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J A Amado

Publications and source records attributed to J A Amado.

At least 19 recordsLinked to original sources
PubMed2006

Blood-soluble Fas levels are increased in type 2 diabetic patients with peripheral vascular disease.

AIM: To investigate the possible utility of plasma sFas (soluble Fas) levels as a marker of peripheral vascular disease (PVD) in type 2 diabetic patients, and the relationship between classical cardiovascular risk factors and sFas levels in these patients. MATERIALS AND METHODS: sFas levels were measured in 57 type 2 diabetic patients with and 60 without PVD matched for age and sex. Diagnosis of PVD was established in presence of at least one of the following criteria: leg or foot amputation of vascular cause, lower-extremity arterial angioplasty or surgical by-pass, or ankle-braquial index (ABI) less than 1 in at least one side of the body. ELISA was used to measure sFas levels. RESULTS: None of the risk factors assessed total cholesterol, HDL cholesterol, triglycerides, CRP, ACE, fibrinogen, Lp(a) and homocysteine was significantly different between both groups of patients. However, patients with PVD had higher plasma sFas levels than the group without PVD (10.25+/-3.7 ng/ml VS. 8.86+/-2.6 ng/ml; p=0.02). Levels of sFas were 1.45 ng/ml (95% CI: 0.32-2.58; p=0.013) higher in PVD patients when adjusting by age, total, HDL and LDL cholesterol, triglycerides, homocysteine, CRP, ACE, arterial hypertension and tobacco smoking. Using multiple logistic regression sFas is a predictor of PVD, although not potent. CONCLUSION: Plasma sFas may be an independent marker of PVD in type 2 diabetes mellitus patients.

Aged↗
PubMed2006

Factors other than glucocorticoids are involved in the osteoblast activity decrease caused by tissue injury.

OBJECTIVE: Serum osteocalcin is a marker of bone formation. The concentration of osteocalcin is decreased with tissue injury. As glucocorticoids are known both to be increased in this situation and to diminish serum osteocalcin, we have hypothesized that they could be involved in this decrease. DESIGN AND PATIENTS: We compared osteocalcin levels in two groups of patients undergoing abdominal surgery, one receiving thiopental, and the other etomidate, a glucocorticoid synthesis blocker. For comparative reasons, another protein decreased by glucocorticoids (osteoprotegerin) was measured in patients anaesthetized with thiopental. MEASUREMENTS: Serum osteocalcin, cortisol and albumin were determined before and over the 24 h following surgery. Serum concentration of osteoprotegerin (OPG) and receptor activator of the nuclear factor kappaB ligand (RANKL) were also determined before and 24 h after surgery in a third group of nine patients who received thiopental for anaesthetic induction. RESULTS: Cortisol levels were increased in the thiopental group, whereas, as expected, were decreased in etomidate patients. However, serum osteocalcin concentration decreased in a similar way in both groups. Serum OPG and RANKL levels were within the normal range at baseline and did not significantly change after surgery. CONCLUSIONS: The decrease in serum osteocalcin induced by tissue injury is independent of the increase in cortisol secretion triggered by the latter. In addition, another pharmacologically proven effect of cortisol on bone metabolism, OPG inhibition, could not be demonstrated in the first 24 h following surgery, in spite of the physiological increase in endogenous cortisol secretion taking place in this period.

Abdomen↗
PubMed2005

Fasting plasma ghrelin levels increase progressively after biliopancreatic diversion: one-year follow-up.

BACKGROUND: The role of ghrelin in weight control after surgery is not clear. We examined plasma ghrelin and leptin levels in patients with morbid obesity undergoing biliopancreatic diversion (BPD) of Scopinaro. METHODS: 30 adult patients (27 females, 3 males), undergoing elective BPD were recruited from the Hospital Surgery Service. Fasting blood samples for biochemical determinations were drawn before surgery and 1, 3 and 12 months after BPD. Human plasma ghrelin was measured by RIA. RESULTS: During the study period, weight, BMI and serum leptin levels decreased significantly at all sample points compared to preoperative values. Ghrelin plasma levels increased during the study, with statistical significance at 3 months and 1 year after surgery compared with preoperative levels. While leptin changes correlated with changes in BMI, no correlation was found between ghrelin and leptin or BMI changes. CONCLUSION: Plasma ghrelin levels could be decreased in obese patients as a compensatory mechanism to their nutritional state, but our results do not support the postulated beneficial role of ghrelin in the 1-year weight loss after BPD. They rather suggest that weight loss somehow stimulates ghrelin secretion, even in the absence of part of the stomach.

Adult↗
PubMed2004

[Plasma leptin levels in patients with primary biliary cirrhosis and their relationship with degree of fibrosis].

OBJECTIVES: a) To analyze plasma leptin levels in patients with primary biliary cirrhosis (PBC) and b) to investigate the relationship between leptin levels and liver fibrosis stage in a cohort of patients with PBC. PATIENTS AND METHODS: Serum leptin levels were evaluated through radioimmunoassay in 30 patients with PBC (mean age: 37.2 +/- 11.0 years; range:19-75) and in 29 controls matched for age and weight. Venous blood obtained after a 12-hour fast was centrifuged in EDTA tubes. Weight, height and body mass index (BMI) were measured using standard methods. Hepatitis C virus RNA was determined using qualitative and quantitative polymerase chain reaction. In all patients liver biopsies were performed and the degree of fibrosis and extent of inflammatory infiltrate were evaluated. RESULTS: Plasma leptin levels in patients with PBC were lower than those obtained in control subjects (p<0.0001). No significant differences were found between the two groups in age, weight, height, BMI or body fat index. There was a clear increase in serum leptin levels according to histological stage of PBC (stage I: 2.1 ng/ml; stage II: 4.3 ng/ml; stage III: 5.3 ng/ml; stage IV: 12.1 ng/ml; p<0.01) CONCLUSIONS: The present study demonstrates the correlation between leptin and stage of liver fibrosis in a cohort of patients with PBC, providing further evidence of the involvement of leptin in the process of liver fibrosis.

Adult↗
PubMed2003

Autoantibodies against oxidized LDL and serum total antioxidant status in active cyclists and ex-cyclists.

There is an apparent paradox between the benefits of aerobic exercise and the potentially deleterious effects of increased free radicals and decreased circulating antioxidants generated during exercise. To assess the oxidative/antioxidative status in competitive cyclists and ex-cyclists, we measured two markers not well studied in these situations, serum total antioxidant status (TAS) and antibodies against oxidized LDL (AuAb-ox-LDL) in 18 competitive male cyclists, 10 ex-competitive cyclists and 14 healthy males. AuAb-ox-LDL was evaluated by enzyme immunoassay, and serum TAS concentration was analyzed by spectrophotometry. Ex-cyclists had serum TAS levels statistically higher than the control group and cyclists group (p = 0.001 and p < 0.001, respectively). Active sportsmen showed significantly less AuAb-ox-LDL than healthy sedentary males, while there was a non-significant trend in the ex-cyclists to have lower AuAb-ox-LDL than the corresponding control group. AuAb-ox-LDL levels were not statistically different between the groups of active and previously active sporting men. There was a positive correlation between TAS and LDL-cholesterol in active cyclists under heavy training. In the ex-cyclist group, there was a negative correlation between serum TAS and the time elapsed since they had ended the competition. Competitive cycling decreases AuAb-ox-LDL levels, suggesting that it may decrease ox-LDL levels. After ending physical training, antioxidative status remains increased for at least one year, but the effect on AuAb-ox-LDL levels is lost.

Adolescent↗
PubMed2002

Parathyroidectomy in dialysis patients.

Subtotal parathyroidectomy or total parathyroidectomy (PTx) with autotransplantation are surgical procedures considered while the patient is included on the waiting list for renal transplantation. Total PTx alone is based in the possibility that a fragment of tissue (nodular hyperplasia in particular) left in the same pathophysiological environment of long term dialysis would show the same behavior and reproduce in time the same clinicopathological picture. The persistence of uremia induces a continued growth stimulus developing residual hyperplasia and consequently a very high risk of recurrence. We performed total PTx alone in 15 uremic patients excluded for renal transplantation 10 patients with undetectable iPTH serum concentration and were followed up for 37 to 144 months. There was no evidence of clinical bone disease (bone pain or fractures). Bone mineral lumbar spine and hip density was measured at the end of follow-up. The z score data showed that all patients had a bone mass similar than that expected for their age. Bone biopsies performed in four patients showed a uniform picture of low turnover without aluminium staining. Calcification of small arteries (digital and arcade vessels in hands and feet) were evaluated pre and post total PTx alone in nine out of the 10 patients with undetectable PTH levels. The small vessel calcification was present in five patients at the moment of PTx. At the end of the long term follow-up only one patient showed progression. In conclusion, total PTx without autotransplantation is a very effective and adequate treatment for refractory severe hyperparathyroidism in patients excluded for renal transplantation. Aluminium related osteopathy post PTx is a risk to be controlled with aluminium "free" dialysis water and avoiding aluminium containing phosphate binders.

Calcitriol↗
PubMed2001

Venous endothelial function in postmenopausal women after six months of tibolone therapy.

STUDY OBJECTIVE: To test venous endothelial function in long-term climateric therapy with tibolone. DESIGN: Measurement of dorsal hand-vein diameter by venous occlusion plethysmography during infusion of norepinephrine (NE), bradykinin (BK), NG-monomethyl L-arginine (L-NMMA) and sodium nitroprusside (SNP). SETTING: Plethysmography and Menopause Units. University Hospital Valdecilla. Santander. Spain. PATIENTS: Eleven postmenopausal women having continuous treatment with oral tibolone (2.5 mg/day) for 6 months. INTERVENTIONS: Three plethysmography studies were made: at baseline, and at three and six months of treatment. MAIN OUTCOME MEASURES: Dorsal hand-vein diameter measured by venous occlusion plethysmography during infusion of NE, BK, L-NMMA and SNP. RESULTS: (a) Baseline study: maximum dilation with BK was 54.2+/-10.2%. (b) Three-month study: BK dilation of 71.5+/-11.9%, with a significant increase of 17.3% (P=0.019) compared with baseline. (c) Six-month study: BK dilation of 77.5+/-11.9%, with a significant increase 23.3% (P=0.002) compared with baseline. Maximal vasodilation was reached with SNP in the three studies and L-NMMA infusion has a similar vasoconstrictor response in the three studies. CONCLUSIONS: Long-term climateric therapy with tibolone improves vein endothelium-dependent vasodilation suggesting a positive impact of this drug on endothelial function.

Administration, Oral↗
PubMed2001

Assessment of cerebral perfusion and cerebrovascular reserve in insulin-dependent diabetic patients without central neurological symptoms by means of 99mTc-HMPAO SPET with acetazolamide.

The detection of subclinical abnormalities in cerebral blood flow could be of great value in identifying diabetic patients at risk of stroke. The aim of this study was to assess the contribution of semiquantified post-acetazolamide technetium-99m hexamethylpropylene amine oxime single-photon emission tomography (99mTc-HMPAO SPET) in 15 diabetic patients with no clinical history of central neurological disease. After baseline 99mTc-HMPAO SPET, a second SPET scan was acquired after activation of the cerebrovascular reserve (CVR) with an injection of 1 g of acetazolamide (post-ACZ SPET). Semiquantitative analysis was made in 16 regions of interest (ROIs) drawn for each of the three supratentorial slices selected, and in two ROIs in the infratentorial slice. The CVR was calculated in each ROI by subtracting the decay-corrected baseline images from those obtained in the post-ACZ SPET and expressed as the percent increase in the average counts between the two scans. Baseline perfusion and CVR values in the study group were compared with the corresponding values in a control group. Of 750 cortical ROIs studied, 332 showed a decreased CVR (44.3%). The baseline perfusion SPET study showed hypoperfusion in 65 ROIs (8.6%) and hyperperfusion in 56 (7.4%). Of the 65 hypoperfused regions, 66.2% had a normal CVR and 33.8% had a decreased CVR, whereas of the 56 hyperperfused regions, 51.8% had a CVR within normal limits and 48.2% showed a decreased CVR. In conclusion, in comparison with baseline 99mTc-HMPAO SPET, the ACZ activation test provided additional information in the study of cerebrovascular impairment, and allowed characterisation of the subclinical abnormalities in the population studied. The technique may therefore prove useful in evaluating future preventive strategies for stroke in diabetic patients.

Acetazolamide↗
PubMed2001

Perioperative response of leptin and the tumor necrosis factor alpha system in morbidly obese patients. Influence of cortisol inhibition by etomidate.

BACKGROUND: Leptin, tumor necrosis factor alpha (TNFalpha) and soluble TNFalpha receptors are secreted by the adipose tissue. Surgery induces a complex cytokine and neurohormonal response. The aim of our study was to investigate the perioperative response of leptin and the TNFalpha system in morbidly obese patients submitted to gastroplasty, and the possible involvement of cortisol in their responses. METHODS: Serum cortisol, adrenocorticotropic hormone (ACTH), leptin, TNFalpha and soluble TNFalpha receptor I were measured in 22 morbidly obese women (11 anesthetized with thiopental and 11 with etomidate, a well known inhibitor of cortisol synthesis). Samples were collected before anesthesia induction, just before surgical incision, and 2, 4, 6, 12, 24 and 48 h after the start of surgery. RESULTS: Baseline serum leptin correlated with body mass index (r=0.567, P=0.007). Baseline serum leptin and TNFalpha were higher than normal. Cortisol release was inhibited in the etomidate group with a subsequent higher stimulation of ACTH release. A statistically significant decrease in serum leptin levels was observed in both groups at 2, 4, 6 and 48 h, compared with basal values. A similar decrease in serum TNFalpha levels was observed in both groups, but the decrease reached significance only in the etomidate group. Serum soluble TNFalpha receptor I did not decrease. No differences were found between the two groups in leptin, TNFalpha or soluble TNFalpha receptor I concentrations at any time. CONCLUSION: Serum leptin and TNFalpha levels decrease in obese patients during gastroplasty. Transitory inhibition of cortisol release does not alter this response.

Adrenocorticotropic Hormone↗
PubMed2001

Dendroaspis natriuretic peptide in hepatic cirrhosis.

OBJECTIVES: Dendroaspis natriuretic peptide (DNP) is a novel peptide that is structurally similar to atrial, brain, and C-type natriuretic peptides. Many natriuretic peptides are increased in hepatic cirrhosis, but the role of DNP in cirrhosis is unknown at present. The aim of the study was to investigate plasma levels of dendroaspis natriuretic-like immunoreactivity in cirrhosis. METHODS: We measured plasma concentrations of DNP by radioimmunoassay methods in 12 cirrhotic patients without ascites and 44 cirrhotic patients with ascites, and compared these values with 20 age-matched healthy subjects. Renal function, plasma cGMP concentration, plasma renin activity, and plasma endothelin concentration were measured in each patient. RESULTS: Patients without ascites had circulating levels of DNP similar to those of healthy subjects. By contrast, patients with ascites had increased circulating DNP levels compared to both patients without ascites and healthy subjects. In addition, circulating levels of DNP increased in relation to the severity of cirrhosis. Significant positive correlations were also found between DNP levels, endothelin concentrations, and plasma renin activity. CONCLUSIONS: The results of this study indicate that plasma DNP is increased in cirrhotic patients with ascites.

Adult↗
PubMed2001

Effects of long-term treatment with antipsychotics on serum leptin levels.

BACKGROUND: Abnormal regulation of the adipocyte-derived hormone leptin could play a role in body weight gain induced by antipsychotics. AIMS: To study the effects of long-term antipsychotic treatment on leptin levels in patients with schizophrenia. METHOD: Serum leptin levels were determined in 59 out-patients with chronic schizophrenia and in the same number of healthy subjects controlled by gender, age and body mass index. RESULTS: Leptin levels did not differ between patients and controls. Leptin levels in patients with schizophrenia correlated with weight gain, even after controlling for current weight, but did not show any association with clinical variables. Antipsychotic class tended to exert different effects over leptin levels (among atypicals, olanzapine induced a greater increase). CONCLUSIONS: Elevation of leptin levels induced by chronic antipsychotic treatment can be attributed to weight gain, but other mechanisms could be involved.

Adult↗
PubMed2000

Higher levels of serum copper in schizophrenic patients treated with depot neuroleptics.

The findings of previous research on the status of trace elements in patients with schizophrenia have been controversial. We studied 62 outpatients with a DSM-IV diagnosis of schizophrenia, and compared them with sex- and age-matched healthy controls. Serum copper levels were significantly higher in schizophrenic patients (mean 117.4 microg/dl; S.D. 23.4) than in healthy controls (105.6+/-27.9). Those patients on treatment with depot neuroleptics had higher copper levels. Zinc levels did not differ between patients and healthy controls. Altered levels of trace elements in schizophrenic patients may be a consequence of antipsychotic treatment.

Adult↗
PubMed2000

Different time course of circulating adhesion molecules and hyaluran during hepatic allograft rejection.

BACKGROUND: Inducible adhesion molecules are involved in cell-mediated allograft rejection. In addition, the endothelium is the main target of this process. This study investigated, whether soluble (s) forms of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) are elevated during cellular rejection and whether hyaluran is a useful marker of endothelial function in liver transplantation. METHODS: Serum levels of sICAM-1, sVCAM-1, and hyaluran were determined in 24 controls and 27 hepatic transplant recipients. These patients were divided in two groups: group I, 14 patients without rejection; and group II, 13 patients with rejection. Samples were collected on day 1 and 7 after transplantation, on the day of liver biopsy, and after treatment of the rejection. RESULTS: We found a significant increase in sICAM-1 levels in the postoperative period in the rejection group compared with the non rejection group. It persisted significantly elevated until the diagnosis of rejection was made. In contrast, sVCAM-1 was only significantly elevated in the rejection group when diagnosis of rejection was evident. Hyaluran levels were also significantly elevated in the rejection group at diagnosis of rejection. We noticed a significant decline in sICAM-1, sVCAM-1, and hyaluran levels after successful treatment of rejection. In addition, we observed in the non-rejection group a stable lower levels of hyaluran during the entire postoperative period. CONCLUSIONS: The release of circulating adhesion molecules is a prominent feature coinciding with the first episode of hepatic rejection. Differential patterns of sICAM-1 and sVCAM-1 exist during rejection. In addition, hyaluran levels may be a sensitive marker of liver endothelial cell function in the postoperative period of liver transplantation.

Adult↗
PubMed2000

Venous endothelial function in postmenopausal women who are receiving long-term estrogen and progestagen therapy.

OBJECTIVE: To test venous endothelial function during long-term hormone replacement therapy (HRT) and after treatment withdrawal. DESIGN: Measurement of dorsal hand-vein diameter by venous occlusion plethysmography during infusion of norepinephrine, bradykinin, NG-monomethyl L-arginine, and sodium nitroprusside. SETTING: Plethysmography and menopause units, University Hospital Marqués de Valdecilla, Santander, Spain. PATIENT(S): Twenty postmenopausal women, of whom 10 were assigned to receive no hormone replacement therapy (HRT) for 6 months after plethysmography (group A) and 10 were assigned to receive HRT for 6 months (group B). After 6 months, HRT was administered to group A and withdrawn from group B for another 6 months. INTERVENTION(S): Plethysmography at baseline and at 6 and 12 months. MAIN OUTCOME MEASURE(S): Dorsal hand-vein diameter measured by venous occlusion plethysmography during infusion of norepinephrine, bradykinin, NG-monomethyl L-arginine, or sodium nitroprusside. RESULT(S): At 6 months, the maximum dilation obtained with bradykinin was 48.8 +/- 7.58% in group A and 76.7 +/- 12.9% in group B. At 12 months, maximum bradykinin dilation increased to 74.3 +/- 14.2% in group A and decreased to 54.0 +/- 15.9% in group B. CONCLUSION(S): Long-term HRT with estrogen plus progestin improves endothelium-dependent vasodilation, but this effect is lost in a relatively short time. Endothelial function in dorsal hand veins is an easy-to-use plethysmography model that can be used in serial studies.

Bradykinin↗