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C Vives

Publications and source records attributed to C Vives.

At least 19 recordsLinked to original sources
PubMed2002

Nutritional regulation of glucose-6-phosphatase gene expression in liver of the gilthead sea bream (Sparus aurata).

To examine the role of glucose-6-phosphatase (G6Pase) in glucose homeostasis in the diabetes-like experimental model of carnivorous fish, we analysed postprandial variations and the effect of starvation, ration size and diet composition on the regulation of G6Pase expression at the enzyme activity and mRNA level in the liver of gilthead sea bream (Sparus aurata). G6Pase expression increased in long-term starved or energy-restricted fish. In contrast to data reported for other fish species, short-term regulation of G6Pase expression was found in regularly fed S. aurata. G6Pase mRNA levels were lowest between 4 and 15 h after food intake, whereas minimal enzyme activity was observed 10-15 h postprandially. Alterations of plasma glucose levels affect G6Pase in mammals. However, the carbohydrate content of the diet did not affect hepatic expression of G6Pase in S. aurata, suggesting that a different molecular mechanism is involved in the control of G6Pase expression in fish. Although G6Pase was unaffected, high-carbohydrate low-protein diets increased glucokinase (GK) expression and thus allowed a metabolic adaptation favouring glycolysis over gluconeogenesis. Interestingly, only the nutritional conditions that promoted variations in the blood glucose levels resulted in changes in the hepatic expression of G6Pase. These findings indicate a concerted regulation of G6Pase and GK expression and suggest that the direction and rate of the glucose-glucose-6-phosphate substrate cycle flux is finely regulated in the liver of S. aurata, challenging the role attributed to deficient regulation of G6Pase or GK expression in the low ability of carnivorous fish to metabolize glucose.

Animals↗
PubMed1999

Molecular spectra of HPRT deletion mutations in circulating T-lymphocytes in Fanconi anemia patients.

The principal cellular feature of Fanconi anemia (FA), an inherited cancer prone disorder, is a high level of chromosomal breakage, amplified after treatment with crosslinking agents. Three of the eight genes involved in FA have been cloned: FANCA, FANCC and FANCG. However, their biological functions remain unknown. We previously observed an excessive production of deletions at the HPRT locus in FA lymphoblasts belonging to the relatively rare complementation group D(1) and an increased frequency of glycophorin A (GPA) variants in erythrocytes derived from FA patients (2). In thi study, we examined the molecular nature of 31 HPRT mutations formed in vivo in circulating T-lymphocytes isolated from 9 FA male patients. The results show that in all FA patients investigated the deletions are by far the most prevalent mutational event in contrast to age matched healthy donors, in which point mutations predominate. The complementation group in the FA patients examined in the present study has not yet been defined. However, knowing that mutations in the FANCA and FANCC gene are found to be involved in at least 70% of the FA patients, it can be expected that the excessive production of deletions is a general feature of the FA phenotype. In addition, the spectrum of HPRT deletions observed in FA patients differs from that of healthy children: there is a high frequency of 3'-terminal deletions and a strikingly low proportion of V(D)J mediated events. Based on previous findings, a decreased fidelity of coding V(D)J joint formation (3) and an inaccurate repair of specific DNA double strand breaks via Non-Homologous End Joining (4), we propose that FA genes play a role in the control of the fidelity of rejoining of specific DNA ends. Such a defect may explain several basic features of FA, such as chromosomal instability and deletion pronenness.

Adolescent↗
PubMed1999

Coordinated modulation of the fibroblast growth factor dual receptor mechanism during transformation from human colon adenoma to carcinoma.

Basic fibroblast growth factor (bFGF) is dependent on heparan sulphate for its ability to activate the cell surface signal transducing receptor. We have investigated the FGF dual receptor mechanism in a novel model of the transformation from human colon adenoma to carcinoma in vitro. Reverse transcription-polymerase chain reaction showed that mRNA for FGF receptors 1 and 2 were expressed in both the adenoma and carcinoma cells whereas immunocytochemistry showed that the expression of the FGF R1 was reduced significantly in the carcinoma cells. We have reported previously that the composition and sequence of human colon adenoma and carcinoma heparan sulphate (HS) differ in a defined and specific manner. The functional significance of these changes was assessed by affinity co-electrophoresis, which showed that the affinity of adenoma HS for bFGF was 10-fold greater than that of the carcinoma HS (Kd 220 nM vs. 2493 nM, respectively). In addition, Northern studies of the expression of syndecan 1 and 4 mRNA showed that proteoglycan core protein expression was reduced significantly in the carcinoma cells. These findings were associated with a reduced biological response to bFGF in the carcinoma cells that could be partially reversed by the addition of exogenous heparin, suggesting that both the proteoglycan and signal transducing receptor control the cells' response to bFGF.

Adenoma↗
PubMed1998

[Staff certification for mobile blood collection units].

Training and official acknowledgment of the competence of each staff member are essential to the quality and safety of collected blood products prepared and delivered by a blood transfusion center. A procedure was created to indicate in detail the methods employed to implement such accreditation. Based on individual training according to activity, it defines for each type of activity (secretary, physician, collector, driver) the required theoretical and practical knowledge of his/her position. Accreditation, consisting of assessment of the degree of competence attained in these areas of responsibility, was applied to the members of mobile blood collection teams in 1995. No major deficiency was detected, and this certification was well accepted by the staff. In order to complete this initial accreditation, blood collection abnormalities (inadequate blood volumes, clots or defective welding of tubing) were assessed for each collector individually. Comparison of these abnormalities in qualified nurses and laboratory technicians with a blood collection diploma showed no differences. On the other hand, significantly higher numbers of abnormalities were found in intermittent as compared to regular collectors and in senior as compared to new collectors. The applied corrective measures led to obviation of differences and improvement in performance. In 1996, in the first individual evaluation of medical selection carried out by each physician, discrepancies of one to 20 donors (0.7-14.2%) were observed from one doctor to another in the frequency of elimination of candidates for blood donation after the medical interview. Regular meetings with physicians resulted in reducing these discrepancies to one to 3.1 donors (4.6-14.1%) in 1997. In conclusion, the association of an initial accreditation procedure with an individual follow-up of work quality allowed satisfactory assessment of the training and competence of staff members. This kind of method could be extended to those working in other fields of transfusion medicine.

Allied Health Personnel↗
PubMed1998

[Quality control of homologous blood collection activities: 5 years' experience].

Quality control (QC) of blood collection activities for transfusion is a regulatory requirement. The authors report on their experience in this field over the past 5 years. In their institution, this QC is based on both the recording and analyzing of predefined data, as well as the search for an active collaboration from each person involved in these activities. QC of medical selection relies on the assessment of several associated criteria: effectiveness of the information given to blood donors for recruitment, preparation of the medical interview and encouragement to perform regular donations; frequency of donors deferred after the medical interview; frequency of biological abnormalities detected at donation; results of the inquiries into the corresponding medical interviews following adverse transfusion reactions. The quantitative and qualitative evaluation of blood collection permits assessment of the quality of the blood collection program, collection procedures and directly derived blood products. Quality assessment of facilities and equipment is also included in this QC. Results have been improving in recent years, especially regarding medical selection. In particular, an increase in the mean donation rate of donors, a decrease in biological abnormalities detected at donation and an absence of adverse transfusion reactions attributed after inquiry to an inadequate medical interview have been noticed. A decrease in both shortage and outdating of labile blood products likewise indicates an improvement of blood collection planning. However, this QC reveals deficiencies in the information given to donors and a lack of analysis of the data specific to first time donors. In order to further improve the efficiency of QC, these results now require comparison with similar data collected on a nation-wide scale.

Anemia↗
PubMed1998

[Evaluation of measurements intended to develop regularity of blood donation].

An increase in the regularity of blood donation is desirable for two main reasons. First, the lower incidence of viral disease markers in regular donors when compared to first donors could help to reduce risks of transmissible diseases. Second, a higher frequency of donation could contribute to a more satisfactory supply of blood products. Two measures implemented with the aim of increasing the regularity of blood donation were evaluated: (i) an increase in the annual frequency of blood collection by mobile teams at collection sites, and (ii) a "next donation document" given to each donor indicating the earliest possible date of the next donation. The regularity index was calculated as the mean number of cellular donations (whole blood and platelet apheresis) per donor per year, over two consecutive periods: 1-7-1993-30-6-1994 (P1) and 1-7-1994-30-6-1995 (P2). The junction of these two periods corresponded to the date of introduction of the "next donation document" and to the time of reinforcement of the mobile collection frequency. First donors in either period were not taken into account in the study. A significant relationship was observed between the annual frequency of mobile collection and the average number of donations per donor (comparison test of two means on large samples, p < 0.001 in all the cases excepted those of stable mobile collection numbers). Thus, in the first period, the average donation rate was the lowest on sites having only one mobile collection per year (M: 1.55, W: 1.38) and the highest on sites with five mobile collections per year (M: 2.05, W: 1.71). These average numbers significantly increased in the second period as compared to the first (M: +4.8%, W: +1.8%; comparison test of two means from paired series, p < 0.001), as did the yearly frequency of mobile blood collections (+9.2%). On the other hand, the "next donation document" was not associated to any change in the regularity index. The results of this study therefore showed an increase in the frequency of visits of mobile collection teams to be the main factor leading to an improvement in the regularity of blood donation. Moreover, this evolution was associated with a decrease in the incidence of viral markers detected at donation.

Adult↗
PubMed1997

Overproduction and purification of an agarase of bacterial origin.

The agarase gene from Streptomyces coelicolor has been cloned in the non-producer bacterium Streptomyces lividans under the control of its own set of promoters and under the control of a heterologous promoter that is functional only during exponential growth. The best level of overproduction was obtained when the strain containing the natural gene was cultivated in fed batch with mannitol as carbon source. The protein, with a relative molecular mass of 32 kDa, has been purified following an affinity purification method. Contaminating activities seem to be absent from the purified enzyme preparation that can be used to purify DNA from agarose gels.

Bacterial Proteins↗
PubMed1985

Isomers of broparoestrol and antiestrogen action: comparison with tamoxifen.

This study compares the relative biological potencies of a known antiestrogen tamoxifen to two triarylethylene compounds which have been shown previously to be potent inhibitors of rodent mammary tumorigenesis. Based on a) uterotrophic and anti-uterotrophic tests, b) indexes of cellularity, and c) protein content, these studies indicate that the trans, as well as the cis, isomers of bromotriphenylethylene are partial estrogen antagonists with no estrogenic effects in rat uteri and partial agonists in mouse uteri, whereas tamoxifen shows partial antiestrogenic/estrogenic effects in rats and is fully estrogenic in mice.

Animals↗
PubMed1980

Inhibition of prolactin-induced mammary cancer in C3Hf (XVII) mice with the trans isomer of bromotriphenylethylene.

C3Hf (XVII) mice never develop spontaneous mammary tumors. However, the transplantation of an isologous pituitary gland under their kidney capsule is followed by a 10-fold increase in serum and pituitary prolactin content (180 ng/ml and 20 micrograms/mg of tissue, respectively), concomitant with an increase of prolactin receptors in mammary glands. Under these conditions, mammary tumors appear in 90% of the mice. If a racemic brominated triphenylethylene, i.e., broparestrol, is administered, serum and pituitary prolactin decrease rapidly (10 ng/ml and 4 micrograms/mg of tissue, respectively), and prolactin receptors in the mammary gland are markedly reduced. This compound also inhibits the development of normal mammary glands, prevents mammary carcinogenesis, and unexpectedly causes a significant atrophy of the ovaries. Our study confirms that prolactin is a key hormone involved in murine mammary carcinogenesis and that it can act directly on the mammary gland by stimulaing the level of its own receptor.

Animals↗
PubMed1980

Interactions between prolactin and ovarian secretions during mammary tumorigenesis in the mouse.

The plasma levels of ovarian steroids and the steroid binding capacity in the cytosol of mammary glands have been determined in the low-mammary-tumor C3H/f (XVII) mice. Implantation of a pituitary under the kidney leads to an increase of all these parameters as well as a high mammary tumor incidence. Simultaneous administration of the trans isomer of broparestrol (TBP) leads to a decrease of all the parameters.

Animals↗
PubMed1978

Dose-effect studies on estrogen induced mammary cancers in mice.

Castrated male (C3H X RIII) F1 mice were treated with graded doses of estradiol-17-beta and estrone in a life-span experiment. Estradiol-17-beta incorporated into paraffin pellets was implanted under the skin for continuous resorption. These pellets contained 1 microgram, 2.5 microgram, 5 microgram, 10 microgram or 100 microgram of hormone. Estron was given orally, mixed with the food at 3 daily dosages: 0.06 microgram, 0.6 microgram and 6 microgram. Although the smallest dosages of both hormones induced vaginal estrus in castrated females, they did not produce mammary tumors. The mammary tumor incidence reached progressively almost 100% in response to the increase of the hormonal dosages. The absence of effect of low doses of estrogen in mice is compared with the absence of an excess of breast cancers among women using oral contraceptives.

Animals↗
PubMedDate not supplied

[Intimate partner violence in Spain].

OBJECTIVE: To estimate mortality and the incidence of formal complaints of intimate partner violence (IPV) by age groups and Spanish provinces. METHODS: We performed a descriptive, epidemiological study of murders by intimate partners registered in the database of the Divorced and Separated Women's Federation (1998-2001) and of formal complaints of IPV in The Home Affairs database (1997-2000). The percentage of increase in formal complaints and deaths and the individual risk of dying from IPV and of reporting this crime was calculated through the simple accumulative method, specific mortality rates by age, average rates by provinces, and specific incidence rates of formal complaints of IPV by provinces. Finally, a simple regression analysis was performed to assess the relation between mortality and the incidence of formal complaints of IPV. RESULTS: Between the first and the last year of the study, formal complaints increased by 27% and murders increased by 49%. In Spain, during the period analyzed, one out of every 100,000 women was murdered by an intimate partner and one out of every 200 women reported IPV. Women aged 22-41 years and those aged 82-86 years presented the highest rates of mortality from IPV. Mortality from IPV and the incidence of formal complaints of IPV showed no clear geographical pattern. No correlation between mortality and the incidence of formal complaints of IPV by provinces was found (corrected r2 = 0.016). CONCLUSIONS: IPV is an increasing public health problem in Spain. There seems to be a bimodal curve by age in mortality from IPV, but no geographical patterns in mortality and the incidence of formal complaints of IPV or between the provinces with the highest incidence of formal complains and those with highest mortality were observed.

Adolescent↗