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51.
Exposure to various carcinogenic agents along with other contributing factors increase the risk of cancer formation. The current study assesses the effect of soy isoflavones on the biochemical events associated with tumor promotion in mouse skin. 12-O-tetradecanoyl phorbol-13-acetate (TPA), a well-known tumor promoter on topical application depletes the reduced glutathione content (GSH) and down regulates the activities of its metabolizing enzyme, glutathione-S-transferase (GST) and the activities of antioxidant enzymes. However, the ornithine decarboxylase (ODC) activity and unscheduled DNA synthesis are elevated on single topical application of TPA to the dorsal cutaneous portions of the mice. Topical applications of soy isoflavones, half-an-hour prior to the application of TPA prevented the induction of ODC activity and DNA synthesis mediated by TPA (p < 0.01). The content of GSH, GST and antioxidant enzymes (p < 0.05) was also recovered significantly by soy isoflavones in a dose dependent manner. Parallel to these effects, pretreatment with the soy isoflavones also reduced hydrogen peroxide (H2O2) content (p < 0.05) at 1.0 and 2.0 microg/0.2 ml vehicle/animal. Therefore, we conclude that soy isoflavones are potentially protective against TPA induced biochemical alterations.  相似文献   
52.
The aim of this study was to develop films based on β–glucans in association with pomegranate juice for its potential in metabolic disorders such as diabetes due to plenty of bioactive compounds from the film composition. Initially, a Box-Behnken design was generated by varying the level of β–glucan content (0.5, 1, 1.5 g), sodium alginate (0.2, 0.4, 0.6 g) and pomegranate juice (10, 20, 30 mL) for development of films. Subsequently, glycerin was added as 25% of the total dry matter. The optimization of the films prepared by the solvent casting method was conducted based on the different responses such as: water vapor transmission rate (WVTR), water vapor permeability (WVP), thickness, density, moisture content, solubility, film opacity and color. The water activity profile and FT–IR analysis were performed in all tests. The model was used to determine the optimal experimental values considering that the optimal film will make a sustained contribution to diabetes. The optimal values of the film sample made of β–glucans, sodium alginate, pomegranate juice and glycerin make it befitting for packaging dry powdered pharmaceuticals. Finally, antimicrobial activity against Gram-negative and Gram-positive bacteria, UV barrier properties and microcrack and pore detections through SEM were also investigated for the optimal film sample.  相似文献   
53.
The obesity epidemic has serious implications for women of reproductive age; its rising incidence is associated not just with health implications for the mother but also has transgenerational ramifications for the offspring. Increased incidence of diabetes, cardiovascular disease, obesity, and kidney disease are seen in both the mothers and the offspring. Animal models, such as rodent studies, are fundamental to studying maternal obesity and its impact on maternal and offspring health, as human studies lack rigorous controlled experimental design. Furthermore, the short and prolific reproductive potential of rodents enables examination across multiple generations and facilitates the exploration of interventional strategies to mitigate the impact of maternal obesity, both before and during pregnancy. Given that obesity is a major public health concern, it is important to obtain a greater understanding of its pathophysiology and interaction with reproductive health, placental physiology, and foetal development. This narrative review focuses on the known effects of maternal obesity on the mother and the offspring, and the benefits of interventional strategies, including dietary intervention, before or during pregnancy on maternal and foetal outcomes. It further examines the contribution of rodent models of maternal obesity to elucidating pathophysiological pathways of disease development, as well as methods to reduce the impact of obesity on the mothers and the developing foetus. The translation of these findings into the human experience will also be discussed.  相似文献   
54.
Deoxynivalenol (DON) remains one of the most concerning mycotoxins produced by the Fusarium genus due to the wide occurrence in highly consumed cereal-based food and its associated toxicological effects. Previous studies conducted in Spain and other European countries suggested that some vulnerable groups such as children could be exceeding the tolerable daily intakes. Thus, the aim of this study was to conduct a comprehensive and updated dietary exposure assessment study in Spain, with a specific analysis in the region of Catalonia. Cereal-based food samples collected during 2019 were analysed using liquid chromatography coupled to tandem mass spectrometry for multi-mycotoxin detection including DON and its main metabolites and derivatives. Consumption data were gathered from the nation-wide food surveys ENALIA and ENALIA2 conducted in Spain, and a specific survey conducted in Catalonia. The data were combined using deterministic and semi-parametric probabilistic methods. The results showed that DON was widely present in cereal-based food highly consumed in Spain and the Catalonia region. Exposure to DON among the adult population was globally low; however, among infants aged 3–9 years, it resulted in the median of 192 ng/kg body weight/day and the 95th percentiles of 604 ng/kg body weight/day, that would exceed the most conservative safety threshold for infants. Bread and pasta were the main contributing foodstuffs to the global exposure to DON, even among infants; thus, those foods should be considered a priority for food control or to develop strategies to reduce the exposure. In any case, further toxicological and epidemiological studies are required in order to refine the safety thresholds accounting for the sensitivity of the infant population.  相似文献   
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56.
OBJECTIVEIn a large, multiethnic cohort of youths with obesity, we analyzed pathophysiological and genetic mechanisms underlying variations in plasma glucose responses to a 180 min oral glucose tolerance test (OGTT).RESEARCH DESIGN AND METHODSLatent class trajectory analysis was used to identify various glucose response profiles to a nine-point OGTT in 2,378 participants in the Yale Pathogenesis of Youth-Onset T2D study, of whom 1,190 had available TCF7L2 genotyping and 358 had multiple OGTTs over a 5 year follow-up. Insulin sensitivity, clearance, and β-cell function were estimated by glucose, insulin, and C-peptide modeling.RESULTSFour latent classes (1 to 4) were identified based on increasing areas under the curve for glucose. Participants in class 3 and 4 had the worst metabolic and genetic risk profiles, featuring impaired insulin sensitivity, clearance, and β-cell function. Model-predicted probability to be classified as class 1 and 4 increased across ages, while insulin sensitivity and clearance showed transient reductions and β-cell function progressively declined. Insulin sensitivity was the strongest determinant of class assignment at enrollment and of the longitudinal change from class 1 and 2 to higher classes. Transitions between classes 3 and 4 were explained only by changes in β-cell glucose sensitivity.CONCLUSIONSWe identified four glucose response classes in youths with obesity with different genetic risk profiles and progressive impairment in insulin kinetics and action. Insulin sensitivity was the main determinant in the transition between lower and higher glucose classes across ages. In contrast, transitions between the two worst glucose classes were driven only by β-cell glucose sensitivity.  相似文献   
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58.
OBJECTIVE: To present prenatal findings and maternal and neonatal outcomes following second- and early third-trimester spontaneous antepartum uterine rupture events in our institute. METHOD: Charts of patients with full-thickness second- or early third-trimester symptomatic uterine ruptures locally treated between 1984 and 2007 were evaluated. RESULTS: There were seven events involving six women, all requiring emergency laparotomy, and cesarean section (CS). During the study period in our institute, there were 120 636 singleton deliveries (> or =22 weeks' gestation), including 5 of our cases, while in 2 cases, the rupture occurred earlier (<22 weeks' gestation). The rupture occurred after > or = 1 previous CSs in five cases. Six events were associated with abnormal placentation: placenta previa (n = 3), placenta percreta (n = 1), or both (n = 2). Other associated events included short, interpregnancy (IP) interval (n = 3) and past uterine rupture (n = 2). Pregnant women at gestational age > or = 22 weeks, who had the combination of placenta previa, and previous CS (n = 3), had a higher chance for spontaneous symptomatic antepartum uterine rupture when compared to women with placenta previa without a previous CS (OR 29.3, 95% CI 1.5-569.3, p = 0.007). There were no maternal deaths. Three of the five viable neonates survived. CONCLUSIONS: Spontaneous symptomatic second- or early third-trimester uterine rupture in nonlaboring women is a very rare, obstetric emergency, which is hard to diagnose. Maternal and neonatal outcomes can be optimized by awareness of risk factors, recognition of clinical signs and symptoms, and availability of ultrasound to assist in establishing diagnosis, and enabling prompt surgical intervention.  相似文献   
59.
Abstract Objective: The receptor for advanced glycation end products (RAGE) has been proposed to participate in the innate and adaptive immune responses. RAGE can induce production of pro-inflammatory cytokines and chemokines, as well as neutrophil chemotaxis in a manner that may be suppressed or stimulated by soluble, truncated forms of RAGE including the soluble form of RAGE (sRAGE) and endogenous secretory RAGE (esRAGE). The objective of this study was to determine whether intra-amniotic infection/inflammation (IAI) is associated with changes in the amniotic fluid concentration of sRAGE and esRAGE. Study design: Amniotic fluid (AF) was retrieved from patients in the following groups: 1) mid-trimester (14-18 weeks of gestation; n=68); 2) term not in labor (n=24); 3) term in labor (n=51); 4) preterm labor and intact membranes (n=124); and 5) preterm PROM (n=80). Intra-amniotic infection and inflammation were defined as the presence of a positive amniotic fluid culture for microorganisms and an AF interleukin-6 concentration >/=2.6 ng/mL, respectively. The AF concentration of sRAGE and esRAGE were determined using specific and sensitive ELISAs which measured total immunoreactive sRAGE and esRAGE, respectively. Patients were matched for gestational age at amniocentesis to compare the AF concentration of sRAGE and esRAGE in patients with and without IAI. Non-parametric statistics were used for analysis and a P<0.05 was considered significant. Results: 1) Patients at term not in labor had higher median AF concentrations of sRAGE and esRAGE than those in the mid-trimester (P<0.001 for both comparisons) and those at term in labor (P=0.03 and P=0.04, respectively); 2) patients with preterm labor and intact membranes with intra-amniotic infection/inflammation (IAI) had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.02 and P=0.005, respectively); 3) similarly, patients with preterm PROM with IAI had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.03 and P=0.02, respectively). Conclusion: Intra-amniotic infection/inflammation is associated with increased amniotic fluid concentrations of sRAGE and esRAGE. Changes in the amniotic fluid concentration of sRAGE and esRAGE may represent part of the immune response to intra-amniotic infection/inflammation.  相似文献   
60.
Several studies have explored the disproportionate number of children of color involved in child protective services, raising concerns that racial bias in the system results in more women of color being referred to child protection. The authors conducted a case series to analyze whether a woman's race and ethnicity influenced referrals to child protective services in a domestic violence context. Data were obtained through interview records of 263 women (38% women of color) at a Minneapolis-based advocacy and therapy organization. The findings suggest that women who face multiple forms of oppressions may have greater risk of being involved with child protection services.  相似文献   
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