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1.
Arthropod Struct Dev ; 47(4): 442-448, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29339328

RESUMO

Adult dragonflies can be divided into two major groups, perchers and fliers, exhibiting notably different flight behaviour. Previous studies have yielded conflicting results regarding the link between the wing macro-morphology and flight style in these two groups. In this study, we present the first systematic investigation of the micro-morphological differences of wings of percher and flier dragonflies in four closely related species from the family Libellulidae. Our results suggest that the shape and material composition of wing microstructural components and, in particular, the nodus are adapted to facilitate the specific wing functioning in fliers and perchers. The findings further indicate a decreasing trend in the area proportion of the soft resilin-dominated cuticle in the nodus in the series of species from typical perchers to typical fliers. Such a reduction in the resilin proportion in the nodus of fliers is associated with an increase in the wing aspect ratio. The knot-shaped protrusion at the nodus of perchers, which becomes notably smaller in that of strong fliers, is likely to act as a mechanical stopper, avoiding large wing displacements. This study aims to develop a novel framework for future research on the relationship between wing morphology and flight behaviour in dragonflies.


Assuntos
Voo Animal , Odonatos/anatomia & histologia , Odonatos/fisiologia , Asas de Animais/anatomia & histologia , Adaptação Biológica , Animais , Fenômenos Biomecânicos , Masculino , Especificidade da Espécie
2.
Acta Biomater ; 60: 330-338, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28739543

RESUMO

Dragonfly wings are highly specialized locomotor systems, which are formed by a combination of several structural components. The wing components, also known as structural elements, are responsible for the various aspects of the wing functionality. Considering the complex interactions between the wing components, modelling of the wings as a whole is only possible with inevitable huge oversimplifications. In order to overcome this difficulty, we have recently proposed a new approach to model individual components of complex wings comparatively. Here, we use this approach to study nodus, a structural element of dragonfly wings which has been less studied to date. Using a combination of several imaging techniques including scanning electron microscopy (SEM), wide-field fluorescence microscopy (WFM), confocal laser scanning microscopy (CLSM) and micro-computed tomography (micro-CT) scanning, we aim to characterize the spatial morphology and material composition of fore- and hindwing nodi of the dragonfly Brachythemis contaminata. The microscopy results show the presence of resilin in the nodi, which is expected to help the deformability of the wings. The computational results based on three-dimensional (3D) structural data suggest that the specific geometry of the nodus restrains its displacements when subjected to pressure on the ventral side. This effect, resulting from an interlocking mechanism, is expected to contribute to the dorso-ventral asymmetry of wing deformation and to provide a higher resistance to aerodynamic forces during the downstroke. Our results provide an important step towards better understanding of the structure-property-function relationship in dragonfly wings. STATEMENT OF SIGNIFICANCE: In this study, we investigate the wing nodus, a specialized wing component in dragonflies. Using a combination of modern imaging techniques, we demonstrate the presence of resilin in the nodus, which is expected to facilitate the wing deformability in flight. The specific geometry of the nodus, however, seems to restrain its displacements when subjected to pressure on the ventral side. This effect, resulting from an interlocking mechanism, is suggested to contribute to dorso-ventral asymmetry of wing deformations and to provide a higher resistance to aerodynamic forces during the downstroke. Our results provide an important step towards better understanding of the structure-property-function relationship in dragonfly wings and might help to design more efficient wings for biomimetic micro-air vehicles.


Assuntos
Voo Animal/fisiologia , Modelos Biológicos , Odonatos , Asas de Animais , Animais , Odonatos/anatomia & histologia , Odonatos/fisiologia , Asas de Animais/diagnóstico por imagem , Asas de Animais/fisiologia
3.
AIDS Care ; 21(8): 1000-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20024756

RESUMO

Recent studies support technology-based behavioral interventions for individuals with HIV. This study focused on the use of cell phone and internet technologies among a cohort of 515 HIV-infected individuals. Socio-demographic and clinic data were collected among individuals presenting at an urban Midwestern university HIV clinic in 2007. Regular internet usage occurred more often with males, Caucasians, those who were employed, had higher income, and were more educated. Higher levels of education and income >$10,000 predicted regular usage when controlling for race, employment, and gender. Cell phone ownership was associated with being Caucasian, employed, more educated, and salary >$10,000. Employment was the only predictor of owning a cell phone when controlling for income, race, and education. Individuals who were <40 years of age, employed, and more educated were more likely to know how to text message. Employment and post-high school education predicted knowledge of text messaging, when controlling for age. Disparities among internet, cell phone, and text messaging usage exist among HIV-infected individuals.


Assuntos
Telefone Celular/estatística & dados numéricos , Infecções por HIV/terapia , Internet/estatística & dados numéricos , Negro ou Afro-Americano/estatística & dados numéricos , Estudos Transversais , Escolaridade , Feminino , Habitação , Humanos , Renda , Masculino , Estado Civil , Missouri , Cooperação do Paciente , Saúde da População Urbana , População Branca/estatística & dados numéricos
4.
AIDS Patient Care STDS ; 23(11): 949-55, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19925308

RESUMO

Individuals with HIV experience fluctuating levels of distress throughout the course of HIV infection. This study was conducted to examine the associations of depressive symptomatology with HIV disease in a cohort of individuals who are engaged in routine medical care. This cross-sectional study examined the prevalence of depressive symptoms that were measured as part of a standard of care behavioral assessment among individuals at an urban HIV clinic in the Midwest. Demographic characteristics, depressive symptoms, and behavioral risk factors were collected. A total of 514 individuals participated in the study, the majority of whom was male and African American. One quarter of the sample endorsed symptoms of other depressive disorder, while 18% (n = 91) endorsed symptoms of major depressive disorder as measured by the Patient Health Questionnaire-9 (PHQ-9). Among those on highly active antiretroviral therapy (HAART), individuals who were unemployed (adjusted odds ratio [AOR] = 2.47, 95% confidence interval [CI] = 1.54, 3.97), had a minor dependent (AOR = 2.17, 95% CI = 1.25, 3.77), or between the ages of 18 and 34 years (AOR = 1.37, CI = 1.03, 1.94) and detectable HIV viral load (AOR = 2.52, 95% CI = 1.22, 5.23) were more likely to report depressive disorder symptoms when controlling for age, gender, race, and education. Nearly 15% of the sample endorsed having suicidal thoughts at least once in the past two weeks. Regardless of HAART prescription, individuals who were unemployed had a higher likelihood of expressing suicidal ideation (AOR = 3.43, 95% CI = 1.66, 7.06). Given the association between depressive symptomatology and poor rates of HIV viral suppression, screening and appropriate interventions for depressive symptoms are warranted in the HIV outpatient setting to improve outcomes.


Assuntos
Depressão/diagnóstico , Transtorno Depressivo/diagnóstico , Infecções por HIV/complicações , Programas de Rastreamento/métodos , Adolescente , Adulto , Terapia Antirretroviral de Alta Atividade , Estudos Transversais , Depressão/complicações , Depressão/epidemiologia , Depressão/fisiopatologia , Transtorno Depressivo/complicações , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/fisiopatologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1 , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
5.
Nervenarzt ; 78(6): 665-71, 2007 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-16821064

RESUMO

BACKGROUND: Inpatient treatment is the most costly sector of treatment for depressive disorders in Germany. However, little is known about which patient and hospital characteristics contribute to costs of inpatient episodes. PATIENTS AND METHODS: To take part in this study, patients had to fullfill criteria for ICD-10 diagnosis of F31.3-F31.5, F32, F33, F34.1, F43.20, or F43.21. Episodes were recorded between September 9 2001 and March 3 2003 in ten hospitals in three German states. Inpatient records of 1,202 persons were analysed. Multiple regression analysis was performed to identify significant patient predictors of cost per inpatient episode, and the predictive function of hospital characteristics was analysed by applying hierarchical linear modeling. RESULTS: Patient characteristics at admission could not explain a substantial part of the variance in episode costs. Better prediction was possible including variables from the whole treatment process. Also, conditions for admission and patient-related factors did not well explain cost differences between hospitals, but characteristics of the whole treatment were. CONCLUSION: For predicting costs of inpatient depressive episodes, the complete course treatment has to be considered. As in the physiologic sector, therapeutic and diagnostic procedures have a great effect on cost prediction.


Assuntos
Transtorno Depressivo/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Recursos em Saúde/economia , Hospitalização/economia , Programas Nacionais de Saúde/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Custos e Análise de Custo , Transtorno Depressivo/terapia , Cuidado Periódico , Feminino , Alemanha , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estatística como Assunto , Gestão da Qualidade Total/economia
6.
Am J Med ; 108(1): 54-64, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11059441

RESUMO

PURPOSE: Several medications have recently been introduced for the treatment of depression. We reviewed the literature to summarize their efficacy in the treatment of depression in adult patients in primary care settings. METHODS: We searched the literature published from 1980 to January 1998 using the Cochrane Collaboration Depression Anxiety and Neurosis Group's specialized registry of 8,451 clinical trials, references from trials and 46 pertinent meta-analyses, and consultation with experts. We included randomized controlled trials of at least 6 weeks' duration that measured clinical outcomes and compared one of 32 newer medications with another newer antidepressant, an older antidepressant, a placebo, or a psychosocial intervention for the treatment of depressed patients in primary care settings. The primary outcome was response rate, defined as the proportion of patients experiencing a 50% or greater improvement in depressive symptoms. RESULTS: There were 28 randomized controlled trials involving 5,940 adult primary care patients with major depression, depression requiring treatment, dysthymia, or mixed anxiety depression. Newer agents, including selective serotonin re-uptake inhibitors, serotonin norepinephrine inhibitors, reversible inhibitors of monoamine oxidase, and dopamine antagonists, were usually compared with tricyclic agents. Average response rates were 63% for newer agents, 35% for placebo, and 60% for tricyclic agents. Newer agents were significantly more effective than placebo [risk ratio = 1.6; 95% confidence interval (CI), 1.2 to 2.1), but similar to tricyclic agents (risk ratio = 1.0; 95% CI, 0.9 to 1.1). Response rates were similar in the different types of depressive disorders, except that two small trials in frail older patients showed no significant effects of newer agents compared with placebo. Dropout rates as a result of adverse effects were 8% with newer agents and 13% with tricyclic agents (P <0.05). CONCLUSIONS: In primary care settings, newer antidepressants are more effective than placebo and have similar efficacy compared with tricyclic agents in the acute treatment of depression. Dropout rates as a result of adverse effects are lower with newer compared with tricyclic agents. Future studies should compare the effectiveness of different therapies among primary care patients with less severe depression and greater medical and psychiatric comorbidity.


Assuntos
Antidepressivos de Segunda Geração/uso terapêutico , Depressão/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Atenção Primária à Saúde , Antidepressivos de Segunda Geração/classificação , Antagonistas de Dopamina/uso terapêutico , Inibidores da Captação de Dopamina/uso terapêutico , Medicina Baseada em Evidências , GABAérgicos/uso terapêutico , Humanos , Hypericum/uso terapêutico , Inibidores da Monoaminoxidase/uso terapêutico , Fitoterapia , Plantas Medicinais , Viés de Publicação , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Agonistas do Receptor de Serotonina/uso terapêutico , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Estados Unidos
9.
Psychopharmacol Bull ; 34(4): 409-795, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10513454

RESUMO

OBJECTIVES: Depressive disorders are persistent, recurring illnesses that impose enormous personal suffering on individuals and their families. Major depression alone is estimated as the fourth most important cause of worldwide loss in disability-adjusted life years and is likely to become the second most important within 20 years. A continued quest for more effective treatments has spawned newer antidepressants and herbal treatments, which have contributed to explosive growth in antidepressant prescribing, increasing pharmacy costs, and wider but sometimes confusing choices for clinicians and patients. This evidence report provides a comprehensive evaluation of the benefits and adverse effects of newer pharmacotherapies and herbal treatments for depressive disorders in adults and children. SEARCH STRATEGY: Pertinent literature from 1980 to January 1998 was identified from a specialized registry of controlled trials, meta-analyses, and experts. The registry contained trials addressing depression that had been identified from multiple electronic bibliographic databases, hand searches of journals, and pharmaceutical companies. The search, which yielded 1,277 records, combined terms "depression," "depressive disorder," or "dysthymic disorder" with a list of 32 specific "newer" antidepressant and herbal treatments. SELECTION CRITERIA: Randomized controlled trials were reviewed if they (1) were at least 6 weeks in duration; (2) compared a "newer" antidepressant with another antidepressant (newer or older), placebo, or psychosocial intervention; (3) involved participants with depressive disorders; and (4) had a clinical outcome. Two or more independent reviewers identified 315 trials that met these criteria. DATA COLLECTION AND ANALYSIS: Two persons independently abstracted data from each trial. Data were synthesized descriptively, paying attention to participant and diagnostic descriptors, intervention characteristics, study designs and clinical outcomes. Some data were analyzed quantitatively using an empirical Bayes random-effects estimator method. Primary outcomes were response rate, total discontinuation rates (dropouts), and discontinuation rates due to adverse events. Response rates were defined as a 50 percent or greater improvement in symptoms as assessed by a depression symptoms rating scale or a rating of much or very much improved as assessed by a global assessment method. MAIN RESULTS: There were 264 trials that evaluated antidepressants in patients (adults and children) with major depression. Of these, 81 compared newer agents with placebo, 150 newer with older agents, 32 newer agents with newer agents, and 1 newer agent with psychotherapy. There were 14 trials evaluating hypericum (St. John's wort), 27 trials each in primary care patients and older adults, 10 trials limited to patients with specific concomitant illnesses, 9 trials in patients with dysthymia, 3 trials each in patients with mixed anxiety depression and subsyndromal depression, 2 trials in adolescents, and 1 in the postpartum setting. Most trials were conducted in outpatients and examined only acute phase treatment of less than 12 weeks' duration. Newer antidepressants were more effective than placebo in treating major depression (risk ratio 1.6, 95% CI 1.5 to 1.7) and dysthymia (risk ratio 1.7, 95% CI 1.3 to 2.3). They were effective among older adults and in primary care patients. In general, there were no significant differences in efficacy among individual newer agents or between newer and older agents. Hypericum (St. John's wort) was more effective than placebo in treating mild to moderately severe depressive disorders (risk ratio 1.9, 95% CI 1.2 to 2.8). Whether hypericum (St. John's wort) is as effective as standard antidepressant agents given in adequate doses was not established. No significant differences were found between newer and older antidepressants in overall discontinuation rates. Selective serotonin reuptake inhibitors (SSRIs), reversi


Assuntos
Antidepressivos de Segunda Geração/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Adulto , Criança , Transtorno Depressivo/psicologia , Medicina Baseada em Evidências , Humanos
10.
J Natl Cancer Inst Monogr ; (18): 117-22, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8562211

RESUMO

A theory-based program that used peer modeling and a network of peer communicators to promote breast and cervical cancer screening was designed and implemented in a barrio of San Antonio with a population of approximately 25,000 adult women. The implementation process was evaluated and documented through field notes, archival documents, content analyses, interviews, surveys, etc. Over a 21-month period, a total of 156 new stories and a network for distribution of more than 80,000 print pieces carried messages about positive role models who were receiving Pap smears and mammograms. A group of 85 volunteers were recruited to promote screening; these volunteers reached 2000-3000 women each month with personal contacts in which cancer screening was encouraged. A small group of volunteers offered particularly intensive assistance to their peers, e.g., helping them to make and keep appointments for screening examinations. The theoretical communication model for the program, which maximizes audience and community participation as sources and channels for messages, was well suited for the cross-cultural application presented here.


Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/prevenção & controle , Redes Comunitárias , Promoção da Saúde/organização & administração , Programas de Rastreamento , Americanos Mexicanos , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Áreas de Pobreza , População Urbana , Neoplasias do Colo do Útero/etnologia , Neoplasias do Colo do Útero/prevenção & controle , Saúde da Mulher , Adulto , Barreiras de Comunicação , Redes Comunitárias/estatística & dados numéricos , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Mamografia/estatística & dados numéricos , Programas de Rastreamento/estatística & dados numéricos , Americanos Mexicanos/psicologia , Modelos Teóricos , Folhetos , Teste de Papanicolaou , Grupo Associado , Avaliação de Programas e Projetos de Saúde , Apoio Social , Texas/epidemiologia , Esfregaço Vaginal/estatística & dados numéricos
11.
Am J Hosp Pharm ; 32(8): 828-31, 1975 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1146841

RESUMO

The techniques of pharmacist-patient communication are discussed. Ways in which the pharmacist can identify the patient's information needs, control communication timing, define communication objectives, develop methods of communication and evaluate the effectiveness of his instructions are covered.


Assuntos
Comunicação , Pacientes , Educação Continuada em Farmácia , Humanos , Cooperação do Paciente , Farmacêuticos , Fatores de Tempo , Washington
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