Biomedical subjects

Lisa C Konick

Publications and source records attributed to Lisa C Konick.

3 recordsLinked to original sources

PubMed2005

What role does race play in adolescent suicidal ideation?

Epidemiological data indicate that suicide rates have been decreasing among 15-19-year-olds in the United States; however, rates have been increasing among some minority groups. Research has identified numerous risk factors for adolescent suicide and suicide-related behaviors, but models testing these risk factors within different racial or ethnic groups are scarce. The current study tested a model of adolescent suicide ideation in a sample of 258 high school students, comparing the model fit across two racial groups. The model significantly fit the data for both groups indicating that the relationship between suicide exposure and current suicidal ideation is mediated by reasons for living and level of depressive symptoms. Ways in which the results improve our understanding of risk factors in diverse adolescents are discussed.

Adolescent↗

PubMed2005

Testing a model of suicide ideation in college students.

This study examined several risk factors-negative life events (NLE), hopelessness, and depressive symptoms-believed to commonly precipitate suicide ideation in college students. A total of 345 undergraduates participated in the study. Students completed four self-report questionnaires. Hierarchical regression analyses were used to construct a risk model of suicide ideation. This study confirmed depressive symptoms and hopelessness as predictors of suicide ideation in college students; however, NLE impacted suicidal thoughts through hopelessness and depressive symptoms. Interestingly, depressive symptoms exerted a stronger influence on suicide ideation than hopelessness. Hopelessness served as a partial mediator in the relationship between NLE and depressive symptoms; however, depressive symptoms fully mediated the relationship between NLE and hopelessness. Clinical implications for understanding suicide risk in college students are discussed.

Adolescent↗

PubMed2004

Cellular changes in the postmortem hippocampus in major depression.

BACKGROUND: Imaging studies report that hippocampal volume is decreased in major depressive disorder (MDD). A cellular basis for reduced hippocampal volume in MDD has not been identified. METHODS: Sections of right hippocampus were collected in 19 subjects with MDD and 21 normal control subjects. The density of pyramidal neurons, dentate granule cell neurons, glia, and the size of the neuronal somal area were measured in systematic, randomly placed three-dimensional optical disector counting boxes. RESULTS: In MDD, cryostat-cut hippocampal sections shrink in depth a significant 18% greater amount than in control subjects. The density of granule cells and glia in the dentate gyrus and pyramidal neurons and glia in all cornv ammonis (CA)/hippocampal subfields is significantly increased by 30%-35% in MDD. The average soma size of pyramidal neurons is significantly decreased in MDD. CONCLUSION: In MDD, the packing density of glia, pyramidal neurons, and granule cell neurons is significantly increased in all hippocampal subfields and the dentate gyrus, and pyramidal neuron soma size is significantly decreased as well. It is suggested that a significant reduction in neuropil in MDD may account for decreased hippocampal volume detected by neuroimaging. In addition, differential shrinkage of frozen sections of the hippocampus suggests differential water content in hippocampus in MDD.

Adult↗