Administration of intrapulmonary sodium polyacrylate to induce lung injury for the development of a porcine model of early acute respiratory distress syndrome.

BACKGROUND: The loss of alveolar epithelial and endothelial integrity is a central component in acute respiratory distress syndrome (ARDS); however, experimental models investigating the mechanisms of epithelial injury are lacking. The purpose of the present study was to design and develop an experimental porcine model of ARDS by inducing lung injury with intrapulmonary administration of sodium polyacrylate (SPA). METHODS: The present study was performed at the Centre for Comparative Medicine, University of British Columbia, Vancouver, British Columbia. Human alveolar epithelial cells were cultured with several different concentrations of SPA; a bioluminescence technique was used to assess cell death associated with each concentration. In the anesthetized pig model (female Yorkshire X pigs (n = 14)), lung injury was caused in 11 animals (SPA group) by injecting sequential aliquots (5 mL) of 1% SPA gel in aqueous solution into the distal airway via a rubber catheter through an endotracheal tube. The SPA was dispersed throughout the lungs by manual bag ventilation. Three control animals (CON group) underwent all experimental procedures and measurements with the exception of SPA administration. RESULTS: The mean (± SD) ATP concentration after incubation of human alveolar epithelial cells with 0.1% SPA (0.92 ± 0.27 μM/well) was approximately 15% of the value found for the background control (6.30 ± 0.37 μM/well; p < 0.001). Elastance of the respiratory system (E RS) and the lung (E L) increased in SPA-treated animals after injury (p = 0.003 and p < 0.001, respectively). Chest wall elastance (E CW) did not change in SPA-treated animals. There were no differences in E RS, E L, or E CW in the CON group when pre- and post-injury values were compared. Analysis of bronchoalveolar lavage fluid showed a significant shift toward neutrophil predominance from before to after injury in SPA-treated animals (p < 0.001) but not in the CON group (p = 0.38). Necropsy revealed marked consolidation and congestion of the dorsal lung lobes in SPA-treated animals, with light-microscopy evidence of bronchiolar and alveolar spaces filled with neutrophilic infiltrate, proteinaceous debris, and fibrin deposition. These findings were absent in animals in the CON group. Electron microscopy of lung tissue from SPA-treated animals revealed injury to the alveolar epithelium and basement membranes, including intra-alveolar neutrophils and fibrin on the alveolar surface and intravascular fibrin (microthrombosis). CONCLUSIONS: In this particular porcine model, the nonimmunogenic polymer SPA caused a rapid exudative lung injury. This model may be useful to study ARDS caused by epithelial injury and inflammation

American palm ethnomedicine: A meta-analysis

<p>Abstract</p> <p>Background</p> <p>Many recent papers have documented the phytochemical and pharmacological bases for the use of palms (<it>Arecaceae</it>) in ethnomedicine. Early publications were based almost entirely on interviews that solicited local knowledge. More recently, ethnobotanically guided searches for new medicinal plants have proven more successful than random sampling for identifying plants that contain biodynamic ingredients. However, limited laboratory time and the high cost of clinical trials make it difficult to test all potential medicinal plants in the search for new drug candidates. The purpose of this study was to summarize and analyze previous studies on the medicinal uses of American palms in order to narrow down the search for new palm-derived medicines.</p> <p>Methods</p> <p>Relevant literature was surveyed and data was extracted and organized into medicinal use categories. We focused on more recent literature than that considered in a review published 25 years ago. We included phytochemical and pharmacological research that explored the importance of American palms in ethnomedicine.</p> <p>Results</p> <p>Of 730 species of American palms, we found evidence that 106 species had known medicinal uses, ranging from treatments for diabetes and leishmaniasis to prostatic hyperplasia. Thus, the number of American palm species with known uses had increased from 48 to 106 over the last quarter of a century. Furthermore, the pharmacological bases for many of the effects are now understood.</p> <p>Conclusions</p> <p>Palms are important in American ethnomedicine. Some, like <it>Serenoa repens </it>and <it>Roystonea regia</it>, are the sources of drugs that have been approved for medicinal uses. In contrast, recent ethnopharmacological studies suggested that many of the reported uses of several other palms do not appear to have a strong physiological basis. This study has provided a useful assessment of the ethnobotanical and pharmacological data available on palms.</p

Astrocitoma subependimário de células gigantes em pacientes com esclerose tuberosa: achados em ressonância magnética de dez casos Subependymal giant cell astrocytoma in patients with tuberous sclerosis: magnetic resonance imaging findings in ten cases

OBJETIVO: Relatar os achados de ressonância magnética (RM) em 10 casos de astrocitoma subependimário de células gigantes (ASCG) em pacientes com esclerose tuberosa (ET). MÉTODO: Foram estudados de forma retrospectiva 10 pacientes com ET e diagnóstico histológico comprovado de ASCG. Quatro pacientes eram do sexo masculino e seis do feminino, com idade média de 15,7 anos. Todos os pacientes foram investigados com RM, sendo os exames revisados por dois radiologistas, havendo decisão por consenso sobre os achados de imagem. Foram analisados os seguintes achados: localização, dimensões, intensidade de sinal em T1/T2, realce pós-contraste e outros achados associados. RESULTADOS: Todos os pacientes apresentaram lesão única sugestiva de ASCG, medindo entre 1,5 cm e 8 cm em seu maior diâmetro. Oito lesões foram encontradas junto ao forame de Monro (80%) e duas adjacentes ao corpo do ventrículo lateral (20%). Os tumores apresentavam nas imagens pesadas em T1 médio sinal (70%) e em T2 alto sinal (100%), com realce intenso após a administração do gadolínio (100%). CONCLUSÃO: Os astrocitomas subependimários de células gigantes em pacientes com ET em geral apresentam-se como lesão única próxima ao forame de Monro, com médio sinal nas imagens ponderadas em T1, alto sinal em T2 e realce intenso após a administração de contraste.<br>OBJECTIVE: To report the magnetic resonance imaging (MRI) findings in 10 patients with subependimal giant cell astrocytoma (SGCA) and tuberous sclerosis (TS). METHOD: Ten patients were retrospectively studied, presenting TS and histologically proven SGCA. Four patients were male and six female, with mean age 15.7 years. All patients underwent MRI, which was analyzed by two radiologists, final diagnosis was reached by consensus. The following findings were studied: topography, size, signal intensity on T1/T2-weighted images, contrast enhancement and associated findings. RESULTS: All patients presented a single lesion suggestive of SGCA, measuring between 1.5 cm and e 8 cm in the largest diameter. Eight lesions were found near the foramen of Monro and two in the body of the lateral ventricles. The tumors showed preferentially intermediate signal on T1 (70%), high signal on T2-weighted images (100%), with intense enhancement after contrast administration (100%). CONCLUSION: SGCA in patients with TS usually presents as a single lesion near the foramen of Monro, with intermediate signal on T1, high signal on T2-weighted images and intense contrast enhancement

Meduloblastoma em adultos: análise de uma casuística e resultados cirúrgicos Medulloblastoma in adulthood: analysis of a casuistics and surgical results

Analisamos 15 casos de meduloblastoma em adultos (8 homens e 7 mulheres), com idade média de 23,7 anos (variação de 13 a 46) submetidos a ressecção cirúrgica no período de fevereiro de 1988 a outubro de 1995. Os tumores se localizavam no hemisfério cerebelar em 7 casos (1 com extensão supratentorial e outro atingindo a cisterna do ângulo pontocerebelar), no vermis e hemisférico em 4 e apenas no vermis em outros 4. A ressecção foi considerada radical em 7 casos, subtotal em 7 e parcial em um. Não houve mortalidade operatória. Aspectos relativos ao comportamento biológico e prognóstico são discutidos.<br>We report on 15 cases of medulloblastoma of adult onset (8 male and 7 female) operated upon posterior fossa approach from February 1988 to October 1995. Tumors were localized in cerebellar hemisphere in 7 cases (one with extension to supratentorial notch and another case reaching the cerebello-pontine angle cistern), in vermis and hemisphere in four, only in vermis in another four. Resection was total in seven patients, subtotal in other seven, and partial in one.There was no operative mortality. Aspects regarding biological behavior, diagnosis, pathological findings, surgery and survival are discussed as well as prognostic factors

Biomarkers of chemotaxis and inflammation in cerebrospinal fluid and serum in individuals with HIV-1 subtype C versus B

A defective chemokine motif in the HIV-1 Tat protein has been hypothesized to alter central nervous system cellular trafficking and inflammation, rendering HIV-1 subtype C less neuropathogenic than B. To evaluate this hypothesis, we compared biomarkers of cellular chemotaxis and inflammation in cerebrospinal fluid (CSF) and serum in individuals infected with HIV-1 subtypes B (n=27) and C (n=25) from Curitiba, Brazil. None had opportunistic infections. Chemokines (MCP-1, MIP-1α, MIP-1β, RANTES, IP-10) and cytokines (TNF-α, IFN-y, IL-1β, IL-2, IL-4, IL-6, IL-7, IL-10) were measured using the multiplex bead suspension array immunoassays or ELISA HD. CSF and serum biomarker concentrations were compared between subtype B and C groups and HIV-positive and HIV-negative subjects (N=19) using an independent group t-test (unadjusted analysis) and linear regression (adjusted analysis), controlling for nadir CD4 and CSF and plasma HIV RNA suppression. CSF levels of cytokines and chemokines were significantly (p< 0.05) elevated in HIV-positive versus HIV-negative participants for 7/13 biomarkers measured, but levels did not differ for subtypes B and C. Serum levels were significantly elevated for 4/13 markers, with no significant differences between subtypes B and C. Although pleocytosis was much more frequent in HIV-positive than in HIV-negative individuals (27% vs. 0%), subtypes B and C did not differ (32% and 22%; p = 0.23). We did not find molecular evidence to support the hypothesis that intrathecal chemotaxis and inflammation is less in HIV-1 subtype C than in subtype B. Biomarker changes in CSF were more robust than in serum, suggesting compartmentalization of the immunological response to HIV