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Sporotrichosis is caused by species of fungi within the Sporothrix schenckii complex that infect man and animals. In Rio de Janeiro, Brazil, an epidemic has been observed since 1998, with most of the cases being related to transmission from infected cats. Although the definitive diagnosis of feline sporotrichosis is made by fungal culture, cytopathological and histopathological examinations are used routinely, because the long culture period may delay treatment onset. However, alternative methods are desirable in cases of low fungal burden. Immunohistochemistry (IHC) has been described as a sensitive method for diagnosing human and canine sporotrichosis, but there are no reports of its application to cats. The aim of this study was to analyse the sensitivity of cytopathological examination (Quick Panoptic method), histopathology (Grocott silver stain) and anti-Sporothrix IHC by blinded comparisons, using fungal culture as the reference standard. Samples were collected from 184 cats with sporotrichosis that exhibited skin ulcers. The sensitivities of Grocott silver stain, cytopathological examination and IHC were 91.3%, 87.0% and 88.6%, respectively. Grocott silver stain showed the best performance. IHC showed high sensitivity, as did cytopathological examination and these may be considered as alternative methodologies. When the three methods were combined, the diagnosis was established in 180 (97.8%) out of 184 cases. Taken together, these findings indicate the need to implement these methods as routine tools for the early diagnosis of sporotrichosis in cats, notably when fungal culture is not available.
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Doenças do Gato/diagnóstico , Esporotricose/veterinária , Animais , Gatos , Citodiagnóstico/métodos , Diagnóstico Precoce , Imuno-Histoquímica/métodos , Sensibilidade e Especificidade , Coloração e Rotulagem/métodosRESUMO
OBJECTIVES: The aim of this study was to analyse the expression and function of nucleotide-binding oligomerization domain (NOD)1 and NOD2 in isolated cells of patients with rheumatoid arthritis (RA). METHOD: mRNA expression levels of NOD1, NOD2, and receptor-interacting serine/threonine kinase 2 (RIPK2) genes were determined by quantitative polymerase chain reaction (qPCR) in peripheral blood mononuclear cells (PBMCs) and synovial fluid T cells (SFTCs) isolated from RA and osteoarthritis (OA) patients. Cytokines were measured by enzyme-linked immunosorbent assay (ELISA) in plasma and cell culture supernatants. The stimulatory effect of RA SF was assessed by an in-vitro NOD2 activation assay using nuclear factor kappa B (NF-κB) luciferase-transfected cells. RESULTS: A significantly higher level of NOD2 and RIPK2 mRNA expression, but not NOD1, was observed on PBMCs and SFTCs isolated from RA patients compared to the OA control group. In addition, the NOD2 pathway up-regulation was functional, as stimulation of PBMCs with muramyl dipeptide (MDP) induced the production of higher amounts of tumour necrosis factor (TNF)-α, interleukin (IL)-8, and IL-1ß compared with OA PBMCs. Incubation of PBMCs from healthy donors with recombinant TNF-α or RA serum induced the expression of NOD2 mRNA. Finally, SF isolated from RA patients is able to activate the NF-κB signalling pathway in HEK293T-transfected cells in a NOD2-dependent manner. CONCLUSIONS: Our findings suggest that NOD2/RIPK2 signalling is up-regulated in immune cells of RA patients. Moreover, it seems that there is a NOD2 agonist in the SF of RA patients. Therefore, NOD2/RIPK2 activation can modulate the innate immune response and may play a role in the perpetuation of the inflammatory response in RA.
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There is growing evidence that the commensal bacteria in the gastrointestinal tract (the gut microbiota) influence the development of autoimmunity in rodent models. Since humans have co-evolved with commensals for millennia, it is likely that people, who are genetically predisposed to autoimmunity, harbor gut microbial communities that similarly influence the onset and/or severity of disease. Beyond the current efforts to identify such disease-promoting or -preventing commensals ("pathobionts" or "symbionts"), it will be important to determine what factors modulate them. Dietary changes are known to affect both the composition and function of the gut microbial communities, which in turn can alter the innate and adaptive immune system. In this review, we focus on the relationships between diet, microbiota, and autoimmune diseases. We hypothesize that the beneficial and life-prolonging effects of caloric restriction on a variety of autoimmune models including lupus might partly be mediated by its effects on the gut microbiome and associated virome, the collection of all viruses in the gut. We give recent examples of the immunomodulatory potential of select gut commensals and their products or diet-derived metabolites in murine models of arthritis, multiple sclerosis, and type 1 diabetes. Lastly, we summarize the published phenotypes of germ-free mouse models of lupus and speculate on any role of the diet-sensitive microbiome and virome in systemic lupus and the related antiphospholipid syndrome.
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Síndrome Antifosfolipídica/etiologia , Autoimunidade , Dieta/efeitos adversos , Lúpus Eritematoso Sistêmico/etiologia , Microbiota , Animais , Síndrome Antifosfolipídica/imunologia , Síndrome Antifosfolipídica/microbiologia , Síndrome Antifosfolipídica/terapia , Síndrome Antifosfolipídica/virologia , Restrição Calórica , Modelos Animais de Doenças , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/virologia , Interações Hospedeiro-Patógeno , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/microbiologia , Lúpus Eritematoso Sistêmico/terapia , Lúpus Eritematoso Sistêmico/virologia , Camundongos , Medição de Risco , Fatores de RiscoRESUMO
Nanostructuring boron-doped diamond (BDD) films increases their sensitivity and performance when used as electrodes in electrochemical environments. We have developed a method to produce such nanostructured, porous electrodes by depositing BDD thin film onto a densely packed "forest" of vertically aligned multiwalled carbon nanotubes (CNTs). The CNTs had previously been exposed to a suspension of nanodiamond in methanol causing them to clump together into "teepee" or "honeycomb" structures. These nanostructured CNT/BDD composite electrodes have been extensively characterized by scanning electron microscopy, Raman spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Not only do these electrodes possess the excellent, well-known characteristics associated with BDD (large potential window, chemical inertness, low background levels), but also they have electroactive areas and double-layer capacitance values â¼450 times greater than those for the equivalent flat BDD electrodes.
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OBJECTIVE: To compare general and disease-based modeling for fluid resuscitation and vasopressor use in intensive care units. METHODS: Retrospective cohort study involving 2944 adult medical and surgical intensive care unit (ICU) patients receiving fluid resuscitation. Within this cohort there were two disease-based groups, 802 patients with a diagnosis of pneumonia, and 143 patients with a diagnosis of pancreatitis. Fluid resuscitation either progressing to subsequent vasopressor administration or not was used as the primary outcome variable to compare general and disease-based modeling. RESULTS: Patients with pancreatitis, pneumonia and the general group all shared three common predictive features as core variables, arterial base excess, lactic acid and platelets. Patients with pneumonia also had non-invasive systolic blood pressure and white blood cells added to the core model, and pancreatitis patients additionally had temperature. Disease-based models had significantly higher values of AUC (p <â 0.05) than the general group (0.82 ± 0.02 for pneumonia and 0.83 ± 0.03 for pancreatitis vs. 0.79 ± 0.02 for general patients). CONCLUSIONS: Disease-based predictive modeling reveals a different set of predictive variables compared to general modeling and improved performance. Our findings add support to the growing body of evidence advantaging disease specific predictive modeling.
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Simulação por Computador , Sistemas de Apoio a Decisões Clínicas , Técnicas de Apoio para a Decisão , Hidratação/métodos , Unidades de Terapia Intensiva , Pancreatite/terapia , Pneumonia/terapia , Desequilíbrio Ácido-Base/fisiopatologia , Desequilíbrio Ácido-Base/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Estudos de Coortes , Feminino , Mortalidade Hospitalar , Humanos , Ácido Láctico/sangue , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Pancreatite/mortalidade , Pancreatite/fisiopatologia , Contagem de Plaquetas , Pneumonia/mortalidade , Pneumonia/fisiopatologia , Estudos Retrospectivos , Vasoconstritores/uso terapêuticoRESUMO
OBJECTIVES: To reduce unnecessary lab testing by predicting when a proposed future lab test is likely to contribute information gain and thereby influence clinical management in patients with gastrointestinal bleeding. Recent studies have demonstrated that frequent laboratory testing does not necessarily relate to better outcomes. DESIGN: Data preprocessing, feature selection, and classification were performed and an artificial intelligence tool, fuzzy modeling, was used to identify lab tests that do not contribute an information gain. There were 11 input variables in total. Ten of these were derived from bedside monitor trends heart rate, oxygen saturation, respiratory rate, temperature, blood pressure, and urine collections, as well as infusion products and transfusions. The final input variable was a previous value from one of the eight lab tests being predicted: calcium, PTT, hematocrit, fibrinogen, lactate, platelets, INR and hemoglobin. The outcome for each test was a binary framework defining whether a test result contributed information gain or not. PATIENTS: Predictive modeling was applied to recognize unnecessary lab tests in a real world ICU database extract comprising 746 patients with gastrointestinal bleeding. MAIN RESULTS: Classification accuracy of necessary and unnecessary lab tests of greater than 80% was achieved for all eight lab tests. Sensitivity and specificity were satisfactory for all the outcomes. An average reduction of 50% of the lab tests was obtained. This is an improvement from previously reported similar studies with average performance 37% by [1-3]. CONCLUSIONS: Reducing frequent lab testing and the potential clinical and financial implications are an important issue in intensive care. In this work we present an artificial intelligence method to predict the benefit of proposed future laboratory tests. Using ICU data from 746 patients with gastrointestinal bleeding, and eleven measurements, we demonstrate high accuracy in predicting the likely information to be gained from proposed future lab testing for eight common GI related lab tests. Future work will explore applications of this approach to a range of underlying medical conditions and laboratory tests.
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Inteligência Artificial/estatística & dados numéricos , Hemorragia Gastrointestinal/diagnóstico , Unidades de Terapia Intensiva/normas , Laboratórios/normas , Monitorização Ambulatorial da Pressão Arterial , Transfusão de Sangue , Feminino , Frequência Cardíaca , Humanos , Masculino , Modelos Estatísticos , Oxigênio/análise , Valor Preditivo dos Testes , Respiração , Sensibilidade e Especificidade , TemperaturaRESUMO
BACKGROUND AND PURPOSE: Chemokines orchestrate neutrophil recruitment to inflammatory foci. In the present study, we evaluated the participation of three chemokines, KC/CXCL1, MIP-2/CXCL2 and LIX/CXCL5, which are ligands for chemokine receptor 2 (CXCR2), in mediating neutrophil recruitment in immune inflammation induced by antigen in immunized mice. EXPERIMENTAL APPROACH: Neutrophil recruitment was assessed in immunized mice challenged with methylated bovine serum albumin, KC/CXCL1, LIX/CXCL5 or tumour necrosis factor (TNF)-alpha. Cytokine and chemokine levels were determined in peritoneal exudates and in supernatants of macrophages and mast cells by elisa. CXCR2 and intercellular adhesion molecule 1 (ICAM-1) expression was determined using immunohistochemistry and confocal microscopy. KEY RESULTS: Antigen challenge induced dose- and time-dependent neutrophil recruitment and production of KC/CXCL1, LIX/CXCL5 and TNF-alpha, but not MIP-2/CXCL2, in peritoneal exudates. Neutrophil recruitment was inhibited by treatment with reparixin (CXCR1/2 antagonist), anti-KC/CXCL1, anti-LIX/CXCL5 or anti-TNF-alpha antibodies and in tumour necrosis factor receptor 1-deficient mice. Intraperitoneal injection of KC/CXCL1 and LIX/CXCL5 induced dose- and time-dependent neutrophil recruitment and TNF-alpha production, which were inhibited by reparixin or anti-TNF-alpha treatment. Macrophages and mast cells expressed CXCR2 receptors. Increased macrophage numbers enhanced, while cromolyn sodium (mast cell stabilizer) diminished, LIX/CXCL5-induced neutrophil recruitment. Macrophages and mast cells from immunized mice produced TNF-alpha upon LIX/CXCL5 stimulation. Methylated bovine serum albumin induced expression of ICAM-1 on mesenteric vascular endothelium, which was inhibited by anti-TNF-alpha or anti-LIX/CXCL5. CONCLUSION AND IMPLICATIONS: Following antigen challenge, CXCR2 ligands are produced and act on macrophages and mast cells triggering the production of TNF-alpha, which synergistically contribute to neutrophil recruitment through induction of the expression of ICAM-1.
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Quimiocina CXCL1/imunologia , Quimiocina CXCL5/imunologia , Neutrófilos/imunologia , Peritonite/imunologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Anticorpos/farmacologia , Bovinos , Quimiocina CXCL1/farmacologia , Quimiocina CXCL5/farmacologia , Molécula 1 de Adesão Intercelular/biossíntese , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Mastócitos/imunologia , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peritonite/metabolismo , Receptores de Interleucina-8A/antagonistas & inibidores , Receptores de Interleucina-8B/antagonistas & inibidores , Receptores de Interleucina-8B/biossíntese , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Albumina Sérica/imunologia , Sulfonamidas/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/imunologiaRESUMO
This study assessed the effect of the agonist 15d-PGJ(2) administered into the rat temporomandibular joint (TMJ) on nociceptive behavioral and the anti-inflammatory potential of this prostaglandin on TMJ. It was observed that 15-deoxy-(Delta12,14)-prostaglandin J(2) (15d-PGJ(2)) significantly reduced formalin-induced nociceptive behavior in a dose dependent manner, however injection of 15d-PGJ(2) into the contralateral TMJ failed to reduce such effects. This antinociceptive effect is dependent on peroxisome proliferator-activated receptors-gamma (PPAR-gamma) since pre-treatment with GW9662 (PPAR-gamma receptor antagonist) blocked the antinociceptive effect of 15d-PGJ(2) in the TMJ. In addition, the antinociceptive effect of 15d-PGJ(2) was also blocked by naloxone suggesting the involvement of peripheral opioids in the process. Confirming this hypothesis pre-treatment with kappa, delta, but not mu receptor antagonists significantly reduced the antinociceptive effect of 15d-PGJ(2) in the TMJ. Similarly to opioid agonists, the 15d-PGJ(2) antinociceptive action depends on the nitric oxide (NO)/guanilate cyclase (cGMP)/ATP-sensitive potassium channel blocker(K(+)(ATP)) channel pathway since it was prevented by the pre-treatment with the inhibitors of nitric oxide synthase (NOS; aminoguanidine), cGMP (ODQ), or the K(+)(ATP) (glibenclamide). In addition, 15d-PGJ(2) (100 ng/TMJ) inhibits 5-HT-induced TMJ hypernociception. Besides, TMJ treated with 15d-PGJ(2) showed lower vascular permeability, assessed by Evan's Blue extravasation, and also lower neutrophil migration induced by carrageenan administration. Taken together, these results demonstrate that 15d-PGJ(2) has a potential peripheral antinociceptive and anti-inflammatory effect in the TMJ via PPAR-gamma activation. The results also suggest that 15d-PGJ(2) induced-peripheral antinociceptive response in the TMJ is mediated by kappa/delta opioid receptors by the activation of the intracellular l-arginine/NO/cGMP/K(+)(ATP) channel pathway. The pharmacological properties of the peripheral administration of 15d-PGJ(2) highlight the potential use of this PPAR-gamma agonist on TMJ inflammatory pain conditions.
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Analgésicos/farmacologia , Dor/tratamento farmacológico , Prostaglandina D2/análogos & derivados , Receptores Opioides delta/metabolismo , Receptores Opioides kappa/metabolismo , Articulação Temporomandibular/efeitos dos fármacos , Analgésicos/administração & dosagem , Animais , GMP Cíclico/antagonistas & inibidores , GMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Formaldeído , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Canais KATP/antagonistas & inibidores , Canais KATP/metabolismo , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , PPAR gama/antagonistas & inibidores , PPAR gama/metabolismo , Dor/induzido quimicamente , Dor/metabolismo , Prostaglandina D2/administração & dosagem , Prostaglandina D2/farmacologia , Ratos , Ratos Wistar , Receptores Opioides delta/antagonistas & inibidores , Receptores Opioides kappa/antagonistas & inibidores , Receptores Opioides mu/antagonistas & inibidores , Receptores Opioides mu/metabolismo , Serotonina/metabolismo , Transdução de Sinais , Articulação Temporomandibular/metabolismoRESUMO
We retrospectively analysed 33 children and adolescents who had been hospitalized in a liver transplant unit within the previous 10 years for acute liver failure (ALF). The patients' age varied between 2 months and 15 years of age (median 6.2 +/- 5.3), and 21 (63%) were male. Thirteen patients (39%) were immunoglobulin-M anti-hepatitis A virus (HAV) sero-positive. Eleven cases (33%) had an undetermined aetiology. The 13 children with HAV ALF were between 17 months and 15.6 years of age (median 5.8 +/- 4.6) and eight were male (61.5%). All were on a list for urgent liver transplant. Of these, five (38%) died while waiting for a liver. Only one patient recovered spontaneously. Seven patients received a liver transplant; three died in the immediate postoperative period and one died 45 days after transplant. Three children are alive 1, 2 and 5 years after transplant. We conclude that HAV was the most frequent cause of ALF, which had high mortality even when a liver transplant was possible. The results support universal HAV vaccination in this area.
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Vírus da Hepatite A , Hepatite A/complicações , Falência Hepática Aguda/epidemiologia , Falência Hepática Aguda/etiologia , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Hepatite A/imunologia , Hepatite A/mortalidade , Anticorpos Anti-Hepatite A/sangue , Humanos , Lactente , Falência Hepática Aguda/mortalidade , Falência Hepática Aguda/cirurgia , Transplante de Fígado/mortalidade , Transplante de Fígado/estatística & dados numéricos , Masculino , Estudos RetrospectivosRESUMO
Direct methylation of [60]fullerene via a gas-phase reaction in a CH4/H2 atmosphere was performed using a modified hot filament chemical vapor deposition method. Pressures were varied from 10 to 60 mbar and the substrate was maintained at 690 degrees C. High-resolution matrix-assisted laser desorption ionization (MALDI) mass spectrometry analysis showed signals corresponding to C60H18-2n(H,CH3)n. Collision-induced dissociation experiments confirmed a maximum of 18 ligands possible to the [60]fullerene cage.
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Fulerenos/química , Gases , Espectroscopia de Ressonância Magnética , Metilação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Amostras de seis lotes de sete marcas de salames tipo italiano foram analisadas quanto a aminas bioativas e características físico-químicas de qualidade. Oito das 10 aminas pesquisadas foram detectadas em todas as amostras com teores totais de 28,33 a 53,27mg/100g. A tiramina foi a amina predominante seguida da putrescina e da cadaverina. Todas as marcas apresentaram teores de tiramina capazes de causar efeito tóxico em indivíduos sensíveis dependendo da quantidade ingerida. Duas marcas apresentaram também teores potencialmente tóxicos de histamina e de feniletilamina. Nenhuma das marcas atendeu à legislação em pelo menos um parâmetro físico-químico. Os teores de umidade e de açucares totais foram as características com maior percentual de não-atendimento. Os teores de cinzas variaram de 5,54 a 7,12g/100g, sendo os cloretos 66 a 79 por cento desses teores. As amostras apresentaram valores de pH de 4,86 a 5,78, acidez de 16,61 a 55,03ml NaOH N/100g e índice de peróxidos de não detectado a 334,82mEq/kg.
Six batches of seven brands of Italian sausages purchased in Belo Horizonte, MG were analyzed for bioactive amines and physico-chemical characteristics. Eight out of 10 amines investigated were detected in every sample with total levels varying from 28.33 to 53.27mg/100g. Tyramine was the predominant amine followed by putrescine and cadaverine. Every brand contained toxic tyramine levels for sensitive individuals depending on the amount of sausage consumption. Two brands also contained toxic levels of histamine and phenylethylamine. No brand was in conformity to legislation levels for at least one physico-chemical parameter. The highest discrepancies to legislation levels were observed for moisture and total sugar contents. The levels of ash varied from 5.54 to 7.12g/100g, with chlorides representing 66 to 79 percent of the levels.The pH varied from 4.86 to 5.78, acidity from 16.61 to 55.03ml NaOH N/100g and peroxide values from 0.0 (no detected) to 334.82mEq/kg.
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Alimentos/toxicidade , Aminas/toxicidade , Fenômenos Químicos/métodos , Análise de Alimentos/métodos , Controle de QualidadeRESUMO
OBJECTIVE: To review the clinical aspects and the theoretical basis of liver transplantation in children, focusing mainly pre and post surgical periods. METHODS: References were obtained from computerized search in the National Library of Medicine (Medline), recent review articles, and personal files. RESULTS: Great development has occurred in surgical techniques, in organ preservation, in postoperative care, and in immunosuppression methods after the first liver transplantation surgery took place in a child with biliary atresia in 1963. Liver transplantation has become an efficient therapy, widely accepted and used in all age groups. It is a very complex procedure, with many professionals involved and with several legal, ethical and economical implications. We review in this article the clinical aspects before transplantation, including indications, contraindications, clinical and laboratory evaluations, as well as postsurgical aspects, both in the immediate period, after the 1st week, and the long-term outcome, discussing the complications and the treatment of each. CONCLUSIONS: Liver transplantation has dramatically improved the survival of pediatric patients with chronic hepatic diseases. Patients of liver transplantation in the pediatric age group present today survival rates of 90% in the different transplantation centers.
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The management of 50 AIDS patients by traditional hospital admission (25 cases) and outpatient clinics (25 cases) was studied between August and November 1995 in the Department of Infectious and Parasitic Diseases of the Federal University Hospital. The most costly items of expenditure were hospital services and consumable materials. Comparison of costs was complicated by differences in clinical status of the patients in the two groups. The choice of treatment was much more dependent on clinical status than on sociodemographic factors. Traditional hospital admission tended to be associated with the poorest patients. The rationalization of care based on cost-benefit analysis requires much future work.
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Síndrome da Imunodeficiência Adquirida/terapia , Síndrome da Imunodeficiência Adquirida/diagnóstico , Síndrome da Imunodeficiência Adquirida/economia , Adolescente , Adulto , Instituições de Assistência Ambulatorial , Análise Custo-Benefício , Custos e Análise de Custo , Feminino , Hospitalização , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To analyze the evolution of pediatric patients chosen for hepatic transplantation. METHODS: A review was made of the clinical charts of the first 65 children and adolescents with chronic liver disease, aged 5 months to 19 years (X = 6.8%), chosen for liver transplantation during the period of August 1994 to March 1996. Data refer to the patients' demographic characteristics, etiology of their liver disease, their psychosocial situation and of their parents, and their clinical and laboratorial evaluation. According to the severity of the disease, patients were classified as active (waiting for a donor), in evaluation, inactive (compensated liver disease), and excluded for psychosocial or medical conditions, or because of bad indication. RESULTS: Eight patients (12%) received transplantation, and one of them died. Seven (11%) died when in evaluation or waiting for a donor. Ten patients (15%) were excluded from the waiting list: 6 for social problems, and 4 for medical problems. No patient was excluded for bad indication. Six patients are in the active list, waiting for donor. The other 23 patients (35%) are in evaluation, and 11 (17%) are classified as inactive in the waiting list. CONCLUSIONS: Eleven patients (17%) were not operated on due to the advanced stage of the liver disease. We emphasize the necessity of organ donation, and the early contact of the patients with a reference center.
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Polarization microscopy disclosed the presence of strongly birefringent intracellular structures in the basal cells of the epidermis of the tadpole of the anuran Pseudis paradoxus. The electron microscopic picture of the birefringent structures showed that they were composed of thick intermediate filaments (average diameter: 11.2 +/- 0.8 nm) oriented in a parallel disposition to form closely packed bundles which attached to the hemidesmosomes present on the basal surface of the cells of the basal layer of the epidermis. Thinner intermediate filaments (average diameter: 8.2 +/- 0.8 nm) were localized to the cortical zone of the cytoplasm; these thinner intermediate filaments converged upon the sites of cell-to-cell adhesion (desmosomes).