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I Rodríguez

Publications and source records attributed to I Rodríguez.

At least 73 records · Page 4Linked to original sources
PubMed1996

Effects of physical exercise on some parameters of bone metabolism in postmenopausal women.

This study was performed on 19 postmenopausal female volunteers in a period of five months of moderate physical exercise in order to examine beneficial changes in muscle strength and flexibility as well as changes in sex hormone binding globulin (SHBG) and other parameters related to bone metabolism. While SHBG decreased significantly (from 56.0 +/- 20.0 to 43.9 +/- 16.1 nM, P = 0.009) phosphorus and urea increased (from 2.8 +/- 0.4 to 4.0 +/- 0.5 mg/dl, P = 0.00006 and from 32.1 +/- 9.4 to 42.3 +/- 11.0 mg/dl, P = 0.03, respectively). These changes were accompanied by significant increases in muscle strength and flexibility. Other parameters such as alkaline phosphatase and calcium did not change significantly during the study. Plasma levels of SHBG were negatively correlated with phosphorus. As higher SHBG has been related to increased bone loss in older women, we conclude that moderate physical activity is an effective means to preserve bone loss in postmenopausal women.

Alkaline Phosphatase↗
PubMed1995

Cis-regulation of achaete and scute: shared enhancer-like elements drive their coexpression in proneural clusters of the imaginal discs.

The pattern of bristles and other sensory organs on the adult cuticle of Drosophila is prefigured in the imaginal discs by the pattern of expression of the proneural achaete (ac) and scute (sc) genes, two members of the ac-sc complex (AS-C). These genes are simultaneously expressed by groups of cells (the proneural clusters) located at constant positions in discs. Their products (transcription factors of the basic-helix-loop-helix family) allow cells to become sensory organ mother cells (SMCs), a fate normally realized by only one or a few cells per cluster. Here we show that the highly complex pattern of proneural clusters is constructed piecemeal, by the action on ac and sc of site-specific, enhancer-like elements distributed along most of the AS-C (approximately 90 kb). Fragments of AS-C DNA containing these enhancers drive reporter lacZ genes in only one or a few proneural clusters. This expression is independent of the ac and sc endogenous genes, indicating that the enhancers respond to local combinations of factors (prepattern). We show further that the cross-activation between ac and sc, discovered by means of transgenes containing either ac or sc promoter fragments linked to lacZ and thought to explain the almost identical patterns of ac and sc expression, does not occur detectably between the endogenous ac and sc genes in most proneural clusters. Our data indicate that coexpression is accomplished by activation of both ac and sc by the same set of position-specific enhancers.

Animals↗
PubMed1993

A serological survey and review of clinical Lyme borreliosis in Spain.

A serosurvey for Lyme disease was conducted by the National Reference Center for Microbiology in Spain. All serum specimens received from patients with erythema migrans (EM), arthritis, and cardiac and neurological disorders were tested for antibodies to Borrelia burgdorferi. Sera from 499 patients were tested. Of these patients, 310 had neurological disease, 101 had carditis, 79 had arthropathies, and 9 had EM; for 35 patients, a diagnosis of Lyme disease was confirmed. Of these 35, 68% had neurological disease, 6% had carditis, and 26% had EM. Twelve probable cases of Lyme disease were noted. The male-to-female ratio of patients with confirmed or probable disease was 1.6; all age groups were represented, but 25% of patients were within the age group of 0-9 years. The number of cases of Lyme disease decreases from the north of Spain (41%) to the south (26%), a distribution that is in agreement with the known range of Ixodes ricinus. Borrelia burgdorferi is a frequent cause of infection in some areas of Spain. It is possible that relapsing fever accounts for some of the serological reactivity to B. burgdorferi in residents of the south of Spain.

Adolescent↗
PubMed1993

Molecular characterization of the lethal of scute genetic function.

The lethal of scute (l'sc) genetic function, which plays an essential role in the early development of the central nervous system of the Drosophila embryo, is localized within the achaete-scute complex (AS-C). Several lines of evidence have suggested that the AS-C T3 transcription unit corresponds to the l'sc function. We demonstrate that short fragments of DNA, containing the T3 transcribed region and a few kilobases of flanking sequences, rescue, albeit partially, the lethality and neural phenotype of l'sc deletions. Still, the complex wild-type pattern of expression of T3 is not reproduced by the transduced genes. This depends on cis-control elements scattered within the entire AS-C DNA and intermingled with regulatory elements specific for other AS-C transcription units. These elements are necessary for the initial activation of T3 in the neuroectoderm, probably mediated by axis-patterning genes. The presence of a cluster of E-boxes, upstream of the T3 transcribed region, suggests another level of control of T3 expression by basic-helix-loop-helix proteins, among them its own gene product.

Amino Acid Sequence↗
PubMed1992

Generation of murine triomas secreting bi-specific monoclonal antibodies that recognize HBsAG ad and ay subtypes.

We report the generation of murine triomas by fusing splenocytes from mice previously immunized with HBsAg ay-subtype and a hybridoma, secreting anti-HBsAg ad-subtype monoclonal antibody, which was rendered HGPRT- by induced mutagenesis with N-methyl-N'nitro-N-nitrosoguanidine. The fusion yielded a 83.8% of hybrids showing the antigen specificity of the parental hybridoma and a 16.1% of bi-specific monoclonal antibodies. One of them, coded as 1C8A5, showing a heavy chain isotype (IgG1/IgG2b) was used as capture reagent in an ultramicro-ELISA. As little as 0.78 I.U. of both HBsAg ad- and ay-subtypes could be realiably detected.

Animals↗
PubMed1992

[Production and characterization of monoclonal antibodies directed against the hepatitis B surface antigen].

Hepatitis B virus surface antigen (HBsAg) found in a commercial vaccine was use as immunogen and antigen for the production and selection of murine monoclonal antibodies against this viral antigen. Antibody relative avidity was determined based on their capture capacity. Competition studies, and the differential recognition pattern of vaccine preparations showed that high avidity IgG1 antibodies were directed against two distinct antigenic regions. Among them, 6F4 was most suitable for the detection of HBsAg in a sandwich ELISA system, using an IgM antibody, 5E8, as capture. However, the combined use of 6F4 with another which does not recognize the same epitope did not improve the sensitivity of the assay. On the other hand, the combination of 6F4 with a lower avidity IgG1 antibody, 6G10, increased the universe of antigenic diversities recognized by this system. An enzyme immunoassay for detection of HBsAg is proposed, using 3 monoclonal antibodies: one IgM as capture and two IgG1 for detection.

Animals↗
PubMed1991

2,3,5-Triphenyl tetrazolium chloride (TTC) reduction as exponential growth phase marker for mammalian cells in culture and for myeloma hybridization experiments.

Triphenyl tetrazolium chloride in vitro reduction by cells produces a red formazan pellet which can be extracted and measured. We have shown that such reduction is associated with animal cell growth, and particularly with the specific growth rate, so the measurement of Triphenyl tetrazolium chloride reduction is proposed as a physiological marker of the exponential growth of cultured cells. Further application of this technique is shown using this Redox reaction for estimating plasmacytoma fusion potential for hybridoma cell line production.

Animals↗
PubMed1990

Competence to develop sensory organs is temporally and spatially regulated in Drosophila epidermal primordia.

The Drosophila adult cuticle displays a stereotyped pattern of sensory organs (SOs). Its deployment requires the expression of the achaete (ac) and scute (sc) genes. Their products confer to cells of epidermal primordia (imaginal discs and histoblasts) the ability to become SO precursors (SOPs). In imaginal discs, ac and sc expression is spatially restricted to cell clusters within which one or a few cells become SOP(s). With the help of ubiquitous sc expression provided at different developmental times by a heat shock-sc (HSSC) chimeric gene, we have analyzed the response of epidermal primordia to the proneural action of the sc product, and have tested whether the patterned distribution of ac/sc products is necessary to position SOs correctly within the epidermis. Each primordium responds to HSSC expression by developing SOs only during a characteristic developmental period. In the absence of the endogenous ac and sc genes, most SOs induced by HSSC are of the correct type and are located in wild type positions. These results indicate that the capacity of primordia to respond to sc is temporally and spatially regulated, that specification of the type of SO does not depend on ac/sc, and that SO positioning utilizes topological information independent of the spatially restricted distribution of ac/sc products.

Abdomen↗
PubMed1990

Evaluation of biological sample mineralisation methods for the determination of fluorine by graphite furnace molecular absorption spectrometry.

Various mineralisation methods were evaluated as means of treating different liquid and solid biological samples for the determination of fluorine by the formation of aluminium monofluoride in an electrothermal graphite furnace and molecular absorption spectrometry (AIF-MAS). Simple sample dilution and the use of 0.01 M Al3+ + 0.01 M Sr2+ solution as a matrix modifier are sufficient to determine the fluorine content in most liquid samples, although some require the addition of 0.3 M ammonium nitrate to the matrix modifier solution in order to diminish background absorbance. In solid samples, treatment methods routinely used with fluoride ion-selective electrodes such as microdiffusion, furnace ashing - microdiffusion and oxygen flask combustion, were tested for compatibility with AIF-MAS. The results were compared with those obtained with a fluoride ion-selective electrode. The proposed mineralisation methods were checked for applicability to different plants, foodstuffs and other biological materials. Some of the methods gave an over-all precision of better than 10%, which is often acceptable, and all methods gave recoveries above 80%. Differences between labile + ionic fluoride and total fluorine can be established by sample treatment.

Evaluation Studies as Topic↗
PubMed1983

Prevalence of oral leukoplakia in Havana City, Cuba.

A survey related to the detection of precancerous lesions of the oral cavity has been done in Cuba for the first time. The sample comprised 749 randomly selected workers from Havana City Province, taking into account the census records of the Cuban population up to 1979. Prevalence of lesions and their relation to age, sex and predisposing factors, such as smoking, alcohol habits and mechanical trauma were studied. 4.4% of leukoplakia and preleukoplakia considered together and 2.1% leukoplakia alone, and two cases of oral lichen planus and leukokeratosis nicotina palati (0.1% of each) were found. The former lesions were more frequently encountered in people above 50 years old, specially in males and specifically among those who had smoked for more than 10 years. Sites of location most frequently encountered were the buccal mucosa and the labial commissures.

Adult↗
PubMed1982

[A dynamic study of HGH, zinc and copper in diabetic girls. Preliminary report].

A dynamic study study on secretion of HGH in diabetic girls under the combined stimulus of L-dopa and L-arginina is performed. Serum levels for Zinc and copper are measured. Results show that as HGH increase, copper levels decrease. Correlation (r = 0.81, p = 0.05) points to an inverse dependence of both parameters. Concomitantly, the values obtained for zinc and copper are correlated (r = 0.82, p = 0.03). During stimulation, all patients showed an increase in glycemia and a significant correlation between both parameters was found (r = 0.76, p = 0.05).

Adolescent↗
PubMed1980

[Absence of hypoplasia of fingernails and toenails and terminal phalanges of hands and feet (author's transl)].

A case study of a female patient in which most of the fingernails and toenails and terminal phalanges of hands and feed were absent, together with retarded psychomotor development, minor mental retardation and seizures due to simple cerebral cyst, with bilateral deafness is presented. This association, similar to Coffin-Siris syndrome, is not found in the literature.

Abnormalities, Multiple↗