RESUMEN
Indigenous youth in the United States are at high-risk for experiencing homelessness related to adverse childhood experiences such as parental substance use and low educational attainment. Such experiences may lead to adverse physical and mental health issues; these youth also have positive attributes of psychological capita (hope, self-efficacy, resilience, optimism) that are related to health outcomes. The purpose of this secondary analysis was to describe demographic attributes and psychological capital in Indigenous youth experiencing homelessness (IYEH) who participated in a longitudinal intervention study related to safe sex behaviors and life satisfaction. From a total of 602, Indigenous participants (n = 111; mean age 21.25 ± 1.82 years) were recruited from drop-in centers in Austin, Texas and Columbus, Ohio. Data were collected immediately after the intervention and at 3- and 6-month intervals. For this analysis, only data collected at the final time-point were used. Valid scales with Cronbach alphas of 0.75-0.92 (Hope, Resilience, Optimism, Self-efficacy for Substance Refusal, Self-efficacy for Safer Sex, Safe Sex Behaviors, Social Connectedness, and Life Satisfaction) were used. The majority of the IYEH reported smoking, drinking, and using drugs. Psychological capital variables of hope, self-efficacy for negotiating safer sex, resilience, and optimism were significantly related to one another, but not to safe sex behaviors or intention to use condoms. Resilience and optimism were significantly related to social connectedness but not to other psychological capital variables. Life satisfaction was significantly associated with hope, resilience, and optimism. Findings have implications for further theory and research development.
Asunto(s)
Esperanza , Satisfacción Personal , Factores Protectores , Resiliencia Psicológica , Autoeficacia , Humanos , Femenino , Masculino , Adulto Joven , Estudios Longitudinales , Jóvenes sin Hogar/psicología , Jóvenes sin Hogar/estadística & datos numéricos , Ohio , Sexo Seguro/psicología , Texas , Adolescente , Optimismo/psicología , Estados UnidosRESUMEN
Nurses working in rural acute and community-based settings are often asked for substance use treatment guidance and education in a health care system with minimal treatment services available. Nursing science provides an alternative answer for nurses to lean on in their clinical practice when working with rural-dwelling youth in the midst of substance misuse. Practical strategies are offered, which nurses may integrate into their routine clinical care to strengthen the nurse-patient relationship and enhance positive attributes among youth. Connective caring practice is essential to support rural youth well-being and recovery in the midst of substance misuse. [Journal of Psychosocial Nursing and Mental Health Services, 62(6), 7-11.].
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Relaciones Enfermero-Paciente , Trastornos Relacionados con Sustancias , Humanos , Trastornos Relacionados con Sustancias/psicología , Trastornos Relacionados con Sustancias/enfermería , Adolescente , Enfermería Psiquiátrica , Población Rural , Servicios de Salud RuralRESUMEN
People with intellectual and developmental disabilities (IDD) experience elevated risk for poor health and social outcomes in adulthood and are at risk for experiencing homelessness and housing instability. Although the exact prevalence of IDD among homeless populations is unknown, a small body of literature related to the intersection of IDD and homelessness suggests differential health needs and service use patterns, with a need for targeted health and social services. In this study, we explore the perceptions and experiences of 18 homeless or disability service providers about (a) their clients at the intersection of IDD and homelessness and (b) their role and the services provided at the intersection of IDD and homelessness. Participants struggled to provide appropriate, accessible services for this population, owing to lack of training and awareness of specific needs, fragmented systems, and inadequately funded healthcare and housing support. Our findings also reveal that clients at this intersection have high contact with public systems, which places them at risk for losing their right to self-determination. Recommendations center on systems transformation to facilitate the ability of providers to collaborate and to make data-driven decisions to deliver person-centered care.
Asunto(s)
Discapacidades del Desarrollo , Personas con Mala Vivienda , Niño , Humanos , Discapacidades del Desarrollo/epidemiología , Servicio Social , Atención a la Salud , ViviendaRESUMEN
Psychological capital (PsyCap) is a term coined in organizational psychology and refers to a person's development of states that motivate behavior. Also known in the literature as PsyCap, this construct typically refers to positive states of hope, self-efficacy, resilience, and optimism that are amenable to intervention and that are related to subjective well-being and life satisfaction. The aims of this systematic scoping review were to explore how PsyCap is described in youth mental health literature and how PsyCap and mental health are related. Results from four databases were reported following PRISMA guidelines. A total of 772 studies were identified and 16 studies were fully reviewed, including an overall sample of 6,772 youth from six countries. PsyCap has a positive relationship with mental health in youth. Future studies should involve school nurses to validate the constructs that characterize PsyCap and validate an instrument for measuring PsyCap in youth mental health in English.
Asunto(s)
Salud Mental , Resiliencia Psicológica , Humanos , Adolescente , Estudios Transversales , Estrés Psicológico/psicología , AutoeficaciaRESUMEN
Societal trends and COVID-19 quarantines have increased the number of adolescents experiencing social isolation, placing them at heightened risk for mental health issues. The aim of this review is to explore protective factors that might mitigate psychological harm in the presence of social isolation. A systematic literature review was conducted using Fink's step-by-step process. Four library databases were searched, and results were reported using PRISMA. Of the 246 studies reviewed, 12 studies were retained following the quality assessment. The sample includes 14,064 participants from USA, Australia, and Europe, ranging from 10-19 years old. Social connectedness (ie., family connectedness, school connectedness, social support), self-esteem, and prosocial behaviors were the most common protective factors to social isolation. Additional factors such as self-efficacy, optimism, and ethnic identity are discussed. Implications for future research are recommended, including the need to explore spiritual, biological, and sociocultural factors influencing social connectedness and mental health in adolescents.
Asunto(s)
COVID-19 , Salud Mental , Adolescente , Adulto , Altruismo , Niño , Humanos , SARS-CoV-2 , Aislamiento Social , Adulto JovenRESUMEN
School nurses represent cost-effective investments in students' health and educational success. Alternative high schools (AHSs) serve an understudied population of youth who are at risk for school dropout and face numerous social inequities, heightening their risk for poor health outcomes. In this two-phase explanatory sequential mixed methods study, we examined school nurse staffing in Texas AHSs. Findings suggest Texas AHSs face understaffing for familiar reasons common across districts (e.g., lack of funding), but also reveal potential deeper inequities. Quantitative findings indicate 71% of Texas AHSs have some form of nursing support, most often an on-call or part-time nurse. Qualitative findings support and enrich this finding with insights into the negative consequences of not having a full-time nurse, indiscriminate approaches to staffing AHSs, and how AHSs can be the only school in the district without a full-time nurse. Altogether, our findings reveal opportunities to better support AHSs with adequate nursing support.
RESUMEN
BACKGROUND: Social determinants of health affect health behaviors and outcomes. Youth experiencing homelessness suffer significant deprivation of resources such as inadequate housing, reduced education, poor health care, and decreased economic stability. Inner resources, such as psychological capital, may also be related to health behaviors and health outcomes. OBJECTIVE: In this study, we sought to describe and explore associations among selected determinants of health and self-reported scores on indicators of psychological capital among youth experiencing homelessness. METHODS: This cross-sectional secondary analysis was conducted with a randomized subsample of 148 youth. We calculated chi-square frequencies to describe the data, classical item analyses to evaluate responses, and correlation tests to examine significance of associations. RESULTS: Youth in this sample demonstrated that they possess inner resources associated with determinants of health. Education, health care, and social support were significantly associated with attributes of psychological capital (hope, efficacy, resilience, optimism). Sexual minority groups had high representation in this subsample (25.7%), indicating a need for more study and equitable services for this population. CONCLUSION: More research should be conducted to better understand the associations between determinants of health, psychological capital, and health behaviors among disadvantaged youth to advance health equity initiatives.
Asunto(s)
Jóvenes sin Hogar , Determinantes Sociales de la Salud , Humanos , Determinantes Sociales de la Salud/estadística & datos numéricos , Femenino , Estudios Transversales , Masculino , Adolescente , Jóvenes sin Hogar/psicología , Jóvenes sin Hogar/estadística & datos numéricos , Apoyo Social , Encuestas y Cuestionarios , Conductas Relacionadas con la Salud , Resiliencia Psicológica , AutoinformeRESUMEN
BACKGROUND: A sizeable body of data demonstrates that membrane ICAM-1 (mICAM-1) plays a significant role in host defense in a site-specific fashion. On the pulmonary vascular endothelium, mICAM-1 is necessary for normal leukocyte recruitment during acute inflammation. On alveolar epithelial cells (AECs), we have shown previously that the presence of normal mICAM-1 is essential for optimal alveolar macrophage (AM) function. We have also shown that ICAM-1 is present in the alveolar space as a soluble protein that is likely produced through cleavage of mICAM-1. Soluble intercellular adhesion molecule-1 (sICAM-1) is abundantly present in the alveolar lining fluid of the normal lung and could be generated by proteolytic cleavage of mICAM-1, which is highly expressed on type I AECs. Although a growing body of data suggesting that intravascular sICAM-1 has functional effects, little is known about sICAM-1 in the alveolus. We hypothesized that sICAM-1 in the alveolar space modulates the innate immune response and alters the response to pulmonary infection. METHODS: Using the surfactant protein C (SPC) promoter, we developed a transgenic mouse (SPC-sICAM-1) that constitutively overexpresses sICAM-1 in the distal lung, and compared the responses of wild-type and SPC-sICAM-1 mice following intranasal inoculation with K. pneumoniae. RESULTS: SPC-sICAM-1 mice demonstrated increased mortality and increased systemic dissemination of organisms compared with wild-type mice. We also found that inflammatory responses were significantly increased in SPC-sICAM-1 mice compared with wild-type mice but there were no difference in lung CFU between groups. CONCLUSIONS: We conclude that alveolar sICAM-1 modulates pulmonary inflammation. Manipulating ICAM-1 interactions therapeutically may modulate the host response to Gram negative pulmonary infections.
Asunto(s)
Acrilamidas/metabolismo , Células Epiteliales/inmunología , Inmunidad Innata , Infecciones por Klebsiella/inmunología , Klebsiella pneumoniae/patogenicidad , Neumonía Bacteriana/inmunología , Alveolos Pulmonares/inmunología , beta-Alanina/análogos & derivados , Animales , Células Cultivadas , Quimiocina CXCL2/metabolismo , Quimiotaxis , Modelos Animales de Enfermedad , Células Epiteliales/microbiología , Mediadores de Inflamación/metabolismo , Infecciones por Klebsiella/genética , Infecciones por Klebsiella/microbiología , Macrófagos Alveolares/inmunología , Macrófagos Alveolares/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fagocitosis , Neumonía Bacteriana/genética , Neumonía Bacteriana/microbiología , Regiones Promotoras Genéticas , Alveolos Pulmonares/microbiología , Proteína C Asociada a Surfactante Pulmonar/genética , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba , beta-Alanina/genética , beta-Alanina/metabolismoRESUMEN
Pneumocystis pneumonia (PCP), the most common opportunistic pulmonary infection associated with HIV infection, is marked by impaired gas exchange and significant hypoxemia. Immune reconstitution disease (IRD) represents a syndrome of paradoxical respiratory failure in patients with active or recently treated PCP subjected to immune reconstitution. To model IRD, C57BL/6 mice were selectively depleted of CD4(+) T cells using mAb GK1.5. Following inoculation with Pneumocystis murina cysts, infection was allowed to progress for 2 wk, GK1.5 was withdrawn, and mice were followed for another 2 or 4 wk. Flow cytometry of spleen cells demonstrated recovery of CD4(+) cells to >65% of nondepleted controls. Lung tissue and bronchoalveolar lavage fluid harvested from IRD mice were analyzed in tandem with samples from CD4-depleted mice that manifested progressive PCP for 6 wks. Despite significantly decreased pathogen burdens, IRD mice had persistent parenchymal lung inflammation, increased bronchoalveolar lavage fluid cellularity, markedly impaired surfactant biophysical function, and decreased amounts of surfactant phospholipid and surfactant protein (SP)-B. Paradoxically, IRD mice also had substantial increases in the lung collectin SP-D, including significant amounts of an S-nitrosylated form. By native PAGE, formation of S-nitrosylated SP-D in vivo resulted in disruption of SP-D multimers. Bronchoalveolar lavage fluid from IRD mice selectively enhanced macrophage chemotaxis in vitro, an effect that was blocked by ascorbate treatment. We conclude that while PCP impairs pulmonary function and produces abnormalities in surfactant components and biophysics, these responses are exacerbated by IRD. This worsening of pulmonary inflammation, in response to persistent Pneumocystis Ags, is mediated by recruitment of effector cells modulated by S-nitrosylated SP-D.
Asunto(s)
Síndrome Inflamatorio de Reconstitución Inmune/inmunología , Neumonía por Pneumocystis/inmunología , Proteína D Asociada a Surfactante Pulmonar/metabolismo , Animales , Western Blotting , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/inmunología , Linfocitos T CD4-Positivos/inmunología , Electroforesis en Gel de Poliacrilamida , Citometría de Flujo , Síndrome Inflamatorio de Reconstitución Inmune/complicaciones , Síndrome Inflamatorio de Reconstitución Inmune/metabolismo , Pulmón/inmunología , Pulmón/microbiología , Pulmón/patología , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Neumonía por Pneumocystis/complicaciones , Neumonía por Pneumocystis/metabolismo , Proteína B Asociada a Surfactante Pulmonar/inmunología , Proteína B Asociada a Surfactante Pulmonar/metabolismo , Proteína D Asociada a Surfactante Pulmonar/inmunología , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Pneumocystis infections increase host susceptibility to additional insults that would be tolerated in the absence of infection, such as hyperoxia. In an in vivo model using CD4-depleted mice, we previously demonstrated that Pneumocystis murina pneumonia causes significant mortality following an otherwise nonlethal hyperoxic insult. Infected mice demonstrated increased pulmonary inflammation and alveolar epithelial cell apoptosis compared to controls. To test the mechanisms underlying these observations, we examined expression of components of the Fas-Fas ligand pathway in P. murina-infected mice exposed to hyperoxia. Hyperoxia alone increased expression of Fas on the surface of type II alveolar epithelial cells; conversely, infection with P. murina led to increased lung expression of Fas ligand. We hypothesized that inhibition of inflammatory responses or direct inhibition of alveolar epithelial cell apoptosis would improve survival in P. murina-infected mice exposed to hyperoxia. Mice were depleted of CD4(+) T cells and infected with P. murina and then were exposed to >95% oxygen for 4 days, followed by return to normoxia. Experimental groups received vehicle, dexamethasone, or granulocyte-macrophage colony-stimulating factor (GM-CSF). Compared with the vehicle-treated group, treatment with dexamethasone reduced Fas ligand expression and significantly improved survival. Similarly, treatment with GM-CSF, an agent we have shown protects alveolar epithelial cells against apoptosis, decreased Fas ligand expression and also improved survival. Our results suggest that the dual stresses of P. murina infection and hyperoxia induce lung injury via activation of the Fas-Fas ligand pathway and that corticosteroids and GM-CSF reduce mortality in P. murina-infected mice exposed to hyperoxic stress by inhibition of inflammation and apoptosis.
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Lesión Pulmonar Aguda/inmunología , Apoptosis/inmunología , Hiperoxia/inmunología , Inflamación/inmunología , Neumonía por Pneumocystis/inmunología , Lesión Pulmonar Aguda/etiología , Lesión Pulmonar Aguda/patología , Animales , Antiinflamatorios/farmacología , Apoptosis/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Dexametasona/farmacología , Proteína Ligando Fas/efectos de los fármacos , Proteína Ligando Fas/inmunología , Proteína Ligando Fas/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Hiperoxia/complicaciones , Hiperoxia/patología , Inmunohistoquímica , Inflamación/patología , Ratones , Ratones Endogámicos C57BL , Neumonía/complicaciones , Neumonía/inmunología , Neumonía/patología , Neumonía por Pneumocystis/complicaciones , Neumonía por Pneumocystis/patología , Alveolos Pulmonares/inmunología , Alveolos Pulmonares/metabolismo , Transducción de Señal/inmunología , Receptor fas/efectos de los fármacos , Receptor fas/inmunología , Receptor fas/metabolismoRESUMEN
Chronic obstructive pulmonary disease (COPD) is characterized by the presence of airflow obstruction and lung destruction with airspace enlargement. In addition to cigarette smoking, respiratory pathogens play a role in pathogenesis, but specific organisms are not always identified. Recent reports demonstrate associations between the detection of Pneumocystis jirovecii DNA in lung specimens or respiratory secretions and the presence of emphysema in COPD patients. Additionally, human immunodeficiency virus-infected individuals who smoke cigarettes develop early emphysema, but a role for P. jirovecii in pathogenesis remains speculative. We developed a new experimental model using immunocompetent mice to test the interaction of cigarette smoke exposure and environmentally acquired Pneumocystis murina infection in vivo. We hypothesized that cigarette smoke and P. murina would interact to cause increases in total lung capacity, airspace enlargement, and pulmonary inflammation. We found that exposure to cigarette smoke significantly increases the lung organism burden of P. murina. Pulmonary infection with P. murina, combined with cigarette smoke exposure, results in changes in pulmonary function and airspace enlargement characteristic of pulmonary emphysema. P. murina and cigarette smoke exposure interact to cause increased lung inflammatory cell accumulation. These findings establish a novel animal model system to explore the role of Pneumocystis species in the pathogenesis of COPD.
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Enfisema/inducido químicamente , Enfisema/microbiología , Pulmón/microbiología , Pulmón/patología , Pneumocystis/crecimiento & desarrollo , Neumonía/inducido químicamente , Neumonía/microbiología , Humo , Animales , Líquido del Lavado Bronquioalveolar/citología , Recuento de Colonia Microbiana , Enfisema/complicaciones , Capacidad Residual Funcional , Recuento de Linfocitos , Subgrupos Linfocitarios/inmunología , Ratones , Ratones Endogámicos C57BL , Capacidad Pulmonar TotalRESUMEN
Patients with Pneumocystis pneumonia often develop respiratory failure after entry into medical care, and one mechanism for this deterioration may be increased alveolar epithelial cell injury. In vitro, we previously demonstrated that Pneumocystis is not cytotoxic for alveolar epithelial cells. In vivo, however, infection with Pneumocystis could increase susceptibility to injury by stressors that, alone, would be sublethal. We examined transient exposure to hyperoxia as a prototypical stress that does cause mortality in normal mice. Mice were depleted of CD4+ T cells and inoculated intratracheally with Pneumocystis. Control mice were depleted of CD4+ T cells but did not receive Pneumocystis. After 4 weeks, mice were maintained in normoxia, were exposed to hyperoxia for 4 days, or were exposed to hyperoxia for 4 days followed by return to normoxia. CD4-depleted mice with Pneumocystis pneumonia demonstrated significant mortality after transient exposure to hyperoxia, while all uninfected control mice survived this stress. We determined that organism burdens were not different. However, infected mice exposed to hyperoxia and then returned to normoxia demonstrated significant increases in inflammatory cell accumulation and lung cell apoptosis. We conclude that Pneumocystis pneumonia leads to increased mortality following a normally sublethal hyperoxic insult, accompanied by alveolar epithelial cell injury and increased pulmonary inflammation.
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Hiperoxia/complicaciones , Neumonía por Pneumocystis/complicaciones , Animales , Apoptosis , Linfocitos T CD4-Positivos/inmunología , Modelos Animales de Enfermedad , Humanos , Hiperoxia/inmunología , Hiperoxia/patología , Inflamación/patología , Lesión Pulmonar , Depleción Linfocítica , Macrófagos Alveolares/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Fagocitosis , Pneumocystis/inmunología , Neumonía por Pneumocystis/inmunología , Neumonía por Pneumocystis/patologíaRESUMEN
Loss of T cell number and function during HIV infection or secondary to pharmacologic immunosuppression renders individuals susceptible to opportunistic infections, including Pneumocystis carinii pneumonia. Because costimulatory receptors are critical for optimal T cell function, we hypothesized that these proteins would regulate susceptibility to opportunistic infections. We found that despite normal T cell numbers, mice deficient in the costimulatory molecules CD2 and CD28 spontaneously developed P. carinii pneumonia. In experiments using intratracheal injection of P. carinii organisms to induce infection, the loss of CD28 alone was sufficient to render mice susceptible to acute infection; however, the organism was eventually cleared. Examination of inflammatory responses to P. carinii revealed that mice deficient in both CD2 and CD28 accumulated CD8(+) T cells in their lungs in response to infection and demonstrated markedly reduced specific Ab titers. Analysis of cytokine profiles suggested that regulation of IL-10 and IL-15 may be important elements of the response to this pathogen. Thus, costimulatory molecule function is critical in determining the initial susceptibility to infection with P. carinii. Analysis of immunologic responses in these mice may provide important insights into the defects that render individuals susceptible to opportunistic infection, and provide opportunities for novel immunologically based therapies.
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Antígenos CD2/fisiología , Antígenos CD28/fisiología , Pneumocystis/inmunología , Neumonía por Pneumocystis/inmunología , Animales , Anticuerpos Antifúngicos/biosíntesis , Especificidad de Anticuerpos/genética , Antígenos CD2/genética , Antígenos CD28/genética , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Movimiento Celular/genética , Movimiento Celular/inmunología , Citocinas/biosíntesis , Citocinas/genética , Susceptibilidad a Enfermedades/inmunología , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Inmunidad Innata/genética , Estudios Longitudinales , Pulmón/inmunología , Pulmón/metabolismo , Linfocitosis/genética , Linfocitosis/inmunología , Linfocitosis/microbiología , Linfocitosis/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones SCID , Neumonía por Pneumocystis/genética , Neumonía por Pneumocystis/microbiología , Alveolos Pulmonares/inmunología , Alveolos Pulmonares/microbiología , Alveolos Pulmonares/patologíaRESUMEN
Surfactant protein A (SP-A), a member of the collectin family, selectively binds to Pneumocystis carinii and mediates interactions between pathogen and host alveolar macrophages in vitro. To test the hypothesis that mice lacking SP-A have delayed clearance of Pneumocystis organisms and enhanced lung injury, wild-type C57BL/6 (WT) and SP-A-deficient mice (SP-A(-/-)) with or without selective CD4(+)-T-cell depletion were intratracheally inoculated with Pneumocystis organisms. Four weeks later, CD4-depleted SP-A-deficient mice had developed a more severe Pneumocystis infection than CD4-depleted WT (P. carinii pneumonia [PCP] scores of 3 versus 2, respectively). Whereas all non-CD4-depleted WT mice were free of PCP, intact SP-A(-/-) mice also had evidence of increased organism burden. Pneumocystis infection in SP-A-deficient mice was associated histologically with enhanced peribronchial and/or perivascular cellularity (score of 4 versus 2, SP-A(-/-) versus C57BL/6 mice, respectively) and a corresponding increase in bronchoalveolar lavage (BAL) cell counts. Increases in SP-D content, gamma interferon, interleukin-4, interleukin-5, and tumor necrosis factor alpha in BAL fluid occurred but were attenuated in PCP-infected SP-A(-/-) mice compared to WT mice. There were increases in total BAL NO levels in both infected groups, but nitrite levels were higher in SP-A(-/-) mice, indicating a reduction in production of higher oxides of nitrogen that was also reflected in lower levels of 3-nitrotyrosine staining in the SP-A(-/-) group. We conclude that despite increases in inflammatory cells, SP-A-deficient mice infected with P. carinii exhibit an enhanced susceptibility to the organism and attenuated production of proinflammatory cytokines and reactive oxygen-nitrogen species. These data support the concept that SP-A is a local effector molecule in the lung host defense against P. carinii in vivo.
Asunto(s)
Citocinas/metabolismo , Pulmón/microbiología , Pulmón/patología , Pneumocystis carinii/fisiología , Proteína A Asociada a Surfactante Pulmonar/deficiencia , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Tirosina/análogos & derivados , Animales , Líquido del Lavado Bronquioalveolar/química , Humanos , Inflamación/complicaciones , Inflamación/metabolismo , Inflamación/microbiología , Inflamación/patología , Pulmón/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Óxido Nítrico/metabolismo , Infecciones por Pneumocystis/inmunología , Infecciones por Pneumocystis/metabolismo , Infecciones por Pneumocystis/microbiología , Infecciones por Pneumocystis/patología , Proteína A Asociada a Surfactante Pulmonar/genética , Proteína D Asociada a Surfactante Pulmonar/metabolismo , Tirosina/metabolismoRESUMEN
Surfactant protein-D (SP-D), a member of the "collectin" family, has been shown to play a role in innate immunity through modulation of inflammation and clearance of organisms. The role of SP-D in host defense against Pneumocystis carinii pneumonia was assessed using SP-D knockout (KO) mice. When inoculated with P. carinii, both wild-type (wt) and SP-D KO mice required CD4 cell depletion to develop infection. In CD4 cell-depleted models, 2 weeks after infection with P. carinii, SP-D KO mice developed increased intensity of infection, compared with wt mice, despite higher lung-inflammation scores and increased amounts of alveolar inflammatory cells. The increased inflammation seen in SP-D KO mice was accompanied by increases in lung weight, expression of inducible nitric oxide (NO) synthase, total NO levels, and 3-nitrotyrosine levels in lung tissue. These results indicate that SP-D plays a role in host defense against P. carinii in vivo by modulating clearance of organisms, lung inflammation, and metabolism of NO.