Bone quality in swine composite tissue allografts: effects of combination immunotherapy

BACKGROUND: Tacrolimus (FK506)/mycophenolate mofetil (MMF)/prednisone combination immunosuppression therapy has been found to effectively prevent composite tissue allograft (CTA) rejection with minimal toxicity in a preclinical porcine model. These findings have been reproduced in 24 human hands transplanted in 18 patients. In CTAs containing bone, adequate bone quality and healing are essential for long-term functional success. The purpose of this study was to determine the effect FK506/MMF/prednisone immunotherapy has on bone quality and healing. METHODS: Forelimb CTA-flaps were transplanted in nine pigs. Recipient animals received FK506/MMF/prednisone therapy for 3 months. Bone quality was studied pre- and posttransplant by measuring acoustic velocity and density and by calculating elastic coefficients. Additional bone quality analyses were performed on unoperated limbs, and in bone grafts from two pigs that had autograft procedures performed. Bone healing was assessed using radiographic analysis. RESULTS: Three animals were lost to immunosuppression-related complications before the endpoint of the study. The bone component of all six CTA-flaps showed normal healing. Although results of the bone density measurements were not significantly different when comparing pre- to posttransplant values, acoustic velocity and elastic coefficient measurements showed a significant decrease posttransplant indicating a decrease in bone quality. CONCLUSIONS: FK506/MMF/prednisone combination therapy prevented rejection, did not adversely affect bone quality, and showed normal bone healing. The transplant procedure itself decreased bone quality more than the immunosuppression regimen did over the observation period in this study. Based on these findings, we conclude to prevent CTA failure it is important to monitor bone quality posttransplant.     

Late‐phase ischemic preconditioning in skeletal muscle: is the phenomenon protective?

Reports in the literature on the effectiveness of late-phase Ischemic preconditioning (IPC) in skeletal muscle are controversial. The purpose of this study was to determine in the same muscle flap model the effectiveness of various IPC protocols in inducing late-phase protection. Rat latissimus dorsi muscle (LDM) flaps were preconditioned with either 30 or 60 min of total ischemia, divided as follows: single cycles of either 30 or 60 min, two cycles of 15 or 30 min, and three cycles of 10 or 20 min. Ischemia cycles were separated by 10 min of reperfusion. A day after IPC, flaps were elevated and challenged with 4 h of ischemia. Three days later, flaps were assessed for viability. We found that IPC protocols of different total durations and comprised of two or three cycles of ischemia elicited a protective effect against necrosis. We conclude that IPC induces late-phase protection against necrosis in skeletal muscle, and that the protection requires more than one ischemia/reperfusion cycle.     

Long-term histopathologic and morphologic changes after thermal endometrial ablation

STUDY OBJECTIVE: To outline long-term histologic features of endometrial ablation. DESIGN: Prospective longitudinal study (Canadian Task Force classification II-3). SETTING: Tertiary-care teaching hospital. PATIENTS: Twenty-six patients. INTERVENTION: Thermal ablation followed by second-look office hysteroscopy with endometrial biopsy. MEASUREMENTS AND MAIN RESULTS: Mean follow-up time to second-look hysteroscopy after ablation was 33.4 +/- 2,1 months. Complete atrophy, partial adhesions or obliteration of the cavity, and fibrosis were observed at second-look hysteroscopy. Whereas all random biopsies were normal before ablation, biopsies after ablation revealed diminished endometrial glands with necrosis and scarring. The number of endometrial glands was not correlated with amount of bleeding or menstrual pattern. No premalignant or malignant lesions were found after ablation. CONCLUSION: Although efficacy of endometrial ablation is related to initial thermal destruction and correlated with postablation hysteroscopic and histologic findings, endometrial regrowth is an expected development, not a failure of ablation.     

Vancomycin versus teicoplanin in the therapy of experimental methicillin-resistant Staphylococcus aureus (MRSA) meningitis

The aim of this study was to compare the antibacterial activity of teicoplanin and vancomycin in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) meningitis using a rabbit meningitis model. The MRSA strain ATCC 43300 was used to infect the rabbits. The vancomycin group received 20 mg/kg vancomycin every 12h (q12h), the teicoplanin group received 6 mg/kg teicoplanin q12h and the control group did not receive any treatment. Drug levels were measured using a bioassay technique. Bacterial counts in the treatment groups were significantly lower (P<0.05) than those of the control group at 12 h and 24 h after treatment. When the treatment groups were compared, the bacterial counts after 12 h or 24 h of treatment were similar (P>0.05). These data suggest that the antibacterial activity of vancomycin and teicoplanin are similar in experimental MRSA meningitis of rabbits.     

The effect of the menstrual cycle on the optic nerve head analysis of migrainous women

PURPOSE: To determine the effect of the menstrual cycle on the optic nerve head topographic analysis of normally menstruating migrainous women. MATERIAL AND METHODS: Randomly selected one eye of 44 migrainous and 49 healthy control women with regular menstrual cycles were included in the study. All subjects underwent complete ocular examination. Optic nervehead topographic analysis were performed using a confocal scanning laser ophthalmoscope, HRT II (Heidelberg Retinal Tomograph II, software version 1.6;Heidelberg Engineering, Heidelberg, Germany). They were repeated for two times during the menstrual cycle: in follicular phase (7th to 10th day of the cycle) and in the luteal phase (days 3 to 4 before the menstrual bleeding). Serum estradiol, progesterone, and luteinizing hormone measurements were repeated at each menstrual phase. Results: The mean age of migrainous and control subjects were 31.5 + 5.1 years and 33.4 +/- 3.7 years, respectively (P > 0.05). Their mean disc areas were 2.26 +/- 0.46 mm(2) and 1.95 +/- 0.39 mm(2), respectively(P < 0.05). Control subjects did not demonstrate any difference in the disc topography (P > 0.05). The parameter rim volume decreased, while the parameters cup volume and cup shape measure increased significantly in the luteal phase of the migrainous women (all P values <0.05). Mean intraocular pressure of the migrainous women decreased significantly in luteal phase (P < 0.05). CONCLUSION: Significant differences exist in the optic rim and cup parameters during the menstrual cycle of the migrainous women. Further clinical trials on ocular blood flow changes during the menstrual cycle of the migrainous women may highlight the role of sex steroids in the optic nerve head of the migrainous women.     

Percutaneous brachial artery catheterization

We describe modifications and suggestions for safer percutaneous catheterization of the brachial artery based in part on the anatomy of the axillary-brachial artery and surrounding nerves of the brachial plexus. The brachial artery approach should be nearly as safe as the femoral artery approach for percutaneous catheterization and should not be avoided if the femoral arteries cannot be used.     

Total intravenous anesthesia versus single breath technique and anesthesia maintenance with sevoflurane for bariatric operations

Background: The choice of anesthetic technique for general anesthesia in morbidly obese patients remains controversial. We aimed to compare blood gases, recovery and hemodynamic parameters using TIVA and sevoflurane anesthesia in bariatric surgery. Methods: The study was performed with permission of the ethics committee.We studied 40 morbidly obese patients allocated to 2 groups. The total I.V. anesthesia (TIVA) group was named Group T, and the sevoflurane group was named Group S. In Group T, anesthesia induction was achieved with propofol. In Group S, anesthesia induction was achieved by sevoflurane with single breath technique, with maintenance provided with 1-2% volume sevoflurane. Student t, Chi square and ANOVA tests were used for data analysis; p-value <0.05 was considered statistically significant. Results: There was no significant difference between the 2 groups in demographic data, blood gas values and recovery characteristic. Hemodynamic values were significantly lower in Group T than Group S, during and after the operative period. Conclusion: While sevoflurane induction and maintenance is a suitable anesthetic modality for obese patients, TIVA can be applied easily in those patients possessing no extra risk factors other than morbid obesity.