Catecholamine facilitated reentrant ventricular tachycardia: uncoupling of adenosine's antiadrenergic effects.

Introduction: Adenosine has no direct electrophysiologic function in ventricular tissue, but in the presence of cyclic adenosine monophosphate (cAMP), stimulation exerts a potent antiadrenergic effect. This effect has been exploited in the recognition and treatment of ventricular tachycardia (VT) due to cAMP-mediated triggered activity and automaticity, which are respectively terminated and suppressed by adenosine. However, the effects of adenosine on catecholamine-facilitated reentrant VT are unknown.

Topical papaverine and facial nerve dysfunction in cerebellopontine angle surgery.

Hypothesis: Topical application of 3% papaverine hydrochloride in the cerebellopontine angle (CPA) produces reversible conduction block of the facial nerve.

Background: A case of loss of spontaneous and evoked facial muscle activity, and transient postoperative facial paralysis, after topical application of papaverine in the CPA during surgery for an acoustic neuroma using intraoperative cranial nerve monitoring is reported. Other cases of transient neurologic dysfunction after use of this drug have been reported.

Solubility study of albumin solders for laser tissue-welding.

Background/objective: Current albumin solders for tissue-welding are soluble in physiological fluids, prior to laser irradiation. These solders are therefore subjected to mechanical alterations, which can weaken the solder-tissue repair. In this study, an albumin solder (laser activated) was developed with low solubility and with the ability to retain (partially) its mechanical characteristics in saline solution.

Laser tissue welding: a urological surgeon's perspective.

Laser tissue welding has proven its efficacy in the laboratory setting when compared with more traditional modalities of tissue reapproximation. In the clinical environment, several areas including urethral reconstructive surgery have shown great promise. Several technological advancements including solder development, chromophore enhancement and temperature control have improved upon the welding process and have added more precision and reproducibility to the technique.

Radiologic surveillance of acoustic neuromas.

Objective: This study aimed to define the incidence and rate of tumor growth of acoustic neuromas (ANs) in patients who have undergone radiologic surveillance.

Data Sources: MEDLINE literature searches covering the period of January 1966-June 1997 were performed as well as a review of the bibliographies of the studies that were found.

Study Selection: Criteria for inclusion of a study in this metaanalysis were: a defined group of patients diagnosed with an AN for whom radiologic surveillance was the selected strategy of management, limited inclusion of patients with neurofibromatosis type II (NF II) ANs, no recurrent ANs, data that could be extracted and pooled with other studies, and no duplication of patient populations between studies.

Flexible transinguinal laparoscopy to assess the contralateral ring in pediatric inguinal hernias.

The incidence of contralateral patent processus vaginalis (CPPV) is >50% in infants with clinical unilateral inguinal hernia (CUIH) and decreases only slowly with advancing age. Laparoscopy through the hernia sac (transinguinal laparoscopy) to detect suspected CPPV is a safe and efficient way to minimize routine contralateral inguinal exploration, but can be technically difficult. We used flexible urologic instruments and/or angled cystoscopic lenses to make transinguinal laparoscopy easier.

Testicular sperm extraction for nonobstructive azoospermia: results of a multibiopsy approach with optimized tissue dispersion.

Objectives: Testicular sperm extraction (TESE) is an effective procedure to retrieve sperm from some men with nonobstructive azoospermia (NOA). To optimize treatment effectiveness, we have reviewed our experience with TESE for NOA to better understand technical factors needed for sperm retrieval and lead to an optimized approach to TESE.

Methods: Eighty-one men with confirmed NOA underwent attempted TESE using an open technique under optical magnification.

Emergency magnetic resonance of the brain.

We will review the role of magnetic resonance (MR) in assessment of patients with acute neurological abnormalities. The major stumbling block to the use of MR in these patients is the belief that MR is insensitive to hyperacute (<12 h) intracranial hemorrhage and acute subarachnoid hemorrhage (SAH). Hyperacute hemorrhage has characteristic features on MR.

"Triggered trap": nevoid malignant melanoma.

Nevoid malignant melanoma probably represents an early form of nodular malignant melanoma in which there is little proliferation of melanocytes in the epidermis and a dermal proliferation that mimics some features of a compound or intradermal nevus, which is difficult to recognize as being due to malignant melanoma. The lesions can contain either small nevoid cells or larger cells that resemble those in Spitz's nevi. Overall the lesions are symmetrical, have minimal proliferation in the epidermis, and often have dispersion of cells at the base.

Aspirin prevents tumors in a murine model of familial adenomatous polyposis.

Background: Both human and murine studies suggest that anti-inflammatory drugs prevent intestinal neoplasia. The purpose of this study was to investigate the role of aspirin as a chemopreventive agent for colorectal cancer.

Methods: We administered aspirin to the Min/+ mouse, an animal with a germline mutation in Apc, a gene that is essential for normal epithelial cell growth and differentiation.

Nutrition and the immune system of the gut.

Studies suggest that the development and expression of the regional immune system in the gastrointestinal (GI) tract is relatively independent of systemic immunity. This is reflected in significant differences in functional response of T cells and B cells and affects cytokine patterns and activation pathways when regional immunity is compared to systemic immunity. Nutrients have fundamental and regulatory influences on the immune response of the GI tract and, therefore, on host defense.

Mycobacterium tuberculosis infection of a native polycystic kidney following renal transplantation.

Background: Tuberculosis is a recognized complication following renal transplantation. Patients with autosomal dominant polycystic kidney disease are increasingly being offered renal transplantation as an alternative to chronic hemodialysis. These patients are uniquely susceptible to serious upper urinary tract infections that are associated with significant morbidity and mortality.

Use of a free bladder mucosal graft for simple repair of vesicovaginal fistulae.

The aim of this paper is to describe a simple, fast, and effective method for repair of difficult vesicovaginal fistulae by means of a free bladder mucosal graft. Six patients with high, large, multiple, or recurrent vesicovaginal fistulae were treated using a free bladder mucosal graft. Three patients underwent "early" repair (less than 3 months from time of injury) and 3 "late" repair (more than 6 months from time of injury).

Aminopeptidase A expression and enzymatic activity in primary human renal cancers.

The gp160 human kidney differentiation antigen is identical to human aminopeptidase A (APA), a zinc-dependent cell-surface metallopeptidase which hydrolyzes peptides with N-terminal acidic residues. GP160/APA is constitutively expressed by proximal tubule cells, the normal cellular counterpart of most renal cancers (RCs). Immunohistochemical analysis of gp160/APA protein expression in 62 primary renal tumor specimens using monoclonal antibody S4 revealed heterogeneous or homogeneous expression of gp160/APA in 46/51 (90%) of clear cell carcinomas in contrast with 1/8 (13%) papillary renal tumors and 0/3 oncocytomas (p<0.

BRa (HPA-5b) incompatibility may cause thrombocytopenia in neonates of mothers with immune thrombocytopenic purpura.

Purpose: The association of anti-Br(a) immunoglobulin G (IgG) platelet alloantibodies with the development of thrombocytopenia in neonates of mothers with autoimmune thrombocytopenic purpura (ITP) is reported.

Methods: Between March 1994 and July 1997, 28 consecutive pregnant women with ITP seen at New York Hospital were screened for platelet-reactive antiglycoprotein (glycoprotein [GP] IIb/IIIa, Ib/IX, and Ia/IIa) antibodies.

Results: The sera from 6 of these 28 women contained IgG alloantibodies to GP Ia/IIa directed against the Br(a) (HPA-5b) antigen.

Common peroneal neuropathy secondary to squatting during childbirth.

Background: Common peroneal neuropathy occurs fairly frequently in the adult population; however, very few cases of peroneal neuropathy after prolonged squatting have been reported.

Case: A 29-year-old woman noted right foot numbness and weakness immediately after childbirth, which involved 15-30 minutes of pushing in a squatting position. Physical examination and an electrodiagnostic study confirmed a common peroneal neuropathy.

Laser tissue welding.

Laser tissue welding is a technologic innovation that is beginning to move from the theoretical laboratory environment to the reality of clinical application. This article reviews the concepts, potential advantages, and techniques involved in laser tissue welding as they apply to urology.

Surgical treatment of acquired external auditory canal atresia.

Objective: This study aimed to analyze the etiologies, clinical presentation, treatment options, and results of treatment in a series of patients with acquired external auditory canal atresia (AEACA) and to put this analysis in the context of the existing literature on this topic.

Study Design: The study design was a retrospective case review.

Setting: The study was performed at a tertiary otologic referral practice.

The neuropeptide/mast cell secretagogue substance P is expressed in cutaneous melanocytic lesions.

Substance P (SP) is a neuropeptide found in both the central and peripheral nervous system. In the skin, SP-containing neurons stimulate the release of histamine from connective tissue mast cells (MC). SP also can potentiate neoangiogenesis and induce dermal fibrosis.

The sulfide metabolite of sulindac prevents tumors and restores enterocyte apoptosis in a murine model of familial adenomatous polyposis.

Sulindac, a non-steroidal anti-inflammatory drug (NSAID), is effective in treating intestinal adenomas in humans with Familial Adenomatous Polyposis (FAP) and in preventing intestinal tumors in the C57Bl/6J-Min+ (Min) mouse, an animal model of FAP. Sulindac is a prodrug metabolized by the liver and intestinal flora to a sulfone, which has no anti-inflammatory activity, and a sulfide, which is the active anti-inflammatory metabolite. In this study, we determined which of these metabolites is responsible for the anti-tumor effect of sulindac in Min mice.

Cardiac operations in patients with cirrhosis.

Background: A retrospective review was performed to determine the outcome after cardiac operations in patients with a documented history of noncardiac cirrhosis.

Methods: The charts of patients admitted to the cardiothoracic surgical service between 1990 and 1996 were reviewed, and 13 patients with a preoperative history of cirrhosis were identified. The severity of preoperative liver disease was graded according to the criteria of Child.