Office-based surgery and anesthesia: Where are we now?

At the time of publication of this journal, the Center for Urinary Control in Memphis, Tennessee, has performed eight office-based surgical procedures using anesthesia. Patients were aged between 56 and 80 years, and all were ASA I–III class. The procedures involved either cystoscopy with collagen injection into the bladder neck or cystoscopy with indigo laser treatment of the prostate. All patients were prepared by the anesthesiologist prior to the day of surgery, and appropriate laboratory tests were ordered and evaluated. All patients did very well, the surgical field was quiet, and each procedure went very smoothly. Each patient tolerated anesthesia without any adverse effect, was recovered in an adjacent examination room, and was extremely satisfied upon discharge from the office. Anesthesia was induced with Propofol (Diprivan) and sublimaze, maintained with a Propofol infusion and oxygen. The surgeon performed a periprostatic block on the patient having the Indigo laser treatment.     

Respiratory syncytial virus infection and meningococcal disease.

Although viral respiratory tract infections may predispose to meningococcal disease, strong evidence that they do so exists only for influenza. Data on laboratory reported cases of respiratory syncytial virus (RSV) infections and meningococcal disease in England and Wales from mid-1989 to mid-1994 were analysed. Although the rise in RSV cases preceded the rise in meningococcal disease cases each winter, the interval between the rise and fall of the two diseases was inconsistent, no association was found between time series after removal of the seasonal component, and there was no evidence that more cases of meningococcal disease occurred in winters with more RSV disease. RSV may have less effect on the two most likely mechanisms whereby influenza predisposes to meningococcal disease, namely lowered immunity and impaired pharyngeal defences.     

Relative effect of surgery and radiotherapy on the internal jugular vein following functional neck dissection

We examined the internal jugular veins in three groups of patients who had undergone (1) a functional neck dissection and radiotherapy, (2) a functional neck dissection alone, or (3) radiotherapy alone, using a noninvasive color Doppler ultrasound scan. The internal jugular veins were ultrasonically bilaterally normal in 18% of patients who had undergone a functional neck dissection and radiotherapy, in 88% of patients who had undergone a functional neck dissection alone, and in 57% of patients who had undergone radiotherapy alone. The combination of a functional neck dissection and radiotherapy significantly affected the internal jugular vein when compared with a functional neck dissection alone.     

Laminin-5-enriched extracellular matrix accelerates angiogenesis and neovascularization in association with ePTFE

The performance of biomedical implant devices is often limited by inappropriate tissue responses associated with synthetic materials used in device construction. Adverse healing responses, in particular the lack of an extensive vascular supply in the peri-implant tissue, are believed to lead to the ultimate failure of many of these medical devices. Accelerated formation of new blood vessels in the peri-implant tissue and within porous polymeric implants is hypothesized to improve the performance of such biomedical implant devices. The current study evaluated the use of cell-mediated, extracellular matrix modification of expanded polytetrafluoroethylene (ePTFE) to increase vessel growth in peri-implant tissue and within the pores of the implants. Discs of ePTFE were modified through cell-mediated matrix deposition using epithelial and endothelial cell lines with variable deposition of collagen types, fibronectin, and laminin types. Cell matrix-modified discs, Matrigel-coated discs, and nonmodified discs were implanted in both the adipose and subcutaneous tissues of the rat. Following a 5-week implant period, samples were removed and evaluated histologically and morphometrically for the presence of blood vessels in the peri-implant tissue and within the pores of the polymer as well as for the presence of activated macrophages and monocytes. A significantly increased presence of activated macrophages and monocytes was associated only with the samples modified with the matrix from a human microvessel endothelial cell line. Increased vessel density was identified in association with those ePTFE samples modified with either the 804-G, HaCaT, or II-4 cell matrices, all of which have extracellular matrices enriched in the protein laminin-5.     

An efficient method for cloning human autoantigen-specific T cells

T-cell clones are valuable tools for investigating T-cell specificity in infectious, autoimmune and malignant diseases. T cells specific for clinically-relevant autoantigens are difficult to clone using traditional methods. Here we describe an efficient method for cloning human autoantigen-specific CD4+ T cells pre-labelled with CFSE. Proliferating, antigen-responsive CD4+ cells were identified flow cytometrically by their reduction in CFSE staining and single cells were sorted into separate wells. The conditions (cytokines, mitogens and tissue culture plates) for raising T-cell clones were optimised. Media supplemented with IL-2+IL-4 supported growth of the largest number of antigen-specific clones. Three mitogens, PHA, anti-CD3 and anti-CD3+anti-CD28, each stimulated the growth of similar numbers of antigen-specific clones. Cloning efficiency was similar in flat- and round-bottom plates. Based on these findings, IL-2+IL-4, anti-CD3 and round-bottom plates were used to clone FACS-sorted autoantigen-specific CFSE-labelled CD4+ T cells. Sixty proinsulin- and 47 glutamic acid decarboxylase-specific clones were obtained from six and two donors, respectively. In conclusion, the CFSE-based method is ideal for cloning rare, autoantigen-specific, human CD4+ T cells.     

Antigen-induced tolerance by intrathymic modulation of self-recognizing inhibitory receptors

CD1d-restricted invariant natural killer T cell (iNKT cells) have a limited T cell receptor (TCR) repertoire and share characteristics common to T cells and natural killer cells. While intrathymic selection facilitates the production of T cells carrying self major histocompatibility complex-restricted TCRs, natural killer cells carry an appropriate repertoire of self major histocompatibility complex-recognizing receptors to avoid self-reactivity. Here we show that chronic exposure to specific glycolipid antigen resulted in iNKT cell disappearance and thymus-dependent repopulation of iNKT cells with increased expression of inhibitory Ly-49 molecules that resulted in impaired responsiveness. Thymic selection of peripheral Ly-49-expressing iNKT cell repertoire inhibited cytokine production and other functions in vivo. These observations emphasize the acquisition of self-recognizing inhibitory receptors on NKT cells as a previously unknown mechanism of thymic tolerance after chronic antigen exposure.