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1.
Opt Lett ; 47(19): 4897-4900, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36181145

RESUMEN

Förster resonant energy transfer between atoms separated at a distance of a few nanometers has strong relevance to different properties of matter. In this work, the resonant energy transfer rate is derived from the electric potential in a system with one dipole interacting with a separated 2D plane of dipoles. It shows an R-2 (R: distance between dipole and 2D plane of dipoles) dependency on the distance of dipole layers, which is different from previous theoretical evaluations with an R-4 dependency. The electroluminescence (EL) properties are studied in different rare earth (Re: Tm, Tb, Ho, Yb, Er) distributed single atomic layer doped Al2O3 nanolaminates prepared by atomic layer deposition, in which the distance between single atomic layers of Re3+ is modulated at the atomic scale. Our theoretical results are consistent with the changes of EL intensity and decay time with the distance between the single atomic rare earth doping layers. This result is crucial for increasing the accuracy in biosensing and design of photonic materials.

2.
Mol Biol (Mosk) ; 54(6): 1037-1045, 2020.
Artículo en Ruso | MEDLINE | ID: mdl-33276367

RESUMEN

Brassica campestris L. is the important oil-bearing crop in China. Rapeseed cake is the main byproduct of rapeseed oil extraction. As the main active ingredient in rapeseed cake, sinapine has several important biological activities. Therefore, the inhibitory activity of sinapine on tyrosinase in vitro and its free radical-scavenging rate were determined. Tyrosinase activity in A-375 human melanocytes was also investigated and the effects of sinapine on the melanin content and its antioxidant effects on melanin biosynthesis were studied. The results showed that sinapine had significant antioxidant activity. Sinapine significantly inhibited A-375 human melanocytes in a dose-dependent manner. Sinapine inhibited melanin synthesis in A-375 cells by downregulating the mRNA and protein expression of TRP-1, TRP-2, and MITF factors. The results showed that rapeseed cake sinapine inhibited melanin production and could be used as a potential active ingredient in the development of whitening agents.


Asunto(s)
Brassica rapa/química , Colina/análogos & derivados , Melaninas/biosíntesis , Melanocitos/efectos de los fármacos , Línea Celular , China , Colina/aislamiento & purificación , Humanos
3.
J Viral Hepat ; 24(7): 589-598, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28130852

RESUMEN

Several noninvasive blood biomarkers have been established for the assessment of liver fibrosis in patients with chronic hepatitis B virus (HBV) infection, but their clinical performance remains inconclusive. Here, we compared the diagnostic performance of these biomarkers and developed a novel algorithm for assessing liver fibrosis. Six hundred and sixteen chronically HBV-infected and treatment-naïve patients who underwent liver biopsy were enrolled and randomly divided into training (N=410) and internal validation cohorts (N=206). One hundred and fifty-nine patients from another centre were recruited as an external validation cohort. Receiver operating characteristic (ROC) curves were used to analyse the performance of the gamma-glutamyltransferase-to-platelet ratio (GPR), red cell volume distribution width-to-platelet ratio (RPR), FIB-4 index, aspartate aminotransferase-to-platelet ratio index (APRI) and HBV DNA level against liver histology, and a novel algorithm was developed using the recursive partitioning and regression tree (RPART) method. In the training cohort, the area under the ROC curve of FIB-4 was significantly higher than that of APRI (P=.038) but was comparable to those of GPR, RPR and HBV DNA; however, the performance of the biomarkers was similar among the validation cohort. The established RPR-HBV DNA algorithm performed better in the training cohort than any individual blood biomarker, and the corresponding sensitivity, specificity, positive predictive value and negative predictive value were 63%, 90%, 72% and 80%, respectively. In the internal and external validation cohorts, the performance of the algorithm in assessing liver fibrosis was also superior to that of other biomarkers. These results suggest that the established RPR-HBV DNA algorithm might improve the diagnostic accuracy of liver fibrosis in treatment-naïve patients with chronic HBV infection, although additional studies are warranted to confirm these findings.


Asunto(s)
Biomarcadores/sangre , Pruebas Diagnósticas de Rutina/métodos , Hepatitis B Crónica/complicaciones , Cirrosis Hepática/diagnóstico , Adulto , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad
4.
Genet Mol Res ; 15(2)2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-27173276

RESUMEN

The aim of this study was to evaluate the association of GSTM1 null/present, GSTT1 null/present, and GSTP1 IIe105Val polymorphisms with the chemotherapy response and overall survival of advanced NSCLC. Two hundred and sixty-two patients with histologically confirmed advanced NSCLC (inoperable TNM stages IIIA, IIIB, and IV) were enrolled to this hospital-based study between May 2009 and May 2012. The GSTM1 null/present, GSTT1 null/present, and GSTP1 IIe105Val polymorphisms were genotyped by polymerase chain reaction coupled with restriction fragment length polymorphism. A logistic regression analysis revealed a correlation between the null genotype of GSTM1 and improved response to chemotherapy [odds ratio = 1.82; 95% confidence interval (CI) = 1.06-3.14]. Analyses with the Cox proportional hazards model also indicated that the null genotype of GSTM1 was associated with lower risk of death (hazard ratio = 0.40; 95%CI = 0.23-0.69). In conclusion, the null genotype of GSTM1 was found to be correlated with improved response to chemotherapy and lower risk of death in advanced NSCLC patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Glutatión Transferasa/genética , Neoplasias Pulmonares/genética , Polimorfismo de Longitud del Fragmento de Restricción , Anciano , Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , China , Cisplatino/uso terapéutico , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad
5.
Eur Rev Med Pharmacol Sci ; 28(17): 4226, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39297596

RESUMEN

The article "Influence of 12 weeks of basketball training on college students' heart function" by Z.-T. Yang, S.-W. Kim, Y.-S. Kim, X. Tang, H. Li, E.-L. Wang, published in Eur Rev Med Pharmacol Sci 2023; 27 (14): 6474-6479 DOI: 10.26355/eurrev_202307_33117-PMID: 37522658 has been retracted by the Editor in Chief. Due to third-party concerns about potential misquotations, the Editor-in-Chief has initiated an investigation to verify the validity of the allegations. The journal's assessment has shown that all references cited were not relevant to the text. The authors have been contacted to address the issues but only provided an updated list of references without a satisfactory explanation for the mistake. In light of the absence of a valid justification and the substantial misquotations throughout the text, the Editor-in-Chief has decided to retract the manuscript. The authors have been informed about the retraction but remained unresponsive. This article has been retracted. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/33117.

6.
Eur Rev Med Pharmacol Sci ; 27(14): 6474-6479, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37522658

RESUMEN

OBJECTIVE: This study aims to investigate the influence of 12 weeks of basketball training on college students' heart function. SUBJECTS AND METHODS: The subjects were 30 college male basketball players. Carry out 8-week interval training, monitor the training load and interval time of athletes, and strictly control the heart rate during the interval. Before and after training, we used safe and effective experimental instruments - without any damage to the athletes - to detect the relevant indicators of the athletes' physiological functions; hence we compared and analyzed the various indicators before and after training. RESULTS: The time domain indexes Root Mean Square of Successive Differences (RMSSD), Statistically Determined Spatial Drift (SDSD), percentage of NN50 in the total number of NN intervals (PNN50), and Standard Deviation of all NN intervals for all 5-min segment (SDNN) after training were significantly higher than those before training, and the differences were statistically significant (p<0.05). Average (Avag) and Statistically Determined Allocation Weights (SDAW) after training were significantly higher than those before training, the difference was statistically significant (p<0.05); Asymmetry (Asym) and Tension index (TI) were significantly lower than those before training, the difference was statistically significant (p<0.05), Application Information Index (ApInf) had no significant difference (p>0.05). There was no significant difference in shooting hit rate (p>0.05). The speed of the 8-character dribble in the whole field after training was significantly lower than that before training, and the differences were statistically significant (p<0.05). There was no significant difference in average jump height, maximum jump height, average time in the air, and best jump time in the air after training (p>0.05). For the test of athletes' explosive power, five vertical jumps in situ were selected for testing, and the jump height and time in the air of each vertical jump were counted to calculate the maximum and average values of five vertical jumps. The results showed that there was no significant change in the explosive force of the athletes' lower limbs after training. The reason may be that strength training needs to follow the principles of heavy load, specialization, exercise sequence and reasonable interval. The intermittent training method used during training is not specialized in strength training, and the reasonable interval of strength training was not considered in the training process. CONCLUSIONS: Intermittent training can increase the tension of the cardiac vagus nerve of college basketball players, increase the cardiac reserve function and the load that the heart can bear, so that the cardiac function can be improved well. It can improve the cardiopulmonary function and aerobic work ability of college basketball players. It can improve the adjustment ability of the heart, lungs, liver, and other organs of college basketball players. It also can increase the load intensity that the central nerve can bear and improve the function of the central nerve and autonomic nerve. The anti-fatigue ability of athletes can be improved. It can improve the speed quality of college basketball players.


Asunto(s)
Rendimiento Atlético , Baloncesto , Humanos , Masculino , Rendimiento Atlético/fisiología , Baloncesto/fisiología , Fuerza Muscular/fisiología , Estudiantes
7.
Cryo Letters ; 32(5): 402-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22020462

RESUMEN

To develop a procedure for cryopreservation of adult bovine testis tissue, the effects of dimethyl sulphoxide (DMSO), propylene glycol (PG), ethylene glycol (EG), and their concentrations (v/v), as well as different thawing temperatures, on the cell viability of bovine testis tissue after freezing/thawing were examined. The highest testicular cell viabilities came from the media containing DMSO (85.3 ± 1.2 percent), PG (82 ± 1.0 percent) and EG (83.4 ± 1.0 percent) at 10 percent concentration respectively. Using 10 percent DMSO gave significantly higher spermatogonia percentage (61.1 ± 1.2 percent, P < 0.001) than processing with 10 percent PG (54.3 ± 0.6 percent) or 10 percent EG (55 ± 1.8 percent) after differential plating. Thawing in water bath of 37 or 97-100 degree C also provided significantly higher viabilities (85.1 ± 1.0, 85 ± 1.0 percent, P < 0.01, respectively) and spermatogonia percentages (56.6 ± 2.0, 56.6 ± 2.6 percent, P < 0.01, respectively) than that thawing at 4C (23.4 ± 0.8 percent for total viability, 8.97 ± 1.0 percent for spermatogonia percentage). Collectively, 10 percent DMSO and thawing in 37-100 degree C water baths were appropriate for the cryopreservation of bovine testicular tissue and subsequent spermatogonia enrichment.


Asunto(s)
Criopreservación/métodos , Células Epiteliales/fisiología , Preservación de Semen/métodos , Epitelio Seminífero/fisiología , Espermatogonias/fisiología , Testículo/fisiología , Animales , Bovinos , Supervivencia Celular/efectos de los fármacos , Crioprotectores/farmacología , Dimetilsulfóxido/farmacología , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Glicol de Etileno/farmacología , Congelación , Masculino , Propilenglicol/farmacología , Epitelio Seminífero/citología , Epitelio Seminífero/efectos de los fármacos , Espermatogonias/citología , Espermatogonias/efectos de los fármacos , Testículo/citología , Testículo/efectos de los fármacos
8.
J Viral Hepat ; 16(9): 674-80, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19714778

RESUMEN

A recent genome-wide association study discovered that two polymorphisms, interferon (IFN) alpha receptor 2 (IFNAR-2) F8S and interleukin 10 receptor (IL10RB) K47E, were associated with susceptibility to hepatitis B virus (HBV) infection in Africa. Here, we reevaluate the effects of the two polymorphisms on HBV susceptibility in the Chinese Han population, and extended the study to look at their association with IFN response in chronic hepatitis B (CHB). We included 341 patients with CHB and 341 unrelated controls presenting with asymptotic HBV self-limited infection, who were well matched in age and sex. In the CHB group, 101 patients had been treated with peg-IFN-alpha-2a for 48 weeks and followed up for 24 weeks to determine the clinical response, resulting 34 individuals with sustained virological response (SVR) and 67 individuals with nonsustained response (NR). Subgroups in the CHB group were divided according to the viral loads, HBeAg and maternal HBsAg status. The association with the susceptibility to HBV infection was only observed for IL10RB K47E when we compared the individuals with persistent HBV infection through nonmaternal transmission to the controls with asymptomatic self-limited HBV infection. Further, we found that the IFNAR2-8SS genotype was associated with HBeAg negative patients (OR = 0.316, 95% CI: 0.121-0.825, P = 0.019) and that the IFNAR2-8F allele was associated with the risk to high viral loads (OR = 1.667, 95% CI: 1.148-2.420, P = 0.007). In addition, the IFNAR2-8FF genotype predisposed to higher MxA gene induction and correlated with sustained IFN response (OR = 0.348, 95% CI: 0.129-0.935, P = 0.036). Haplotype analysis based on polymorphisms of three single-nucleotide polymorphisms, MxA - 88 G/T, IFNAR-2 F8S and IL10RB K47E showed that the haplotype distribution was significantly different between the SVR and NR groups (P = 0.040). This study suggests that IFNAR2 may play an important role in determining IFN response and clinical phenotypes of HBV infection in the Chinese Han population.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B/tratamiento farmacológico , Hepatitis B/genética , Interferón-alfa/uso terapéutico , Subunidad beta del Receptor de Interleucina-10/genética , Polietilenglicoles/uso terapéutico , Polimorfismo Genético , Receptor de Interferón alfa y beta/genética , Adulto , Estudios de Casos y Controles , China , Susceptibilidad a Enfermedades , Femenino , Estudios de Seguimiento , Frecuencia de los Genes , Haplotipos , Antígenos de Superficie de la Hepatitis B/sangre , Humanos , Interferón alfa-2 , Masculino , Persona de Mediana Edad , Mutación Missense , Mutación Puntual , Proteínas Recombinantes , Resultado del Tratamiento , Carga Viral
9.
Eur Rev Med Pharmacol Sci ; 23(8): 3284-3290, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31081081

RESUMEN

OBJECTIVE: Recently, the role of long noncoding RNA (lncRNAs) in tumor progression has caught many attentions. In this research, lncRNA AFAP1-AS1 was studied to identify how it functioned in the progression of prostate cancer. PATIENTS AND METHODS: LncRNA AFAP1-AS1 expression was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) in both prostate cancer cells and tissue samples. In addition, to identify the function of AFAP1-AS1 on prostate cancer in vitro, cell proliferation, transwell assay, and Matrigel assay were conducted. Furthermore, by performing qRT-PCR and Western blot assay, the underlying mechanism was explored. RESULTS: The expression level of AFAP1-AS1 was significantly higher in prostate cancer samples than that in corresponding ones. Additionally, the cell proliferation, migration, and invasion capacities were inhibited after AFAP1-AS1 was knocked down in prostate cancer cells. Moreover, the mRNA and protein expressions of RBM5 were upregulated after AFAP1-AS1 was knocked down. Furthermore, the RBM5 expression level was negatively related to AFAP1-AS1 expression level in prostate cancer samples. CONCLUSIONS: AFAP1-AS1 acts as an oncogene in prostate cancer by enhancing cell metastasis and proliferation via suppressing RBM5, which might be a novel therapeutic strategy in treatment for prostate cancer.


Asunto(s)
Proteínas de Ciclo Celular/antagonistas & inhibidores , Movimiento Celular/genética , Proliferación Celular/genética , Proteínas de Unión al ADN/antagonistas & inhibidores , Neoplasias de la Próstata/genética , ARN Largo no Codificante/genética , Proteínas de Unión al ARN/antagonistas & inhibidores , Proteínas Supresoras de Tumor/antagonistas & inhibidores , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Masculino , Metástasis de la Neoplasia , Neoplasias de la Próstata/patología , ARN Interferente Pequeño/genética , Proteínas de Unión al ARN/genética , Transfección , Proteínas Supresoras de Tumor/genética
10.
J Natl Cancer Inst ; 81(2): 162-4, 1989 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-2909758

RESUMEN

Interviews with 564 patients with stomach cancer and 1,131 controls in an area of China where gastric cancer rates are high revealed a significant reduction in gastric cancer risk with increasing consumption of allium vegetables. Persons in the highest quartile of intake experienced only 40% of the risk of those in the lowest. Protective effects were seen for garlic, onions, and other allium foods. Although additional research is needed before etiologic inferences can be made, the findings are consistent with recent reports of tumor inhibition following administration of allium compounds in experimental animals.


Asunto(s)
Allium , Neoplasias Gástricas/prevención & control , Adulto , Anciano , Dieta , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
11.
Cancer Res ; 48(12): 3518-23, 1988 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-3370645

RESUMEN

A case-control investigation involving interviews with 564 stomach cancer patients and 1131 population-based controls was conducted to evaluate reasons for the exceptionally high rates of stomach cancer in Linqu, a rural county in Shandong Province in northeast China. Daily consumption of sour pancakes, a fermented indigenous staple, was associated with a 30% increase in risk. Risks of stomach cancer were also increased by 2- to 3-fold among persons with prior chronic gastritis or gastric ulcer, by 80% among those with stomach cancer in a family member, by 50% among men who smoked one or more packs of cigarettes/day, by 40% among those who preferred salty foods, and by 50% among families with moldy grain supplies. In contrast, risks tended to decrease in proportion to increasing consumption of fresh vegetables and fruits. This protective effect was more pronounced for vegetables, with those in the highest quartile of intake at less than one-half the risk of those in the lowest. Stomach cancer risks also declined with increasing dietary intake of carotene, vitamin C, and calcium, but not retinol. These findings provide leads to dietary factors that contribute to the high rates in Linqu, where stomach cancer is the leading cause of cancer and has not yet begun to decline as in other parts of the world.


Asunto(s)
Dieta , Neoplasias Gástricas/etiología , Adulto , Anciano , Ácido Ascórbico/administración & dosificación , Calcio de la Dieta/administración & dosificación , China , Conducta Alimentaria , Femenino , Gastritis Atrófica/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Factores de Riesgo , Fumar/efectos adversos , Cloruro de Sodio/efectos adversos , Verduras
12.
Sheng Li Xue Bao ; 44(1): 45-53, 1992 Feb.
Artículo en Zh | MEDLINE | ID: mdl-1598593

RESUMEN

Changes of beta-endorphin (beta-EP) and its mRNA in pituitary (P), hypothalamus (HT), lymphocytes (LC) and blood plasma (BP) during cold acclimation of SD male rats were studied by beta-EP mRNA dot blot, RP-HPLC and beta-EP radio-immunoassay (RIA). Experimental results showed: (1) After cold-exposure for 1 week pituitary beta-EP mRNA increased significantly with the appearance of stimulated cellular immune function. (2) beta-EP mRNA in hypothalamic immune center and peripheral LC increased when cold acclimation of animals was established for a cold exposure of 2 weeks (C2W). (3) From C2W onward, plasma beta-EP also continued to increase, indicating an augmented state of cellular immune function. As LC and plasma beta-EP product continued to show increase, pituitary beta-EP mRNA content recovered to control level from C2W onward possibly due to a feedback mechanism through LC-P-HT axis.


Asunto(s)
Aclimatación/fisiología , Frío , Hipotálamo/metabolismo , Linfocitos/metabolismo , Hipófisis/metabolismo , ARN Mensajero/metabolismo , betaendorfina/metabolismo , Animales , Masculino , ARN Mensajero/sangre , Ratas , Ratas Endogámicas , Bazo/citología , betaendorfina/genética
13.
Ultrasonics ; 48(8): 716-23, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18499207

RESUMEN

We study the transmission of electric energy through a circular cylindrical elastic shell by acoustic wave propagation and piezoelectric transducers. Our mechanics model consists of a circular cylindrical elastic shell with finite piezoelectric patches on both sides of the shell. A theoretical analysis using the equations of elasticity and piezoelectricity is performed. A trigonometric series solution is obtained. Output voltage and transmitted power are calculated. Confinement and localization of the vibration energy (energy trapping) is studied which can only be understood from analyzing finite transducers. It is shown that when thickness-twist mode is used the structure shows energy trapping with which the vibration can be confined to the transducer region. It is also shown that energy trapping is sensitive to the geometric and physical parameters of the structure.


Asunto(s)
Acústica/instrumentación , Electricidad , Transductores , Matemática , Vibración
14.
Renkou Yanjiu ; (2): 51-60, 1980 Jul.
Artículo en Zh | MEDLINE | ID: mdl-12159358

RESUMEN

PIP: China has historically valued and promoted population growth. Throughout the centuries, China's population development was characterized by 4 trends: 1) High birth rate caused by: a patriarchical system and ethical philosophy of ancestor worship which required a continuous family line, plus a system of private ownership where land was the primary means of production; a political philosophy that encouraged births and punished the lack of offspring; and a social attitude that promoted early marriages. 2) High death rate caused by: civil wars and violent struggles for power; natural disasters; plague; and infanticide of female babies. 3) A relatively slow rate of population growth resulting from high birth and death rates. 4) A relatively sparse population and abundant land prior to the Qing Dynasty (1644-1911). With the establishment of a new China, basic changes occurred in the social system and the means of production. For 30 years (1949-1979), China enjoyed peace, higher educational and public health standards, and was free from disastrous natural calamities, a consequence of which was a higher birth rate and lower death rate. Concurrently the thinking was that "the more people the better," so that population grew at an alarming rate. From 1949 to 1979, China's population increased by 422,150,000, compared with its previous 2000 years in which the population had increased nearly 400,000,000. In 1965, the national birth rate was 38.06/1000 compared with 19.95/1000 in 1944 for the 6 largest cities. The death rate in 1938 was 28.2/1000, but by 1965 it had dropped to 9.55/1000. The rate of natural population growth in 1965 was 28.51/1000 compared with the highest rate in China's history of 1957/1000 durint the Eastern Huan Dynasty (25-189 A.D.). Unfortunately there has been no conscious policy to plan population growth along with economic growth, so that population grew uncontrolled and people had less land per person than at any other time in China's history. Thus, China now advocates 1 child per couple.^ieng


Asunto(s)
Política , Dinámica Poblacional , Crecimiento Demográfico , Política Pública , Asia , Tasa de Natalidad , China , Demografía , Países en Desarrollo , Asia Oriental , Mortalidad , Población , Proyectos de Investigación
15.
IARC Sci Publ ; (105): 33-8, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1855874

RESUMEN

Research over the past several years in an area of Shandong, China, with one of the world's highest rates of gastric cancer, has yielded clues to the environmental determinants of this tumour. Interviews with 564 gastric cancer patients and 1131 population-based controls revealed increased risks associated with consumption of sour pancakes, a fermented staple unique to the area, in samples of which volatile N-nitrosamines have been detected. Lower risks were found among people who had a higher intake of fresh vegetables, including garlic and other Allium vegetables which contain constituents that can inhibit carcinogenesis by N-nitrosamines and other substances in experimental animals. A pilot study involving assays of urine and gastric juice from 60 individuals in a screening programme showed higher levels of N-nitrosoproline and of cis- and trans-N-nitroso-2-methylthiazolidine 4-carboxylic acid among persons with gastric dysplasia than in either normal controls or those with chronic atrophic gastritis. We are trying to characterize the transition and progression of precursor lesions to gastric cancer and to evaluate the role of dietary variables, nutrients, N-nitroso compounds and other factors in particular stages of the carcinogenic process.


Asunto(s)
Lesiones Precancerosas/etiología , Neoplasias Gástricas/etiología , China , Dieta , Humanos , Compuestos Nitrosos/toxicidad , Factores de Riesgo
16.
Sci Sin B ; 30(9): 941-5, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3445136

RESUMEN

In anther culture of Panax ginseng, its callus formation showed a wide adaptability to culture media. Large numbers of calli were induced on media exhibiting better effects of induction. Supplements of 5 mg 2,4-D/1 and 1 mg KT/1 to the media proved to be much effective. Regeneration of the whole plantlets from anther culture of Panax ginseng is usually quite difficult. During the past three years, however, sixteen of the 100 medium formulae tested were proved to be suitable. The formulae of MS + 0.5 mg BA/1 + 2 mg GA/1 + 1000 mg LH/1 + 3% sucrose were considered good and effective. A visibly differentiated body, which was light-milky white and later turned into a light green spot, was formed 40 days after the callus was transferred to the differentiation media. This body differentiated subsequently into buds, roots and, eventually, seedlings. The embryoid clones have been established in order to maintain its ability of continual differentiation into plantlets through successive culturings of many generations. The test-tube ginseng thus formed were transferred to regular flowerpots and grew well. Based upon chromosome examination of the callus cells and the root tips, we tentatively affirmed that the majority of these regenerated from anther of Panax ginseng were originated from pollen cells.


Asunto(s)
Panax/crecimiento & desarrollo , Plantas Medicinales , Métodos , Polen
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