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J Serrano

Publications and source records attributed to J Serrano.

At least 163 records · Page 9Linked to original sources
PubMed1990

The insulin-like growth factor I (IGF-I) gene is expressed in chick embryos during early organogenesis.

A definition of the role of IGF-I in differentiation and development requires a detailed understanding of its expression and tissue-specific regulation in embryogenesis. Standard techniques for analysis of IGF-I gene expression are not sufficiently sensitive for studies in early embryos. We have used the highly sensitive polymerase chain reaction (PCR) to study IGF-I gene expression in whole chick embryos from the late blastula stage (E0 = laying) through the end of organogenesis (day 8), and in liver, brain and pancreas during mid-late embryogenesis and perinatally (hatching = day 21). Although at low levels in the blastoderm and gastrula, IGF-I mRNA was detectable in the whole embryo in all stages studied, with a tendency of the signal to increase with age during the first week of embryogenesis. In mid- and late embryogenesis, we easily detected IGF-I mRNA transcripts in pancreas and brain while the levels in the liver were barely detectable. Liver IGF-I mRNA increased markedly at the peak of postnatal growth (day 50). These studies suggest that while the major source of postnatal IGF-I may be the liver, extrahepatic tissues may be the predominant source of IGF-I during prenatal chicken development.

Animals↗
PubMed1990

Episodic nyctohemeral secretion of melatonin in adult humans: lack of relation with LH pulsatile pattern.

The concentration of melatonin and LH were determined in plasma samples obtained at 10-min intervals during 4 h of darkness (00.00-04.00 h) from 4 normal women, age 23-27 years, in the early follicular phase of the menstrual cycle and in 6 normal men, age 23-31 years. Additionally, melatonin concentration was determined in samples obtained from the men at 10-min intervals for 4 h during the day (10.00-14.00 h). A pulsatile pattern of melatonin secretion was found for all the subjects during darkness. There was no significant difference between women and men as to the number of pulses (2.8 +/- 0.5 vs 5.2 +/- 1.0 per h), amplitude of pulses (51.3 +/- 28 vs 27.2 +/- 6 ng/l), concentration per 4 h (32.5 +/- 13 vs 31.0 +/- 5 ng/l), or apparent half-life of melatonin (19.3 +/- 2.3 vs 15.3 +/- 7.5 min). The mean amplitude of the melatonin pulse correlated (r = 0.863, p less than 0.001) with the mean melatonin concentration per 4 h. A pulsatile LH secretion pattern was found for the 10 subjects and did not correlate significantly with the melatonin secretion pattern. The results are consistent with an independent signal for the demonstrated nyctohemeral pulsatile melatonin and LH secretions.

Adult↗
PubMed1990

[Cold auto- and alloantibodies considered "benign"--do they have some pathological significance?].

In our Blood Bank the screening for irregular antibodies is performed on blood bags and patient's serum and is done at 37 degrees C as well as 22 degrees C even when we are conscious that the test at 22 degrees C is devoid of any practical value as far as transfusional haemolytic reactions are concerned. A total of 23,021 patients and 91,021 blood bags have been studied in the last 10 years. The results have been analyzed in order to find out any possible association of cold autoanti-I antibodies, or cold alloantibodies, mainly anti-P1, anti-Leb, anti-Lea and anti-Lex, with certain diseases. The cold antibodies looked for in the present study are neither "natural" antibodies reactive only at 4-10 degrees C, since they were not investigated at such low temperatures, nor pathological antibodies, reactive up to 37 degrees C and/or endowed with haemolytic activity. They are instead antibodies, reactive at 22 degrees C, that interfere with compatibility tests and with screening for irregular antibodies, when the assay is performed at room temperature. In our experience, by far the most prominent antibody in this category is auto-anti-I, amounting to over two thirds of the positive findings. This autoantibodies, as well as allo-anti-P1, appear much more frequently in patients that in donors, whereas significant differences are not found with anti-Lewis antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies↗
PubMed1990

[Magnetic resonance imaging of low intensity field in the follow-up of pneumonectomized patients].

The authors investigated the real contribution of low-field MR imaging in the follow-up of pneumonectomized patients. Literature on the subject is surprisingly poor, even though MR diagnostic capabilities seem to be great in these patients. Because of the peculiar anatomical features of pneumonectomized patients, low-field MR imaging yields high-quality images. The operated hemithorax, with the postpneumonectomy space full of fluid, in the absence of respiratory movements is free of movement artifacts. The latter are known to worsen image quality in thoracic MR imaging, especially without respiratory gating. In the study of mediastinum and operated hemithorax MR imaging provides the highest diagnostic contribution. In the mediastinum MR images demonstrate enlarged lymph nodes and tumor recurrences and is superior to CT especially when great vessels are involved. In the study of the operated hemithorax, MR imaging is preferable to CT to identify parietal lesions, because of its higher spatial resolution. Moreover, MR imaging allows tumor recurrences to be differentiated from normal muscular tissue and from fibrous tissue on the basis of their different signal intensities as observed on the various pulse sequences.

Female↗
PubMed1990

[Incidence and characterization of erythrocyte antibodies in a hospital blood bank. Study over a period of 9 years (1980-1988)].

Serological studies done in 21,124 patients receiving blood transfusions and in 85,202 units of blood, during a period of 9 years in a 750-bed University Hospital, are presented. 311 out of 21,124 blood transfusion recipients developed warm type alloantibodies, equivalent to an 1.4% incidence. 178 out of 85,202 blood units were found positive for the same kind of antibodies, thus giving a frequency of 0.2%. The most common warm alloantibodies were: anti-Rho (D) alone or in combination, 54%; anti-K 20%, anti-rh" (E) 14% and anti-Fya 5.3%. Warm alloantibodies occurred more frequently in patients that in donors, and more in women that in men, as already reported from other laboratories. Cold alloantibodies were detected in 0.83% of transfused patients and 0.19% of blood units. Their specificities were: anti-P1 44%, anti-Leb 16.2%, anti-Lea 5.9% and anti-M 3.5%. Cold alloantibodies appeared with the same frequency in patients as in donors, and more often in women that in men. 38.5% of all the antibodies found were autoanti-I or cold non-specific; they occurred much more frequently in patients, without any significant difference between both sexes.

Agglutinins↗
PubMed1989

Insulin-like growth factor I and insulin regulate delta-crystallin gene expression in developing lens.

Normal development of the chicken embryo requires insulin and insulin receptors. Insulin and also insulin-like growth factor I (IGF-I) can stimulate embryonic growth when applied in vivo at the beginning of organogenesis (Girbau, M., Gomez, J. A., Lesniak, M. A., and De Pablo, F. (1987) Endocrinology 121, 1477-1482). In the present work we chose the developing eye lens, an avascular organ composed of a single cell type, to characterize further the specific effects of insulin and IGF-I upon cell differentiation and gene expression. Epithelial cells (before terminal differentiation) and fiber cells (terminally differentiated) were cultured in the presence of the hormones. delta-Crystallin mRNA steady-state levels as well as nuclear delta-crystallin gene transcription were measured. Either insulin or IGF-I (0.1-10 ng/ml) increased (2-4-fold) delta-crystallin mRNA in epithelial and fiber lens cells from day 6 embryos. The effect of insulin was largely blocked by the Fab fragment of anti-insulin receptor antibody (B-10). By contrast, as it had been shown for metabolic actions in other systems, bivalent B-10 IgG itself mimicked insulin action, i.e. it induced an increase on delta-crystallin mRNA levels. Thus, insulin appears to act through its own receptor in regulating the levels of delta-crystallin mRNA. There was a differential transcriptional component in insulin and IGF-I effects on delta-crystallin gene expression. IGF-I induction of transcription, as measured by nuclear run-on assay, is greater than insulin induction (approximately 2.5-fold versus 1.4-fold) and faster. The delta-crystallin gene will provide the opportunity to analyze the action of insulin and IGF-I on the expression of a structural protein marker of cell differentiation during early embryonic development.

Animals↗
PubMed1989

Insulin gene expression in chicken ontogeny: pancreatic, extrapancreatic, and prepancreatic.

Insulin has metabolic, growth, and differentiation effects in chicken embryos in vivo and it is required for normal development. Whether the pancreas is the sole source of insulin in embryogenesis is controversial. In the present study we investigated (1) the developmental pattern of expression of the chicken insulin gene in the pancreas; (2) the expression of the insulin gene in three nonpancreatic tissues, liver, brain, and lower limb, during chicken development; and (3) the expression of the insulin gene at prepancreatic stages and during chicken embryo organogenesis. Hybridization of synthetic species-specific insulin oligonucleotides to pancreatic frozen section in situ and to Northern blots revealed a major increase in insulin messenger RNA (mRNA) levels during the third week of embryonic development. The hybridization histochemistry showed both an increase in the levels of insulin mRNA per pancreatic islet and, in addition, an increase in the number of insulin mRNA containing islets with development. By Northern analysis there was a major polyadenylated transcript of 0.6 kb, which increased in abundance approximately 30-fold during this interval. Under the same stringency conditions used for pancreatic RNA an insulin transcript was detected in liver RNA blots. The abundance of this hepatic insulin mRNA was about 100-fold less than the pancreatic insulin mRNA and, in contrast to the latter, did not increase in late development. Primer extension experiments demonstrated that the insulin transcripts of pancreas and liver had similar 5' ends. No insulin mRNA was detected by Northern analysis or primer extension either in whole brain or lower limb total RNA from several developmental stages. A very low abundance insulin mRNA was detected in whole embryo at Day 8 and body regions at Day 4 and Day 5 when organogenesis of the pancreas takes place. Interestingly, a polyadenylated insulin transcript was detected, as well, in whole Day 2 and Day 3 embryos (stages 10 to 20, with 20 to 40 somites) before differentiation of beta cells occurs. Thus, there is differential developmental regulation of the insulin gene in several chicken embryo tissues and the expression of insulin precedes pancreatic maturation. These findings support the proposed role of insulin in differentiation and development in vivo and suggest a paracrine type of action of the hormone in early embryos before blood circulation begins.

Animals↗
PubMed1989

[Corynebacterium D2-induced encrusted cystitis].

Two cases of patients with cystitis cystica secondary to urine infection, caused by resistant corynebacterium D2, are presented. The clinical features were important dysuria and frequency, alkaline urine Ph (Ph 8 and 9). The urine cultures were obtained with the standard techniques, after 72 hours of incubation. They were treated with vancomycin, ciprofloxacin and hydroxinamic acid with good response.

Aged↗
PubMed1989

Inquiry between European thoracic surgeons and chest physicians about the mandatory examinations before operating a lung cancer.

The purpose of this inquiry is to try to attain a common opinion between European Thoracic Surgeons and Chest Physicians about the examinations which are mandatory or not mandatory but useful before to put the indication to lung cancer resection. The examinations proposed are divided from functional point of view and from oncological as well as technical point of view. A questionnaire specially conceived was sent to 78 Thoracic Surgeons and Chest Physicians in Europe. Answers obtained by 52 institutions are analysed.

Cost-Benefit Analysis↗
PubMed1988

Separation and o-phthaldehyde fluorometric determination of 5-hydroxy- and 5-methoxyindoleamines by thin-layer chromatography: selected applications.

Individual 5-hydroxyindoles and 5-methoxyindoles were simultaneously isolated and quantified, after o-phthaldehyde condensation in different concentrations of HCl, followed by separation on silica gel plates. The 5-hydroxyindoleamines and 5-methoxyindoleamines were differentiated by intense orange and blue fluorescences, respectively. Distinct Rf values with new phase composition and optimal HCl concentrations in the condensation reaction were established for each of the nine indoleamines tested. Minimal detectable doses ranged from 0.2 ng for 5-methoxytryptophol to 4 ng for 5-hydroxyindole acetic acid. The above methodology was applied in order to determine platelet serotonin. Preliminary results suggest that this method could be adapted to other selected biological samples.

Amines↗
PubMed1988

Serum zinc binding capacity in pregnant women.

Zinc is an important element during the prenatal period. Since plasma zinc levels are not directly related to the nutritional status of this metal in pregnant women, we designed this study to find out if plasma protein zinc binding capacity is a more reliable parameter than total serum zinc to establish zinc nutritional status during pregnancy. We analyzed total serum zinc and zinc binding capacity in 84 normal pregnant women and in 14 nonpregnant women. Within pregnant women, samples were classified according to the gestational age. Total zinc serum was significantly decreased in pregnant women as compared to control ones. The decrease in zinc occurred slowly during the whole period of pregnancy; a negative correlation was found between serum zinc and gestational time. Protein zinc binding capacity was found to be significantly higher in pregnant women than in the control ones. This parameter was positively correlated to total serum zinc in pregnancy. We conclude that since the protein zinc binding capacity increases with advancing gestation, pregnant women take advantage of this to maintain the levels of serum-free zinc, transferable to the fetus.

Blood Proteins↗
PubMed1988

Developmental regulation of insulin and type I insulin-like growth factor receptors and absence of type II receptors in chicken embryo tissues.

Chicken embryos are a suitable model for studying the role of insulin, insulin-like growth factors I and II (IGF-I and IGF-II), and their receptors in embryogenesis. We show that plasma membranes from heart, liver, and limb buds, as reported earlier for brain, each have a distinct developmental profile for insulin receptors and type I IGF receptors. In heart and limb buds, IGF binding is higher than insulin binding, but in liver, insulin receptors dominate. Expression of these receptors is, therefore, developmentally regulated and tissue specific. The wide distribution of high-affinity receptors capable of mediating insulin and IGF actions in early organogenesis further supports the possible importance of this family of peptides for differentiation and growth in vertebrates. In all chicken embryo tissues studied, both IGF-I and IGF-II appeared to bind to a type I IGF receptor. We have not detected a receptor with the peptide binding and structural characteristics of the mammalian type II IGF receptor. The type II receptor was absent in embryos, liver from newly hatched chicks, and adipocytes from older chicks, which suggests that the chicken may lack this subtype of IGF receptor.

Animals↗
PubMed1987

Mixed enzymic reaction--internal diffusion kinetics of nonuniformly distributed immobilized enzymes. The system agarose-micrococcal endonuclease.

Two types of (CNBr-activated) Agarose-staphylococcal endonuclease derivatives have been prepared, one with the enzyme uniformly distributed in the support, and the other with the enzyme preferentially bound in the most external part of the support particles; the latter were obtained using agarose of very small pores and a high degree of activation. Quantitative enzyme distribution has been determined by scanning fluorescence microscopy. With these insoluble enzyme derivatives, a kinetic study for the hydrolysis of a mononucleotide has been carried out. A simple theoretical model for nonuniformly distributed insoluble enzyme derivatives, which considers only the case of mixed enzymic reaction-internal diffusion kinetics, is proposed. The experimental data agree very well with the predictions of the model.

Cyanogen Bromide↗
PubMed1987

Insulin and IGF receptors are developmentally regulated in the chick embryo eye lens.

We have previously reported that insulin-like growth factor (IGF) receptors appear to predominate over insulin receptors in early stages of embryogenesis in the chick (days 2-3 whole embryo membranes). Overall, [125I]IGF I and II binding to specific receptors was maximal when the rate of brain growth is highest. In the present study we used the embryonic chick lens, a well-defined tissue composed of a single type of cell, to analyse whether changes of insulin and IGF I binding are correlated with changes in growth rate and differentiation state of the cells. We show that both insulin receptors and IGF receptors are present in the lens epithelial cells, and that each type is distinctly regulated throughout development. While there is a direct correlation between IGF-binding capability and growth rate of the cells, there is less relation to differentiation status and embryo age. Insulin receptors, by contrast, appear to be mostly related to the differentiated state of cells, decreasing sharply in fibers, irrespective of their developmental age.

Animals↗
PubMed1987

Circulating immunoreactive somatostatin in gastrointestinal diseases. Decrease after vagotomy and enhancement in active ulcerative colitis, irritable bowel syndrome, and duodenal ulcer.

The main source of circulating immunoreactive somatostatin (IRS) seems to be the gastrointestinal tract. We therefore investigated plasma IRS in patients with various gastrointestinal diseases. Mean basal IRS oscillated between 46 and 73 pg/ml. A postprandial rise was observed in all patients and age-matched controls. However, the increment was significantly higher in patients with duodenal ulcer (159 +/- 20 pg/ml), active ulcerative colitis (176 +/- 17 pg/ml), and irritable bowel syndrome (194.4 +/- 20.4 pg/ml). Patients with duodenal ulcers who underwent vagotomy showed a decreased postprandial increment (107 +/- 10 pg/ml) when compared with active duodenal ulcer patients. No difference was demonstrable between controls and individuals with gastric ulcer, and patients with inactive ulcerative colitis. These results suggest that vagal innervation plays a role in postprandial IRS stimulation, whereas gastric hyperacidity, acute lesions of the colonic mucosa, and hypermotility of the gastrointestinal tract are associated with an exaggerated postprandial IRS response. Since somatostatin is known to influence many gastrointestinal functions, these variations in circulating IRS concentrations may be of pathophysiologic importance.

Adult↗