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Biomedical subjects

C Romero

Publications and source records attributed to C Romero.

At least 73 records · Page 4Linked to original sources
PubMed1995

Further insights on chromosomal pairing of autopolyploids: a triploid and tetraploids of rye.

Chromosomal pairing of one triploid and three tetraploid plants of rye, Secale cereale, was analyzed by electron microscopy in surface-spread prophase I nuclei and compared with light microscopic observations of metaphase I cells. Prophase I is characterized by: (i) the weak alignment showed by the three or four unsynapsed or partially homologous synapsed axes; (ii) the low number of pairing partner switches (PPSs) displayed by both trivalents and quadrivalents; and (iii) the existence of complex multivalents in which up to 13 chromosomes in the triploid and 22 chromosomes in the tetraploids were involved. However, only few heterologous chromosomal associations were maintained at metaphase I. The results obtained are discussed under the assumptions of the random end pairing model with some modifications.

Chromosome Banding↗
PubMed1995

Evaluation of PCR and indirect enzyme-linked immunosorbent assay on milk samples for diagnosis of brucellosis in dairy cattle.

A study was performed to evaluate the previously described PCR (C. Romero, C. Gamazo, M. Pardo, and I. López-Goñi, J. Clin. Microbiol. 33:615-617, 1995) for the diagnosis of brucellosis in dairy cattle. Milk samples from 56 Brucella milk culture-positive cattle and from 37 cattle from Brucella-free herds were examined for Brucella DNA by PCR and for specific antibodies by an indirect enzyme-linked immunosorbent assay (ELISA). The specificities of both tests were 100% when testing the milk samples from Brucella-free cattle. The milk samples from 49 infected cattle were positive by PCR (87.5% sensitivity), and 55 were positive by ELISA (98.2% sensitivity). A PCR-positive sample was negative by ELISA, and 7 ELISA-positive samples were PCR negative, yielding an observed proportion of agreement of 0.91 for the two tests. Although the results suggest that ELISA is a better screening test than PCR, the combined sensitivity of the two assays was 100%, and their simultaneous application could be more useful than one test alone for a rapid screening of brucellosis in dairy cattle.

Animals↗
PubMed1995

Specific detection of Brucella DNA by PCR.

A PCR assay with primers derived from the 16S rRNA sequence of Brucella abortus was developed. Nine different combinations between six primers were tested. One pair of primers, which amplified a 905-bp fragment, was selected. As little as 80 fg of Brucella DNA was detected by this method. DNAs from all of the representative strains of the species and biovars of Brucella and from 23 different Brucella isolates were analyzed and yielded exclusively the 905-bp fragment. No amplification was detected with DNAs from 10 strains phylogenetically related to Brucella spp., 5 gram-negative bacteria showing serological cross-reactions with Brucella spp., and 36 different clinical isolates of non-Brucella species. Only Ochrobactrum anthropi biotype D yielded a PCR product of 905 bp, suggesting a closer relationship between Brucella spp. and O. anthropi biotype D. The specificity and high sensitivity of the PCR assay may provide a valuable tool for the diagnosis of brucellosis.

Base Sequence↗
PubMed1994

Isolated renal mucormycosis in two AIDS patients.

Two cases of mucormycosis in patients with exclusively renal involvement and advanced HIV infection are reported. In both cases the clinical course was relatively benign; in one case a tendency towards regression with no specific treatment was observed, and in the other case the infection resolved after nephrectomy and antifungal therapy. Renal mucormycosis should be considered in the differential diagnosis of diffuse renal enlargement in HIV-infected patients.

AIDS-Related Opportunistic Infections↗
PubMed1994

Evaluation of the sensitivity of RT-23 purified protein derivative for determining tuberculin reactivity in a group of health care workers.

Since 1958 the World Health Organization (WHO) has recommended the use of RT-23 (2 tuberculin unit [TU] purified protein derivative [PPD]) instead of the standard 5 TU PPD to establish the prevalence of tuberculosis (TB) around the world. Before starting a hospital program to control the transmission of TB among health care workers at the National Institute of Nutrition (Mexico City), we compared the tuberculin product commonly used in Mexico (RT-23) with that used in the United States (5 TU PPD). In this trial the Mantoux test was performed on 80 health care workers from various areas of the hospital: 5 TU PPD and RT-23 were simultaneously inoculated in the left forearm and in the right forearm, respectively. The test results for both tuberculin products were read 72 hours later. When a 10-mm induration was used as the cutoff for reactivity, the specificity with use of RT-23 was 100%, but the sensitivity was only 57%. However, when a 5-mm induration was used as the cutoff, the sensitivity with use of RT-23 was 90%. Because of these findings, we advise that every country using RT-23 either consider changing the cutoff for reactivity or consider using 5 TU PPD for reassessment of the data on the incidence and prevalence of TB that were obtained with use of RT-23 (the product recommended by WHO).

Adult↗
PubMed1994

[Size reduction of uterine myomas with monthly administered leuprolide acetate].

Six patients with symptomatic leiomyomata uteri and in whom surgical treatment was indicated received, during 3 months, intramuscular leuprolide acetate, 3,75 mg monthly, in order to 1) achieve a reduction of myomata size and 2) recover an anemic patient before surgery. In every patient, amenorrhea was induced since the second month of treatment. A significant decrease of myomas sizes was achieved. The reduction of the volume of the largest myoma in each case, varied between 51% and 77% (x = 60% +/- ES 4,3) LH and estradiol plasma levels diminished significantly and FSH did not changed in response to treatment. Side effects were well tolerated. Hot flashes were present in all patients, headaches in 2 and loss of strength in 2. Surgery was accomplished after 3 months of treatment. Myomectomy was performed in 5 cases and total hysterectomy in 1. Uterine shrinkage and the period of amenorrhea induced by Lupron-depot facilitated hysterectomy and myomectomy techniques and the recovery of one patient with a severe anemia.

Adult↗
PubMed1994

Type II pneumocytes revisited: intracellular membranous systems, surface characteristics, and lamellar body secretion.

BACKGROUND: Type II pneumocytes, the producers of pulmonary surfactant, have been extensively studied during the last 20 years because of the importance of their metabolism in lung function and integrity. The ultrastructural studies of the 1970s and 1980s have shown that these cells present unique elements. EXPERIMENTAL DESIGN: In this work, we used thin-section, freeze-fracture, and fracture-flip electron microscopy techniques to obtain new information on the ultrastructural peculiarities of isolated rat type II pneumocytes, focusing our study on the intracellular membranous systems and their interrelationships and the microanatomy of their plasma membrane during secretory process. RESULTS: In thin-sections of pneumocytes postfixed with osmium tetroxide and potassium ferricyanide, we observed that lamellar bodies (LBs) are usually connected to membranes of the endoplasmic reticulum, and seem to emerge and grow from them. Unusual connections between the endoplasmic reticulum and mitochondria were detected, as well as numerous "bar-like structures" (BLSs), most of them in the early stages of development and often generating from the nuclear membrane. Membranes of the smooth endoplasmic reticulum that closely follow the outlines of mitochondria also appear to be the origin of some BLSs. Possible transition forms, BLS--LB, were also detected, although they were rare. New images of the surface of the pneumocytes and its changes during LB secretion showed a segregation and clearing of membrane particles at the areas of LB extrusion. CONCLUSIONS: We propose that LBs can originate directly from membranes of the endoplasmic reticulum or from BLSs. An indirect participation of mitochondria appears possible. The plasma membrane of pneumocytes displays structural changes associated with the secretion of LBs as visualized by a redistribution of intramembrane and surface particles.

Animals↗
PubMed1993

Effect of dimethylthiourea in phosphatidylcholine biosynthesis by rat lung during reversible endotoxic shock.

A rat model of endotoxic shock was used to evaluate the effects of dimethylthiourea, a putative hydroxyl radical scavenger, in the alterations of lung phosphatidylcholine biosynthesis found during endotoxemia. Treatment of rats with dimethylthiourea, just before lipopolysaccharide injection, resulted in a decreased lipid peroxidation and an increase in phosphatidylcholine biosynthesis, although it did not prevent the body weight loss or the increase in lung weight and lung protein content associated with the lung injury induced by lipopolysaccharide. Our results suggest that phosphatidylcholine biosynthesis is impaired by processes in which hydroxyl radicals are implicated, although other oxygen free radical species, not removed by dimethylthiourea, can be also involved in lipopolysaccharide mediated lung injury.

Animals↗
PubMed1993

[Importance of prolactin isoforms on ovary function in hyperprolactinemic women].

Gel filtration chromatography in Sephadex G-100, was used to analyse the molecular heterogeneity of prolactin (PRL) in serum from seven hyperprolactinemic women. Chromatographic patterns from samples obtained from four women with hyperprolactinemia and normal menstrual cycles showed a predominance of big-big PRL (79%). In contrast, three women with hyperprolactinemia and amenorrhea presented a chromatographic pattern with predominance of little PRL (69%). The results suggest that the molecular heterogeneity of PRL found is associated with menstrual cycles disorders and hence with ovarian function. Normal ovarian function in hyperprolactinemic patients seems to be associated to increased levels of big-big PRL and altered ovarian function to high level of little PRL.

Amenorrhea↗
PubMed1993

[Usefulness of transvaginal Doppler color in ovarian neoplasms diagnosis].

The vascular resistant evaluation by Doppler waveform is a method used in clinic and research. The neoplastic malignant has an increased growth with an increased amount of neomalignant vessels. The presence of these vessels produce an increase of the transversal section area from the tumoral vascular system, therefore there is a decrease in the vascular resistance. The main objective of this work is to show the usefulness of Doppler waveform as predictor factor of malignity in ovary tumors. Eighteen patients with tumoral mass in the ovary were studied. They were between 21 and 67 years old (mean = 43). The tumoral volume and the flow resistance of blood vessels which irrigated those tumoral mass were evaluated by transvaginal ultrasound with color and pulsed Doppler. The pulsatility index (SD/media) was used. The Chi cuadrado test was used to evaluate the results. The results show the presence of six malignant tumors, three of them with low malignicity and the presence of twelve benign tumors. The age of the patients between both groups (malignant and benign tumors) were significant different (40.7 versus 52 years old, p < 0.001). The mean tumoral volume was 65 ml, with a range of 17 to 225 ml in the group of patients with benign tumors and the mean tumoral volume from patients with malignant tumors was 951 ml with a range of 141 to 3142 ml. The difference in the tumoral in both groups was significative with p < 0.001.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Transesophageal echocardiographic monitoring of percutaneous mitral balloon valvulotomy.

This study was designed to evaluate the usefulness of performing transesophageal echocardiography (TEE) during percutaneous mitral balloon valvulotomy (PMBV). TEE was performed in 35 consecutive patients with symptomatic severe mitral stenosis during PMBV (group A). Another group of 27 patients with mitral stenosis who underwent PMBV without TEE was used for comparison (group B). TEE was most helpful in guiding transseptal puncture, aiding in proper positioning of the balloon during the dilatation procedure and enabling early detection of complications. The results show that PMBV when aided by TEE has a tendency to decrease the frequency of significant mitral regurgitation without compromising the final mitral valve area. TEE decreased the x-ray exposure time and was well-tolerated. Thus, TEE provides information that makes this interventional catheterization procedure safer and easier to perform.

Cardiac Catheterization↗
PubMed1992

[Sexually transmitted microorganisms and immunoglobulins in the amniotic fluid in mothers who carry sexually transmitted diseases].

Fetal behaviour as an intrauterine patient is unknown. In the diagnosis of sexually transmitted diseases (STD) and in the criteria for treatment only the mother is considered leaving the fetus out. The presence of immunoglobulin M in the amniotic fluid is an indicator of fetal infection and could allow an accurate diagnosis of fetal disease or treatment, if the measurement is related to the presence or absence of organism in the amniotic fluid. In this way, the study of fetal behaviour under these conditions could be done. The objective of this research was to determine the presence of STD organism in the amniotic fluid of the STD infected pregnant women and to evaluate the prevalence and evolution of these pathologies in the fetus. No STD organism, nor immunoglobulin M were found in the 13 samples of amniotic fluid (8 pre and 5 post-treatment) of infected pregnant women. The presence of microorganisms and its relation to immunoglobulin M was not observed. More cases are needed to arrive to a conclusion regarding fetal immunology and to a better understanding of antibacterial properties of the amniotic fluid. We concluded that no contamination in the amniotic fluid or fetal infection was found in pregnant women with STD.

Amniotic Fluid↗
PubMed1992

[The gestrinone (R-2323) treatment of endometriosis].

Results of medical treatment with gestrinone are evaluated in 29 women with minimal (10), mild (9) and moderate (7) endometriosis. After a diagnostic laparoscopy, patients started gestrinone 2.5 mg/day 2 times a week per 6 months. Clinical evaluations and blood samples were performed at the end of the ist, 3rd and 6th month of treatment. A second look laparoscopy, in 26 out of the 29 patients, was performed within a month after discontinuation of the drug. Nineteen patients (73.1%) showed a diminishing in endometriosis score. Moreover, 2 of them presented with a normal pelvis at the time of the 2nd laparoscopy. Overall post treatment scores were significantly lower than pre treatment scores (6.1 +/- 6.9 versus 11.3 +/- 10.2 respectively, p < 0.025). Nineteen out of the 26 patients had amenorrhea, most of them (18) since the second month of treatment. Nineteen patients presented with dysmenorrhea at the beginning of the treatment and in 13 of them it disappeared during the first 3 months of the drug. Reversible elevation in serum transaminases was observed in 4 patients. Red blood cells count and platelet concentration increased at the end of the treatment. A clear pituitary suppression to basal levels was seen. No significant changes on androgen levels were appreciated. Seven patients achieved a spontaneous pregnancy, out of 22 that desired fertility (31.8%), all of them were clinical pregnancies.

Adult↗
PubMed1992

CT, myelography and CT-myelography in the evaluation of common cervicobrachial neuralgia.

The CT technique used to explore intervertebral discs and foramina is described, as are the CT signs of nucleus pulposus (NP) herniation and cervical degenerative lesions. CT with intravenous contrast injection is the most efficient and easiest method to diagnose a radicular compression of discal or degenerative origin. The advent of high-resolution contrast CT will probably make obsolete the use of contrast media. CT measures the width of the vertebral canal, but it does not evaluate the repercussions on the spinal cord of compression caused by NP herniation or osteophytosis: only CT-myelography or, better, MRI can make this evaluation. Conventional CT scans are sometimes inadequate when exploration is hampered by superimposition of the shoulders (C6-C7 and more often C7-T1), when the scanner is of poor quality or when it is misused. Myelography and CT-myelography can then be utilized to resolve the problem posed by C7 or C8 cervicobrachial neuralgia (CBN). CT makes it possible to exclude most of the causes of non-discal CBN in the extradural spaces (e.g. bone tumour, neurinoma, vertebral vascular malformation, paravertebral expansive process, apical lung tumour). The search for an intradural cause (extra- or intramedullary tumour) rests on myelography, CT-myelography and MRI.

Adult↗