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1.
Sci Rep ; 12(1): 6934, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484384

RESUMO

The immune system has been described to play a role in the development of Alzheimer's disease (AD), but the distribution of immunoglobulins and their subclasses in brain tissue has not been explored. In this study, examination of pathologically diagnosed frontal cortex gray matter revealed significantly higher levels of IgM and IgG in late-stage AD (Braak and Braak stages V and VI) compared to age-matched controls. While levels of IgG2 and IgG4 constant region fragments were higher in late-stage AD, concentration of native-state IgG4 with free Fc regions was increased in AD III and VI. RNA analysis did not support parenchymal B-cell production of IgG4 in AD III and V, indicating possible peripheral or meningeal B-cell involvement. Changes in the profile of IgM, IgG and IgG subclasses in AD frontal cortex may provide insight into understanding disease pathogenesis and progression.


Assuntos
Doença de Alzheimer , Encéfalo , Lobo Frontal , Humanos , Imunoglobulina G , Imunoglobulina M
2.
Alzheimers Dement (N Y) ; 6(1): e12040, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32607408

RESUMO

INTRODUCTION: Mutations in brain tissues that cumulate with age may contribute to Alzheimer's disease (AD). Abnormal glycoprotein and Tn antigen expression have been demonstrated in AD. We identified C1GALT1C1/COSMC mutations in AD and age-matched normals without AD. The COSMC coding mutations resulted in a significant reduction in T-synthase activity in advanced AD cases. METHODS: Identification of COSMC mutations, Real-Time Quantitative Reverse Transcription PCR (Q-RT-PCR), western blotting, and T-synthase activity assays. RESULTS: COSMC mutations were detected in the promotor, coding region and 3'UTR in AD and normals. COSMC coding mutations demonstrated a correlation with AD progression. T-synthase levels were significantly elevated in advanced AD compared to AD III (P = 0.03) and normals (P = 0.002). T-synthase activity in advanced AD {Braak and Braak (B&B) stages V and VI} with COSMC coding mutations was 3-fold lower than advanced AD without mutations, and 1.3-fold lower than normal (P = 0.001) and AD B&B stage III (P = 0.01) with coding mutations. DISCUSSION: COSMC coding mutations significantly diminished T-synthase activity in advanced AD, potentially causing defective galactosylation.

4.
PLoS One ; 8(4): e61752, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23593496

RESUMO

The growing body of clinical and experimental data regarding electromagnetic field (EMF) bioeffects and their therapeutic applications has contributed to a better understanding of the underlying mechanisms of action. This study reports that two EMF modalities currently in clinical use, a pulse-modulated radiofrequency (PRF) signal, and a static magnetic field (SMF), applied independently, increased the rate of deoxygenation of human hemoglobin (Hb) in a cell-free assay. Deoxygenation of Hb was initiated using the reducing agent dithiothreitol (DTT) in an assay that allowed the time for deoxygenation to be controlled (from several min to several hours) by adjusting the relative concentrations of DTT and Hb. The time course of Hb deoxygenation was observed using visible light spectroscopy. Exposure for 10-30 min to either PRF or SMF increased the rate of deoxygenation occurring several min to several hours after the end of EMF exposure. The sensitivity and biochemical simplicity of the assay developed here suggest a new research tool that may help to further the understanding of basic biophysical EMF transduction mechanisms. If the results of this study were to be shown to occur at the cellular and tissue level, EMF-enhanced oxygen availability would be one of the mechanisms by which clinically relevant EMF-mediated enhancement of growth and repair processes could occur.


Assuntos
Hemoglobinas/metabolismo , Campos Magnéticos , Ondas de Rádio , Eletricidade Estática , Sistema Livre de Células , Humanos , Luz , Análise Espectral , Ureia/farmacologia
5.
Anal Biochem ; 416(1): 92-9, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21605540

RESUMO

A new method for extraction and concentration of organic dyes that uses a reagent composed of a nonionic detergent mixed with an alcohol is described. We have observed that water-soluble organic dyes are also soluble in nonionic detergents and can be extracted by adding salt, which separates the dye-detergent component from the aqueous phase. We have also found that mixing nonionic detergents with alcohols markedly reduces their viscosity and produces stable, free-flowing, and effective reagents for color extraction. On the basis of these observations, we used a mixture of Triton X-100 and 1-butanol and observed that water-soluble natural and synthetic chromophores, as well as dyes generated in biochemical reactions, can be extracted, concentrated, and analyzed spectrophotometrically. Trypan blue and phenol red are used as examples of synthetic dyes, and red wine is used as an example of phenolic plant pigments. Applications for quantification of nitric oxides and sialic acids are described in more detail and show that as little as 0.15 nmol of nitric oxide and 0.20 nmol of sialic acid can be detected. A major advantage of this method is its ability to concentrate chromophores from dye-containing solutions that otherwise cannot be measured because of their low concentrations.


Assuntos
Colorimetria/métodos , Óxido Nítrico/análise , Fenolsulfonaftaleína/isolamento & purificação , Pigmentos Biológicos/isolamento & purificação , Ácidos Siálicos/análise , Azul Tripano/isolamento & purificação , Álcoois/química , Detergentes/química , Fenolsulfonaftaleína/química , Pigmentos Biológicos/química , Solubilidade , Azul Tripano/química
6.
Transfus Med Rev ; 21(2): 164-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17489141

RESUMO

Doctor Parviz Lalezari, currently a clinical professor of Medicine and Pathology at Albert Einstein College of Medicine in New York, describes highlights of his research career since 1958. He became the director of the blood bank at Montefiore Hospital in New York City in 1961, director of the Division of Immunohematology until 1996, and then until 2001, was President and chief executive officer of the Bergen Community Regional Blood Center in New Jersey. Doctor Lalezari was born in Iran in 1931, and after graduation from Medical School, he came to the United States in 1956. His initial research was on leukocyte antibodies. After modifying the available antibody detection techniques, he discovered that like hemolytic disease of the newborn and neonatal immune thrombocytopenia, fetal-maternal neutrophil incompatibility can cause neonatal neutropenia. He identified the targets of these antibodies and showed that they were expressed only on peripheral blood neutrophils. Doctor Lalezari also discovered that a common form of neutropenia in early childhood was caused by development of autoantibodies, which surprisingly were directed against the same neutrophil-specific antigens involved in fetal-maternal incompatibility. In 1959, a heparin-neutralizing drug (Polybrene) was introduced to be used after open-heart surgery. Lalezari discovered that Polybrene, a quaternary ammonium polymer, reacted with sialic acid molecules on the red blood cell (RBC) surface, causing the RBCs to aggregate. Later, realizing that the repelling forces generated by the RBC surface membrane charges were responsible for failure of the small IgG antibody molecules to agglutinate the RBCs, he used Polybrene to neutralize the RBC surface negative charge to allow the IgG antibody molecules to induce hemagglutination. This became The Polybrene test, which is to be used in RBC antibody detection.


Assuntos
Autoanticorpos , Agregação Eritrocítica , Leucócitos , Púrpura Trombocitopênica Idiopática , Sangramento por Deficiência de Vitamina K , Autoanticorpos/história , Autoanticorpos/imunologia , Agregação Eritrocítica/imunologia , Antagonistas de Heparina/química , Antagonistas de Heparina/história , Brometo de Hexadimetrina/química , Brometo de Hexadimetrina/história , História do Século XX , História do Século XXI , Humanos , Recém-Nascido , Leucócitos/imunologia , Púrpura Trombocitopênica Idiopática/história , Púrpura Trombocitopênica Idiopática/imunologia , Sangramento por Deficiência de Vitamina K/história , Sangramento por Deficiência de Vitamina K/imunologia
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