Search PubMed⌕ Search

Biomedical subjects

M Morell

Publications and source records attributed to M Morell.

At least 37 records · Page 2Linked to original sources
PubMed1998

Thyroid function in acute pancreatitis.

OBJECTIVES: To analyze changes in the thyroid function in patients with acute pancreatitis. METHODS: Admission serum levels of triiodothyronine (T3), reverse triiodothyronine (rT3), thyroxine (T4) and thyrotropin (TSH) were determined in 20 patients with pancreatitis and 20 healthy control patients. Another group of 20 patients with upper digestive haemorrhage was included to study possible changes in the pattern of thyroid function in hemodynamic alterations. In addition, laboratory indicators of liver, renal and pancreatic functions were measured in all groups. RESULTS: Our results demonstrated low levels of T3 in 20% of patients with pancreatitis and increased rT3 levels in 75% of them. Thyrotropin was always among reference ranges and only one case presented a low level of T4. No significant alterations were detected in patients with upper digestive haemorrhage. CONCLUSIONS: These results suggest that pancreatitis may play a role in the genesis of these changes, since other factors such as diet and cellular hepatic alteration appear to have had no effect on the levels of thyroid hormones in these patients. In other studies those changes in the thyroid function can be relationed with the prognosis in acute pancreatitis.

Acute Disease↗
PubMed1997

Absence of linkage between type III protein S deficiency and the PROS1 and C4BP genes in families carrying the protein S Heerlen allele.

To elucidate the molecular basis of hereditary protein S (PS) deficiency and, in particular, type III or free PS deficiency, the allelic distribution and segregation patterns of the PS gene (PROS1) polymorphisms P626A/G and S460P (PS Heerlen) have been analyzed in a group of 45 proposita suffering from type I or type III PS deficiency. No differences between patients and controls were found in the frequency of the P626A/G alleles. By contrast, the frequency of the PS Heerlen allele in the group of patients with type III PS deficiency (9 of 46 chromosomes, P = .196) was significantly higher (P < .001) than in the control group (1 of 300 chromosomes, P = .003). The A allele of P626A/G was always associated with the P allele of S460P. However, this haplotype did not co-segregate with the type III PS-deficient phenotype in 3 of the families. Furthermore, multipoint linkage analysis excluded the whole PROS1 gene in 1 of these families, which is in agreement with the absence of mutations in the PROS1 gene, as determined by sequence analysis. Finally, linkage analysis with 4 microsatellite markers linked to the C4BPB and C4BPA loci also excluded these two genes. From these results we conclude that, at least in some families, the molecular basis of type III PS deficiency is not due to the Mendelian inheritance of a single defect in the PROS1 or in the C4BP genes.

Adult↗
PubMed1997

The effects of the degree of surgical trauma and glucose load on concentration of thyrotropin, growth hormone and prolactin under enflurane anaesthesia.

Sixty patients undergoing gynecological surgery under enflurane nitrous-oxide anesthesia were studied. The goal was to investigate the effects of the degree of surgical trauma and glucose load on the pattern of TSH, GH and PRL secretion before, during and following surgery. For this purpose the patients were divided into four groups according to the severity of the operation and the type of fluid administered. The groups were as follows: group 1, major surgery--glucose solution; group II, major surgery--lactated Ringer solution; group III, minor surgery--glucose solution; group IV, minor surgery--no intravenous fluids. The three hormone concentrations, 45 min after the start of anesthesia, increased in all groups. The highest values for GH and PRL concentration were observed in group IV. This increase was followed by a decrease 24 h and 5 days after induction, at the end of the study, except in group IV where TSH and GH levels fell back to normal values more slowly. These results lead to the following conclusions: a) Enflurane does not suppress hormonal stress response to surgical trauma; b) A similar pattern is obtained for pituitary response, indicating that a general pituitary stimulus takes place in these situations; c) Glucose load plays an important role in pituitary hormonal response to surgical stress; d) There is no direct relationship between the degree of surgical trauma and the hormone levels in patients under enflurane anaesthesia.

Adult↗
PubMed1997

A complex arrangement of genes at a starch branching enzyme I locus in the D-genome donor of wheat.

Genomic DNA fragments from Triticum tauschii (D-genome donor to wheat) carrying starch branching enzyme I (SBE I) type genes have been characterized. One fragment contains one complete gene and two partial genes in 16 kb of DNA. One of the partial genes is oriented in the opposite strand to the other two. The gene that is complete was sequenced. Its structure corresponds closely to that of rice in that exons 3-8 are retained at similar sizes and spacings. A cDNA closely corresponding to the complete gene was isolated and characterized; it codes for a putative protein that represents a novel type of SBE I, as it is shorter at the 3' end than the forms reported so far in other plants. A second genomic fragment contains a different SBE I gene. There appear to be approximately 10 copies of SBE I type genes in wheat (approximately 5 in T. tauschii) and most of them have been assigned to group 7 chromosomes. In situ hybridization indicates that a major locus for the genes is located at the distal end of the short arm of chromosome 7D.

1,4-alpha-Glucan Branching Enzyme↗
PubMed1997

Class I major histocompatibility complex antigens and tumor ploidy in breast and bronchogenic carcinomas.

We determined the frequency of expression of the major histocompatibility complex antigens HLA-A,B,C in tumor cells from 207 primary tumor lesions of breast and bronchogenic carcinomas, to see if the expression of theses antigens was linked with several clinicopathological parameters associated with tumor aggressivity, such as abnormal cellular DNA content. We compared tumor tissues with nonneoplastic tissues and tissues from 15 benign breast lesions. HLA class I expressor and nonexpressor tumor cells were determined by using immunohistochemical stains (PAP and APAAP methods) and antibodies against these antigens. Reduction of HLA class I antigen was detected in 65 tumors (31.7%) and was significantly associated with poor tumor differentiation and abnormal cellular DNA content (p < 0.001). These characteristics might define a group of aggressive tumors in which the decrease of HLA class I antigens would enable tumor cells to avoid eliciting host immune responses. On the other hand, the altered regulatory mechanisms, of tumors with abnormal cellular DNA content, might modulate the expression of HLA class I molecules.

Breast Neoplasms↗
PubMed1997

PSA excess in the differential diagnosis of prostate carcinoma.

OBJECTIVE: To evaluate the efficiency of PSA excess in distinguishing prostate cancer (PC) in its early stages from benign prostatic hypertrophy (BPH) and compare it with the efficiency of serum PSA. METHODS: A cross-sectional study was carried out on 27 patients with PC and 46 with BPH, whose serum PSA and prostatic volume were determined. PSA excess was calculated as the difference between serum PSA and predicted PSA according to the gland volume, calculating the latter as the prostatic volume multiplied by factor 0.3 ng/ml/g. RESULTS: PSA excess values were significantly higher in patients with PC, while serum PSA levels were not different between the two populations studied. Receiver operating curves (ROC plots) showed a higher diagnostic utility for PSA excess, with a maximum efficiency of 73% at a cut-off point of -13 ng/ml. The predictive value of a positive result is slightly higher for serum PSA, but PSA excess showed a predictive value of a negative result superior to that of PSA.

Adenocarcinoma↗
PubMed1997

Lack of correlation between codon 12 K-ras mutations and major histocompatibility complex antigens in bronchogenic carcinomas.

In experimental systems, an association between K-ras activity and expression of major histocompatibility complex (MHC) molecules has been reported. In this study, 52 surgically resected bronchogenic carcinomas were studied for human leukocyte antigen (HLA) class I and II expression, and for the presence of point mutations in codon 12 of the K-ras gene. HLA class I loss was detected in 18 carcinomas, and most of the tumors (43 cases) were found negative for HLA class II antigen expression by the APAAP technique with specific monoclonal antibodies. Analysis using the polymerase chain reaction (PCR), together with selective hybridization using mutation-specific synthetic oligonucleotides, demonstrated K-ras mutations in five cases, all of them corresponding to the adenocarcinoma subtype (31.2% of the adenocarcinomas included in our study) with a poor degree of differentiation. We did not find any correlation between K-ras mutations and HLA class I and II expression in bronchogenic carcinomas. Therefore, it would appear that downregulation of MHC antigens by point mutations of K-ras does not take place in vivo.

Carcinoma, Bronchogenic↗
PubMed1997

Quantification by additive RT-PCR of HIV-1 RNA plasma levels in different stages of HIV-1 infection.

In this study, virion-associated RNA was measured in plasma from twenty six patients in various stages of HIV-1 disease by the additive RT-PCR method. Plasma viral RNA levels were inversely correlated (r = -0.72894) with total CD4+ cell counts and directly (r = 0.86964) with serum titre beta 2-microglobulin in chronically infected patients. This additive RT-PCR is based on a mathematical logistic adjustment of the standard curve and the use of an internal standard identical to the target molecule, which represents a control system for the efficiency of RT-PCR and allows a continuous assessment of the accuracy based on the recovery.

Acquired Immunodeficiency Syndrome↗
PubMed1997

[A new type of headache of ocular origin: ophthalmotonic headache. Diagnosis and treatment].

INTRODUCTION: In some patients it was seen that chronic headaches disappeared after laser iridectomies had been done to prevent glaucoma, in persons with normal intra-ocular pressure (IOP). OBJECTIVE: To make a study of patients with headache, some of whom were treated with topical beta-blockers (carteolol) and others by Yag-laser iridectomies. The effect on headache and IOP was analyzed. MATERIAL AND METHODS: A survey, ophthalmological examination and headache provocation test were carried out in patients with headaches, and the changes in IOP determined by pharmacologically inducing miosis and mydriasis were recorded. Three treatment groups were formed and the results analyzed statistically. RESULTS: In the 12 patients treated pharmacologically, 62% improved and in 14% the headaches disappeared. In the 16 treated using laser 94% were cured and 6% improved. When both types of treatment were used on 9 patients, 22% improved and 78% were cured. The validity of the ocular pressure curve was checked in the diagnosis of blockage of the pupil. CONCLUSIONS: Some headaches of ocular origin (ophthalmotonic), not previously described, occur due to abrupt changes in intraocular pressure, and improve significantly when the IOP is reduced by beta-blockers or Yag-laser iridectomies are done. A valid provocation tests for diagnosis of this type of headache is described. We consider that blockage of the pupil and/or of the angle of the anterior chamber are possible etiopathogenic mechanisms.

Adrenergic beta-Antagonists↗
PubMed1996

Homozygosity for R87H missense mutation and for a rare intron 7 DNA variant (7054G --> A) in the PROC genes of three siblings initially classified as heterozygotes for protein C deficiency.

We report the results of protein C gene (PROC) analysis in a Spanish family with hereditary PC deficiency characterized by the presence of three siblings with PC anticoagulant activity levels clearly below 50% of normal and PC antigen and amidolytic activities between 50 and 75% of normal. Their parents are first cousins and have PC levels between 50 and 80% of normal. Sequence analysis of the whole coding sequence of the PROC gene revealed that the three siblings are double homozygotes for a G to A transition at nucleotide 3203 that replaces arginine 87 by histidine (R87H) and for another G to A transition at nucleotide 7054, in intron 7 (7054G --> A). Both parents and one sister were found to be double heterozygotes for these two mutations. Screening for the intronic mutation in a control group and RT-PCR cDNA studies from ectopically transcribed mRNA indicated that 7054G --> A is most likely a rare but neutral DNA variant. These results and the fact that heterozygosity for the missense R87H mutation has also been found associated with a slightly decreased PC anticoagulant activity in another Spanish family, lead us to conclude that homozygosity for R87H is responsible for the PC deficient phenotype in these three siblings.

Adenine↗
PubMed1996

Aberrant RNA splicing of the protein C and protein S genes in healthy individuals.

RNA-based studies are an important tool for the identification and functional characterization of mutations underlying inherited disease. These studies could in principle be compromised by 'aberrant splicing' (the generation of alternatively spliced transcripts lacking any obvious function) during normal expression of the genes under investigation. Using a highly sensitive RT-PCR assay, we show here that aberrant splicing is a frequent occurrence during expression of the protein C (PROC) and protein S (PROS) genes. Aberrantly spliced transcripts were present in different cell types including liver, the main expressing tissue for both protein C and protein S. In an attempt to compare individual mRNA splicing patterns, PROC and PROS RNA from easily accessible cells of different healthy control individuals was studied. However, variation between different RT-PCR assays from the same individual precluded both the relative quantitation of the aberrant transcripts and the analysis of interindividual differences. Our findings are consistent with the notion that a low level of aberrantly spliced transcripts are routinely generated during PROC and PROS gene expression. The possibility that these transcripts may complicate the RT-PCR analysis of pathological transcripts must be taken into account when RNA-based strategies of disease analysis are considered.

Electrophoresis, Agar Gel↗
PubMed1995

A novel polymorphism (6376 G/T) in intron 7 of the human protein C gene.

A novel polymorphism (6376 G/T) in intron 7 (17) of the human PROC gene has been identified by direct DNA sequencing. Restriction analysis with the use of mutagenic primers indicate that the allele frequencies are 0.17 (allele T) and 0.83 (allele G), with a calculated heterozygosity of 28%.

Base Sequence↗
PubMed1995

Severe type I protein C deficiency in a compound heterozygote for Y124C and Q132X mutations in exon 6 of the PROC gene.

We report the genetic abnormalities in the protein C genes of a Spanish child with neonatal purpura fulminans and disseminated intravascular coagulation, associated with undetectable protein C levels. Direct sequencing of the nine protein C gene exons and their splice junctions indicated that the proband is a compound heterozygote with two mutant protein C gene alleles, Y124C and Q132X, that do not express protein C in plasma. The Y124C mutation was inherited from the mother and is due to a novel A to G transition at nucleotide 3416, which results in the substitution of cysteine for tyrosine 124, a highly conserved amino acid in EGF-like domains. The paternal inherited mutation (Q132X) is a C to T transition at nucleotide 3439, which replaces glutamine 132 with a Stop codon signal. This mutation, if expressed, should result in the synthesis of a truncated protein of 131 amino acids. Y124C or Q132X are present in the heterozygous state in the asymptomatic parents and siblings of the proband, all of which have half the normal plasma levels of protein C. Q123X has also been identified in families where type I PC deficiency is inherited as a clinically dominant trait. Therefore, the presence of the same mutation in a family showing a clinically recessive pattern of inheritance indicates that other factors, apart from the type of protein C gene mutation, are responsible for the clinical expression of protein C deficiency.

Alleles↗
PubMed1994

A sensitive enzyme immunoassay for angiotensin II in serum.

A sensitive and specific enzyme immunoassay for measuring angiotensin II (AII) has been developed as a convenient alternative to a radioimmunoassay. An antiserum to AII was prepared using AII conjugated by carbodi-imide to rabbit serum albumin, and coated on to microwell plates. The labelled antigen was prepared from AII and horseradish peroxidase using the periodate method. This enzyme immunoassay was a simple two-step procedure: 0.1 ml of AII-extracted plasma was incubated for 1 h at 37 degrees C; and 1 ml of labeled AII was incubated for 1 h at 37 degrees C. Bound horseradish peroxidase activity was then determined using o-phenylenediamine as chromogen by measuring the absorbance at 492 nm. The lower detection limit of the assay was 3.5 pmol l-1. Between- and within-assay RSD values were 8.8-18.3% and 6.9-17%, respectively, for concentrations of 10-40 pmol l-1. The accuracy of the assay, determined by recovery and linearity experiments, was 89-106% for recovery and 91-126% for parallelism. The results obtained by the present ELISA method were well correlated with those obtained by an established radioimmunoassay (n = 10, r = 0.96, intercept = 0.9 and slope = 1.02). This assay is easy to perform, rapid and does not require radioisotopes; thus it could be widely applied in clinical laboratories.

Angiotensin II↗
PubMed1993

5' Deiodinase activity in brain regions of adult rats: modifications in different situations of experimental hypothyroidism.

In the central nervous system, type II 5' deiodinase (5'D-II) is highly regulated, as judged by the dramatic changes in enzyme levels observed after abrupt alterations in thyroid status. In this work, the 5'-DII activity has been studied in different situations of experimental hypothyroidism (propylthiouracil, methimazole, thyroidectomy, and low iodine diet), in various brain regions (pituitary, cerebellum, brain stem, hypothalamus, cortex, and whole brain) in adult rats. Propylthiouracil and methimazole significantly increase the activity in all brain regions. These increases are higher in rats treated with methimazole. Thyroidectomy significantly increases the activity in cortex and pituitary. A low iodine diet significantly increases in all brain regions except in the hypothalamus. The concentration of triiodothyronine (T3) studied in the major brain regions remained unchanged. The results obtained show a compensatory mechanism in pituitary and other brain regions in order to maintain the T3 levels in brain tissue.

Animals↗
PubMed1992

[Comparison of homologous and heterologous standard curves using TR-FIA for the determination of total T4 in the rat].

A homologous standard curve for rat T4 measurement has been compared to heterologous standard curves, by a time resolved fluoroimmunoassay (TR-FIA). Homologous standard curves have been carried out starting from rat serum in the absence of thyroid hormone by using Samuel's technique. The security criteria (sensitivity, inter and intraassay precision, and accuracy), were measured and compared between the homologous and heterologous test. Analysis of variance and slopes between homologous and heterologous standard curves showed homogeneous variances, the differences in the slopes being not significant.

Animals↗