Angiotensin I-converting enzyme modulates neutral endopeptidase activity in the rat.

Angiotensin I is a substrate for both ACE and for neutral endopeptidase 24.11 (NEP). We hypothesized that high ACE expression is related to low NEP activity. Accordingly, circulating and tissue NEP and ACE activities were measured by fluorometry in homozygous rats (F(0) and F(2)) for the Lewis microsatellite allele (LL, low ACE) and for the Brown Norway microsatellite allele (BB, high ACE). Plasma, lung, and aortic ACE activities in F(0) and F(2) were higher in BB rats than in LL rats (P<0.01), whereas left ventricular ACE activity was similar in both genotypes. In contrast, NEP activity in the LL group was higher in the serum, aorta, and lungs in F(0) and F(2) homozygous (P<0.05). Plasma ACE activity was inversely correlated with serum (r=-0.6 and -0.598 in F(0) and F(2), respectively; P<0.03) and lung NEP activities (r=-0.77 in F(0) and r=-0.59 in F(2), P<0.01). Aortic ACE and NEP activities were also correlated (r=-0.696 and -0.584 in F(0) and F(2), respectively; P<0.03). In conclusion, genetically determined high ACE expression in rats is inversely related to tissue NEP activity, which could determine lower angiotensin-(1-7) tissue levels.

A rapid and strong apoptotic process is triggered by hyperosmotic stress in cultured rat cardiac myocytes.

In all cell types, the maintenance of normal cell volume is an essential homeostatic function. Relatively little is known about the induction of apoptosis by hyperosmotic stress and its molecular mechanism in terminally differentiated cardiac myocytes. We compared the apoptotic response of cultured neonatal rat cardiomyoctes to hyperosmotic stress by sorbitol (SOR) with those induced by doxorubicin (Doxo) or angiotensin II (Ang II). We also examined the apoptotic-signaling pathway stimulated by the hyperosmotic stress. Apoptosis was assessed by the observation of: (1) cell viability, (2) DNA fragmentation detected by the TUNEL method and by agarose gel electrophoresis, and (3) poly(ADP-ribose)polymerase (PARP) degradation, and Bcl-XS and Bcl-XL levels by Western blot analysis. Exposure of cardiomyocytes to 0.3 M SOR for 24 h resulted in decreased cell viability and increased generation of oligosomal DNA fragments (2.5-fold of controls). At this time, 83 +/- 5% of SOR-treated myocytes were TUNEL-positive (vs 23.7 +/- 6.8% in controls; P<0.01). PARP levels also decreased by approximately 42% when cardiac myocytes were exposed to SOR. Hyperosmotic stress induced a more rapid and stronger apoptotic response in cardiomyocytes than Doxo or Ang II. In addition, SOR increased 3.2-fold Bcl-XS proapoptotic protein without changes in Bcl-XL antiapoptotic protein levels and in the p53-transactivating activity. Taken together, these results strongly suggest that hyperosmotic stress triggers cardiac myocyte apoptosis in a p53-independent manner, being earlier and stronger than apoptosis induced by Doxo and Ang II.

Non-traumatic intracerebral hemorrhage in young adults living in Guayaquil, Ecuador (South America): analysis of 151 patients.

We studied 151 patients aged 15 to 44 years with non-traumatic intracerebral hemorrhage admitted to a large public hospital over a 10-year period. Patients were evaluated for an association of death or severe disability after the stroke with the following variables: sex, age, location of the hemorrhage, and possible etiology. Lobar hemorrhages were found in 63 (41.7%) patients, putaminal hemorrhages in 39 (25.8%), posterior fossa hemorrhages in 24 (15.9%), and hemorrhages in other locations in 25 (16.6%). A possible etiology was determined in 109 (72.2%) patients. Hypertensive arteriolopathy accounted for 60 (39.7%) cases, rupture of a saccular aneurysm or a vascular malformation for 33 (21.9%), and other etiologies for 16 (10.6%). Thirty-four (22.5%) patients died after the acute event. The age of the patient, the location, and the etiology of the hemorrhage had no prognostic significance for mortality. In contrast, these factors predicted the degree of functional recovery in survivors. The best prognosis was noted in patients younger than 35 years with lobar hemorrhages of undetermined etiology, and the worst prognosis was noted in patients aged 35-44 years with putaminal or posterior fossa hemorrhages related to hypertensive arteriolopathy.

Single-day praziquantel versus 1-week albendazole for neurocysticercosis.

The efficacy of albendazole (15 mg/kg/d for 1 week) was compared with praziquantel (100 mg/kg in three divided doses at 2-hour intervals) for therapy of parenchymal brain cysticercosis. Ten patients were treated with albendazole and 10 patients with praziquantel. Although the total number of cysts was significantly reduced from 64 to 7 in patients treated with albendazole and from 59 to 24 in those treated with praziquantel, the number of patients improving with albendazole was not significantly different from those treated with praziquantel.

[Bilateral medial bulbar infarct related to dolichoectasia of the vertebral artery]. / Infarto bulbar medial bilateral relacionado con dolicoectasia de la arteria vertebral.

INTRODUCTION AND CLINICAL CASE: A 58-year-old hypertensive man presented with the sudden onset of quadriplegia and inability to protrude the tongue. Magnetic resonance imaging showed a bilateral medial medullary infarction associated with an abnormally dilated and partially occluded vertebral artery. CONCLUSION: This is the first clinicoradiological report of a bilateral medial medullary infarction related to vertebral artery dolichoectasia.

[Angiographic findings among Ecuadorian metis population with occlusive cerebrovascular disease of the anterior circulation]. / Hallazgos angiográficos en mestizos ecuatorianos con enfermedad cerebrovascular oclusiva de la circulación anterior.

INTRODUCTION AND OBJECTIVE: This study was conducted to determine the location of arterial lesions in a population of Ecuadorian Mestizos with cerebral infarcts in the carotid territory caused by large-artery atherosclerosis. MATERIAL AND METHODS: Such patients were prospectively entered into a protocol of investigation that included cerebral angiography as the gold standard for evaluation of the extra and intracranial vascular bed. RESULTS: Twelve (60%) of the 20 patients included in this study had symptomatic intracranial lesions, and the remaining 8 (40%) had extracranial lesions. Intracranial lesions were most often located in the middle cerebral artery stem. With the exception that systemic markers of arteriosclerosis were present in 3 of 8 patients with extracranial disease and in none of 12 patients with intracranial disease, we found no differences in stroke risk factors among patients with intra or extracranial lesions. CONCLUSIONS: This study provides suggestive evidence that the distribution of arterial lesions in Ecuadorian mestizos with occlusive cerebrovascular disease is different from that in whites, but similar to that in blacks and orientals.