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ABSTRACT

Objectives: The present study investigated the relationships of enculturation and depressive symptoms with health risk behavior engagement in Mexican-American college students and examined how these relationships differed by gender. Previous research has noted consistent gender differences in health risk behavior (e.g. alcohol use, substance use, and risky sexual behavior) among Latina/os, and emphasized the role of U.S. acculturation in this difference. Research examining the role of heritage cultural retention (i.e. enculturation), and including the added influence of mental health variables, such as depressive symptoms, is currently lacking. This study sought to address this gap.

Design: A large sample (N?=?677) of Mexican-American college students from four universities (located in New York, California, Florida, and Texas) completed an online questionnaire assessing health risk behaviors and corresponding variables.

Results: We found that males who endorsed more behavioral enculturation and depressive symptoms were more likely to engage in health risk behavior than all others in the sample. Contrary to previous literature, no relationship was found between behavioral enculturation and health risk behavior in females.

Conclusion: The current study found behavioral enculturation to be associated with depressive symptoms, and in turn with health risk behaviors among the males in our sample. Additional research will be needed to identify the mechanism underlying the relationship between enculturation and depressive symptoms as well as between depressive symptoms and risky behavior.  相似文献   
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Platelet α-granules release growth factors (GFs) that promote healing and tissue regeneration. Platelet-rich plasma (PRP) is shown to be beneficial in treating alopecia, and however, clinical response can be inconsistent. Due to several fold enrichment of platelets secreting large quantities of GFs following PRP injections, heterogeneity in amounts of GFs secreted by platelets may contribute to inconsistent clinical responses. Herein, we evaluated factors that could potentially contribute to heterogeneous secretion of GFs by platelets. We measured platelet secretion of transforming growth factor beta1 (TGFβ1), platelet-derived growth factor (PDGF-BB), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF2) in aliquots of de-identified PRP samples from female patients undergoing therapy in the hair disease clinic. Although secretion of GFs by platelets was comparable in PRP samples of patients with non-cicatricial and cicatricial alopecia, a Shapiro-Wilk test for normal distribution indicated significant variability across all patient samples. The amount of GF secreted by platelets was comparable when PRP prepared from two FDA-cleared devices with distinct techniques were compared. We provide evidence of platelets secreting heterogeneous amounts of GFs within each sample as high and low secretion of random factors could be simultaneously detected. These results suggest inherent heterogeneity in secretion of GFs by platelets in patient samples that are not influenced by the device used to prepare PRP. Since some GFs could have antagonistic effects on hair growth, a balance between amounts of growth promoting and inhibiting factors may be crucial in determining clinical response to PRP therapy.  相似文献   
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Inbred mouse strains are the most widely used mammalian model organism in biomedical research owing to ease of genetic manipulation and short lifespan; however, each inbred strain possesses a unique repertoire of deleterious homozygous alleles that can make a specific strain more susceptible to a particular disease. In the current study, we report dystrophic cardiac calcinosis (DCC) in C.B‐17 SCID male mice at 10 weeks of age with no significant change in cardiac function. Acquisition of DCC was characterized by myocardial injury, fibrosis, calcification, and necrosis of the tissue. At 10 weeks of age, 38% of the C.B‐17 SCID mice from two different commercial colonies exhibited significant calcinosis on the ventricular epicardium, predominantly on the right ventricle. The frequency of calcinosis was more than 50% for mice obtained from Taconic's Cambridge City colony and 25% for mice obtained from Taconic's German Town colony. Interestingly, the DCC phenotype did not affect cardiac function at 10 weeks of age. No differences in echocardiography or electrocardiography were observed between the calcinotic and non‐calcinotic mice from either colony. Our findings suggest that C.B‐17 SCID mice exhibit DCC as early as 10 weeks of age with no significant impact on cardiac function. This strain of mice should be cautiously considered for the study of cardiac physiology.  相似文献   
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