In vitro release and In vivo biocompatibility studies of biomimetic multilayered alginate-chitosan/β-TCP scaffold for osteochondral tissue

Biomimetic three-layered monolithic scaffold (TLS) intended for the treatment of osteocondral defects was prepared by using alginate, chitosan and β-tricalcium phosphate (β-TCP) to study drug release behavior of the alternative drug delivery system and to investigate the therapeutic efficacy of the scaffold. Dexamethasone sodium phosphate (Dex) as a model drug was incorporated into the scaffold by solvent sorption method and in vitro release studies were conducted. In addition, the scaffold was implanted into the defects formed in the trochlea of Sprague–Dawley rats to assess the healing potential of the TLS on the osteochondral defect against reference Maioregen® comparatively. The release studies showed that after an initial burst at 3rd h, dexamethasone is released slowly during a 72-h period. In vivo studies indicated that the TLS has good tissue biocompatibility and biodegradation rate and showed better results during osteochondral healing process compared to the reference. All results demonstrated that the alginate-chitosan/β-TCP scaffold could be evaluated as a good candidate for osteochondral tissue applications.     

Encapsulation of insulin in chitosan-coated alginate beads: oral therapeutic peptide delivery

Insulin was encapsulated in calcium alginate beads coated with chitosan. Its release from alginate-chitosan and alginate-chitosan-glutaraldehyde beads was studied in artificial gastric (pH 1.2) and intestinal (pH 7.5) fluids. By comparing the release amounts, the ionic interaction between alginate-chitosan matrix with the medium pH's, intestinal fluid was found to be the better. The degradation of released insulin was also searched, even after 6 h incubation, the beads remained stable and the undegraded insulin seemed to be sufficient for the physiological conditions. Consequently, it can be said that the system can be offered for oral delivery of the therapeutic peptide drug insulin.     

Which antimuscarinic agents used in the treatment of overactive bladder increase heart rate? a prospective randomized clinical trial

International Urology and Nephrology - To compare the heart rate increase side effect of different antimuscarinic drugs used in overactive bladder (OAB). Overall 341 patients were consecutively...     

A simple position to provide better imaging of upper ureteral stones close to the crista iliaca during extracorporeal shock wave lithotripsy using the Siemens Lithostar

OBJECTIVE: The fluoroscopic image from the second plan (oblique) tube of an upper ureteral stone close to the crista iliaca may be superimposed on the pelvic bones during SWL using the Siemens Lithostar with the patient in the prone position. This creates difficulty in imaging and targeting of the stone and can necessitate using ureteral catheters before treatment and/or intravenous contrast injection during SWL. We describe a very simple, yet effective method for easier visualization of the stone under this circumstance. METHODS: Between March 1992 and February 2003, we treated 1561 patients with ureteral stones by SWL with the Siemens Lithostar. The stones were localized in the upper ureter in 841. The image of the stone from the second plan (oblique) tube was superimposed on the pelvic bones in 221 in whom visualization of the stone was hardly possible with the standard prone position. By simply rotating the patient 180 degrees on the table, the superimposition of the image of the stone on the pelvic bone was obviated. This resulted in easier and better imaging of the stone during SWL. It also allowed for a clear and superior image to the treating physician during SWL. The energy and shock waves, utilization of anesthesia, number of treatment sessions, auxiliary measures, and complications were noted. Stone load was recorded in square centimeters (cm(2)). Patients were evaluated by intravenous urogram or KUB and ultrasonography when stone-free or CIRF (nonobstructive and noninfectious insignificant fragments < or =4mm) status was noted at the fluoroscopic control 2 to 4 weeks after the last session. Final CIRF decision was made 10-12 weeks after the last session. SWL was regarded as failure if no fragmentation was noted after the 3rd session. Therapy was continued if fragmentation was noted. RESULTS: The median age was 40 (range 5-85). The mean stone burden was 0.8 (range 0.24-2.9) cm(2). No indwelling ureteral stents were placed in any patients before and during treatment. The mean number of shock waves and energy used for the entire patient population was 2007 and 17.5kV, respectively. The median and average treatment session was 1 and 1.7, respectively. A total of 196 patients (89%) were rendered stone-free. Clinically insignificant residual fragments were present in 18 (8%). SWL was unsuccessful in 7 (3%) patients. These stones were removed by ureterorenoscopy. Intravenous contrast administration was not used to facilitate stone targeting during SWL. Anesthesia, in the form of analgesic sedation, was used in 7 (3%) patients. We did not observe any complications and adverse effects. CONCLUSIONS: The technique described hereby does not have an affect on coupling; it only provides a superior image of the stone to the treating physician. We advocate its application in all patients with upper ureteral stones close to the crista iliaca when the fluoroscopic image of the stone from the second plan (oblique) tube is superimposed on pelvic bones during SWL in prone position.     

Computed tomography findings in 66 patients with malignant pleural mesothelioma due to environmental exposure to asbestos

We aimed to investigate the computed tomography (CT) findings of malignant pleural mesothelioma (MPM) caused by environmental asbestos exposure. We retrospectively reviewed CT scans of 66 patients, which were performed before any invasive procedure was done. Pleural effusion (80.3%), pleural thickening (77.2%), volume contraction (37.9%), involvement of mediastinal pleura (31.8%) and interlobar fissure (28.8%) were the most common CT findings of MPM. Although none of these findings are pathognomonic for MPM, they may provide valuable clues for the differential diagnosis, at least in patients with a history of asbestos exposure.     

Effect of hepatic dysfunction on oral cyclosporin pharmacokinetics in marrow transplant patients

The effect of hepatic dysfunction, defined as abnormal serum bilirubin level, on oral cyclosporin (CSP) pharmacokinetics was examined in 28 marrow transplant patients who received CSP for prophylaxis of graft-v- host disease. Serum CSP concentrations were measured by radioimmunoassay. Forty-one concentration-time courses were studied, divided among patients with no (less than 1.2 mg/dL), mild (1.2 to 2.0 mg/dL), and moderate (2.0 to 5.0 mg/dL) hepatic dysfunction. CSP elimination, as determined by elimination rate constant and clearance, was delayed in patients with moderate hepatic dysfunction compared to those with no hepatic dysfunction (P less than .05). The volume of distribution, lag time for absorption, maximum serum concentration, and time at which the maximum concentration was achieved was not affected by hepatic function. These data indicate that patients with moderate hepatic dysfunction have delayed CSP or CSP metabolite elimination and may be at higher risk for developing CSP-related toxicity.     

Preliminary findings for preemptive analgesia with inhaled morphine: efficacy in septoplasty and septorhinoplasty cases.

OBJECTIVE: The aim of this study was to assess the efficacy of inhaled morphine for preemptive analgesia in patients who undergo septoplasty or septorhinoplasty. STUDY PLAN AND METHODS: Eighty ASA I-II patients scheduled for septoplasty or septorhinoplasty were recruited and randomly divided into 2 groups that received different treatments 10 minutes prior to induction. The preemptive analgesia group (Group P, n = 40) received 65 mug kg(-1) morphine sulphate (a 3-mL volume) via an oral nebulizer, and the control group (Group C, n = 40) received 3 mL 0.9% sodium chloride (physiological saline) via the same type of nebulizer. Blood pressure, oxygen saturation, heart rate, time to first requirement for analgesia, and occurrence of nausea/vomiting were recorded. RESULTS: There were no significant differences between Groups P and C with respect to age, body weight, sex distribution, or duration of surgery. There was also no significant difference between the group frequencies of postoperative nausea/vomiting. The time to first requirement for analgesia was significantly longer in Group P than Group C. CONCLUSION: The results of this preliminary study suggest that a single dose of inhaled morphine administered preemptively prior to septoplasty or septorhinoplasty provides effective postoperative analgesia. EBM rating: B-3b.     

Modified experimental mild traumatic brain injury model

BACKGROUND: Experimental models of traumatic brain injury (TBI), using a variety of techniques and species, have been devised with the aim of producing repeatable lesions resembling those found in head injuries. There are various TBI models mentioned in the literature. In experimental head trauma models, emphasis has been placed on the severe head injuries. There are only a few models developed to study mild traumatic brain injury (MTBI). In fact, MTBI is as important a problem as severe head injuries for neurosurgeons. METHODS: Fifty-six male Sprague-Dawley rats were subjected to MTBI with a weight-drop device, which was described by Marmarou et al. The said model was used in its original form as well as in modified forms by employing different weights dropped from the same height. Animals were divided into four groups of 14 rats as follows: Group I (n=14), head injury was induced using 450 g-1 m weight-height impact; Group II (n=14), head injury was induced using 350 g-l m weight-height impact; Group III (n=14), head injury was induced using 300 g-1 m weight-height impact; Group IV (n=14), control group, no injury was applied. Animals were evaluated neurologically, physiologically, electrophysiologically, and histopathologically. RESULTS: Group I and II animals (450 and 350 g-1m weight-height impact, respectively) showed the symptoms of severe head injury, whereas Group III animals (300 g-l m) showed more MTBI symptoms. CONCLUSION: We recommend the application of the modified MTBI model used for group III (300 g-l m weight-height impact) as the most appropriate and the simplest model for future MTBI studies.     

Dosimetric comparison of vaginal vault brachytherapy vs applicator-guided stereotactic body radiotherapy with volumetric modulated arc therapy and helical tomotherapy for endometrium cancer patients

We performed this dosimetric study to compare a nonstandard volumetric modulated arc therapy (VMAT) and helical tomotherapy (HT) techniques with high-dose rate (HDR) brachytherapy (BRT) plan of vaginal vault in patients with postoperative endometrial cancer (EC). Twelve postoperative patients with early stage EC were included in this study. Three plans were performed for each patient; dosimetric and radiobiological comparisons were made using dose-volume histograms and equivalent dose for determining the planning target volume (PTV) coverages in brachytherapy and external beam radiotherapy, and organs-at-risk (OARs) doses between three different delivery techniques. All the plans achieved adequate dose coverage for PTV; however, the VMAT plan yielded better dose conformity, and the HT plan showed better homogeneity for target volume. With respect to the OARs, the bladder D_2cc was significantly lower in the BRT plan than in the VMAT and HT plans, with the highest bladder D_2cc value being observed in the HT plan. However, no difference was observed in the rectum D_2cc of the three plans. Other major advantages of the BRT plan over the VMAT and HT plans were the relatively lower body integral doses and femoral head doses as well as the fact that the integral doses were significantly lower in the BRT plan than in the VMAT and HT plans. This is the first dosimetric comparison of vaginal vault treatment for EC with BRT, VMAT, and HT plans. Our analyses showed the feasibility of stereotactic body radiotherapy technique as an alternative to HDR-BRT for postoperative management of EC patients.