Use of the Syrian Hamster Embryo Cell Transformation Assay for Determining the Carcinogenic Potential of Heavy Metal Compounds

Cobalt sulfate hydrate, gallium arsenide, molybdenum trioxide,vanadium pentoxide, and nickel sulfate heptahydrate were testedin the Syrian hamster embryo (SHE) assay in order to increasethe SHE assay database for heavy metals. All five compoundsproduced significant morphological transformation at one ormore doses in a dose-responsive manner. Cobalt sulfate hydrate,gallium arsenide, molybdenum trioxide, and nickel (II) sulfateheptahydrate were all positive with a 24-hr exposure, suggestingdirect DNA perturbation. Vanadium pentoxide was negative witha 24-hr exposure, but positive with a 7-day exposure. This patternof response (24-hr SHE negative/7-day SHE positive) has beenseen with other chemicals which have tumor promotion-like characteristics.Since the inception of the use of the SHE cell transformationassay for detecting the neoplastic transformation potentialof chemicals, over 42 heavy metal compounds have been testedin this assay. Based on the 24 metal compounds which have beentested in the SHE, Salmonella, and some type of rodent bioassay,the SHE assay is 92% concordant with rodent bioassay carcinogenicityresults, including a sensitivity of 95% (21/22) and a specificityof 50% (1/2). At this time, the measure of SHE assay specificityfor rodent carcinogenicity of metals is limited by the paucityof metal compounds which are rodent noncarcinogens. The Salmonellaassay results are only 33% concordant with the rodent bioassayfor these same chemicals. This relatively high concordance betweenthe SHE assay and the rodent bioassay carcinogenicity resultsdemonstrates the utility of the SHE assay for determining thecarcinogenic potential of heavy metal compounds in rodent Cancerbioassays.     

Clinical Experience With the Prevention of Rh-lsoimmunization: A Historical Comparative Analysis

ABSTRACT: Clinical experience with prevention of Rh-immunization is reviewed. The pathogenesis of hemolytic disease and the chemistry of prophylaxis is explained. The factors which effect antigenic expression are delineated. The clinical indications for prevention of AMIS are reviewed. International data pertaining to Rhesonativ are presented from postpartum trials and antepartum trials. A protocol for antepartum administration of anti-Rh immunoglobulin is given.     

The atrophogenic effect of crude coal tar on human epidermis

The effects of crude coal tar on human epidermis were studied in fourteen healthy young adult males. A 20%, reduction in viable epidermal thickness, as determined by computer assisted analytical microscopy, was observed after 40 days of topical treatment. Prior to this long term effect of crude coal tar, an initial transient hyperplasia was observed during the first 2 weeks of treatment. These findings indicate that crude coal tar by itself can act as a cytostatic agent on normal human skin, when applied intensively.     

Peritonitis in Patients with Liver Disease and Ascites

Peritonitis in patients with pre-existing liver disease and ascites may be secondary to a local abdominal condition which potentially requires surgery for cure, or alternatively, may be spontaneous in origin. For the latter, antimicrobials are therapeutic while surgery is contraindicated. An easily accessible and important clue for distinguishing these forms of peritonitis may be found in the microbiology of ascitic fluid. Visualization on gram stain smear or recovery on culture of multiple organisms and/or anaerobes favors local abdominal disease over spontaneous peritonitis. The presence of Candida species in the ascitic fluid of such patients, although less common, is highly significant. In the absence of peritoneal dialysis, recent abdominal surgery, or risk factors for disseminated candidiasis, the isolation of Candida suggests specifically gastrointestinal perforation.     

Transseptal Left Ventricular Lead Placement Using Snare Technique

Background: Coronary sinus (CS) lead placement for cardiac resynchronization therapy has a failure rate of ～5–10%. Here we describe a way of implanting an endocardial left ventricular (LV) lead via a transseptal puncture (TSP), using a GooseNeck snare and active fixation lead. Methods: Three male patients (67–83 years) with failed or extracted epicardial LV leads implanted via the CS had an endocardial LV lead implanted. TSP was performed via a femoral vein. The active fixation pacing lead was advanced to the right atrium from a subclavian vein. A GooseNeck snare was passed via the TSP sheath and used to grasp the tip of the pacing lead. The sheath, GooseNeck snare, and pacing lead tip were then passed to the left atrium by sliding the system up the TSP guidewire and across the interatrial septum before deflecting the lead to permit implantation in the left ventricle. Results: Successful implantation was performed in all patients with an LV implant time of 25–55 minutes. Conclusion: The use of a GooseNeck snare via a deflectable transseptal sheath represents a reliable alternative method for endocardial LV lead placement in patients with failed CS LV lead implantation. (PACE 2012; 35:1248–1252)     

MICROSURGICAL REPAIR OF THE ADOLESCENT VARICOCELE

Purpose

Since clinically apparent varicoceles may affect testicular volume and sperm production, early repair has been advocated. However, repair of the pediatric varicocele with conventional nonmagnified techniques may result in persistence of the varicocele after up to 16% of these procedures. Also testicular artery injury and postoperative hydrocele formation can occur after nonmagnified repair. The microsurgical technique has been successfully completed in a large series of adults with a dramatic reduction in complication and recurrence rates. We report our experience with the microsurgical technique in boys.

Materials and Methods

A total of 30 boys (average age 15.9 years) underwent 42 microsurgical varicocelectomies (12 bilateral). All patients had a large left varicocele. Indications for repair included testicular atrophy (size difference between testicles of greater than 2 ml.) in 20 boys, pain in 5 and a large varicocele without pain or testicular atrophy in 5. Six boys were referred following failure of conventional nonmicrosurgical techniques. All boys were examined no sooner than 1 month postoperatively (mean followup 12).

Results

Preoperative volume of the affected testis averaged 13.0 ml., and an average size discrepancy between testicles of 2.8 ml. was noted before unilateral varicocelectomy. No cases of persistent or recurrent varicoceles were detected, and 1 postoperative hydrocele resolved spontaneously. After unilateral varicocelectomy the treated testes grew an average of 50.1%, while the contralateral testes grew only 23%. Overall, 89% of patients with testicular atrophy demonstrated reversal of testicular growth retardation after unilateral varicocelectomy. In contrast, both testes showed similar growth rates after bilateral varicocelectomy (45% left testis, 39% right testis).

Conclusions

The meticulous dissection necessary to preserve arterial and lymphatic supply, and to ligate all spermatic veins in the pediatric patient is readily accomplished using a microsurgical approach, and results in low recurrence and complication rates. Rapid catch-up growth of the affected testis after microsurgical varicocelectomy suggests that intervention during adolescence is effective and warranted.