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Biomedical subjects

M R Sala

Publications and source records attributed to M R Sala.

At least 19 recordsLinked to original sources

Peripheral tissue release of interleukin-6 in patients with chronic kidney diseases: effects of end-stage renal disease and microinflammatory state.

To examine if uremia influences muscle interleukin-6 (IL-6) metabolism we studied the exchange of IL-6 across the forearm in 16 patients with chronic kidney disease (CKD) (stages 3 and 4), in 15 hemodialysis (HD)-treated end-stage renal disease (ESRD) patients (n=15), and in six healthy controls. In addition, we performed an analysis of both IL-6 protein and IL-6 mRNA expression in muscle of CKD (stage 4) patients showing evidence of inflammation and in controls. A release of IL-6 from the forearm was observed in patients with elevated IL-6 plasma levels. Arterial IL-6 was directly related to released IL-6 (r=0.69; P<0.004) in HD patients. Both IL-6 protein and IL-6 mRNA expression were increased in muscle of inflamed CKD patients vs controls (P<0.05). Although muscle net protein balance was similar in all patients, it was significantly more negative in HD patients with high than in those with low IL-6 plasma levels (P<0.05). In addition, net protein balance was related to the forearm release of IL-6 in HD patients only (r=0.47; P<0.038). These data demonstrate that IL-6 expression is upregulated in muscle, and that muscle tissue, by releasing this cytokine, may contribute to the inflammatory response in HD patients. The release of IL-6 from peripheral tissues is associated with an increase in muscle protein loss in HD patients, suggesting that muscle release of IL-6 is linked to protein catabolism in these patients. The release of IL-6 from peripheral tissues may act as a signal for the inflammatory response and contribute to functional dysregulation in uremia.

Aged↗

Waterborne epidemic outbreak of Shigella sonnei gastroenteritis in Santa Maria de Palautordera, Catalonia, Spain.

In August 2002 an outbreak of Shigella sonnei infection occurred in a Spanish town of 6343 inhabitants. In total, 756 people developed acute gastroenteritis and 181 cases were shigella-confirmed. The peak incidence was during 5-6 August 2002. The estimated primary attack rate was 9.97%; the attack rate for secondary cases was 38%. The <15 years ago group was most affected (16.49%). The town and its surroundings were served by two water systems, A and B. The cases had consumed water provided by system A (attack rate 164 cases/1000 population). Microbiological analysis of water from system A did not show the presence of coliform bacteria or shigella. This shigellosis outbreak was the largest reported in Spain. The impact of the epidemic was probably greater than the incidence detected.

Adolescent↗

An outbreak of food poisoning due to a genogroup I norovirus.

Norovirus infection is associated with approximately 90% of epidemic non-bacterial acute gastroenteritis. The objective of this study is to describe an outbreak of norovirus genogroup I gastroenteritis which affected workers in a hospital and was attributed to food prepared by an infected food handler. Forty cases were detected, of whom 80% were interviewed. The index case was the cook employed in the hospital cafeteria. The following symptoms were observed: abdominal pain in 90.6%, vomiting in 71.9%, diarrhoea in 71.9%, general indisposition in 62.5%, headaches in 53.1% and fever in 32.4% of cases. The initial symptoms were abdominal pain in 37% and vomiting in 28%. Of the 14 samples analysed by RT-PCR, 12 (86%) were positive for a genogroup I norovirus. After sequencing the strain was identified as genotype Desert Shield. Many of the foodstuffs consumed were made by hand, favouring transmission from the index case to the cafeteria users.

Adult↗

Muscle protein turnover in chronic renal failure patients with metabolic acidosis or normal acid-base balance.

It is currently unknown if metabolic acidosis has any effect on muscle protein metabolism in patients with chronic renal failure (CRF). To address this question, muscle protein turnover was studied in patients with CRF and controls in the postabsorptive state by using the forearm perfusion method together with the 3H-phenylalanine kinetics. Nine patients were acidotic ([HCO-3]a = 20 +/- 0.5 mEq/l) whereas 4 patients had a normal acid-base balance ([HCO-3]a = 25 +/- 0.3 mEq/l). In patients with metabolic acidosis the rates of phenylalanine appearance and disposal from the forearm were increased as compared to controls. Phenylalanine net balance, i.e. net proteolysis, was only slightly higher than in controls. In patients under a normal acid-base balance both rates of appearance and disposal of phenylalanine as well as phenylalanine net balance were similar to controls. These preliminary data suggest that metabolic acidosis can enhance the rate of muscle protein degradation in patients with CRF.

Acidosis↗

Skeletal muscle protein synthesis and degradation in patients with chronic renal failure.

Muscle protein turnover and amino acid (AA) exchange across the forearm were studied in nine postabsorptive patients with chronic renal failure (CRF) under unrestricted calorie-protein diets and eight controls by using the arterio-venous difference technique associated with the 3H-phenylalanine kinetics. In patients with CRF: (1) the rate of appearance (Ra) of phenylalanine (Phe) from the forearm, reflecting proteolysis, was 27% increased in comparison with controls (P < 0.01). Also the rate of disposal (Rd) of Phe, reflecting protein synthesis, was increased in patients (P < 0.01). As a consequence of these counterbalanced alterations, net balance of Phe across the forearm, that is, net proteolysis, was not changed. (2) The release of total AA from the forearm was not different from controls. Valine and ketoisocaproate release was reduced (P < 0.05). Serine uptake was not detectable. (3) Net proteolysis and the Rd/Ra ratio were inversely and directly, respectively, related to arterial [HCO3-] (P < 0.02 and P < 0.03, respectively). (4) Moreover, net proteolysis and Phe Rd/Ra ratio were directly and inversely, respectively, correlated with plasma cortisol (P < 0.01 and < 0.005, respectively). Plasma cortisol was in the normal range and inversely related to arterial [HCO3-] (P < 0.02). (5) While in controls phenylalanine appearance from the forearm was inversely related to insulin levels, no correlation was found in patients. In conclusion, in patient with CRF, forearm Phe kinetics indicate the existence of an increased muscle protein turnover. Changes in protein synthesis and degradation are well balanced and net proteolysis is not augmented.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Erythropoietin treatment and amino acid metabolism in hemodialysis patients.

A previous report suggests that treatment with recombinant human erythropoietin (rH-EPO) significantly improves many abnormalities in circulating amino acids (AA) in hemodialysis patients. We evaluated the effects of a 12-month treatment with rH-EPO (150-250 U/kg/week) on blood AA levels in 10 patients with chronic renal failure under regular dialytic treatment. During treatment, hemoglobin levels increased from 7.0 +/- 0.3 to 10.1 +/- 0.3 g/dl at 3 months remaining steady thereafter. Before the treatment, patients showed reduced levels of essential AA (EAA), mainly valine, leucine and threonine (p < 0.05-0.01); among non-EAA (NEAA), aspartate and serine were reduced, whereas glycine, alanine, proline, citrulline and cyst(e)ine were increased (p < 0.05-0.001). Val/Gly, Ser/Gly and Tyr/Phe ratios were low (p < 0.05-0.01). Total EAA and total NEAA (619 +/- 21 and 1,382 +/- 75 mumol/l, respectively, before the study) were unchanged (639 +/- 22 and 1,410 +/- 89 mumol/l, respectively) at 12 months. Abnormalities in AA levels observed before the treatment persisted throughout the study. Only serine increased at the end of the study (p < 0.05). In conclusion, contrary to what has been reported, treatment with rH-EPO is not associated with an amelioration of AA metabolism in hemodialysis patients.

Adult↗

Muscle protein turnover and amino acid metabolism in patients with chronic renal failure.

Muscle protein turnover and amino acid (AA) exchange were studied in 4 patients with chronic renal failure (CRF) and in 5 controls in the postabsorptive state by using the forearm perfusion method together with the systemic infusion of 3H-Phe. In CRF patients muscle protein breakdown is increased and is associated with a parallel increase in protein synthesis. Protein breakdown is inversely related to arterial bicarbonate. Net proteolysis is unchanged. The release of total AA, glutamine and alanine is not different from controls, whereas the release of valine and leucine is reduced and serine uptake tends to be decreased. In conclusion, in postabsorptive patients with CRF, well before the uremic stage, an increased protein breakdown associated with metabolic acidosis takes place; net proteolysis is unaffected. Alterations in BCAA metabolism suggest the occurrence of increased BCAA degradation proceeding beyond the transamination step.

Adult↗

Reversed-phase high-performance liquid chromatographic analysis of branched-chain keto acid hydrazone derivatives: optimization of techniques and application to branched-chain keto acid balance studies across the forearm.

A sensitive method of quantifying branched-chain keto acids in plasma and whole blood samples is described. It is based on the separation by ion-pair reversed-phase liquid chromatography of 2,4-dinitrophenylhydrazine derivatives with ultraviolet detection. The sample clean-up steps that are usually required for reversed-phase high-performance liquid chromatography are eliminated. A reduction in ketoisocaproate isomer formation is obtained by incubation of derivatives in ice. The method is reproducible (coefficient of variation 2%, n = 5, at the 200-pmol level) and the ultraviolet response is linearly related to branched-chain keto acid concentration. Recoveries are high (greater than 95%). Other keto acids do not co-elute with branched-chain keto acids. Because of its sensitivity and precision, this method can be proposed for whole blood branched-chain keto acid balance studies across organs.

Biological Transport↗

[A community outbreak of Legionnaires' disease in Barcelona: epidemiologic and environmental study].

The investigation of the outbreak of legionellosis which developed in Barcelona in February 1988 included: 1) a case-control study, with the patients with Legionella pneumophila pneumonia (n = 56) and those with pneumonia by other organisms (n = 109) in the Hospital Clínic i Provincial (HCP); 2) a review of refrigeration towers and the water supply system; 3) a meteorological study, and 4) a survey of the construction works being carried out in the HCP area. The cases lived in the urban district 2 more often than the controls (odds ratio = 3.73, 95% confidence intervals 1.8-7.6), and were not associated with hospitals of hotels. L. pneumophila was not recovered from the environmental samples. The temperatures were unusually high, with a low air humidity. In the area near the HCP demolition materials were frequently removed. A causative focus was not detected; it cannot be ruled out, however, that the source of the outbreak was the removal of demolition materials in the affected area on the days preceding the epidemic outbreak.

Adult↗

[Polycenter evaluation of the break-point system].

Several research center have been set up to evaluate the system that deals with sensitivity to microbes under Sensititre break-point. The study has been broken down as follows: the break-point system was compared with the agar diffusion according to Bauer et al., using 1180 strains of fast-growing Gram-negative bacteria; a limited number of strains (176) have been used to compare the Sensititre break-point and the Sensititre MIC; results have been obtained testing 448 strains processed by break-point with correct inoculum and with simplified inoculum, from a colony; an investigation has been carried out on the time and cost of the break-point functioning. Having taken the Bauer system and others are compared them with the break-point, it was seen that their total agreement was 90.3% with 2% of major disagreement. The total major disagreement between Sensititre MIC and Sensititre break-point was 2.7%. The total major disagreement of the latter was largely the result of cephalotin (21%) on the Escherichia coli strains. An initial research centre has been formed to try to trow light upon the origins of such disagreements and we are now pleased to report back their initial findings. The preparation and reading of a test with the Bauer system and others takes about 18 minutes and costs 5600 Lit; a break-point test takes 10 minutes and costs 4500 Lit.

Agar↗

[Celiac disease and its diagnostic evolution. Comparisons and experiences in a hospital pediatric department (1975-1992). I].

The coeliac disease (CD) or gluten-sensitive enteropathy (GSE) is a permanent intolerance to wheat gliadin and to correlated proteins inducing malabsorption and typical damages of the jejunal mucosa (total or subtotal villous atrophy = SVA) in genetically-predisposed individuals ("DQW2"). A large amount of research has been devoted to CD pathogenesis: the most recent studies, thanks to sophisticated and experimental methods, support the pathogenetic immunological theory and the one of direct cytotoxicity. The correct diagnostic procedure for CD, established in 1970 by the European Society for Pediatric Gastroenterology and Nutrition (ESPGAN), suggested three small bowel mucosal biopsies. In the last years, because of the difficulties of such a practice, the necessity of non-invasive diagnostic approaches has developed; such approaches have been verified in absorption tests (one-hour blood xylose, intestinal permeability methods) and in immunogenetic tests (antibodies antigliadin, anti-reticulin, anti-endomysium, anti 90 KD glycoprotein, anti-human jejunum, HLA I/II antigens). The specific MHC antigens establish CD's incidence in several population and in particular situations, as in first-degree relatives and in diseases associated with CD (dermatitis herpetiformis (DH), insulin dependent diabetes mellitus (IDDM) and other auto-immune syndromes). The specific serum antibodies singly used as first level screening if estimated in combination with absorption tests, reach the highest levels of specificity and sensibility in CD diagnosis. It's anyway fundamental the comparison with at least a typical CD histological feature, caused by a challenge with a sufficient gluten to be carried in dubious cases and in non high auxological risk age (ESPGAN 1989). Adolescence is a period of frequent non compliance with a gluten-free diet and of particular psychological and physical problems: the apparent "gluten insensitivity", typical of teen-agers and adults, recalls the definitions of silent CD and latent CD (iceberg like). In the first case the jejunal mucosa is abnormal and the symptomatology isn't evident. In latent CD, genetically restricted, the mucosa is normal but there are minimal markers of inappropriate immunity to gliadin (at intestinal humoral immunity level) and a possible worsening of histological lesions to the third stage under environmental stimuli. This represents a two-stage model CD. That's why CD is still under-evaluated despite recent statistics reporting an increasing incidence (late and atypical forms). Prevalence rates between 1:300 and 1:4,000 and more are quoted in literature. The necessity of a strict gluten-free diet is confirmed by the evident frequency of lymphoma and by the increased risk of malignancy in untreated CD.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

[N.B.T. - PABA screening test for exocrine pancreatic function in healthy children. Preliminary investigation in 60 normal children].

The theoretical bases of PABA test as a diagnostic screening test of exocrine pancreatic insufficiency, its mode of execution and the findings obtained in 60 healthy subjects ranging in age from 2 to 14 years are reported. Those conditions related to extra-pancreatic disorders or to other factors that may interfere with the test and reduce its reliability are also discussed.

4-Aminobenzoic Acid↗