Laparoscopic omental-cerebellar pedicled graft harvest

The minimally invasive technique has altered our approach to many surgical diseases. Laparoscopic surgery is performed on a variety of abdominal organs. One such organ, the omentum, traditionally has been harvested via a laparotomy. The omental harvest now has been attempted successfully laparoscopically, although usually for reconstructive efforts. Here we describe the first case of a laparoscopic omental-cerebellar pedicled graft harvest.     

Characterization of Trypanosoma evansi type B.

A distinctive feature of Trypanosoma evansi is the possession of a kinetoplast that contains homogeneous DNA minicircles, but lacks DNA maxicircles. Two major sequence variants of the minicircle have been described and here we have sequenced the type B variant and designed a specific PCR test to distinguish it from type A. Further a test based on maxicircles to distinguish T. brucei brucei from T. evansi was designed and evaluated. Using the designed PCR tests, we detected three type B isolates from camel blood samples collected in northern Kenya, more than 20 years after the first isolation of type B. Comparison of minicircle sequences from all four type B isolates shows >96% identity within the group, and 50-60% identity to type A minicircles. Phylogenetic analysis based on minicircle sequences reveals two clusters, one comprising isolates of type A and one of type B, while random amplification of polymorphic DNA show slight polymorphic bands within type B. Most T. evansi isolates analysed were heterozygous at a repetitive coding locus (MORF2). All type B isolates had one genotype designated 3/5 based on the alleles present. Three camel isolates, which had homogenous type A minicircles, lacked the RoTat 1.2 gene, while another five isolates were T. b. brucei, based on the heterogeneity of their minicircles and presence of maxicircles as demonstrated by PCR amplification of the gene for cytochrome oxidase subunit 1. Our results confirm the existence of T. evansi type B isolates, T. b. brucei and existence of T. evansi type A without RoTat 1.2 gene in Kenyan isolates.     

Fas signaling in thyroid carcinomas is diverted from apoptosis to proliferation.

PURPOSE: The death receptor Fas is present in thyroid carcinomas, yet fails to trigger apoptosis. Interestingly, Fas has been reported to be actually overexpressed in papillary thyroid carcinomas, suggesting that it may confer a survival advantage. EXPERIMENTAL DESIGN: We investigated the expression and activation status of Fas pathway mediators in thyroid carcinoma cell lines and tumor specimens. RESULTS: All cell lines tested express Fas-associated death domain, procaspase-8, procaspase-9, and procaspase-3; resistance to Fas-mediated apoptosis could not be attributed to lack of any of these apoptosis mediators. Moreover, Fas death domain mutations were not found in our study. The proteasome inhibitors MG132 and PS-341 (bortezomib, Velcade), which lead to accumulation of the nuclear factor kappaB (NF-kappaB) inhibitor IkappaB, did not sensitize SW579 cells to Fas-mediated apoptosis, suggesting that resistance to Fas-mediated apoptosis is not due to proteasome or NF-kappaB activity. Cross-linking of Fas in vitro induced recruitment of Fas-associated death domain-like interleukin-1beta-converting enzyme inhibitory protein (FLIP) instead of procaspase-8. Inhibition of FLIP expression with a FLIP antisense oligonucleotide resulted in significant sensitization to Fas-mediated apoptosis. Fas cross-linking promoted BrdUrd incorporation; activated the mitogen-activated protein kinase/extracellular signal-regulated kinase kinase/extracellular signal-regulated kinase, NF-kappaB, and activator protein-1 pathways in thyroid carcinoma cells in vitro; and protected cells from tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis. We also found that good prognosis papillary thyroid carcinoma specimens exhibited higher immunoreactivity for cleaved (activated) caspase-8 than poor prognosis tumors. CONCLUSIONS: In thyroid carcinomas, the proteolytic cleavage and activation of caspase-8 depends on the balance between expression levels for procaspase-8 and FLIP and correlates with favorable clinical prognosis. Fas may actually stimulate proliferation and confer a survival advantage to thyroid cancer cells.     

Liver metastases from soft tissue sarcomas

Twenty-three patients with liver metastases from soft tissue sarcoma were reviewed. Patients with metastases to the liver first had poorer survival than those who developed spread to other sites first (P=.0035). The median time from diagnosis of the primary tumor to diagnosis of liver metastases was 14 months; the median time from diagnosis of liver metastases to death was 7 months. The median survival from diagnosis for four patients who underwent liver resection was 54 months compared to 20 months for those who did not undergo resection (NS). Soft tissue sarcomas rarely metastasize to the liver; when this occurs it is usually late in the course of the disease and after it has spread to other sites. The opportunity for successful liver resection is infrequent but may prolong survival. © 1995 Wiley-Liss, Inc.     

Ilioinguinal lymph node dissection

Ilioinguinal node dissection for clinically involved nodes should include in-continuity removal of the inguinal, iliac and obturator lymph nodes. Avoidance of devascularization of the mobilized sartorius muscle and trimming of the skin edges minimize postoperative wound complications.     

An associative analysis of pretreatment effects in gustatory conditioning by amphetamine

Various attempts have been made to account for the fact that pertreatment with some pharmacological agents reduces the ability of such agents to induce conditioned aversion to a flavor. One explanation, based on the concept of tolerance, suggests that pretreatment is effective because it renders the animal less sensitive to direct effects of a given dose of the agent. A second explanation emphasizes the possibility that procedural consequences of pretreatment interfere with associability of flavor and drug effect during conditioning. The second explanation was tested in two experiments. In Experiment I nonreinforced presentations of drug administration cues completely reversed the attenuating effects of amphetamine pretreatment on gustatory conditioning by amphetamine. This finding was replicated and extended in the second experiment which was also designed to eliminate an alternative nonassociative explanation for the results. The principle of associative blocking may explain the effect of pretreatment on subsequent gustatory conditioning by drugs.     

Stereospecific blockage of the alpha adrenergic receptor by substituted 1-aminotetralines.

Certain members of a series of 1-aminotetraline derivatives reversed the epinephrine pressor response in dogs; this effect occurred with the R- but not the S-isomers. Studies with rabbit aortic strips indicated competitive blockade of the alpha adrenergic receptor by the active agents. Receptor protection experiments supported the interpretation that this disruption of receptor function was due to occupancy blockade. This led to a hypothesis defining the steric properties of the alpha receptor and the active conformation of epinephrine at this receptor. However, two hydroxy substituted 1-aminotetralines ans two trihydroxytetrahydrosioquinoline derivatives, which were investigated to support this hypothesis, failed to show the predicted alpha adrenergic agonist activity. It is concluded that the interaction of certain 1-aminotetralines with a stereospecific binding site at the alpha receptor mimics occupancy blockade. However, this binding site is probably not entirely identical with the epinephrine binding site at the alpha receptor. Furthermore, the cyclic tetrahydroisoquinoline derivatives do not represent the active conformation of epinephrine at the receptor.