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PubMedDate not supplied

A case-control study on risk factors for pancreatic diseases in Kerala, India.

BACKGROUND/AIMS: We simultaneously conducted case-control studies, in Kerala of South India, on chronic calcific pancreatitis of the tropics (CCPT), pancreatic ductal adenocarcinoma (PDA) with CCPT, and PDA alone to assess similarity of and difference between their risk factors. METHODOLOGY: Cases with one of these diseases were identified at the Trivandrum Medical College (TMC) Hospital, in Kerala, from 1994 to 1996. Controls were selected from healthy hospital visitors of the TMC Hospital by individual age (within +/- 3 years) and sex-matched with the index case. Odds ratios and their 95% confidence intervals for potential risk factors were calculated. RESULTS: Frequent consumption of cassava was positively associated with the risk of PDA with CCPT. Heavy cigarette smoking and drinking large amounts of coffee and/or tea everyday were positively related to the risk of PDA alone. Frequent consumption of vegetables and/or fruits was correlated to the decreased risk of PDA alone. CONCLUSIONS: Risk factors as well as preventive factors seem to be different between PDA with CCPT and PDA alone. Further study is necessary, especially to clarify the prognostic factors which would induce pancreatic malignancy in patients with CCPT.

Adolescent↗
PubMed1999

[Headache and chronic sleep deprivation: an often missed relationship in children and also in adults].

Three children, two girls aged 9 and 13 years and a boy aged 9 years, and a man aged 22, presented with headache of migrainoid character. The complaints resolved after attention had been given to sleeping habits, notably problems with falling asleep. The literature on the relationship between lack of sleep and headache is scarce. In history-taking doctors often neglect sleeping customs. Yet awareness of this connection can provide the clue to a successful treatment of headache. In more than half the children with headache who are referred to the outpatient clinic of Neurology, a serious lack of sleep is a major contributing factor to the problems. One should strongly advise against use of coffee and Cola drinks at all times and of tea in the evening. Patients are urged to create a restful atmosphere about bedtime: taking a walk or a hot shower, being told a story and so on. They should not read in bed, watch TV or play computer games in the bedroom. Prescription of clonidine 0.025-0.075 mg in children before bedtime may be useful.

Adolescent↗
PubMedDate not supplied

Background factors affecting dental caries in permanent teeth of Finnish and Soviet children.

The aim of this study was to analyze the association between some general background factors and caries experience in two groups of Finnish children (from Helsinki and Kuopio) and Soviet children (Moscow and Leningrad). A total of 1187 schoolchildren, ages seven, nine and twelve years, were examined and information about their health habits was gathered by questionnaire. Questions included use of sweets, cakes, soft drinks, sugar-sweetened coffee and tea, toothbrushing frequency and mother's education. Except for age, the factors that explain caries experience clearly differ in Finnish and Soviet children.

Age Factors↗
PubMed1992

Weaning; a position statement.

1. Weaning is the process by which the milk fed infant is gradually accustomed to a varied diet. 2. The time at which weaning should commence should be signalled by the infant's being dissatisfied with a milk diet. While this tends to occur around five to six months of age, it may be later. 3. Appropriate foods to start weaning should be almost liquid in consistency, provide useful nutrients, and be of low allergenicity. 4. The aim is to achieve a diet based on family foods. These should conform to the criteria for a healthful diet, but should not be especially low in fat or rich in fibre. 5. In the earlier stages breast milk or formula remains the principal source of nutrition. Weaning foods should not be used in a way which discourages consumption of milks. 6. Water or diluted fruit juice may be used to assuage thirst, but should not supplant milk even in the later stages of weaning, since they contain no calcium or most other essential micronutrients. Tea and coffee are not suitable drinks for young children.

Age Factors↗
PubMed1993

Relation of caffeine intake to blood lipids in elderly women.

The relation of the consumption of caffeine from coffee, tea, and all caffeine-containing soft drinks (hereafter referred to as "cola") to blood lipid levels was studied in 1,035 white women ranging in age from 65 to 90 years (mean, 71.2 years) from October 1986 through October 1988. All study subjects were participants in the Pittsburgh, Pennsylvania, clinic of the Study of Osteoporotic Fractures. Fasting blood samples were tested for total cholesterol, triglycerides, apolipoproteins A-I and B-100, total high-density lipoprotein (HDL) cholesterol, and the HDL2 and HDL3 subfractions. Low-density lipoprotein (LDL) cholesterol was calculated using the Friedewald equation. Current consumption of coffee, tea, and cola was assessed by means of a self-administered personal habits questionnaire. Potential confounders, such as body mass index (weight (kg)/height (m)2), waist/hip ratio, smoking status, and alcohol intake were also measured for each woman. Analyses of variance and tests for mean differences revealed an inverse relation between the consumption of tea and apolipoprotein B-100 and a positive association between the consumption of cola and apolipoprotein B-100. Apolipoprotein A-I levels were found to be positively related to coffee consumption and negatively related to tea consumption. There was no consistent relation between caffeine consumption and total cholesterol, LDL cholesterol, total HDL cholesterol and its subfractions, or apolipoprotein B-100. Adjustment for potential confounders yielded no remaining significant associations between caffeine from any of the major beverage sources and any of the lipid fractions. In conclusion, the inconsistent relations between caffeine from various sources and blood lipids do not support a significant association of blood lipid levels with caffeine consumption in elderly women.

Aged↗
PubMed2005

Administration of green tea or caffeine enhances the disappearance of UVB-induced patches of mutant p53 positive epidermal cells in SKH-1 mice.

Irradiation of female SKH-1 hairless mice with UVB (30 mJ/cm2) twice a week for 10-20 weeks resulted in the formation of a large number of cellular patches (>8 adjacent cells/patch) that are recognized with an antibody (Pab240) which recognizes mutated but not wild-type p53 protein. These patches are not recognized by an antibody (Pab1620) to wild-type p53 protein. The patches, which are considered putative early cellular markers of the beginning of tumor formation, started appearing after 4-6 weeks of UVB treatment, and multiple patches were observed after treatment for 10 weeks. The number and size of the patches increased progressively with continued UVB treatment. Discontinuation of UVB for 4 weeks resulted in an 80-90% decrease in the number of these patches. The number of the remaining patches did not decrease any further but remained relatively constant for at least 4-9 weeks. Oral administration of green tea (6 mg tea solids/ml) or caffeine (0.4 mg/ml) as the sole source of drinking fluid during irradiation with UVB, twice a week for 20 weeks, inhibited UVB-induced formation of mutant p53 positive patches by approximately 40%. Oral administration of green tea (6 mg tea solids/ml) as the sole source of drinking fluid or topical applications of caffeine (6.2 micromol) once a day 5 days a week starting immediately after discontinuation of UVB treatment enhanced the rate and extent of disappearance of the mutant p53-positive patches. Topical applications of caffeine to the dorsal skin of mice pretreated with UVB for 20 weeks resulted in enhanced apoptosis selectively in focal basal cell hyperplastic areas of the epidermis (putative precancerous lesions), but not in areas of the epidermis that only had diffuse hyperplasia. Our studies indicate that the chemopreventive effect of caffeine or green tea may occur by a proapoptotic effect preferentially in early precancerous lesions.

Administration, Oral↗
PubMed1996

Inhibitory effects of tea catechins, black tea extract and oolong tea extract on hepatocarcinogenesis in rat.

Inhibitory effects of individual tea catechins ((--)-epicatechin, (--)-epigallocatechin, (--)-epicatechin gallate, (--)-epigallocatechin gallate), black tea extract and oolong tea extract on hepatocarcinogenesis were investigated. Male F344 rats received a single dose of diethylnitrosamine (200 mg/kg, i.p.), and thereafter phenobarbital (0.05%) was administered in the drinking water for a period of 6 weeks. Tea catechins, black tea extract or oolong tea extract were given during the entire experimental period, during only the initiation period or during only the promotion period. All four tea catechins, black tea extract and oolong tea extract (0.05 or 0.1%) significantly decreased the number and area of preneoplastic glutathione S-transferase placental form-positive foci in the liver. These results suggest that tea catechins, black tea extract and oolong tea extract have a chemopreventive action against hepatocarcinogenesis.

Animals↗
PubMed2004

LC-UV and LC-MS analysis of food and drink products containing kava.

A method for the determination of six kava lactones, methysticin, dihydromethysticin, kawain, dihydrokawain, yangonin and desmethoxyyangonin, in solid foods and beverages has been developed. Solid samples were prepared using methanol extraction, while beverages were extracted using a separate solid phase extraction (SPE) method. After sample preparation, the extracts were analysed using LC-UV or atmospheric pressure photoionization (APPI) LC-MS in the positive mode. Using the method, 10 beverage products, two chocolate products, three unbrewed tea products, three dietary supplements and a drink mix product were analysed. The results obtained using the LC-UV were comparable to those obtained using APPI-LC-MS for most products. Using the SPE method in conjunction with LC-MS, individual kava lactones were detected in drink products at ppb concentrations. Concentrations of total kava lactones ranged between 135-0.035 mg per serving in the food and beverage products tested and between 40-61 mg per serving for the dietary supplement products tested. Results of these analyses as well as extraction efficiency and reproducibility data are reported.

Beverages↗
PubMed2006

Differences in microbiological composition of saliva and dental plaque in subjects with different drinking habits.

Several foods have been shown to contain natural components (especially polyphenols) which display anti-adhesive properties against Streptococcus mutans, the aetiological agent responsible for dental crown caries, as well as inhibition of glucosyltransferases, which are the S. mutans enzymes involved in the synthesis of an adherent, water-insoluble glucan from sucrose. Other studies have demonstrated an in vitro action on oral plaque biofilm formation and desorption. This study evaluated whether the activity displayed in vitro by food compounds could affect the microbiological composition of saliva and dental plaque of subjects with a diet rich in these foods, comparing the results with those obtained from subjects with a different diet. The foods considered were: coffee, barley coffee, tea and wine. A total of 93 subjects were recruited into the study. Six samples of both plaque and saliva were collected from each subject at roughly one-monthly intervals. Total bacteria, total streptococci, S. mutans and lactobacilli counts were determined by culture in both saliva and dental plaque. The highest bacterial titres were recorded for the control population, while each drinking habit subgroup showed counts roughly one log lower than the controls. These differences in bacterial counts proved statistically significant (P<0.05). As far as dental plaque was concerned, while total counts did not significantly vary per mg of plaque in the subjects belonging to the different drinking habit subgroups, a significant decrease (P<0.05) was observed in those subjects drinking coffee, tea, barley coffee and wine when mutans streptococci and lactobacilli were evaluated. In several cases a more than one log decrease was observed. Plaque indices were also determined, and a significant (P<0.05) reduction in values was recorded in the subjects belonging the specific drinking habit subgroups compared to the control group. This study indicates that there is a correlation between consumption of specific foods and oral health in terms of reduced plaque deposition and lower counts of odontopathogens.

Adult↗
PubMed1994

Selective induction of rat hepatic CYP1 and CYP4 proteins and of peroxisomal proliferation by green tea.

Rats were exposed to freshly prepared aqueous extracts of green tea (2.5% w/v) as the sole source of drinking water for 4 weeks. Hepatic cytochrome P450 activity was determined using chemical probes, showing selectivity for particular isoforms, and by immunoblot analysis employing polyclonal antibodies. Exposure to green tea gave rise to increases in the O-demethylation of methoxyresorufin and, to a lesser extent, in the dealkylations of ethoxyresorufin and pentoxyresorufin. An increase was also seen in lauric acid hydroxylation but, in contrast, the N-demethylation of erythromycin was inhibited. p-Nitrophenol oxidase activity was unaffected by the same treatment. Immunoblot analysis revealed increases in the apoprotein levels of CYP1A2 and CYP4A1 following treatment with green tea. A significant increase was also noted in the CN(-)-insensitive palmitoyl CoA oxidation and this was paralleled by an increase in the levels of the peroxisomal trifunctional protein determined immunologically. Hepatic S9 and microsomal preparations from tea-treated animals were more effective than controls in activating 2-amino-3-methylimidazol[4,5-f]quinoline and 2-aminoanthracene to mutagens in the Ames test. When N-nitrosopyrrolidine served as the promutagen, tea did not influence its mutagenicity when isolated microsomes comprised the activation system but a significant inhibition was observed when hepatic S9 was used. The above findings are discussed within the context of the established anticarcinogenic and anti-mutagenic properties of green tea.

Animals↗
PubMed1997

Tea antioxidants in cancer chemoprevention.

In recent years, the concept of cancer chemoprevention has matured greatly. Significant reversal or suppression of premalignancy in several sites by chemopreventive agents appears achievable. This article summarizes experimental data on chemopreventive effects of tea polyphenols in different tumor bioassay systems. Tea (Camellia sinensis) is cultivated in about 30 countries, and is the most widely consumed beverage in the world. Three main commercial tea varieties--green, black, and oolong--are usually consumed, but most experimental studies demonstrating the antimutagenic and anticarcinogenic effects of tea have been conducted with water extract of green tea, or a polyphenolic fraction isolated from green tea (GTP). The majority of these studies have been conducted in a mouse skin tumor model system where tea is fed either as water extract through drinking water, or as purified GTP. GTP has been shown to exhibit antimutagenic activity in vitro, and inhibit carcinogen- as well as UV-induced skin carcinogenesis in vivo. Tea consumption has also been shown to afford protection against chemical carcinogen-induced stomach, lung, esophagus, duodenum, pancreas, liver, breast, and colon carcinogenesis in specific bioassay models. Several epicatechin derivatives (polyphenols) present in green tea have been shown to possess anticarcinogenic activity; the most active is (-)-epigallocatechin-3-gallate, which is also the major constituent of GTP. The mechanisms of tea's broad cancer chemopreventive effects are not completely understood. Several theories have been put forward, including inhibition of UV- and tumor promoter-induced ornithine decarboxylase, cyclo-oxygenase, and lipoxygenase activities, antioxidant and free radical scavenging activity; enhancement of antioxidant (glutathione peroxidase, catalase, and quinone reductase) and phase II (glutathione-S-transferase) enzyme activities; inhibition of lipid peroxidation, and anti-inflammatory activity. These properties of tea polyphenols make them effective chemopreventive agents against the initiation, promotion, and progression stages of multistage carcinogenesis.

Animals↗
PubMed2005

Protective effects of black tea extract on testosterone induced oxidative damage in prostate.

Since ancient times, antipyretic, anti-inflammatory, antimicrobial and antioxidative properties of tea have been recognized. Black tea (Camellia sinensis) contains a variety of polyphenolic ingredients including the theaflavins (TF), thearubigins (TG) and catechins. Components from black tea have been accounted to play an important role in scavenging free radicals generated by mutagens and carcinogens. Androgens are the key factors in either the initiation or progression of prostate cancer (PCA) by inducing oxidative stress. In the present set of investigations, the antioxidative potential of black tea extract against androgen mediated oxidative stress in male Wistar rats has been studied. Testosterone was given at a dose of 5 mg/kg b.w. subcutaneously, consecutively for 5 days. Prior to androgen administration, animals were kept on 0.5, 1.0 and 1.5% aqueous tea extract (ATE) as sole source of drinking fluid for 15 days. The prostate tissue was dissected out for biochemical analysis for antioxidant enzymes viz. catalase (CAT), superoxide dismutase (SOD), lipid peroxidation (LPO), glutathione-s-transferase (GST) and glutathione reductase (GR). The results revealed that testosterone administration induced the oxidative stress in rat prostate, however, in 0.5, 1.0 and 1.5% ATE supplemented groups, a significant protective effect of black tea against testosterone induced oxidative injury was recorded. Hence, the study reveals that constituents present in black tea impart protection against androgen induced oxidative injury that may result in development of prostate cancer.

Animals↗
PubMed1975

The effect of tea on iron absorption.

The effect of tea on iron absorption was studied in human volunteers. Absorption from solutions of FeCl3 and FeSO4, bread, a meal of rice with potato and onion soup, and uncooked haemoglobin was inhibited whether ascorbic acid was present or not. No inhibition was noted if the haemoglobin was cooked. The effect on the absorption of non-haem iron was ascribed to the formation of insoluble iron tannate complexes. Drinking tannin-containing beverages such as tea with meals may contribute to the pathogenesis of iron deficiency if the diet consists largely of vegetable foodstuffs.

Adult↗
PubMed1999

[Inhibitory effects of tea polyphenols and tea pigments on liver precancerous lesions in rats].

A liver precancerous model in rats was established with diethylnitorsamine(DEN) injected intraperitoneally as initiator and promoted by partial hepatectomy and injection of CCl4. The model was used to study the chemopreventive effect of tea polyphenols and tea pigments. A water solution of 0.1% tea polyphenols or tea pigments was given to Wistar rats as drinking water during the 56-day experiment period. A stable and sensitive early marker of liver cancer--GST-Pi positive foci or nodule was measured by a immunohistochemical method. Both tea polyphenols and tea pigments decreased the density and area of the GST-Pi foci. The expression of GST-Pi mRNA in chemical induced precancerous liver tissue was measured by Northern Blotting technique, and the expression of GST-Pi isoenzyme in liver tissue was detected by Western Blotting method. The results showed that both tea polyphenols and tea pigments effectively reduced the GST-Pi expression at both transcription and translation level. It is concluded that the inhibition of tea polyphenols and tea pigments on GST-Pi overexpression induced by chemical carinogen may be one of the mechanisms of their inhibition on the occurrence and progression of liver precancerous lesions in rats.

Animals↗
PubMed2003

Effect of green tea extract on cardiac hypertrophy following 5/6 nephrectomy in the rat.

BACKGROUND: Left ventricular hypertrophy commonly complicates chronic renal failure. We have observed that at least one pathway of left ventricular hypertrophy appears to involve signaling through reactive oxygen species (ROS). Green tea is a substance that appears to have substantial antioxidant activity, yet is safe and is currently widely used. We, therefore, studied whether green tea supplementation could attenuate the development of left ventricular hypertrophy in an animal model of chronic renal failure. METHODS: Male Sprague-Dawley rats were subjected to sham or remnant kidney surgery and given green tea extract (0.1% and 0.25%) or plain drinking water for the next 4 weeks. Heart weight, body weight, and cardiac Na-K-ATPase activity were measured at the end of this period. To further test our hypothesis, we performed studies in cardiac myocytes isolated from adult male Sprague-Dawley rats. We measured the generation of ROS using the oxidant sensitive dye dichlorofluorescein (DCF) as well as (3H)phenylalanine incorporation following exposure to cardiac glycosides with and without green tea extract. RESULTS: Administration of green tea extract at 0.25% resulted in attenuation of left ventricular hypertrophy, hypertension, and preserved cardiac Na-K-ATPase activity in rats subjected to remnant kidney surgery (all P < 0.01). In subsequent studies performed in isolated cardiac myocytes, both ouabain and marinobufagenin (MBG) were both found to increase ROS production and (3H)phenylalanine incorporation at concentrations substantially below their inhibitor concentration (IC) 50 for the sodium pump. Addition of green tea extract prevented increases in ROS production as well as (3H)phenylalanine incorporation in these isolated cardiac myocytes. CONCLUSION: Green tea extract appears to block the development of cardiac hypertrophy in experimental renal failure. Some of this effect may be related to the attenuation of hypertension, but a direct effect on cardiac myocyte ROS production and growth was also identified. Clinical studies of green tea extract in chronic renal failure patients may be warranted.

Animals↗
PubMed2000

The acute physiological and mood effects of tea and coffee: the role of caffeine level.

The objective of this study was to determine the effect of caffeine level in tea and coffee on acute physiological responses and mood. Randomised full crossover design in subjects after overnight caffeine abstention was studied. In study 1 (n = 17) the caffeine level was manipulated naturalistically by preparing tea and coffee at different strengths (1 or 2 cups equivalent). Caffeine levels were 37.5 and 75 mg in tea, 75 and 150 mg in coffee, with water and no-drink controls. In study 2 (n = 15) caffeine level alone was manipulated (water, decaffeinated tea, plus 0, 25, 50, 100, and 200 mg caffeine). Beverage volume and temperature (55 degrees C) were constant. SBP, DBP, heart rate, skin temperature, skin conductance, and mood were monitored over each 3-h study session. In study 1, tea and coffee produced mild autonomic stimulation and an elevation in mood. There were no effects of tea vs. coffee or caffeine dose, despite a fourfold variation in the latter. Increasing beverage strength was associated with greater increases in DBP and energetic arousal. In study 2, caffeinated beverages increased SBP, DBP, and skin conductance and lowered heart rate and skin temperature compared to water. Significant dose-response relationships to caffeine were seen only for SBP, heart rate, and skin temperature. There were significant effects of caffeine on energetic arousal but no consistent dose-response effects. Caffeinated beverages acutely stimulate the autonomic nervous system and increase alertness. Although caffeine can exert dose-dependent effects on a number of acute autonomic responses, caffeine level is not an important factor. Factors besides caffeine may contribute to these acute effects.

Adult↗