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J Mesa

Publications and source records attributed to J Mesa.

At least 37 records · Page 2Linked to original sources
PubMed2000

Relationship of lipoprotein(a) and its phenotypes with the albumin excretion rate in diabetic patients: a multivariate analysis.

BACKGROUND/AIM: The possible association between lipoprotein(a) [Lp(a)] and albumin excretion rate (AER) is a topic that has generated conflicting views. The aim of this study was to determine the relationship between serum Lp(a) concentrations and AER in diabetic patients, taking into account Lp(a) phenotypes in a multivariate analysis. METHODS: For this purpose 191 consecutive diabetic patients (69 type 1 and 122 type 2) were included in the study. Lp(a) was determined by ELISA and its phenotypes by SDS-PAGE followed by immunoblotting. Lp(a) phenotypes were grouped by size in small (F, B, S1, S2), big (S3, S4) and null. RESULTS: Diabetic patients with an AER >20 microg/min presented higher Lp(a) concentrations than patients with an AER <20 microg/min: median 19 mg/dl versus 5 mg/dl (p < 0.0001). The differences remained at a significant level when the type of diabetes was considered. A linear correlation was observed between Lp(a) concentration and AER (type 1: r = 0.32, p = 0.01; type 2: r = 0.25, p < 0.05). The AER was independently correlated with Lp(a) concentrations in a multiple regression analysis (p < 0.01), and Lp(a) was independently associated with the presence of diabetic nephropathy in the logistic regression analysis. The overall frequency distribution of Lp(a) phenotypes differed significantly between patients with or without microalbuminuria (p < 0.05). In addition, the AER (microg/min) was different among the Lp(a) phenotypes: small 55 +/- 122 (median 4.9), big 58 +/- 123 (median 5.7) and null 3 +/- 2 (median 2.3); p = 0.01. The significant difference mainly resulted from low AER (<10 microg/min) detected in all patients with the null phenotype. CONCLUSIONS: In diabetic patients the serum Lp(a) concentration is associated with AER. Thus, the elevated cardiovascular risk observed in diabetic patients with a high AER could be related to the Lp(a) concentration. Finally, patients with the null Lp(a) phenotype can be considered as a group at low risk of the development of diabetic nephropathy.

Adult↗
PubMed2000

Vitreous levels of IGF-I, IGF binding protein 1, and IGF binding protein 3 in proliferative diabetic retinopathy: a case-control study.

OBJECTIVE: To evaluate vitreous levels of IGF-I and its binding proteins IGFBP-1 and IGFBP-3 in patients with proliferative diabetic retinopathy (PDR). Because intravitreal proteins are elevated in patients with PDR due to the disruption of the blood-retinal barrier, we have corrected vitreal IGF-I and IGFBPs by total vitreal proteins to avoid this confounding factor. RESEARCH DESIGN AND METHODS: We compared 21 diabetic patients with proliferative retinopathy (group A) and 13 nondiabetic patients (group B) in whom a vitrectomy was performed. Both groups were matched by age, serum IGF-I, IGFBP-1, and IGFBP-3 levels. Serum and vitreous levels of IGF-I, IGFBP-1, and IGFBP-3 were measured by immunological methods. Vitreal proteins were assessed by turbidimetric method. RESULTS: Vitreal levels of IGF-I were elevated in group A (median 1.35 ng/ml [range 0.3-8.7]) in comparison with group B (median 0.25 ng/ml [range 0-1.38]), P<0.001. After adjusting by vitreal proteins [ratio IGF-I (ng/ml)/protein (mg/ml)], the differences remain significant (P<0.005). Vitreal levels of IGFBP-1 and IGFBP-3 were also elevated in diabetic patients (IGFBP-1: group A, median 1.6 ng/ml [range 0.6-20.7]; group B, median 0.4 ng/ml [range 0.3-1.9], P<0.001. IGFBP-3: group A, median 102.6 ng/ml [range 53.9-350.8]; group B, median 29.0 ng/ml [range 3.2-87.8], P<0.001). However, when the ratio IGFBP/protein was considered, the differences were not significant. CONCLUSIONS: Intraocular synthesis contributes to elevated vitreous concentrations of IGF-I found in PDR. By contrast, unspecific increase of intravitreal proteins is the main factor explaining the elevated vitreous levels of IGFBP-1 and IGFBP-3 found in diabetic patients.

Case-Control Studies↗
PubMed1999

[Fibronectin and diabetes mellitus: the factors that influence its plasma concentrations and its usefulness as a marker of late complications].

BACKGROUND: The usefulness of plasma fibronectin (FNp) as a marker of late diabetic complications is controversial. The aim of the study was to assess the influence of several variables on FNp in diabetic patients and to determine its usefulness as a marker of late diabetic complications. PATIENTS AND METHODS: 79 diabetic patients randomly selected were included in the study. The clinical variables considered were: age, gender, body mass index (BMI), tobacco and alcohol consumption, type, duration and treatment of diabetes, hypertension, and diabetic late complications (macroangiopathy, retinopathy, nephropathy and neuropathy). The laboratory variables analyzed were: blood glucose, glycated hemoglobin, total cholesterol, HDL-cholesterol, LDL-cholesterol, tryglicerides, apolipoprotein AI, apolipoprotein B, microalbuminuria, creatinin and FNp. Statistical study included a multiple regression analysis taking FNp as the dependent variable. RESULTS: A direct correlation between FNp and BMI and also with tryglicerides was observed (r = 0.362; p = 0.002, and r = 0.234; p = 0.038, respectively). Higher levels of FNp were found in type 2 diabetic patients in comparison with type 1 (464 [SD, 127] versus 395 [SD, 96] mg/dl; p = 0.014). This difference was due to the higher BMI and tryglicerides concentrations observed in type 2 diabetic patients in comparison with type 1 (28.61 [SD, 4.67] versus 22.56 [SD, 2,.19] kg/m2; p < 0.001, and 4.24 [SD, 2.36] versus 2.52 [SD, 1.40] mmol/l, respectively). Multiple regression analysis showed that only BMI significantly influenced on FNp concentrations (r = 0.330; p = 0.004). No relation among FNp and late diabetic complications and other variables considered in the study was observed. CONCLUSIONS: FNp is not a useful marker of diabetic late complications and its concentrations are direct and independently influenced by BMI.

Adult↗
PubMed1999

Immobilization of the mallet finger. Effects on the extensor tendon.

Since the mallet finger that is treated with isolated splinting of the distal interphalangeal (DIP) joint can be moved freely proximal to the DIP joint, we sought to determine whether such motion might cause a tendon gap that could explain the extensor lag that often follows treatment. Experiments were performed on 32 cadaveric fingers with open mallet finger lesions, immobilizing either the DIP joint alone or both the DIP and PIP joints, while repeatedly flexing and extending the more proximal finger and wrist joints. For each experiment, the gap in the extensor tendon was measured. Joint motion proximal to the DIP joint and retraction of the intrinsics did not cause a tendon gap in a finger with a mallet lesion, supporting the convention that only the DIP joint needs to be immobilized.

Bone Wires↗
PubMed1999

A new statistical method for transfer coefficient calculations in the framework of the general multiple-compartment model of transport for radionuclides in biological systems.

A new and simple statistical procedure (STATFLUX) for the calculation of transfer coefficients of radionuclide transport to animals and plants is proposed. The method is based on the general multiple-compartment model, which uses a system of linear equations involving geometrical volume considerations. By using experimentally available curves of radionuclide concentrations versus time, for each animal compartment (organs), flow parameters were estimated by employing a least-squares procedure, whose consistency is tested. Some numerical results are presented in order to compare the STATFLUX transfer coefficients with those from other works and experimental data.

Animals↗
PubMed1998

Current global status of carotid artery stent placement.

Our purpose was to review the current status of carotid artery stent placement throughout the world. Surveys were sent to major interventional centers in Europe, North and South America, and Asia. Information from peer-reviewed journals was also included and supplemented the survey. The survey asked various questions regarding the patients enrolled, procedure techniques, and results of carotid stenting, including complications and restenosis. Of the centers which were sent surveys, 24 responded. The total number of endovascular carotid stent procedures that have been performed worldwide to date included 2,048 cases, with a technical success of 98.6%. Complications that occurred during carotid stent placement or within a 30-day period following placement were recorded. Overall, there were 63 minor strokes, with a rate of occurrence of 3.08%. The total number of major strokes was 27, for a rate of 1.32%. There were 28 deaths within a 30-day postprocedure period, resulting in a mortality rate of 1.37%. Restenosis rates of carotid stenting have been 4.80% at 6 mo. Endovascular stent treatment of carotid artery atherosclerotic disease is growing as an alternative to vascular surgery, especially for patients that are at high risk for standard carotid endarterectomy. The periprocedural risks for major and minor strokes and death are generally acceptable at this early stage of development.

Angioplasty, Balloon↗
PubMed1997

[Differentiated thyroid carcinoma, 1972-1992. Follow-up, detection of recurrences and prognostic factors].

BACKGROUND: There is no consensus about the treatment and the follow-up of differentiated thyroid carcinoma (DTC), because in some patients, currently known prognostic factors cannot predict the course of the disease. The aim of this work has been to review the results of the treatment of our patients with DTC and to assess the prognostic factors. PATIENTS AND METHODS: We include, retrospectively, 204 patients with DTC (54 males and 150 women) with a men (SD) age of 38 (23) years, attending to a terciary university hospital. The follow-up is 9.2 (6) years (range, 2-22 years). They all underwent near total thyroidectomy, ablative doses of radioactive iodine (131INa) and L-thyroxine to suppress thyroid stimulating hormone (TSH) levels. At least once a year, a clinical examination, a whole-body scan (WBS) with 131INa and serum thyroglobulin (Tg) measurements were performed in hypothyroid state. In the statistics, chi 2 test, univariate analysis, Student's t test, Kaplan-Meier method, Mantel-Cox test and multiple regression analysis were employed. RESULTS: The survival rate was 89.05%. Twenty patients died of DTC (9.8%) (papillary 8 [6%], follicular 12[17%]). Surgical complications (recurrent nerve palsy or permanent hypoparathyroidism) were seen in 5% of the patients. The sensitivity of WBS to detect distant metastases or local (neck) involvement was 71% (initial 100%, late 71%). Tg sensitivity was 85% (initial 95%, late 73%). Factors associated to a poor prognosis were age > 40 years (p < 0.0001), follicular carcinoma (p < 0.02) and initial stages III and IV (p < 0.0001). CONCLUSIONS: The mortality and complications rates in our patients with differentiated thyroid carcinoma validate our management schedule. Tg measurements are more sensitive than WBS to detect distant or local metastases; however, sensitivity of both techniques was lower in the detection of late metastases. Age below 40 years, papillary carcinoma and initial stages I and II are factors of better prognosis.

Adenocarcinoma, Follicular↗
PubMed1997

Comparison of aceclofenac with piroxicam in the treatment of osteoarthritis.

A multicentre, double-blind, randomised, parallel group study was undertaken to investigate the efficacy and safety of aceclofenac (123 patients, 100 mg twice daily) in comparison to piroxicam (117 patients, 20 mg once daily and placebo once daily) in patients with osteoarthritis of the knee. The treatment period of two months was preceded by a washout period of one week duration. On completion of the study, patients in both aceclofenac and piroxicam-treated groups exhibited significant improvement in pain intensity and functional capacity of the affected knee, as represented by the Osteoarthritis Severity Index (OSI) (p < 0.0001 and p < 0.001 respectively). This was further substantiated following the patient's assessment of pain intensity using the Visual Analogue Scale (VAS), in which significant improvements were demonstrated at all time points for each treatment group (p < 0.001). Although both treatment groups showed a significant improvement in all investigator's clinical assessments (functional exploration of the knee, knee flexion and extension (EXT)), there were no significant differences between the groups. There was, however, a more rapid improvement in knee flexion in the aceclofenac group after 15 days of treatment. Both aceclofenac and piroxicam were well tolerated by patients, the most commonly reported adverse events being gastrointestinal, although their incidence was low. Only 24 patients on aceclofenac, as opposed to 33 on piroxicam complained of dyspepsia, epigastralgia and pyrosis. While 7 patients in each group were withdrawn because of adverse events, only one patient with piroxicam was withdrawn because of severe upper gastrointestinal bleeding. Twice as many reports of fecal blood loss were made in the piroxicam group in comparison to the aceclofenac group. In summary, this study confirms the therapeutic efficacy of aceclofenac and suggests that it is a well-tolerated alternative NSAID to piroxicam in the treatment of osteoarthritis.

Adult↗
PubMed1997

Vitreous levels of vascular endothelial growth factor are not influenced by its serum concentrations in diabetic retinopathy.

Vascular endothelial growth factor (VEGF) plays a major role in the development of neovascularization in proliferative diabetic retinopathy (PDR). The source of intravitreous VEGF is presumably ischaemic retina, but increased levels derived from serum cannot be excluded. The aim of the study is to determine the intravitreous concentrations of VEGF in diabetic patients with PDR and to investigate whether serum VEGF could contribute to the intravitreous concentration. For this purpose, we studied 20 diabetic patients (5 IDDM and 15 NIDDM) with PDR in whom a vitrectomy was performed (group A). Non-diabetic patients (n = 13) with other conditions requiring vitrectomy served as a control group (group B). In both groups, VEGF was determined in serum and undiluted vitreous samples obtained simultaneously. Furthermore, serum VEGF was determined in 69 healthy control subjects (group C) and 39 diabetic patients without microvascular complications (group D). Vitreous and serum VEGF was determined by ELISA (R & D Systems, Abingdon, UK); intra-assay CV 3.8%, interassay CV 5.1%. Intravitreous concentrations of VEGF were strikingly higher in group A (median 1.75 ng/ ml, range 0.33-6.66) in comparison with group B (median 0.009 ng/ml, range 0.009-0.038); p < 0.0001. This difference remained significant after adjusting for intravitreous protein concentration (p < 0.05). Differences in serum VEGF among the groups included in the study were not found. We conclude that the high vitreous levels of VEGF observed in diabetic patients with PDR cannot be attributed to serum diffusion across the blood-retinal barrier. Therefore, intraocular synthesis is the main contributing factor for the high vitreous VEGF concentrations observed in PDR.

Adult↗
PubMed1997

Integral porous femoral stem. 5-to 8-Year follow-up study.

The outcome of total hip arthroplasty without cement was prospectively followed in patients who received a titanium taper wedge femoral component with a circumferential titanium plasma spray coating on the proximal surface (Integral femoral stem, Biomet, Warsaw, IN). One hundred ninety femoral components were implanted in 179 patients. Nine patients (9 hips) died prior to their 5-year examination, leaving 170 patients available for follow-up evaluation. Thirty-one of the 170 patients (33 hips) were lost at an intermediate follow-up period of 5 years. (mean, 5.8 years, range; 5-8 years), giving a follow-up rate of 82% for patients and hips. The preoperative diagnoses included osteoarthritis (91 hips), avascular necrosis (38), post-traumatic arthritis (10), rheumatoid arthritis (4), congenital dislocation of the hip (3), and fractures (2). The 78 men and 61 women had a mean age of 55 years (range, 18-81 years) and a mean weight of 81 kg (range, 50-136 kg). Pre-operative Harris pain and function scores for the hip were 19.9 (range, 0-40) and 55.6 (range, 12-84), respectively. At the most recent follow-up visit, the mean pain score increased to 41.2 (range, 10-44) and the mean function score increased to 93.5 (range, 6-100). Thigh pain was present in 4% of the hips at the most recent follow-up visit. Radiographically, 99% of the femoral components demonstrated spot welds in the porous-coated zone. Two hips had demarcation of the femoral component in the porous-coated zone consistent with fibrous fixation. None of the femoral stems had been revised and there were no signs of aseptic loosening. Additionally, there were no cases of pain that could be directly attributed to the stem and there was no evidence of distal femoral osteolysis. It is concluded that the integral femoral stem provides excellent clinical and radiographic results at intermediate follow-up periods.

Adolescent↗
PubMed1997

Relationship between lipoprotein(a) phenotypes and albumin excretion rate in non-insulin-dependent diabetes mellitus: protective effect of 'null' phenotype?

The possible association between lipoprotein(a) [Lp(a)] and albumin excretion rate (AER) is a topic that generates conflicting views. In addition, Lp(a) phenotypes have not previously been considered as factors influencing AER. In order to clarify this issue, we studied 70 non-insulin-dependent diabetes mellitus (NIDDM) patients without clinically detectable macroangiopathy, 27 with microalbuminuria and 43 without it. Both groups were matched for the known variables that could influence AER and serum Lp(a) levels. Lp(a) was determined by enzyme-linked immunosorbent assay (ELISA), and Lp(a) phenotypes were assessed by electrophoresis followed by immunoblotting. Lp(a) phenotypes were grouped as follows: 'small' (F, S1 and S2), 'big' (S3 and S4) and 'null'. The NIDDM patients with microalbuminuria presented higher serum Lp(a) concentrations than the patients without it [15.7 mg dL-1 (95% CI 0.5-36.5) vs. 4.5 mg dL-1 (95% CI 0.1-18.5); P < 0.001] and a direct correlation between Lp(a) and AER was observed (r = 0.34; P < 0.01). AER was significantly different when Lp(a) phenotypes were considered ['small': median 19 micrograms min-1 (range 1-195); 'big': median 9.5 micrograms min-1 (range 1-186); 'null': 4 micrograms min-1 (range 1-9); P = 0.04]. None of the NIDDM patients with a 'null' phenotype showed an AER of > 10 micrograms min-1. In conclusion, this case-control study provides evidence that microalbuminuria is associated with high serum Lp(a) in NIDDM without clinically detectable macroangiopathy. Furthermore, NIDDM patients with a 'null' phenotype could be considered at low risk for the development of microalbuminuria.

Aged↗
PubMed1997

False-positive results of basal and pentagastrin-stimulated calcitonin in non-gene carriers of multiple endocrine neoplasia type 2A.

Direct DNA analysis permits accurate identification of gene carriers in kindred members with multiple endocrine neoplasia type 2A (MEN 2A). The aim of this study was to assess the specificity of basal and pentagastrin stimulated calcitonin levels in 3 family members with MEN 2A. For this purpose 53 members of 3 consecutive families with MEN 2A were evaluated in a university medical center. Serum calcitonin, basal and stimulated, was determined by a commercial RIA. RET protooncogene analysis was carried out by automatic DNA sequencing and adequate digestion of PCR amplified products for exons 10 and 11. Two distinct mutations in the RET protooncogene were identified. A T-->A transition at position 1783 (codon 618) in exon 10 was detected in one family, and a G-->A replacement at position 1832 (codon 634) in exon 11 in the others. In non-gene carriers we obtained 6.6% of false-positive results for basal calcitonin and 15.4% for the pentagastrin provocative test. We conclude that the specificity of basal and pentagastrin-stimulated calcitonin is rather limited and RET protooncogene analysis must be the first line screening procedure in order to identify gene carriers.

Adolescent↗
PubMed1996

Serum concentrations of laminin-P1 in diabetes mellitus: usefulness as an index of diabetic microangiopathy.

OBJECTIVE: To assess the influence of several variables on serum laminin-P1 (Lam-P1) and to evaluate its usefulness as a serum marker of diabetic microangiopathy. MATERIAL AND METHODS: We determined Lam-P1 by serum radioimmunoassay in 121 controls and 176 diabetic patients, 58 type 1 (insulin dependent) and 118 type (non-insulin dependent), grouped according to retinal status and urinary albumin excretion. The variables evaluated were: age, gender, body mass index, blood pressure, consumption of tobacco and alcohol, type of diabetes, duration of disease, fasting blood glucose, HbA1, cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and apolipoproteins (A1, B). Imprecision for laminin determination was: 3.6% intrassay; 5.8% interassay. STATISTICS: Student's t-test, ANOVA, ANCOVA, and multiple regression analysis. RESULTS: In diabetic patients Lam-P1 was higher than in controls (X = 1.63 +/- S.D. 0.36 vs. X = 1.40 +/- S.D. 0.18 U ml-1; P < 0.001) and only correlated with age (P = 0.002). Lam-P1 was higher in diabetics with proliferative retinopathy than in patients with non-proliferative retinopathy and without retinopathy (X = 2.17 +/- S.D. 0.49 U ml-1 vs. X = 1.71 +/- S.D. 0.22 U ml-1 vs. X = 1.47 +/- S.D. 0.26 U ml-1; P < 0.001). Patients with macroalbuminuria presented higher serum Lam-P1 than patients with micro or normoalbuminuria (X = 2.39 +/- S.D. 0.53 U ml-1 vs. X = 1.78 +/- S.D. 0.23 U ml-1 vs. X = 1.51 +/- S.D. 0.29 U ml-1; P < 0.001). These differences remained significative when patients were age-adjusted. CONCLUSIONS: Lam-P1 could be useful as an index of diabetic microangiopathy but patient's age should be considered.

Adult↗
PubMed1996

High prevalence of hepatitis C virus infection in diabetic patients.

OBJECTIVE: To evaluate the prevalence of hepatitis C virus (HCV) infection in diabetic patients and to investigate the influence of several epidemiological and clinical factors on HCV infection. RESEARCH DESIGN AND METHODS: A total of 176 consecutive diabetic patients were compared with 6,172 blood donors, matched by recognized risk factors to acquire HCV infection. Serologic testing for anti-HCV was done using a second-generation commercial enzyme-linked immunosorbent assay (ELISA) and an immunoblot assay was performed in anti-HCV positive samples to confirm HCV specificity. Diabetic patients were divided in two groups according to their HCV antibody status and analyzed for the following variables: age, sex, type of diabetes, duration of disease, mode of therapy, late diabetic complications, previous blood transfusions, intravenous drug addiction, hospital admissions, major surgical procedures, and liver function tests (LFTs). RESULTS: A higher prevalence of HCV infection was observed in diabetic patients in comparison with blood donors (11.5 vs. 2.5%; P < 0.001; odds ratio 4.39; 95% Cl2.61-7.24). We did not detect any particular epidemiological factor for HCV infection in anti-HCV positive diabetic patients. In these patients, abnormal LFTs were observed in 72.3%, compared with only 24.7% of anti-HCV negative diabetic patients (P < 0.001). CONCLUSIONS: A high prevalence of HCV infection was detected in diabetic patients, and most of anti-HCV positive patients presented with abnormal LFTs. Therefore, testing for HCV infection of diabetic patients with an abnormal LFT is mandatory. The lack of any particular epidemiological factor for HCV infection in our diabetic population suggests that HCV may have a direct role in the development of diabetes.

Adult↗