Drop Weight Impact Test on Prepacked Aggregate Fibrous Concrete—An Experimental Study

In recent years, prepacked aggregate fibrous concrete (PAFC) is a new composite that has earned immense popularity and attracted researchers globally. The preparation procedure consists of two steps: the coarse aggregate is initially piled into a mold to create a natural skeleton and then filled with flowable grout. In this instance, the skeleton was completely filled with grout and bonded into an integrated body due to cement hydration, yielding a solid concrete material. In this research, experimental tests were performed to introduce five simple alterations to the ACI 544 drop weight impact test setup, intending to decrease result dispersion. The first alteration was replacing the steel ball with a steel bar to apply a line impact instead of a single point impact. The second and third introduced line and cross notched specimens at the specimen’s top surface and the load applied through a steel plate of cross knife-like or line load types. These modifications distributed impact load over a broader area and decrease dispersion of results. The fourth and fifth were bedding with sand and coarse aggregate as an alternate to the solid base plate. One-hundred-and-eight cylindrical specimens were prepared and tested in 12 groups to evaluate the suggested alteration methods. Steel and polypropylene fibers were utilized with a dosage of 2.4% to produce PAFC. The findings indicated that the line notched specimens and sand bedding significantly decreased the coefficient of variation (COV) of the test results suggesting some alterations. Using a cross-line notched specimen and line of impact with coarse bedding also effectively reduced COV for all mixtures.     

Spontaneous and simultaneous complete bilateral rupture of the quadriceps tendon in a patient receiving hemodialysis: A case report and literature review

The spontaneous and simultaneous rupture of both quadriceps tendons is uncommon and has rarely been reported in the literature. The current case involves a 43-year-old man with end-stage renal disease requiring hemodialysis for the past 20 years. The patient experienced bilateral knee pain and swelling and was unable to bear weight. Physical examination revealed bilateral quadriceps tendon defect above the patella and loss of active extension. Although plain radiographs of both knees showed no fracture or widening of the joint space, an inferiorly positioned patella was observed. Ultrasonography of the knees revealed a quadriceps tendon defect at the upper edge of each patella, while MR imaging revealed a tear in each quadriceps tendon from the superior poles of the patella. The patient then underwent surgical correction wherein the tendons were repaired using sutures passed through drill holes in the patella. The knees were immobilized with splints for 4 wk before starting physiotherapy. The patient subsequently regained full functional activity within 1 year.     

The efficacy of self-expanding metal stents for palliation of malignant esophageal strictures and fistulas.

OBJECTIVES: Esophageal strictures and esophagorespiratory fistulas are complications of malignant esophageal tumors, which are difficult to manage. The efficacy of self-expanding metal stents (SEMS) for palliation of malignant esophageal strictures and fistulas was investigated prospectively. METHODS: Forty-three SEMS were inserted in 41 patients with malignant esophageal stricture or fistula. Our series included 32 men and nine women, of whom median age was 61.4 years. Twenty nine stents were inserted for stricture, ten for esophago-tracheal fistula, and four esophago-pleural fistula. Stents were inserted endoscopically under fluoroscopic control. RESULTS: SEMS implantation was technically successful in 40 of 41 patients. A second stenting was needed in two patients. Median dysphagia score improved from 3.4 to 1.3. The covered SEMS was succesful in completely sealing 85.7% of the fistulas. Complication occurred in 11 (26.8%) patients. Especially in the case of tumor stenoses in the distal esophagus, complication rate was higher (44%). In total six patients (14.6%) died after stent placement during early postoperative period. Procedure-related mortality was 4.8% (2/41). CONCLUSIONS: We conclude that treatment of malignant esophageal obstructions, including esophagorespiratory fistulas, with SEMS is an alternative palliative procedure. Furthermore SEMS implantation seems more safe in the case of tumor stenoses locating in the middle esophagus.     

One-stage Transthoracic Operation for the Treatment of Right Lung and Liver Hydatid Cysts

In this study we reviewed our experience of hydatid disease of the lung and the liver and discussed the safety and the follow-up results of the one-stage operation. Between 1990 and 2004, 142 patients with pulmonary hydatid disease underwent operation in our clinic. Of these, 27 (19%) patients had cysts located on the dome of the liver, treated with phrenotomy through a right thoracotomy. Hydatid cysts located in the lungs were managed by means of cystotomy. For liver cysts, cystotomy and the inversion of the cavity with sutures was the surgical method of choice, and a drain was left in place. The pulmonary cysts of 12 (8.4%) patients were bilateral and 5 (3.5%) patients had prior surgical treatment of hepatic (n = 1) or pulmonary (n = 4) hydatid cysts. The liver cysts were approached transdiaphragmatically after the lung cysts were excised in 27 (19%) patients. In patients with pulmonary cysts, cystotomy, with or without capitonnage was performed on 123 (86.6%) patients, and wedge resection was performed on 11 (7.7%), segmentectomy was performed on 6 patients (4.2%), and lobectomy was performed on 2 (1.4%) patients. There was no mortality, and only a small number of complications were encountered: empyema in 3, excessive biliary drainage in 2, and bronchopleural fistula in only 1. We suggest that the extraction of pulmonary and hepatic cysts simultaneously through the transthoracic route is a useful and safe surgical technique. This technique also prevents the need for a second operation.     

Studying host genetic background effects on multimorbidity of intestinal cancer development,type 2 diabetes and obesity in response to oral bacterial infection and high‐fat diet using the collaborative cross (CC) lines

BackgroundMultimorbidity of intestinal cancer (IC), type 2 diabetes (T2D) and obesity is a complex set of diseases, affected by environmental and genetic risk factors. High‐fat diet (HFD) and oral bacterial infection play important roles in the etiology of these diseases through inflammation and various biological mechanisms.MethodsTo study the complexity of this multimorbidity, we used the collaborative cross (CC) mouse genetics reference population. We aimed to study the multimorbidity of IC, T2D, and obesity using CC lines, measuring their responses to HFD and oral bacterial infection. The study used 63 mice of both sexes generated from two CC lines (IL557 and IL711). For 12 weeks, experimental mice were maintained on specific dietary regimes combined with co‐infection with oral bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, while control groups were not infected. Body weight (BW) and results of a intraperitoneal glucose tolerance test (IPGTT) were recorded at the end of 12 weeks, after which length and size of the intestines were assessed for polyp counts.ResultsPolyp counts ranged between 2 and 10 per CC line. The combination of HFD and infection significantly reduced (P < .01) the colon polyp size of IL557 females to 2.5 cm², compared to the other groups. Comparing BW gain, IL557 males on HFD gained 18 g, while the females gained 10 g under the same conditions and showed the highest area under curve (AUC) values of 40 000‐45 000 (min mg/dL) in the IPGTT.ConclusionThe results show that mice from different genetic backgrounds respond differently to a high fat diet and oral infection in terms of polyp development and glucose tolerance, and this effect is gender related.     

Effect of clopidogrel pretreatment on angiographic and clinical outcomes in patients undergoing primary percutaneous coronary intervention for ST-elevation acute myocardial infarction

Pretreatment with clopidogrel before elective primary percutaneous coronary intervention (PCI) has been shown to reduce ischemic complications. There are limited data about the value of clopidogrel pretreatment in the setting of PCI for ST-elevation myocardial infarction (STEMI). We aimed to examine the effect of clopidogrel preloading on angiographic and clinical outcomes in patients with STEMI who were treated with PCI. We conducted a prospective registry of all patients treated with primary PCI for STEMI from March 2003 to June 2006. Excluded were patients with cardiogenic shock. For the current analysis, patients (n = 292) were allocated into 2 groups. One group received clopidogrel loading dose before PCI (in the emergency department or coronary care unit, n = 165); the other,immediately after PCI (n = 127). TIMI myocardial perfusion (TMP) grade at the end of PCI and 30-day and 6-month clinical outcomes were assessed. Clinical characteristics were similar among the groups. However, patients pretreated with clopidogrel were more likely to receive aspirin and beta blockers before the current admission. TMP grade 3 occurred in a higher proportion of patients in the clopidogrel pretreatment group than in the no-pretreatment group (85% vs 71%, p = 0.01). Multivariate logistic regression analysis showed that clopidogrel pretreatment was associated with an odds ratio of 2.2 for TMP grade 3 (1.2 to 3.9, p = 0.01). Furthermore, the incidence of reinfarction at 30 days was lower in the pretreatment group (0% vs 3.2%, respectively, p = 0.04). In conclusion, these findings support the early use of clopidogrel in patients with STEMI who are treated with primary PCI.