Anaesthetic management during awake craniotomy in a 12-year-old boy

We present our approach to the preoperative preparation and anaesthetic management for awake craniotomy in a 12-year-old boy. Management included conscious sedation with a propofol infusion plus local anaesthetic infiltration of the scalp, periosteum, and dura. The complications which may be encountered during such procedures and their treatments are reviewed.     

A Pilot Feasibility Study of a Rare Skin Tumor Database

BACKGROUND: In the United States melanoma is the only individually reported skin cancer. There are no large state or national registries for nonmelanoma skin cancer. Nevertheless, rare, that is, nonmelanoma, nonepithelial, tumors can also be locally aggressive and metastasize. OBJECTIVES: This study's purpose was to demonstrate that Mohs surgeons can share data to create a rare skin tumor database. This database may serve as a model for a nationwide database. MATERIALS AND METHODS: We retrospectively reviewed the surgery logs of five Mohs surgery practices in the Houston, Texas, area for rare-nonmelanoma, nonepithelial-skin cancers. A total of 42,279 biopsy-proven cancers of the skin treated with Mohs micrographic surgery were reviewed. Tumor data including type, prevalence, year of treatment, and the treating Mohs surgeon(s) were compiled and analyzed. RESULTS: Forty-three types of rare tumors were identified. A total of 317 rare tumors were treated. No practice saw more than 28 rare tumor types. Atypical fibroxanthoma was the rare tumor most often treated. CONCLUSIONS: Colleagues can cooperate to create a database of rare tumors removed by Mohs micrographic surgery. A range of tumors greater than that seen in any single practice is now available for study. This should provide the impetus for a nationwide rare skin tumor database.     

Optimization and validation of an ischemic wound model

Localized tissue ischemia is a key factor in the development and poor prognosis of chronic wounds. Currently, there are no standardized animal models that provide sufficient tissue to evaluate the effect of modalities that may induce angiogenesis, and in vitro models of angiogenesis do not mimic the complexity of the ischemic wound bed. Therefore, we set out to develop a reproducible ischemic model for use in wound-healing studies. Male Sprague-Dawley rats underwent creation of dorsal bipedicle skin flaps with centrally located excisional wounds. Oxygen tension, wound-breaking strength, wound area, lactate, and wound vascular endothelial growth factor (VEGF) were compared in flaps measuring 2.5 and 2.0 x 11 cm with and without an underlying silicone sheet. We found that the center of the 2.0 cm flap with silicone remains in the critically ischemic range up to 14 days without tissue necrosis (33+/-4 vs. 49+/-6 mmHg in controls). Wound healing and breaking strength were significantly impaired and tissue lactate from the center of this flap was 2.9 times greater than tissue from either nonischemic controls and 2.5 cm flap (0.23+/-0.05 mg/dL/mg sample vs. 0.09+/-0.02 and 0.08+/-0.02, respectively). Vascular endothelial growth factor was 2 times greater than the nonischemic control. This ischemic wound model is relatively inexpensive, easy to perform, reproducible, and reliable. The excisional wounds provide sufficient tissue for biochemical and histologic analysis, and are amenable to the evaluation of topical and systemic therapies that may induce angiogenesis or improve wound healing.     

Random coil conformation for extended polyglutamine stretches in aqueous soluble monomeric peptides

Several neurodegenerative diseases have been found to be strongly associated with proteins containing a polyglutamine stretch which is greatly expanded from approximately 20 glutamines in normal individuals to more than 40 in affected individuals. A conformational change in the expanded polyglutamine stretch has been suggested to form the molecular basis for disease onset. Model peptides containing polyglutamine tend to aggregate and become insoluble. We have synthesized readily water-soluble monomeric peptides by flanking polyglutamine stretches with sequences rich in alanine and lysine. Circular dichroism measurements show that polyglutamine stretches of length 9 or 17 adopt a random coil configuration in aqueous solution. We think that in the disease-associated peptides for normal individuals the stretches of ～20 glutamines are in a random coil conformation, whereas in affected individuals the polyglutamine stretch may be in some other conformation. Our method to design soluble monomeric peptides containing extended polyglutamine stretches may be generally useful in studying other highly aggregating peptides.     

Chronic Nephropathy and Renal Carcinogenicity of o-Benzyl-p-chlorophenol in F344/N Rats and B6C3F1 Mice

o-Benzyl-p-chlorophenol, an aryl halide biocide, was evaluatedin male and female F344/N rats and B6C3F₁ mice in a series ofsubchronic and 2-year toxicity and carcinogenicity studies.Kidney was the primary target of toxicity in the 13-week gavagestudies in rats and mice, with increased nephropathy noted aslow as 240 mg/kg in male rats. Considering the nephropathy tobe dose-limiting, the chronic (2-year) study was conducted atlower doses (male rats: 30, 60, or 120 mg/kg; female rats: 60,120, or 240 mg/kg; male and female mice: 120, 240, or 480 mg/kg;in corn oil; n=50/group). Survival and body weights of dosedrats were similar to controls in the 2-year study. Survivalof high-dose male and female mice, and body weights of all dosedmale and mid- and high-dose female mice, were lower than controls.The incidence and severity of nephropathy increased with doseand length of treatment in both rats and mice. There was anincreased incidence of renal tubule adenomas or carcinomas inboth the mid- and high-dose male mice. Despite similar evidenceof nephropathy, however, there were no increased incidencesof neoplasms in female mice or in male or female rats. Thisstudy suggests therefore that while nephrotoxicity may havebeen a necessary component, factors other than the marked nephrotoxicityof o-benzyl-p-chloro-phenol were critical to the developmentof renal carcinogenesis induced in only male mice.     

Influence of Viral Infections on Body Weight, Survival, and Tumor Prevalence of B6C3F1 (C57BL/6N ? C3H/HeN) Mice in Carcinogenicity Studies

Sendai virus (SV), mouse hepatitis virus (MHV), and pneumoniavirus of mice (PVM) are common viral infections of mice. Influenceof these viral infections on the prevalence of liver tumors,lung tumors, and lymphoma is of concern in chemical carcinogenicitystudies. Body weight, survival, and tumor prevalence of B6C3F1mice with and without viral infections in 33 male and 34 femaleuntreated control groups and 32 male and 32 female low- andhigh-dose groups of 2-year chemical carcinogenicity studieswere evaluated. In male mice, the SV infection was associatedwith significantly (p < 0.05) higher survival of control,low-dose, and high-dose groups, and higher prevalence of livertumors and lymphoma. The increases in tumor prevalence are possiblydue to an increase in the survival of male mice that had SVinfection. However, when interlaboratory variability and time-relatedeffects were taken into account, the number of significant effectswas consistent with the expected false-positive rate inherentto the statistical procedures. The MHV and PVM infections didnot cause consistent changes in body weight, survival, and tumorprevalences in the control and chemical treatment groups ofmale mice. Viral infections did not cause consistent increasesor decreases in body weight, survival, or tumor prevalence inthe control and chemical treatment groups of female B6C3F1 mice.     

The Broiler Chicken as a Model for Immunotoxicity Assessment: 1. Standardization of in Vitro Immunological Assays

The Broiler Chicken as a Model for Immunotoxicity Assessment.1. Standardization of in Vitro Immunological Assays. BAECHER-STEPPAN,L., NAKAUE, H. S., MATSUMOTO, M., GAINER, J. H., AND KERKVLIET,N. I. (1989). Fundam. Appl. Toxicol. 12, 773–786. Thebroiler chicken was developed as an alternative animal modelto laboratory rodents for immunotoxico-logic assessment. Invivo treatment with 100–200 mg/kg cyclophosphamide (CY)was used as a known immunosuppressive treatment to standardizethe assay systems. Protocols for assessing specific immunologicalfunctions were developed in specific pathogen-free (SPF) broilersto measure lymphocyte blastogenesis to T-cell (concanavalinA and phytohemagglutinin) and B cell (Staphylococcus aureuscells) mitogens, delayed-type hypersensitivity (Dm) to tuberculin,natural killer (NK) cell cytotoxicity, plaque-forming cell (PFC)response to sheep red blood cells (SRBC), and serum antibodytiters to SRBC. CY was an effective immunosuppressant in thebroiler system for assessment of lymphocyte responsiveness tomitogenic stimulation, DTH reactivity, and the antibody responceto SRBC as assessed by PFC and serum antibody titers. NK cytotoxicitywas not altered on a cellular level following treatment withCY at a dose that preduced greater than 75% depletion of spleencellularity. However, under these conditions, it must bc assumedthat the capacity of CY-treated birds to mediate NK effectorfunctions would be reduced. These results demonstrate the applicabilityof the broiler chicken as an animal model for immunotoxicitytesting.     

Cell-Mediated Immunity in Infertility

ABSTRACT: A role of cell-mediated immunity in immunologic infertility is indicated by a number of animal immunization studies and by reported clinical associations between cellular immune responses and infertility. Furthermore, recent technical advances in the field of cellular immunology have enabled advanced studies on the cellular and soluble mediators of cell-mediated immune responses and their interactions with reproductive processes. In this article we review some of the recent technical and conceptual advances in cellular immunology, the classic literature on cellular immune responses in infertility, and recent evidence that certain products of activated lymphocytes and macrophages significantly affect reproductive functions.