Search PubMed⌕ Search

Biomedical subjects

C Romero

Publications and source records attributed to C Romero.

At least 91 records · Page 5Linked to original sources
PubMed1991

First clinical implantation of the BCM 3.5 ventricular assist device (VAD).

We report on the first human implantation of the BCM 3.5 ventricular assist device in a 46-year-old man suffering from terminal stage cardiomyopathy. The circulatory support was used as a bridge to heart transplantation. The patient was in cardiogenic shock and was on assisted circulation for 18 days after which he underwent cardiac transplantation. While receiving support from the ventricular assist device, the patient's condition improved remarkably and 50 days after transplantation he was discharged from hospital. We give a detailed description of the surgical technique, with special emphasis on the procedures for air extraction. We describe the evolution of the hemodynamic status before and after implantation. Final inspection of the device and cannulae after removal showed no thrombi and only small fibrin deposits in the membrane-wall junction.

Cardiomyopathy, Dilated↗
PubMed1991

[The treatment of chronic stable angina with isradipine. A cooperative Latin American study].

In order to study the efficacy and tolerance of isradipine, a new Ca++ antagonist for the treatment of stable chronic angina, a multicentric cooperative study was carried out in eight Latin American countries (Argentine, Chile, Colombia, Ecuador, Mexico, Peru, Uruguay and Venezuela), which included 169 patients (60% men and 40% women), average age 62.6 +/- 9.7. Patients with more than 4 biweekly anginal crisis were accepted, with one or more of the following inclusion criteria: coronariographic evidence of obstruction greater than 60% in one or more vessels, IAM history, positive scintigraphy and positive effort test. The trial was single-blind, with placebo during the admission phase (2 weeks) and active treatment for 12 weeks. isradipine was administered in increasing doses of 2.5, 5, and 7 mg thrice a day, according to the presence or absence of anginal crisis. It was observed that the average frequency of weekly pains decreased from 8.2 +/- 7 under placebo to 6.3 +/- 7.5 under isradipine at low doses, and to 2.0 +/- 2.0 (p less than 0.001) under maximum doses. TNT intake decreased parallel also in a significant way. At the end of the trial, 37% of patients had become asymptomatic, and angina had reduced to less than two crisis a week in 33%. A clear relation doses-effect was observed. There was no alteration in laboratory exams neither in ECG. Seven patients had complications derived from the evolutional course of disease (2 IAM, 5 unstable angina and one sudden death). Adverse events were relatively frequent and the majority derived from vasodilator effect (tibial oedema 37%, flushing 17%, headache 23%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Adrenoleukodystrophy. Value of contrast-enhanced MR imaging.

In its early stage adrenoleukodystrophy (ALD) is characterized by hypodensity at CT and signal abnormalities at RMI (low-intensity signal on T1-weighted sequences, high-intensity signal on T2-weighted sequences) in the white matter of the parieto-occipital region and the splenium of the corpus callosum. These CT and RMI abnormalities are suggestive of ALD in children with progressive alteration of the superior brain functions, but they are not specific of the disease. The authors present two cases of ALD and underline the almost pathognomonic value of contrast-enhanced ribbons found at the periphery of low-intensity signal plaques after gadolinium injection. These areas of blood-barrier disruption on a background of inflammation and active demyelination appear, on T2-weighted sequences, as ribbons of low-intensity signal within plaques of high-intensity signal. MRI is also superior to CT in detecting abnormalities located in the posterior fossa, notably lesions of the auditory fibres.

Adrenoleukodystrophy↗
PubMed1989

Uterine cavity and the location of IUDs following administration of meclofenamic acid to menorrhagic women. A pilot study.

The relationship between the uterus and the IUD was studied selectively with hysterosalpingograms in 18 menorrhagic women previously treated with Meclofenamic acid (M Ac.), a well known anti-inflammatory drug. Major anomalies (embedding, perforation, rotation) were found in 28.6% of those patients who responded positively to M Ac. In contrast, major anomalies were found in 63.6% of those patients who responded negatively to the drug. It is proposed that the negative response to M Ac. might be due to severe macroscopic disturbances of the uterine wall-IUD relationship. The degree of response to M Ac. might contribute to the decision to remove the IUD from menorrhagic women. In addition, 84.7% anomalies (deformities, embedding, perforation) in the uterine-IUD relationship were found in 13 women with a T-shape IUD device. The fact that those anomalies are related to the tip of the horizontal arm justifies future studies using shortened arms to diminish hypermenorrhea induced by T-shape devices or attempts to use IUDs which do not have the conventional plastic frame, as in the Cu-Fix IUD which has been mentioned as particularly useful to prevent bleeding side effects and pain induced by conventional IUDs. The Cu-Fix IUD consists of 6 sleeves made of pure (99.99%) copper, each sleeve with a length of 5 mm and an outer diameter of approximately 2.2 mm, threaded on surgical 00 monofilament polypropylene (ProleneR, Ethicon). The total area of exposed copper is approximately 390 mm2. The sleeves are prevented from sliding off the suture by 2 smaller copper tubules crushed on the thread in both ends of the IUD structure. This thread-type, copper-bearing device has been designed to overcome the most common IUD-related problems, bleeding and pain.

Adolescent↗
PubMed1989

HLA class I gene expression on human primary tumours and autologous metastases: demonstration of selective losses of HLA antigens on colorectal, gastric and laryngeal carcinomas.

The expression of HLA class I antigens was studied in 99 primary tumour (colorectal, gastric and laryngeal carcinomas) and 57 autologous metastases using immunohistological techniques and monoclonal antibodies against class I monomorphic determinants, HLA-B isotypic determinants and HLA polymorphic determinants. Fourteen per cent of colorectal, 9.6% of gastric and 20% of laryngeal carcinomas completely lacked class I molecules. Selective losses of HLA-B antigens were also detected in 8.8, 3.4 and 5.8% of these tumours respectively. Taking into account complete and selective loss of HLA-B the average alteration in the class I molecules expression totalled 21%. The comparison of class I expression between primary tumours and autologous metastases showed differences in 24% of the patients. These differences consisted mainly in a decrease of class I expression by metastases. Nevertheless, four types of divergence were detected in laryngeal carcinomas, namely: +/-, +/+, -/+, -/-. In addition, a clear correlation between degree of differentiation and class I expression was observed in laryngeal tumours. Finally, when class I gene RFLPs were compared with DNA from 15 tumours and autologous normal mucosa or peripheral lymphocytes, no differences were detected between these samples.

Blotting, Southern↗
PubMed1989

[Echographic imaging of absence of follicular rupture. Endocrinologic aspects].

Since Jewelewicz in 1975 first described the luteinization of an unruptured follicle (LUF), clinical evidence for the importance of this syndrome has been given by various groups of investigators. Luteal phase of 14 cycles with ultrasound evidence of unruptured follicles were studied with plasmatic determination of levels of FSH, LH, prolactin, 17 B estradiol and progesterone each one day. Two groups were defined. One, with "ovulatory ranges" of progesterone, probably LUF syndrome and another, with "anovulatory levels", probably follicular cysts.

Estradiol↗
PubMed1989

[In vitro fertilization program. Preliminary results].

Three infertile couples were submitted to in vitro fertilization and uterine embryo transfer (IVF+ET) and 7 to in vitro fertilization and pronuclear stage tubal transfer (IVF+PROST). In order to programmed menstruation Norethisterone, 10 mg daily, were administered during the cycle preceding the one of controlled ovarian hyperstimulation. In order to inhibit endogenous production of FSH and LH, leuprolide acetate, a Gn-RH agonist, was injected subcutaneously 1 mg daily during 6 days and 0.5 mg fowardly from the luteal phase of the cycle proceeding the one of hyperstimulation until the day of HCG administration. To achieve superovulation pure FSH (Metrodine), HMG (Pergonal) and HCG (Endocorion) were used. Oocyte retrieval was performed through transvaginal puncture under ultrasonographic control. For oocyte and embryo identification and classification, spermatozoa separation and capacitation and gamete insemination and incubation procedures habitual techniques were employed. Pronuclear embryo tubal transfer was performed through a laparoscope 17 hours after insemination and embryo transfer to the uterine cavity after 48 hours. Nine of 10 patients responded to gonadotrophin hyperstimulation and were submitted to ovarian puncture. 69 oocytes (7, per patient) were obtained, 59 (81.15% of which were mature. 74.55% of the inseminated oocytes fertilized. Two patients got pregnant: one, submitted to IVF+PROST, presently has a multiple pregnancy with triplets and the second, submitted to IVF+UT, had a missed abortion at 8 weeks of pregnancy.

Adult↗
PubMed1988

Speckle correlation technique to determine roughness in the dermatologic interval.

A non-invasive method is proposed to determine human skin roughness. The technique is based on measurement of the correlation between two field distributions scattered by a metallised triafol (cellulose acetate foil) replica of the epidermal area to be analysed. The two speckle patterns are produced from the same rough surface illuminated by two coherent plane waves (He-Ne laser) under two slightly different angles. The accuracy of the method is highlighted by measurements made on a set of standard samples with roughnesses previously determined by mechanical profilometry. Analysis of the results indicates a precision of around 10%, and an applicability within the interest range of very rough surfaces in excess of 4-5 microns.

Humans↗
PubMed1988

Phenotypic and genetic analysis of HLA class I and HLA-DR antigen expression on human melanomas.

Class I and HLA-DR antigen expression were studied with histochemical techniques involving monomorphic monoclonal antibodies in 49 cases of human malignant melanomas, 20 primary and 29 metastatic. A large percentage (90%) of primary melanomas were positive for HLA class I, while those primary lesions showing lowest levels of class I antigen expression were at the upper end of the range of invasiveness and possessed a higher metastatic potential. Expression of HLA-DR molecules on primary melanomas was low (25% of all cases) and HLA-DR-positive melanomas were among the most aggressive. In metastatic melanomas, HLA class I expression was less common than in primary lesions. The lowest percentage of cases positive for HLA class I was found for cutaneous metastases. HLA-DR molecules were more frequently expressed by lymph node metastases than on primary melanomas. The comparison of the expression of HLA class I and HLA-DR molecules by primary melanomas and their autologous metastases revealed a high degree of heterogeneity. Class I genes were further studied by Southern blot assays. No differences were found in restriction fragments for class I genes among 4 melanomas and their autologous lymphocytes, 2 of which were positive and 2 negative for class I expression.

Blotting, Southern↗
PubMed1987

Late luteal phase administration of RU486 for three successive cycles does not disrupt bleeding patterns or ovulation.

RU486, a 19-nor steroid, binds with high affinity to the receptors for progesterone and glucocorticoids, blocking the actions of these hormones on their target tissues. We conducted studies to determine whether RU486 administered at the end of the luteal phase would disturb the menstrual rhythm, ovulation, or hormonal parameters in the treatment and post-treatment cycles. The first study was done in six surgically sterilized women during two consecutive cycles. RU486 [17 beta-hydroxy-11 beta-(4-dimethylaminophenyl)17 alpha-(1-propynyl)estra-4,9-dien-3-one; 100 mg/day] was given for 4 consecutive days, commencing on days 23-27 of the first cycle. Menstrual bleeding occurred by the second day of RU486 administration in all women and was indistinguishable from their usual bleeding pattern. The onset of this bleeding was advanced by RU486 administration, since it entailed shortening of the luteal phase with prolongation of the following follicular phase. Serum LH, FSH, estradiol, and progesterone levels were normal in five of the six women in both the treatment and posttreatment cycles. The second study was conducted in 10 women who were not exposed to the risk of pregnancy. RU486 (100 mg/day) was given for 4 consecutive days, commencing 4 days before their expected menses for 3 successive cycles, preceded and followed by 2 placebo-treated cycles. Bleeding patterns were indistinguishable during the RU486 and placebo cycles. Late luteal phase administration of RU486 consistently produced menstrual bleeding within 1-3 days of drug administration. Daily early morning urinary LH excretion in 6 women and estrone glucuronide and pregnanediol glucuronide excretion in 5 women during both placebo and RU486 cycles were consistent with luteinization, suggesting ovulation and appropriate corpus luteum function. We conclude that RU486 has no major effect on menstrual cycle events if given at the time of the natural progesterone withdrawal that occurs before menses in nonpregnant women.

Adult↗
PubMed1987

Thyroid hormone profile in dairy cattle acclimated to cold or hot environmental temperatures.

Milk yields and the circulating profile of T4, T3 and rT3 were assessed during three different seasons of the year, in first trimester lactating (L) and in dry (D) multiparous holstein cows acclimated to distinct weather conditions. Within the thermoneutral zone (18-28 degrees C; 40-60% RH) and regardless of their geographical location, the thyroid hormone profile in all L-cows (n = 50) resembled the so-called euthyroid sick syndrome (T4, 43.7 +/- 7.7 nmol/l; T3, 1.31 +/- 0.10 nmol/l and rT3, 0.52 +/- 0.08 nmol/l). In both groups of animals the T3/T4 molar ratio was similar within the entire range of climates encompassed in the study. However, both groups exhibited a significant shift in the T3/rT3 molar ratio during cold (10 degrees C; 50%) or hot-dry (34 degrees C; 40%) weather conditions. This shift reaches maximum values (L, 6.5 +/- 1.2; D, 7.9 +/- 1.0 nmoles/l) under hot-humid conditions (28-42 degrees C; 60-90%). The relative increase of T3 levels from comfortable to cold or hot environmental temperatures, was significantly higher in L and D animals (30 vs 12%, respectively). Furthermore, only L-cows exhibited a significant decrease in the rT3/T4 molar ratio during either type of thermoregulatory demands, as well as a significant increase of T4 values under heat-acclimation. These results suggest that heat-acclimation in dairy cattle does not depress thyroid gland activity, and lend further support to the notion that adaptive thermoregulatory mechanisms in homeothermic vertebrates, involve adjustments in the peripheral monodeiodinative pathways of thyroid hormones.

Acclimatization↗
PubMed1986

Prediction and detection of ovulation by the measurement of urinary pregnanetriol-3 alpha-glucuronide. A multicentre study.

The urine excretion pattern of pregnanetriol 3 alpha-glucuronide (PT-3G) throughout the menstrual cycle in 26 normal ovulating women was evaluated in a multicentre study. The concentration of PT-3G was measured by radioimmunoassay in daily samples of early morning urine (EMU) from 20 women for three consecutive cycles and from 6 women who conceived during the period of study. PT-3G was also measured in 24-h urine samples from 5 additional women. The peak of urine LH was used as a reference point for ovulation (Day 0). The EMU concentration of PT-3G in the follicular phase of 60 normal ovulatory cycles was 5.10 mumol/l +/- 0.11 (arithmetic mean +/- SE). The first PT-3G defined rise (CUSUM analysis) occurred during the late follicular phase (Days -3 to 0) with a PT-3G maximum excretion (9.69 mumol/1 +/- 0.55) on Day 0, whereas a PT-3G excretion peak occurred during mid-luteal phase (Days +5 to +9). The overall PT-3G excretion during the luteal phase (8.06 mumol/1 +/- 0.17) was significantly higher than that of the follicular phase (P less than 0.001). A further sustained increase in PT-3G excretion was noted after day +11 in the conceptional cycles. The 24-h excretion profile of PT-3G was similar to that obtained in EMU samples. No inter-centre significant variation was noticed in terms of PT-3G concentration values. The results were interpreted as demonstrating that the PT-3G excretion profile throughout the cycle exhibits a close resemblance to that of serum 17-OH progesterone. The data also indicates that although the immunoanalytical measurement of this urine steroid metabolite does not give an early sign for the occurrence of ovulation, it can be used for both the immediate prediction and the detection of ovulation.

Adolescent↗
PubMed1986

Effects of different proportions of carbohydrates, polysaccharides/monosaccharides, and different fibers on the metabolic control in diabetic rats.

Recent findings have suggested that diets with a high level of carbohydrates may impair the metabolic control of diabetes mellitus in humans. Moreover, other investigations have indicated that if the simple sugar content is increased in order to attain a proportion of polysaccharides/monosaccharides equal to 1, then neither the blood glucose nor the lipidic response show any change. We have studied the effect of increasing carbohydrates in the diet (59% v 82%), while maintaining cereal fiber levels constant (30%) and replacing cereal fiber in high carbohydrate diets by guar gum (30%) and lentil-derived leguminous fiber (30%) on the metabolic control of streptozotocin-induced diabetic rats. A study with different diets was performed for 3 weeks. An increase of carbohydrates in the diet produces an increase in the HbA1 concentration (1.9% v 3.9%, P less than 0.01) and in serum triglyceride levels (98.75 +/- 22.09 mg/dL v 144.50 +/- 3.52 mg/dL, P less than 0.05). Total cholesterol and HDL-cholesterol levels remained unchanged. The increase does not occur if the cereal fiber is replaced by lentil-derived leguminous fiber. In a second experiment, we substituted 50% of the complex carbohydrates in diets with 80% carbohydrates by glucose. Blood glucose, triglycerides, and HbA1 levels rose significantly in the four groups of rats that received diets containing 50% carbohydrates in glucose form. In addition, a test meal was carried out on day 19, consisting of 2.5 g of food/kg of wt. The maximum increase in blood glucose and the area below the glucose curve response was also significantly higher in the four groups of rats who received glucose in their diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗