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1.
Med J Malaysia ; 77(Suppl 1): 16-22, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35899882

RESUMO

INTRODUCTION: Synacinn™ is a standardized polyherbal supplement for diabetes mellitus which is formulated from Andrographis paniculata, Curcuma xanthorrhiza, Cinnamomum zeylanicum, Eugenia polyantha, and Orthosiphon stamineous. MATERIALS AND METHODS: This study aimed to elucidate the antidiabetic potential of Synacinn™ on three specific actions, including 1) the insulin sensitivity and glucose transport on dexamethasone-induced insulin-resistance 3T3-L1 adipocytes, 2) the inhibitory capacity on postprandial enzyme activity (α-amylase and α-glucosidase), and 3) the inhibitory activity of hepatic DPP(IV) enzyme. RESULTS: Results showed that insulin resistance of 3T3-L1 adipocytes may be developed by prolonging the exposure of 1µg/ml of dexamethasone for >48 hours. The insulinresistance condition was minimized by the treatment of 10 µg/ml of Synacinn™ which significantly improved the insulin-stimulated glucose utilization by 10.6%. Meanwhile, insulin-stimulated glucose utilization in normal adipocytes was also attenuated by 9.2%. At the cellular level, Synacinn™ attenuated glucose utilization mainly by upregulating GLUT4 protein expression by 1.71 fold. Additionally, Synacinn™ is a potent inhibitor for the activity of α-amylase and α-glucosidase with IC50 of 0.467 mg/mL and 0.245 mg/mL, respectively. Synacinn™ also controlled the glycemic index through inhibition of hepatic DPP(IV) enzyme with IC50 of 1.11 mg/mL. CONCLUSION: Results suggested that Synacinn™ reduced diabetes mellitus through sensitizing the cellular glucose utilization, reducing the postprandial carbohydrate degradation, and inhibiting the hepatic DPP(IV) enzyme function.


Assuntos
Hipoglicemiantes , Resistência à Insulina , Dexametasona , Glucose , Humanos , Hipoglicemiantes/farmacologia , Insulina , Extratos Vegetais/farmacologia , Regulação para Cima , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
2.
Public Health ; 131: 103-11, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26715317

RESUMO

OBJECTIVES: Information about the quality of drinking water, together with analysis of knowledge, attitude and practice (KAP) analysis and health risk assessment (HRA) remain limited. The aims of this study were: (1) to ascertain the level of KAP regarding heavy metal contamination of drinking water in Pasir Mas; (2) to determine the concentration of heavy metals (Al, Cr, Cu, Fe, Ni, Pb, Zn and Cd) in drinking water in Pasir Mas; and (3) to estimate the health risks (non-carcinogenic and carcinogenic) caused by heavy metal exposure through drinking water using hazard quotient and lifetime cancer risk. METHODS: Information on KAP was collected using a standardized questionnaire. Heavy metal analysis of drinking water samples was performed using graphite furnace atomic absorption spectrophotometry. RESULTS: The population of Pasir Mas has good knowledge (80%), a less positive attitude (93%) and good practice (81%) towards heavy metal contamination of drinking water. The concentrations of heavy metals analysed in this study were found to be below the permissible limits for drinking water set by the Malaysian Ministry of Health and the World Health Organization. The HRA showed no potential non-carcinogenic and carcinogenic risks from the intake of heavy metal through drinking water. CONCLUSION: By investigating the quality of drinking water, KAP and HRA, the results of this study will provide authorities with the knowledge and resources to improve the management of drinking water quality in the future.


Assuntos
Água Potável/química , Água Potável/normas , Conhecimentos, Atitudes e Prática em Saúde , Metais Pesados/análise , Adulto , Idoso , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Medição de Risco , Inquéritos e Questionários , Adulto Jovem
3.
Analyst ; 139(22): 5999-6009, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25268849

RESUMO

Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) is ideally suited for the high-throughput analysis of small molecules in bodily fluids (e.g. saliva, urine, and blood plasma). A key application for this technique is the testing of drug consumption in the context of workplace, roadside, athlete sports and anti-addictive drug compliance. Here, we show that vertically-aligned ordered silicon nanopillar (SiNP) arrays fabricated using nanosphere lithography followed by metal-assisted chemical etching (MACE) are suitable substrates for the SALDI-MS detection of methadone and small peptides. Porosity, length and diameter are fabrication parameters that we have explored here in order to optimize analytical performance. We demonstrate the quantitative analysis of methadone in MilliQ water down to 32 ng mL(-1). Finally, the capability of SiNP arrays to facilitate the detection of methadone in clinical samples is also demonstrated.


Assuntos
Espectrometria de Massas/métodos , Silício/química , Líquidos Corporais/química , Humanos , Limite de Detecção , Microscopia Eletrônica de Varredura , Peptídeos/análise
4.
Int J Immunopathol Pharmacol ; 27(1): 45-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24674678

RESUMO

Breast cancer is estimated to be the most common malignancy affecting women in Iraq. The cancer antigen CA 15-3 has been used as a possible serum marker of occult and recurrent breast carcinoma, either alone or in combination with other tumor markers such as HER2/neu, that has evolved as a major classifier of invasive breast cancer and target of therapy for the disease. ELISA, used to evaluate serum levels of CA15-3 and immuno-histochemistry staining technique, was used to establish the HER2/neu status. The results of this study indicate an increased level of CA15-3 in breast cancer patients (29.02+/-1.79 IU/ml) as compared to both women with benign tumor and healthy controls (13.78+/-1.24 and 8.92+/-0.48 IU/ml, respectively), and that this increase is associated to advanced stages. Patients with HER2/neu positive malignancies show elevated serum CA15-3 (37.09+/-2.55 IU/ml), as well as patients who developed recurrence (40.75+/-2.11 IU/ml). Our data study suggests that higher levels of CA 15-3 would be a reliable prognostic marker as they were directly related to advanced stages and recurrence. In addition persistent elevation of CA 15-3 was associated to HER2/neu positivity in breast cancer patients.


Assuntos
Neoplasias da Mama/sangue , Mucina-1/sangue , Recidiva Local de Neoplasia/sangue , Receptor ErbB-2/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico
5.
Adv Mater ; 35(46): e2304072, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37498158

RESUMO

Permittivity of microscopic particles can be used as a classification parameter for applications in materials and environmental sciences. However, directly measuring the permittivity of individual microparticles has proven to be challenging due to the convoluting effect of particle size on capacitive signals. To overcome this challenge, a sensing platform is built to independently obtain both the geometric and electric size of a particle, by combining impedance cytometry and microwave resonant sensing in a microfluidic chip. This way the microwave signal, which contains both permittivity and size effects, can be normalized by the size information provided by impedance cytometry to yield an intensive parameter that depends only on permittivity. The technique allows to differentiate between polystyrene and soda lime glass microparticles-below 22 µm in diameter-with more than 94% accuracy, despite their similar sizes and electrical characteristics. Furthermore, it is shown that the same technique can be used to differentiate between normal healthy cells and fixed cells of the same geometric size. The technique offers a potential route for targeted applications such as environmental monitoring of microplastic pollution or quality control in pharmaceutical industry.

6.
Arch Razi Inst ; 77(5): 1593-1600, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-37123134

RESUMO

Cross-sectional studies have linked vitamin D deficiency and alteration of calcium levels to an increased incidence of type 2 diabetes and insulin resistance. This study investigated a possible correlation between blood vitamin D and calcium levels with insulin resistance and beta-cell dysfunction in type 2 diabetes, pre-diabetes, and healthy individuals. This cross-sectional study involved 300 participants. Participants were divided into three groups (n=100), type 2diabetic, prediabetic, and healthy. In order to measure insulin resistance and ß -cell function, the HOMA IR and HOMA B were assessed, respectively. Also, the other parameters such as serum 25(OH)D, blood insulin (FPI), glucose (FBS), HbA1c, and calcium were assessed in this study. In simple regression analysis, a high vitamin D level is linked to lower levels of FBS, HbA1c, Insulin, and HOMA IR, and higher levels of HOMA B. Calcium has a positive connection with FBS and HbA1c and a negative connection with insulin level and HOMAB. Hypovitaminosis D may substantially influence diabetes patients' glycemic dysregulation. "An increased incidence of type 2 diabetes has been related to a disruption in calcium homeostasis. All in all an increament in calcium levels may have a role in developing type 2 diabetes".


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Deficiência de Vitamina D , Cálcio/sangue , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobinas Glicadas , Insulina , Vitamina D/sangue , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Humanos
7.
ACS Appl Mater Interfaces ; 12(28): 31195-31204, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32551485

RESUMO

Novel doping agents and doping strategies are continually entering the market, placing a burden on analytical methods to detect, adapt, and respond to subtle changes in the composition of biological samples. Therefore, there is a growing interest in rapid, adaptable, and ideally confirmatory analytical methods for the fight against doping. Nanostructured silicon (nano-Si)-based surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) can effectively address this need, allowing fast and sensitive detection of prohibited compounds used in sport doping. Here, we demonstrate the detection of growth hormone peptides, anabolic-androgenic steroids, and narcotics at low concentrations directly from biological matrices. Molecular confirmation was performed using the fragmentation data of the structures, obtained with the tandem mass spectrometry capabilities of the SALDI instrument. The obtained data were in excellent agreement with those obtained using leading triple quadrupole liquid chromatography-mass spectrometry instruments. Furthermore, nano-Si SALDI-MS has the capacity for high-throughput analysis of hundreds of biological samples, providing opportunities for real-time MS analysis at sporting events.


Assuntos
Silício/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Dopagem Esportivo , Humanos , Nanoestruturas/química , Entorpecentes/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Detecção do Abuso de Substâncias/métodos
8.
Int J Tuberc Lung Dis ; 23(11): 1171-1177, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31718753

RESUMO

OBJECTIVE: To examine the associations between endotoxin and (1,3)-ß-glucan concentrations in office dust and respiratory symptoms and airway inflammation among 695 office workers in Malaysia.METHODS: Health data were collected using a questionnaire, sensitisation testing and measurement of fractional exhaled nitric oxide (FeNO). Indoor temperature, relative air humidity (RH) and carbon dioxide (CO2) were measured in the offices and settled dust was vacuumed and analysed for endotoxin and (1,3)-ß-glucan concentrations. Associations were analysed by two level multiple logistic regression.RESULTS: Overall, 9.6% of the workers had doctor-diagnosed asthma, 15.5% had wheeze, 18.4% had daytime attacks of breathlessness and 25.8% had elevated FeNO (≥25 ppb). The median levels in office dust were 11.3 EU/mg endotoxin and 62.9 ng/g (1,3)-ß-glucan. After adjusting for personal and home environment factors, endotoxin concentration in dust was associated with wheeze (P = 0.02) and rhinoconjunctivitis (P = 0.007). The amount of surface dust (P = 0.04) and (1,3)-ß-glucan concentration dust (P = 0.03) were associated with elevated FeNO.CONCLUSION: Endotoxin in office dust could be a risk factor for wheeze and rhinoconjunctivitis among office workers in mechanically ventilated offices in a tropical country. The amount of dust and (1,3)-ß-glucan (a marker of indoor mould exposure) were associated with Th2 driven airway inflammation.


Assuntos
Asma/epidemiologia , Poeira/análise , Dispneia/epidemiologia , Endotoxinas/análise , Rinite/epidemiologia , beta-Glucanas/análise , Adulto , Poluição do Ar em Ambientes Fechados/análise , Dióxido de Carbono/análise , Feminino , Humanos , Umidade , Modelos Logísticos , Malásia/epidemiologia , Masculino , Óxido Nítrico/análise , Sons Respiratórios/etiologia , Temperatura , Clima Tropical , Local de Trabalho
9.
Asia Pac J Public Health ; 19(3): 29-37, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18330402

RESUMO

A cross-sectional study was conducted to identify the relationship between blood lead concentration and nutritional status among primary school children in Kuala Lumpur. A total of 225 Malay students, 113 male and 112 female, aged 6.3 to 9.8 were selected through a stratified random sampling method. The random blood samples were collected and blood lead concentration was measured by a Graphite Furnace Atomic Absorption Spectrophotometer. The nutrient intake was determined by the 24-hour Dietary Recall method and Food Frequency Questionnaire. An anthropometric assessment was reported according to growth indices (z-scores of weight-for-age, height-for-age, and weight-for-height). The mean blood lead concentration was low (3.4 +/- 1.91 ug/dL) and was significantly different between gender. Only 14.7% of the respondents fulfilled the daily energy requirement. The protein and iron intakes were adequate for a majority of the children. However, 34.7% of the total children showed inadequate intake of calcium. The energy, protein, fat and carbohydrate intakes were significantly different by gender, that is, males had better intake than females. Majority of respondents had normal mean z-score of growth indices. Ten percent of the respondents were underweight, 2.8% wasted and 5.4% stunted. Multiple linear regression showed inverse significant relationships between blood lead concentration with children's age (beta = -0.647, p < 0.001) and per capita income (beta = -0.001, p = 0.018). There were inverse significant relationships between blood lead concentration with children's age (beta = -0.877, p = 0.001) and calcium intake (beta = -0.011, p = 0.014) and positive significant relationship with weight-for-height (beta = 0.326, p = 0.041) among those with inadequate calcium intake. Among children with inadequate energy intake, children's age (beta = -0.621, p < 0.001), per capita income (beta = -0.001, p = 0.025) and protein intake (beta = -0.019, p = 0.027) were inversely and significantly related with blood lead concentration. In conclusion, nutritional status might affect the children's absorption of lead and further investigation is required for confirmation.


Assuntos
Chumbo/análise , Chumbo/sangue , Estado Nutricional , Antropometria , Criança , Estudos Transversais , Feminino , Humanos , Malásia , Masculino , Rememoração Mental , População Urbana
10.
Food Chem ; 188: 46-50, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26041162

RESUMO

Little is known about the bioavailability of heavy metal contamination and its health risks after rice ingestion. This study aimed to determine bioavailability of heavy metal (As, Cd, Cu, Cr, Co, Al, Fe, Zn and Pb) concentrations in cooked rice and human Health Risk Assessment (HRA). The results found Zn was the highest (4.3±0.1 mg/kg), whereas As showed the lowest (0.015±0.001 mg/kg) bioavailability of heavy metal concentration in 22 varieties of cooked rice. For single heavy metal exposure, no potential of non carcinogenic health risks was found, while carcinogenic health risks were found only for As. Combined heavy metal exposures found that total Hazard Quotient (HQtotal) values for adult were higher than the acceptable range (HQTotal<1), whereas total Lifetime Cancer Risk (LCRTotal) values were higher than the acceptable range (LCRTotal values >1×10(-4)) for both adult and children. This study is done to understand that the inclusion of bioavailability heavy metal into HRA produces a more realistic estimation of human heavy metal exposure.


Assuntos
Disponibilidade Biológica , Metais Pesados/química , Oryza/química , Adulto , Criança , Humanos , Técnicas In Vitro , Medição de Risco , Poluentes do Solo/análise
11.
Singapore Med J ; 36(2): 230-1, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7676276

RESUMO

A 30-year-old Malay lady, with no previous or family history of bleeding, presented with severe gum bleeding 25 days post-partum. The factor VIII:c was 0.03 iu/ml with evidence of a slow-acting factor VIII inhibitor. Von Willebrand factor antigen (VWF:age) varied from less that 0.05 to 0.17 iu/ml, and there was absent ristocetin-induced platelet aggregation. Anti-nuclear and anti-DNA antibodies were present, but there were no other features of systemic lupus erythematosus. There was some clinical response to cryoprecipitate and tranexamic acid, and slight improvement with corticosteroid. Fifteen months later, the patient has no active bleeding problem, and her VWF-ag is increasing spontaneously. However, factor VIII:c is less than 0.01 iu/ml and her factor VIII inhibitor titre is still > 20 Bethesda units/ml.


Assuntos
Anticorpos Antinucleares/sangue , Fator VIII/antagonistas & inibidores , Hemorragia Gengival/etiologia , Transtornos Puerperais/etiologia , Doenças de von Willebrand/etiologia , Adulto , Fator VIII/uso terapêutico , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Agregação Plaquetária , Prednisolona/uso terapêutico , Ácido Tranexâmico/uso terapêutico , Fator de von Willebrand/análise
12.
Asia Pac J Public Health ; 7(1): 34-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8074944

RESUMO

The study was designed to determine if the activity pattern of pregnancy women on an intake of energy lower than that recommended will affect fetal growth. Subjects who volunteered were either attending public or private hospitals. Pregnant women in the "private" group were significantly older (p < 0.001) weighed somewhat less and significantly taller (p < 0.001) when compared to the "public" group. Differences in energy intake during the second and third trimesters between the "public" and "private" groups were small; 1608 +/- 334, 1726 +/- 271 kcal and 1627 +/- 367, 1778 +/- 260 kcal, respectively. However, daily activity patterns revealed that the "public" group was more active as reflected by the higher energy expenditure of 1412 +/- 74 kcal and 1578 +/- kcal during the second and third trimesters respectively. There was a significant difference (p < 0.01) in birth weight between the "public" and "private" groups; 2951 +/- 377 g and 3173 +/- 357 g respectively. This study indicates that energy intakes lower than recommended and sedentary lifestyles have no direct influence on birth weights of babies.


Assuntos
Atividades Cotidianas , Peso ao Nascer , Ingestão de Energia , Gravidez/fisiologia , Adulto , Metabolismo Energético , Feminino , Humanos , Recém-Nascido , Estilo de Vida , Estudos Longitudinais , Malásia
13.
Asia Pac J Public Health ; 12(2): 65-70, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11836921

RESUMO

The objective of this article is to study the influence of exposure and socio-economic variables on the blood lead level of Malaysian school children. Data on respirable lead and blood lead of 346 school children were obtained from Kuala Lumpur (urban), Kemaman (semi-urban) and Setiu (rural). Respirable lead and blood lead were highest for Kuala Lumpur (95 ng/m3 and 5.26 micrograms/dL) followed by Kemaman (27 ng/m3 and 2.81 micrograms/dL) and Setiu (15 ng/m3 and 2.49 micrograms/dL), and the differences were statistically significant. The percentage of school children with excessive blood lead of 10 micrograms/dL or greater was 6.36% overall, and highest for Kuala Lumpur (11.73%). Regression analyses show that urban children are at higher risk of exhibiting excessive blood lead levels. Kuala Lumpur's school children have a 25 times greater risk of having excessive blood lead levels when compared to Kemaman's and Setiu's school children. Respirable and blood lead were correlated (r = 0.999, p = 0.021). Urban school children acquire higher blood lead levels than their rural and semi-urban counterparts, even after controlling for age, sex, parents' education and income levels. In conclusion, it is time that lead in the Malaysian environment and population be monitored closely, especially its temporal and spatial variability. Only then can a comprehensive preventive strategy be implemented.


Assuntos
Poluentes Atmosféricos/sangue , Chumbo/sangue , População , Poluentes Atmosféricos/efeitos adversos , Análise de Variância , Criança , Exposição Ambiental/efeitos adversos , Exposição Ambiental/prevenção & controle , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Chumbo/efeitos adversos , Malásia , Masculino , Análise de Regressão , Fatores Socioeconômicos
14.
Int J Tuberc Lung Dis ; 18(7): 856-61, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24902566

RESUMO

OBJECTIVE: To identify the relationship between knowledge, attitude and perception regarding environmental tobacco smoke (ETS) and smoking among Malaysian adolescents living in states with complete or partial smoke-free legislation (SFL). METHODS: A total of 898 respondents aged 13-14 years were randomly selected from 21 secondary schools. The Malay version of the modified Global Youth Tobacco Survey questionnaire was used. Hierarchical logistic regression was performed in examining predictors of smoking attempt among adolescents. RESULTS: Participants exposed to ETS >5 h/day were more likely to have smoked compared to those exposed to ETS <1 h/day (OR 4.1, 95%CI 1.03-16.0). Living in a state with partial SFL was associated with a two-fold increase in self-reported smoking attempts (OR 1.95, 95%CI 1.10-3.43) compared to living in a state with complete SFL. Negative attitudes and perceptions towards smoking and ETS exposure were linked to lower smoking attempts in states with complete SFL. CONCLUSIONS: Adolescents with limited ETS exposure who lived in a state with complete SFL were less likely to attempt smoking compared to those exposed more regularly to ETS and living in a state with partial SFL. Preventing adolescents from becoming smokers is the key to reducing national prevalence rates in smoking. There is a need to implement comprehensive smoke-free legislation nationally across Malaysia.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Fumar/epidemiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Adolescente , Comportamento do Adolescente/psicologia , Feminino , Humanos , Modelos Logísticos , Malásia/epidemiologia , Masculino , Percepção , Fumar/psicologia , Prevenção do Hábito de Fumar , Inquéritos e Questionários
15.
Malays J Nutr ; 1(1): 31-40, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22692012

RESUMO

Food consumption of 50 female students in Universiti Kebangsaan Malaysia was recorded for 7 days. Foods and drinks most frequently consumed were selected for analysis of iron, zinc, copper and lead content. The mean daily intakes of energy, protein, carbohydrate and fat among the students are 6.5±1.4 MJ (1550±335 kcal), 59.8±18.5g, 227.1±54.6 g and 46.0±11.5 g respectively. This diet contributed 19.6-6.4 mg Fe, 7.0-2.0 mg Zn and 1.6-0.6 mg Cu per day which were lower than the Malaysian RDA for Fe and US RDA for Zn, while Cu is within the recommended range. The main sources of these minerals in the student's diet were rice, rice products, meat and animal products. Lead concentration in the diet (134±77 ug/day) is below the acceptable daily intake (ADI) value suggested by Codex Alimentarius Commission (1984). This study indicated concern regarding the low intake of the essential trace elements on long term basis among the students.

16.
Theor Appl Genet ; 82(4): 413-6, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24213255

RESUMO

Cytophotometric analyses were conducted to determine whether the DNA content of wheat callus varied by tissue culture medium or age of callus. Wheat,Triticum aestivum L. line PCYT-20, was cultured on three variations of the Murashige and Skoog (1962) growth medium. At the end of 2, 4, 6 and 8 weeks, samples were collected and prepared for Feulgen cytophotometry. Standards for the DNA measurements were readings from 100 telophase nuclei in wheat meristematic root tips. Amounts of DNA per nucleus present in telophase cells from callus grown on single-strength MS indicated that ploidy level increased 52%, 74% and 39%, respectively, over time from 2, 4, and 6 weeks as compared to the double-strength MS medium, and 29%, 60% and 32%, respectively, when coconut water was added to the single-strength MS culture medium. The shape of the mitotically-active cells in callus was more variable than in root tips cells. Callus grown on double-strength MS medium produced more shoots than callus grown on single-strength MS. Double-strength MS medium and, to a lesser extent, additional sucrose and organic nitrogen overcame the effects of 2,4-D on DNA amplification. Improved media may reduce the somaclonal variation induced by tissue culture.

17.
Int J Food Sci Nutr ; 47(5): 383-90, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8889623

RESUMO

Circulating zinc concentrations were measured in 73 healthy adult males and females 19-52 years of age who were volunteers for eight different metabolic studies at the University of California, Berkeley. The interindividual variation in the eight studies varied from 5 to 20%; the global coefficient of variation for all studies was 12 +/- 7% (mean +/- SD). The analysis of a reference plasma sample on six different days showed a mean coefficient of variation of 3.8%. Thus, only a small portion of the intraindividual variation is due to day-to-day analytical differences. There was no relationship between circulating zinc concentrations and age, height, or body mass index. Nor were there any significant differences due to gender. Information regarding dietary zinc and protein intakes was available from three-day weighed food intake records from 44 of the subjects. Plasma zinc concentrations were unrelated to the intake of either zinc or protein in those subjects. The results of this study show that the impact of age, gender, body size and dietary zinc or protein on circulating zinc concentrations are too small to be detected in the presence of the analytical and endogenous factors that influence plasma/serum zinc concentrations. Also, within a population of healthy adults, circulating zinc concentrations may vary by as much as 15%.


Assuntos
Zinco/sangue , Adolescente , Adulto , Negro ou Afro-Americano , Fatores Etários , Idoso , Estatura , Índice de Massa Corporal , Peso Corporal , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores Sexuais , População Branca
18.
J Synchrotron Radiat ; 2(Pt 5): 264-71, 1995 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16714827

RESUMO

Synchrotron-excited resonant-photoemission measurements at rare-earth 4d --> 4f and transition-metal 3p --> 3d thresholds have been carried out using a variety of complex cuprates and nickelates on stations 6.1 (grazing-incidence monochromator) and 6.2 (toroidal-grating monochromator) at the SRS CLRC Daresbury Laboratory. The systems studied are Nd(2)Ni(1 - x)Cu(x)O(4), La(2 - x)Sr(x)Ni(1- y)Fe(y)O(4 + delta) and Bi(2)Sr(2)Ca(1 - x)Y(x)Cu(2)O(8 + delta). A combination of EDC and constant-initial-state data is used to examine the 4f and 3d contributions to the valence-band density of states and their binding-energy positions relative to the Fermi energy. This allows the study of the valence states of the transition-metal ions and their modulation on doping. For La(2 - x)Sr(x)Ni(1 - y)Fe(y)O(4 + delta), this approach is used to infer a valence state of >/= 3.0 for Fe. In the case of Bi(2)Sr(2)Ca(1 - x)Y(x)Cu(2)O(8 + delta), the effect of Cu valence modulation on the 3p resonance is observed as x is varied. This is discussed in the light of controversy surrounding shifts in core-level photoemission with doping for this system.

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