Biomedical subjects

R Cabello

Publications and source records attributed to R Cabello.

6 recordsLinked to original sources

PubMed2004

Calorie restriction attenuates age-related alterations in the plasma membrane antioxidant system in rat liver.

Aging is associated with increased production of reactive oxygen species and oxidation-induced damage to intracellular structures and membranes. Caloric restriction (CR) is the only non-genetic method proven to extend lifespan in mammals. Although the mechanisms of CR remain to be clearly elucidated, reductions in oxidative stress have been shown to increase lifespan in several model systems. Oxidative stress can be attenuated by CR. Mitochondria and plasma membrane (PM) are normal sources of free radicals. The PM has a trans-membrane redox system that provides electrons to recycle lipophilic antioxidants, such as alpha-tocopherol and coenzyme Q (CoQ). The idea developed in this study is that the PM is intimately involved in cellular physiology controlling the relationship of the cell to its environment. PM is the key for protecting cellular integrity during aging. Specifically, we have investigated age-related alterations and the effects of CR in the trans-PM redox (antioxidant) system in rat liver. We found that age-related declines in the ratio of CoQ(10)/CoQ(9) and alpha-tocopherol in liver PM were attenuated by CR compared to those fed ad libitum (AL). CoQ-dependent NAD(P)H dehydrogenases were increased in CR old rat liver PMs. As a consequence, the liver PM of CR old rats was more resistant to oxidative stress-induced lipid peroxidation than AL rats. Thus, our results suggest that CR induces a higher capacity to oxidize NAD(P)H in the PM of old rat livers and as a result, a higher resistance to oxidative stress-induced damage.

Aging↗

PubMed1994

The Mexican experience with laparoscopic cholecystectomy and common bile duct exploration. A multicentric trial.

We present here the initial data collected since the first laparoscopic cholecystectomy (LC) was performed in our country (June 1990). Twenty-one centers were surveyed (2,399 patients). The most frequent indication for LC was chronic gallstone disease (76.2%). The female population predominated (69.4%). Seven centers always perform the laparoscopic approach. Antibiotic prophylaxis is the rule, and most centers use nasogastric tube and urinary catheterization. Perioperative cholangiography is done selectively. The instrument of choice to dissect the gallbladder is the electrosurgical hook-knife. General anesthesia is preferred (97%). The complication rate was 8.87%. Injury to the bile duct and bowel perforation occurred in 0.25% and common duct stone retention occurred in 0.29% of patients. Mortality rate reached 0.12%. It is our hope that this study will help in defining the situation of LC in developing countries and that it also can serve as a first step in the organization of minimally invasive surgery groups in Mexico.

Adolescent↗

PubMed1992

[Anomalous origin of left coronary artery in pulmonary artery].

We report 2 infants aged 6 months and one year with an anomalous left coronary artery origin treated surgically at our centre with direct aortic reimplantation of the anomalous coronary. Evolution has been satisfactory, with a great improvement of ventricular function. The mitral incompetence and congestive heart failure have disappeared and myocardic perfusion electrocardiographic patterns were corrected. Because of the unfavorable natural course of the disease and the improvement in techniques of coronary revascularization in infants we recommend an early surgical treatment as soon as it be diagnosed. We consider that the most adequate surgical treatment is the direct aortic reimplantation of the anomalous coronary artery.

Abnormalities, Multiple↗

PubMed1988

Inhibition of growth and differentiation of fetal hamster gonads grafted into the adult testis.

A cytomorphological analysis of the effect of adult testes on growth and differentiation of grafted fetal testis or ovaries was performed in hamsters. Fetal gonads, taken at 14 days post-coital age, were grafted for 30 days either under the renal capsule or testicular capsule of scrotal or cryptorchid testes of adult hamsters (weight 115 +/- 23 g). Renal grafts were also performed in males castrated 30 days prior to receiving the fetal gonads. Growth and differentiation of the fetal gonads (testis or ovary) was totally inhibited by the scrotal testis. When the cryptorchid testis was the recipient of fetal gonads, inhibition was correlated inversely with the degree of spermatogenic damage elicited in the cryptorchid testis. No inhibition was observed in fetal gonads grafted under the kidney capsule, nor in castrated, normal or cryptorchid animals. As normal growth and differentiation of both testis and ovary occurred when grafted under the kidney capsule, the inhibitory effect of adult gonads seems to be unrelated to plasma testosterone levels in the host, as levels were undetectable in castrated hamsters and reduced drastically in cryptorchid animals. At the same time, the testicular-inhibiting substance in normal animals did not act at a distance, since its effect was restricted to fetal gonads grafted under the testicular capsule. This inhibitory substance may correspond to the spermatogonial chalone, known to be produced by differentiating spermatogenic cells (mainly spermatocytes and round spermatids in the rat and mouse); these chalones prevent spermatogonial proliferation and, consequently, the critical number of spermatogonia needed to enter meiosis is not attained. It is doubtful if the same substance has the ability to differentiate the fetal ovary or if this effect can be ascribed to a more complex situation involving other testicular peptides of paracrine action and/or locally high levels of androgens.

Animals↗

PubMedDate not supplied

Thoracoabdominal wall repair with glutaraldehyde-preserved bovine pericardium.

Glutaraldehyde-preserved bovine pericardium (GPBP) is evaluated as a bioprosthesis for the reconstruction of surgical defects in the thoracoabdominal wall. The mechanical properties of bovine pericardium preserved at different concentrations of glutaraldehyde were studied. Samples preserved in 0.5% glutaraldehyde showed a significantly higher tensile strength (11.7 +/- 0.8 N/mm2) than samples preserved in 2.5, 5, or 10% (similar to pericardium preserved in normal saline). The percentage of elongation was significantly lower than samples preserved in 1, 2.5, and 5% glutaraldehyde. GPBP at 0.5% was used to repair experimentally induced defects of the abdominal wall (n = 9), chest wall (n = 6), diaphragm (n = 6), and sternum (n = 7). All animals presented adequate tolerance to the material used and no case of infection or rejection of the material was seen in any of the animals. Finally, 0.5% GPBP was used clinically in a series of 40 patients: postincisional abdominal hernia (n = 30), inguinal hernia (n = 8), diaphragmatic hernia (n = 1), and congenital pelvic defect with prolapse of abdominal organs (n = 1). Surgical use showed that GPBP was a very manageable material and long-term results were good in 37 patients with a mean follow up of 18 months (range 5-35 months). Six patients presented seroma formation (all abdominal hernia patients), three of which eventually developed infection and had the GPBP patch removed at 3, 5, and 7 months postoperatively. The rest of the patients presented good scar formation with adequate resistance at the area of implantation. GPBP is a biological material with sufficient resistance to be used surgically in the repair of thoracoabdominal defects. Ideal concentration of glutaraldehyde to be used in the preparation-preservation of the material is 0.5% since higher concentration negatively affect its tensile rupture strength and elongation.

Abdominal Muscles↗

PubMedDate not supplied

[A community program to stimulate smoking cessation].

A community program to stimulate smoking cessation developed on the 1988 World No-smoking Day in the city of Barcelona (Spain) is presented. Participants in this program could make a written commitment to quit, and received support materials by mail. The results are evaluated in a sample of participants: 69% declare having quit on the specified date, and 29% do not smoke after one year.

Adult↗