Five year retrospective analysis of the autogenous tendon graft procedure for primary ankle repair and ankle stabilization

A 5-year review regarding the autogenous tendon graft procedure using the peroneal tendons to repair acute ruptures of the anterior talofibular and calcaneofibular ligaments, and to correct chronic, unstable ankles is presented. The autogenous tendon graft has been used to limit excessive subtalar inversion in feet with mild-to-moderate calcaneal varus causing an unstable foot and ankle. This is achieved by placing the tendon graft perpendicular or distal to the vertical axis of the lateral malleolus at the calcaneofibular ligament site.     

Dedifferentiated chondrosarcoma of the rib with a malignant mesenchymomatous component: An autopsy case report

A rare variant of dedifferentiated chondrosarcoma wlth malignant mesenchymomatous component in a 57-year-old male is reported. The patient presented with a posterior mediastinal mass arising from the left eighth and ninth ribs showing well differentiated, low-grade chondrosarcoma. Five years later, local recurrence occurred and an excised specimen also showed the same histological features as the primary tumor. Another 6 years later, the tumor recurred and metastasized to the multiple organs, the patient dying 4 months later. Autopsy revealed that the recurrent and metastatic tumors showed malignant mesenchymomatous 'dedifferentiation' of chondrosarcoma composed of rhab domyosarcoma, angiosarcoma, chondrosarcoma, osteosarcoma, and leiomyosarcoma, in addition to fibrosarcomatous areas. Although the less differentiated component of dedifferentiated chondrosarcoma usually shows the histological features of malignant fibrous histiocytoma and fibrosarcoma, multilineage differentiation can occur in that component. The phenomenon of 'dedifferentiation' in chondrosarcoma and the relationship to and distinction from malignant mesenchymoma of soft tissue and bone are discussed.     

Interaural phase-sensitive units in the inferior colliculus of the unanesthetized rabbit: effects of changing frequency

We studied the interaural phase sensitivity of 85 units in the inferior colliculus (IC) of the unanesthetized rabbit. We assessed this sensitivity at several frequencies within each unit's responsive range. The interaural phase disparity was varied by delivering tones that differed by 1 Hz to the two ears, resulting in a 1-Hz binaural beat. We analyzed each unit's response to different frequencies by calculating four measures: characteristic delay (CD), characteristic phase (CP), composite peak delay, and mean peak delay. We estimated the CD and CP from the slope and phase intercept, respectively, of the regression line fitted to a plot of the mean interaural phase against stimulating frequency. The composite peak delay was estimated from the peak of a composite delay curve. This was generated by replotting the response to changes in interaural phase, as a function of the equivalent interaural delay and averaging the resultant interaural delay curves. The composite delay curve reflects the unit's average response to interaural delays across frequencies. Last, we calculated a mean peak delay, derived by converting the mean interaural phase of the response at each frequency to an equivalent delay and then averaging these delays. Interaural phase sensitivity was observed to frequencies as high as 2,150 Hz. However, the majority of units showed such sensitivity below 1,500 Hz. For most units, the interaural delay curves measured at several frequencies coincided near the peak discharge. This result is consistent with a neural model, where excitatory inputs from each ear converge upon a binaural cell, evoking maximum discharge only when the two inputs arrive simultaneously. As a first approximation, our data fit this model, indicating that IC neurons can act like coincidence detectors or cross-correlators. The distributions of CD, composite peak delay, and mean peak delay showed that most units preferred ipsilateral stimulus delays, which in the natural situation corresponds to sounds emanating from the contralateral field. Moreover, most units preferred delays that were within the estimated physiological range of the rabbit. These results support the viewpoint that neurons in the IC participate in sound localization. The distributions of CP and CD differ substantially from those found in the IC of the anesthetized cat. These differences may reflect species differences, the effects of anesthesia, or a difference in the population of units sampled. For each unit, we assessed the linearity of the plot of mean interaural phase against frequency of stimulation using a chi 2 method. For most units the plots were significantly nonlinear.(ABSTRACT TRUNCATED AT 400 WORDS)     

Acoustic Cues for Sound Source Distance and Azimuth in Rabbits, a Racquetball and a Rigid Spherical Model

There are numerous studies measuring the transfer functions representing signal transformation between a source and each ear canal, i.e., the head-related transfer functions (HRTFs), for various species. However, only a handful of these address the effects of sound source distance on HRTFs. This is the first study of HRTFs in the rabbit where the emphasis is on the effects of sound source distance and azimuth on HRTFs. With the rabbit placed in an anechoic chamber, we made acoustic measurements with miniature microphones placed deep in each ear canal to a sound source at different positions (10–160 cm distance, ±150° azimuth). The sound was a logarithmically swept broadband chirp. For comparisons, we also obtained the HRTFs from a racquetball and a computational model for a rigid sphere. We found that (1) the spectral shape of the HRTF in each ear changed with sound source location; (2) interaural level difference (ILD) increased with decreasing distance and with increasing frequency. Furthermore, ILDs can be substantial even at low frequencies when distance is close; and (3) interaural time difference (ITD) decreased with decreasing distance and generally increased with decreasing frequency. The observations in the rabbit were reproduced, in general, by those in the racquetball, albeit greater in magnitude in the rabbit. In the sphere model, the results were partly similar and partly different than those in the racquetball and the rabbit. These findings refute the common notions that ILD is negligible at low frequencies and that ITD is constant across frequency. These misconceptions became evident when distance-dependent changes were examined.     

LC–MS analysis of saponins of Achyranthes root in the Japanese market

Journal of Natural Medicines - LC–MS analyses of saponin fractions of Achyranthes roots in the Japanese market revealed that there were three patterns for the saponin fraction of their water...     

Revisional bariatric surgery: perioperative morbidity is determined by type of procedure

Background

Revisional bariatric procedures are on the rise. The higher complexity of these procedures has been reported to lead to increased risk of complications. The objective of our study was to compare the perioperative risk profile of revisional bariatric surgery with primary bariatric surgery in our experience.

Methods

A prospectively maintained database of all patients undergoing bariatric surgery by three fellowship-trained bariatric surgeons from June 2005 to January 2013 at a center of excellence was reviewed. Patient demographics, type of initial and revisional operation, number of prior gastric surgeries, indications for revision, postoperative morbidity and mortality, length of stay, 30-day readmissions, and reoperations were recorded. These outcomes were compared between revisional and primary procedures by the Mann–Whitney or Chi square tests.

Results

Of 1,556 patients undergoing bariatric surgery, 102 patients (6.5 %) underwent revisional procedures during the study period. Indications for revisions included inadequate weight loss in 67, failed fundoplications with recurrent gastroesophageal reflux disease in 29, and other in 6 cases. Revisional bariatric procedures belonged into four categories: band to sleeve gastrectomy (n = 23), band to Roux-en-Y gastric bypass (n = 25), fundoplication to bypass (n = 29), and other (n = 25). Revisional procedures were associated with higher rates of readmissions and overall morbidity but no differences in leak rates and mortality compared with primary procedures. Band revisions had similar length of stay with primary procedures and had fewer complications compared with other revisions. Patients undergoing fundoplication to bypass revisions were older, had a higher number of prior gastric procedures, and the highest morbidity (40 %) and reoperation (20 %) rates.

Conclusions

In experienced hands, many revisional bariatric procedures can be accomplished safely, with excellent perioperative outcomes that are similar to primary procedures. As the complexity of the revisional procedure and number of prior surgeries increases, however, so does the perioperative morbidity, with fundoplication revisions to gastric bypass representing the highest risk group.     

Identification of an Anti–Integrin αvβ6 Autoantibody in Patients With Ulcerative Colitis

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Colorectal cancer 2000. Education and screening are essential if outcomes are to improve

Mortality from colorectal cancer is less threatening than it was 10 years ago, but this cancer is still a leading cause of death in the United States and the world. Careful history taking, education about the importance of a high-fiber, low-fat diet and exercise, and regular screening are important steps in improving outcomes. For the busy primary care physician and the equally busy patient, prevention can become a low priority. However, the benefits of early preventive intervention are clearly worth the effort.