Influence of Post-Mortem Sperm Recovery Method and Extender on Unstored and Refrigerated Rooster Sperm Variables.

Many post-mortem sperm collection techniques have been described for mammalian species, but their use in birds is scarce. This paper compares the efficacy of two post-mortem sperm retrieval techniques - the flushing and float-out methods - in the collection of rooster sperm, in conjunction with the use of two extenders, i.e., L&R-84 medium and Lake 7.1 medium. To determine whether the protective effects of these extenders against refrigeration are different for post-mortem and ejaculated sperm, pooled ejaculated samples (procured via the massage technique) were also diluted in the above extenders. Post-mortem and ejaculated sperm variables were assessed immediately at room temperature (0 h), and after refrigeration at 5°C for 24 and 48 h. The flushing method retrieved more sperm than the float-out method (596.5 ± 75.4 million sperm vs 341.0 ± 87.6 million sperm; p < 0.05); indeed, the number retrieved by the former method was similar to that obtained by massage-induced ejaculation (630.3 ± 78.2 million sperm). For sperm collected by all methods, the L&R-84 medium provided an advantage in terms of sperm motility variables at 0 h. In the refrigerated sperm samples, however, the Lake 7.1 medium was associated with higher percentages of viable sperm, and had a greater protective effect (p < 0.05) with respect to most motility variables. In conclusion, the flushing method is recommended for collecting sperm from dead birds. If this sperm needs to be refrigerated at 5°C until analysis, Lake 7.1 medium is recommended as an extender.

Changes in thyroid function with age: results from the Pizarra population-based longitudinal study.

BACKGROUND: Results of studies examining the influence of age on thyroid function and TSH levels, in the absence of thyroid disease, remain controversial. The aim of this study was to determine the course of thyroid function over 11 years in a population with normal thyroid function. METHODS: This is a population-based prospective study started in 1995-1997 (first phase), and reassessed 6 (second phase) and 11 years later (third phase). RESULTS: The TSH and FT4 in the third phase were significantly increased (p=0.001 and p=0.001, respectively), with the values being higher particularly from the age of 50 years. In those persons with a baseline TSH≥1.2 and <3 µIU/mL, the OR of having a TSH of 3-5 µIU/mL in the third phase was 6.10 (p=0.004). In those with a baseline TSH≥3 and ≤5 µIU/mL, the OR of having a TSH of 3-5 µIU/mL in the third phase was 20.8 (p<0.0001). Similar results were found for FT4. CONCLUSION: In a population free of clinical thyroid disease, TSH and FT4 values rise over the years. This increase occurs in all age groups, but depends mainly on the basal concentrations of TSH and FT4.

Influence of Staining Method on the Values of Avian Sperm Head Morphometric Variables.

Computer-assisted systems for the assessment of sperm morphometry (ASMA systems) have been used successfully with several mammalian species. Unfortunately, they have so far been of little use for assessing bird semen, a consequence of the filiform shape of avian spermatozoa. This study compares two staining techniques (Hemacolor(®) and aniline blue staining) for the morphometric analysis of rooster and red-legged partridge spermatozoa as part of a computer-assisted light microscopy method. For both species, Hemacolor(®) staining provided a significantly higher percentage of measurable cells (93.7 ± 11.7% in roosters and 71.9 ± 15.3% in red-legged partridges). Hemacolor(®) also showed greater repeatability (lower coefficients of variation) for length and area in roosters' sperm and for width in the case of red-legged partridge's sperm. In the roosters, the Hemacolor(®) technique returned significantly (p < 0.05) larger sperm head width and area values than did the aniline blue technique, while the latter resulted in greater sperm head length values (p < 0.05). In the red-legged partridge, no differences were seen in the results for sperm head width and area provided by the two techniques, but aniline blue staining was associated with longer length measurements. In conclusion, the morphometric values recorded differed depending on the staining method and species. However, the Hemacolor(®) technique might be deemed the more appropriate for computerized sperm assessment systems as it provides larger percentages of measureable cells and shows greater repeatability.

Avoidance behaviour response and esterase inhibition in the earthworm, Lumbricus terrestris, after exposure to chlorpyrifos.

The avoidance response of earthworms to polluted soils has been standardised using a simple and low-cost test, which facilitates soil toxicity screening. In this study, the avoidance response of Lumbricus terrestris was quantified in chlorpyrifos-spiked soils, depending on the pesticide concentration and exposure duration. The inhibition of acetylcholinesterase (AChE) and carboxylesterase (CbE) activities was also determined as indirect measures of pesticide bioavailability. The effects of different chlorpyrifos concentrations were examined in a standardised test (two-chamber system) with 0.6, 3 and 15 mg/kg chlorpyrifos. A modification of the test involved a pre-exposure step (24, 48 or 72 h) in soils spiked with 15 mg/kg. In both protocols, earthworms were unable to avoid the contaminated soils. However, the esterase activities showed that all earthworms were exposed to chlorpyrifos. Acetylcholinesterase activity did not change in earthworms in the standardised behavioural test (0.58 ± 0.20 U/mg protein, mean ± SD; n = 72), whereas the CbE activity was significantly inhibited (62-87 % inhibition) in earthworms exposed to 3 and 15 mg/kg. In the modified test, earthworms had greatly inhibited AChE activity (0.088 ± 0.034 U/mg protein, n = 72), which was supported by reactivation of the inhibited enzyme activity in the presence of pralidoxime (2-PAM). Similarly, the CbE activity was significantly inhibited in earthworms with all treatments. This study suggests that the avoidance behaviour test for organophosphorus-contaminated soils could be supported by specific biomarkers to facilitate a better understanding of pesticide exposure and toxicity during this test.

Removal efficiency for emerging contaminants in a WWTP from Madrid (Spain) after secondary and tertiary treatment and environmental impact on the Manzanares River.

The effluents from wastewater treatment plants (WWTPs) can be an important contamination source for receiving waters. In this work, a comprehensive study on the impact of a WWTP from Madrid on the aquatic environment has been performed, including a wide number of pharmaceuticals and pesticides, among them those included in the European Watch List. 24-h composite samples of influent (IWW) and effluent wastewater after secondary (EWW2) and after secondary + tertiary treatment (EWW3) were monitored along two campaigns. Average weekly concentrations in IWW and EWW2 and EWW3 allowed estimating the removal efficiency of the WWTP for pharmaceutical active substances (PhACs). In addition, the impact of EWW3 on the water quality of the Manzanares River was assessed, in terms of PhAC and pesticide concentrations, through analysis of the river water collected upstream and downstream of the discharge point. After a preliminary risk assessment, a detailed evaluation of the impact on the aquatic environment, including a toxicological study and screening of pharmaceutical metabolites, was made for the seven most relevant PhACs: sulfamethoxazole, azithromycin and clarithromycin (antibiotics), metoprolol (antihypertensive), diclofenac (anti-inflammatory/analgesic), irbesartan (antihypertensive), and the antidepressant venlafaxine. Among selected PhACs, irbesartan, clarithromycin and venlafaxine presented moderate or high risk in the river water downstream of the discharge. Albeit no acute toxicity was detected, more detailed studies should be carried out for these substances, including additional toxicological studies, to set up potential sublethal and chronic effects on aquatic organisms.

Cryopreservation of testicular tissue from the dog (Canis familiaris) and wild boar (Sus scrofa) by slow freezing and vitrification: Differences in cryoresistance according to cell type.

Sperm cryopreservation is the most common procedure used to establish germplasm banks for endangered species - but sometimes sperm cells cannot be obtained. In such cases, freezing testicular tissue may be the only option. The testes contains germ cells at different stages of differentiation, including spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids, and spermatozoa, among which differences in cryoresistance might be expected. The present work compares the viability and DNA integrity of 'rounded' cells, and of elongated spermatids and spermatozoa, from the dog and wild boar, following the cryopreservation of testicular tissue by slow freezing or vitrification. Cell viability was analyzed by PI/SYBR14 staining, and DNA integrity via the TUNEL technique. For wild boar, no significant differences were seen between the two methods with respect to the percentage of viable cells, nor in the percentage of cells with DNA damage. In the dog, the percentage of viable rounded germ cells (65.0 ± 2.4%) was higher (P < 0.05) after vitrification than after slow freezing (45.1 ± 6.7%). No difference was found between the two methods in terms of the viability of elongated cells. For rounded cells, the percentage of intact DNA was greater (P < 0.05) after vitrification (90.5 ± 2.1%) than after slow freezing (42.6 ± 11.0%), while for elongated spermatids and spermatozoa it was higher (P < 0.05) after slow freezing (66.9 ± 6.1%) than after vitrification (50.7 ± 4.5%). Thus, the response to cryopreservation is cell type-, cryopreservation type-, and species-dependent. Vitrification would appear to be the most appropriate method for preserving dog testicular tissue given the associated high cell viability and low degree of DNA fragmentation, while in wild boar, either method might be used.

Comparative study of esterase activities in different tissues of marine fish species Trachurus trachurus, Merluccius merluccius and Trisopterus luscus.

Pesticides are one of the most frequently anthropogenic xenobiotics detected in water. Among these, the organophosphorus pesticides (OPs) are very widely used in agriculture due to their broad spectrum of activity and their low price, but they also have high potent effects as neurotoxic compounds in non-target organisms. The aim of this study was to evaluate biomarkers acetylcholinesterase (AChE), butyrylcholinesterase (BChE), propionylcholinesterase (PChE) and carboxylesterase (CbE) in the representative Atlantic fish species Trachurus trachurus, Merluccius merluccius and Trisopterus luscus from "Rías Gallegas", a traditional Spanish fishing area. These esterase activities were evaluated in the brain, muscle and liver to determine the most adequate tissue to measure such enzymatic activities. The sensitivity of AChE and CbE activities from different tissues the widely used organophosphorus insecticide chlorpyrifos (CP), and its toxic metabolite (CP-oxon) was also tested. AChE activity was predominant in all tissues of the analysed species (particularly in brain constituting from 78.33%, 89.83% and 88.43% of total ChEs in Trachurus trachurus, Merluccius merluccius and Trisopterus luscus, respectively). Under in vitro exposure, esterases were shown to be highly sensitive to CP and especially to CP-oxon. Moreover, a similar effect observed on AChE and CbE activities could suggest that CbE activity might contribute efficiently against the toxic effects of CP, especially in muscle and the liver. The presence of BChE, PChE and upper CbE activities in muscle and the liver and their OP-sensibilities can be used to study their function in the pesticide biochemical detoxification pathways with a prominent role as a safeguarding mechanism against pesticide toxicity.

Effect of long-term administration of cross-sex hormone therapy on serum and urinary uric acid in transsexual persons.

BACKGROUND: Transsexual persons afford a very suitable model to study the effect of sex steroids on uric acid metabolism. DESIGN: This was a prospective study to evaluate the uric acid levels and fractional excretion of uric acid (FEUA) in a cohort of 69 healthy transsexual persons, 22 male-to-female transsexuals (MFTs) and 47 female-to-male transsexuals (FMTs). The subjects were studied at baseline and 1 and 2 yr after starting cross-sex hormone treatment. RESULTS: The baseline levels of uric acid were higher in the MFT group. Compared with baseline, uric acid levels had fallen significantly after 1 yr of hormone therapy in the MFT group and had risen significantly in the FMT group. The baseline FEUA was greater in the FMT group. After 2 yr of cross-sex hormone therapy, the FEUA had increased in MFTs (P = 0.001) and fallen in FMTs (P = 0.004). In MFTs, the levels of uric acid at 2 yr were lower in those who had received higher doses of estrogens (P = 0.03), and the FEUA was higher (P = 0.04). The FEUA at 2 yr was associated with both the estrogen dose (P = 0.02) and the serum levels of estradiol-17beta (P =0.03). In MFTs, a correlation was found after 2 yr of therapy between the homeostasis model assessment of insulin resistance and the serum uric acid (r = 0.59; P = 0.01). CONCLUSIONS: Serum levels of uric acid and the FEUA are altered in transsexuals as a result of cross-sex hormone therapy. The results concerning the MFT group support the hypothesis that the lower levels of uric acid in women are due to estrogen-induced increases in FEUA.

Incidence of type 2 diabetes in southern Spain (Pizarra Study).

BACKGROUND: Few European studies have used an oral glucose tolerance test (OGTT) to examine the incidence of type 2 diabetes. We determined the incidence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and type 2 diabetes in a population from southern Spain. MATERIAL AND METHODS: A population-based cohort study was undertaken in Pizarra, Spain. Baseline data were recorded on age, sex, weight, height, waist and hip circumferences, and diabetes status for 1051 persons, of whom 910 were free of type 2 diabetes (at-risk sample). Of these, 714 completed the 6-year follow-up study. Body mass index, waist-to-hip ratio and weight increase since baseline were calculated. The homeostasis model assessment equations were used to estimate the indices of insulin resistance and beta-cell function. Each person received an OGTT at baseline and after 6 years. RESULTS: Type 2 diabetes developed in 81 people for a total of 4253 person-years, representing an incidence of 19.1 cases per 1000 person-years (95% confidence interval, 15.3-23.6). Age and the presence of obesity, central obesity and carbohydrate metabolism disorders [IFG (cut off = 100 mg dL(-1), capillary blood glucose level), IGT or both] at baseline were significant markers for the onset of type 2 diabetes during follow-up. After adjusting for these variables, multivariate analysis showed weight increase, waist-to-hip ratio and the indices of insulin resistance and beta-cell function were significantly associated with the risk for type 2 diabetes. CONCLUSIONS: The incidence of type 2 diabetes in a population from southern Spain is high. It is probably associated with the high prevalence of obesity and weight increase in this population.

Different effect of laparoscopic Roux-en-Y gastric bypass and open biliopancreatic diversion of Scopinaro on serum PYY and ghrelin levels.

BACKGROUND: The impact of bariatric surgery on levels of peptide YY (PYY) and ghrelin is still under discussion. We undertook a simultaneous evaluation of the serum changes in PYY and ghrelin depending on the specific type of bariatric surgery. METHODS: Total PYY and ghrelin were analyzed in 29 healthy persons and in morbidly obese persons undergoing open biliopancreatic diversion (BPD) of Scopinaro (n = 38) or laparoscopic Roux-en-Y gastric bypass (RYGB; n = 13). RESULTS: RYGB resulted in a significantly greater loss of weight and body mass index than BPD. Both RYGB and BPD were associated with a significant increase in PYY, significantly greater for BDP (p = 0.001). Ghrelin rose significantly after RYGB (p = 0.022) but not after BPD. After surgery, PYY correlated positively with weight (r = 0.416, p = 0.009). Ghrelin did not correlate significantly with any of the variables studied. Analysis of variance showed that only the type of surgery contributed significantly to explain the variances in the PYY (p = 0.002) and ghrelin (p = 0.018). CONCLUSIONS: BPD results in a greater increase in PYY and a lower weight loss than RYGB. However, only RYGB was associated with a significant increase in ghrelin. The differing weight loss according to the type of bariatric surgery does not seem to be explained by changes arising in PYY and ghrelin.

No effect of different bariatric surgery procedures on LINE-1 DNA methylation in diabetic and nondiabetic morbidly obese patients.

BACKGROUND: Bariatric surgery (BS) is proposed as a highly effective therapy for reducing weight and improving obesity-related co-morbidities. The molecular mechanisms involved in the metabolic improvement after BS are not completely resolved. Epigenetic modifications could have an important role. OBJECTIVE: The aim of this study was to evaluate the effect of different BS procedures (Roux-en-Y gastric bypass and laparoscopic sleeve gastrectomy) on global DNA methylation (long interspersed nucleotide element 1 [LINE-1]) in a group of nondiabetic and diabetic severely obese patients. SETTING: University hospital, Spain. METHODS: This study included 60 patients (30 nondiabetic and 30 diabetic severely obese patients) undergoing BS: 31 patients underwent Roux-en-Y gastric bypass and 29 underwent laparoscopic sleeve gastrectomy. Before and 6 months post-BS, anthropometric data, blood pressure, and metabolic parameters were determined. LINE-1 DNA methylation was quantified by pyrosequencing. We used the methylation levels of tumor necrosis factor-α as a control gene promoter. RESULTS: There were no differences between LINE-1 methylation levels at baseline and at 6 months after surgery (66.3±1.6 versus 66.2±2.06). Likewise, there was no statistically significant difference on LINE-1 methylation levels when we stratified according to metabolic status (diabetic versus nondiabetic), nor was there regarding the BS procedure. A strong correlation was shown between LINE-1 methylation levels and weight at baseline both in diabetic and nondiabetic obese patients (r = .486; P<.001). Tumor necrosis factor-α methylation levels increased significantly after BS in the group of diabetic obese patients. CONCLUSION: After BS, global LINE-1 methylation is not modified in the short term. More studies are required to determine if LINE-1 is a stable epigenetic marker, or, on the contrary, if it is susceptible to modification by external factors such as changes in lifestyle or a surgical intervention.

Immature and mature sperm morphometry in fresh and frozen-thawed falcon ejaculates.

Sperm morphometry is one characteristic which may be useful in prediction of fertility and sperm freezability in a species. Knowledge of the sperm characteristics of the ejaculate and the morphometric descriptors is necessary to effectively develop sperm cryopreservation. The aim of the current study was to provide a general description of the sperm from two falcon species (Peregrine falcon Falco peregrinus peregrinus/brookei and Gyrfalcon Falco rusticolus) including immature sperm, sperm head morphometric descriptors, and the existence of mature sperm subpopulations. Semen samples were collected by massage and voluntary false copulation and diluted with Lake and Ravie medium. Smears were prepared of the diluted samples, stained with Hemacolor®, and subjected to: 1) morphological analysis (bright field optical microscopy), and 2) computerised morphometric analysis; each sperm head was measured for length, width, area and perimeter. In addition, in the Gyrfalcon, pooled semen was frozen in pellets using DMA as a cryoprotectant and the analyses repeated after thawing. The mean percentage of immature sperm (spermatocytes and spermatids) was similarly high in all species/subspecies: Brookei Peregrine falcon (F. p. brookei) 55.5%, European Peregrine falcon (F. p. peregrinus) 65.5% and Gyrfalcon 64.7%. Clustering analyses identified four subpopulations of mature spermatozoa with different morphometric characteristics (P < 0.001). The relative proportions of these subpopulations were similar in all three species. The mean values recorded for the morphometric variables of the four subpopulations were, however, lower (P < 0.001) in the thawed Gyrfalcon samples than in fresh samples. The results support the idea of pleiomorphy as a characteristic of raptor mature sperm. This finding, plus that of the existence of four sperm subpopulations with different morphometric characteristics, may be important in the future development of cryopreservation protocols for falcon sperm.

Successful chilling of red-legged partridge (Alectoris rufa) sperm for use in artificial insemination.

The fertilizing capacity of pure, fresh avian semen may disappear in just half an hour, hindering its successful use in artificial insemination (AI) projects. Longer storage requires the use of infra-physiological temperatures and of semen diluents that help preserve the spermatozoa but that do not interfere with their fertilizing capacity. This study examines the effect on sperm quality of storing red-legged partridge sperm for 3 h at 5°C with 2 different semen extenders: 1) a medium referred to as L&R-84, composed of sodium glutamate, glucose, magnesium acetate, potassium acetate, and polyvinylpyrrolidone, and 2) Lake 7.1 medium, composed of sodium glutamate, glucose, magnesium acetate, potassium citrate, and N,N-Bis(2-hydroxyethyl)taurine (BES). Extending with L&R-84 returned better curvilinear velocity (P < 0.01), straight-line velocity (P < 0.01), average path velocity (P < 0.01), linearity (P < 0.05), straightness (P < 0.05), and wobble (P < 0.05) values, while extending with the Lake 7.1 medium was associated with higher percentages (P < 0.001) of motile sperm. The fertility rate was higher (P < 0.05) when birds were inseminated with L&R-84-extended sperm than with Lake 7.1-extended sperm. The mean number of penetrations of perivitelline layer samples (taken from above the germinal disc) was also higher for the L&R-84-extended sperm (P < 0.05). These results show L&R-84 can be recommended as an extender for red-legged partridge semen to be stored for at least 3 h at 5°C.

Dietary fatty acids and insulin secretion: a population-based study.

OBJECTIVE: Few epidemiological studies have examined the relationship of dietary fatty acids, especially MUFA, with the interrelation between insulin secretion and insulin resistance. We assessed the relation of dietary fatty acids with insulin secretion in a free-living population. DESIGN AND SETTING: This cross-sectional, population-based study was undertaken in Pizarra, a small town in Spain. SUBJECTS AND METHODS: Anthropometrical data were collected for 1226 persons selected randomly from the municipal census, 538 of whom (randomly chosen) were given a prospective, quantitative, 7-day nutritional questionnaire. The fatty acid composition of the serum phospholipids was used as a biological marker of the type of fat consumed. Beta-cell function (betaCFI) and insulin-resistance index (IRI) were estimated by the Homeostasis Model Assessment. RESULTS: To determine which factors influence the variability of the betaCFI, we analyzed the variance of the betaCFI according to sex, the presence of carbohydrate metabolism disorders and the different components of the diet, adjusting the models for age, body mass index (BMI) and IRI. The dietary MUFA and polyunsaturated fatty acids (PUFA) contributed to the variability of the betaCFI, whereas only the proportion of serum phospholipid MUFA, but neither the saturated fatty acids nor the PUFA accounted for part of the variability of the betaCFI in a multiple regression analysis. CONCLUSION: The results of this population-based study corroborate the results of other clinical and experimental studies suggesting a favorable relationship of MUFA with beta-cell insulin secretion. SPONSORSHIP: Fondo de Investigación Sanitaria, Junta de Andalucía and the Asociación Maimónides.

The apolipoprotein E genotype predicts postprandial hypertriglyceridemia in patients with the metabolic syndrome.

Apolipoprotein E (apo E) is a constituent molecule of the triglyceride-rich lipoproteins and participates in their clearance. Polymorphisms in the apo E gene are associated with increased fasting and postprandial levels of triglycerides. We studied 66 patients with the metabolic syndrome, none of whom had diabetes. Details were recorded for cholesterol, triglycerides, apo AI, apo B, insulin, homeostasis model assessment of insulin resistance, homeostasis model assessment of insulin secretion, uric acid, 24-h uric acid urinary excretion, high-density lipoprotein cholesterol, waist to hip ratio, body mass index, and age. The patients were given a 60-g fat overload (Supracal), and measurements were made at 4 h of cholesterol, triglycerides, high-density lipoprotein cholesterol, apo AI, and apo B. Patients who did not have the E3/3 genotype had an odds ratio of postprandial hypertriglyceridemia of 6.2 (confidence interval, 1.41-16.08; P = 0.01) and an odds ratio of hyperuricemia compared with the E3/3-positive patients of 7.5 (confidence interval, 1.04-39.31; P = 0.02). This study shows that patients with the metabolic syndrome who do not have the E3/3 genotype have a greater risk of hyperuricemia and postprandial hypertriglyceridemia after a fat overload.

Hypovitaminosis D and incidence of obesity: a prospective study.

The aim of this study was to assess the relationship between obesity and vitamin D status cross-sectionally, the relationship between obesity and the incidence of hypovitaminosis D prospectively and inversely the relationship between vitamin D status and incidence of obesity in a population-based cohort study in Spain. At baseline (1996-1998), 1226 subjects were evaluated and follow-up assessments were performed in 2002-2004 and 2005-2007, participants undergoing an interview and clinical examination with an oral glucose tolerance test. At the second visit, 25-hydroxyvitamin D and intact parathyroid hormone concentrations were also measured. Prevalence of obesity at the three visits was 28.1, 36.2 and 39.5%, respectively. The prevalence of vitamin D deficiency (25-hydroxyvitamin D ≤ 20 ng/ml (≤ 50 nmol/l)) was 34.7%. Neither obesity at baseline (OR=0.98, 95% CI: 0.69-1.40, P=0.93) nor the development of obesity between baseline and the second evaluation (OR=0.80, 95% CI: 0.48-1.33, P=0.39) were significantly associated with vitamin D status. In subjects who were non-obese (BMI <30 kg/m²) at the second evaluation, 25-hydroxyvitamin D values ≤ 17 ng/ml (≤ 42.5 nmol/l) were significantly associated with an increased risk of developing obesity in the next 4 years (OR=2.35, 95% CI: 1.03-5.4, P=0.040 after diverse adjustments). We conclude that vitamin D deficiency is associated with an increased risk of developing obesity.

Vitamin D deficiency in Spain: a population-based cohort study.

BACKGROUND: Vitamin D deficiency is common worldwide. No homogenous reference values have yet been established and no studies of values have been conducted in Spain involving a large number of participants. OBJECTIVE: To study the population concentrations of vitamin D in a representative sample of the Spanish population. SUBJECTS/METHODS: The study involved two cohorts from Spain, the Asturias study and the Pizarra study, which are two prospective, population-based studies involving 2260 participants. In 1262 subjects (age: 20-83 years) we studied 25-hydroxyvitamin D, intact parathyroid hormone (iPTH), calcium, phosphorus and creatinine. RESULTS: The median population values of 25-hydroxyvitamin D and iPTH were 22.46 ng/ml and 42.29 pg/ml, respectively. The values of 25-hydroxyvitamin D were significantly higher in summer and correlated with age (ß = -0.05 ± 0.01, P < 0.0001), creatinine (ß = 6.42 ± 1.17, P < 0.0001) and iPTH (-0.07 ± 0.01, P < 0.0001), but not with calcium, phosphorus or sex. The increase in iPTH with age was seen whatever the values of 25-hydroxyvitamin D, and was greater in the older persons. The concentration of iPTH rose continuously with effect from 25-hydroxyvitamin D values below ≈30 ng/ml. Values above ≈35 ng/ml were associated with a significantly lower concentration of iPTH. CONCLUSIONS: One-third (33.9%) of the Spanish population may be at risk for Vitamin D deficiency. The 25-hydroxyvitamin D values above 30 ng/ml can safely discard 'hyper PTH'. The increase in iPTH concentration is greater in older persons for similar values of 25-hydroxyvitamin D.

Incidence of obesity is lower in persons who consume olive oil.

We undertook a population-based cohort study in Pizarra (Spain). Anthropometric and nutritional variables were recorded for 613 persons. The type of fat used was determined by measurement of the fatty acids contained in cooking oil. Serum fatty acid was used as a biological marker of the type of fat consumed. Obesity incidence in persons who were not obese at baseline was greater in those who consumed sunflower oil (Group 1: 41.5 (95% CI, 25.4-67.8) cases per 1000 person-years) than in those who consumed olive oil or a mixture of oils (Group 2: 17.3 (95% CI, 11.6-25.8) cases per 1000 person-years). The risk of developing obesity over 6 years, adjusted for age, sex, physical activity, smoking, instruction level, energy intake and baseline BMI, was 2.3 (95% CI, 1.06-5.02) in group 1 compared with that in group 2. The increase in the prevalence of obesity in the free-living population is associated with the type of fatty acids in the diet.

The -30G>A polymorphism of the glucokinase gene promoter is associated with obesity in a population from southern Spain.

The aim of this study was to test the hypothesis of an association between the -30G>A polymorphism of the promoter of the glucokinase gene and the prevalence and incidence of obesity. We studied the -30G>A polymorphism of the glucokinase gene promoter in 981 persons, of whom 866 were seen again 6 years later. All the persons underwent an oral glucose-tolerance test and the BMI (weight/height(2)) was recorded. The -30G>A polymorphism of the glucokinase gene promoter was studied using RFLP-PCR. At the initial study, the probability of having a BMI > or =25 in carriers of the A allele was significantly lower than expected by chance (odds ratio (OR) = 0.63; 95% confidence interval (CI) = 0.456-0.885). In those persons with a BMI > or =30 at the first study, the probability at 6 years of losing weight (reaching a BMI < 30) was greater in carriers of the A allele (OR = 0.22; 95% CI = 0.087-0.576). The increase in weight over these 6 years, taken as a continuous variable, was significantly less only in those persons who were originally obese (P = 0.018). In conclusion, in a population from southern Spain, carriers of the A allele of the -30G>A polymorphism in the promoter of the glucokinase gene had a lower risk for obesity and the likelihood of losing weight was greater in those obese persons who had the A allele (GA or AA).