Vasoconstrictor and cardiotonic actions of Haloxylon recurvum extract

Intravenous administration of an ethanolic extract of Haloxylon recurvum (30–300 μg/kg) caused a rise in arterial blood pressure in normotensive anaesthetized rats. Pretreatment of animals with phentolamine (1 mg/kg) abolished the vasoconstrictor response of the plant extract in a way similar to that of norepinephrine (NE). In an isolated rabbit aorta preparation, both plant extract and NE produced contractile responses which were blocked by phentolamine (0.3 μg/mL). In isolated guinea-pig atria, the plant extract caused positive inotropic and chronotropic responses similar to that of NE and was blocked by propranolol (0.3 μg/mL). These results suggest that vasoconstrictor and cardiac stimulatory effects of the plant extract are mediated through mechanisms similar to those of NE (stimulation of α-adrenergic receptors in the blood vessels and cardiac β-receptors respectively) and hence this plant contains sympathomimetic constituent(s).     

Resection of benign esophageal stricture through a minimally invasive endoscopic and transgastric approach

Recurrent benign esophageal strictures that are refractory to dilation can be difficult to manage. We report a novel technique for treatment of a recurrent esophageal stricture using a minimally invasive endoscopic and transgastric approach. The patient is a 40-year-old women who developed a recurrent distal esophageal stricture after repair of an esophageal perforation. Multiple prior dilations had been unsuccessful in achieving sustained esophageal patency, and the patient presented with a complete distal obstruction demonstrated on barium esophagram. Two flexible endoscopes were used: one placed through the mouth and another through a gastrostomy. While the transilluminated lesion was visualized from below the obstruction was traversed with an endoscopic aspiration needle from above. A guidewire was placed through the needle and pulled out the gastrostomy. Both the esophageal lesion and the gastrostomy tract were then serially dilated over the wire. After dilation the residual stricture was resected using a circular stapler placed through the dilated gastrostomy tract. After this procedure the patient maintained esophageal patency with a diminished need for dilation. Details of our technique are described and the literature is reviewed.     

Chemoprevention of prostate carcinogenesis by DFMO and/or finasteride treatment in male Wistar rats

In the present study the chemopreventive activities of DFMO, the irreversible inhibitor of ornithine decarboxylase, and finasteride, the inhibitor of prostatic 5a-reductase, against the development of chemically induced prostate adenocarcinoma by methylnitrosourea/testosterone propionate in male Wistar rats were investigated. According to histological examination, oral administration of DFMO and finasteride, either alone or combined, for two months to MNU/TP-inoculated rats reduced the tumor incidence to 11.11%, 10% and 10%, respectively, compared to tumored controls (64.3%). DFMO and/or finasteride treatment resulted in significant reductions in the wet weight of the prostate gland and seminal vesicles and its ratio relative to the total body weight, as well as the levels of prostate total protein, DNA, RNA and DNA/RNA ratio, compared to tumored controls. However, the effect of the combined treatment was of no statistical significance compared to single DFMO or finasteride treatment, as demonstrated by the non-significant differences between the mean values of most of the studied parameters. The tumor chemopreventive activity and the prostate growth inhibitory effect of DFMO and finasteride were due to suppression of prostate polyamine synthesis. ANOVA test revealed that the relative weight of the prostate as well as blood and tissue polyamine levels could be used as significant endpoint biomarkers for DFMO and finasteride as cancer chemopreventive agents.     

Uncommon high-risk lesions of the breast diagnosed at stereotactic core-needle biopsy: clinical importance

PURPOSE: To assess the outcome of papillary lesions, radial scars, or lobular carcinoma in situ (LCIS) diagnosed at stereotactic core-needle biopsy (SCNB). MATERIALS AND METHODS: Retrospective review of 1,236 lesions sampled with SCNB yielded 22 papillary lesions, nine radial scars, and five LCIS lesions. Diffuse lesions such as papillomatosis, papillary ductal hyperplasia, papillary ductal carcinoma in situ (DCIS), and atypical lobular hyperplasia were not included. The mammographic findings, associated histologic features, and outcome were assessed for each case. RESULTS: Sixteen papillary lesions were diagnosed as benign at SCNB. Of these, five were benign at excision, and 10 were unremarkable at mammographic follow-up. At excision of an unusual lesion containing a microscopic papillary lesion, DCIS was found. Three of four papillary lesions suspicious at SCNB proved to be papillary carcinomas; the fourth had no residual carcinoma at excision. Eight of nine radial scars were excised, which revealed atypical hyperplasia in four scars but no malignancies. One LCIS lesion was found at excision to contain DCIS. CONCLUSION: Benign or malignant papillary lesions were accurately diagnosed with SCNB in the majority of cases. Cases diagnosed as suspicious for malignancy or with atypia or unusual associated histologic findings should be excised. No malignancies were found at excision of radial scars diagnosed at SCNB. Surgical removal of these lesions following SCNB may not be routinely necessary. DCIS was found in one lesion diagnosed as LCIS at SCNB, which suggests that removal of these lesions may be prudent.     

Exercise hemodynamics of aortic prostheses: comparison between stentless bioprostheses and mechanical valves

BACKGROUND: Nonstented bioprostheses have been associated with lower resting gradients than stented bioprostheses or mechanical valves. We compared the hemodynamic performance of nonstented bioprostheses and mechanical valves with normal native aortic valves at rest and exercise. METHODS: Dobutamine echocardiography was used to assess gradients and effective orifice area index at rest and exercise in patients with the Toronto stentless porcine valve (TSPV; n = 13; mean implant size 25.7 mm), Medtronic Freestyle (FR; n = 11; mean implant size 23.9 mm), Sorin Bicarbon (SOR; n = 11; mean implant size 24.5 mm), St. Jude Medical (SJM; n = 10; mean implant size 21.3 mm), and normal native aortic valves (NOR; n = 10). RESULTS: All groups demonstrated a major rise in cardiac output at maximal dobutamine infusion. At rest and exercise, respectively, mean gradients were 5.48 +/- 1.1 mm Hg and 5.83 +/- 0.9 mm Hg for TSPV, 5.68 +/- 1.2 mm Hg and 7.50 +/- 1.7 mm Hg for FR, 10.29 +/- 1.4 mm Hg and 20.78 +/- 2.7 mm Hg for SJM, 5.26 +/- 0.8 mm Hg and 11.1 +/- 1.8 mm Hg for SOR, and 1.54 +/- 0.4 mm Hg and 2.18 +/- 0.7 mm Hg for NOR. In comparison with normal valves, both stentless groups showed no change in mean gradient at exercise, whereas both mechanical groups showed an increase in gradient at exercise (p < 0.04). CONCLUSIONS: Stentless valves behave similarly to normal aortic valves in that there is almost no increase in gradient at exercise. Both mechanical valve groups showed increased gradients at exercise, suggesting that these valves obstruct blood flow. Our data add further evidence that stentless valves are hemodynamically superior to mechanical valves in the aortic position.     

Wound Complications and Treatment of the Infected Implantable Cardioverter Defibrillator Generator

A bstract Since 1980, the automatic implantable cardioverter defibrillator (ICD) has evolved as effective therapy for prevention of sudden cardiac death following documented sustained ventricular tachycardia or fibrillation. During a 5-year period, 412 ICD devices were implanted at the University of Michigan Hospitals with a wound complication rate of 4.1%. In this group, there were 13 infections, 3 erosions of the generator pocket, and 1 wound hematoma. Of the 16 patients with infection or erosion, 12 patients were treated with a rectus abdominis muscle flap closure and 4 with ICD generator removal. In 83% (n = 12) of the muscle flap patients, the wound healed uneventfully. Preoperative chest CT scanning was found to be helpful in identifying probable infection of the epicardial leads. In these cases, all hardware had to be removed to achieve resolution of the infection. We concluded that rectus abdominis muscle flaps were helpful in salvaging infected or exposed ICD generators in the absence of infected epicardial leads.     

A proposed Saudi approach to the ethical utilization of living unrelated kidney donation

We outline a proposal for the use of living unrelated kidney donors for transplantation. This proposal, although recommended by the Saudi National Committee on Renal Transplantation, is still under discussion and has not been implemented yet. We feel that this proposal is ethical with airtight safeguards against commercialization and for the protection of the well-being of the donor with assurance that he or she has not been coerced into donation.