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Y Y Gong

Publications and source records attributed to Y Y Gong.

10 recordsLinked to original sources
PubMed2005

Dietary exposure to aflatoxin from maize and groundnut in young children from Benin and Togo, West Africa.

Aflatoxins are a family of fungal toxins that are carcinogenic to man and cause immunosuppression, cancer and growth reduction in animals. We conducted a cross-sectional study among 480 children (age 9 months to 5 years) across 4 agro-ecological zones (SS, NGS, SGS and CS) in Benin and Togo to identify the effect of aflatoxin exposure on child growth and assess the pattern of exposure. Prior reports on this study [Gong, Y.Y.,Cardwell, K., Hounsa, A., Egal, S., Turner, Hall, A.J., Wild, C.P., 2002. Dietary aflatoxin exposure and impaired growth in young children from Benin and Togo: cross sectional study. British Medical Journal 325, 20-21, Gong, Y.Y., Egal, S., Hounsa, A., Turner, P.C., Hall, A.J., Cardwell, K., Wild, C.P., 2003. Determinants of aflatoxin exposure in young children from Benin and Togo, West Africa: the critical role of weaning and weaning foods. International Journal of Epidemiology, 32, 556-562] showed that aflatoxin exposure among these children is widespread (99%) and that growth faltering is associated with high blood aflatoxin-albumin adducts (AF-alb adducts), a measure of recent past exposure. The present report demonstrates that consumption of maize is an important source of aflatoxin exposure for the survey population. Higher AF-alb adducts were correlated with higher A. flavus (CFU) infestation of maize (p=0.006), higher aflatoxin contamination (ppb) of maize (p<0.0001) and higher consumption frequencies of maize (p=0.053). The likelihood of aflatoxin exposure from maize was particularly high in agro-ecological zones where the frequency of maize consumption (SGS and CS), the presence of aflatoxin in maize (SGS) or the presence of A. flavus on maize (NGS and SGS) was relatively high. Socio-economic background did not affect the presence of A. flavus and aflatoxin in maize, but better maternal education was associated with lower frequencies of maize consumption among children from the northernmost agro-ecological zone (SS) (p=0.001). The impact of groundnut consumption on aflatoxin exposure was limited in this population. High AF-alb adduct levels were correlated with high prevalence of A. flavus and aflatoxin in groundnut, but significance was weak after adjustment for weaning status, agro-ecological zone and maternal socio-economic status (resp. p=0.091 and p=0.083). Ingestion of A. flavus and aflatoxin was high in certain agro-ecological zones (SS and SGS) and among the higher socio-economic strata due to higher frequencies of groundnut consumption. Contamination of groundnuts was similar across socio-economic and agro-ecological boundaries. In conclusion, dietary exposure to aflatoxin from groundnut was less than from maize in young children from Benin and Togo. Intervention strategies that aim to reduce dietary exposure in this population need to focus on maize consumption in particular, but they should not ignore consumption of groundnuts.

Aflatoxins↗
PubMed2005

Relationships of C-reactive protein, uric acid, and glomerular filtration rate to arterial stiffness in Japanese subjects.

The relationships between C-reactive protein (CRP), uric acid (UA), glomerular filtration rate (GFR), and arterial stiffness have not been fully investigated. The aim of this study was to clarify whether CRP, UA, and estimated GFR are related to arterial stiffness estimated using brachial-ankle pulse wave velocity (baPWV). The subjects were local government employees (3412 men and 854 women). baPWV, CRP, UA, GFR, and conventional risk factors were evaluated. Multiple linear regression analyses revealed that CRP and UA were significantly related to an elevation of PWV in male and female subjects, and that the estimated GFR was significantly related to an elevation of PWV in male subjects. Significant progressive increases in baPWV were observed across the quartiles of CRP in male subjects and for UA in male and female subjects. In female subjects, the relationship of quartile CRP to baPWV had marginal significance (P = 0.055). But, in male and female subjects, quartile of estimated GFR had no significant association with PWV. These results suggest that CRP and UA are associated with an increase of arterial stiffness in male and female subjects, and that estimated GFR is possibly related to arterial stiffness in male subjects.

Adult↗
PubMed2004

Symptoms in relation to chemicals and dampness in newly built dwellings.

OBJECTIVES: As the airtightness of dwellings has recently increased, problems associated with indoor air pollution and dampness have become important environmental health issues. The aim of this study was to clarify whether symptoms in residents living in newly built dwellings were related to chemicals and dampness. METHODS: Symptoms of 317 residents were surveyed by standardized questionnaires, and the concentrations of formaldehyde, acetaldehyde, and 17 volatile organic compounds (VOCs) in their homes were measured. Dampness (condensation on window panes and/or walls, and mold growth) was identified by questionnaires given to the householders or their partners. RESULTS: Some VOCs (toluene, butyl acetate, ethylbenzene, alpha-pinene, p-dichlorobenzene, nonanal, and xylene) were significantly related to the symptoms, and the sum of all VOCs (all identified VOCs) was significantly related to throat and respiratory symptoms [odds ratio (OR) for eye symptoms =2.4; 95% confidence interval (CI) 1.0-5.5], although the concentrations of VOCs were relatively low. As for the dampness index, condensation on window panes and/or walls was related to all symptoms, and mold growth was related to all symptoms except skin, throat and respiratory and general symptoms. As the number of dampness signs increased, the ORs increased for the symptoms except general symptoms (OR for nose symptoms = 4.4, 95% CI 1.6-11.9). CONCLUSION: Both VOCs and dampness were significantly related to symptoms. We should take measures to reduce the concentrations of VOCs, dampness and microbial growth in dwellings.

Acetaldehyde↗
PubMed2004

Ah receptor, CYP1A1, CYP1A2 and CYP1B1 gene polymorphisms are not involved in the risk of recurrent pregnancy loss.

The etiology of recurrent pregnancy loss (RPL) remains unclear, but it may be related to a possible genetic predisposition together with involvement of environmental factors. We examined the relation between RPL and polymorphisms in four genes, human aryl hydrocarbon (Ah) receptor, cytochrome P450 (CYP) 1A1, CYP1A2 and CYP1B1, which are involved in the metabolism of a wide range of environmental toxins and carcinogens. All cases and controls were women resident in Sapporo, Japan and the surrounding area. The Ah receptor, CYP1A1, CYP1A2 and CYP1B1 genotypes were assessed in 113 Japanese women with recurrent pregnancy loss (RPL) and 203 ethnically matched women experiencing at least one live birth and no spontaneous abortion (control). No significant differences in Ah receptor, CYP1A1, CYP1A2 and CYP1B1 genotype frequencies were found between the women with RPL and the controls [Ah receptor: Arg/Arg (reference); Arg/Lys and Lys/Lys, odds ratio (OR)=0.67; 95% confidence interval (CI)=0.40-1.11, CYP1A1: m1m1 (reference); m1m2 and m2m2, OR = 0.86; 95% CI = 0.53-1.40, CYP1A2: C/C and C/A (reference); A/A, OR = 1.16; 95% CI = 0.71-1.88, CYP1B1: Leu/Leu (reference); Leu/Val and Val/Val, OR = 1.18; 95% CI = 0.68-2.02]. The present study suggests that the Ah receptor, CYP1A1, CYP1A2 and CYP1B1 gene polymorphisms are not major genetic regulators in RPL.

Abortion, Habitual↗
PubMed2004

Steatosis and fibrosis in patients with chronic hepatitis C.

BACKGROUND: Steatosis is present on liver biopsy in approximately 50% of patients with hepatitis C; its association with stage of fibrosis has been reported, but its relation to other fibrosis associated factors is unknown. AIM: To study the relation between steatosis and other histological features in patients with hepatitis C, and changes in steatosis with time. METHODS: Cross sectional study: 233 routine liver biopsies from 219 patients with hepatitis C; hepatectomy specimens from 65 patients transplanted for hepatitis C cirrhosis. Longitudinal study: 41 patients with two biopsies and 10 patients with three biopsies performed over 2-8 years. Biopsies were scored by the Ishak scheme, and degree of steatosis assessed subjectively. Multivariate analysis was used to study the interaction of fibrosis associated factors. Changes in steatosis over time in individual patients were explored in the longitudinal study. RESULTS: Steatosis was present in 50% of biopsies. It correlated strongly with fibrosis in non-cirrhotic samples, but declined in cirrhosis, and was unusual in transplant hepatectomy specimens. On multivariate analysis of non-cirrhotic biopsies, steatosis was associated with increasing patient age and remained significantly associated with fibrosis independent of portal inflammation and interface hepatitis. In the longitudinal study, steatosis persisted and increased over time, except in patients developing cirrhosis. CONCLUSIONS: Steatosis is associated with fibrosis independently of necroinflammation, but declines in cirrhosis. It may represent a pathogenic pathway distinct from necroinflammatory activity in the generation of liver fibrosis, and should be included in the assessment of biopsies for clinical and research purposes.

Adolescent↗
PubMed2003

Determinants of aflatoxin exposure in young children from Benin and Togo, West Africa: the critical role of weaning.

BACKGROUND: Dietary exposure to high levels of the fungal toxin, aflatoxin, occurs in West Africa, where long-term crop storage facilitates fungal growth. METHODS: We conducted a cross-sectional study in Benin and Togo to investigate aflatoxin exposure in children around the time of weaning and correlated these data with food consumption, socioeconomic status, agro-ecological zone of residence, and anthropometric measures. Blood samples from 479 children (age 9 months to 5 years) from 16 villages in four agro-ecological zones were assayed for aflatoxin-albumin adducts (AF-alb) as a measure of recent past (2-3 months) exposure. RESULTS: Aflatoxin-albumin adducts were detected in 475/479 (99%) children (geometric mean 32.8 pg/mg, 95% CI: 25.3-42.5). Adduct levels varied markedly across agro-ecological zones with mean levels being approximately four times higher in the central than in the northern region. The AF-alb level increased with age up to 3 years, and within the 1-3 year age group was significantly (P = 0.0001) related to weaning status; weaned children had approximately twofold higher mean AF-alb adduct levels (38 pg AF-lysine equivalents per mg of albumin [pg/mg]) than those receiving a mixture of breast milk and solid foods after adjustment for age, sex, agro-ecological zone, and socioeconomic status. A higher frequency of maize consumption, but not groundnut consumption, by the child in the preceding week was correlated with higher AF-alb adduct level. We previously reported that the prevalence of stunted growth (height for age Z-score HAZ) and being underweight (weight for age Z-score WAZ) were 33% and 29% respectively by World Health Organziation criteria. Children in these two categories had 30-40% higher mean AF-alb levels than the remainder of the children and strong dose- response relationships were observed between AF-alb levels and the extent of stunting and being underweight. CONCLUSIONS: Exposure to this common toxic contaminant of West African food increases markedly following weaning and exposure early in life is associated with reduced growth. These observations reinforce the need for aflatoxin exposure intervention strategies within high-risk countries, possibly targeted specifically at foods used in the post-weaning period.

Aflatoxins↗
PubMed2002

Relation between colour vision loss and occupational styrene exposure level.

AIMS: To investigate the relation between colour vision loss and the exposure level of styrene. Exposure level included the current exposure concentration, past cumulative exposure, and the maximum exposure level in the past. METHODS: Colour vision was examined by the Lanthony desaturated panel D-15 test for 76 subjects exposed to styrene in a fibreglass reinforced plastics boat plant (as an exposed group) and 102 non-exposed subjects (as a control group). The current exposure level was expressed by the concentration of atmospheric styrene and end shift urinary mandelic acid (MA) and phenylglyoxylic acid (PGA) levels. The individual cumulative exposure index (CEI) was calculated, based on the exposure frequency and urinary MA concentrations measured for the past eight years. RESULTS: The Colour Confusion Index (CCI) of the exposed group showed a significant difference from the age matched controls. However, only a slight significant relation was found between CCI and the concentration of urinary MA plus PGA. In this study, the exposed group was further divided into two subgroups (as sub-MA+PGA groups) by the median of urinary MA plus PGA of each subject. The dividing line between the subgroups was 0.24 g/g creatinine, which was equivalent to an atmospheric concentration of styrene of about 10 ppm. The CCI values of both the sub-MA+PGA groups were significantly higher than that of the control group. The relation between CCI value and the maximum exposure concentration in the past eight years was examined. It was found that the CCI values of the group with the maximum exposure concentration of styrene over 50 ppm were significantly higher than that of the other groups. CONCLUSIONS: Exposure to styrene would impair colour vision even if the exposure concentration was lower than 10 ppm. Furthermore, if the maximum concentration of styrene exposure transiently exceeded 50 ppm in the past, the styrene related damage might remain. Thus, the safe limit of exposure to styrene and the relation between exposure to styrene and the degree of damage to ocular structure, retina, optic nerve, and brain need to be re-examined.

Adult↗
PubMed2000

Impairment of neurobehavioral function and color vision loss among workers exposed to low concentration of styrene--a review of literatures.

Recently many studies on the health effects of workers who exposed to low-concentration styrene have been published. In this paper firstly we mentioned the reasons why nervous system was critical organ for evaluating the toxicity of organic solvents both in the acute and chronic exposure phases. Then we indicated how neurobehavioral test batteries were useful to detect subclinical adverse health effects of workers exposed to organic solvents. Secondly we reviewed many epidemiological studies on the impairment of neurobehavioral function, i.e., perceptual speed, memory, cognition, personality and mood, and the loss of color vision among styrene workers. Finally, we showed our recent data on the relationship between color vision loss and the concentration of urine metabolites among styrene workers. It can conclude that styrene may cause damage on nervous system, even at the low exposure level such as 50 ppm which used to be the Threshold Limit Value (TLV) recommended by Japan Society for Occupational Health (until 1999) and American Conference of Industrial Hygienists (until 1997).

Affect↗
PubMedDate not supplied

Reduction in exposure to carcinogenic aflatoxins by postharvest intervention measures in west Africa: a community-based intervention study.

BACKGROUND: Aflatoxins are fungal metabolites that frequently contaminate staple foods in much of sub-Saharan Africa, and are associated with increased risk of liver cancer and impaired growth in young children. We aimed to assess whether postharvest measures to restrict aflatoxin contamination of groundnut crops could reduce exposure in west African villages. METHODS: We undertook an intervention study at subsistence farms in the lower Kindia region of Guinea. Farms from 20 villages were included, ten of which implemented a package of postharvest measures to restrict aflatoxin contamination of the groundnut crop; ten controls followed usual postharvest practices. We measured the concentrations of blood aflatoxin-albumin adducts from 600 people immediately after harvest and at 3 months and 5 months postharvest to monitor the effectiveness of the intervention. FINDINGS: In control villages mean aflatoxin-albumin concentration increased postharvest (from 5.5 pg/mg [95% CI 4.7-6.1] immediately after harvest to 18.7 pg/mg [17.0-20.6] 5 months later). By contrast, mean aflatoxin-albumin concentration in intervention villages after 5 months of groundnut storage was much the same as that immediately postharvest (7.2 pg/mg [6.2-8.4] vs 8.0 pg/mg [7.0-9.2]). At 5 months, mean adduct concentration in intervention villages was less than 50% of that in control villages (8.0 pg/mg [7.2-9.2] vs 18.7 pg/mg [17.0-20.6], p<0.0001). About a third of the number of people had non-detectable aflatoxin-albumin concentrations at harvest. At 5 months, five (2%) people in the control villages had non-detectable adduct concentrations compared with 47 (20%) of those in the intervention group (p<0.0001). Mean concentrations of aflatoxin B1 in groundnuts in household stores in intervention and control villages were consistent with measurements of aflatoxin-albumin adducts. INTERPRETATION: Use of low-technology approaches at the subsistence-farm level in sub-Saharan Africa could substantially reduce the disease burden caused by aflatoxin exposure.

Aflatoxin B1↗