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Riad N Younes

Publications and source records attributed to Riad N Younes.

12 recordsLinked to original sources
PubMed2006

Intestinal ischemia/reperfusion induces bronchial hyperreactivity and increases serum TNF-alpha in rats.

INTRODUCTION: Intestinal or hepatic ischemia/reperfusion induces acute lung injury in animal models of multiple organ failure. Tumor necrosis factor (TNF)- alpha is involved in the underlying inflammatory mechanism of acute respiratory distress syndrome. Although the inflammatory cascade leading to acute respiratory distress syndrome has been extensively investigated, the mechanical components of acute respiratory distress syndrome are not fully understood. Our hypothesis is that splanchnic ischemia/reperfusion increases airway reactivity and serum TNF-alpha levels. OBJECTIVE: To assess bronchial smooth muscle reactivity under methacholine stimulation, and to measure serum TNF-alpha levels following intestinal and/or hepatic ischemia/reperfusion in rats. METHOD: Rats were subjected to 45 minutes of intestinal ischemia, or 20 minutes of hepatic ischemia, or to both (double ischemia), or sham procedures (control), followed by 120 minutes of reperfusion. The animals were then sacrificed, and the bronchial response to increasing methacholine molar concentrations (10(-7) to 3 x 10(-4)) was evaluated in an ex-vivo bronchial muscle preparation. Serum TNF-alpha was determined by the L929-cell bioassay. RESULTS: Bronchial response (g/100 mg tissue) showed increased reactivity to increasing methacholine concentrations in the intestinal ischemia and double ischemia groups, but not in the hepatic ischemia group. Similarly, serum TNF-alpha (pg/mL) concentration was increased in the intestinal ischemia and double ischemia groups, but not in the hepatic ischemia group. CONCLUSION: Intestinal ischemia, either isolated or associated with hepatic ischemia, increased bronchial smooth muscle reactivity, suggesting a possible role for bronchial constriction in respiratory dysfunction following splanchnic ischemia/reperfusion. This increase occurred in concomitance with serum TNF-alpha increase, but whether the increase in TNF-alpha caused this bronchial contractility remains to be determined.

Animals↗
PubMed2006

Evaluation of gastric greater curvature invagination for weight loss in rats.

BACKGROUND: Many bariatric endocopic or surgical procedures performed today reduce gastric capacity and/or induce an early sensation of satiety, alone or in combination with a distal enteric intervention. A form of prosthetic gastric wrap was used in the past for treating obesity with a high rate of reintervention. Nissen gastric fundoplication used in the treatment of gastroesophageal reflux disease induces a small but significant weight loss. We report the effect of gastric greater curvature invagination on weight in rats. METHODS: 30 rats were randomly divided into 3 groups. 10 rats in the first group (sham) were anesthesized and weighed. The rats from the second group (lap) were in addition submitted to a laparotomy plus visceral manipulation. In the third group (inv), invagination of the greater curvature of the stomach was added. All animals were weighed on the 7th and 21st days. They were then autopsied on the 21st day. RESULTS: The mean body weight of the invagination group became statistically less than the laparotomy and sham groups at 7 and 21 days. The mean weight of the peritesticular fat pad from the inv group was also significantly less than from the sham group but not different from the lap group. CONCLUSION: Gastric greater curvature invagination significantly decreases weight in rats.

Analysis of Variance↗
PubMed2006

Antibacterial and cytotoxic activity of Brazilian plant extracts--Clusiaceae.

Twelve extracts obtained from nine plants belonging to six different genera of Clusiaceae were analyzed against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Enterococcus faecalis) bacteria using the microdilution broth assay. Tovomita aff. longifolia, T. brasiliensis, Clusia columnaris, Garcinia madruno, Haploclathra paniculata, and Caraipa grandifolia extracts showed significant results against the bacteria. The organic extract obtained from the leaves of T. aff. longifolia showed minimal inhibitory concentration (MIC) = 70 microg/ml and minimal bactericidal concentration (MBC) = 90 microg/ml against E. faecalis and the organic extract made with the stem of C. columnaris showed MIC = 180 microg/ml and MBC = 270 microg/ml against P. aeruginosa. None of the antibacterial extracts showed lethal activity against brine shrimp nauplii. On the other hand, both aqueous and organic extracts obtained from the aerial organs of Vismia guianensis that were cytotoxic to brine shrimp nauplii did not show a significant antibacterial activity in the assay.

Animals↗
PubMed2004

Nonsmall cell lung cancer: evaluation of 737 consecutive patients in a single institution.

OBJECTIVE: To analyze surgical and pathological parameters and outcome and prognostic factors of patients with nonsmall cell lung cancer (NSCLC) who were admitted to a single institution, as well as to correlate these findings to the current staging system. METHOD: Seven hundred and thirty seven patients were diagnosed with NSCLC and admitted to Hospital do Cancer A. C. Camargo from 1990 to 2000. All patients were included in a continuous prospective database, and their data was analyzed. Following staging, a multidisciplinary team decision on adequate management was established. Variables included in this analysis were age, gender, histology, Karnofsky index, weight loss, clinical stage, surgical stage, chemotherapy, radiotherapy, and survival rates. RESULTS: 75.5% of patients were males. The distribution of histologic type was squamous cell carcinoma 51.8%, adenocarcinoma 43.1%, and undifferentiated large cell carcinoma 5.1%. Most patients (73%) presented significant weight loss and a Karnofsky index of 80%. Clinical staging was IA 3.8%, IB 9.2%, IIA 1.4%, IIB 8.1%, IIIA 20.9%, IIIB 22.4%, IV 30.9%. Complete tumor resection was performed in 24.6% of all patients. Surgical stage distribution was IA 25.3%, IB 1.4%, IIB 17.1%, IIIA 16.1%, IIIB 20.3%, IV 11.5%. Chemotherapy and radiotherapy were considered therapeutic options in 43% and 72%, respectively. The overall 5-year survival rate of nonsmall cell lung cancer patients in our study was 28%. Median survival was 18.9 months. CONCLUSIONS: Patients with NSCLC who were admitted to our institution presented with histopathologic and clinical characteristics that were similar to previously published series in cancer hospitals. The best prognosis was associated with complete tumor resection with lymph node dissection, which is only achievable in earlier clinical stages.

Adolescent↗
PubMed2003

Computed tomography-guided biopsy of mediastinal lesions: fine versus cutting needles.

PURPOSE: To report the experience of a radiology department in the use of computed tomography guided biopsies of mediastinal lesions with fine and cutting needles, describing the differences between them. The results of adequacy of the sample and histologic diagnoses are presented according to the type of needle used. METHODS: We present a retrospective study of mediastinal biopsies guided by computed tomography performed from January 1993 to December 1999. Eighty-six patients underwent mediastinal biopsy in this period, 37 with cutting needles, 38 with fine needles, and 11 with both types (total of 97 biopsies). RESULTS: In most cases, it was possible to obtain an adequate sample (82.5%) and specific diagnosis (67.0%). Cutting-needle biopsy produced a higher percentage of adequate samples (89.6% versus 75.5%, P = 0.068) and of specific diagnosis (81.3% versus 53.1%, P = 0.003) than fine-needle biopsy. There were no complications that required intervention in either group. CONCLUSION: Because they are practical, safe, and can provide accurate diagnoses, image-guided biopsies should be considered the procedure of choice in the initial exploration of patients with mediastinal masses. In our experience, cutting needles gave higher quality samples and diagnostic rates. We recommend the use of cutting needles as the preferred procedure.

Adolescent↗
PubMed2003

Pulmonary metastases tumor doubling time: assessment by computed tomography.

Growth rate is a prognostic factor for pulmonary metastases treatment. We used computed tomography (CT) to quantify tumor doubling time (Tdt) variation of pulmonary metastases in the same patient, from different histologies and sizes. We prospectively evaluated chest CTs of patients with pulmonary metastases under no cancer treatment. Tdt of 408 pulmonary nodules in 21 patients was determined. One hundred twenty-three (30%) remained unaltered, 44 (11%) had reduction, and 241 (59%) increased in size. Nodules that grew presented a mean Tdt of 118 +/- 134 days (range: 22-930 days). There was high intraindividual variability of mean Tdt with no difference between histologies. Smaller nodules presented greater tendency to grow, and lower Tdt. There is large variation in clinical behavior for pulmonary metastases in the same patient. Each nodule should be evaluated independently. Selection of a single nodule to evaluate metastatic disease behavior could influence the therapeutic decision.

Adult↗
PubMed2002

Surgical resection of unilateral lung metastases: is bilateral thoracotomy necessary?

UNLABELLED: Surgical resection of lung metastases is routine procedure for selected patients with pulmonary nodules and solid tumors. In some cases, patients present with unilateral pulmonary metastases amenable to surgical resection. Surgeons are still divided between unilateral approach directed to the radiologically detected nodules, or bilateral exploratory thoracotomy. This study evaluates the need for bilateral thoracotomy in patients diagnosed with unilateral lung metastases. A retrospective evaluation was made of a prospective database from a single institution (1990-1997) of all consecutive patients (n = 267) diagnosed on admission with unilateral (n = 179) or bilateral (n= 88) lung nodules. Ipsilateral thoracotomy was performed on all patients with unilateral disease. Bilateral thoracotomy was performed on all patients with bilateral lung metastases. HISTOLOGY: adenocarcinoma (25%), osteosarcoma (23%), squamous cell carcinoma (18%), soft-tissue sarcoma (18%), and other (16%). Median follow-up was 17 months. Contralateral disease-free survival and overall survival were determined. Univariate and multivariate analyses were performed to determine prognostic factors for overall and contralateral disease-free survival. The two groups of patients with confirmed bilateral metastases (synchronous or metachronous) were compared. Actuarial overall 5-year survival was 34.9%. Contralateral recurrence-free 6-month, 12-month, and 5-year survival were 95%, 89%, and 78%, respectively. Patients who experienced recurrence in the contralateral lung within 3, 6, or 12 months had an overall 5-year survival rate of 24%, 30%, and 37%, respectively. When patients with recurrence in the contralateral lung were compared to patients with bilateral metastases on admission, there was no significant difference in overall survival. Only histology and the number of pathologically proven metastases significantly (p < 0.05) predicted recurrence in the contralateral lung. Bilateral exploration of unilateral lung metastases is not warranted in all cases. Most patients will have only unilateral disease, and delaying contralateral thoracotomy until disease is detected radiologically does not appear to affect outcome.

Adenocarcinoma↗
PubMed2002

When to remove a chest tube? A randomized study with subsequent prospective consecutive validation.

BACKGROUND: Operative procedures on the pleural space are usually managed by chest tube drainage. Timing for removing the tube is empirically established, with wide variation among surgeons. Our objective was to evaluate the effectiveness and safety of establishing a volume of 200 mL/d of uninfected drainage as a threshold for removal of chest tube, as compared with more frequently used volumes of 100 and 150 mL/d. STUDY DESIGN: A prospective randomized study was performed in a single institution. Patients (n = 139) submitting to pleural drainage after surgical procedures were randomized to one of three groups, defined by the planned timing of chest tube removal (depending on the threshold volume per day of pleural fluid drained): G-100 (< or = 100 mL/d, n = 44); G-150 (< or =150 mL/d, n = 58); and G-200 (< or = 200 mL/d, n = 37). Subsequently, another 91 consecutive patients had chest tubes removed when drainage was less than 200 mL/d (G-val, prospective validation group). All patients had similar discharge and 60-day followup. Drainage time, hospital stay, and reaccumulation rate were registered. RESULTS: Drainage time (median days: 3.5 for G-100, 3 for G-150, 3 for G-200, 3 for G-val) and hospital stay (median days: 4 for G-100, 3 for G-150, 3 for G-200, 3 for G-val) were not statistically different among groups. Radiologic reaccumulation rates were 9.1% for G-100, 13.1% for G-150, 5.4% for G-200, and 10.9% for G-val, and the thoracenteses rates were 2.3%, 0.8%, 2.7%, and 3.3%, respectively, with no major differences among groups (G-100 versus G-150 versus G-200; G-200 versus G-val). CONCLUSIONS: Increasing the threshold of daily drainage to 200 mL before removing the chest tube did not markedly affect drainage, hospitalization time, or overall costs, nor did it increase the likelihood of major pleural fluid reaccumulation. This volume (200 mL/d) could be recommended for chest tube withdrawal decision for uninfected pleural fluid with no evidence of air leaks.

Chest Tubes↗
PubMedDate not supplied

Computed tomography-guided cutting needle biopsy of pulmonary lesions.

PURPOSE: To report the experience of a radiology department in the use of computed tomography - guided cutting needle biopsy of pulmonary nodules, by evaluating diagnostic yield and incidence of complications. METHODS: This is a retrospective analysis of 52 consecutive patients who underwent lung lesion biopsy guided by computed tomography, performed between May 1997 and May 2000. Thirty-five patients were male and 17 were female, with ages ranging from 5 to 85 years (median, 62 years). The size of the lesions ranged from 1.8 to 15 cm (median, 5.4 cm). RESULTS: In a total of 52 biopsies of lung lesions, 51 biopsies (98.1%) supplied appropriate material for histopathological diagnosis, with 9 diagnosed (17.3%) as benign and 42 (80.8%) as malignant lesions. Specific diagnosis was obtained in 44 (84.6%) biopsies: 4 benign (9.1%) and 40 (90.9%) malignant lesions. The sensitivity, specificity, and accuracy of the cutting needle biopsies for determining presence of malignancy were 96.8%, 100%, and 97.2%, respectively. Complications occurred in 9 cases (17.3%), including 6 cases (11.5%) of small pneumothorax, 1 (1.9%) of hemoptysis, 1 (1.9%) of pulmonary hematoma, and 1 (1.9%) of thoracic wall hematoma. All had spontaneous resolution. There were no complications requiring subsequent intervention. CONCLUSION: The high sensitivity and specificity of the method and the low rate of complications have established cutting needle biopsy as an efficient and safe tool for the diagnosis of lung lesions. In our hospital, cutting needle biopsy is considered a reliable procedure for the evaluation of indeterminate pulmonary nodules.

Adolescent↗
PubMedDate not supplied

Hypertonic/hyperoncotic solution in hypovolemic patients: experience in the emergency room.

Hypertonic solutions have been studied extensively in the treatment of hypovolemic shock, both in experimental and clinical models. Safety, efficacy, and long-term effects on animals and patients have been evaluated. The present article reviews indications, safety, mortality rates, and outcome in patients with hemorrhagic hypovolemic shock who were treated after admission with a hypertonic/hyperoncotic solution under strict observation in the emergency room.

Adolescent↗