Fator de crescimento derivado de plaquetas humanas obtido por uma metodologia rápida e de baixo custo / Human platelet-derived growth factor obtained by means of a fast and inexpensive methodology

O fator de crescimento derivado de plaquetas (PDGF) é uma proteína catiônica armazenado principalmente nos grânulos-alfa plaquetário. O PDGF por ser altamente mitogênico, principalmente para fibroblastos e leiomiócitos, é de grande importância no processo de regeneração tecidual. Neste trabalho, o PDGF foi obtido a partir do lisado de plaquetas humanas (5 x 10 plaquetas/mL) vencidas, purificado por cromatografia de troca iônica em resina de CM-Sepharose. A proteína eluída na fração catiônica, foi identificada por anticorpos policlonais anti-PDGF (AA e BB) e, posteriormente, sua atividade mitogênica confirmada pela incorporação da [H3]-TdR usando fibroblastos da linhagem celular NIH/3T3 em cultura. A comparação entre os efeitos mitogênicos sobre o PDGF, fração catiônica, com uma proteína recombinante controle (PDGF-AB), revelou que a proteína parcialmente purificada induziu semelhante estimulação, 157.567 cpm e 165.796 cpm, respectivamente. Os resultados obtidos evidenciam a aplicabilidade dessas condições experimentais na obtenção do PDGF, preservando sua atividade biológica, através de procedimentos de baixa complexibilidade, eficiente e de custo operacional reduzido, possibilitando seu uso em experimentos de regeneração tecidual

Utility of routine admission chest radiographs in patients with acute gastrointestinal hemorrhage admitted to an intensive care unit.

PURPOSE: To determine the diagnostic yield of routine admission chest radiographs in patients with acute gastrointestinal (GI) hemorrhage and clinical predictors of radiographic abnormalities. PATIENTS AND METHODS: The study was a retrospective series of 202 adult patients with GI hemorrhage admitted to intensive care units at an academic medical center. Routine admission chest radiographs were obtained in 161 patients. These radiographs were reviewed by a study radiologist blinded to the study purpose. The radiologist scored radiographic abnormalities into categories of "minor" or "major," "new" or "previously known," and "with an intervention" or "without an intervention." Nominal logistic regression explored the data for clinical features that identified patients with major new radiographic abnormalities with or without an intervention. RESULTS: Minor radiographic abnormalities were noted in 23 (14.3%) patients, of whom 17 (10.6%) patients had "new" (previously unknown) abnormalities. No minor abnormality prompted a therapeutic or diagnostic intervention. Major radiographic abnormalities were detected in 21 (13.0%) patients, of whom 19 (11.8%) had new findings. Major new findings prompted interventions in only 9 (5.6%) of patients. A history of lung disease and an abnormal lung physical examination predicted major new radiographic findings (P = 0.0001, sensitivity 79%, negative predictive value 96%). These variables also identified major new abnormalities that prompted interventions (P = 0.007, sensitivity 89%, negative predictive value 99%). Use of the logistic regression model to select patients for admission chest radiographs decreased charges from $1,068 to $580 for each detected major new radiographic abnormality and from $2,254 to $1,087 for major new radiographic abnormalities that prompted an intervention. CONCLUSION: These data indicate that routine chest radiographs have a low yield in detecting major new radiographic abnormalities in patients with acute GI hemorrhage. Clinical criteria, available at the time of admission, may be useful for selecting patients for chest radiographic evaluations.

Pleural fluid chemical analysis in parapneumonic effusions. A meta-analysis.

Controversy exists regarding the clinical utility of pleural fluid pH, lactate dehydrogenase (LDH), and glucose for identifying complicated parapneumonic effusions that require drainage. In this report, we performed a meta-analysis of pertinent studies, using receiver operating characteristic (ROC) techniques, to assess the diagnostic accuracy of these tests, to determine appropriate decision thresholds, and to evaluate the quality of the primary studies. Seven primary studies reporting values for pleural fluid pH (n = 251), LDH (n = 114), or glucose (n = 135) in pneumonia patients were identified. We found that pleural fluid pH had the highest diagnostic accuracy for all patients with parapneumonic effusions as measured by the area under the ROC curve (AUC = 0.92) compared with pleural fluid glucose (AUC = 0.84) or LDH (AUC = 0.82). After excluding patients with purulent effusions, pH (AUC = 0.89) retained the highest diagnostic accuracy. Pleural fluid pH decision thresholds varied between 7.21 and 7.29 depending on cost-prevalence considerations. The quality of the primary studies was the major limitation in determining the value of pleural fluid chemical analysis. We conclude that meta-analysis of the available data refines the application of pleural fluid chemical analysis but a clearer understanding of the usefulness of these tests awaits more rigorous primary investigations.

Management of parapneumonic effusions. An analysis of physician practice patterns.

OBJECTIVE: To evaluate physician practices in managing patients with parapneumonic effusions and the impact of practice patterns on clinical outcome. DESIGN: Case series. SETTING: Private, tertiary care medical center. PATIENTS: Thirty-nine hospitalized patients with complicated parapneumonic effusions and a separate group of 191 patients admitted with community-acquired pneumonia. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Evaluation of physician practice patterns in managing complicated parapneumonic effusion and the impact of delaying thoracentesis (> or = 2 days after pleural fluid detection) or pleural drainage (> or = 2 days after pleural fluid criteria for drainage fulfilled) on duration of hospitalization, cost of hospitalization, and need for thoracotomy. RESULTS: Thirty-eight of the 39 patients with complicated parapneumonic effusions underwent thoracentesis that was "delayed" (5.7 +/- 3.1 days) in 16 patients. Delays in thoracentesis were associated with longer hospitalizations (P = .02). Laboratory tests ordered on nonpurulent pleural fluid were incomplete for 16 of 38 patients. Chest tube or surgical pleural drainage was delayed (4.2 +/- 3.5 days) in 10 of 38 patients who underwent thoracentesis. Delays in initiating drainage were associated with prolonged hospitalization (P = .04). Delaying interventions accounted for a mean cost increment per patient of $8462 for delayed thoracentesis and $9332 for delayed drainage. Of the 191 patients with community-acquired pneumonia, 99 (52%) had pleural effusions but only 15 (15%) underwent thoracentesis. CONCLUSIONS: Physicians commonly delay thoracentesis and chest tube drainage to observe parapneumonic effusions for improvement. This practice pattern is associated with longer and more costly hospitalizations.

Treatment with gammaglobulin preparation for intravenous use in children with humoral immunodeficiency: clinical and immunologic follow-up.

We have treated 23 children aged 6 to 15 years affected with agammaglobulinemia or severe hypogammaglobulinemia with IgG serum levels less than 100 mg/dL with IV gammaglobulin (Sandoglobulin), 150 to 300 mg/kg/3 wk for more than 3 years. The children suffered from severe and recurrent bacterial infections, mainly of the respiratory tract. They had been treated previously with IM gammaglobulin (0.8 ml/kg/3 wk), but their serum IgG values were never higher than 100 mg/dL. We compared the data of the follow-up after 3 years of treatment with IV gammaglobulin and the follow-up after 2 years course of IM gammaglobulin. Minor adverse reactions (chills, fever, abdominal pain) were observed only in some children during the first months of therapy. These data demonstrate that the number of infections or days with fever, in bed, or in hospital dramatically decreased during IV Ig therapy, while IgG serum levels increased to approximately normal values. IV Ig is a safe and effective treatment for patients with humoral immunodeficiency.