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2.
Nat Ecol Evol ; 3(12): 1645-1649, 2019 12.
Article in English | MEDLINE | ID: mdl-31712694

ABSTRACT

Steep insect biomass declines ('insectageddon') have been widely reported, despite a lack of continuously collected biomass data from replicated long-term monitoring sites. Such severe declines are not supported by the world's longest running insect population database: annual moth biomass estimates from British fixed monitoring sites revealed increasing biomass between 1967 and 1982, followed by gradual decline from 1982 to 2017, with a 2.2-fold net gain in mean biomass between the first (1967-1976) and last decades (2008-2017) of monitoring. High between-year variability and multi-year periodicity in biomass emphasize the need for long-term data to detect trends and identify their causes robustly.


Subject(s)
Moths , Animals , Biomass , United Kingdom
3.
Nat Commun ; 6: 7794, 2015 Jul 28.
Article in English | MEDLINE | ID: mdl-26215251

ABSTRACT

Establishing the phase diagram of hydrogen is a major challenge for experimental and theoretical physics. Experiment alone cannot establish the atomic structure of solid hydrogen at high pressure, because hydrogen scatters X-rays only weakly. Instead, our understanding of the atomic structure is largely based on density functional theory (DFT). By comparing Raman spectra for low-energy structures found in DFT searches with experimental spectra, candidate atomic structures have been identified for each experimentally observed phase. Unfortunately, DFT predicts a metallic structure to be energetically favoured at a broad range of pressures up to 400 GPa, where it is known experimentally that hydrogen is non-metallic. Here we show that more advanced theoretical methods (diffusion quantum Monte Carlo calculations) find the metallic structure to be uncompetitive, and predict a phase diagram in reasonable agreement with experiment. This greatly strengthens the claim that the candidate atomic structures accurately model the experimentally observed phases.

4.
J Appl Toxicol ; 34(3): 241-9, 2014 Mar.
Article in English | MEDLINE | ID: mdl-23508487

ABSTRACT

Aflatoxin B1 (AFB1) is immunotoxic to animals and a suspected immunosuppressant in humans. In this study, we investigated the effects of AFB1 on splenic lymphocyte phenotypes and the inflammatory cytokine expression in male F344 rats. Exposure of animals to AFB1 [5-75 µg kg(-1) body weight (BW)] for 1 week showed dose-dependent decreases in the percentage of splenic CD8(+) T cells and CD3(-) CD8a(+) NK cells. A general inhibition of the expression of interleukin (IL)-4 and interferon (IFN)-γ by CD4(+) T cells, IL-4 and IFN-γ by CD8a(+) cells, and tumor necrosis factor (TNF)-α expression by natural killer (NK) cells was also found; however, no concurrent histological changes in spleen tissue were present, suggesting acute immunosuppression without overt toxicity. Five-week exposure with AFB1 significantly increased the percentages of CD3(+) and CD8(+) T cells, especially at low doses (≤ 25 µg kg(-1)). AFB1 treatment significantly decreased the anti-inflammatory cytokine IL-4 expression by CD4(+) T cells and significantly increased the pro-inflammatory cytokine IFN-γ expression by CD4(+) T cells and TNF-α expression by NK cells. These results indicated that repeated AFB1 exposure promotes inflammatory responses by regulating cytokine expression. Our data provides novel insights into the mechanisms by which AFB1 exposure differentially modulates the cell-mediated immune responses and suggests the involvement of an inflammatory response upon repeated exposure.


Subject(s)
Aflatoxin B1/toxicity , Cytokines/biosynthesis , Environmental Pollutants/toxicity , Lymphocytes/drug effects , Spleen/drug effects , Administration, Oral , Animals , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , Dose-Response Relationship, Drug , Flow Cytometry , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Lymphocytes/immunology , Male , Phenotype , Rats , Rats, Inbred F344 , Spleen/immunology , T-Lymphocyte Subsets/drug effects , T-Lymphocyte Subsets/immunology
5.
Toxicol Pathol ; 41(8): 1093-105, 2013.
Article in English | MEDLINE | ID: mdl-23423819

ABSTRACT

In this study, male F344 rats were orally exposed to a single dose of aflatoxin B1 (AFB1) at 0, 50, 250, or 1,000 µg/kg body weight (BW) or repeated dose of 0, 5, 10, 25, or 75 µg/kg BW for up to 5 weeks. Biochemical and histological changes were assessed together with the formation of AFB1-lysine adduct (AFB-Lys) and liver foci positive for placental form glutathione S transferase (GST-P⁺). In single-dose protocol, serum aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP) showed dose-related elevation, with maximal changes observed (>100-fold) at day 3 after treatment. Animals that received 250 µg/kg AFB1 showed concurrent bile duct proliferation, necrosis, and GST-P⁺ hepatocytes at 3 day, followed by liver GST-P⁺ foci appearance at 1 week. In repeated-dose protocol, bile duct proliferation and liver GST-P⁺ foci co-occurred after 3-week exposure to 75 µg/kg AFB1, followed by proliferation foci formation after 4 week and dramatic ALT, AST, and CK elevations after 5 weeks. Liver GST-P⁺ foci were induced temporally and in a dose-related manner. Serum AFB-Lys increased temporally at low doses (5-25 µg/kg), and reached the maximum after 2-week exposure at 75 µg/kg. This integrative study demonstrated that liver GST-P⁺ cells and foci are sensitive biomarkers for AFB1 toxic effect and correlated with bile duct proliferation and biochemical alterations in F344 rats.


Subject(s)
Aflatoxin B1/toxicity , Toxicity Tests/methods , Aflatoxin B1/blood , Aflatoxin B1/metabolism , Analysis of Variance , Animals , Bile Ducts/chemistry , Bile Ducts/drug effects , Bile Ducts/pathology , Blood Chemical Analysis , Body Weight/drug effects , Glutathione Transferase/metabolism , Histocytochemistry , Liver/chemistry , Liver/drug effects , Liver/metabolism , Liver/pathology , Lysine/blood , Lysine/metabolism , Male , Random Allocation , Rats , Rats, Inbred F344
6.
Toxicology ; 303: 147-51, 2013 Jan 07.
Article in English | MEDLINE | ID: mdl-23146766

ABSTRACT

Aflatoxin B(1)-lysine adduct (AFB-Lys) is a reliable biomarker for aflatoxin exposure; however, a systematic toxicokinetic evaluation has not been reported. In this study, male F344 rats were orally exposed to single, or repeated, doses of AFB(1) and the toxicokinetics of serum AFB-Lys that followed treatments were investigated. A single-dose of AFB(1) increased serum AFB-Lys levels rapidly peaking at 4h, followed by first-order elimination, through which the half-life was estimated to be 2.31 days. A physiologically based pharmacokinetic model showed that approximately 3.00-3.90% and 1.12-1.98% of the administered AFB(1) doses were converted to serum AFB-Lys adducts at 2h and 24h post treatment, respectively. Repeated AFB(1) exposure at 5-25 µg/kg body weight linearly increased serum AFB-Lys levels for 5 weeks in animals, resulting in a 1-1.5 times higher AFB-Lys level overall. This indicates the potential of this adduct as a reliable biomarker for repeated low dose exposure. Higher dose exposure at 75 µg/kg increased the level of AFB-Lys to a maximum at 2 weeks, followed by a gradual decrease to near plateau level up to 5 weeks. In conclusion, this study systematically evaluated the toxicokinetics of serum AFB-Lys adduct in F344 rats using a physiologically based pharmacokinetic model and robust statistical modeling analysis and provided a firm and clear understanding of the toxicokinetics of this biomarker.


Subject(s)
Aflatoxin B1/toxicity , Lysine/blood , Models, Biological , Models, Statistical , Aflatoxin B1/administration & dosage , Aflatoxin B1/blood , Animals , Biomarkers/blood , Dose-Response Relationship, Drug , Half-Life , Male , Rats , Rats, Inbred F344 , Time Factors
7.
J Food Sci ; 77(12): M659-63, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23106385

ABSTRACT

Mortality resulting from diarrhea especially that occurs in children younger than 5 y of age ranks 3rd among all deaths caused by infectious diseases worldwide. Probiotics such as Lactobacillus rhamnosus GG are clinically shown to effectively reduce the incidence of diarrhea in children. A food substrate is one of the major factors regulating the colonization of microorganisms in human gastrointestinal tracts. Peanut butter is a nutritious, low-moisture food that could be a carrier for probiotics. In this study, we observed the influence of storage conditions and product matrixes on the survival of L. rhamnosus GG. Cells of L. rhamnosus GG were inoculated into full fat or reduced fat peanut butter at 10(7) CFU/g. Inoculated peanut butter was stored at 4, 25, or 37 °C for 48 wk. Samples were drawn periodically to determine the populations of L. rhamnosus GG. Results showed that there was no significant decrease in the viable counts of L. rhamnosus GG in products stored 4 °C. The survivability of L. rhamnosus GG decreased with increasing storage temperature and time. Product matrixes did not significantly affect the survival of L. rhamnosus GG except at 37 °C. Populations of L. rhamnosus GG were preserved at >6 logs in products stored at 4 °C for 48 wk and at 25 °C for 23 to 27 wk. At 37 °C, the 6-log level could not be maintained for even 6 wk. The results suggest that peanut butter stored at 4 and 25 °C could serve as vehicles to deliver probiotics.


Subject(s)
Arachis/microbiology , Food Microbiology , Food Storage/methods , Lacticaseibacillus rhamnosus/growth & development , Probiotics , Arachis/chemistry , Diarrhea/therapy , Fats/analysis , Food Handling , Gastrointestinal Tract/microbiology , Humans , Hydrogen-Ion Concentration , Incidence , Malnutrition/therapy , Temperature
8.
Alzheimers Res Ther ; 3(1): 5, 2011 Feb 17.
Article in English | MEDLINE | ID: mdl-21329517

ABSTRACT

INTRODUCTION: Levels of cerebrospinal fluid (CSF) ß-amyloid (Aß) and Tau proteins change in Alzheimer's disease (AD). We tested if the relationships of these biomarkers with cognitive impairment are linear or non-linear. METHODS: We assessed cognitive function and assayed CSF Aß and Tau biomarkers in 95 non-demented volunteers and 97 AD patients. We then tested non-linearities in their inter-relations. RESULTS: CSF biomarkers related to cognitive function in the non-demented range of cognition, but these relations were weak or absent in the patient range; Aß1-40's relationship was biphasic. CONCLUSIONS: Major biomarker changes precede clinical AD and index cognitive impairment in AD poorly, if at all.

9.
Article in English | MEDLINE | ID: mdl-34603628

ABSTRACT

BACKGROUND: Aflatoxin exposure has been shown to cause cell-mediated immune suppression and enhance HIV viral replication. Such immune suppression from aflatoxin can impair resistance to both infectious diseases and chronic infections. METHODS: Hazard ratios (HRs) with 95% confidence intervals (CI) and a test for trend for opportunistic infections OI) among 141 HIV positive Ghanaians based on quartiles of aflatoxin B1 albumin adduct levels (AF-ALB) were calculated. FINDINGS: HRs were significantly higher for developing symptomatic TB (HR 3.30, 95% CI 1.34-8.11) for those in the highest AF-ALB quartile compared to the lowest. Significantly higher HRs were not observed for other infections investigated. CONCLUSIONS: Those with the highest levels AF-ALB from dietary intake have an increased hazard of symptomatic TB but not malaria, HBV, or pneumonia.

10.
Neurochem Int ; 57(8): 985-9, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21034788

ABSTRACT

The cannabinoid CB1 receptor has gained much attention as a potential pharmacotherapeutic target in various neurodegenerative diseases including Alzheimer's disease (AD). However, the relation of CB1 receptors to cognitive function in AD is at present unclear. In this study, postmortem brain tissues from a cohort of prospectively assessed, neuropathologically confirmed AD patients and aged controls were used to measure CB1 receptors by immunoblotting, and a subset of subjects also had [(3)H]SR141716A binding. Correlational analyses were then performed for the neurochemical and cognitive data. We found that CB1 receptor levels in were unchanged AD in the brain regions assessed (frontal cortex, anterior cingulate gyrus, hippocampus, caudate nucleus). Within the AD group, frontal cortical CB1 immunoreactivity correlated with cognitive scores assessed within a year of death. Our study suggests that CB1 receptors are intact in AD and may play a role in preserving cognitive function. Therefore, CB1 receptors should be further assessed as a potential therapeutic target in AD.


Subject(s)
Alzheimer Disease/metabolism , Cerebral Cortex/metabolism , Receptor, Cannabinoid, CB1/metabolism , Aged , Aged, 80 and over , Alzheimer Disease/drug therapy , Alzheimer Disease/psychology , Cerebral Cortex/pathology , Cognition/physiology , Cohort Studies , Female , Humans , Male , Middle Aged , Prospective Studies
11.
Am J Trop Med Hyg ; 83(5): 1077-83, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21036841

ABSTRACT

Aflatoxins are fungal metabolites that contaminate staple food crops in many developing countries. Up to 40% of women attending a prenatal clinic in Africa may be anemic. In a cross-sectional study of 755 pregnant women, Aflatoxin B(1)-lysine adducts (AF-ALB) levels were determined by high-performance liquid chromatography. Participants were divided into quartiles "low," "moderate," "high," and "very high." Anemia was defined as hemoglobin levels < 11 g/dL. Logistic regression was used to examine the association of anemia with AF-ALB. The mean AF-ALB level was 10.9 pg/mg (range = 0.44-268.73 pg/mg); 30.3% of participants were anemic. The odds of being anemic increased 21% (odds ratio [OR], 1.21, P = 0.01) with each quartile of AF-ALB reaching an 85% increased odds in the "very high" compared with the "low" category (OR, 1.85; confidence interval [CI], 1.16-2.95). This association was stronger among women with malaria and findings were robust when women with evidence of iron deficiency anemia were excluded. This study found a strong, consistent association between anemia in pregnancy and aflatoxins.


Subject(s)
Aflatoxin B1/toxicity , Anemia/chemically induced , Pregnancy Complications, Hematologic/chemically induced , Adult , Aflatoxin B1/blood , Aflatoxin B1/metabolism , Anemia/blood , Biomarkers/blood , Cross-Sectional Studies , Female , Food Contamination , Ghana/epidemiology , Humans , Logistic Models , Odds Ratio , Pregnancy , Pregnancy Complications, Hematologic/epidemiology , Risk Factors , Young Adult
12.
Sci Total Environ ; 408(23): 6027-31, 2010 Nov 01.
Article in English | MEDLINE | ID: mdl-20870273

ABSTRACT

The incidence of hepatocellular carcinoma (HCC) is significantly elevated in a Hispanic community in Bexar County, Texas. Chronic exposure to dietary aflatoxins (AFs) is a major risk factor for HCC; increased risk has been linked to polycyclic aromatic hydrocarbon (PAH) co-exposure and hepatitis virus infection. The aims of this study were to assess AF and PAH exposures, investigate dietary factors that may contribute to increased AF exposure, and determine the prevalence of hepatitis virus infection in Bexar Co. Blood and urine samples were collected from 184 volunteers for biomarker analyses and hepatitis screening. Serum AFB(1)-lysine adduct, urinary AFM(1) and 1-hydroxypyrene (1-OHP) levels were measured using high-performance liquid chromatography. The average AFB(1)-lysine adduct level detected in 20.6% of serums was 3.84 ± 3.11 pg/mg albumin (range 1.01-16.57 pg/mg). AFM(1) was detected in 11.7% of urines, averaging 223.85 ± 250.56 pg/mg creatinine (range 1.89-935.49 pg/mg). AFM(1) detection was associated with increased consumption of corn tortillas (p=0.009), nuts (p=0.033) and rice (p=0.037). A significant difference was observed between mean 1-OHP values of non-smokers (0.07 ± 0.13) and smokers (0.80 ± 0.68) µmol/mol creatinine (p<0.01). A high hepatitis C virus positivity rate (7.1%) was observed. Findings suggest that the incidence and level of AF and PAH exposure were less than those observed in a high-risk population; however, participants consuming higher amounts of foods prone to AF contamination may be more vulnerable to exposure and interactions with other environmental/biological factors (i.e., HCV).


Subject(s)
Aflatoxins/toxicity , Carcinoma, Hepatocellular/epidemiology , Environmental Pollutants/toxicity , Liver Neoplasms/epidemiology , Polycyclic Aromatic Hydrocarbons/toxicity , Adolescent , Adult , Aflatoxin B1/blood , Aflatoxin B1/urine , Aflatoxins/metabolism , Aged , Biomarkers/blood , Biomarkers/metabolism , Biomarkers/urine , Carcinoma, Hepatocellular/metabolism , Creatinine/metabolism , Diet , Environmental Exposure/analysis , Environmental Pollutants/metabolism , Female , Hepatitis, Viral, Human/epidemiology , Humans , Liver Neoplasms/metabolism , Lysine/blood , Lysine/urine , Male , Middle Aged , Polycyclic Aromatic Hydrocarbons/metabolism , Pyrenes/metabolism , Texas/epidemiology , Young Adult
13.
Am J Clin Nutr ; 92(1): 154-60, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20484447

ABSTRACT

BACKGROUND: Promotion of the HIV epidemic by aflatoxin is postulated but not yet established. Sub-Saharan populations commonly consume food contaminated by mycotoxins, particularly aflatoxins (predominantly found in peanut, maize, rice, and cassava) and fumonisins, which occur primarily in maize. Aflatoxin promotes hepatocellular cancer, and fumonisin may promote esophageal cancer. OBJECTIVES: This analysis was undertaken to test the hypotheses that consumption of mycotoxin-prone staple foods is 1) related to the incidence of HIV infection in Africa and 2) related to "signature" cancer rates confirming exposure to aflatoxins and fumonisins. DESIGN: World Health Organization data for causes of death and the Food and Agriculture Organization per capita consumption data for commodities in sub-Saharan Africa were used. Per capita Gross Domestic Product and the percentage of Muslims (%Muslim) were the socioeconomic data sets exploited. Relations between causes of mortality, consumption of mycotoxin-prone foods, and socioeconomic variables were evaluated. Models for HIV transmission as a function of maize consumption and %Muslim were estimated. RESULTS: HIV and esophageal cancer deaths were significantly related to maize but were inversely related to %Muslim and rice consumption. HIV infections were minimized (74 compared with 435/100,000 people; odds ratio: 2.41; 95% CI: 1.73, 3.24; P < or = 0.0001) by the combination of low maize consumption and above-median % Muslim. Hepatocellular cancer deaths were positively related to rice but negatively related to maize consumption. CONCLUSIONS: HIV transmission frequency is positively associated with maize consumption in Africa. The relation between cancer and food suggests that fumonisin contamination rather than aflatoxin is the most likely factor in maize promoting HIV. Changes to the quality of maize may avoid up to 1,000,000 transmissions of HIV annually.


Subject(s)
Carcinoma, Hepatocellular/epidemiology , Esophageal Neoplasms/epidemiology , Foodborne Diseases/complications , HIV Infections/epidemiology , Liver Neoplasms/epidemiology , Mycotoxins/toxicity , Africa South of the Sahara/epidemiology , Black People , Carcinoma, Hepatocellular/chemically induced , Carcinoma, Hepatocellular/mortality , Cause of Death , Environment , Esophageal Neoplasms/chemically induced , Esophageal Neoplasms/mortality , Feeding Behavior , Fumonisins/toxicity , HIV Infections/chemically induced , HIV Infections/mortality , HIV Infections/transmission , Humans , Liver Neoplasms/chemically induced , Liver Neoplasms/mortality , Mortality , Oryza/toxicity , Regression Analysis , Zea mays/toxicity
14.
Infect Dis Obstet Gynecol ; 2010: 350763, 2010.
Article in English | MEDLINE | ID: mdl-20379355

ABSTRACT

OBJECTIVE: The objective of the study was to assess Plasmodium/intestinal helminth infection in pregnancy and other risk factors for stillbirth in Ghana. METHODS: A cross-sectional study of women presenting for delivery in two hospitals was conducted during November-December 2006. Data collected included sociodemographic information, medical and obstetric histories, and anthropometric measures. Laboratory investigations for the presence of Plasmodium falciparum and intestinal helminths, and tests for hemoglobin levels were also performed. RESULTS: The stillbirth rate was relatively high in this population (5%). Most of the stillbirths were fresh and 24% were macerated. When compared to women with no malaria, women with malaria had increased risk of stillbirth (OR = 1.9, 95% CI = 1.2-9.3). Other factors associated with stillbirth were severe anemia, low serum folate concentration, past induced abortion, and history of stillbirth. CONCLUSION: The fact that most of the stillbirths were fresh suggests that higher quality intrapartum care could reduce stillbirth rates.


Subject(s)
Helminthiasis/epidemiology , Intestinal Diseases, Parasitic/epidemiology , Malaria/epidemiology , Pregnancy Complications, Parasitic/epidemiology , Stillbirth/epidemiology , Adolescent , Adult , Cross-Sectional Studies , Female , Ghana/epidemiology , Humans , Logistic Models , Middle Aged , Pregnancy , Risk Factors
15.
Reprod Toxicol ; 29(3): 262-70, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20045048

ABSTRACT

CONTEXT: Although it is known that aflatoxins have many adverse health effects, there is no systematic summary of how it affects the reproductive system or its reproductive health effects. OBJECTIVE: Summarize evidence on the reproductive health effects of aflatoxins. RESULTS: The search yielded 121 potential studies, of which 25 were retained. One study found a higher concentration of aflatoxins in the semen of infertile men (40% of cases compared to 8% of controls). Six studies found significant associations or correlations between low birth weight and aflatoxins while one study did not find any correlation. One study found maternal serum aflatoxin to be a risk factor for jaundice in infants (OR, 2.68; CI, 1.18-6.10). Overall, maternal breast milk in developing countries had higher rates of aflatoxin contamination than in high income countries. CONCLUSIONS: Stakeholders in developing countries need to take steps to reduce exposure of vulnerable populations to the toxic effects of aflatoxins.


Subject(s)
Aflatoxins/toxicity , Reproductive Medicine , Developing Countries , Female , Humans , Infant , Infant, Low Birth Weight , Infant, Newborn , Male , Milk, Human , Pregnancy , Risk Factors
16.
Am J Trop Med Hyg ; 82(1): 28-34, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20064991

ABSTRACT

This study was conducted to investigate the effect of Plasmodium falciparum and intestinal helminth coinfection on maternal anemia and birth outcomes. A cross-sectional study of 746 women who delivered in two hospitals in Kumasi was conducted. Data were collected using an investigator-administered questionnaire and from patients' medical records. Blood was collected for determination of P. falciparum and hemoglobin levels. Adverse pregnancy outcomes were high (44.6%). Coinfection (versus no infection) was associated with 3-fold increase in low birth weight. For women with anemia, coinfection was 2.6 times and 3.5 times as likely to result in preterm deliveries and small for gestational age infants. The odds of having anemia was increased almost 3-fold by coinfection. Coinfection (versus helminth only) resulted in increased risks of anemia, low birth weight, and small for gestational age infants. This study demonstrates that women with malaria and intestinal helminth coinfection are at particular risk of adverse birth outcomes.


Subject(s)
Helminthiasis/complications , Intestinal Diseases, Parasitic/complications , Malaria, Falciparum/complications , Pregnancy Complications, Parasitic/physiopathology , Pregnancy Outcome , Adolescent , Adult , Female , Ghana/epidemiology , Helminthiasis/physiopathology , Humans , Intestinal Diseases, Parasitic/physiopathology , Malaria, Falciparum/physiopathology , Middle Aged , Pregnancy
17.
Trop Med Int Health ; 15(2): 160-7, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20003033

ABSTRACT

OBJECTIVE: To investigate the association between birth outcomes and blood levels of aflatoxin B(1) (AFB1)-lysine adduct in pregnant women in Kumasi, Ghana. METHOD: A cross-sectional study of 785 pregnant women attending antenatal clinic was conducted. Aflatoxin B(1) (AFB(1))-lysine adduct levels were determined by high performance liquid chromatography (HPLC) on blood taken after delivery. The birth outcomes considered were small for gestation age, low birthweight, preterm delivery and stillbirth. Participants were divided into quartiles based on the distribution of aflatoxin B(1)-lysine adducts in pg/mg albumin ('low': 2.67 to 4.97 to 11.34). Statistical analysis involved models that included socio-demographic variables and other potential confounders. RESULTS: The average AFB(1)-lysine adduct level in maternal serum was 10.9 +/- 19.00 pg/mg albumin (range = 0.44-268.73 pg/mg). After adjusting for socio-demographic variables and potential confounding factors, participants in the highest AFB(1)-lysine quartile with 'very high' AFB(1)-lysine level (>11.34 pg/mg) were more likely to have low birthweight babies (OR, 2.09; 95% CI, 1.19-3.68), and showed a trend of increasing risk for low birthweight (P(trend) = 0.007) compared to participants in the lowest quartile. CONCLUSION: This study adds to the growing body of evidence that aflatoxins may increase the risk of adverse birth outcomes. The findings have implications for targeted nutritional education of pregnant women in areas with high levels of aflatoxin contamination of foods.


Subject(s)
Aflatoxin B1/blood , Poisons/blood , Pregnancy Outcome , Pregnancy/blood , Adult , Biomarkers/blood , Cross-Sectional Studies , Female , Humans , Infant, Low Birth Weight , Infant, Newborn , Infant, Premature , Infant, Small for Gestational Age , Socioeconomic Factors , Stillbirth , Young Adult
18.
Am J Trop Med Hyg ; 80(6): 896-901, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19478245

ABSTRACT

Both malaria and intestinal helminths are endemic in sub-Saharan Africa, and their co-infection occurs commonly. This cross-sectional study assessed the prevalence of malaria and intestinal helminth co-infection in a sample of > 700 pregnant women in Ghana and identified risk factors for co-infection. The prevalence of malaria infection, intestinal helminth infection(s), and co-infection was 36.3%, 25.7%, and 16.6%, respectively. Women with intestinal helminth infection(s) were 4.8 times more likely to have malaria infection. Young age, low income, being single, and being primigravid were each associated with increased odds of co-infection. These associations were present when assessed separately for primi- and multigravid women, but the strength of associations varied considerably for the two groups of women. Young age had the strongest association among both primigravid (odds ratio = 5.2) and multigravid (odds ratio = 3.2) women. This study shows relatively high prevalence rates of malaria, intestinal helminths, and co-infection in pregnant women in Ghana.


Subject(s)
Helminthiasis/complications , Intestinal Diseases, Parasitic/complications , Malaria/complications , Pregnancy Complications, Parasitic/epidemiology , Adolescent , Adult , Anthelmintics/administration & dosage , Anthelmintics/therapeutic use , Antimalarials/administration & dosage , Antimalarials/therapeutic use , Cross-Sectional Studies , Drug Combinations , Female , Ghana/epidemiology , Helminthiasis/epidemiology , Humans , Hygiene , Intestinal Diseases, Parasitic/epidemiology , Malaria/drug therapy , Malaria/epidemiology , Middle Aged , Pregnancy , Prevalence , Pyrimethamine/administration & dosage , Pyrimethamine/therapeutic use , Risk Factors , Socioeconomic Factors , Sulfadoxine/administration & dosage , Sulfadoxine/therapeutic use , Young Adult
19.
Sci Total Environ ; 407(6): 1886-91, 2009 Mar 01.
Article in English | MEDLINE | ID: mdl-19144392

ABSTRACT

It was postulated that a population in sub-Saharan Africa, known to be at high risk for aflatoxicosis due to frequent ingestion of aflatoxin (AF)-contaminated foods could also be exposed to polycyclic aromatic hydrocarbons (PAHs) from a variety of environmental sources. Previously, participants in this population were shown to be highly exposed to AFs, and this exposure was significantly reduced by intervention with NovaSil clay (NS). Objectives of this study were 1) to assess PAH exposure in participants from the AF study using urinary biomarker 1-hydroxypyrene (1-OHP); 2) examine the effect of NS clay and placebo (cellulose) treatment on 1-OHP levels; and 3) determine potential association(s) between AF and PAH exposures. A clinical trial was conducted in 177 Ghanaians who received either NS capsules as high dose or low dose, or placebo (cellulose) for a period of 3 months. At the start and end of the study, urine samples were analyzed for 1-OHP. Of the 279 total samples, 98.9% had detectable levels of 1-OHP. Median 1-OHP excretion in nonsmokers was 0.64 micromol/mol creatinine at baseline and 0.69 micromol/mol creatinine after 3 months. Samples collected at both time points did not show significant differences between placebo and NS-treated groups. There was no linear correlation between 1-OHP and AF-albumin adduct levels. Results show that this population is highly exposed to PAHs (and AFs), that NS and cellulose treatment had no statistically significant effect on 1-OHP levels, and that this urinary biomarker was not linearly related with AF exposure.


Subject(s)
Environmental Exposure/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Pyrenes/analysis , Adolescent , Adult , Aflatoxins/metabolism , Aflatoxins/poisoning , Antidotes/therapeutic use , Bentonite/therapeutic use , Double-Blind Method , Environmental Exposure/adverse effects , Female , Ghana , Humans , Male , Middle Aged , Poisoning/drug therapy , Poisoning/prevention & control , Poisoning/urine , Polycyclic Aromatic Hydrocarbons/metabolism , Polycyclic Aromatic Hydrocarbons/poisoning , Statistics, Nonparametric , Young Adult
20.
Clin Dev Immunol ; 2008: 790309, 2008.
Article in English | MEDLINE | ID: mdl-18695741

ABSTRACT

Both aflatoxin and the human immunodeficiency virus (HIV) cause immune suppression and millions of HIV-infected people in developing countries are chronically exposed to aflatoxin in their diets. We investigated the possible interaction of aflatoxin and HIV on immune suppression by comparing immune parameters in 116 HIV positive and 80 aged-matched HIV negative Ghanaians with high (> or =0.91 pmol/mg albumin) and low (<0.91 pmol/mg albumin) aflatoxin B1 albumin adduct (AF-ALB) levels. AF-ALB levels and HIV viral load were measured in plasma and the percentages of leukocyte immunophenotypes and cytokine expression were determined using flow cytometry. The cross-sectional comparisons found that (1) among both HIV positive and negative participants, high AF-ALB was associated with lower perforin expression on CD8+ T-cells (P = .012); (2) HIV positive participants with high AF-ALB had significantly lower percentages of CD4+ T regulatory cells (Tregs; P = .009) and naive CD4+ T cells (P = .029) compared to HIV positive participants with low AF-ALB; and (3) HIV positive participants with high AF-ALB had a significantly reduced percentage of B-cells (P = .03) compared to those with low AF-ALB. High AF-ALB appeared to accentuate some HIV associated changes in T-cell phenotypes and in B-cells in HIV positive participants.


Subject(s)
Aflatoxins/toxicity , CD4-Positive T-Lymphocytes/drug effects , HIV Infections/immunology , Immune System Diseases/chemically induced , Lymphocyte Subsets/drug effects , Aflatoxins/blood , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , HIV/immunology , HIV Infections/blood , HIV Infections/complications , HIV Seropositivity , Humans , Immune System Diseases/complications , Lymphocyte Subsets/immunology , Perforin/metabolism
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