RESUMO
Tritan copolyester is a novel plastic form from Eastman Company utilizing three main monomers, 1,4-cyclohexanedimethanol (CHDM), dimethyl terephthalate (DMT), and 2,2,4,4-tetramethyl-1,3-cyclobutanediol. Despite Tritan has been widely applied for plastic bottles, the effects of long-term exposure to these compounds have seldom been investigated. We investigated chronic effects and endocrine disruption potential of CHDM and terephthalic acid (TPA), main mammalian metabolite formed from DMT, using crustacean Daphnia magna and Moina macrocopa, and freshwater fish (Oryzias latipes). The effects on sex hormone balance and the associated mechanisms were also investigated by use of H295R cells. In chronic toxicity test, D. magna showed significant decrease in reproduction (number of young per female) after exposure to 10 mg/L TPA. In early life stage exposure using O. latipes, significant decrease of juvenile survival and weight were observed in fish exposed to 10 mg/L and ≥1 mg/L CHDM, respectively. Expressions of vtg2 mRNA in fish exposed to CHDM and those of cyp19b, star, cyp17, and cyp19a mRNAs in fish exposed to TPA were significantly up-regulated. The results of H295R cell assay also showed that both chemicals at high concentrations could alter sex hormone production in steroidogenic pathway. The effective concentrations of the tested compounds were several orders of magnitude greater than the concentrations can be detected in ambient waters. Further in vivo and in vitro studies will be needed to investigate the effect of co-polymer on endocrine disruption.
Assuntos
Cladocera/efeitos dos fármacos , Cicloexanos/metabolismo , Disruptores Endócrinos/toxicidade , Oryzias/metabolismo , Ácidos Ftálicos/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Linhagem Celular Tumoral , Daphnia/efeitos dos fármacos , Feminino , Humanos , Masculino , Poliésteres/metabolismo , Testes de Toxicidade CrônicaRESUMO
OBJECTIVE: To analyze the relationship between brain lesion location and type of chronic dysphagia in patients with supratentorial stroke. METHODS: Data from 82 chronic stroke patients who underwent videofluoroscopic swallowing studies at >6 months after an initial stroke event were retrospectively analyzed. Delayed oral transit time, delayed pharyngeal transit time, and the presence of aspiration were extracted. A voxel-based lesion symptom mapping (VLSM) analysis was used to correlate types of dysphagia with specific brain lesions. RESULTS: VLSM identified several clusters of voxels that significantly correlated with type of dysphagia. Delayed oral transit time mainly correlated with lesions in the left inferior frontal lobe and precentral gyrus; delayed pharyngeal time mainly correlated with lesions in the right basal ganglia and corona radiate; and aspiration was mainly correlated with lesions in the putamen. CONCLUSION: Understanding the association between lesion location and dysphagia in chronic stroke patients is an important first step towards predicting permanent dysphagia after stroke. Improved understanding of the neural correlates of dysphagia will inform the utility of interventions for its treatment and prevention after stroke.
RESUMO
OBJECTIVE: To investigate risk factors for diabetic peripheral polyneuropathy and their correlation with the quantified severity of nerve dysfunction in patients with diabetes mellitus (DM). METHODS: A total of 187 diabetic patients with clinically suspected polyneuropathy (PN) were subclassified into 2 groups according to electrodiagnostic testing: a DM-PN group of 153 diabetic patients without electrophysiological abnormality and a DM+PN group of 34 diabetic patients with polyneuropathy. For all patients, age, sex, height, weight, duration of DM, and plasma glycosylated hemoglobin (HbA1c) level were comparatively investigated. A composite score was introduced to quantitatively analyze the results of the nerve conduction studies. Logistic regression analysis and multiple regression analysis were used to evaluate correlations between significant risk factors and severity of diabetic polyneuropathy. RESULTS: The DM+PN group showed a significantly higher HbA1c level and composite score, as compared with the DM-PN group. Increased HbA1c level and old age were significant predictive factors for polyneuropathy in diabetic patients (odds ratio=5.233 and 4.745, respectively). In the multiple linear regression model, HbA1c and age showed a significant positive association with composite score, in order (ß=1.560 and 0.253, respectively). CONCLUSION: Increased HbA1c level indicative of a state of chronic hyperglycemia was a risk factor for polyneuropathy in diabetic patients and a quantitative measure of its severity.
RESUMO
Benzophenones (BPs) have been used as sunscreen agents and as ultraviolet stabilizers in plastic surface coatings for food packaging. However, few studies have been performed to examine the level of human exposure to BPs and the potential sources of such exposure. We evaluated the exposure levels to six major BPs (BP-1, BP-2, BP-3, BP-4, BP-8, and 4-hydroxybenzophenone (4-OH-BP)) among the adult population in two cities in Korea, and investigated the potential dietary sources of the BPs. Urinary levels of malondialdehyde (MDA) as an oxidative stress biomarker as well as their association with the levels of BPs were also analyzed. Among the six BPs analyzed, 4-OH-BP, BP-1, BP-3, and BP-4 were detected in 77%, 49%, 27%, and 21% of the population, respectively. BP concentrations were relatively higher in younger (people in their 20s and 30s) cosmetic users and leaner women. Even after the adjustment of age, body mass index, and cosmetic use, the consumption of frozen storage food, instant noodles, and instant coffee was significantly correlated with urinary BPs, and these associations were sex-dependent. No significant correlation was observed between the levels of BPs and levels of MDA. The results of the present study will be useful for developing plans of public health management of BPs.
Assuntos
Benzofenonas/urina , Dieta , Alimentos , Estresse Oxidativo , Adulto , Biomarcadores/urina , Exposição Ambiental/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da CoreiaRESUMO
OBJECTIVE: To investigate the shoulder disease patterns for the table-tennis (TT) and archery (AR) wheelchair athletes via ultrasonographic evaluations. METHODS: A total of 35 wheelchair athletes were enrolled, made up of groups of TT (n=19) and AR (n=16) athletes. They were all paraplegic patients and were investigated for their wheelchair usage duration, careers as sports players, weekly training times, the Wheelchair User's Shoulder Pain Index (WUSPI) scores and ultrasonographic evaluation. Shoulders were divided into playing arm of TT, non-playing arm of TT, bow-arm of AR, and draw arm of AR athletes. Shoulder diseases were classified into five entities of subscapularis tendinopathy, supraspinatus tendinopathy, infraspinatus tendinopathy, biceps long head tendinopathy, and subacromial-subdeltoid bursitis. The pattern of shoulder diseases were compared between the two groups using the Mann-Whitney and the chi-square tests. RESULTS: WSUPI did not significantly correlate with age, wheelchair usage duration, career as players or weekly training times for all the wheelchair athletes. For the non-playing arm of TT athletes, there was a high percentage of subscapularis (45.5%) and supraspinatus (40.9%) tendinopathy. The percentage of subacromial-subdeltoid bursitis showed a tendency to be present in the playing arm of TT athletes (20.0%) compared with their non-playing arm (4.5%), even though this was not statistically significant. Biceps long head tendinopathy was the most common disease of the shoulder in the draw arm of AR athletes, and the difference was significant when compared to the non-playing arm of TT athletes (p<0.05). CONCLUSION: There was a high percentage of subscapularis and supraspinatus tendinopathy cases for the non-playing arm of TT wheelchair athletes, and a high percentage of biceps long head tendinopathy for the draw arm for the AR wheelchair athletes. Consideration of the biomechanical properties of each sport may be needed to tailor specific training for wheelchair athletes.