Search PubMed⌕ Search

Biomedical subjects

L Romero

Publications and source records attributed to L Romero.

At least 91 records · Page 5Linked to original sources

Oncocytoma of the lung.

A tumor diagnosed as an oncocytoma was removed from the lower right lung of a 22-year-old patient. Specimens from the formalin fixed tumor were studied by light microscopy and by electron microscopy. Large numbers of mitochondria were observed in all the tumor cells at the ultrastructural level despite many artefacts due to fixation. The presence of two tumor cell types "typical" oncocytes and "condensed" oncocytes were demonstrated by electron microscopy. This appears to be the second pulmonary oncocytoma in which mitochondrial hyperplaxia has been demonstrated. The tumor was similar to previously reported cases of salivary gland oncocytomas.

Adult↗

[Dose-effect of the administration of ferrous fumarate in aged persons with iron deficiency].

BACKGROUND: Anemia is the most prevalent hematological problem in elderly persons, affecting 14% of the males and 6% of the females of the population over 60 years of age in Mexico City. OBJECTIVE: To determine the effect produced by the prolonged administration of ferrous fumarate in elderly persons with iron deficiency. METHOD: In a population of 178 subjects, aged between 65 to 100 years, iron deficiency was diagnosed in 51 (28.6%), who had serum iron concentrations below 80 micrograms/dL for men and 60 micrograms/dL for women, but only 21 patients (11.8%), accepted to participated in the study. The response to a 6 months oral administration of ferrous fumarate were studied with a daily oral dose of 5 mg/kg of elemental iron. The patients were classified in 3 groups according to the abnormal parameters of iron metabolism (group 1 = 10.9% anemia, group 2 = 28.0% and group 3 = 63.0% anemia). RESULTS: The efficacy of treatment was evaluated by quantification of the changes occurred in serum iron concentrations, hemoglobin, ferritin and transferrin saturation index, at 0, 30, 90 and 180 days of treatment. This study showed that the treatment of oral ferrous fumarate in elderly patients with iron deficiency, produces a quantifiable improvement in measures of iron parameters within 6 months. CONCLUSIONS: The results of this study suggest the usefulness of prolonged treatment with ferrous fumarate in elderly patients with iron deficiency, to avoid therapeutic failure as a consequence of non-compliance as is common in elderly patients.

Age Factors↗

[Surgical resection of a focus of ventricular tachycardia guided by endocardial and epicardial mapping].

We describe a case of a 46 years old female with chagasic heart disease. In one year she presented six episodes of sustained ventricular tachycardia, heart rate 230 beats per minute, morphology of RBBB AQRS -60 degrees, with hemodynamic deterioration that needed electrical cardioversion. She was treated with several antiarrhythmic drugs but not good response was obtained. Programmed electrical stimulation was done and it show three different types of ventricular tachycardia, trough pace-mapping the site of the clinical tachycardia was located in the portion inferior and inferior-posterior of the left ventricle that was confirmed by entrainment. Epicardial mapping was performed in 38 ventricular sites following the modified Harken sketch and the location of the site of outlet was confirmed in the posterior base of the left ventricle, at this point the surgical resection was done with no complication. The results were satisfactory. Eight days later programmed electrical stimulation was done and the ventricular tachycardia could not be induced. Six months afterwards the patient is asymptomatic without medical treatment.

Cardiac Pacing, Artificial↗

[The clinical and electrophysiological characteristics of patients with idiopathic ventricular tachycardia].

Clinical and electrophysiological characteristics in 20 patients with clinical ventricular tachycardia and normal hearts documented by physical examination, echocardiography, and angiocardiography were analysed. There were 11 males and 9 females. All patients had sustained ventricular tachycardia without hemodynamic instability during tachycardia. A right bundle branch block morphology of ventricular tachycardia was present in 14 patients and left bundle branch block morphology in six patients. During electrophysiologic studies, ventricular tachycardia was induced in 10/15 (66%) patients. Intravenous verapamil terminated the ventricular tachycardia in 9/10 (90%) of cases. However oral verapamil not prevented recurrences. Among 14 patients on whom exercise tests were performed, only two had exercise-induced ventricular/tachycardia. Late potentials were positive in 3/14 (21%) cases and one patient died suddenly during exercise without antiarrhythmic drugs.

Adolescent↗

[Atrioventricular and ventriculoatrial conduction in patients operated on for the Wolff-Parkinson-White syndrome].

Over the last decade the surgical treatment of the Wolff-Parkinson-White syndrome has been well accepted. It is important to make an early diagnosis for surgical success. For this purpose we utilized programmed electrical stimulation to assess the functional characteristics of atrioventricular and ventriculoatrial conduction in our post-operative patients. In 55% of the cases we found accelerated nodal conduction. Programmed electrical stimulation correctly identified 90% of successfully treated patients. We did not found any false positive curve, therefore, this method has a high specificity. We concluded that in post-operative patients with the Wolff-Parkinson-White syndrome: 1- There is a high incidence of accelerated nodal conduction and 2- programmed electrical stimulation can correctly identify most of the patients who were successfully treated.

Adolescent↗

[Relation of prolactin with nodular hyperplasia and carcinoma of the prostate].

The relationship between prolactin in NH and prostate carcinoma has several aspects: under normal conditions, prolactin enhances androgens output, increasing the Leydig cell susceptibility to LH. At the prostate level, it increases testosterone binding to the prostate epithelium and stimulates the conversion of testosterone to dihydrotestosterone. On its own, it decreases prostatic protein degradation and increases the DNA synthesis index. With regard to Nodular Hyperplasia, once its hormone dependency is rated, it also appears to be stimulated by high levels of prolactin. The NH cell cultures with human prostate increase their growth, cell division, as well as the DNA synthesis. The aspects of the prolactin-prostate carcinoma interaction involve considering this hormone as a possible carcinogenic agent, emphasizing the existence of high plasma levels of this hormone in individuals with prostate carcinoma, where any androgen excess is considered a major factor at the genesis of this tumour, and prolactin increases indirectly its testicular synthesis. Also, prolactin itself stimulates the growth and development of carcinomatous human cell lines, increasing its effect in the presence of testosterone. For this reason, controlling this hormone levels becomes an element to have into consideration in the treatment and follow-up of these patients; also, the reevaluation of any drug therapy that, besides the initial goal pursued, does not maintain baseline prolactin levels. The association of anti-prolactin drugs has to be understood as a co-adjuvant therapy when there is androgenic deprivation, never as a single treatment.

Animals↗

[Electrophysiologic effect of intravenous propafenone in supraventricular tachycardia].

The electrophysiologic effects of intravenous propafenone were studied in twenty six patients with supraventricular tachycardias. Ten patients (38%) with intranodal reentrance tachycardia common type, and sixteen patients (62%) atrioventricular orthodromic reentrance tachycardia. Propafenone (2 mg/kg intravenously) given over ten minutes period caused termination of the intranodal reentrance tachycardia in 60% of the cases and 50% to the patients with atrioventricular reentrance tachycardia. The antiarrhythmic effects observed are related to the slowing of the conduction velocity and to the prolongation of the refractoriness in the AV node and accessory pathways preventing the reentrance mechanism. The reinduction of the tachycardia was possible in 46% of the patients. This effects was more significative in the group with accessory pathways (50%), and 40% of the patients with intranodal reentrance. The supraventricular tachycardia was inducible by programmed electrical stimulation in 46% of the patients. None of the patients developed side effects to the administration of the propafenone.

Adolescent↗

[Positive exercise test in hypertensive patients correlated with coronary angiography].

With the purpose of evaluate the state of the coronary arteries in hypertensive patients with positive exercise test, 82 patients were selected, 50 male and 32 female with mean age of 56.9 +/- 13.2 years. Angiography was normal in 25 patients thirteen patients had a single coronary arteries narrow of less than 50% and 44 cases with significant coronary arteries lesions of more than 50%. The parameters obtained in the exercise test are not significant for statistic purposes. Systolic hypertension or flat response was more frequent in the group with advanced coronary lesions with a predicted positive value in coronary obstructions of 66 and 75%. We conclude that 70% of hypertensive patients have obstructive coronary lesions of some degree.

Arterial Occlusive Diseases↗

[Surgical treatment of supraventricular tachycardias (Wolff Parkinson White and Occult Kent). Experience at the "Ignacio Chávez" National Institute of cardiology].

We report our initial experience in the surgical section of the accessory pathway in thirteen patients: eight patients with Wolff Parkinson White syndrome and five with accessory pathway functioning only in direction ventricle to atrium (Kent concealed), with recurrent episodes of paroxysmal supraventricular tachycardia with no response to medical treatment. Three of these patients had episodes of auricular fibrillation with interval RR lower than 250 msec and one patient presented syncope. A total of fifteen accessory pathways were sectioned: 7 left lateral, 5 left posterior, one left posterolateral, one right lateral, and another one right anteroseptal. In the same procedure two patients had correction of another heart malformation: one with patent ductus arteriosus and another with and another with atrial septal defect. All patients had successful outcome, one of them needed a second surgery for persistent accessory pathway. We had two post-operatory complications: one mediastinitis and one patient with ectopic auricular tachycardia.

Adolescent↗

[Disorders of the rhythm and conduction in patients operated on for a total correction of tetralogy of Fallot].

The purpose of this paper is to analyze the incidence of arrhythmias and conduction disturbances in 81 patients after total surgical repair of tetralogy of Fallot. The study was done at the National Institute of Cardiology "Ignacio Chávez" from 1974 to 1989. Sixty five patients (78.9%) developed a pattern of right bundle block and ten patients (12.3%) had additional left anterior hemiblock following surgery. Two patients had complete heart block so pacemaker was implanted. The incidence of serious ventricular arrhythmias was found in 11 patients often polymorphic ventricular premature complexes. One case sustained monomorphic ventricular tachycardia. Electrophysiological study demonstrated that it source was the scar of the right ventricle outflow tract. This tachycardia is now under control with specific antiarrhythmic therapy.

Arrhythmias, Cardiac↗

[Rational management of arrhythmias].

Despite the development of better diagnostic techniques and new modes of therapy, management of cardiac arrhythmias is still difficult. The lack of standardization in the indications of each technique has increased the risk of overtreatment and unnecessary cost. This paper describes the minimal requirements necessary for the different techniques and the appropriate information that should be collected from each. A well taken clinical history and a 12-lead EKG give very important information for the decision on when and how to treat.

Arrhythmias, Cardiac↗

[Electrofulguration of refractory supraventricular paroxysmal tachycardias. (Experiences of the "Ignacio Cháves" National Institute of Cardiology].

The purpose of this paper is to report our experience with endocardial catheter ablation in the recurrent episodes of paroxysmal supraventricular tachycardia in ten patients. All cases were referred because previous drug trials had failed to control arrhythmia. In four patients with Wolff Parkinson White syndrome, the ablation was used in the accessory pathway, in five patients in the his bundle region, and one patient in the AV perinodal region. The follow-up ranges from 4 to 15 months. We had a complete success rate of 40% and a partial success in other 40%. We did not have any complications during the procedures.

Adolescent↗

Pathophysiology of experimental nephrotic syndrome induced by puromycin aminonucleoside in rats. I. The role of proteinuria, hypoproteinemia, and renin-angiotensin-aldosterone system on sodium retention.

The pathophysiology of the nephrotic syndrome (NS), characterized by protenuria, edema, sodium retention and hyperlipidemia, is not clear. We studied the role of some systemic factors on sodium retention in an experimental model of NS. NS was induced in rats by a single subcutaneous injection of puromycin aminonucleoside (PA) (15 mg/100 g); control animals received vehicle. All rats were kept in metabolic cages for 24 days (3 days before and 21 days after PA-injection). Urine was collected daily. Blood samples were obtained every day until day 10, and then every other day up to the end of the study. The rats showed the following alterations after PA injection: a) a rise in serum angiotensin converting enzyme activity (ACEA) and plasma aldosterone (PAldo) at day 1; b) a rise in urinary aldosterone (UAaldoV), azotemia and sodium retention at day 2; c) massive proteinuria (UProt) and decrease in plasma angiotensinogen concentration (PAC) at day 4; d) increases in plasma renin activity (PRA), plasma renin concentration (PRC) and serum creatinine as well as hypoproteinemia, hypercholesterolemia, hypertriglyceridemia, ascitis and edema at day 5; e) increase in urine volume at day 6. PAldo became normal at day 7; urine sodium (UNaV), PRA and PRC at day 8; UAldoV at day 9; serum urea and ACEA at day 10; urinary volume at day 11; PAC, serum total protein and creatinine at day 12. The edema disappeared at day 11. UProt, hypercholesterolemia and hypertriglyceridemia persisted, though they decreased substantially by the end of the study (day 21). Light microscopy studies revealed normal glomerular morphology, but electron microscopy showed fusion of podocytes before proteinuria. These data suggest that: a) sodium retention was not a consequence of proteinuria or hypoproteinemia; b) sodium retention seems non-related to renin secretion, but may be partially mediated by a fall in glomerular filtration rate or by an increased tubular resabsorption secondary to other factors; c) the increase in PAldo, UAldoV and ACEA are non-related to renin secretion: all occurred before PRA rose; d) water retention, increase in PRA and PRC, hypercholesterolemia and hypertriglyceridemia are secondary to the hypoproteinemia.

Animals↗

The educational opportunities in a departmental program of health care for the homeless.

Persons who live on the streets and are homeless present many challenges to providers of health care. This paper describes a 14-year ongoing project in the Department of Family, Community, and Emergency Medicine at the University of New Mexico School of Medicine. This small clinic started in an inner-city rescue mission and subsequently has progressed to a much larger health care project for the homeless. Experience in this setting demonstrates that such a site can provide service to the homeless, while at the same time providing educational experiences for medical students and residents and an opportunity for academic research. This project can be duplicated in any academic medical center to provide both service and education.

Education, Medical, Continuing↗