete remission 13 patients, partial remission 6 patients, no remission 8 patients). In addition, we also studied the suppressive effect of Ailin on transplanted tumor in vivo (S-180). The suppression rates were 36.09%, 48.80%, 32.67% by three repetitions with an average of 39.18% (P less than 0.002). They were 37.25%, 35.29% on S37 with an average of 36.27% (P less than 0.005). They were 46.53%, 44.56%, 51.35%, 45.95% on Ehrlich ascites tumor cells with an average of 47.09% (P less than 0.001). The clinical and experimental studies suggest that Ailin-1 has no serious side effects and is well tolerated by patients with malignant lymphoma at moderate or advanced stages. No toxic reactions were observed at the clinical dose. In the above combination therapy, the Chinese herbal medicine has obvious supplementary effect in the treatment of the patients' cachexia and immuno-suppression.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Linfoma/tratamiento farmacológico , Adolescente , Adulto , Animales , Arsenicales/uso terapéutico , Carcinoma de Ehrlich/tratamiento farmacológico , Composición de Medicamentos , Femenino , Humanos , Masculino , Mercurio/uso terapéutico , Ratones , Persona de Mediana Edad , Sarcoma 180/tratamiento farmacológico , Sarcoma 37/tratamiento farmacológico
20.
Yao Xue Xue Bao ; 27(9): 711-6, 1992.
Artículo en Zh | MEDLINE | ID: mdl-1293946

RESUMEN

According to the quantitative structure-activity relationship studies of 3-pyrazolidinones with different substituent on positions 1 and 5 reported previously, the anticonvulsant activity is parabolically related with the total fragment constent (Fr hydrophobic parameter) of the 1 and 5 substituents of 3-pyrazolidion. The optimum Fr was about 5.6. Therefore, eleven new 5-substituted-3-pyrazolidinones have been synthesized. Pharmacological test showed that they are all potent anticonvulsant agents. Among them 1-n-butyl-5-(p-chlorophenyl)-3-pyrazolidinone was shown to be the most potent so far synthesized.


Asunto(s)
Anticonvulsivantes/síntesis química , Pirazoles/síntesis química , Pirazolonas , Anticonvulsivantes/química , Pirazoles/química , Relación Estructura-Actividad
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