Pseudostenosis of axillary vein due to adduction of the upper limb.

Axillary vein stenosis is a well-documented complication in hemodialysis (HD) patients, but in adipose or athletic subjects, pseudostenosis of the axillary vein can be detected. We report a case of pseudostenosis in a fit dialysis patient who underwent phlebography of the right upper limb, performed to create a new vascular access (VA). The investigation demonstrated that the axillary vein appeared sharpened with a reduced lumen. Based on this exam, angioplasty of the right axillary vein was planned. The new phlebographic study, performed abducting the arm, demonstrated that the previously marked stenosis of the axillary vein disappeared. Our case illustrates how the reduction of the axillary vein lumen was secondary to ""muscular print"" and was present only if the arm was adducted. In uremic patients, the squeezing of the vascular nervous bundle of the upper limb is possible in fit patients at the time of phlebography, an examination that should be performed with the arm both in adduction and abduction.

HBV-related cutaneous periarteritis nodosa in a patient 16 years after renal transplantation: efficacy of lamivudine.

Cutaneous periarteritis nodosa (PAN) is a clinical feature characterized by chronic, benign course; its pathogenesis is unknown. In patients submitted to renal transplantation cutaneous PAN is a rare complication. We report a case of cutaneous PAN associated with the reappearance of hepatitis B antigen 16 years after kidney transplantation. A 44-year-old man underwent successful renal transplantation in June 1980. In December 1996 he presented multiple painful erythematous subcutaneous nodules on both legs. Skin lesion biopsy showed the presence of cutaneous PAN. Six months later laboratory data demonstrated the presence of HbsAg. HBeAg, HBcAb and detectable HBV-DNA serum by polymerase-chain-reaction (PCR) assay. Anti-HBs and anti-HBe proved negative. In July 1998 the laboratory tests showed an important increase of HBV-DNA (5.1 billion by Branched DNA), and so lamivudine (100 mg/day) was introduced. HBV-DNA became undetectable by PCR after 3 months of therapy. Seven months later a new skin biopsy was performed. The typical signs of PAN were no longer evident. As HBV infecion was demonstrated six months after the clinical appearance of the PAN, in a patient who was believed to be immune to the virus, it is possible that, in the early stages, the hepatitis B antigen title was methodologically indeterminable, but sufficient to form circulating immune complexes responsible for vasculitis primer. Lamivudine therapy resulted efficacious in favouring the regression of cutaneous PAN, but its long-term efficacy requires further evaluation as regards potential selection of drug resistant hepatitis B virus (HBV) mutants during treatment.

Erythropoietin and cardiocirculatory condition in aged patients with chronic renal failure.

BACKGROUND/AIM: The clearest benefit of recombinant human erythropoietin (rHuEPO) in end-stage renal disease is a substantial reduction in transfusion dependency and an improved quality of life. In this report, we describe the efficacy of weekly subcutaneous administration of rHuEPO in 11 elderly patients with anemia secondary to chronic renal failure. METHODS: The role of rHuEPO therapy in increasing the patient's quality of life and in decreasing the hospitalization rates secondary to cardiac morbidity was verified in 11 elderly patients (age range between 66 and 85 years) with anemia due to chronic renal failure. The mean hemoglobin level at the beginning of the study was 8.2 +/- (SD) 0.7 g/dl, and the serum creatinine concentration was 4.8 +/- 1.36 mg/dl. The patients underwent baseline and annual echocardiography, in addition to an electrocardiogram. RESULTS: Most patients experienced a partial regression of left ventricular hypertrophy, and no congestive heart failure was documented. The mean hemoglobin level during rHuEPO therapy increased to 11.3 +/- 1.2 g/dl, while the mean serum creatinine concentration did not change significantly. CONCLUSIONS: Our results confirm that early anemia correction in aged chronic renal failure patients permits improvement of the quality of life, of exercise performance, and of cognitive functions. Reduced transfusion need and regression of left ventricular hypertrophy favor a minor incidence of cardiac morbidity and contribute to reduce health costs.

Self-categorization, affective commitment and group self-esteem as distinct aspects of social identity in the organization.

The purpose of this study is to distinguish between cognitive, affective and evaluative components of social identity in the organization and to show how the components instigate behaviours that benefit in-group members. A new scale for measuring cognitive organizational identification (i.e. self-categorization) is developed and compared to a leading scale. Internal consistency, convergent validity, predictive validity and generalizability of the two scales are established on a sample of Italian (N = 409) and Korean (N = 283) workers. Next, convergent and discriminant validity for measures of organizational identification, affective commitment and group self-esteem are demonstrated. Then, two antecedents of these components of social identity are examined: organization prestige and organization stereotypes. Finally, the mediating role of the components of social identity are investigated between the antecedents and five forms of citizenship behaviours. The last three analyses are performed on the Italian (N = 409) workers. Among other findings, the results show that affective commitment and self-esteem are the primary motivators of citizenship behaviours. Moreover, cognitive identification performs as a central mediator between prestige and stereotypes on the one hand, and affective commitment and self-esteem on the other. Identification is thus an indirect determinant of citizenship behaviours.

High-sensitivity electrophoretic method for the detection of Bence Jones protein and for the study of proteinuria in unconcentrated urines.

The study of proteinuria, and especially the search for Bence Jones proteins (BJP), has almost always required urine concentration. We evaluated a high-sensitivity electrophoretic method using unconcentrated urine based on colloidal gold staining. The sensitivity for the detection of BJP is further enhanced by immunofixation. Sensitivity to BJP is better than 1 mg/L and, apart from the alpha-1 microglobulin, all the proteins relevant to the classification of proteinuria can be visualized with a sensitivity of approximatively 3 mg/L.

Reference values for immunoglobulin kappa and lambda light chains and the kappa/lambda ratio in children's serum.

We analyzed 708 serum samples from healthy children and adolescents by immunonephelometry to obtain reference values for the immunoglobulin kappa (kappa) and lambda (lambda) light chains and for their ratio at a time of life when immunoglobulin synthesis is maturing and continually being stimulated. The lambda chain concentration that is to be maintained throughout the child's life is reached very early, just after 1 year, whereas the concentration of the kappa chains, which increases gradually, reflects the concentration of the immunoglobulins as a whole. These reference values may be useful for studying kappa and lambda chains in illnesses involving the immune system in children.

Occurrence of monoclonal components in general practice: clinical implications.

We report on the occurrence of monoclonal components observed in a provincial hospital in northern Italy from 1987 to 1990. The monoclonal components were detected by visual inspection of high-resolution acetate serum electrophoreses and typed by immunofixation. The percentage of monoclonal components increases steeply with age, and reaches a plateau of 7-8% in individuals over 55 years old. Besides the high percentage of monoclonal component, the other relevant finding of this study is that approximately 80% of monoclonal components are of low concentration (less than 5 g/l). Most of these subjects with small monoclonal component passed undetected in the previous studies on the prognostic significance of monoclonal gammapathy. These findings indicate the need for a revision of the current concepts on the biological and clinical significance of MC discovered by chance.

Use of immunoglobulin heavy-chain and light-chain measurements in a multicenter trial to investigate monoclonal components: I. Detection.

We assessed the combined use of serum protein electrophoresis (SPE) and nephelometric measurement of immunoglobulin heavy- and light-chain components for detecting serum monoclonal immunoglobulins (monoclonal components, MC) in 4788 unselected samples from 4173 patients. MC were detected in 514 samples from 390 patients. In 356 these were detected by SPE; the other 34 had a normal SPE pattern but an abnormal kappa:lambda light-chain ratio (KLR). Only 208 of the 356 (58%) samples with bands by SPE had abnormal KLRs. Samples with MC concentrations greater than 5 g/L had a higher proportion of abnormal KLRs (75%) than those with concentrations less than 5 g/L (42%). The KLR was abnormal in 13% of samples in which no MC were visible by SPE or immunofixation electrophoresis (IFE). Compared with quantitative measurements of immunoglobulin heavy and light chains, high-quality SPE remains the method of choice for the detection of MC. Quantitative methods, however, are able to detect additional MC, especially those containing free light chains, and in the absence of SPE and IFE will detect about 75% of MC present at greater than 5 g/L.

Use of immunoglobulin heavy-chain and light-chain measurements in a multicenter trial to investigate monoclonal components: II. Classification by use of computer-based algorithms.

We describe a computer algorithm for classifying serum monoclonal proteins (MC) based on serum protein electrophoresis (SPE) and the automated measurement of kappa and lambda light chains and IgG, IgA, and IgM. We developed the algorithm by using a large database of unselected samples containing MC collected in a multicenter study. The performance of the algorithm was optimized by using iterative computational procedures and was tested on both the development database and on an independent set of MC-containing samples. With the development database, the algorithm correctly classified 50% and misassigned 2.5% of the MC. Where the MC were present in concentrations greater than 10 g/L, the rate of successful classification increased to 72% with 3% misclassification. When the algorithm was tested on a group of 101 MC-containing samples from an independent source, 67% were correctly classified and 8% misclassified, half of the latter being unusual IgD myelomas. We discuss the scope for the application of the algorithm in routine laboratory practice involving personal computer software.

Restricted electrophoretic heterogeneity of immunoglobulin light chains in urine: a cause for confusion with Bence Jones protein.

The detection of Bence Jones protein, an important part of the investigation of suspected myeloma, is most commonly done by agarose or cellulose nitrate electrophoresis followed by immunofixation. Bence Jones protein is recognized as single or multiple bands of one type of light chain. Unfortunately, improvements in sensitivity of these techniques (use of high-affinity antisera and higher resolution electrophoresis) frequently allow detection of multiple light chain bands in the urine of patients who do not have a B-cell dyscrasia. The bands are usually kappa, although they may be accompanied by lambda bands. This pattern may lead to the misdiagnosis of Bence Jones protein and oligoclonal light chain production in patients. Here we show that this pattern is produced by polyclonal light chains; it is present in the urine of all patients with a tubular proteinuria of any etiology and may be induced in healthy individuals by blocking their renal tubular protein reabsorption. Polyclonal light chains separate into monomers and dimers on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and into four major bands with many minor bands by isoelectric focusing. This difference in charge and possibly size results in the banding pattern seen on good-quality electrophoresis and immunofixation.

Purification and Characterization of a Polygalacturonase-Inhibiting Protein from Phaseolus vulgaris L.

Homogeneous endo-polygalacturonase (PG) was covalently bound to cyanogen-bromide-activated Sepharose, and the resulting PG-Sepharose conjugate was utilized to purify, by affinity chromatography, a protein from Phaseolus vulgaris hypocotyls that binds to and inhibits PG. Isoelectric focusing of the purified PG-inhibiting protein (PGIP) showed a major protein band that coincided with PG-inhibiting activity. PGIP formed a complex with PG at pH 5.0 and at low salt concentrations. The complex dissociated in 0.5 m Na-acetate and pH values lower than 4.5 or higher than 6.0. Formation of the PG-PGIP complex resulted in complete inhibition of PG activity. PG activity was restored upon dissociation of the complex. The protein exhibited inhibitory activity toward PGs from Colletotrichum lindemuthianum, Fusarium moniliforme and Aspergillus niger. The possible role of PGIP in regulating the activity of fungal PG's and their ability to elicit plant defense reactions are discussed.

[Behavior and significance of phalangeal bone changes in uremic patients under periodic hemodialysis treatment]. / Comportamento e significato delle alterazioni scheletriche falangee nell'uremico in trattamento emodialitico periodico.

Bone damage in hand phalanges has been evaluated with reference to age and duration of hemodialysis (on the basis of 248 radiological observations), in 93 cases with chronic renal failure (age: 20-59 years). These patients were on regular dialytic treatment (RDT) from 1 to 138 months. 72% of the patients underwent several periodic (annual) controls using the mammographic technique. The radiologic evaluations have been arranged into groups according to age. Skeletal damage was more evident when RDT was prolonged. Bone damage increases with age in the first 48 months; afterwards, on the contrary, bone changes were more evident in middle aged patients. At the beginning of RDT, acroosteolysis was the most important change always present. Both subperiosteal and intracortical resorption are more evident increasing age and duration of RDT. Radiological changes give a clear picture of the possible histo-morphologic pattern that characterizes uremic osteodystrophy.

The influence of chloride and other univalent inorganic anions on the visible-absorption spectrum of aspartate aminotransferase.

1. The influence of Cl(-), Br(-), NO(3) (-) and F(-) ions on the visible-absorption spectrum of deionized aspartate aminotransferase was investigated. 2. Except for F(-), these anions caused an increase of the extinction at 430mmu with a concomitant decrease of that at 362mmu. 3. The affinity constants for Cl(-) and NO(3) (-) ions were calculated by a procedure based on the assumption that the anion stabilizes the protonated form of the enzyme chromophore (lambda(max.) 430mmu). 4. The true pK of the chromophore of the enzyme was found to be 5.25.