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American Indian and Alaska Native (AIAN) individuals are diverse culturally and geographically but share a high prevalence of chronic illness, largely because of obstacles to high-quality health care. The authors comprehensively examined cancer incidence and mortality among non-Hispanic AIAN individuals, compared with non-Hispanic White individuals for context, using population-based data from the National Cancer Institute, the Centers for Disease Control and Prevention, and the North American Association of Central Cancer Registries. Overall cancer rates among AIAN individuals were 2% higher than among White individuals for incidence (2014 through 2018, confined to Purchased/Referred Care Delivery Area counties to reduce racial misclassification) but 18% higher for mortality (2015 through 2019). However, disparities varied widely by cancer type and geographic region. For example, breast and prostate cancer mortality rates are 8% and 31% higher, respectively, in AIAN individuals than in White individuals despite lower incidence and the availability of early detection tests for these cancers. The burden among AIAN individuals is highest for infection-related cancers (liver, stomach, and cervix), for kidney cancer, and for colorectal cancer among indigenous Alaskans (91.3 vs. 35.5 cases per 100,000 for White Alaskans), who have the highest rates in the world. Steep increases for early onset colorectal cancer, from 18.8 cases per 100,000 Native Alaskans aged 20–49 years during 1998 through 2002 to 34.8 cases per 100,000 during 2014 through 2018, exacerbated this disparity. Death rates for infection-related cancers (liver, stomach, and cervix), as well as kidney cancer, were approximately two-fold higher among AIAN individuals compared with White individuals. These findings highlight the need for more effective strategies to reduce the prevalence of chronic oncogenic infections and improve access to high-quality cancer screening and treatment for AIAN individuals. Mitigating the disparate burden will require expanded financial support of tribal health care as well as increased collaboration and engagement with this marginalized population.  相似文献   
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PurposeIdentification of women with hereditary forms of cancer allows for precision medicine approaches to improve survival. Non-Hispanic Black (NHB) women in the US general population are less likely to undergo genetic testing or utilize risk-reducing strategies. Whether these disparities exist within the equal-access US military healthcare system is not known.MethodsGenetic test information and surgical procedures were extracted for all NHB and Non-Hispanic Whites (NHW) with invasive breast cancer. National Comprehensive Cancer Network criteria from the year of diagnosis were assessed for all patients. Data were analyzed using chi-square analysis with P < .05 defining significance.ResultsNHB were significantly (P = .009) more likely to meet criteria for genetic testing compared to NHW, however, test uptake did not differ significantly between populations (P = .292). While 81% of both populations with BRCA1/2 pathogenic variants elected for double mastectomy, NHW were two times more likely to undergo risk-reducing bilateral salpingo-oophorectomy.ConclusionThese data demonstrate that when barriers, such as cost and lack of insurance, were removed, NHB were as willing to pursue testing as their NHW counterparts. Increasing the availability of testing and clinical management for NHB with hereditary forms of cancer may help reduce disparate survival seen in the US general population.  相似文献   
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Objective

Suicide is the second-leading cause of death in youth. We tested whether having a mentoring relationship associated with lower risks for suicidality, particularly among youth at higher risk due to cyberbullying.

Methods

This study pooled the 2017 Youth Risk Behavior Survey (YRBS) data from five jurisdictions that asked students if there was at least one teacher or other adult in their school that they could talk with, if they have a problem (mentorship). Students self-reported cyberbullying exposure and suicidality in the past 12 months. Odds of suicidal ideation, planning, and attempts were estimated using multivariable weighted logistic regression in overall and sex-stratified stepwise models. Interactions between mentorship and cyberbullying were also tested.

Results

Of the 25,527 student respondents, 87% reported having a mentoring relationship. Mentoring relationships were associated with lower odds of suicidal ideation (aOR, 0.44; 95% CI 0.33–0.57), planning (aOR, 0.59; 95% CI 0.41–0.85), and suicide attempts (aOR, 0.42; 95% CI 0.31–0.56). Stratified analyses showed a significant interaction between cyberbullying and mentorship with suicidal attempts among males, and a near-significant association between cyberbullying and mentorship with suicidal thoughts among females. Compared to male students with no cyberbullying and no mentorship, odds of attempting suicide were lower for males with no cyberbullying and mentorship (aOR, 0.55, 95% CI 0.32–0.92), higher for males with cyberbullying and no mentorship (aOR, 7.78, 95% CI 3.47–17.47), but not significantly different for males with cyberbullying and mentoring relationships (aOR, 1.49, 95% CI 0.86–2.48). Similarly, compared with females with no cyberbullying and no mentorship, odds of having suicidal thoughts were lower for females with no cyberbullying and mentorship (aOR, 0.40, 95% CI 0.28–0.57), and higher for females with cyberbullying and no mentorship (aOR, 2.54, 95% CI 1.59–4.07).

Conclusion

School-based mentoring may mitigate risk of suicidality among adolescents and limit the toxic effects of cyberbullying.

  相似文献   
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Purpose

Previous research has identified social support to be associated with risk of posttraumatic stress disorder (PTSD) symptoms among military personnel. While the lack of social support influences PTSD symptomatology, it is unknown how changes in perceived social support affect the PTSD symptom level in the aftermath of deployment. Furthermore, the influence of specific sources of social support from pre- to post-deployment on level of PTSD symptoms is unknown. We aim to examine how changes in perceived social support (overall and from specific sources) from pre- to 2.5 year post-deployment are associated with the level of post-deployment PTSD symptoms.

Methods

Danish army military personnel deployed to Afghanistan in 2009 and 2013 completed questionnaires at pre-deployment and at 2.5 year post-deployment measuring perceived social support and PTSD symptomatology and sample characteristics of the two cohorts. Data were analyzed using univariate and multivariate nominal logistic regression.

Results

Negative changes in perceived social support from pre- to post-deployment were associated with both moderate (OR 1.99, CI 1.51–2.57) and high levels (OR 2.71, CI 1.94–3.78) of PTSD symptoms 2.5 year post-deployment (adjusted analysis). Broadly, the same direction was found for specific sources of social support and level of PTSD symptoms. In the adjusted analyses, pre-deployment perceived social support and military rank moderated the associations.

Conclusions

Deterioration in perceived social support (overall and specific sources) from pre- to 2.5 year post-deployment increases the risk of an elevated level of PTSD symptoms 2.5 year post-deployment.

  相似文献   
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The notarium is a rigid bony structure, which resulted from the fusion of thoracic vertebrae of some pterosaurs and birds. It is high variable, ranging from two to six fused thoracic vertebrae. In this study, we reviewed and analyzed approximately 270 specimens of neornithine birds (representing 80% of the living orders) and some fossils in order to identify the number of fused vertebrae, degree and sites of vertebral fusion, occurrence of sutures, and other structures of potential phylogenetic and functional significance. These data were analyzed using a recent time-calibrated molecular phylogenetic tree and principal component analyses analysis evaluating the relationship with long bones in order to reconstruct macroevolutionary trends related to the evolution of the notarium. The occurrence of this structure shows a mosaic distribution over neornithine phylogeny, originating several times independently, especially during the Paleogene, in predominantly ground-dwelling forms. The notarium of these groups is characterized by: neural spines fused into single structure, intervertebral openings small to absent, large ventral keels forming ventral plates, and fused transverse processes. Derived neornithines, such as aquatic forms and long-legged birds, have a tendency to display a decreased degree of fusion between the vertebrae, which may indicate a reduction or disappearance of the notarium.  相似文献   
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