Laparoscopic sigmoid colectomy: Total laparoscopic approach

Laparoscopic surgery seems set to make a significant impact on the practice of colorectal surgery. However, to date, the majority of surgeons have used a technique of laparoscopic assistance whereby initial laparoscopic mobilization of the bowel is followed by extracorporeal mesenteric and bowel division and subsequent restoration of bowel continuity. This report describes a technique of totally laparoscopic left-sided colonic resection, transanal specimen delivery, and intracorporeal colorectal anastomosis. The technique employed is described in detail and the indications and controversies surrounding such an approach are discussed.     

Stable Anticonvulsant Action of Benzodiazepines During Development in Rats

Abstract— The anticonvulsant action of midazolam and clonazepam was studied in 168 immature rats in three age groups (12, 18 and 25 days old). Epileptic after-discharges of the spike-and-wave type accompanied by clonic seizures of facial and forelimb muscles induced by stimulation of sensorimotor cortex were used as a model. The solvent used for clonazepam exhibited a tendency to anticonvulsant action in 12-day-old rats. On the contrary, a proconvulsant action was seen in 25-day-old animals. The action of both benzodiazepines was identical and did not change substantially during development. The highest dose used (1 mg kg^?1, i.p.) shortened the duration of epileptic after-discharges, the two lower doses (0·1 and 0·02 mg kg^?1, i.p.) suppressed the progressive prolongation with repeated stimulations seen under control conditions. Motor correlates of stimulation remained practically uninfluenced by the two benzodiazepines, myoclonic seizures accompanying epileptic after-discharges were attenuated by the highest dose of both drugs.     

Septo-optic dysplasia: MR imaging

Septo-optic dysplasia is the diagnosis when optic nerve hypoplasia is seen in conjunction with dysgenesis of the septum pellucidum. Nearly two-thirds of these patients have hypothalamic-pituitary dysfunction, and half have schizencephaly. The disorder is difficult to classify because of the diversity of clinical and pathologic manifestations. Magnetic resonance images of 11 patients with clinical and radiographic evidence of septo-optic dysplasia were reviewed retrospectively. The "syndrome" appears to include two subsets of patients whose abnormalities have different embryogenesis and neuropathologic findings. The existence of these two subsets helps to explain the diversity of the clinical and radiologic findings.     

Relative Immunogenicity and Tolerogenicity of Individual Regions or Segments of the MHC

Mixed lymphocyte culture (MIX) reactivity, induction of cytotoxicity in vitro, survival of skin allografts, and induction of neonatal transplantation tolerance were compared in mice of the strain combinations differing in the entire H-2 complex or in individual segments of it. The results showed that antigenic products of the K end of the H-2 complex were more immunogenic and also more resistant to tolerance induction than the products of the D end of H-2. I-region products that elicited transplantation reactions of variable strength, depending on the detection system, were relatively easier to overcome in tolerance induction and could, at least in some combinations, contribute to tolerance induction across the barrier represented by the products of the K region of the H-2 complex.     

Apolipoprotein D is down-regulated during malignant transformation of neurofibromas

Apolipoprotein D (apoD) expression was studied in nonneoplastic peripheral nerve, neurofibromas (NFs), and malignant peripheral nerve sheath tumors (MPNSTs) by quantitative polymerase chain reaction, in situ hybridization, and immunohistochemistry. Multiplex quantitative polymerase chain reaction for messenger RNA was performed on a series of formalin-fixed and paraffin-embedded specimens that included 9 MPNSTs, 12 NFs, and 4 normal peripheral nerves. The average apoD expression was 108-fold decreased (DeltaCt = -7.3) in the MPNSTs compared with the NFs (P < .05). ApoD expression levels were 3.0-fold elevated (DeltaCt = 1.7) in the NFs compared with nonneoplastic peripheral nerve (P < .05). In situ hybridization for apoD RNA was performed on a separate series of 10 cases in which each microscopic section included both MPNST and the NF from which it arose. These studies confirmed elevated apoD expression in NFs compared with MPNSTs and demonstrated that this expression was variable among individual cells within the NFs. Differential expression by immunohistochemistry could only be demonstrated in selected areas, most likely because apoD protein is a small molecule that is secreted out of the cell into the extracellular space and plasma. ApoD expression initially increases a small amount with the formation of NFs from nonneoplastic peripheral nerve and subsequently decreases markedly as NFs transform into MPNSTs. This expression pattern may serve as a marker for cell cycle inhibition during peripheral nerve tumorigenesis.     

A p74 common gamma receptor chain isoform facilitates IL-2 and IL-15 responses by the myelomonocytic cell line Tf-1beta2

Functional forms of the IL-2, IL-4, IL-7, IL-9, and IL-15 receptors require the gamma c receptor component. We have described previously a myeloid cell line called Tf-1beta, which binds IL-2 with intermediate-affinity and proliferates in response to IL-2. In this study, we characterize gamma c expression on Tf-1beta2 cells, a derivative of Tf-1beta cells stimulated exclusively with IL-2. Although Tf-1beta2 cells bind IL-2 with intermediate-affinity and proliferate in response to IL-2, this cell line does not express the p64 gamma c chain at the protein level. This result was surprising because prior studies suggest these cells should not be expected to proliferate in response to IL-2 or IL-15 in the absence of the p64 gamma c chain. A p74 protein was detected by western blot following immunoprecipitation with an anti-gamma c polyclonal antibody, and a p74 protein was identified consistently in complex with IL-2 and IL-15 on these cells. However, the gamma c gene in these Tf-1beta2 cells shows no evidence of mutation by sequence analysis. Furthermore, inhibition of glycosylation of these Tf-1beta2 cells by tunicamycin treatment yields a standard 39-kDa molecule recognized on western blot with anti-gamma c antibody, as seen for the standard 64-kDa isoform of gamma c. These results demonstrate that a 74-kDa gamma c receptor isoform was involved in the response of the Tf-1beta2 cells to cytokines which normally interact with the 64-kDa gamma c chain.