alpha-Cardiac actin (ACTC) binds to the band 3 (AE1) cardiac isoform

The band 3 protein is the major integral protein present in the erythrocyte membrane. Two tissue-specific isoforms area I so expressed in kidney alpha intercalated cells and in cardiomyocytes. It has been suggested that the cardiac isoform predominantly mediates the anion exchange in cardiomyocytes, but the role of the cytoplasmic domain of the band 3 (CDB3) protein in the cardiac tissue is unknown. In order to characterize novel associations of the CDB3 in the cardiac tissue, we performed the two-hybrid assay, using a bait comprising the region from leu 258 to leu 311 of the erythrocyte band 3, which must also be present in the cardiac isoform. The assay revealed two clones containing the C-terminal region of the a-cardiac actin. Immunoprecipitation of whole rat heart using an anti-actin antibody, immunoblotted with anti-human band 3, showed that actin binds to band 3 which was confirmed in the reverse assay. The confocal microscopy showed band 3 in the intercalated discs. Thus, besides the in vivo physical interaction in the Saccharomyces cerevisiae cell, we demonstrated using immunopreciptation that there is a physical association of band 3 with a-cardiac actin in cardiomyocyte, and we suggest that the binding occur 'in situ,' in the intercalated disc, a site of cell-cell contact and attachment of the sarcomere to the plasma membrane. (C) 2003 Wiley-Liss, Inc.8961215122

A novel mutation in the anion exchanger 1 gene is associated with familial distal renal tubular acidosis and nephrocalcinosis

Objective. The anion exchanger gene (AE1) or band 3 encodes a chloride- bicarbonate (Cl-/ HCO3-) exchanger expressed in the erythrocyte and in the renal alpha-intercalated cells involved in urine acidification. The purpose of the present study was to screen for mutations in the AE1 gene in 2 brothers ( 10 and 15 years of age) with familial distal renal tubular acidosis (dRTA), nephrocalcinosis, and failure to thrive. Methods. AE1 mutations were screened by single-strand conformation polymorphism, cloning, and sequencing. Results. A complete form of dRTA was confirmed in the 2 affected brothers and an incomplete form in their father. All 3 were heterozygous for a novel 20-bp deletion in exon 20 of the AE1 gene. This deletion resulted in 1 mutation in codon 888 (Ala-8883 --> Leu) followed by a premature termination codon at position 889, truncating the protein by 23 amino acids. As band 3 deficiency might lead to spherocytic hemolytic anemia or ovalocytosis, erythrocyte abnormalities were also investigated, but no morphologic changes in erythrocyte membrane were found and the osmotic fragility test was normal. Conclusions. A novel mutation in the AE1 gene was identified in association with autosomal dominant dRTA. We suggest that RTA be considered a diagnostic possibility in all children with failure to thrive and nephrocalcinosis.11261361136

Band 3 campinas: A novel splicing mutation in the band 3 gene (AE1) associated with hereditary spherocytosis, hyperactivity of Na+/Li+ countertransport and an abnormal renal bicarbonate handling

We have studied the molecular defect underlying band 3 deficiency in one family with hereditary spherocytosis using nonradioactive single strand conformation polimorphism of polymerase chain reaction (PCR) amplified genomic DNA of the AET gene, By direct sequencing, a single base substitution in the splicing donor site of intron 8 (position + 1G --> T) was identified, The study of the cDNA showed a skipping of exon 8, This exon skipping event is responsible for a frameshift leading to a premature stop codon 13 amino acids downstream. The distal urinary acidification test by furosemide was performed to verify the consequences of the band 3 deficiency in cu intercalated cortical collecting duct cells (alpha ICCDC), We found an increased basal urinary bicarbonate excretion, associated with an increased basal urinary pH and an efficient distal urinary acidification, We also tested the consequences of band 3 deficiency on the Na+/H+ exchanger, by the measurement of Na+/Li+ countertransport activity in red blood cells. The Na+/Li+ countertransport activity was increased threefold to sixfold in the patients compared with the controls. It is possible that band 3 deficiency in the kidney leads to a decrease in the reabsorption of HCO3- in alpha ICCDC and anion loss, which might be associated with an increased sodium-lithium countertransport activity. (C) 1997 by The American Society of Hematology.9072810281

Renal haemodynamic responses to a chicken or beef meal in normal individuals

Background. In normal subjects, protein loading with soybean meal does not produce the same renal haemodynamic effects as those observed with a beef meal. The renal responses of an acute protein load in the form of chicken meal is unknown. Methods. To examine whether the renal response to a chicken meal differs from that to beef, we studied the renal function of eight normal healthy volunteers before and after a protein load with each of these meals. In a crossover randomized study, we measured the glomerular filtration rate (GFR; inulin clearance), renal plasma flow (RPF; para-aminohippurate clearance) and, plasma amino acid and glucagon levels. We also determined the amino acid content of a sample of chicken and beef. Results. GFR and RPF increased significantly 2 h after both the chicken and beef meals (chicken, 98 +/- 13 vs 119 +/- 18 and 476 +/- 123 vs 570 +/- 99ml/min/1.73 m(2); beef, 107 +/- 14 vs 122 +/- 16 and 501 +/- 118 vs 560 +/- 97 ml/min/1.73 m(2), for GFR and RPF at basal and 2 h respectively, P < 0.05). Renal vascular resistance decreased and the filtration fraction remained unchanged after both protein loads. The changes induced by the protein challenges in the plasma amino acid and glucagon levels were not different between the two protein sources. The amino acid contents of chicken and beef samples were similar. Conclusion. In normal subjects, chicken and beef meals induced a similar degree of hyperfiltration.1392261226

Core-shell CdS/Cd(OH)(2) quantum dots: synthesis and bioconjugation to target red cells antigens

We report a new and efficient methodology of labelling red blood cells, in order to investigate the expression of anti-A antigen, employing luminescent semiconductor nanocrystals. Highly luminescent and stable core-shell cadmium sulphide/cadmium hydroxide [CdS/CdS(OH)(2)] colloidal particles were obtained in the nanometre size range. The surface of these particles was characterized by using a monoclonal anti-A antibody via a one-step glutaraldehyde cross-linking procedure, followed by conjugation of the particles to red cells of blood groups A(+), A(2)(+) and O+. Laser scanning confocal microscopy images indicated that after conjugation for 30 min, A(+) and A(2)(+) erythrocytes presented different patterns of dual bright emission whereas the O+ group cells showed no emission. We suggest that this labelling procedure may be applied as a quantitative tool to investigate the distribution and expression of alloantigen in red blood cells.219310310

Investigation of red blood cell antigens with highly fluorescent and stable semiconductor quantum dots

We report a new methodology for red blood cell antigen expression determination by a simple labeling procedure employing luminescent semiconductor quantum dots. Highly luminescent and stable core shell cadmium sulfide/cadmium hydroxide colloidal particles are obtained, with a predominant size of 9 nm. The core-shell quantum dots are functionalized with glutaraldehyde and conjugated to a monoclonal anti-A antibody to target antigen-A in red blood cell membranes. Erythrocyte samples of blood groups A(+), A(2)(+), and O+ are used for this purpose. Confocal microscopy images show that after 30 min of conjugation time, type A(+) and A(2)(+) erythrocytes present bright emission, whereas the O+ group cells show no emission. Fluorescence intensity maps show different antigen expressions for the distinct erythrocyte types. The results obtained strongly suggest that this simple labeling procedure may be employed as an efficient tool to investigate quantitatively the distribution and expression of antigens in red blood cell membranes. (C) 2005 Society of Photo-Optical Instrumentation Engineers.10

Direitos das pessoas com transtorno mental autoras de delitos The rights of criminally insane individuals

O Movimento pela Reforma Psiquiátrica tem subsidiado propostas de reorientação do modelo assistencial hegemônico em saúde mental. Para a assistência às pessoas com transtorno mental autoras de delitos instituiu-se o manicômio judiciário, atualmente denominado Hospital de Custódia e Tratamento Psiquiátrico (HCTP). A manutenção dessa estrutura, reconhecida como instituição total, tem reforçado a exclusão individual, limitando a reinserção social dos internos. Este artigo discute o direito à saúde nos HCTP na perspectiva dos direitos humanos. Os avanços conferidos pela Política Nacional de Saúde Mental não têm contemplado a reorientação da prática assistencial desenvolvida no âmbito do HCTP. Essa instituição tem preservado o seu caráter asilar/segregacionista, evidenciando uma tradição fundada na negação dos direitos humanos. O avanço normativo não consolida, de per si, a materialização das recentes conquistas advindas a partir da Reforma Psiquiátrica, particularmente quanto ao segmento das pessoas com transtorno mental autoras de delitos. O Estado, em co-responsabilidade com a sociedade, deve promover a efetiva reorientação do modelo de atenção à saúde dessas pessoas, cuja responsabilidade penal deverá ser reconhecida ao tempo em que se propicie o tratamento especializado. O respeito aos direitos humanos não implica a inimputabilidade.<br>The Psychiatric Reform Movement has supported proposals to reorient the hegemonic mental health care model. In Brazil, a facility for the criminally insane was created, called the Custody and Psychiatric Treatment Hospital (CPTH). The maintenance of such a structure, known as total institutionalization, has reinforced individual exclusion, limiting the patients' social rehabilitation. This article discusses the right to health in the CPTH from a human rights perspective. The advances achieved in Brazil under the National Mental Health Policy have failed to include reorientation of the care provided in such facilities for the criminally insane. The institution has remained an isolationist asylum, reflecting a historical denial of human rights. Progress in policy, per se, does not guarantee the materialization of recent strides gained through the Psychiatric Reform, particularly in relation to criminals with mental disorders. The state, through shared responsibility with society, should promote the effective reorientation of the health care model for these individuals, whose criminal responsibility should be acknowledged, while providing simultaneously for specialized care. Respect for human rights is not synonymous with impunity