80 research outputs found
Prospective observational study on antibiotic-associated bloody diarrhea: report of 21 cases with a long-term follow-up from Turkey
WOS: 000303826200012PubMed ID: 22433794Objective Antibiotic-associated hemorrhagic colitis is a distinct form of antibiotic-associated bloody diarrhea (AABD) in which Clostridium difficile is absent. Although the cause is not exactly known, reports have suggested the role of Klebsiella oxytoca and/or C. difficile. Materials and Methods Between 2001 and 2006, stool samples of 21 consecutive patients with AABD were cultured for common enteric pathogens and K. oxytoca, and were tested for the presence of parasites and C. difficile toxin A + B within the first 24 h of their initial admission and a colonoscopy was performed when available. The patients were followed up prospectively by telephone interviews. Results The occurrence of symptoms ranged between 6 h and 14 days following the first dose of the antibiotic responsible and the duration of the AABD ranged between 6 h and 21 days. The antibiotic responsible was oral ampicillin/sulbactam in 18 (85%) cases. C. difficile toxin A + B production by enzyme-linked immunosorbent assay and K. oxytoca growth in stool cultures were detected in six (29%) and 11 (51%) of 21 patients, respectively. Endoscopic morphology and histology in a limited number of patients revealed no more than a nonspecific inflammation and acute colitis, respectively. Conclusion This study confirms that antibiotic-associated hemorrhagic colitis, as a distinct entity in relation to K. oxytoca, is seen in half of the patients with AABD. Most of the cases are seen within a week following the antibiotic use. Almost all of the patients did not develop any flares during the long-term antibiotic-free follow-up. In some of the patients with AABD, there was coexistence of K. oxytoca with C. difficile toxin A + B. Eur J Gastroenterol Hepatol 24: 688-69
A Clinical Experience: Endoscopic and Surgical Management of Bezoars
Objective:This study aims to evaluate the cases treated for gastrointestinal obstruction due to bezoar in terms of clinical-radiological-endoscopic features and treatment methods.Method:Among the patients treated for acute mechanical intestinal obstruction (AMIO) in our hospital between January 2014 and December 2019, 33 patients with bezoar-related AMIO were included in the study. The cases were examined in terms of the presence of comorbidity, tomography and endoscopy features, and treatment modalities.Results:A history of intraabdominal surgery was found in 82% of patients (n=27) and a history of upper gastrointestinal surgery in 60% (n=20). DM accompanied in 27% of the patients (n=9) and psychiatric disorder in 18% (n=6). With computered tomography, gastric dilatation was observed in 9 patients, jejunal in 9 patients, jejunoileal in 9 patients, and dilatation in all bowel segments in 6 patients. Endoscopy was performed in 12 patients; 9 had peptic ulcers, 3 were normal. Seventeen cases were treated with laparotomy, 9 cases with a laparoscopic enterotomy, and 3 cases with endoscopic procedures. 4 cases were treated with a Coca-Cola injection from a nasogastric catheter, which was successful.Conclusion:It is difficult to diagnose bezoar-related AMIO with clinical findings. Radiological and endoscopic methods are important in diagnosis. Although endoscopic methods are also used successfully for therapeutic purposes, surgical methods are used in distal locations and complicated cases
Partial Atrophy of The Pancreas in Endoscopic Ultrasonography may be a Sign of Pancreatic Cancer
Introduction:Solid and/or cystic lesions of the pancreas can range from benign to malignant, and the differential diagnosis of pancreatic carcinoma (PC) is of uttermost importance. Endoscopic ultrasonography (EUS) is frequently used and is helpful in detecting small (37 U/mL, and partial atrophy in the pancreas were independently associated with PC. For solid lesions, age and size >24 mm; and for cystic lesions, male gender and mucinous pathology were independently associated with PC. Thirty-six of the cystic lesions had mucinous pathology. Cyst and serum CEA, string sign, wesung connection, and tail location was associated with mucinous pathology. Cyst CEA cut-off for mucinous pathology was 80 ng/mL (AUC: 0.89). CEA >80 ng/mL was found to be associated with mucinous pathology in multivariate analysis.Conclusion:High CA19-9, solid lesion, and lesion-related partial atrophy of the pancreas are associated with PC, and these should be alarming for clinicians in practice. The mucinous character, which is a significant risk of PC for cystic lesions, can be optimally defined with the CEA cut-off value of 80 ng/mL
The prediction of swell percent and swell pressure by using neural networks
Expansive soils exhibit significantly high volumetric deformations and so pose a serious threat to stability of the structures and foundations. Thus, determination of their swelling properties (i.e. swelling potential and swell pressure) becomes essential. However, measurement of the swelling properties is time-consuming and requires special and expensive equipment. With this in view, efforts were made to develop artificial neural network (ANN) and multiple regression analysis (MRA) models that can be employed for estimating swell percent and swell pressure. To achieve this, the results of free swell tests performed on statically compacted specimens of Kaolinite-Bentonite clay mixtures with varying soil properties were used. Two different ANN (ANN-1 and ANN-2) and MRA (MRA-1 and MRA-2) models have been developed: ANN-1 and MRA-1 models for predicting swell percent and ANN-2 and MRA-2 models for predicting swell pressure. The results obtained from ANN and MRA models were compared vis-à-vis those obtained from the experiments. The values predicted from the ANN models match the experimental values much better than those obtained from MRA models. Moreover, several performance indices such as determination coefficient (), variance account for (VAF), mean absolute error (MAE), and root mean square error (RMSE) were calculated to check the prediction capacity of the ANN and MRA models developed. The obtained indices make it clear that the constructed ANN models have shown higher prediction performance than MRA models. It has been demonstrated that the ANN models can be used satisfactorily to predict swell percent and swell pressure as a rapid inexpensive substitute for laboratory techniques
Değişik Anadolu kumlarının kama kesme, üç eksenli ve kesme kutusu deneylerindeki dayanımı.
Past studies on sands have shown that the shear strength measured in plane strain tests was higher than that measured in triaxial tests. It was observed that this difference changed with the friction angle fcv at constant volume related to the mineralogical composition. In order to investigate the difference in strength measured in the wedge shear test, which approaches the plane strain condition, in the triaxial test, and in the shear box test, Anatolian sands were obtained from different locations in Turkey. Mineralogical analyses, identification tests, wedge shear tests (cylindrical wedge shear tests (cylwests) and prismatic wedge shear tests (priswests)), triaxial tests, and shear box tests were performed on these samples. In all shear tests, the shear strength measured was found to increase with the inclination d of the shear plane to the bedding planes. Thus, cylwests (d = 60o) iii yielded higher values of internal friction f by about 3.6o than priswests (d = 30o) under normal stresses between 17 kPa and 59 kPa. Values of f measured in cylwests were about 1.08 times those measured in triaxial tests (d ₈ 65o), a figure close to the corresponding ratio of 1.13 found by past researchers between actual plane strain and triaxial test results. There was some indication that the difference between cylwest and triaxial test results increased with the fcv value of the samples. With the smaller d values (30o and 40o), priswests yielded nearly the same f values as those obtained in triaxial tests under normal stresses between 20 kPa and 356 kPa. Shear box tests (d =0o) yielded lower values of f than cylwests (by about 7.9o), priswests (by about 4.4o), and triaxial tests (by about 4.2o) under normal stresses between 17 kPa and 48 kPa. It was shown that the shear strength measured in shear box tests showed an increase when d was increased from 30o to 60o; this increasePh.D. - Doctoral Progra
The use of neural networks for CPT-based liquefaction screening
This study deals with development of two different artificial neural network (ANN) models: one for predicting cone penetration resistance and the other for predicting liquefaction resistance. For this purpose, cone penetration numerical simulations and cyclic triaxial tests conducted on Ottawa sand–silt mixes at different fines content were used. Results obtained from ANN models were compared with simulation and experimental results and found close to them. In addition, the performance indices such as coefficient of determination, root mean square error, mean absolute error, and variance were used to check the prediction capacity of the ANN models developed. Both ANN models have shown a high prediction performance based on the performance indices. It has been demonstrated that the ANN models developed in this study can be employed for predicting cone penetration and liquefaction resistances of sand–silt mixes quite efficiently
- …