Dietary magnesium supplementation ameliorates anemia in a mouse model of beta-thalassemia.

To ascertain the quantitative effect on the disease beta-thalassemia of a low-magnesium (Mg) diet compared with a high-Mg diet and a standard-Mg diet, we studied the effect these diets had over a 4-week period on beta-thalassemic (beta thal) mice compared with normal C57BL/6 mice used as controls. The low-Mg diet consisted of 6 +/- 2 mg Mg/kg body weight/d, the high-Mg diet 1,000 +/- 20 mg Mg/kg body weight/d, and the standard-Mg diet 400 +/- 20 mg Mg/kg body weight/d. Beta thal mice that were fed the low-Mg diet became more anemic, had reduced serum and erythrocyte Mg, and had decreased erythrocyte K.

Autoimmune enteropathy and villous atrophy in adults.

Background: Autoimmune enteropathy is a condition described in children and characterised by villous atrophy, which is unresponsive to any dietary restrictions, and by the presence of enterocyte autoantibodies. We report two adult patients who fulfilled all the criteria for the diagnosis of this disorder.

Methods: Over the past 5 years we have seen four adult patients (all women, median age 51.

Membrane cation and anion transport activities in erythrocytes of hereditary spherocytosis: effects of different membrane protein defects.

Hereditary spherocytosis (HS) is due to different membrane protein defects (i.e., deficiency of spectrin and ankyrin, band 3, or band 4.

Study of cell kinetics in the normal colorectal mucosa of subjects at risk of developing colorectal carcinoma.

This report examines the 3H-thymidine-labeling index (LI), the flow cytometric S-phase cell fraction, and DNA ploidy in the normal colorectal mucosa of three groups of subjects: normal subjects (group A), patients with adenomas (group B) and patients with cancer (group C). The total LI and the LI for crypt compartment were investigated. The former LI was similar in the three groups while that for crypt compartment was significantly higher in the patients with adenomas (compartment 3), and in those with cancer (compartments 3 and 4).

Organ-specific autoantibodies in coeliac disease: do they represent an epiphenomenon or the expression of associated autoimmune disorders?

Background And Aims: The occurrence of autoimmune disorders and organ-specific autoantibodies has been reported in coeliac disease. We assessed the prevalence of organ-specific autoantibodies in coeliac patients and evaluated whether their finding is an expression of associated autoimmune diseases.

Methods: Sera from 70 coeliac disease patients were tested for thyroid microsomal, gastric parietal cell, adrenal cortex and pancreatic islet cell antibodies by indirect immunofluorescence on O blood group human tissues.

Deficiency of Src family kinases Fgr and Hck results in activation of erythrocyte K/Cl cotransport.

Src-family kinases play a central role in regulation of hematopoietic cell functions. We found that mouse erythrocytes express the Src-family kinases Fgr and Hck, as well as Lyn. To directly test whether Fgr and Hck play any role in erythrocyte function, we analyzed red cells isolated from fgr-/-, hck-/-, and fgr-/- hck-/- knock-out mice.

Modulation of erythrocyte potassium chloride cotransport, potassium content, and density by dietary magnesium intake in transgenic SAD mouse.

Prevention of erythrocyte dehydration is a potential therapeutic strategy for sickle cell disease. Increasing erythrocyte magnesium (Mg) could inhibit sickle cell dehydration by increasing chloride (CI) and water content and by inhibiting potassium chloride (K-CI) cotransport. In transgenic SAD 1 and (control) C57BL/6 normal mice, we investigated the effect of 2 weeks of diet with either low Mg (6 +/- 2 mg/kg body weight/d) or high Mg (1,000 +/- 20 mg/kg body weight/ d), in comparison with a diet of standard Mg (400 +/- 20 mg/ kg body weight/d).

Differences in platelet count and size between marrow and peripheral blood.

Automatized platelet parameters were evaluated in 23 unselected patients undergoing a bone marrow examination for diagnostic purposes, both in medullary and in peripheral blood, with the aim of investigating the biological significance of platelet volume heterogeneity. In the marrow blood the platelet count was 10.07 +/- 21.

Human umbilical cord as substrate for IgA antiendomysial antibodies allows large scale screening for celiac sprue.

Sera from 800 patients referred to our laboratory for celiac sprue screening were tested for IgA antiendomysial antibodies on human umbilical cord (HUC-EmA) and for IgA and IgG antigliadin antibodies (AGA) on rodent tissue by indirect immunofluorescence. Thirty-three patients (4.1%) were positive for at least one of the two antibodies; IgA HUC-EmA were found in 25 patients, whereas IgA and IgG AGA were detected in 19 and 24 subjects, respectively.

Combination therapy of erythropoietin, hydroxyurea, and clotrimazole in a beta thalassemic mouse: a model for human therapy.

beta thalassemia (beta thal) in DBA/2J mice is a consequence of the spontaneous and complete deletion of the beta major globin gene. Homozygous beta thal mice have clinical and biological features similar to those observed in human beta thal intermedia. Erythrocytes in human beta thal are characterized by a relative cell dehydration and reduced K+ content.

Omega-3 polyunsaturated fatty acid supplements and ambulatory blood pressure monitoring parameters in patients with mild essential hypertension.

Objective: To evaluate the effects of low doses of omega-3 polyunsaturated fatty acids on ambulatory blood pressure monitoring parameters in a group of mild essential hypertensives.

Patients: We studied 24 consecutive essential hypertensive patients from our outpatient clinic with mild hypertension (diastolic blood pressure < or = 105 mmHg), no previous treatment for 4 weeks at least and no other disease.

Methods: After a 3-month run-in period, the patients entered an intervention phase and were given 3 g omega-3 polyunsaturated fatty acids (85% eicosapentaenoic and docosahexaenoic acid concentrate) daily for 4 months; this phase was followed by a 4-month washout period.

Molecular basis for the recently described hereditary hyperferritinemia-cataract syndrome: a mutation in the iron-responsive element of ferritin L-subunit gene (the "Verona mutation").

Recently, we described a new genetic disorder (the "hereditary hyperferritinemia-cataract syndrome") clinically characterized by the combination of elevated serum ferritin and congenital bilateral nuclear cataract, both cotransmitted as an autosomal dominant trait. In affected subjects, hyperferritinemia (ranging from 950 to 2,259 micrograms/L) is typically not related to iron overload. Differently from subjects with hereditary hemochromatosis, they have normal to low levels of serum iron and percent of transferrin saturation and absence of iron overload in parenchymal organs.

Red blood cell cation transports in uraemic anaemia: evidence for an increased K/Cl co-transport activity. Effects of dialysis and erythropoietin treatment.

This study examines the role of uraemia and the effect of different dialysis treatments on red cell cation transport. We evaluated the main cation transport systems in erythrocytes of non-dialysed end-stage renal disease (ESRD) subjects, of patients undergoing haemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD), as well as the changes induced by human recombinant erythropoietin (r-HuEPO) administration. In uraemic undialysed and dialysed patients, we observed an increase in K/Cl co-transport activity and in shrinkage-induced amiloride-sensitive (HMA-sensitive) Na efflux (Na/H exchange) and a decrease in Na/K pump and Na/K/Cl co-transport activity, while Na/Li exchange was increased only in dialysed patients.

Sulfhydryl oxidation and activation of red cell K(+)-Cl- cotransport in the transgenic SAD mouse.

The SAD mouse is characterized by the expression of human SAD hemoglobin (Hb), a super S Hb with a higher tendency to polymerize than HbS due to the presence of two additional mutations, Antilles beta 23Ile and D Punjab beta 121Glu. Monovalent cation transport was studied in erythrocytes from SAD-1 (Hb SAD = 19%) and beta-thal/SAD-1 (Hb SAD = 26%) mice. Erythrocytes containing Hb SAD exhibited dehydration, increased maximal rate of Na(+)-K+ pump, unchanged Rb+ flux via the Gardos channel, and increased K(+)-Cl- cotransport.

Ca(2+)-activated K+ channels of human and rabbit erythrocytes display distinctive patterns of inhibition by venom peptide toxins.

Despite recent progress in the molecular characterization of high-conductance Ca(2+)-activated K+ (maxi-K) channels, the molecular identities of intermediate conductance Ca(2+)-activated K+ channels, including that of mature erythrocytes, remains unknown. We have used various peptide toxins to characterize the intermediate conductance Ca(2+)-activated K+ channels (Gardos pathway) of human and rabbit red cells. With studies on K+ transport and on binding of 125I-charybdotoxin (ChTX) and 125I-kaliotoxin (KTX) binding in red cells, we provide evidence for the distinct nature of the red cell Gardos channel among described Ca(2+)-activated K+ channels based on (i) the characteristic inhibition and binding patterns produced by ChTX analogues, iberiotoxin (IbTX) and IbTX-like ChTX mutants, and KTX (1-37 and 1-38 variants); (ii) the presence of some properties heretofore attributed only to voltage-gated channels, including inhibition of K transport by margatoxin (MgTX) and by stichodactyla toxin (StK); (iii) and the ability of scyllatoxin (ScyTX) and apamin to displace bound 125I-charybdotoxin, a novel property for K+ channels.

IgA anti-endomysial antibodies on human umbilical cord tissue for celiac disease screening. Save both money and monkeys.

Since celiac disease screening by traditional IgA anti-endomysial antibody test is limited by high costs of monkey esophagus commercial kits as well as by rising ethical problems related to the endangered species, the identification of an inexpensive and commonly available substrate for this antibody determination is urgently required. To achieve this goal, we compared the prevalence of IgA anti-endomysial antibodies detected on monkey esophagus with that on human umbilical cord. Fifty-seven (95%) of 60 untreated adult celiacs were positive for these antibodies on monkey esophagus as well as on human umbilical cord.

A linkage between hereditary hyperferritinaemia not related to iron overload and autosomal dominant congenital cataract.

The only genetic disorder with elevated serum ferritin levels so far described is hereditary HLA-related haemochromatosis. On the other hand, hereditary cataract is both genotypically as well as phenotypically heterogenous, and no specific locus or any useful marker has been yet identified. We studied two Italian families in whom a combination of elevated serum ferritin not related to iron overload and congenital nuclear cataract is transmitted as an autosomal dominant trait.

IFL- and ELISA-antigliadin antibodies recognize different antigenic reactivities from those of R1-antireticulin and antiendomysial antibodies.

In order to establish whether antigliadin antibodies, detected by indirect immunofluorescence (IFL-AGA), display the same antibody reactivity as ELISA-AGA or whether they cross-react with reticulin antibodies (R1-ARA and antiendomysial--EmA), sera from 16 untreated coeliac patients were repeatedly absorbed with crude gliadin dissolved in ethanol/water solution. The comparison between antibody activities before and after absorption demonstrated that IFL-AGA and ELISA-AGA are nothing but a single antibody, as both of them completely disappeared or markedly reduced their titre after incubation with crude gliadin. Moreover, AGA reactivity differs from the reactivity of antibodies directed against reticulin, as R1-ARA and EmA titres were not affected by crude gliadin absorption.

Specific reactivity of fluorescein isothiocyanate-conjugated separated IgG and IgA from celiac disease sera on human tissues.

Study of the reaction of celiac disease-related antibodies with human substrates has been hampered by the immunological cross-reactivity between fluorescein isothiocyanate-conjugated anti-human immunoglobulins and immunoglobulins normally present in human tissues. In order to overcome this problem we extracted IgG from 2 celiac disease sera (positive for specific IgG and IgA antibodies) using a genetically engineered recombinant form of streptococcal protein G covalently immobilized on 4% agarose beads. The separated IgG and IgA was conjugated with fluorescein isothiocyanate and used in direct immunofluorescence on 0 blood group human duodenum, liver, and myocardium.

Oxidative damage and erythrocyte membrane transport abnormalities in thalassemias.

Oxidative damage induced by free globin chains has been implicated in the pathogenesis of the membrane abnormalities observed in alpha and beta thalassemia. We have evaluated transport of Na+ and K+ in erythrocytes of patients with thalassemias as well as in two experimental models that use normal human red blood cells, one for alpha thalassemia (methylhydrazine treatment, alpha thalassemia like) and one for beta thalassemia (phenylhydrazine treatment, beta thalassemia like). With the exception of the Na-K pump, similar alterations in membrane transport were observed in thalassemia and thalassemia-like erythrocytes.

Carotid artery endarterectomy in patients with contralateral carotid artery occlusion: perioperative hazards and late results.

The aim of this study was to analyze and compare the perioperative hazards and late results of internal carotid endarterectomy (CEA) in patients with and without contralateral internal carotid artery occlusion. From March 1980 to April 1990, 375 consecutive patients underwent 439 CEAs at the First Department of Vascular Surgery of Padova Medical School. Patients were divided into two groups; group 1 (61 patients) had contralateral internal carotid artery occlusion and group 2 (314 patients) did not (378 CEAs, 64 bilateral).

Treatment with oral clotrimazole blocks Ca(2+)-activated K+ transport and reverses erythrocyte dehydration in transgenic SAD mice. A model for therapy of sickle cell disease.

Prevention of red cell K+ and water loss is a therapeutic strategy for sickle cell disease. We have investigated in vitro and in vivo the effects of clotrimazole (CLT) and miconazole (MIC) on transgenic mice red cells expressing hemoglobin SAD. CLT blocked the Gardos channel (ID50 75 +/- 22 nM; n = 3) and the A23187-induced dehydration of Hbbs/Hbbthal SAD 1 mouse erythrocytes in vitro.

Flow cytometric study of lymphocyte subsets in patients at different stages of colorectal carcinoma.

Purpose: The evaluation of lymphocyte subsets by using monoclonal antibodies in neoplastic patients has provided different results, partly in relation to the stage of the disease. Therefore, as a preliminary study of cancer patients treated with immunomodulating drugs, an analysis of lymphocyte subsets was performed in colorectal carcinoma patients.

Methods: In this study, a flow cytometric evaluation of lymphocyte subsets was performed in 33 patients affected by colorectal carcinoma, with or without metastases.