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J Lima

Publications and source records attributed to J Lima.

At least 19 recordsLinked to original sources
PubMed2005

Clinical efficacy of anti-pneumococcal vaccination in patients with COPD.

BACKGROUND: A study was undertaken to evaluate the clinical efficacy of the 23-valent pneumococcal polysaccharide vaccine (PPV) in immunocompetent patients with chronic obstructive pulmonary disease (COPD). METHODS: A randomised controlled trial was carried out in 596 patients with COPD of mean (SD) age 65.8 (9.7) years, 298 of whom received PPV. The main outcome was radiographically proven community acquired pneumonia (CAP) of pneumococcal or unknown aetiology after a mean period of 979 days (range 20-1454). RESULTS: There were 58 first episodes of CAP caused by pneumococcus or of unknown aetiology, 25 in the intervention group and 33 in the non-intervention group. Kaplan-Meier survival curves for CAP did not show significant differences between the intervention and non-intervention arms (log rank test = 1.15, p = 0.28) in the whole group of patients. The efficacy of PPV in all patients was 24% (95% CI -24 to 54; p = 0.333). In the subgroup aged <65 years the efficacy of PPV was 76% (95% CI 20 to 93; p = 0.013), while in those with severe functional obstruction (forced expiratory volume in 1 second <40%) it was 48% (95% CI -7 to 80; p = 0.076). In younger patients with severe airflow obstruction the efficacy was 91% (95% CI 35 to 99; p = 0.002). There were only five cases of non-bacteraemic pneumococcal CAP, all in the non-intervention group (log rank test = 5.03; p = 0.025). Multivariate analysis gave a hazard ratio for unknown and pneumococcal CAP in the vaccinated group, adjusted for age, of 0.20 (95% CI 0.06 to 0.68; p = 0.01). CONCLUSIONS: PPV is effective in preventing CAP in patients with COPD aged less than 65 years and in those with severe airflow obstruction. No differences were found among the other groups of patients with COPD.

Adult↗
PubMed2005

Somatic and germline mutation in GRIM-19, a dual function gene involved in mitochondrial metabolism and cell death, is linked to mitochondrion-rich (Hurthle cell) tumours of the thyroid.

Oxyphil or Hurthle cell tumours of the thyroid are characterised by their consistent excessive number of mitochondria. A recently discovered gene, GRIM-19 has been found to fulfil two roles within the cell: as a member of the interferon-beta and retinoic acid-induced pathway of cell death, and as part of the mitochondrial Complex I assembly. In addition, a gene predisposing to thyroid tumours with cell oxyphilia (TCO) has been mapped to chromosome 19p13.2 in one family. A cluster of genes involved in mitochondrial metabolism occurs in this region; one of these is GRIM-19. We have searched for GRIM-19 mutations in a series of 52 thyroid tumours. Somatic missense mutations in GRIM-19 were detected in three of 20 sporadic Hurthle cell carcinomas. A germline mutation was detected in a Hurthle cell papillary carcinoma arising in a thyroid with multiple Hurthle cell nodules. No mutations were detected in any of the 20 non-Hurthle cell carcinomas tested, nor in any of 96 blood donor samples. In one of the sporadic Hurthle cell papillary carcinomas positive for GRIM-19 mutation, we have also detected a ret/PTC-1 rearrangement. No GRIM-19 mutations were detected in any of the six cases of known familial Hurthle cell tumour tested, so that our results do not support the identification of GRIM-19 as the TCO gene. The GRIM-19 mutations we have detected are the first nuclear gene mutations specific to Hurthle cell tumours to be reported to date; we propose that such mutations can be involved in the genesis of sporadic or familial Hurthle cell tumours through the dual function of GRIM-19 in mitochondrial metabolism and cell death.

Adenoma, Oxyphilic↗
PubMed2004

Risk factors for intracardiac thrombus in patients with recent ischaemic cerebrovascular events.

BACKGROUND: Intracardiac thrombus is a common cause of cardiogenic cerebral ischaemia. Stroke recurrence is high, but thrombus detection with therapeutic intervention can reduce the risk. Accurate detection requires transoesophageal echocardiography (TOE), which is semi-invasive and costly. OBJECTIVE: To identify risk factors for cardiac thrombus, enabling selection of patients for TOE and initiation of measures to prevent the formation of cardiac thrombus. METHODS: 151 consecutive patients with ischaemic stroke or transient ischaemic attacks (mean age 62 years) underwent TOE for intracardiac thrombus detection within one week of a qualifying event. RESULTS: Intracardiac thrombus was found in 26% of the patients (70% in the left atrial appendage). Multivariate analysis indicated the following clinical correlates: large stroke, odds ratio (OR) = 2.8 (95% confidence interval, 1.2 to 6.4); symptomatic coronary artery disease, OR = 3.0 (1.2 to 7.4); and ECG evidence of ischaemia, OR = 2.8 (1.1 to 7.7). Neither carotid stenosis >70%, nor stroke location correlated with the presence of thrombus. CONCLUSIONS: Clinical factors correlate with and appear to be risk factors for cardiac thrombus in patients with recent cerebral ischaemia. These may be used to select appropriate patients for invasive and costly TOE investigation, irrespective of the presence of significant carotid stenosis (>/=70%) or stroke location.

Aged↗
PubMed2004

Kinetics and dynamic evaluation of specific immunotherapy.

UNLABELLED: Specific immunotherapy (SIT) is frequently used in the treatment of allergic diseases. However, the mechanisms by which SIT achieves clinical improvement remained unclear. We decided to study the in vivo kinetics of this therapy, using a nuclear medicine approach (leukocytes labelled with 99mTc-HMPAO) in patients on maintenance doses of specific immunotherapy with confirmed clinical efficacy. MATERIAL AND METHODS: We studied 13 allergic patients grouped according to different treatment schedules: subcutaneous aqueous allergenic extract (3 latex and 2 hymenoptera venom), subcutaneous depot extract (2 house dust mite and 2 pollens), subcutaneous modified allergens (2 pollens), sublingual extract (2 house dust mites). The control group included two allergic patients submitted to subcutaneous injections of bacterial extract (1 patient--positive control), and aqueous solution (1 patient). At the same time that the therapeutic allergen was administered subcutaneously, the autologous labelled white cells were injected intravenously in a peripheral vein in the contralateral arm. A thoracic dynamic acquisition of 60 mins, 64x64 matrix, 2 frame/min, in anterior view was performed. Static acquisition for 256x256 matrix, during 5 mins each at 60, 90, 120, 180, 240, 300 and 360 mins after the administration of the radiolabelled leukocytes, in thoracic (anterior and posterior), and abdominal view were performed. During the examination, the local erythema was monitored. A similar procedure was undertaken for Sublingual administration of immunotherapy. RESULTS: The inflammatory activity at the site of SIT injection (aqueous depot extract) started in the first hour and the increase was time related. For modified allergen extract and sublingual SIT the activity was present since the beginning of the administration. The ascendant lymphatic drainage, which was directed to the homolateral axillary region, to the lymphoid tissue of the upper mediastinum and to the anterior region of the neck began earlier. Thoracic focalisations were present for all the patients, whereas bowel focalisations were only observed for the subcutaneous route of administration. Sublingual SIT did not induce axillary or intestinal inflammatory focalisations, even though the patients had swallowed the allergenic extract. The uptake coefficient in individualized areas corrected to the uptake coefficient background was also studied. CONCLUSIONS: For the subcutaneous route of administration, except for glutaraldehyde-modified allergen, the local inflammatory activity at the allergenic injection site was significantly higher in depth and was time dependent, maintaining activity even after complete disappearance of the erythema and/or wheal. These results express a prompt inflammatory involvement of the immune system with this allergenic therapy, which was unexpected until now. We also observed differences concerning allergic diseases, the type of allergenic extracts and routes of administration.

Administration, Sublingual↗
PubMed2003

Engraftment syndrome following autologous hematopoietic stem cell transplantation: definition of diagnostic criteria.

Engraftment syndrome (ES) is an increasingly reported complication of hematopoietic stem cell transplantation (HSCT). In order to better characterize the clinical criteria for the diagnosis of ES, we retrospectively analyzed 125 autologous HSCT recipients. ES was first defined as the presence of noninfectious fever plus skin rash. Patients with and without these findings were compared (univariate and multivariate analyses) regarding the presence of weight gain, hypoalbuminemia, pulmonary infiltrates, diarrhea, neurological manifestations and jaundice. The variables that are significantly more frequent in patients with fever and skin rash were incorporated in the definition criteria. The final diagnostic criteria were noninfectious fever plus any of the following: skin rash, pulmonary infiltrates or diarrhea. The incidence of ES was 20%. The single risk factor for ES by multivariate analysis was a diagnosis other than Hodgkin's disease (odds ratio 6.17, 95% confidence interval 1.38-27.78). Patients with ES received empirical antifungal therapy more frequently than patients without the syndrome (40 vs 19%, P=0.03), and had a longer duration of hospitalization (P=0.0007). The prospective application of these diagnostic criteria may have a favorable impact on the early diagnosis of the syndrome, with the initiation of corticosteroids and a reduction in the unnecessary use of antimicrobial agents.

Adolescent↗
PubMed2003

Memory and executive functions in aneurysms of the anterior communicating artery.

The cognitive outcome of three groups of patients, who had undergone surgery for repair of a single ruptured intracranial aneurysm, was evaluated. We assessed performance on tests of executive functions and memory in a group of 15 patients tested at least 3 months after an aneurysm of the anterior communicating artery (ACoA) and in a group of 12 patients tested in the first month after the same pathology. Acute patients were more impaired overall than chronic ones, but the two groups significantly differed on two executive and one memory test. The performance of the ACoA patients was also compared to the performance of a group of 10 patients who had undergone surgery for an aneurysm located on the posterior communicating artery (PCoA) at least 3 months before the examination. Chronic ACoA and PCoA patients significantly differed in two memory and in two executive tests performance, with posterior patients being more impaired than anterior. An unexpected finding was the impairment of semantic memory in ACoA patients.

Adult↗
PubMed2003

Mortality and prognostic factors in Spanish patients with systemic sclerosis.

OBJECTIVE: To determine survival and mortality in a cohort of Spanish patients with scleroderma (systemic sclerosis, SSc) and to analyse whether survival is influenced by demographic, clinical or immunological variables or the extent of skin involvement. METHODS: The study included 79 patients diagnosed with SSc and taking part in a study to determine the extent of sclerosis, visceral involvement and immunological alterations. We studied the number of observed and expected deaths (the expected number being based on age- and sex-specific rates in the background population) and derived standardized mortality ratios with their 95% confidence intervals (CI). Cumulative survival after onset of the first symptom was estimated according to the Kaplan-Meier method. The Cox method was used to identify the prognostic factors. RESULTS: The mortality rate was 0.0249 deaths per person-year. Survival at 15 yr was 0.62 (95% CI 0.410-0.778). The standardized mortality ratio was 429.4% (95% CI 222-750). On crude analysis, lung involvement [forced vital capacity (FVC) <70%, pulmonary hypertension], SSc renal crisis, an active capillaroscopic pattern, pericardial effusion and age over 60 yr at diagnosis were associated with shorter survival. On multivariate analysis, only age at diagnosis over 60 yr, FVC <70% and SSc renal crisis were independent prognostic factors. CONCLUSIONS: The mortality rate associated with SSc showed a four-fold increase compared with the background population. Lung involvement and sclerodermal renal crisis were found to be independently associated with reduced survival.

Adolescent↗
PubMed2002

Specific haplotypes of the RET proto-oncogene are over-represented in patients with sporadic papillary thyroid carcinoma.

BACKGROUND: Papillary thyroid carcinoma (PTC), which may be sporadic (95%) or familial (5%), has a prevalence adjusted for age in the general population of 1:100 000. Somatic rearrangements of the RET proto-oncogene are present in up to 66% of sporadic tumours, while they are rarely found in familial cases. PURPOSE: In order to determine if some variants of this gene, or a combination of them, might predispose to PTC, we looked for an association of RET haplotype(s) in PTC cases and in controls from four countries matched for sex, age, and population. METHODS: Four single nucleotide polymorphisms (SNPs) across the RET coding sequence were typed and haplotype frequencies were estimated. Genotype and haplotype distributions were compared among these cases and controls. RESULTS: Ten haplotypes were observed, the seven most frequent of which have been previously described in sporadic Hirschsprung patients and controls. The single locus analyses suggested association of exon 2 and exon 13 SNPs with sporadic PTC. The haplotype analysis showed over-representation of one haplotype in French and Italian sporadic PTC, whereas a different haplotype was significantly under-represented in French familial PTC. CONCLUSIONS: Our data suggest that some variants of RET and some specific haplotypes may act as low penetrance alleles in the predisposition to PTC.

Age Factors↗
PubMed2001

Frequency and predictors of stroke death in 5,888 participants in the Cardiovascular Health Study.

BACKGROUND: Few population-based studies have examined in detail issues of stroke-related deaths in elderly people. METHODS: Participants in the Cardiovascular Health Study (CHS) are 65 years of age or older, have had extensive baseline evaluations, and have been followed-up for fatal and nonfatal cardiovascular and cerebrovascular disease outcomes. Investigators adjudicated these outcomes and classified strokes by types and subtypes. RESULTS: Over 7 years, 1,310 (22.2%) of 5,888 participants died, and 455 (7.7%) experienced incident stroke. For the 5,888, stroke mortality was 3.2 per 1,000 person-years. For the 455, it was 36.1 per 1,000 person-years, with the most lethal type being hemorrhagic and the ischemic subtype being cardioembolic. After controlling for age and stroke type, the only other independent predictor of death after any stroke was poor performance on a timed walk measured before the incident stroke. Considering only ischemic stroke, the independent predictors of death were African American race and poor performance on timed walk. CONCLUSION: In CHS, death attributable to stroke is common. As in other studies, the most lethal stroke type was hemorrhagic, and ischemic stroke subtype, cardioembolic. Slow walking, possibly a measure of frailty, was associated with an increased risk of death of stroke. Finally, African Americans faced a greater risk of death than others after an ischemic stroke.

Aged↗
PubMed2001

Interactions between calcium, phosphate, and albumin on the surface of titanium.

The deposition of calcium phosphate on chemically polished commercially pure titanium immersed in Hank's balanced salt solution (HBSS) with bovine serum albumin (BSA) (concentrations 0 and 4 mg/mL) has been investigated. Electrochemical techniques, 125I labeling of albumin, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used. A tricalcium phosphate layer with a thickness of ca. 1 microm was formed for periods of immersion in HBSS ranging between 1 and 2 weeks. A concentration of 4 mg/mL of BSA prevented its formation, even for periods as long as 1 month. In the absence of BSA, the electrochemical behavior of titanium specimens was significantly affected by the length of immersion time, reflecting the changes that slowly occur on their surface. In the presence of BSA, the surfaces maintained most of their original electrochemical activity. Surface studies have shown that calcium and phosphate become incorporated in the surface at very early stages of immersion. Albumin, which was rapidly adsorbed on titanium, was slowly desorbed when titanium was placed in HBSS. Protein and phosphate may coexist on the same surface, but initially adsorbed albumin molecules prevent the precipitation of a thick layer of tricalcium phosphate.

Animals↗
PubMed2001

Morphologic capillary changes and manifestations of connective tissue diseases in patients with primary biliary cirrhosis.

The objective of this study was to investigate the presence of nailfold capillary abnormalities and extrahepatic signs of connective tissue disease in patients with primary biliary cirrhosis (PBC), as compared to patients with other chronic liver diseases. We evaluated 22 patients with PBC and 15 patients with other chronic liver diseases as a control group. Nailfold capillaroscopy was performed by two observers blinded to clinical findings using a Wild M3 stereomicroscope with an Intralux 5000 Volpi cold light lamp. We detected nailfold capillary abnormalities in 20 out of 22 (91%) PBC patients. Twelve of these 20 patients (54%) showed capillary alterations characteristic of systemic sclerosis. In the control group only two out of 15 patients (13%) presented alterations and in both cases they were a non-specific type. The presence of nailfold capillary abnormalities was significantly greater in PBC patients than in the control group (P < 0.001). Eleven out of the 22 PBC patients (50%) had extrahepatic signs of connective tissue disease and most of them were related to systemic sclerosis; patients with other chronic liver diseases did not present rheumatic manifestations (P < 0.001). In PBC patients there was a significant association between systemic sclerosis capillary pattern and rheumatic manifestations (P < 0.03). The high prevalence of nailfold capillary abnormalities characteristic of systemic sclerosis in patients with PBC and the correlation with sclerodermal manifestations suggests that this capillaroscopic finding could be a useful indicator to investigate rheumatic manifestations in these patients.

Adult↗
PubMed2001

Mini-sternotomy for the treatment of aortic valve lesions.

OBJECTIVE: To compare inverted-L mini-sternotomy performed above the sternal furcula with conventional sternotomy in patients with aortic valve diseases who undergo surgical treatment. METHODS: We operated upon 30 patients who had aortic valve lesions that had clinical and hemodynamic findings. All patients underwent inverted-L sternotomy, which extended from above the manubrium of the sternum to the 3rd right intercostal space, without opening the pleural cavity. Their ages ranged from 32 to 76 years, and 18 were males and 12 were females. We used negative pressure in a venous 1/4-inch cannula, and the patients were maintained in Trendelemburg's position. Twenty-seven patients received bioprostheses with diameters ranging from 23 to 29mm. Three patients underwent only removal of the calcifications of the aortic valve leaflets and aortic commissurotomy. RESULTS: The mean duration of anoxic cardiac arrest was 63.11min. Access was considered good in all patients. One death was due to pulmonary and renal problems not related to the incision. All patients had a better recovery in the intensive care unit, got out of bed sooner, coughed more easily, and performed prophylactic physiotherapeutic maneuvers for respiratory problems more easily and with less pain in the incision. Early ambulation was more easily carried out by all patients. CONCLUSION: Mini-sternotomy proved to be better than the conventional sternotomy because it provided more comfort for the patients in the early postoperative period, with less pain and greater desire for early ambulation and all its inherent advantages.

Adult↗
PubMed2000

Visualization and temporal/spatial characterization of cardiac radiofrequency ablation lesions using magnetic resonance imaging.

BACKGROUND: The purpose of this study was to describe a system and method for creating, visualizing, and monitoring cardiac radiofrequency ablation (RFA) therapy during magnetic resonance imaging (MRI). METHODS AND RESULTS: RFA was performed in the right ventricular apex of 6 healthy mongrel dogs with a custom 7F nonmagnetic ablation catheter (4-mm electrode) in a newly developed real-time interactive cardiac MRI system. Catheters were positioned to intracardiac targets by use of an MRI fluoroscopy sequence, and ablated tissue was imaged with T2-weighted fast spin-echo and contrast-enhanced T1-weighted gradient-echo sequences. Lesion size by MRI was determined and compared with measurements at gross and histopathological examination. Ablated areas of myocardium appeared as hyperintense regions directly adjacent to the catheter tip and could be detected 2 minutes after RF delivery. Lesions reached maximum size approximately 5 minutes after ablation, whereas lesion signal intensity increased linearly with time but then reached a plateau at 12.2+/-2.1 minutes. Lesion size by MR correlated well with actual postmortem lesion size and histological necrosis area (55.4+/-7.2 versus 49.7+/-5.9 mm(2), r=0.958, P<0.05). CONCLUSIONS: RFA can be performed in vivo in a new real-time interactive cardiac MRI system. The spatial and temporal extent of cardiac lesions can be visualized and monitored by T2- and T1-weighted imaging, and MRI lesion size agrees well with actual postmortem lesion size. MRI-guided RFA may be a useful approach to help facilitate anatomic lesion placement and to provide insight into the biophysical effects of new ablation techniques and technologies.

Animals↗
PubMed2000

Abnormalities of erythrocyte membrane fluidity, lipid composition, and lipid peroxidation in systemic sclerosis: evidence of free radical-mediated injury.

OBJECTIVE: To elucidate whether oxidative injury occurs in systemic sclerosis (SSc) and whether it affects the erythrocyte membrane (EM) properties. METHODS: EM fluidity and lipid composition (cholesterol:phospholipid molar ratio [C:PL], fatty acid composition) were studied in 52 patients with SSc and in 53 subjects without SSc (32 with primary Raynaud's phenomenon [RP] and 21 healthy subjects [controls]). Fluidity was measured as the fluorescence anisotropy of the hydrophobic fluorescent probe DPH (1,6-diphenyl-1,3,5-hexatriene). Lipid peroxidation products were determined as thiobarbituric acid-reactive substances (TBARS). RESULTS: EM fluidity was significantly lower in SSc patients than in primary RP patients and controls (P < 0.001). The EM C:PL molar ratio was significantly higher in SSc patients than in primary RP patients and controls (P < 0.05). Levels of EM polyunsaturated n6 fatty acids (PUFA n6) were significantly lower in SSc patients than in primary RP patients and controls (P < 0.001). TBARS were significantly increased in SSc patients compared with primary RP patients and controls (P < 0.001). Multiple regression analyses indicated that the reduced EM fluidity was partly due to its greater C:PL molar ratio, lower PUFA n6 content, and higher TBARS levels. EM fluidity was lower among patients with nailfold capillary loss (P < 0.001) and digital ischemic ulcers (P < 0.05). EM lipid peroxidation products were higher among patients with pulmonary involvement (bibasal pulmonary fibrosis [P < 0.05] and reduced levels of diffusing capacity for carbon monoxide [P < 0.001]) and among patients who were positive for anti-topoisomerase I antibodies (P < 0.05) or negative for anticentromere antibodies (P < 0.001). CONCLUSION: Our findings support the idea that oxidative injury occurs in SSc and that, through lipid peroxidation, it induces structural and functional changes of the EM that may contribute to the development of the microvascular abnormalities that are seen in the disease.

Erythrocyte Membrane↗