Cocaine-induced suppression of renin secretion is mediated in the brain: investigation of cardiovascular and local anesthetic mechanisms.

Acute cocaine reduces renin secretion. To determine a peripheral versus central site of action, intracerebroventricular (ICV) versus intraperitoneal (IP) injections of cocaine were compared. Cocaine was more potent reducing plasma renin activity (PRA) and concentration (PRC) when injected ICV (0.050 mg/kg) than IP (5 mg/kg), suggesting a central site of action. Furthermore, addition of cocaine (10(-4) M) to kidney slices in vitro did not influence renin release, indicating that cocaine does not suppress renin secretion by acting directly in the kidney. We also investigated whether the hypertensive or local anesthetic properties of cocaine mediate its inhibition of renin secretion. Therefore, we compared the cardiovascular and endocrine effects of cocaine with those of the local anesthetic drug procaine. Both cocaine and procaine (500 micrograms/kg, ICV) produced rapid and short-term increases in blood pressure, but cocaine decreased PRC whereas procaine increased PRC. Intra-arterial (IA) and IP injections of cocaine also reduced PRC whereas procaine had no effect (IA) or elevated PRC (IP). Together, the data suggest that cocaine decreases renin secretion by acting in the brain. It is not likely that the cardiovascular or local anesthetic actions of cocaine are the main cause of its suppressive effect on renin secretion.     

Perianal ulcers of tubercular origin. A report of 3 new cases]

The rate of patients with extrapulmonary tuberculosis has increased in the last years (about 5% of all cases), and displaying a wide spectrum of clinical manifestations. Among them, the anal localization is a rare occurrence (0.7%) according to available published data. During the last two years, we have diagnosed and treated three patients with perianal tuberculous lesions manifested by ulcers. All three were males, associated with active pulmonary tuberculosis, and one with intestinal involvement which required surgical treatment. Based on this experience, we have reviewed the different etiopathogenic, clinical, diagnostic and therapeutic manifestations of this picture, emphasizing the importance of suspicion, and its diagnostic easiness if the different infectious and inflammatory diseases at this level are taken into account.     

The Bj?rk-Shiley valve prosthesis. Analysis of long-term evolution.

The long-term follow-up of 831 patients who underwent valve replacement with Bj?rk-Shiley Delrin and standard Pyrolyte prostheses (341 aortic, 345 mitral, and 145 mitroaortic) between 1971 and 1980 is reviewed. The follow-up concluded in 1985. Cumulative follow-up amounted to 4724 years, with a mean of 5.68 years per patient. Data on survival were obtained in 754 patients (complete follow-up in 90.8% of cases). Perivalvular leak was the most frequent complication in aortic valve replacement, whether isolated or combined, with values significantly higher than those registered in isolated mitral replacement (p < 0.001 in both cases). No correlation was found between this complication and valve calcification, but it was statistically correlated with the size 19 model (p < 0.05). Prosthetic stenosis was more common in mitral than in aortic replacement (p < 0.001), and of the former, size 23 was that most often affected (p < 0.001). The earliest case of mitral pannus was diagnosed 20 months postsurgery, and from 45 months on this pathology was the cause of every case of stenosis. The risk of thromboembolism was similar in aortic, mitral, and double prostheses, while it was the single most frequent complication in isolated mitral replacement. Prosthetic thrombosis was triggered in all cases in which it occurred by discontinuance of anticoagulant therapy. Anticoagulant-induced hemorrhages were more frequent in double replacement than in mitral (p < 0.05) and aortic valve replacement. Endocarditis was the complication that produced the highest mortality rate in all groups; the frequency of this infection was higher among patients with double prostheses when compared with either aortic replacement (p < 0.05) or mitral replacement (p < 0.001). The risk of suffering endocarditis was correlated with the existence of active preoperative infection in patients with mitral prostheses and double prostheses (p < 0.001 in both cases). Overall morbidity was higher in the double replacement group with respect to the mitral group (p < 0.01). The rate of mortality was also higher among the double valve replacement patients when compared with both the aortic (p = 0.0002) and mitral (p = 0.006) groups.     

Lack of association between endothelial nitric oxide synthase (NOS3) gene polymorphisms and suicide attempts

Objective  

The aim of this study is to investigate the association between two polymorphisms of endothelial nitric oxide synthase (NOS3) and suicide attempts.     

Role of the intraocular irrigating solutions in the pathogenesis of the postvitrectomy retinal edema

Alterations in the vitreo-retinal barrier can modify the exchange of water taking place between the retina and the vitreous body and cause retinal edema to develop. To verify this fact, albino rabbits were subjected to vitrectomies perfusing various intraocular irrigating solutions for various durations. The following conclusions were drawn from these experiments: Ringer's Lactate and physiological saline solutions are more edematogenous than BSS plus; the induced edema is more severe, the longer the perfusion. We have also confirmed that this edema is inhibited by topically administered indomethacin, which proves that in the rupture of blood-retinal barriers during the vitrectomy, prostaglandins play an important role.     

Do Spanish patients drink alcohol while undergoing treatment with benzodiazepines?

In this study, we analyzed patterns of combined benzodiazepines and alcohol use among the Spanish general population over the age of 16 years. The study was based on information from the 1997 Spanish National Household Health Survey. A total of 6,396 persons over 16 years of age, a representative sample of noninstitutionalized Spaniards, were surveyed. One percent of the population are consumers of benzodiazepines and daily drinkers of alcohol; fundamentally, these consumers are men, of whom 15.4% drink alcohol at a high level (>50 units/week). Findings show the frequency of concurrent use of benzodiazepines and alcohol by the Spanish population.     

Genetic changes at the beta-2-adrenergic receptor locus on chromosome 5 in human colorectal carcinomas.

Matched normal/tumor DNA pairs from 44 colorectal carcinoma patients were examined for tumor-specific genetic changes using a probe for the beta-2-adrenergic receptor (ADRB2R) gene on chromosome 5. This locus (5q31-q32) maps close to the site of chromosomal deletions recently reported to occur in colorectal carcinomas and distal to the chromosomal location of the familial adenomatous polyposis (FAP) gene (5q21-q22). Our investigation shows tumor-specific allele loss or allelic rearrangement of at least 29% at the AdRb2R locus on chromosome 5 in informative cases. These results suggest that the mechanism by which colorectal carcinomas lose genetic material on chromosome 5 can affect this functional gene located distally to the FAP gene. The possible functional significance that ADRB2R gene changes may have in neoplastic progression is discussed.