PubMed Health⌕ Search

Biomedical subjects

J Puig

Publications and source records attributed to J Puig.

At least 37 records · Page 2Linked to original sources

Chlorambucil-induced inappropriate antidiuresis in a man with chronic lymphocytic leukemia.

The syndrome of inappropriate antidiuretic hormone (SIADH) has been described in patients suffering from leukemia or lymphoma involving the central nervous system. Several alkylating agents have also been associated with this syndrome. We describe a patient with chronic lymphocytic leukemia, without evidence of central nervous system involvement, who suffered from SIADH presumably caused by small doses of chlorambucil.

Antineoplastic Agents, Alkylating↗

Cost-effectiveness and accuracy of the tests used in the differential diagnosis of Cushing's syndrome.

AIM: Establish the minimal biochemical and radiological examinations necessary and their cost-effectiveness to accurately diagnose the etiology of Cushing's syndrome (CS). MATERIAL AND METHODS: In 71 patients with CS followed between 1982 and 1997 biochemical studies (basal ACTH, 8 mg dexamethasone suppression test-HDST-, metyrapone stimulation test-MST-, or inferior petrosal sinus catheterization-IPSC-) and radiological investigations (abdominal CT scan, pituitary CT scan or MRI) were performed. Once pathology confirmed the diagnosis (48 pituitary Cushing's disease-CD, 17 adrenal neoplasms, 2 bilateral macronodular hyperplasia-BMH-, and 4 ectopic ACTH syndrome-ES-), the sensitivity, specificity, positive and negative predictive value of the different studies was calculated to establish the most accurate and cost-effective diagnostic protocol. RESULTS: In ACTH-independent CS (ACTH < or = 9 pg/ml; normal 9 to 54) a unilateral tumor was identified on abdominal CT scanning in 17, and BMH in 1; the other BMH had detectable ACTH (43.2 pg/ml). In ACTH-dependent CS, ACTH was > 9 pg/ml and IPSC (performed in 22) correctly identified 20 patients with CD and differentiated them from 2 with an ES (100% specificity and sensitivity). Pituitary MRI or CT did not disclose an adenoma in 41.7% of patients with CD, and was reported to exhibit a microadenoma in 2 of the 4 patients with ES. HDST and MST were of no additional use in the differentiation between CD and ES. CONCLUSIONS: Once CS is diagnosed low ACTH and an abdominal CT scan correctly identified all patients of adrenal origin. In ACTH-dependent CS IPSC was the best predictive test to differentiate CD from ES. BMH may behave as ACTH-dependent or independent. The other biochemical and radiological studies performed are not cost-effective and may even be misleading, and should not be routinely performed.

ACTH Syndrome, Ectopic↗

Modulation of staphylokinase-dependent plasminogen activation by mono- and divalent ions.

The effect of several ions (Cl-, Na+, K+, Ca2+) on the rate of plasminogen (Pg) activation by recombinant staphylokinase (rSTA) is reported. Both monovalent and divalent ions affect the rate at which Pg is activated by rSTA, in a concentration-dependent manner (range 0-100 mM). In almost all cases, a decrease of the initial velocity of activation was observed. Cl- showed the most striking inhibitory effect at low concentrations (64% at 10 mM). However, in the presence of a fibrin surface, this inhibition was attenuated to 38%. Surprisingly, 10 mM Ca2+ enhanced the Pg activation rate 21% when a polymerized fibrin matrix was present. These data support the idea that ions can modulate the rate of Pg activation through a mechanism that may be associated with changes in the molecular conformation of the zymogen. This effect is strongly dependent on the presence of a fibrin clot.

Enzyme Activation↗

[Screening for bone disease risk with clinical factors in women after physiologic menopause].

BACKGROUND: Densitometric screening for osteoporosis in postmenopausal women has not been demonstrated cost-effective. We have tried to identify clinical factors for screening previous to densitometry avoiding unnecessary explorations. PATIENTS AND METHODS SETTING: outpatient clinics of a menopausal unit in a 450-bed general hospital. Cross-sectional study, in two steps, of two groups of 140 and 284 women attending for physiological menopause. A clinical questionnaire, physical data and lumbar densitometry (Hologic QDR 1000) were obtained classifying the cases as "normal" or "low bone mass" (osteopenia or osteoporosis) according with the WHO criteria. In the first group a logistic regression analysis was done to identify predictive factors for abnormal densitometry, then validated in the second group. Sensitivity, specificity, predictive values (PV) and classification ability of clinical factors were analyzed. RESULTS: Four factors were independent predictors of abnormal densitometry: age > 51 (odds ratio [OR] = 6.64; 95% CI, 2.36-18.7); body weight < 70 kg (OR = 4.32; 95% CI, 1.71-10.09); years of fertility < 32 (OR = 3.77; 95% CI, 1.36-10.04), and number of live births > 2 (OR = 3.47; 95% CI, 1.27-9.53). Presence of one factor offers: sensitivity 91.9%; specificity 15%; positive PV 66.6%, and negative PV 50%, whereas the presence of two factors offers: sensitivity 62.7%; specificity 70%; positive PV 79.9%, and negative PV 50.3%. Clinical screening allows, when two factors are present, to avoid a 35.5% of densitometries and the false-negative cases represent 18%. CONCLUSIONS: Detection of bone-risk clinical factors (abnormal densitometry) yields a screening, previous to densitometry, that avoids at least one third of explorations in women with physiological menopause, improving the efficiency of the test.

Cross-Sectional Studies↗

Perforation of the pharynx caused by blunt external neck trauma.

We present two cases of a rare entity: pharyngeal perforation caused by blunt external neck trauma. In both cases the patients were asymptomatic for the first 24 h and the results of laryngoscopic study were negative, and it was only possible to demonstrate rupture through the radiologic findings. Early diagnosis is essential as delay in treatment increases morbidity and mortality.

Accidents↗

Hyperechoic liver nodules: characterization with proton fat-water chemical shift MR imaging.

PURPOSE: To evaluate proton fat-water chemical shift fast low-angle shot magnetic resonance (MR) imaging for differentiation of fat-containing hyperechoic liver nodules from hyperechoic liver nodules without a fatty component. MATERIALS AND METHODS: T1-weighted fast low-angle shot fat-water chemical shift gradient-echo MR imaging was performed in 96 patients without cirrhosis with 138 hyperechoic liver nodules. In-phase and opposed-phase breath-hold images were acquired. The percentage of signal intensity variation between in-phase and opposed-phase images and the spleen-to-lesion contrast ratio were used to differentiate liver nodules. RESULTS: Chemical shift MR images showed fat in 15 (11%) hyperechoic nodules (two angiomyolipomas and 13 nodular fatty infiltrations of the liver). The mean percentage of signal intensity variation between in-phase and opposed-phase images was 156% (standard error, 43.5%) in nodules with fat and -0.16% (standard error, 0.96%) in nodules without fat (P = .003). Spleen-to-lesion contrast was similar on in- and opposed-phase images in lesions without fat (mean difference, -0.0107; standard error, 0.012), whereas the mean difference in fat-containing nodules was 0.805 (standard error, 0.225; P = .003). The area under the receiver operating characteristic curve was 0.97 for signal intensity variation. CONCLUSION: Hyperechogenicity in certain liver nodules is caused by fat. Chemical shift MR imaging allows accurate differentiation between these and other hyperechoic lesions with no fat component.

Adipose Tissue↗

Modelling the kinetics of antigen-antibody reactions at particle enhanced optical immunoassays.

Functionalized latexes coated by antibodies are used in diagnostic tests for the detection of antigens in biological fluids. A simple kinetic model is presented which is related to the optical monitoring of the formation of specific complexes between antigen and antibody amplified by latex beads. The antibodies are chemically coupled onto chloromethylstyrene (CMST) particles. The kinetic model is able to describe the immunoprecipitin curves of immunolatex beads. The number of fitting parameters is relatively reduced (only three), and the meaning of these parameters can be interpreted in terms of the chemical equilibrium constant, the percentage of active IgG on the latex beads, and optical response. The model explains very well the optical response of immunolatex prepared by covalent coupling of antibodies on polymer carriers.

Animals↗

[Current perspectives in screening for cardiac diseases which most frequently cause sudden death during the practice of a sports activity].

Sudden death during sports activities is extremely rare in athletes and sportsmen. Its occurrence was calculated at 0.77 to 13 deaths per 100,000 sportsmen/year. The most frequent causes were coronary heart disease, coronary muscular bridges, congenital coronary artery anomalies, subarachnoid hemorrhage, hypertrophic cardiomyopathy, arrhythmogenic right ventricular dysplasia, Marfan syndrome, aortic coarctation, myocarditis, pulmonary embolism, aortic stenosis, mitral valve prolapse and WPW syndrome. Clinical examination nearly identifies all cases of aortic stenosis, mitral valve prolapse with regurgitation, and aortic coarctation but misses the majority of cases of hypertrophic cardiomyopathy and coronary artery diseases. The use of Chest x-rays, ECG, Stress Test and Echocardiogram will provide the identification of most cases with increased risk of death. Although costs are not limited for professional athletes, this strategy does not totally overcome the problem because diagnostic errors are frequent (false positives and false negatives). Therefore it is important to admit the failure of these screening procedures and the necessity to adapt the strategy to cost-efficiency and time-efficiency in this population.

Aortic Diseases↗

Acute effects of ethanol on mineral metabolism and trabecular bone in Sprague-Dawley rats.

In order to assess the effects of acute ethanol intoxication on bone, 45 female Sprague-Dawley rats were studied. Five rats were sacrificed at baseline. The remainder received either ethanol (2 g/kg of body weight) intraperitoneally or isotonic saline. Rats were sacrificed in groups of 10 (5 intoxicated and 5 placebo) at 1, 4, 8, and 24 hours after injection. At the time of sacrifice, a blood sample was obtained and the 4th vertebra was excised for histomorphometric analysis of undecalcified bone. Effect of ethanol was assessed by an analysis of variance test using a Scheffé procedure. In ethanol-treated rats we observed (mean +/- SD, ethanol versus controls, maximum difference point, P value) a significant decrease in osteiod surface with osteoblasts (42.86 +/- 15.61% versus 64.57 +/- 6.24%, P < 0.05); osteoclast number (0.05 +/- 0.02 n/mm2 versus 0.17 +/- 0.09 n/nm2, P < 0.05), and osteocalcin (36.9 +/- 2.21 ng/ml versus 45.8 +/- 5.1 ng/ml, P < 0.05). Osteoclast surface was initially reduced (0.129 +/- 0.09% versus 0.425 +/- 0. 26%, P < 0.01) but showed a subsequent increase (0.765 +/- 0.24% versus 0.226 +/- 0.17%, P < 0.01) attributable to alcohol. There was also a significant decrease in serum Ca (8.51 +/- 0.23 mg/dl versus 9.10 +/- 0.29 mg/dl, P < 0.01) and parathyroid hormone values (23.51 +/- 5.72 pg/ml versus 76.39 +/- 11.66 pg/ml, P < 0.001). We conclude that acute alcohol intoxication in rats induces early striking changes in bone histology and analytical parameters, not completely reversed after 24 hours. These data are consistent with a toxic effect induced by alcohol on bone.

Acid Phosphatase↗

Circadian heart rate variability rhythm in shift workers.

The objective of this study was to assess the influence of day-night cycle and sleep-awake period on the circadian pattern of heart rate variability (HRV). Twelve male oil refinery security shift workers, aged 39 +/- 7 years, were studied with 24-hour Holter monitor recordings during morning and night work periods. Hourly HRV parameters in the time and frequency domains were evaluated. For both shifts, all HRV parameters during awake or work periods were found not to be statistically different. In both day and night work shifts, the very low frequency and high-frequency components of HRV and the proportion of differences in successive R-R intervals greater than 50 ms increased during the sleep period, while the low frequency/high frequency ratio decreased. The low-frequency component in absolute units and the SD of the R-R interval did not show any variation in either shifts for the different periods. These results suggest that the circadian pattern of HRV seems to be predominantly related to sleep (supine) and wakefulness (standing) and remains independent of night-day cycle.

Adult↗

Cloning, expression and purification of recombinant streptokinase: partial characterization of the protein expressed in Escherichia coli.

We cloned the streptokinase (STK) gene of Streptococcus equisimilis in an expression vector of Escherichia coli to overexpress the profibrinolytic protein under the control of a tac promoter. Almost all the recombinant STK was exported to the periplasmic space and recovered after gentle lysozyme digestion of induced cells. The periplasmic fraction was chromatographed on DEAE Sepharose followed by chromatography on phenyl-agarose. Active proteins eluted between 4.5 and 0% ammonium sulfate, when a linear gradient was applied. Three major STK derivatives of 47.5 kDa, 45 kDa and 32 kDa were detected by Western blot analysis with a polyclonal antibody. The 32-kDa protein formed a complex with human plasminogen but did not exhibit Glu-plasminogen activator activity, as revealed by a zymographic assay, whereas the 45-kDa protein showed a K(m) = 0.70 microM and kcat = 0.82 s-1, when assayed with a chromogen-coupled substrate. These results suggest that these proteins are putative fragments of STK, possibly derived from partial degradation during the export pathway or the purification steps. The 47.5-kDa band corresponded to the native STK, as revealed by peptide sequencing.

Cloning, Molecular↗

[Clinical, psychological and biological variables in a group of 108 adolescent patients with anorexia nervosa].

BACKGROUND: To assess the clinical and psychological characteristics, hormonal changes derived from malnutrition and the prognostic factors in an adolescent group of patients with anorexia nervosa. PATIENTS AND METHODS: In this retrospective study specific case-history medical record for this disorder was used first with the parents and later with the patients. Depression questionnaires (BDI or CDI) and eating disorders questionnaires (EAT and CIMEC) were also administered, and hormonal tests were carried out. RESULTS: 98 out of 108 patients (90.7%) were females. Mean age was 15 years, 23 patients (21.1%) showed major depressive disorders or obsessive-compulsive disorders besides anorexia nervosa. The duration of the disorder was 12.0 +/- 9.0 months. The age at onset of the disorder was 15.1 +/- 1.5 (10-17 years), and the percentage of weight loss ranged between 15.53%. In relation to the hormonal findings the low levels of T3, insulin, somatomedin, prolactin, LH and 17 B estradiol were shown up. There were no differences between inpatients and outpatients in relation to the age of onset of the disorder onset, duration of the disorder, percentage of weight loss, psychological variables or applied hormonal findings. There were differences in relation to the used psychometric tests, which differentiated between patients with a good and bad outcome. CONCLUSIONS: Major depressive disorders and obsessive-compulsive disorders are the most frequent comorbid psychiatric disorders in the anorexia nervosa. The age at onset of the disorder, duration of the disorder, percentage of weight loss and hormonal changes do not seem to influence in outcome, whereas initial affective and eating symptomatology tend to predict disorder outcome.

Adolescent↗

Heart rate variability in brain death.

The sensitivity and specificity of heart rate variability (HRV) in the corroboration of brain death diagnosis in patients with acute traumatic intracranial lesions was evaluated in 20 patients with clinical criteria of brain death, nine patients in deep coma (Glasgow scale < 7) and 18 normal controls, all age matched. The electrocardiogram was sampled at 650 Hz and several parameters of HRV were calculated, in both time and frequency domains. The HRV parameters were significantly lower in the brain death group compared with the deep coma group. Linear discriminant analysis between brain death and deep coma patients was performed on a data set made of nine randomly selected patients with clinical criteria of brain death and nine patients in deep coma. Cross-validation was performed on the remaining 11 patients with clinical criteria of brain death. All patients in the data set were correctly classified (sensitivity and specificity of 100%). All patients in the cross-validation set were correctly classified (sensitivity of 100%). Further studies are necessary to evaluate the specificity of the method in the independent set of deep coma patients and in the follow-up of comatose and vegetative patients to identify irreversibility of HRV. Nevertheless, these results suggest that HRV analysis constitutes a fully sensitive and specific method for assessing brain death in potential organ donors with acute traumatic lesions of the brain. This fast, quantitative and bedside method seems very promising for the early confirmation of brain death, which is an important factor for the success of transplantation procedures and could have a high predictive value of brain death in comatose patients with brain injuries without fully diagnostic criteria.

Adolescent↗

[Neurocardiogenic syncope: its pathogenesis, diagnosis and treatment].

Neurocardiogenic syncope seems to be the most common cause of syncope. It is believed to be triggered by paradoxical autonomic reflexes, beginning in the ventricular mechanoreceptors of the heart, modulated by the brain stem and terminating in the autonomic efferent pathways (parasympathetic stimulation with bradycardia or asystole and sympathetic inhibition with severe hypotension). Tilt test has been used recently, as a safety and effective tool to identify subjects prone to syncope. Although the pathophysiology of this syndrome is not completely understood, pharmacological therapeutics seems very effective in resolving symptoms.

Autonomic Nervous System↗