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J Serra

Publications and source records attributed to J Serra.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Can the Brucellacapt test be substituted for the Coombs test in the diagnosis of human brucellosis?].

BACKGROUND: Throughout this work we have studied the capacity of Brucellacapt test to replace Coombs test in the serological diagnosis of human brucellosis. METHODS: A total of 66 initial sera from patients with diagnostic of brucellosis were studied. The patients were divided in two groups: 42 patients showing a primo-infection (group1), and 24 patients with a previous case of brucellosis (group 2). As a controls, for the group 1 we have used 100 sera from healthy donors, and for group 2, 28 sera from people that have had clinical brucellosis but actually are in good health. All serum samples were tested in either Coombs and Brucellacapt tests. The diagnostic yield was calculated using ROC (receiver-operating characteristic) plots.Moreover, the results obtained in Coombs and Brucellacapt tests with 397 serum samples from 66 patients with brucellosis were compare with a non-parametric method. RESULTS: The sensibility and specificity for group1 were respectively 1 and 0.98 for Coombs and, 1 and 0.95 for Brucellacapt tests. For group 2, the results in Coombs test were 1 and 0.80, and in Brucellacapt test 0.95 and 0.74. In this second group, the area under the ROC plot was 0.950 for Coombs and 0.904 for Brucellacapt tests. Non statistical differences were observed comparing both serological tests using the Wilcoxon method (Z= -0.213; p=0.8). CONCLUSIONS: Brucellacapt and Coombs tests yield similar diagnostic results in the follow-up of serological samples from patients with brucellosis, and its should consider as interchangeables.

Brucellosis↗
PubMed2001

Impaired transit and tolerance of intestinal gas in the irritable bowel syndrome.

BACKGROUND: Patients with irritable bowel syndrome (IBS) frequently complain of excessive gas but their fasting volume of intestinal gas is apparently normal. We hypothesised that the pathophysiological mechanism involved may be impairment of intestinal gas transit. AIM: To investigate intestinal gas transit and tolerance in IBS patients compared with healthy subjects. METHODS: A gas mixture (N(2), O(2), and CO(2) in venous proportions) was infused into the jejunum of 20 patients with IBS and 20 healthy controls at 12 ml/min for four hours. Gas evacuation, initially flatus from the anus (two hours) and then intrarectally (two hours), was continuously recorded. Symptom perception (0-6 scale) and abdominal distension were measured at 10 minute intervals. RESULTS: After two hours of external gas (flatus) collection, 18 of 20 IBS patients had developed gas retention (>400 ml), increased gastrointestinal symptoms (score >3), or abdominal distension (>3 mm girth increment) compared with only four of 20 control subjects. During intrarectal gas collection, 13 of 17 patients still exhibited abnormal responses. CONCLUSION: A large proportion of patients with IBS can be shown to have impaired transit and tolerance of intestinal gas loads. This anomaly may represent a possible mechanism of IBS symptoms, specifically pain and bloating.

Abdomen↗
PubMed2001

Mechanisms of intestinal gas retention in humans: impaired propulsion versus obstructed evacuation.

To explore the clinical role of intestinal gas dynamics, we investigated two potential mechanisms of gas retention, defective propulsion and obstructed evacuation. In healthy subjects, a gas mixture was continuously infused into the jejunum (4 ml/min) 1) during a 2-h control period of spontaneous gas evacuation and 2) during a 2-h test period either with impaired gut propulsion caused by intravenous glucagon (n = 6) or with obstructed (self-restrained) anal evacuation (n = 10) while anal gas evacuation, symptom perception (0-6 scale), and abdominal girth were measured. Impaired gut propulsion and obstructed evacuation produced similar gas retention (558 +/- 68 ml and 407 +/- 85 ml, respectively, vs. 96 +/- 58 ml control; P < 0.05 for both) and abdominal distension (8 +/- 3 mm and 6 +/- 3 mm, respectively, vs. 1 +/- 1 mm control; P < 0.05 for both). However, obstructed evacuation increased symptom perception (2.3 +/- 0.6 score change; P < 0.05), whereas gas retention in the glucagon-induced hypotonic gut was virtually unperceived (-0.4 +/- 0.7 score change; not significant). In conclusion, the perception of intestinal gas accumulation depends on the mechanism of retention.

Adult↗
PubMed2001

Evaluation of an automated method for the quantification of von Willebrand factor antigen. Its application in the study of vascular dysfunction.

BACKGROUND AND OBJECTIVES: Abnormally high levels of von Willebrand factor (VWF) have been described as a response to physiologic and chronic alterations. It is therefore of great interest to have sensitive, accurate, fast and easy to use assays to quantify VWF. The aim of this study was to evaluate the performance characteristics of the immunoturbidimetric assay IL Test VWF:Ag and the use of this determination in the study of vascular dysfunction. DESIGN AND METHODS: The reproducibility, accuracy and linearity of the method were determined. A method comparison study was performed using an ELISA as the reference test. The assay reference range and its age-dependence were established. To evaluate the utility of the assay in vascular dysfunction, a cohort of 30 type 1 diabetes mellitus (DM) patients were analyzed, 11 of whom showed microvascular complications. RESULTS: The linearity range found was 10-150 IU/dL. Reported values above 150 IU/dL should be diluted and reanalyzed, expanding the range up to 600 IU/dL. The coefficients of variation were below 5% and inaccuracies below +/-15% within the linearity range. The comparison with the reference ELISA showed a good correlation coefficient (r = 0.985, VWF values from 5-680 IU/dl). The reference range was found to be 40.8 - 158.1 IU/dL. Significant differences between the DM type 1 patients with microvascular complications and a sex-age matched control group were observed. This difference was not observed for the DM patients not showing vascular alterations. INTERPRETATION AND CONCLUSIONS: The method is reproducible, accurate and linear. The assay correlates well with the reference ELISA. There is a relationship between patients showing microvascular diabetic complications and high levels of VWF:Ag. The assay is easy to perform, fully automated, and suitable for analyzing a small number of samples.

Adolescent↗
PubMed2000

Prepulse inhibition of the blink reflex by laser stimuli in normal humans.

The subcortical integrative effects of laser-induced activation of pain ascending tracts were examined in 11 healthy volunteers, aged 22-52 years. Subjects underwent either CO2 laser stimulation at the dorsum of the hand, electrical stimulation of digital nerves at the 3rd finger, or mechanical taps to the first dorsal interosseous space, preceding a blink reflex elicited by a supraorbital nerve electrical stimulus. The percentage inhibition induced in the R2 response of the blink reflex was similar for the three different stimulus modalities, but occurred at a different time interval. Compared to control trials, the R2 response of the test trials was a mean of 23.1% at the interval of 250 ms with laser stimuli, 17.4% at the interval of 100 ms with electrical stimuli to the 3rd finger, and 20.6% at the interval of 90 ms with a mechanical tap to the 1st interosseous space. Activation of pain receptors induces prepulse inhibition of the blink reflex at a delay corresponding to a slowly conducting pathway. The percentage inhibition is similar to that observed with other somatosensory inputs.

Adult↗
PubMed2000

Value of sonography in the assessment of space-occupying lesions of the anterior nasal fossa.

PURPOSE: This study was conducted to define the gray-scale, color, and power Doppler sonographic appearances and spectral analysis patterns of anterior nasal masses. METHODS: Eight patients with anteriorly located nasal masses were referred to our hospital for CT of the paranasal sinuses. Subsequently, they were examined with a high-frequency linear-array ultrasound transducer. We performed gray-scale sonography and color and power Doppler imaging. RESULTS: Five masses were nasal hemangiomas. The three remaining masses were a submucosal glandular cyst, a nasolabial cyst, and tuberculum septi hypertrophy. Three of the hemangiomas were histopathologically confirmed. Sonography identified the anatomic origin of all 8 lesions. On color and power Doppler imaging, the 5 hemangiomas exhibited intense vascularity that decreased with compression. Spectral analysis demonstrated arterial and venous flow within the hemangiomas, with resistance indices of 0.60-0.66 and peak systolic velocities of 6.4-18.4 cm/second. The other 3 lesions were avascular or had vascularity only at the periphery. CONCLUSIONS: Anterior nasal fossa tumors can frequently be diagnosed by clinical examination, but specific sonographic and Doppler patterns can help to establish the anatomic origin, the local extension, and the correct diagnosis in indeterminate cases, obviating other diagnostic imaging or surgical procedures.

Adult↗
PubMed2000

[Seroepidemiological study of brucellosis in a rural endemic area].

BACKGROUND: This study investigated the prevalence of Brucella spp. antibodies in the general population in the Health Area of Tremp (Region of Pallars Jussà, Lleida). It also identified the risk factors with the presence of these. PATIENTS AND METHODS: A total of 346 (191 men and 155 women) were studied. Information about the sex, age, location, the personal and familiar antecedents of brucellosis, occupational risk, contact with the animals and the consumption of non-hygienic dairy products was recorded. The estimation of the seroprevalence was carried out by the ELISA IgG test. The association of independent variables with the presence of antibodies was assessed by the Coombs to Brucella and the ELISA IgG tests. It was assessed by using the calculation of the analysis variance. RESULTS: The personal antecedents, the contact with the animals and the occupational risk all showed a statistically significant relation (p < 0.05) with the Coombs and ELISA IgG tests. The familiar antecedents showed a significant relation with the ELISA IgG. The consumption of dairy products and the location showed no statistically significant relation. A seroprevalence was obtained among the researched population of 11.9%, the maximum occurred in Isona surgery (25.6%) and the minimum in Tremp (9.8%). CONCLUSIONS: The seroprevalence is high and the epidemiological profile associated with the fact of being seropositive is associated with the profession of the study subject and it coincides with de infection mechanisms present in the area.

Adolescent↗
PubMed2000

Quantification of D-dimer using a new fully automated assay: its application for the diagnosis of deep vein thrombosis.

BACKGROUND AND OBJECTIVE: A D-dimer assay can be helpful to rule out thromboembolism provided it is sensitive, reliable, fast and easy to perform. Tests based on the ELISA methodology have a high diagnostic sensitivity, and are therefore adequate for excluding deep venous thrombosis (DVT). The drawbacks are their long assay times, unsuitability to be run on single samples and cost. New methods have been developed, based either on the same principle, by immunofiltration or by microlatex immunoturbidimetric assays which seem to reach the high sensitivity and negative predictive value (NPV) required, but allowing fast and quantitative single sample analysis. The aim of this work was to evaluate one rapid test, a fully automated quantitative assay (IL Test D-dimer, run on an ACL 7000 coagulation analyzer, Instrumentation Laboratory). DESIGN AND METHODS: We compared the diagnostic value of IL Test for DVT with that of an ELISA (Dimertest Gold EIA Agen Biomedical Limited, Acacia Ridge, Australia). Eighty-six patients (43 men, 43 women, mean age: 61 years) showing DVT symptoms formed the population for this non-randomized controlled trial in a referral center. The diagnosis of DVT based on the clinical history, was confirmed by serial compression ultrasonography (CUS) with Doppler flow in 62 patients. RESULTS: The IL Test D-dimer proved to be rapid, automated and well suited for individual tests with a good reproducibility in three control plasmas with different concentrations of D-dimer (coefficient of variation range 0.54-3. 87%). Its performance was comparable to that of the Dimertest Gold EIA, as indicated by the areas under the receiver operating characteristic curves (Dimertest Gold EIA 0.748; IL Test D-dimer 0.70). On the basis of kappa coefficients, there was a good concordance between the Dimertest Gold EIA and IL Test D-dimer when the receiver operating characteristic (ROC) curves suggested cut-offs were used. The sensitivity (98.3%) and NPV (88.9%) shown by IL Test D-dimer are comparable or even better than those obtained for EIA (95%, 80%, respectively). INTERPRETATION AND CONCLUSIONS: This study shows that the new method can be included in prospective clinical trials to test the utility of D-dimer measurement in combination with other non-invasive diagnostic procedures in the management of DVT diagnosis.

Adolescent↗
PubMed1999

Activity-dependent slowing of conduction differentiates functional subtypes of C fibres innervating human skin.

1. The effects of impulse activity on conduction in cutaneous C fibres have been examined in 46 microneurographic recordings from 11 normal subjects and 11 diabetic patients with normal nerve conduction. A tungsten microelectrode was inserted into a cutaneous nerve, usually the superficial peroneal close to the ankle, and intraneural microstimulation was used to identify an area of skin innervated. Three minute trains of 0.25 ms stimuli at 1, 2 and 4 Hz were then delivered to the surface of the skin, separated by intervals of 6 min with stimulation at 0.25 Hz. Slowing and block of conduction were measured from the nerve responses for up to seven C units per stimulation sequence. 2. Three types of C unit were distinguished by their responses to repetitive stimulation: type 1 units slowed progressively during the 3 min trains; slowing of type 2 units reached a plateau within 1 min; while type 3 units hardly slowed at all. Data from normal and diabetic subjects did not differ and were pooled. After 3 min at 2 Hz, the percentage increases in latency were for type 1, 28.3 +/- 9.7 (n = 63 units, mean +/- s.d.); for type 2, 5.2 +/- 1.6 (n = 14); and for type 3, 0.8 +/- 0.5 (n = 5), with no overlap. After 3 min at 4 Hz, 58 % of type 1 units (but no type 2 or 3 units) blocked intermittently. Recovery of latency after stimulation was faster for type 2 than for type 1 units, but conduction velocities of the three types were similar. 3. Type 1 units were identified as nociceptors and 7 type 2 units were identified as 'cold' fibres, activated by non-noxious cold, with no overlap in modality. None of the units tested was activated by weak mechanical stimuli or reflex sympathetic activation. 4. Spike waveforms were averaged for 18 type 1, 10 type 2 and 6 type 3 units. All units had predominantly triphasic action potentials with a major negative peak, but those of type 3 units were on average both smaller and briefer than those of type 1 and type 2 units. 5. It is concluded that repetitive electrical stimulation reliably differentiates nociceptive from cold-specific C fibres innervating human hairy skin, as has previously been shown for the rat. Cold fibres can propagate impulses continuously at much higher rates than nociceptive fibres. The nature of the type 3 units is unclear.

Adult↗
PubMed1999

Central motor conduction time in patients with multifocal motor conduction block.

The finding of conduction block (CB) within short consecutive segments along a motor nerve is a key feature of multifocal motor neuropathy (MMN). Despite their different pathogenesis, this may be the only clinical difference between some cases of MMN and the pure spinal muscular atrophy form of motor neuron disease (MND). In 12 patients with distal atrophy and fasciculations and electrophysiological evidence of CBs in the upper limbs, we measured the peripheral and central motor conduction times (PMCT and CMCT) to hand muscles. We reasoned that patients with MMN should show an abnormally prolonged PMCT with normal CMCT, whereas an increased CMCT would suggest MND. All patients had delayed F-wave latency and increased PMCT. Three patients had increased CMCT. Follow-up showed little clinical and electrophysiological change in 7 of the 9 patients with normal CMCT, and a progressive motor deficit leading ultimately to death in 1 of the 3 patients with increased CMCT. This patient's electrophysiological follow-up showed a significant decrement of the compound motor action potential to both proximal and distal stimulation points, with disappearance of earlier CBs. Autopsy revealed loss of anterior horn cells and axons of the ventral root, and degeneration of large myelinated fibers. We conclude that determining the CMCT may help in differentiating MND from MMN. Persistence of a stable clinical picture over a span of at least 1 year and lack of electrophysiological signs of involvement of upper motor neurons should both be required before establishing the diagnosis of MMN even with electrophysiological evidence of CB.

Adult↗
PubMed1999

Prevalence of diabetes in Catalonia (Spain): an oral glucose tolerance test-based population study.

The goal of this study was to investigate the prevalence of diabetes mellitus and impaired glucose tolerance in the adult population of Catalonia and study their association with obesity, central obesity, hypertension and smoking habit. A random sample of 3839 subjects aged 30-89 years participated in this cross-sectional study: 2214 subjects underwent a health examination with oral glucose tolerance test (OGTT) and 1625 were interviewed by phone. Diabetes prevalence (known and unknown) in the 30-89-year-old population was 10.3%, (95% CI: 9.1-11.6). In this age group, the prevalence rates of known diabetes, unknown diabetes and impaired glucose tolerance were 6.4, 3.9 and 11.9% in men and 6.9, 3.4 and 11.9% in women. The age adjusted prevalence to the world population for the 30-64-year-old age group was 6.1% (7.1% in men and 5.2% in women).The factors significantly associated with diabetes were age, obesity, hypertension and family history of diabetes. The high ratio of previously known diabetic cases to newly discovered ones, specially in the oldest age group, suggests good levels of awareness and medical services. The prevalence in Catalonia is similar to that observed in other Mediterranean countries.

Adult↗
PubMed1999

Six-month outcome in unstable angina patients without previous myocardial infarction according to the use of tertiary cardiologic resources. RESCATE Investigators. Recursos Empleados en el Síndrome Coronario Agudo y Tiempos de Espera.

OBJECTIVES: The study assessed whether varying accessibility of patients with unstable angina (UA) to coronary angiography and revascularization determined differing usages and outcomes. BACKGROUND: The appropriate use rate of coronary angiography and revascularization procedures in UA remains to be established. METHODS: A total of 791 consecutive patients with UA without previous acute myocardial infarction (AMI) admitted to four reference teaching hospitals (one with tertiary facilities) were followed for six months. End points were six-month mortality and readmission for AMI, UA, heart failure, or severe ventricular arrhythmias. RESULTS: Patients admitted to the tertiary hospital were 3.27 (95% confidence interval [CI] 2.32 to 4.62) times more likely to undergo coronary angiography after adjustment for comorbidity and severity than were those admitted to nontertiary facilities (overall six-month use rates 70.1% and 48.3%, respectively). Revascularization procedures were performed in 36.2% of patients in the tertiary hospital and 24.6% in the others (p = 0.0007); adjusted relative risk (RR) 2.37 (95% CI 1.55 to 3.63). Median delay for urgent coronary angiography was shorter in the tertiary hospital (24 h vs. 4 days, p < 0.0002). Six-month mortality and readmission rates were similar in tertiary and nontertiary hospitals: 3.9% versus 5.3% and 16.9% versus 21.2%, respectively. Adjusted RR of death or readmission for the nontertiary hospitals was 1.23 (95% CI 0.57 to 2.67). CONCLUSIONS: The use of coronary angiography and revascularization procedures in UA patients with no previous AMI is higher in tertiary than in nontertiary hospitals, but the more selective use of these procedures in nontertiary centers does not imply worse outcome.

Aged↗
PubMed1999

Overview of neuropathic pain syndromes.

Patients with peripheral nerve injury often express a variety of positive sensory symptoms. Description of these symptoms can range from "painful" to "painless" to "painless but very unpleasant." Although it is widely accepted that both peripheral and central processes may play a role in the pathophysiology of these symptoms, peripheral mechanisms in particular are often overlooked. Sensitization of nociceptor unit receptors, spontaneous or stimuli-induced ectopic impulse generation, "multiplication" of impulses, and ephaptic transmission are pathophysiologic mechanisms resolved at the peripheral level that may explain the patient's symptomatology. It is important to reach an accurate diagnosis and to investigate the pathophysiology of every individual symptom. Only when this has been achieved is it possible to plan adequate symptom-oriented therapeutic strategies. In the future, therapy will be more symptom-oriented than illness-oriented, and treatment options will most likely be tailored to fit the specific constellation of symptoms expressed by a particular patient.

Humans↗
PubMed1999

A new transthyretin variant--ATTR Arg104Cys.

We report the genetic characterization of a transthyretin variant previously detected by mutation scanning employing single strand conformation polymorphism analysis in patients with peripheral neuropathies. A substitution of a thymine for cytosine resulting in the replacement of an arginine with cysteine at position 104 of the polypeptide chain was found both by DNA sequencing and restriction fragment length polymorphism analysis. The propositus presented a sensory axonal neuropathy, no neurological abnormalities in the upper limbs nor autonomic involvement. No evidence for amyloid deposition was found in either muscle and nerve biopsies. There was no history of amyloidosis in the family. This mutation might be rare in the population and future cases of the mutation will ascertain a relationship with disease.

Aged↗
PubMed1999

[Stapedectomy versus stapedotomy. Our experience].

Otosclerosis surgery has seen three well-differentiated stages of development: a) SHC fenestration; b) stapes mobilization, and c) platinectomy, a procedure introduced in 1960 by Shea. Since then, only one variation has been proposed: platinotomy. After a comparative study of platinectomy versus platinotomy, we, like other authors, concluded that platinotomy was a better technique because of the ease of execution and good functional results.

Adolescent↗
PubMed1999

[Should all patients with ventricular pre-excitation of the Wolff-Parkinson-White syndrome type undergo catheter ablation?].

The authors make a concise review concerning clinical, electrocardiographic and electrophysiologic risk stratification in Wolff-Parkinson-White syndrome and present the results of radiofrequency catheter ablation of atrioventricular accessory pathways. The low sensitivity of electrophysiologic criteria for the identification of a high risk profile limits their use in asymptomatic patients with a low incidence of sudden death. The greater risk of ventricular fibrillation in symptomatic patients makes radiofrequency catheter ablation the treatment of choice for these patients. Therefore, the authors do not recommend an electrophysiologic risk stratification in Wolff-Parkinson-White syndrome, but emphasize that catheter ablation should be performed in all symptomatic patients.

Adolescent↗