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S Gaztambide

Publications and source records attributed to S Gaztambide.

13 recordsLinked to original sources
PubMed2006

Conserved extended haplotypes discriminate HLA-DR3-homozygous Basque patients with type 1 diabetes mellitus and celiac disease.

The major susceptibility locus for type 1 diabetes mellitus (T1D) maps to the human lymphocyte antigen (HLA) class II region in the major histocompatibility complex on chromosome 6p21. In southern European populations, like the Basques, the greatest risk to T1D is associated with DR3 homo- and heterozygosity and is comparable to that of DR3/DR4, the highest risk genotype in northern European populations. Celiac disease (CD) is another DR3-associated autoimmune disorder showing certain overlap with T1D that has been explained by the involvement of common genetic determinants, a situation more frequent in DR3-rich populations, like the Basques. As both T1D- and CD-associated HLA alleles are part of conserved extended haplotypes (CEH), we compared DR3-homozygous T1D and CD patients to determine whether CEHs were equally distributed between both disorders or there was a differential contribution of different haplotypes. We observed a very pronounced distribution bias (P<10(-5)) of the two major DR3 CEHs, with DR3-B18 predominating in T1D and DR3-B8 in CD. Additionally, high-density single nucleotide polymorphism (SNP) analysis of the complete CEH [A*30-B*18-MICA*4-F1C30-DRB1*0301-DQB1*0201-DPB1*0202] revealed extraordinary conservation throughout the 4.9 Mbp analyzed supporting the existence of additional diabetogenic variants (other than HLA-DRB1*0301-DQB1*0201), conserved within the DR3-B18 CEH (but not in other DR3 haplotypes) that could explain its enhanced diabetogenicity.

Celiac Disease↗
PubMed2003

Nonadherence and osteoporosis treatment preferences of older women: a qualitative study.

BACKGROUND: Physicians must have an understanding of patients' medication beliefs in order to enhance medication adherence. To increase understanding, this study examined how beliefs about medication and four osteoporosis treatments influenced treatment selection and adherence. METHODS: Six focus groups, three with 28 African Americans and one with 11 non-Hispanic white women, were conducted in English. Two groups with 16 Hispanics were conducted in Spanish. The convenience sample was recruited from senior centers and housing in lower socioeconomic geographic areas. The average age was 74.8 +/- 1.1 years. RESULTS: Adherence was associated with recognition of the serious consequences of nonadherence, realization of the beneficial effects, and the belief that medicines are not harmful. Doubts about physicians' competence to prescribe appropriate drugs were also revealed. Women who thought they were unlikely to fracture or perceived fracture outcomes as not severe chose no treatment. If they identified a need, they weighed benefits against the attendant risks to find the best alternative among the affordable options. Price considerations eliminated raloxifene and alendronate. Consideration of side effects eliminated estrogen and raloxifene. Calcium was viewed as a low-cost, low-risk alternative. Those who could afford alendronate and who viewed its side effects as preventable preferred it. Benefit and risk assessments may have been biased by fear of cancer and thromboembolic events. CONCLUSIONS: Women's beliefs about necessity of treatment, medication safety, cost of treatment, and treatment goals appear critical to osteoporosis treatment selection and adherence.

Black or African American↗
PubMed2002

Acromegaly Quality of Life Questionnaire (ACROQOL) a new health-related quality of life questionnaire for patients with acromegaly: development and psychometric properties.

OBJECTIVE: To develop a disease-specific questionnaire suitable to measure health-related quality of life (HRQOL) in acromegaly (ACROQOL). DESIGN, PATIENTS AND MEASUREMENTS: For the development of the ACROQOL questionnaire different sources of information were used: First, a literature search was performed to identify relevant papers describing the impact of acromegaly in HRQOL. Second, 10 endocrinologists identified the main domains of impact on HRQOL in patients with acromegaly. Third, 10 in-depth, semistructured interviews were conducted in acromegalic patients to identify domains and items related to the self-perceived impact of acromegaly in patients' life. Qualitative analyses of the information were performed identifying domains and items to be included in the questionnaire. Those items considered ambiguous, complicated to read, double-barrelled, with jargon terms, too long, or negatively worded were excluded. Each remaining item was subsequently rated by the same panel of endocrinologists and experts in HRQOL evaluation, and assessed according to clarity of wording, frequency of occurrence and importance among patients with acromegaly. Analysis of internal consistency of the questionnaire was evaluated with a Cronbach's Alpha. A preliminary questionnaire was administered to 72 patients with acromegaly. Rasch analysis (dichotomous logistic response model) of the answers given by these patients allowed parameter estimates and model data fit indices to be computed and misfitting items deleted. Frequency of occurrence and degree of agreement with the statements were selected as response choices in a 5-point Likert type scale. RESULTS: The following domains related to HRQOL in acromegaly were identified: physical and psychological functions, social, daily activities, symptoms, cognition, general health perception, sleep, sexual function, pain, energy and body image. An initial set of 204 expressions were identified from the initial transcripts of the patient interviews. After elimination of ambiguous or unclear expressions, 142 items remained drafted in question form. From the quantitative analysis of the item rank position within each of the three areas of clarity, frequency and importance, the 38-item questionnaire was produced, with satisfactory internal consistency (Cronbach's Alpha 0.94). Rasch analysis produced a further reduction to the final 22-item questionnaire (Cronbach's Alpha 0.91) containing two scales that evaluate physical (eight questions) and psychological aspects related to appearance and personal relations (seven items each). The evaluation of the item parameters confirmed the construct validity of the new instrument. The substantial reliability of the questionnaire suggested the sample was well targeted by the questionnaire. The initial Spanish version was translated into English and presented to five English-speaking Australian patients with acromegaly to assess and correct for comprehension, clarity, cultural relevance and suitable wording. CONCLUSIONS: We present the ACROQOL questionnaire, developed and preliminarily validated to specifically assess HRQOL in patients with acromegaly.

Acromegaly↗
PubMed2002

Giant pituitary adenomas: clinical characteristics and surgical results.

Although most pituitary neoplasms are benign, some grow rapidly, spreading to extrasellar tissues. Definition of these 'giant' pituitary adenomas (PAs) is not clear. In order to clarify this question, we studied all pituitary macroadenomas operated in our hospital during the last 20 years, differentiating those with diameter > or = 3 cm (n = 43) and attempting to identify their typical features and prognosis. The reason for consultation was local in 58.3% of giant PAs, hormonal in 22.9% and tumour recurrence in 16.7%. Surgery was performed via a trans-sphenoidal approach in 92.5% of cases and succeeded in completely removing the tumour in only 27% of cases. In conclusion, we found that giant PAs are not a special type but the extreme case in the gradient of invasiveness of tumours of adenohypophyseal origin. They are characterized by a higher frequency of neuro-ophthalmological symptoms and hormonal deficits, and poorer response to surgical treatment.

Adenoma↗
PubMed2000

[10-year prospective study on the incidence and risk factors for type 2 diabetes mellitus].

BACKGROUND: The aims of this study were to determine the incidence of diabetes mellitus type 2 and to define the associated risk factors. PATIENTS AND METHOD: A 10-year prospective study was done over 584 people identified by screening of the Lejona (Vizcaya, Spain) adult population in 1985. Data on age, sex, body mass index, family history of diabetes mellitus and blood pressure were collected. Also an oral glucose tolerance test was done following the criteria recommended by the WHO. RESULTS: Age-adjusted cumulative incidence per year was 8 per 1,000 persons. In a multivariate logistic regression analysis, impaired glucose tolerance was the major predictor of worsening to diabetes (relative risk 4.17; 95% confidence interval 1.80-9.63). Age and sex were also statistically significant predictors (p < 0.05), and family history of diabetes was almost significant (p = 0.057). Body mass index was not an independent and significant risk factor in this study. However, the rise in body mass index was larger in those who progressed to diabetes mellitus type 2 than in those who did not. CONCLUSIONS: The incidence of diabetes mellitus type 2 found in Lejona was similar to that reported in other european countries. Subjects having impaired glucose tolerance as well as those with elevated blood glucose levels are at higher risk of worsening to diabetes mellitus type 2. Body mass index seems to play a precipitating role in the progression to diabetes mellitus type 2.

Adult↗
PubMed2000

Comparison of octreotide acetate LAR and lanreotide SR in patients with acromegaly.

BACKGROUND AND OBJECTIVE: The most effective option for the medical treatment of patients with acromegaly is the use of somatostatin analogues. Long-acting depot formulations for intramuscular injection of two somatostatin analogues have recently become available: octreotide acetate LAR (Sandostatin LAR, Novartis Pharma AG) and lanreotide SR (Somatuline, Ipsen Biotech). We wished to compare efficacy of octreotide LAR and lanreotide SR in acromegalic patients. PATIENTS AND METHODS: A group of 125 patients with acromegaly (67 females; mean age, 47 years; 59 patients had previous pituitary irradiation) from 26 medical centres in France, Spain and Germany were studied. Before the study, all patients had been treated with intramuscular injections of lanreotide SR (mean duration, 26 months) at a dose of 30 mg which was injected every 10 days in 64 and every 14 days in 61 patients, respectively. All patients were switched from lanreotide SR to intramuscular injections of 20 mg of octreotide LAR once monthly for three months. In order to obtain efficacy and safety data of lanreotide SR under study conditions, it was decided to randomly assign at day 1, in a 3 : 1 ratio, the time point of the treatment switch; 27 of the patients were randomly assigned to continue the lanreotide SR treatment for the first 3 months of the study (group A); they were on octreotide LAR 20 mg from month 4-6. The other 98 patients were assigned to be switched to treatment with octreotide LAR 20 mg at day 1 (group B). In group B patients, octreotide LAR treatment was continued until month 6, with an adjustment of the dose based on GH levels obtained at month 3. RESULTS: The mean GH concentration decreased from 9.6 +/- 1.3 mU/l at the last evaluation on lanreotide SR to 6.8 +/- 1.0 mU/l after three injections of octreotide LAR (P < 0.001). The percentages of patients with mean GH values < or = 6.5 mU/l (2.5 microg/l) and < or = 2.6 mU/l (1.0 microg/l) at the last evaluation on lanreotide SR were 54% and 14%, and these values increased after 3 months treatment with octreotide LAR to 68% and 35% (P < 0.001), respectively. IGF-I levels were normal in 48% at the last evaluation on lanreotide SR and in 65% after 3 months on octreotide LAR (P < 0.001). Patients with pre-study pituitary irradiation had lower mean GH and IGF-I concentrations. But the effects of the treatment change did not differ between the irradiated and the nonirradiated patients. In general both drugs were well tolerated. CONCLUSION: Octreotide LAR 20 mg administered once monthly was more effective than lanreotide SR 30 mg administered 2 or 3 times monthly in reducing GH and IGF-I in patients with acromegaly.

Acromegaly↗
PubMed1999

Short- and long-term effect of a long-acting somatostatin analogue, lanreotide (SR-L) on metastatic gastrinoma.

Medical treatment is the elective therapy for patients with gastrinoma when the tumor is not found at surgery or is unresectable or when there is a metastatic disease. H2-blockers and omeprazol are able to control gastric acid secretion and, in addition, somatostatin analogues decrease gastrin levels. A new long-acting and slow release formulation of a somatostatin analogue (lanreotide, SR-L) has been developed. We treated two patients suffering from gastrinoma, total gastrectomy and hepatic metastases with 30 mg intramuscular injections of SR-L every 15 and 10 days, respectively, for a seven-month period. After the treatment, gastrin levels decreased from 35,494 and 15,086 ng/l to 3,211 and 167 ng/l (92 and 98% below pre-treatment levels) in case 1 and 2 respectively, with a relief of symptoms and no side effects.

Adult↗
PubMed1998

Identification of a novel nonsense mutation and a missense substitution in the vasopressin-neurophysin II gene in two Spanish kindreds with familial neurohypophyseal diabetes insipidus.

Familial neurohypophyseal diabetes insipidus (FNDI) is an autosomal dominant disease caused by deficiency in the antidiuretic hormone arginine vasopressin (AVP) encoded by the AVP-neurophysin II (AVP-NPII) gene on chromosome 20p13. In this study, we analyzed two families with FNDI using direct automated fluorescent, solid phase, single-stranded DNA sequencing of PCR-amplified AVP-NPII DNA. In one of the families, affected individuals presented a novel nonsense mutation in exon 3 of the gene, consisting in a G to T transition at nucleotide 2101, which produces a stop signal in codon 82 (Glu) of NPII. The premature termination eliminates part of the C-terminal domain of NPII, including a cysteine residue in position 85, which could be involved in the correct folding of the prohormone. In the second family, a G279A substitution at position -1 of the signal peptide was observed in all affected individuals. This missense mutation, which replaces Ala with Thr, is frequent among FNDI patients and is thought to reduce the efficiency of cleavage by signal peptidases.

Adolescent↗
PubMed1993

Acromegaly: an epidemiological study.

Although morbility and mortality in acromegaly are higher than in the general population, there have been very few previous epidemiological studies. This study tries to answer "why". Seventy-four patients affected by acromegaly in Vizcaya (Spain) between 1970 and 1989 were considered for an epidemiological study. The prevalence of known cases at the end of 1989 was 60 per million inhabitants. The average incidence of newly diagnosed cases was 3.1 per million people per year. Unexpectedly, acromegaly was more frequent in women (n = 48) than in men (n = 26), with a ratio of 1.8:1. Mean age at diagnosis was significantly higher in women (46.1 +/- 2.2 yr) than in men (39.5 +/- 2.2 yr) (p < 0.05) There was a positive correlation between age at diagnosis and the estimated duration of the disease (r = 0.56, p < 0.05) and a negative one between age and basal GH serum levels (r = -0.52 p < 0.002). The age at diagnosis was significantly higher in patients with invasive tumors (grade III and IV) than in those with enclosed tumors (grade I and II) (47.7 +/- 1.8 vs 40.1 +/- 3.3 p < 0.05). In general, mortality was higher than the expected for the control population (standardized mortality ratio, SMR = 3.2, 95% confidence interval. Cl = 1.55-5.93). However, mortality was higher in men (SMR = 7, 95% Cl = 2.81-14.4) but not in women (SMR = 1.4 95% Cl = 0.29-4.17).(ABSTRACT TRUNCATED AT 250 WORDS)

Acromegaly↗
PubMed1990

Role of cholinergic muscarinic pathways on the free fatty acid inhibition of GH responses to GHRH in normal men.

In order to explore the mechanisms by which free fatty acids (FFA) inhibit GH secretion, we studied the effect of the acetylcholinesterase inhibitor pyridostigmine (120 mg p.o.) on the FFA blockade of GH responses to the administration of GHRH (100 micrograms i.v.) in seven normal subjects. GHRH-induced GH secretion was significantly reduced following elevation of circulating FFA levels by lipid-heparin infusion and significantly potentiated by previous pyridostigmine treatment. Peak GH levels following combined administration of pyridostigmine plus lipid-heparin plus GHRH were significantly higher (P less than 0.01) than after GHRH alone and significantly lower than after pyridostigmine plus GHRH (P less than 0.01). In conclusion, central cholinergic activation by pyridostigmine, with the presumed reduction in somatostatin discharge, reversed the blocking effect of FFA on GHRH-stimulated GH release. Conversely, FFA were able to reduce even a maximal GH stimulation by pyridostigmine plus GHRH.

Adult↗
PubMedDate not supplied

Course and prognosis of 132 patients with diabetic non ketotic hyperosmolar state.

One hundred and thirty two episodes of diabetic non ketotic hyperosmolar states were studied after a prospective schedule of treatment was designed. The admission data, the prognostic factors and their outcome were analyzed. Initial high osmolarity, urea and sodium plasma levels and low plasma pH were related to the admission level of consciousness (p < 0.01). High glucose, osmolarity, urea and sodium plasma levels at entry were related to the admission level of dehydration (p < 0.01). In multivariate regression analysis, osmolarity was the most influential variable in both the level of consciousness and the admission level of dehydration (p < 0.0001). Twenty two patients died (16.9%). Septic shock was the most frequent cause of death (31%) and mortality was higher in patients with cardiovascular disease (acute myocardial infarction or stroke) as the precipitating factor for diabetic hyperosmolar state (p < 0.002). Older age, low blood pressure, low sodium, pH and bicarbonate plasma levels, and high urea plasma levels were related to mortality (p < 0.01). In multiple regression analysis, urea was the most influential mortality risk factor (p < 0.0118). Non survivors received higher doses of insulin than survivors (p < 0.01). All these data suggest that it is not the hyperosmolarity itself, but the hemodynamical state of the patients, which is the most influential factor on the prognosis of a diabetic hyperosmolar state.

Age Factors↗