PubMed Health⌕ Search

Biomedical subjects

C Tomás

Publications and source records attributed to C Tomás.

At least 19 recordsLinked to original sources
PubMed2004

Micro-environmental and socio-demographic determinants of childhood obesity.

AIM: To review the available data in Spain about the socio-demographic and home environmental determinants in children and adolescents. METHOD: Review of the main studies conducted in Spain that have analysed the relationship between overweight and socio-economic and environmental determinants in children and adolescents. RESULTS: In children aged 6-7 y from Aragon (Spain), the socio-demographic determinants of childhood overweight were size of municipality, year of examination, gender, and province; in adolescents aged 13-14 y, the socio-demographic determinants were year of examination, type of school, size of municipality, gender, and province; overweight showed a significant positive main effect with public schools and low municipality size. In a nationally representative sample of Spanish adolescents from 13 to 18.5 y (AVENA Study), there was a significant relationship between overweight and socio-economic status in males but not in females; in males, the lowest overweight prevalences were observed in both extreme socio-economic groups; moreover, overweight prevalences increased when socio-economic status decreased, from the high to the medium-low socio-economic group. The studied variables related with family environment did not show any significant effect in overweight prevalence. CONCLUSION: Better knowledge of the relationship between social class and childhood obesity would lead to clearer hypotheses for the relationship in adults and might improve the preventive measures by identifying children at risk.

Adolescent↗
PubMed2002

Improved detection of liver metastases with contrast-enhanced wideband harmonic imaging: comparison with CT findings.

OBJECTIVE: To evaluate the capability of contrast-enhanced wideband harmonic imaging (WHI) to detect liver metastases in comparison with fundamental B-mode US and postcontrast CT. METHODS: We studied 27 patients with hepatic metastases from different malignancies with conventional B-mode sonography, WHI 3 min after injection of contrast agent (Levovist(R) 2.5 g, 300 mg/ml) and postcontrast helical CT (HCT). The number and location of the lesions and the smallest lesion for each patient were noted by two different observers and compared. RESULTS: Both readers recorded an increase in the number of lesions in harmonic mode compared with conventional B-mode in all 27 patients with hepatic metastases with a mean increase in both observers from 9.3 lesions with B-mode to 18.8 lesions with WHI. The smallest lesions were detected with WHI when compared with conventional US and HCT (2 mm with WHI, 5 mm with B-mode and 5 mm with CT). WHI detected more lesions than conventional US or HCT. CONCLUSIONS: Contrast-enhanced WHI seems superior to conventional US and HCT for the detection of hepatic metastases, specially for those nodules under 1 cm of diameter.

Adult↗
PubMed2001

Morbidity of 10 110 hysterectomies by type of approach.

BACKGROUND: Since the late 1980s, the option of laparoscopic hysterectomy has raised questions about the most suitable approach to hysterectomy. METHODS: To evaluate the influence of the type of approach, in causing or avoiding certain complaints in hysterectomies a prospective nationwide study was conducted comprising all hysterectomies for benign disease performed in Finland during 1996. The primary outcomes of interest were the operation-related morbidity, common surgical details and post-operative complications. RESULTS: A total of 10 110 hysterectomies, including 5875 abdominal, 1801 vaginal and 2434 laparoscopic operations showed a low rate of overall complications, 17.2, 23.3 and 19.0% respectively. Infections were the most common complications with incidences of 10.5, 13.0 and 9.0% in the abdominal, vaginal and laparoscopic group respectively. The most severe type of haemorrhagic events occurred in 2.1, 3.1 and 2.7% in the abdominal, vaginal and laparoscopic group respectively. Ureter injuries were predominant in laparoscopic group [relative risk (RR) 7.2 compared with abdominal] whereas bowel injuries were most common in vaginal group (RR 2.5 compared with abdominal). Surgeons who had performed >30 laparoscopic hysterectomies had a significantly lower incidence of ureter and bladder injuries (0.5 and 0.8% respectively) than those who had performed < or =30 operations (2.2 and 2.0% respectively). A decreasing trend of bowel complications was also seen with increasing experience in vaginal hysterectomies. CONCLUSIONS: This large-scale observational study on hysterectomies provides novel information on operation-related morbidity of abdominal, vaginal or laparoscopic approach. The results support the importance of the experience of the surgeon in reducing severe complications, especially in laparoscopic and vaginal hysterectomies.

Adult↗
PubMed2001

One versus two embryo transfer after IVF and ICSI: a randomized study.

BACKGROUND: The main reason for adverse treatment outcome in assisted reproduction is the high rate of multiple pregnancies. The only strategy to avoid dizygotic twins is to transfer one embryo at a time. METHODS: A total of 144 women, who had had at least four good quality embryos available after IVF/intracytoplasmic sperm injection (ICSI) and who had no more than one previous failed treatment cycle, were randomized to have either one or two embryos transferred. The treatment outcomes including those after frozen embryo transfer were compared between these groups. RESULTS: The clinical pregnancy rate per transfer was 32.4% in the one embryo transfer group and 47.1% in the two embryo transfer group, the difference being not significant. Eleven twin deliveries (n = 39) occurred in the two embryo transfer group and there was one pair of monozygotic twins in the one embryo transfer group. The cumulative pregnancy rate per patient after transfer of fresh and frozen embryos was 47.3% in the one embryo transfer group and 58.6% in the two embryo transfer group. CONCLUSIONS: Our results indicate that among women who have good quality embryos in their first IVF/ICSI, good treatment results can be achieved. They support the idea of changing embryo transfer policy towards one embryo transfer without any remarkable decrease in the success rate, while dizygotic twins can be avoided.

Adult↗
PubMed2000

Spatial and temporal variability of ground-level ozone in Castilla-León (Spain).

Ozone is a secondary air pollutant that has received extensive attention in the literature, mainly because of the adverse effects that exposure to it can cause, particularly in vegetation during the growing season. Because meteorological conditions strongly influence the efficiency of photochemical processes leading to ozone formation and destruction, ground-level ozone air pollution is currently being considered as a regional-scale phenomenon rather than a local one. This role of O3 as a regional-scale pollutant often implies the handling of large data sets in order to obtain information about its spatial and temporal variability patterns over a given broad region. Rotated principal component analysis (RPCA) is known to be one of the most powerful mathematical tools that can be used to achieve this aim. RPCA was applied in this paper to the summer and winter hourly time series of ground-level O3, concentrations recorded during 2 consecutive years (1996-1997) at 26 urban and suburban sites in Castilla-León (Spain). This procedure permitted the identification of different subregions where O3 concentrations show different spatio-temporal variability patterns. These variability patterns are mainly associated with the interaction of regional-level meteorological and anthropogenic factors. Some differences between winter and summer patterns were also found.

Air Pollutants↗
PubMed2000

Prevalence of the C282Y mutation for haemochromatosis on the Island of Majorca.

The C282Y mutation of the HFE gene has been reported to be present in most of the patients with hereditary haemochromatosis (HH) of Northern European ancestry. HH affects approximately 1/300 individuals, but it is not evenly distributed in the different European countries. In the present study, polymerase chain reaction (PCR) and restriction-enzyme digestion were used to analyse the frequency of the most important mutation in haemochromatosis (C282Y) in subjects from Majorca (Balearic Islands, Spain) and patients with haemochromatosis. The results were compared with other studies from Spain and Europe. A total of 420 Majorcan chromosomes were analysed and the C282Y mutation was observed at a frequency of 2.62%+/-0.8 (11 heterozygotes: eight men and three women). In the group of hereditary haemochromatosis probands, 13 out of 14 were homozygous for the C282Y mutation. In the distribution of the C282Y mutation, a north-west to south-east cline was detected, supporting the Celtic origin of this mutation.

Adult↗
PubMed1999

The prevalence of polycystic ovaries in healthy women.

BACKGROUND: To study the prevalence of polycystic ovaries (PCO) in women of reproductive age. METHODS: A total of 189 healthy volunteers aged 20-45 years were examined. The subjects were divided into two groups according to age: < or =35 and > or =36 years. Transvaginal ultrasonography was performed and blood samples were collected on cycle day 1-6. RESULTS: The prevalence of PCO in the entire study population was 14.2% (27/189). In the age group of < or =35 years the prevalence was 21.6% (19/88) and in the age group of > or =36 years 7.8% (8/101). Compared to women with normal ovaries, those with PCO had significantly higher serum testosterone (T) concentrations. Women with PCO tended to have lower serum FSH concentrations and higher LH/FSH ratios than controls. Women with PCO had significantly more irregular cycles (44% vs. 19%, p=0.001) and problems in conceiving (25.9% vs. 9.2%, p=0.01) than women with normal ovaries. CONCLUSIONS: The findings demonstrate that the prevalence of PCO in healthy women varies with age, being more common among women aged < or =35 years than in those aged > or =36 years. Although the hormonal parameters and clinical findings among women with PCO mimicked those of PCOS, it remains unclear if these women will later develop full-blown syndrome.

Adult↗
PubMed1999

Insulin sensitivity during postmenopausal hormone replacement with transdermal estradiol and intrauterine levonorgestrel.

BACKGROUND: The study was devised to measure the effect of intrauterinely delivered levonorgestrel and transdermal estradiol on insulin sensitivity in postmenopausal women and compare this effect with that induced by transdermal estradiol alone. METHODS: An open, prospective, comparative study of healthy postmenopausal women without earlier use of hormone replacement therapy. The estrogen therapy group consisted of eight hysterectomized women, who used a transdermal patch delivering a daily dose of 50 microg of estradiol continuously for 6 months. The estrogen-progestin therapy group consisted of 13 women with an intact uterus, who received a simultaneous combination of a transdermal patch and a levonorgestrel (20 microg/day) intrauterine system for the same length of time. Fasting plasma concentrations of glucose, insulin and C-peptide and an insulin tolerance test were used to measure glucose metabolism and insulin sensitivity. RESULTS: Neither therapy changed the fasting plasma levels of glucose, insulin or C-peptide. Transdermal estrogen improved insulin sensitivity by 22%, as measured by an insulin tolerance test, while a small increase of 3.6% was observed using the combination therapy. CONCLUSIONS: Transdermal estradiol improves insulin sensitivity in healthy postmenopausal women. Combining intrauterine levonorgestrel to transdermal estradiol reverses this effect. This combination does not, however, seem to induce insulin resistance.

Administration, Cutaneous↗
PubMed1998

Low pregnancy rate is achieved in patients treated with intracytoplasmic sperm injection due to previous low or failed fertilization in in-vitro fertilization.

The main indications for intracytoplasmic sperm injection (ICSI) are severe male factor and fertilization failure or a low fertilization rate in previous in-vitro fertilization (IVF) treatments. The fertilization and pregnancy rates after ICSI, however, are seldom reported separately for these two different indications. The aim of this study was to compare the treatment outcome and pregnancy rate after ICSI between 65 patients with previous failed fertilization or a low fertilization rate without male factor, and 219 patients with a primary male factor. From the 2726 oocytes collected, 2087 (77%) were micro-injected and 1355 (65%) achieved normal fertilization. The oocyte fertilization rate was similar in the group with previous failed fertilization or a low fertilization rate and the group with a male factor (65 and 65% respectively), as was the cleavage rate of normally fertilized oocytes (92 and 94% respectively). Despite the similar fertilization and cleavage rates and the similar number and morphological quality of embryos transferred in both groups, the pregnancy rate was significantly lower (P < 0.05) in the group with previous failed fertilization or a low fertilization rate than in the group with a male factor (19.6 versus 33.5% respectively; 95% confidence intervals for the difference, 2-26%). The implantation rate was also lower (P = 0.01) in patients with previous failed fertilization or a low fertilization rate (9.6%) than in the group with a male factor (19.5%). We conclude that patients with previous failed fertilization or a low fertilization rate in standard IVF without male factor have a significantly smaller chance of becoming pregnant after subsequent ICSI than patients with a primary male factor. This poor outcome probably reflects intrinsic oocyte defects not bypassed by ICSI.

Adult↗
PubMed1998

Airborne grass (Poaceae) pollen in southern Spain. Results of a 10-year study (1987-96).

This work reports an exhaustive study of the aerobiology of the Gramineae in Seville, Spain, which is typical of coastal Mediterranean areas. Sampling was done with a Cour trap installed on the roof terrace of the School of Pharmacy, Seville, from 1987 to 1996, both inclusive. The climatic pattern of that period was characterized by two exceptionally wet years (1989 and 1996), between which were 5 consecutive years of drought (1990-5). This typically Mediterranean climate affects grass aerobiology. The annual amounts of total grass pollen are low, never exceeding 2500 grains/m3. The start, length, and intensity of the pollen season are significantly correlated with preseasonal meteorologic factors (precipitation and temperature), but intraseasonal meteorologic conditions have no effect on the three variables. The relationships are stated by three equations that, while further years of observations are anticipated, can be considered models to forecast the characteristics of the pollen season: the starting date depends on the mean temperatures of January and February, and the length and intensity of the season depend on the rainfall between the beginning of January and the starting date of the season. For the study period, the weekly concentrations (pollen curves) throughout the year showed no typical pattern of variation over the years, so that it was impossible to make mid- and long-term forecasts of the variation in weekly concentration. The most noteworthy aspects of grass pollen curves are a long pollen season, which starts in February or March and lasts until September or October; peaks of higher concentration (> 100 grains/m3) in May and June, associated with increases in temperature and absence of precipitation; and other peaks in the summer months that may be as high as the spring peaks.

Air Pollutants↗
PubMed1998

Decreased serum leptin concentrations during metformin therapy in obese women with polycystic ovary syndrome.

Previous studies have suggested that metformin is clinically useful in the treatment of polycystic ovary syndrome (PCOS). The aim of this study was to evaluate whether the improvement of ovarian function achieved by metformin therapy is associated with changes in leptin concentrations. Twenty-six obese women with PCOS were treated with 500 mg metformin, x 3 daily, for 2 months; and 12 women continued the therapy for 4-6 months. A significant decrease in the serum leptin level was observed after 2 months of treatment in the whole study group (29.2 +/- 12.7 ng/mL vs. 25.7 +/- 10.9 ng/mL, P = 0.03). In the 12 women treated for 4-6 months, the mean serum leptin concentration decreased after 2 months (38.6 +/- 9.3 ng/mL vs. 30.2 +/- 8.1 ng/mL; P = 0.004) but slightly increased after 4-6 months of treatment (33.4 +/- 15.7 ng/mL; not significant). These results indicate that insulin sensitizing therapy with metformin decreases the leptin concentrations in obese PCOS women.

Adult↗
PubMed1997

Comparison of fallopian tube sperm perfusion with intrauterine insemination in the treatment of infertility.

OBJECTIVE: To compare the efficacy of fallopian tube sperm perfusion utilizing a Foley catheter technique with standard IUI. DESIGN: Randomized controlled study. SETTING: The infertility units of the University Central Hospital and the Family Federation of Finland, Oulu, Finland. PATIENT(S): One hundred infertile women with unexplained factor, minimal to mild endometriosis, mild male factor, or ovarian dysfunction, undergoing 50 IUI and 50 fallopian tube sperm perfusion cycles stimulated by clomiphene citrate and hMG. INTERVENTION(S): Thirty-six hours after hCG administration, patients were randomized to either the IUI group (group 1, 50 patients and cycles) or the fallopian tube sperm perfusion group (group 2, 50 patients and cycles). Intrauterine insemination was performed using a standard method and fallopian tube sperm perfusion with a pediatric Foley catheter, which prevents the reflux of sperm suspension. MAIN OUTCOME MEASURE(S): Number of clinical pregnancies. RESULTS(S): The fallopian tube sperm perfusion method using a Foley catheter technique was easy to perform and convenient for the patients. The overall pregnancy rate per cycle was 8% for fallopian tube sperm perfusion and 20% for IUI, a difference that was not significant. CONCLUSION(S): The fallopian tube sperm perfusion method using a Foley catheter offers no advantage in comparison with the conventional IUI technique.

Adult↗
PubMed1997

Long gonadotrophin releasing hormone agonist/human menopausal gonadotrophin protocol for ovarian stimulation in intrauterine insemination treatment.

OBJECTIVE: This prospective study was undertaken to examine the usefulness of a long gonadotrophin releasing hormone agonist (GnRH-a)/human menopausal gonadotrophin (hMG) protocol in intrauterine insemination (IUI) treatment. The results were compared to those of clomiphene citrate (CC)/hMG/IUI. STUDY DESIGN: Seventy-five patients were recruited to a GnRH-a/hMG group (group 1) while 88 patients underwent CC/hMG stimulation and served as controls (group 2). The study subjects were stimulated with a long GnRH-a/hMG regimen. IUI was performed 36 h after the administration of human chorionic gonadotrophin. RESULTS: The number of preovulatory follicles, the thickness of endometrium and sperm parameters were similar in both groups. The hMG requirements were significantly higher in group 1 than in group 2 (21.2 +/- 5.1 vs. 8.1 +/- 3.1 ampoules). The pregnancy rate was 20% in group 1 and 12.5% in group 2, the difference being not significant. CONCLUSION: The pregnancy rates were not significantly different between the GnRH-a/hMG/ IUI and CC/hMG/IUI groups. In addition, GnRH-a/hMG stimulation is notably more expensive than CC/hMG, and for these reasons, GnRH-a/hMG stimulation is not cost-effective in routine IUI therapy.

Adult↗
PubMed1996

Seasonal changes in pituitary function: amplification of midfollicular luteinizing hormone secretion during the dark season.

OBJECTIVE: To analyze the effect of season on the pulsatility of gonadotropin secretion in women living in an area with a large annual variability in daylight length. DESIGN: A prospective study. Pulse studies were carried out in each subject during both the dark and light season. SETTING: The gynecologic endocrine research unit of the University Central Hospital of Oulu. PARTICIPANTS: Eleven ovulatory, healthy women volunteering for the study. INTERVENTIONS: Serum samples were collected at 10-minute intervals for 6 hours on days 7 to 9 of the cycle. MAIN OUTCOME MEASURES: Serum LH and FSH concentrations were measured and the data were analyzed with an algorithm computer-based program. RESULTS: The mean area of LH pulses analyzed was significantly higher during the dark season than the light season (49.1 +/- 3.1 versus 38.5 +/- 1.7 mIU/mL; conversion factor to SI unit, 1.00), while in the amplitude (1.9 +/- 0.1 versus 1.8 +/- 0.1 mIU/mL), number of pulses (5.2 +/- 0.3 versus 4.4 +/- 0.6), and the mean level (9.6 +/- 0.5 versus 9.4 +/- 0.9 mIU/mL) the difference did not reach statistical significance. The number (5.2 +/- 0.5 versus 5.2 +/- 0.4,), amplitude (1.0 +/- 0.05 versus 1.1 +/- 0.07 mIU/mL; conversion factor to SI unit, 1.00), area (29.9 +/- 2.4 versus 29.6 +/- 3.1 mIU/mL), and the mean level of FSH (5.4 +/- 0.6 versus 6.0 +/- 0.8 mIU/mL) during the dark and light seasons were identical, showing no seasonal variability. CONCLUSIONS: The results indicate increased pituitary LH secretion in the midfollicular phase during the dark season that may be related to increased melatonin secretion and decreased ovarian activity at this time of the year.

Adult↗
PubMed1995

Macrophage colony-stimulating factor 1, a clinically useful tumor marker in endometrial adenocarcinoma: comparison with CA 125 and the aminoterminal propeptide of type III procollagen.

OBJECTIVE: We investigated the clinical utility of macrophage colony-stimulating factor 1 versus CA 125 and the aminoterminal propeptide of type III procollagen in endometrial carcinoma. STUDY DESIGN: Serum levels of the three substances were measured in 159 patients with untreated endometrial adenocarcinoma and in 24 patients treated with cytotoxic chemotherapy for recurrent endometrial adenocarcinoma. RESULTS: Initial concentrations of colony-stimulating factor 1, CA 125, and the aminoterminal peptide of type III procollagen were above the normal range in 73%, 11%, and 27%, respectively, of the patients. Colony-stimulating factor 1 levels correlated with those of the aminoterminal peptide of type III procollagen (r = 0.3, p = 0.002) and CA 125 (r = 0.20, p = 0.036) in the total group and with those of the aminoterminal peptide of type III procollagen in stage I and II patients (r = 0.3, p = 0.0023). Colony-stimulating factor 1 levels correlated significantly with tumor grade, whereas those of CA 125 and the aminoterminal peptide of type III procollagen correlated more closely with clinical stage. Mean colony-stimulating factor 1 levels (9.6 vs 7.7 ng/ml, p = 0.04) and the frequency of elevated CA 125 levels (31% vs 8%, p = 0.048) were higher in patients with poor prognosis than in those with good prognosis. Colony-stimulating factor 1, the aminoterminal peptide of type III procollagen, and CA 125 levels were useful in monitoring clinical behavior of the disease in 88%, 79%, and 63% of the cases, respectively. Levels of all three markers rose with disease progression, whereas colony-stimulating factor 1 and the aminoterminal peptide of type III procollagen fell with clinical responses to therapy. CONCLUSION: Elevated serum colony-stimulating factor 1 levels were the most accurate indicator of the presence and activity (progression, stabilization, or regression) of primary or recurrent disease. Accuracy was not further enhanced by measurement of CA 125 or the aminoterminal peptide of type III procollagen levels.

Adenocarcinoma↗
PubMed1995

Intrafollicular insemination for the treatment of infertility.

The effectiveness of intrafollicular insemination (IFI) for the treatment of non-tubal infertility was investigated in a pilot study. A total of 50 infertility patients with normal tubal function verified by laparoscopy or hysterosalpingography were stimulated with clomiphene citrate/human menopausal gonadotrophin. Washed spermatozoa were injected into one to three pre-ovulatory follicles via vaginal puncture 12 or 30 h after human chorionic gonadotrophin administration. Natural progesterone was given for luteal support. The IFI procedure was technically very simple and convenient for the patient and no complications were recorded. One normal intra-uterine pregnancy resulted. The results indicate that by comparsion with other assisted reproductive technologies IFI is very inefficacious for treating non-tubal infertility. Our data suggest that the intrafollicular environment in the preovulatory period is not favourable for fertilization.

Adult↗
PubMed1994

Nuclear response of pancreatic islets to interleukin-1 beta.

The mechanisms by which interleukin-1 (IL-1) exerts destructive action on the pancreatic islet beta-cells remain elusive. Fragmentation of DNA leading to the activation of poly(ADP-ribose) synthetase was investigated in the present study, by assessing the nuclear response to cytokines in rat pancreatic islets. Nuclear fractions display Mg(2+)-dependent poly(ADP-ribose) synthetase activity catalyzing the incorporation of [adenine-U-14C]NAD, with Ka and Km for Mg2+ and NAD amounting to 0.86 mM and 0.43 mM, respectively. Exposure of the nuclear fraction to rIL-1 beta (10 IU/ml) provoked DNA strand breaks and increased nuclear poly(ADP-ribose) synthetase activity (148.4%, P < 0.01). In intact islets, this nuclear response was observed after 18 h culture in medium containing rIL-1 beta, with a concomitant decrease in NAD (88.5%). Brief periods of pre-incubation (90 min) with rIL-1 beta were unable to induce any nuclear activity. Under these conditions, the presence of IFN-alpha (24 U/ml) and TNF (120 U/ml) was necessary to induce a response to rIL-1 beta. Under the latter experimental conditions, a decrease in NAD content was also observed. The nuclear effects of IL-1 beta were modified by nicotinamide (10 mM), an inhibitor of poly(ADP-ribose) synthetase. It is thus conceivable that an increase in poly(ADP-ribose) synthetase activity together with DNA break is implicated in the beta cytotoxic effect of interleukin-1 beta.

Adenine↗