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Context Millions of postmenopausal women use multivitamins, often believing that supplements prevent chronic diseases such as cancer and cardiovascular disease. Objective To examine associations between multivitamin use and risk of cancer, cardiovascular disease and mortality in postmenopausal women. Design, Setting and Participants 161,808 participants from the Women’s Health Initiative Clinical Trials (n=68,132 in three overlapping trials of hormone therapy, dietary modification and calcium-vitamin D) or Observational Study (n=93,676). Detailed data were collected on multivitamin use at baseline and follow-up time points. Study enrollment occurred between 1993–1998; women were followed for a median of 8.0 years in the clinical trials and 7.9 years in the observational study. Disease endpoints were collected through 2005. Outcome Measures Cancers of the breast (invasive), colon/rectum, endometrium, kidney, bladder, stomach, ovary and lung; cardiovascular disease (myocardial infarction, stroke, venous thrombosis); and total mortality. Results 41.5% of participants used multivitamins. After a median of 8.0 years of follow-up in the CT and 7.9 years in the OS, 9,619 cases of breast, colorectal, endometrium, kidney, bladder, stomach lung or ovary cancer; 8,751 CVD events and 9,865 deaths were reported. Multivariate-adjusted analyses revealed no association of multivitamins with risk of cancer (breast HR=0.98, 95%CI 0.91–1.05; colorectal HR = 0.99, 95% CI 0.88–1.11; endometrial HR = 1.05, 95%CI= 0.90–1.21; lung HR = 1.0, 95% CI=0.88–1.13; ovary HR = 1.07, 95%CI =0.88–1.29); CVD (MI HR= 0.96, 95%CI= 0.89–1.03; stroke HR = 0.99, 95%CI =0.91–1.07; VT HR = 1.05, 95%CI =0.85–1.29); or mortality (HR = 1.02, 95% CI=0.97–1.07). Conclusion After a median follow-up of 8.0 and 7.9 years in the CT and OS, respectively, the WHI cohorts provide convincing evidence that multivitamin use has little or no influence on the risk of common cancers, cardiovascular disease or total mortality in postmenopausal women. Clinical Trial Registration clinicaltrials.gov identifier: NCT00000611
Nineteen unselected patients with mild to moderate essential hypertension, whose average supine blood pressure after two months' observation on no treatment was 156/98 mm Hg, were advised not to add salt to food and to avoid sodium-laden foods. After 2 weeks of sodium restriction patients were entered into an 8-week double-blind randomised crossover study of 'Slow Sodium' (Ciba) versus slow sodium placebo. The mean supine blood pressure was 7.1 mm Hg (6.1%) lower in the fourth week of placebo than that in the fourth week of slow sodium (p less than 0.001). Urinary sodium excretion in the fourth week of slow sodium was 162 +/- 9 mmol/24 h and that in the fourth week of placebo was 86 mmol +/- 9 mmol/24 h (p less than 0.001). There was no difference in potassium excretion. These results suggest that moderate sodium restriction achieved by not adding salt and avoiding sodium-laden foods should, if not already, become part of the management of essential hypertension.
The ability of sorbic acid and its potassium and sodium salts to induce chromosome aberrations, sister chromatid exchanges (SCE) and gene mutations in cultured Chinese hamster V79 cells was examined. Sodium sorbate caused significant induction of chromosome aberrations and SCE, and also induced 6-thioguanine-resistant mutations in a dose-dependent manner. The clastogenic potency of sodium sorbate was found to be less than one hundredth of that of the potent clastogen N-methyl-N'-nitro-N-nitrosoguanidine. The induction of SCE by sodium sorbate was twice the control level, whereas that by methyl methanesulphonate, a potent inducer of SCE, was 14 times the control level. The mutagenic potency of sodium sorbate was less than one-tenth that of ethyl methanesulphonate, a potent inducer of mutation, when compared at an equitoxic level. Sorbic acid and its potassium salt induced chromosome aberrations, but only at the highest doses tested. These compounds also induced 1.2 times the control level of SCE, but neither compound induced 6-thioguanine-resistant mutations. The cytogenetic activity of sodium sorbate was concluded not to be due to the effect of osmotic pressure or an impurity. These results indicate that sodium sorbate is a genotoxic agent, although its potency seems to be weak, and that sorbic acid and potassium sorbate are less genotoxic than the sodium salt.
An analytical method was developed for the simultaneous quantification of serotonin, melatonin, trans- and cis-piceid, and trans- and cis-resveratrol using reversed-phase high performance liquid chromatography coupled to mass spectrometry (HPLC-MS) with electrospray ionization (ESI) in both positive and negative ionization modes. HPLC optimal analytical separation was achieved using a mixture of acetonitrile and water with 0.1% formic acid as the mobile phase in linear gradient elution. The mass spectrometry parameters were optimized for reliable quantification and the enhanced selectivity and sensitivity selected reaction monitoring mode (SRM) was applied. For extraction, the direct analysis of initial methanol extracts was compared with further ethyl acetate extraction. In order to demonstrate the applicability of this analytical method, serotonin, melatonin, trans- and cis-piceid, and trans- and cis-resveratrol from 24 kinds of commonly consumed fruits were quantified. The highest serotonin content was found in plantain, while orange bell peppers had the highest melatonin content. Grape samples possessed higher trans- and cis-piceid, and trans- and cis-resveratrol contents than the other fruits. The results indicate that the combination of HPLC-MS detection and simple sample preparation allows the rapid and accurate quantification of serotonin, melatonin, trans- and cis-piceid, and trans- and cis-resveratrol in fruits. Copyright © 2011 Elsevier B.V. All rights reserved.
A number of natural compounds with inhibitory effects on tumorigenesis have been identified from our diet. Several studies have documented the cancer-preventive activity of a significant number of isothiocyanates (ITCs), the majority of which occur in plants, especially in Cruciferous vegetables. The most characterized ITC is sulforaphane (SFN). SFN has received a great deal of attention because of its ability to simultaneously modulate multiple cellular targets involved in cancer development, including: (i) DNA protection by modulating carcinogen-metabolizing enzymes and blocking the action of mutagens; (ii) inhibition of cell proliferation and induction of apoptosis, thereby retarding or eliminating clonal expansion of initiated, transformed, and/or neoplastic cells; (iii) inhibition of neoangiogenesis, progression of benign tumors to malignant tumors, and metastasis formation. SFN is therefore able to prevent, delay, or reverse preneoplastic lesions, as well as to act on cancer cells as a therapeutic agent. Taking into account this evidence and its favorable toxicological profile, SFN can be viewed as a conceptually promising agent in cancer prevention and/or therapy.
PURPOSE: Protecting the lens against oxidative stress is of great importance in delaying the onset of cataract. Isothiocyanates, such as sulforaphane (SFN), are proposed to provide cytoprotection against oxidative stress. We therefore tested the ability of SFN to perform this role in lens cells and establish its ability to delay the onset of cataract. METHODS: The human lens epithelial cell line FHL124 and whole porcine lens culture systems were used. The ApoTox-Glo Triplex Assay was used to assess FHL124 cell survival, cytotoxicity, and apoptosis. The MTS assay was used to assess cell populations. To determine levels of DNA strand breaks, the alkaline comet assay was performed and quantified. Lactate dehydrogenase levels in the medium were evaluated to reflect cell damage/death. To assess level of gene expression, an Illumina whole-genome HT-12 v4 beadchip was used. Protein expression was determined by Western blot and immunocytochemistry. RESULTS: Exposures of 30 μM H2O2 to FHL124 cells caused a reduction in cell viability and increased cytotoxicity/apoptosis; these effects were significantly inhibited by 24-hour pretreatment with 1 μM SFN. In addition, 1 μM SFN significantly reduced H2O2-induced DNA strand breaks. When applied to cultured porcine lenses, SFN protected against H2O2-induced opacification. Illumina whole-genome HT-12 v4 beadchip microarray data revealed eight genes upregulated following 24-hour exposure to 1- and 2-μM SFN, which included NQO1 and TXNRD1. This pattern was confirmed at the protein level. Nrf2 translocated to the nucleus in response to 0.5- to 2.0-μM SFN exposure CONCLUSIONS: The dietary component SFN demonstrates an ability to protect human lens cells against oxidative stress and thus could potentially delay the onset of cataract.
OBJECTIVES: To determine seminal antioxidant capacity, oxidative stress markers, and their association with semen quality as oxidative stress is considered to be a major etiological factor in male infertility. SUBJECTS AND METHODS: Semen samples were obtained from 138 men and categorized on the basis of sperm count, motility, and morphology. Seminal oxidative and antioxidant markers are as follows: lipid peroxidation (LPO), protein carbonyls (PC), superoxide dismutase (SOD), catalase (CAT), thiols, and ascorbic acid were determined. RESULTS: Sperm count significantly correlated positively with progressive sperm motility and normal morphology. Sperm count and normal morphology showed significant negative correlation with LPO and PC. Sperm count and progressive motility showed significant positive relationship with SOD. The SOD, CAT, and thiols positively whereas LPO and PC negatively associated with elevated sperm count. CONCLUSION: Insufficient antioxidant enzymes and increased oxidative stress may attribute to the risk of declining semen quality and hence protective role for antioxidant enzymes against the oxidative damage cannot be ruled out. Copyright © 2010 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
The sap of Croton lechleri Muell.-Arg (Euphorbiaceae), called Dragon's blood, is used in folk medicine as a cicatrizant, anti-inflammatory and to treat cancer. In this research, the antioxidant activity of Croton lechleri sap was evaluated against the yeast Saccharomyces cerevisiae and against maize plantlets treated with the oxidative agents apomorphine and hydrogen peroxide. The mutagenic activity of the sap was also analyzed using the Salmonella/microsome assay (Salmonella typhimurium TA97a, TA98, TA100, TA102, TA1535) and in cells of the yeast Saccharomyces cerevisiae. The results showed that Croton lechleri sap possesses significant antioxidant activity against the oxidative damages induced by apomorphine in Saccharomyces cerevisiae under all the conditions studied. However, in the case of hydrogen peroxide, antioxidant activity of the sap was detected only in cells in the stationary phase of growth. The sap was also able to protect cells of the maize plantlets from the toxic effect of apomorphine. This sap showed mutagenic activity for strain TA1535 of Salmonella typhimurium in the presence of metabolic activation and a weak mutagenic activity for strain TA98. These strains detect base pair substitutions and frameshift mutations, respectively. Mutagenicity was also observed in a haploid Saccharomyces cerevisiae strain XV185-14c for the lys1-1, his1-7 locus-specific reversion and hom3-10 frameshift mutations.
Aim: To review special safety topics associated with sildenafil and to document the tolerability of 50- and 100-mg doses, overall and by age, in men with erectile dysfunction (ED). Methods: Data were collated from 67 double-blind placebo-controlled (DBPC) trials (> 14,000 men) conducted by the manufacturer and from the manufacturer’s postmarketing safety database (39,277 patients). The DBPC data were stratified by dose, starting dose and age (≥ 65 and ≥ 75 years). Special safety topics included cardiovascular risk, priapism, non-arteritic anterior ischaemic optic neuropathy (NAION), impaired renal and hepatic function, drug interactions (i.e. nitrates, cytochrome P3A4 inhibitors, other ED therapies and α-blockers) and incorrect use. Results: Sildenafil was well tolerated at a dose of 50 or 100 mg in men with ED, overall, in those aged ≥ 65 years, and in those aged ≥ 75 years. Analyses of the databases did not reveal any causal link between sildenafil and cardiovascular events, or any new safety risks relating to cardiovascular events, priapism, NAION, hearing loss or drug interactions. In the small number of men with moderate impairment of renal function or hepatic function who were treated with sildenafil in DBPC trials, the safety profile was similar to that in men with no impairment of renal or hepatic function. Overdose with sildenafil was rare in the ED population. No new safety issues, emerging trends or adverse reactions were identified in conjunction with overdose, dependence, abuse or misuse. Conclusion: This collated review confirms generally the good tolerability and established safety profile of sildenafil 50 and 100 mg in men with ED and reveals no new safety issues.
Sulforaphane [1-isothiocyanate-(4R)-(methylsulfinyl)butane] is a natural dietary isothiocyanate produced by the enzymatic action of the myrosinase on glucopharanin, a 4-methylsulfinylbutyl glucosinolate contained in cruciferous vegetables of the genus Brassica such as broccoli, brussel sprouts, and cabbage. Studies on this compound is increasing because its anticarcinogenic and cytoprotective properties in several in vivo experimental paradigms associated with oxidative stress such as focal cerebral ischemia, brain inflammation, intracerebral hemorrhage, ischemia and reperfusion induced acute renal failure, cisplatin induced-nephrotoxicity, streptozotocin-induced diabetes, carbon tetrachloride-induced hepatotoxicity and cardiac ischemia and reperfusion. This protective effect also has been observed in in vitro studies in different cell lines such as human neuroblastoma SH-SY5Y, renal epithelial proximal tubule LLC-PK1 cells and aortic smooth muscle A10 cells. Sulforaphane is considered an indirect antioxidant; this compound is able to induce many cytoprotective proteins, including antioxidant enzymes, through the Nrf2-antioxidant response element pathway. Heme oxygenase-1, NAD(P)H: quinone oxidoreductase, glutathione-S-transferase, gamma-glutamyl cysteine ligase, and glutathione reductase are among the cytoprotective proteins induced by sulforaphane. In conclusion, sulforaphane is a promising antioxidant agent that is effective to attenuate oxidative stress and tissue/cell damage in different in vivo and in vitro experimental paradigms. Copyright © 2010 Elsevier GmbH. All rights reserved.
Longevity, lifespan, cancer, cellular transformation, energy, calorie restriction, diabetes--what can tie together such a diversity of hot topics in biomedical research? Emerging findings suggest that the answer lies in understanding the functions of the recently discovered family of proteins known as Sirtuins. Barcelona hosted the first scientific meeting completely focused on these evolutionary conserved protein deacetylases, bringing together experts in the biochemistry to cellular biology, mice models, drug targeting and pathophysiology of these molecules. Their work, summarized here, establishes the Sirtuins as major players in cellular homeostasis and human diseases that act through a whole range of biochemical substrates and physiological processes. Undoubtedly, this is an increasingly expanding field that it is here to stay and growth.
Titanium dioxide is a common additive in many food, personal care, and other consumer products used by people, which after use can enter the sewage system, and subsequently enter the environment as treated effluent discharged to surface waters or biosolids applied to agricultural land, incinerated wastes, or landfill solids. This study quantifies the amount of titanium in common food products, derives estimates of human exposure to dietary (nano-) TiO2, and discusses the impact of the nanoscale fraction of TiO2 entering the environment. The foods with the highest content of TiO2 included candies, sweets and chewing gums. Among personal care products, toothpastes and select sunscreens contained 1% to >10% titanium by weight. While some other crèmes contained titanium, despite being colored white, most shampoos, deodorants, and shaving creams contained the lowest levels of titanium (<0.01 μg/mg). For several high-consumption pharmaceuticals, the titanium content ranged from below the instrument detection limit (0.0001 μg Ti/mg) to a high of 0.014 μg Ti/mg. Electron microscopy and stability testing of food-grade TiO2 (E171) suggests that approximately 36% of the particles are less than 100 nm in at least one dimension and that it readily disperses in water as fairly stable colloids. However, filtration of water solubilized consumer products and personal care products indicated that less than 5% of the titanium was able to pass through 0.45 or 0.7 μm pores. Two white paints contained 110 μg Ti/mg while three sealants (i.e., prime coat paint) contained less titanium (25 to 40 μg Ti/mg). This research showed that while many white-colored products contained titanium, it was not a prerequisite. Although several of these product classes contained low amounts of titanium, their widespread use and disposal down the drain and eventually to WWTPs deserves attention. A Monte Carlo human exposure analysis to TiO2 through foods identified children as having the highest exposures because TiO2 content of sweets is higher than other food products, and that a typical exposure for a US adult may be on the order of 1 mg Ti per kilogram body weight per day. Thus, because of the millions of tons of titanium based white pigment used annually, testing should focus on food-grade TiO2 (E171) rather than that adopted in many environmental health and safety tests (i.e., P25), which is used in much lower amounts in products less likely to enter the environment (e.g., catalyst supports, photocatalytic coatings).
Epilepsy or seizure disorder is one of the most common neurological diseases in humans. Although genetic mutations in ion channels and receptors and some other risk factors such as brain injury are linked to epileptogenesis, the underlying cause for the majority of epilepsy cases remains unknown. Gene-environment interactions are thought to play a critical role in the etiology of epilepsy. Exposure to environmental chemicals is an important risk factor. Methylmercury (MeHg) is a prominent environmental neurotoxicant, which targets primarily the central nervous system (CNS). Patients or animals with acute or chronic MeHg poisoning often display epileptic seizures or show increased susceptibility to seizures, suggesting that MeHg exposure may be associated with epileptogenesis. This mini-review highlights the effects of MeHg exposure, especially developmental exposure, on the susceptibility of humans and animals to seizures, and discusses the potential role of low level MeHg exposure in epileptogenesis. This review also proposes that a preferential effect of MeHg on the inhibitory GABAergic system, leading to disinhibition of excitatory glutamatergic function, may be one of the potential mechanisms underlying MeHg-induced changes in seizure susceptibility.
Seaweed and soy foods are consumed daily in Japan, where breast cancer rates for postmenopausal women are significantly lower than in the West. Likely mechanisms include differences in diet, especially soy consumption, and estrogen metabolism. Fifteen healthy postmenopausal women participated in this double-blind trial of seaweed supplementation with soy challenge. Participants were randomized to 7 wk of either 5 g/d seaweed (Alaria) or placebo (maltodextrin). During wk 7, participants also consumed a daily soy protein isolate (2 mg isoflavones/kg body weight). After a 3-wk washout period, participants were crossed over to the alternate supplement schedule. There was an inverse correlation between seaweed dose (mg/kg body weight) and serum estradiol (E2) (seaweed-placebo = y = -2.29 x dose + 172.3; r = -0.70; P = 0.003), [corrected] which was linear across the range of weights. Soy supplementation increased urinary daidzein, glycitein, genistein, and O-desmethylangolensin (P = 0.0001) and decreased matairesinol and enterolactone (P < 0.05). Soy and seaweed plus soy (SeaSoy) increased urinary excretion of 2-hydroxyestrogen (2-OHE) (P = 0.0001) and the ratio of 2-OHE:16alpha-hydroxyestrone (16alphaOHE(1)) (P = 0.01). For the 5 equol excretors, soy increased urinary equol excretion (P = 0.0001); the combination of SeaSoy further increased equol excretion by 58% (P = 0.0001). Equol producers also had a 315% increase in 2:16 ratio (P = 0.001) with SeaSoy. Seaweed favorably alters estrogen and phytoestrogen metabolism and these changes likely include modulation of colonic bacteria.
Saffron (Crocus sativus Linn.) have been perceived by the public as a strong aphrodisiac herbal product. However, studies addressing the potential beneficial effects of saffron on erectile function (EF) in men with ED are lacking. Our aim was to evaluate the efficacy and safety of saffron administration on EF in men with ED. After a 4-week baseline assessment, 346 men with ED (mean age 46.6+/-8.4 years) were randomized to receive on-demand sildenafil for 12 weeks followed by 30 mg saffron twice daily for another 12 weeks or vice versa, separated by a 2-week washout period. To determine the type of ED, penile color duplex Doppler ultrasonography before and after intracavernosal injection with 20 microg prostaglandin E(1), pudendal nerve conduction tests and impaired sensory-evoked potential studies were performed. Subjects were assessed with an International Index of Erectile Function (IIEF) questionnaire, Sexual Encounter Profile (SEP) diary questions, patient and partner versions of the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) questionnaire and the Global Efficacy Question (GEQ) 'Has the medication you have been taking improved your erections?' No significant improvements were observed with regard to the IIEF sexual function domains, SEP questions and EDITS scores with saffron administration. The mean changes from baseline values in IIEF-EF domain were +87.6% and +9.8% in sildenafil and placebo groups, respectively (P=0.08). We did not observe any improvement in 15 individual IIEF questions in patients while taking saffron. Treatment satisfaction as assessed by partner versions of EDITS was found to be very low in saffron patients (72.4 vs 25.4, P=0.001). Mean per patient 'yes' responses to GEQ was 91.2 and 4.2% for sildenafil and saffron, respectively (P=0.0001). These findings do not support a beneficial effect of saffron administration in men with ED.
We report a series of cases of thyroid dysfunction in adults associated with ingestion of a brand of soy milk manufactured with kombu (seaweed), and a case of hypothyroidism in a neonate whose mother had been drinking this milk. We also report two cases of neonatal hypothyroidism linked to maternal ingestion of seaweed made into soup. These products were found to contain high levels of iodine. Despite increasing awareness of iodine deficiency, the potential for iodine toxicity, particularly from sources such as seaweed, is less well recognised.
The importance of dietary sulforaphane in helping maintain good health continues to gain support within the health-care community and awareness among U.S. consumers. In addition to the traditional avenue for obtaining sulforaphane, namely, the consumption of appropriate cruciferous vegetables, other consumer products containing added glucoraphanin, the natural precursor to sulforaphane, are now appearing in the United States. Crucifer seeds are a likely source for obtaining glucoraphanin, owing to a higher concentration of glucoraphanin and the relative ease of processing seeds as compared to vegetative parts. Seeds of several commonly consumed crucifers were analyzed not only for glucoraphanin but also for components that might have negative health implications, such as certain indole-containing glucosinolates and erucic acid-containing lipids. Glucoraphanin, 4-hydroxyglucobrassicin, other glucosinolates, and lipid erucic acid were quantified in seeds of 33 commercially available cultivars of broccoli, 4 cultivars each of kohlrabi, radish, cauliflower, Brussels sprouts, kale, and cabbage, and 2 cultivars of raab.
The inhibitory effect of Old Coke, caffeine-free New Coke, New Coke, Diet Coke and Pepsi-Cola on human sperm motility was studied with a trans-membrane migration method. None of them could decrease sperm motility to less than 70% of control within one hour. A previous study which claimed a marked variation of spermicidal potencies among different formulations of Coca-Cola could not be confirmed. Even if cola has a spermicidal effect, its potency is relatively weak as compared with other well-known spermicidal agents.
Dry-eye syndrome (DES) is a multifactorial disease affecting millions of individuals worldwide. Various factors, including age, hormonal status, genetics, sex, immune status, innervation status, nutrition, pathogens, and environmental stress, can alter the cellular and molecular structure or function of components of the ocular surface system. The resulting imbalance increases susceptibility to desiccation and epithelial damage, leading to a vicious circle in which inflammation amplifies and sustains further damage by chronic deregulation of the system. Lubricating agents and steroids have been used as treatment options. However, as the causes of the disease become better elucidated, the more chemically complex cyclosporine A has become an increasingly useful treatment option and in the United States is currently the only Food and Drug Administration (FDA)-approved prescription drug for the treatment of dry eye. The safety and efficacy of cyclosporine have been shown in numerous studies.
Snacking is an uncontrolled eating behavior, predisposing weight gain and obesity. It primarily affects the female population and is frequently associated with stress. We hypothesized that oral supplementation with Satiereal (Inoreal Ltd, Plerin, France), a novel extract of saffron stigma, may reduce snacking and enhance satiety through its suggested mood-improving effect, and thus contribute to weight loss. Healthy, mildly overweight women (N = 60) participated in this randomized, placebo-controlled, double-blind study that evaluated the efficacy of Satiereal supplementation on body weight changes over an 8-week period. Snacking frequency, the main secondary variable, was assessed by daily self-recording of episodes by the subjects in a nutrition diary. Twice a day, enrolled subjects consumed 1 capsule of Satiereal (176.5 mg extract per day (n = 31) or a matching placebo (n = 29). Caloric intake was left unrestricted during the study. At baseline, both groups were homogeneous for age, body weight, and snacking frequency. Satiereal caused a significantly greater body weight reduction than placebo after 8 weeks (P < .01). The mean snacking frequency was significantly decreased in the Satiereal group as compared with the placebo group (P < .05). Other anthropometric dimensions and vital signs remained almost unchanged in both groups. No subject withdrawal attributable to a product effect was reported throughout the trial, suggesting a good tolerability to Satiereal. Our results indicate that Satiereal consumption produces a reduction of snacking and creates a satiating effect that could contribute to body weight loss. The combination of an adequate diet with Satiereal supplementation might help subjects engaged in a weight loss program in achieving their objective. Copyright 2010 Elsevier Inc. All rights reserved.
Brains from 32 neonatal autopsies from the Seychelles were examined histologically and analyzed for mercury levels. Six brain regions were sampled: frontal and occipital cortex, temporal cortex with hippocampus, basal ganglia with thalamus, cerebellum, and pons with medulla. Tissue blocks for histology and mercury analysis were taken from opposing faces to provide for correlation of findings. Similar studies were performed on 12 reference neonatal brains from Rochester, New York. No clear-cut developmental abnormality was found, but some brains exhibited low-grade, non-specific destructive changes. Total mercury levels, most of it in the organic form, were elevated in many of the Seychelles specimens. No correlation was demonstrated between mercury levels and degree or type of histologic change. There was considerable variability in total mercury for each anatomic region among the 32 Seychelles cases, as well as from one region to another in individual brains. All values of total mercury were under 300 ppb. Statistical analysis of mean mercury levels for each region demonstrated higher values in deep subcortical nuclei, brain stem, and cerebellum, phylogenetically older parts of the brain. When total mercury concentration of each region was paired with all other areas in the same brain and the paired values plotted for the entire group of brains, high correlations were obtained for all brain pairs, suggesting a strong concentration-dependent relationship between mercury intake and brain content. Analysis of mercury levels in separately dissected blocks of grey and white matter from 12 specimens revealed no significant differences between grey and white. In comparison with other human developmental studies and with experimental developmental studies in animals, where toxicity has been demonstrated with total mercury brain levels above 1,000 ppb, this study found no evidence of toxicity within a range of mercury levels below 300 ppb. Submicroscopic changes, subcellular alterations, subtle disturbances in the unfolding of brain architectonics -- none of these are excluded with methods used in this report. Further studies of threshold effects of MeHg on fetal brain are essential. That approximately half of the mercury resides in glial elements in white matter reinforces the need to focus attention upon glia as well as neurons during development.
The consequences of a change from a mixed to a lactovegetarian diet for 12 mo on trace element concentrations in plasma, hair, urine, and feces were studied in 16 women and 4 men. After the diet shift, intakes of zinc and magnesium did not change but that of selenium decreased by 40%. Three months after the diet shift, plasma and hair concentrations of zinc, copper, and selenium had decreased but those of magnesium had increased and the concentrations of mercury, lead, and cadmium in hair were lower. Also, the excretion of zinc, copper, and magnesium in urine, and that of selenium in urine and feces had decreased. Only small changes occurred during the remaining lactovegetarian-diet period. Three years later trace element concentrations had reverted towards baseline concentrations; copper values were similar to baseline concentrations but data for magnesium were slightly higher, and more complex patterns were observed for zinc and selenium. It is concluded that a shift to a lactovegetarian diet changes trace element status.
OBJECTIVES: To summarize and compare evidence on harms in sildenafil- and placebo-treated men with erectile dysfunction (ED) in a systematic review and meta-analysis. METHODS: Randomized placebo-controlled trials (RCTs) were identified using an electronic search in MEDLINE, EMBASE, PsycINFO, SCOPUS, and Cochrane CENTRAL. The rates of any adverse events (AEs), most commonly reported AEs, withdrawals because of adverse events, and serious adverse events were ascertained and compared between sildenafil and placebo groups. The results of men with ED were stratified by clinical condition(s). Statistical heterogeneity was explored. Meta-analyses based on random-effects model were also performed. RESULTS: A total of 49 RCTs were included. Sildenafil-treated men had a higher risk for all-cause AEs (RR = 1.56, 95% CI: 1.38, 1.76), headache, flushing, dyspepsia, and visual disturbances compared with placebo-treated men. The magnitude of excess risk was greater in fixed- than in flexible-dose trials. The rates of serious adverse events and withdrawals because of adverse events did not differ in sildenafil vs placebo groups. A higher dose of sildenafil corresponded to a greater risk of AEs. The increased risk of harms was observed within and across clinically defined specific groups of patients. CONCLUSIONS: There was a lack of RCTs reporting long-term (>6 months) harms data. In short-term trials, men with ED randomized to sildenafil had an increased risk of all-cause any AEs, headache, flushing, dyspepsia, and visual disturbances. The exploration of different modes of dose optimization of sildenafil may be warranted.
There is growing interest in the potential health benefits of tea, including the antimutagenic properties. Four varieties of white tea, which represent the least processed form of tea, were shown to have marked antimutagenic activity in the Salmonella assay, particularly in the presence of S9. The most active of these teas, Exotica China white tea, was significantly more effective than Premium green tea (Dragonwell special grade) against 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and four other heterocyclic amine mutagens, namely 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline (4,8-DiMeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2). Mechanism studies were performed using rat liver S9 in assays for methoxyresorufin O-demethylase (MROD), a marker for the enzyme cytochrome P4501A2 that activates heterocyclic amines, as well as Salmonella assays with the direct-acting mutagen 2-hydroxyamino-3-methylimidazo[4,5-f]quinoline (N-hydroxy-IQ). White tea at low concentrations in the assay inhibited MROD activity, and attenuated the mutagenic activity of N-hydroxy-IQ in the absence of S9. Nine of the major constituents found in green tea also were detected in white tea, including high levels of epigallocatechin-3-gallate (EGCG) and several other polyphenols. When these major constituents were mixed to produce "artificial" teas, according to their relative levels in white and green teas, the complete tea exhibited higher antimutagenic potency compared with the corresponding artificial tea. The results suggest that the greater inhibitory potency of white versus green tea in the Salmonella assay might be related to the relative levels of the nine major constituents, perhaps acting synergistically with other (minor) constituents, to inhibit mutagen activation as well as "scavenging" the reactive intermediate(s).
The behavior of inhibitors of monoamine oxidase-A (MAO-A) is considered in terms of the possibility of having an effective antidepressant that does not give rise to hypertensive interactions with dietary tyramine. Studies with punch-biopsy samples of human intestine and rat intestinal samples show MAO-A to be the predominant form of the enzyme in both species. Transport studies with everted rat intestinal preparations indicate that tyramine is extensively metabolized during transport through the intestine. Selective inhibition of MAO-A by clorgyline results in a large increase in the amount of unchanged tyramine transported, whereas selective inhibition of MAO-B with L-deprenyl (selegiline) has no significant effect. The behavior of reversible MAO-A inhibitors can significantly reduce, but not entirely eliminate, these effects on the intestinal metabolism of tyramine, but only if the inhibition is competitive in nature.