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Biomedical subjects

M Giralt

Publications and source records attributed to M Giralt.

At least 19 recordsLinked to original sources
PubMed1992

Opposing actions of Fos and Jun on transcription of the phosphoenolpyruvate carboxykinase (GTP) gene. Dominant negative regulation by Fos.

Jun homodimers and Fos/Jun heterodimers bind to the gene for phosphoenolpyruvate carboxykinase (GTP) (EC 4.1.1.32) (PEPCK) at three sites within the first 350 base pairs of the promoter. These include CRE-1 (-82 to -90), and P3(II) and P4 (-252 to -258 and -268 to -285, respectively). Over-expression of Jun in HepG2 cells resulted in a 10-15-fold increase in the level of transcription of a chimeric PEPCK (-490 to +73)-CAT gene, while expression of Fos decreased transcription and blocked the induction of transcription from the PEPCK promoter by Jun. The action of Fos and Jun on PEPCK gene transcription involved each of the Fos/Jun-binding sites and was modulated by additional transcriptional regulatory elements within the PEPCK promoter. The ability of Fos to inhibit PEPCK transcription was dependent upon P3(I), a region of the promoter which does not bind Fos/Jun heterodimers, but does bind members of the C/EBP family of transcription factors. Stimulation of PEPCK transcription by 8-Br-cAMP or by overexpression of the catalytic subunit of protein kinase A was inhibited by Fos expression. The inhibitory effects of phorbol esters and protein kinase C on PEPCK gene expression may be mediated through the action of Fos and Jun.

Binding Sites↗
PubMed1992

[Non-Hodgkin's lymphomas. I. Clinico-biological features of 307 cases].

PURPOSE: To assess the clinico-biological features appearing in 307 patients with non-Hodgkin's lymphomas (NHL). PATIENTS AND METHODS: The clinical records of 338 patients diagnosed of NHL between January 1975 and December 1988 were revised in retrospect. All cases with histologic diagnosis of NHL aged over 14 years were included, and classified in accordance with the Working Formulation criteria. The following data were analysed: age, sex, first complaints, time elapsed since onset, histologic type, number of sites involved, bulky disease, anaemia, thrombocytopenia, LDH, stage, type of treatment and initial response, survival, and cause of death. The statistical evaluation was performed by actuarial analysis (Kaplan and Meier) and comparison (log-rank test) of survival. RESULTS: According to the three categories of the malignancies, the NHL were distributed into low-grade (37.8%), intermediate (36.1%) and high-grade (26.9%). The mean age of the series was 56.6 years and the M/F ratio was 1.3. Lymph node enlargement was the commonest finding; 36.4% of the patients had symptoms related with the disease, and 26.7% had bulky disease. Anaemia was present in 37.7% of the cases and thrombocytopenia in 14.3%, with similar distribution among the three grades. High LDH levels were found in 44% of the patients. At diagnosis, 85% of the patients were in advanced stages (III+IV) already. Complete response was attained in 51.1% of the cases, with median survival of 48 months. CONCLUSIONS: The clinico-evolutive data found here are similar to other reports in the literature. In one-half of the patients the cause of the first visit is lymph node enlargement. Complete remission is achieved by one out of two patients, this figure being similar for each of the histologic groups. The Working Formulation is useful in determining the different prognostic groups with respect to survival.

Adolescent↗
PubMed1992

[Non-Hodgkin's lymphomas. II. Analysis of the prognostic factors in a series of 307 patients].

PURPOSE: To analyse different clinico-biologic data in order to assess their prognostic value in non-Hodgkin's lymphoma (NHL) patients. MATERIAL AND METHODS: The series comprises 307 patients with NHL diagnosed and treated between 1975 and 1988. The histopathologic diagnosis was revised in accordance with the working formulation system, three prognostic groups being thus considered: low-grade (LGL), intermediate-grade (IGL) and high-grade (HGL) lymphomas. Age, sex, clinical course prior to diagnosis, presence of B symptoms, histologic type, number of lymph-node areas involved, bulky disease, anaemia, thrombocytopenia, LDH, stage and response to therapy were all evaluated for the study. Survival curves were drawn with the Kaplan-Meier method, and the log-rank test was used for comparison of median survival. Whenever the univariate analysis achieved statistical significance, a multivariate analysis was performed by means of a multiple correlation and regression study in accordance with the Cox's model, in which the variables were expressed in a binary model. RESULTS: The following 8 values were found significant in the univariate study of low-grade lymphomas: age, number of involved areas, bulky disease anaemia, thrombocytopenia, LDH, stage, and initial response to treatment. In intermediate-grade lymphomas, the significant findings were age, number of affected areas, bulky disease, thrombocytopenia, LDH, stage, and initial response. For high-grade lymphomas, number of affected areas, thrombocytopenia, LDH, stage and initial response were found statistically significant. Although no significant differences were found for survival within each of the three grades, such differences were significant between them. In the multivariate analysis, age was significant only in the LGL (p < 0.0001) in IGL, age (p < 0.07) and initial response to therapy (p < 0.0001) achieved significant value, and in HGL, stage (p < 0.02) and initial response to treatment (p < 0.0001) attained significance. CONCLUSIONS: The univariate analysis provides various prognostic factors of statistically significance, as reported in the literature, but these after the multivariate analysis was applied, were reduced to age, stage and initial response to treatment.

Adolescent↗
PubMed1991

Identification of a thyroid hormone response element in the phosphoenolpyruvate carboxykinase (GTP) gene. Evidence for synergistic interaction between thyroid hormone and cAMP cis-regulatory elements.

Transcription of the gene for the cytosolic form of phosphoenolpyruvate carboxykinase (GTP) (EC 4.1.1.32) (PEPCK) in the liver is regulated by many hormones including thyroid hormone (T3). In order to identify the elements in the promoter which are required for transcriptional induction by T3, we cotransfected a T3 receptor expression vector with a PEPCK-CAT reporter gene into HepG2 cells. Using vectors with deletions in the PEPCK promoter, we identified a single T3 response element (TRE) between positions -332 and -308. This element binds [125I]T3-labeled T3 receptor contained in nuclear extracts prepared from rat liver. Furthermore, the P3(I) element (-250 to -234), a previously described cis-sequence involved in mediating the induction of PEPCK gene transcription by cAMP, is also required for the T3 responsiveness of the promoter. In the absence of either the TRE or the P3(I) binding sites, no stimulation of transcription from the PEPCK promoter by T3 was observed, indicating that both elements are required for the T3 transcriptional regulation. Finally, a synergistic induction of PEPCK gene transcription by T3 and cAMP is described. This interaction requires both T3- and cAMP-responsive cis-acting elements.

Base Sequence↗
PubMed1991

Life expectancy of patients with chronic nonleukemic myeloproliferative disorders.

This study determines, within the frame of current therapeutic possibilities, the impact of chronic nonleukemic myeloproliferative disorders on expected survival. The survival data for 1067 patients (454 with polycythemia vera, 247 with essential thrombocythemia, and 366 with idiopathic myelofibrosis) were collected from 38 Spanish institutions. The actuarial survival probability of each group of patients was compared with that of the age-matched and sex-matched control population. The survival of the patients with polycythemia vera and essential thrombocythemia did not differ from that of the control population (P = 0.92 and, 0.22, respectively), whereas the survival of the patients with idiopathic myelofibrosis was strikingly reduced with respect to the control population (P = 0.0000000007). Thus, in terms of survival, current therapeutic procedures may be considered as quite satisfactory in patients with polycythemia vera and essential thrombocythemia. On the other hand, due to poor survival of patients with idiopathic myelofibrosis, new therapeutic approaches for this condition are clearly needed.

Aged↗
PubMed1991

alpha Interferon in the management of essential thrombocythaemia.

Thirteen patients (mean age 60.7 years; female:male ratio 10:3) with essential thrombocythaemia were treated with 3 million units (MU)/day interferon alfa-2b subcutaneously (s.c.) for 12 weeks, with all patients requiring a dose reduction after 4 weeks. The mean pretreatment platelet count was 1,400 x 10(9)/L and megakaryocytes were increased in all cases. Splenomegaly was present in six patients and haemorrhagic phenomena were observed in two. Nine patients (69.2%) had objective responses, including two (15.4%) complete responses (platelets less than 450 x 10(9)/L) which were then maintained with 5 MU interferon twice a week. Acute toxicity consisted of flu-like symptoms in 12 patients. Chronic toxicity (mainly leucopenia) was observed in nine patients. In conclusion, initial therapy and then requiring maintenance therapy at a reduced dose. However, the frequent side effects observed make it advisable to use a low dose of interferon alfa-2b, and to treat only those patients with significant symptoms and signs of thrombocytosis.

Adult↗
PubMed1991

[Analysis of 4 prognostic scoring systems in 197 myelodysplastic syndrome patients].

PURPOSE: To evaluate the prognostic significance of four scoring systems applied with predictive trends to myelodysplastic syndromes (MDS). MATERIAL AND METHODS: This study is comprised of 197 patients with MDS diagnosed in accordance with the FAB criteria and followed-up in our Department between Jan '75 and Dec '89. The following MDS subtypes were found: refractory anaemia (RA), 58 cases; sideroblastic refractory anaemia (SRA), 42 cases; refractory anaemia with excess of blasts (RAEB), 46 cases; RAEB in transformation (RAEB-T), 39 cases; and chronic myelomonocytic leukaemia (CMML), 12 cases. The following scoring systems were applied: Mufti's 1985, Varela's 1985, Sanz's 1989 and our own of 1991. The statistical analysis was performed according to Kaplan-Meier actuarial system and the log-Rank test of actuarial survival. RESULTS: (1) Three groups (A, B and C) can be defined by the Bournemouth system, with median survivals of 57.6, 17 and 7.6 months, respectively. The majority of cases (118) were included in group B. Group A has not reached 25% of actuarial survival probability, whereas groups B and C did at 32 and 10 months, respectively. With regard to the morphologic subtypes, RA and SRA were included in groups A and B, and RAEB, RAEB-T and CMML pertained mostly of group C. Sixty cases (90.9%) evolving into acute leukaemia (AL) corresponded to those last groups. (2) The three groups defined by Varela's system (0-1, 2-5 and 6 or more) have median survival of 85.6, 24 and 14 months, respectively. Like in the former system, group 0-1 has not reached 25% actuarial probability, this appearing at 70 and 20 months, respectively, in groups 2-5 and greater than 6. The distribution of the cytological varieties, RA and SRA amongst the groups is heterogeneous although there are more common within the cases included in groups 0-1. All the cases evolving into AL were included in the groups 2-5 and greater than 6. (3) The 3 groups of the system proposed by Sanz (0-1, 2-3 and 4-5) had median survival of, respectively, 58, 15 and 14 months. Like in the preceding cases, group 0-1 has not reached the 25% actuarial probability, while this figure appears at 28 months for group 2-3 and at 20 months for group 4-5. RA and SRA varieties are included chiefly in group 0-1, while RAEB and RAEB-T appear mostly in groups 2-3 and 4-5. The distribution of the cases and evolving into AL in heterogeneous according to this system, although they predominate in groups 2-3 and 4-5. (4) The prognostic groups are defined by the system proposed by us (namely 0-2, 3-5, 5 greater than or equal to 6) with median survivals of 89.3, 17 and greater than 11 months, respectively. Striking difference was seen when studying the cumulated survivals observed, on each of the three percentages considered, between the groups. The different cytological varieties distributed reasonably with higher incidence of RA and SRA in group I and RAEB, RAEB-T and CMML in group III. This system offers statistical significance when comparing RA with SRA, RAEB with RAEB-T and, obviously. RA+SRA with RAEB+RAEB-T+CMML. The evolution into AL showed also statistical significance with respect to the three groups. CONCLUSIONS: 1. Three prognostic groups regarding the patient's survival could be established in our series with all the scoring systems analyzed, except that of Sanz. 2. Low risk (RA and SRA) and high risk (RAEB, RAEB-T and CMML) cytological varieties can be identified with all the scoring systems; that of Sanz is also capable of discriminating RA from SRA. 3. Some prediction on the possibility of evolution into AL can be attained of with each system. 4. The scoring system proposed by us shows higher discriminating capability on the cytologic varieties as well as higher predictive value on the possibility of evolution into AL. Nevertheless, it must be evaluated in other series in order to reach general acceptance.

Actuarial Analysis↗
PubMed1991

[Monoclonal gammopathies of undetermined significance. Clinical course and biological aspects of 397 cases].

The diagnostic criteria, incidence, clinical characteristics and outcome of 397 patients with monoclonal gammopathies of undetermined significance, all of them diagnosed and followed-up at the Haematology Service of the Miguel Servet Hospital, in Zaragoza, between January 1970 and December 1988, were revised. The patients' mean age was 64.7 years (range: 2-89). The M/F ratio was 236/161. The mean concentration of the M component (MC) was 1.17 g/dL (range: 0.20-3.50), this being under 0.50 in 65 cases. IgG was the most frequent MC (71.26%), followed by IgA (14.34%) and IgM (10.82%). Multiple MC was present in 14 cases (3.58). Light chains were passed in urine by 33 patients (8.31%). No associated pathology was found in 213 patients (53.65%) upon MC discovery, while 65 other (16.31%) were carriers of different blood disorders, chronic lymphoproliferative diseases being the commonest (11.57%). In 30 patients (7.30%) the MC was associated to nonhaematological malignancies, and 29 others had an underlying chronic infection. Chronic liver disease was present in 25 cases, and autoimmune disease in 14. Transient monoclonal gammopathy was seen in a small group of patients (6.54%), most of them suffering from acute infectious illness. With regard to the group of patients without any associated pathology, their median follow-up was 37.8 months (range: 18-228). Of them, the MC kept unchanged in 134 cases (62.91%); 47(22.06%) died from any unrelated cause, and 10 others evolved into malignant monoclonal gammopathy. The median clinical course of these last expanded to 60 months (range: 11-124), with an accumulated actuarial risk of 4.5% at 5 years, 15% at 10 years and 26% at 15 years.

Actuarial Analysis↗
PubMed1991

Effect of morphine administration on rat liver metallothionein and zinc metabolism.

The putative involvement of opioid receptors in rat liver metallothionein (MT) regulation has been studied by means of morphine administration. Rat liver MT levels were significantly increased by morphine (10 mg kg-1). This increase was blocked by the opiate antagonist naloxone (4 mg kg-1), suggesting that the effect of morphine on liver MT could involve opioid receptors. The effect of morphine appears to be mediated, at least in part, by glucocorticoids and catecholamines, inasmuch as the administration of specific receptor blockers, RU 486 (100 mg kg-1) for glucocorticoids and labetalol (5 mg kg-1) for catecholamines, diminished liver MT increase induced by morphine. These results identify a potential mediation mechanism for regulating liver MT levels. The putative role of endogenous opioids on liver MT response to stress was also studied by means of opioid receptor blockers. The effect of stress on liver MT levels was not altered by blockade of opioid receptors with either naloxone (4 mg kg-1) or naltrexone (4 mg kg-1) or diprenorphine (4 and 20 mg kg-1), suggesting that endogenous opioids are not involved in MT response to stress. Zn metabolism was also altered by morphine, as morphine administration increased liver cytosolic Zn and decreased serum Zn levels. In contrast to those found in liver MT, these changes were not naloxone-sensitive. The results obtained with RU 486 and labetalol suggest that the effect of morphine on Zn metabolism was mediated in part by glucocorticoids and catecholamines.

Animals↗
PubMed1990

Ontogeny and perinatal modulation of gene expression in rat brown adipose tissue. Unaltered iodothyronine 5'-deiodinase activity is necessary for the response to environmental temperature at birth.

We have performed a sequential study on the abundance of the mRNA for uncoupling protein (UCP), subunit II of cytochrome-c oxidase (COII) and lipoprotein lipase in brown adipose tissue during the fetal and postnatal periods. Moreover, we have determined whether these parameters can be modulated by ambient temperature in the early hours after birth, and at which point in development this sensitivity first appears. UCP gene expression in the fetal and neonatal period has particular features when compared with overall mitochondriogenesis (COII mRNA expression) or with the expression of lipoprotein lipase mRNA. There is a specific induction of UCP gene expression between days 18 and 19 of pregnancy followed by a specific increase of UCP gene expression in utero and a further increase after birth. The acquisition of the physiological apparatus capable of the response to UCP and lipoprotein lipase gene expression to the environmental temperature is not achieved until the last day of fetal development. This result suggests that mechanisms of beta-adrenergic modulation of gene expression in brown fat are already established at birth. From an experiment on iopanoic acid treatment of pregnant mothers, it was concluded that iodothyronine 5'-deiodinase activity is not necessary for the expression of the mRNAs for UCP, COII and lipoprotein lipase in the fetus whereas it is necessary for the acquisition of temperature sensitivity to these parameters at birth.

Adipose Tissue, Brown↗
PubMed1990

Glutathione-S-transferase activity in human superficial transitional cell carcinoma of the bladder. Comparison with healthy controls.

Glutathione-S-transferase (GST) activity and glutathione (GSH) content have been studied in human urinary bladder (UB) specimens obtained from healthy controls (HC) (n = 8) and from patients with superficial transitional cell carcinoma (TCC) (n = 9), either in TCC and in adjacent normal (ANE) tissues of the same patient. The GST activity was significantly higher in TCC in comparison with ANE (ten fold) and with HC (five fold). This activity was also significantly higher in HC than in ANE (two fold). The Km values obtained in the whole population (1.26 +/- 0.3 X 10(-3) mol/l) suggest that a unique form of isoenzyme is present in the UB epithelium and that it is the same acidic form "rho" described in erythrocytes. The GSH content was significantly higher in TCC than in ANE (2.5 fold) and also that in HC (three fold). A good correlation between GST activity and GSH content was observed in HC but not in TCC or ANE. These results demonstrate the relation between the activity of the GST system and the development of the TCC as well as its role in the cellular resistance to chemotherapy. A possible decrease of the GST activity before the development of the tumor is also discussed.

Aged↗
PubMed1990

Lipoprotein lipase mRNA expression in brown adipose tissue: translational and/or posttranslational events are involved in the modulation of enzyme activity.

Lipoprotein lipase mRNA abundance in rat brown adipose tissue increases during the first 24 h of cold exposure. Lipoprotein lipase mRNA levels do not change in brown fat throughout pregnancy and lactation, whereas enzyme activity is significantly lowered. After 5 h of acute cold or noradrenaline administration there is a 2-fold increase in lipoprotein lipase mRNA abundance, whereas lipoprotein lipase activity is stimulated to more than 6-fold the basal values. It is concluded that translational and/or posttranslational mechanisms are involved in the noradrenergic modulation of lipoprotein lipase activity in brown fat.

Acclimatization↗
PubMed1989

Adaptative decrease in expression of the mRNA for uncoupling protein and subunit II of cytochrome c oxidase in rat brown adipose tissue during pregnancy and lactation.

Uncoupling-protein (UCP) mRNA expression is decreased to 15% of virgin control levels between days 10 and 15 of pregnancy, and remains at these low values during late pregnancy and lactation. Abrupt weaning of mid-lactating rats causes a slight but significant increase in UCP mRNA. Expression of mRNA for subunit II of cytochrome c oxidase (COII) decreased to half that of virgin control in late pregnancy and during lactation. Whereas COII mRNA expression is in step with the known modifications of brown-fat mitochondria content during the breeding cycle of the rat, UCP mRNA expression appears to be diminished much earlier than the mitochondrial proton-conductance-pathway activity. On the other hand, the reactivity of brown fat to increase expression of UCP and COII mRNAs in response to acute cold or noradrenaline treatment is not impaired during lactation.

Adipose Tissue, Brown↗