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1.
Phys Rev Lett ; 121(14): 147203, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30339435

RESUMO

We measure and analyze the chirality of Dzyaloshinskii-Moriya-interaction (DMI) stabilized spin textures in multilayers of Ta|Co_{20}F_{60}B_{20}|MgO. The effective DMI is measured experimentally using domain wall motion measurements, both in the presence (using spin-orbit torques) and absence of driving currents (using magnetic fields). We observe that the current-induced domain wall motion yields a change in effective DMI magnitude and opposite domain wall chirality when compared to field-induced domain wall motion (without current). We explore this effect, which we refer to as current-induced DMI, by providing possible explanations for its emergence, and explore the possibility of its manifestation in the framework of recent theoretical predictions of DMI modifications due to spin currents.

3.
Minerva Med ; 102(3): 239-47, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21593724

RESUMO

Rhythm disorders represent the main challenge for the sport physician and cardiologist to grant the certificate of sports eligibility to the athletes. Arrhythmias that occur in athletes can be divided into two types. The most common are generally an expression of morphofunctional changes in the athlete's heart and are represented by certain forms of non-complex tachyarrhythmias and bradyarrhythmias. On the other hand you may encounter less frequently more complex arrhythmias that may be an epiphenomenon of cardiomyopathy can cause sudden death during sports activities. By collection of detailed medical history, careful examination, and in particular by the 12-lead electrocardiogram is already possible to understand the arrhythmic risk sporting population. After an analysis of main types of arrhythmias encountered in the athlete and the main diagnostic methods, this study focuses on the interplay between forms of arrhythmias, arrhythmogenic heart diseases and activity sports. Surely the increased adrenergic tone and anatomical and functional alterations sports-related favor the development of arrhythmia and sudden death risk in structural cardiomyopathies. But this is not yet resolved the question of whether sport is able to increase the incidence of ventricular arrhythmias in a normal heart. Dangerousness of the arrhythmia is variable depending on the sport is practiced with high intensity or not. Even if it is important considering the possibility of syncope in hazardous environments. Arrhythmias at risk impose the exclusion of the athlete from the practice of sport. In some cases it may be considered a drug treatment, ablation, and in rare and selected cases, the implantation of a pacemaker or an implantable defibrillator.


Assuntos
Arritmias Cardíacas , Esportes , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/terapia , Eletrocardiografia/métodos , Exercício Físico/fisiologia , Humanos , Esportes/fisiologia
4.
Braz J Biol ; 81(4): 1030-1035, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33084737

RESUMO

The aim of this study was to evaluate the effects of sheep manure in agricultural soils on the behavior of Folsomia candida and initial growth and development of Avena sativa. For this, an Oxisol was submitted to different doses of sheep manure and was subsequently evaluated for Folsomia candida survival and avoidance behavior through standardized ecotoxicological assays, the initial performance of oats by germination test and the soil basal respiration rate by respirometry methodology. There was an increase in the basal respiration rate of the soil by the application of sheep manure and this was consistent with the increase of the doses. The survival rate and avoidance behavior of springtails were not altered and there was no change in the initial performance of oats, indicating that this manure can be used for organic fertilization of soils with low soil pollutant potential.


Assuntos
Artrópodes , Poluentes do Solo , Animais , Avena , Crescimento e Desenvolvimento , Esterco , Ovinos , Solo
5.
J Exp Med ; 182(2): 605-9, 1995 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-7629517

RESUMO

Natural killer (NK) cells have been shown to express a clonally distributed ability to recognize HLA class I alleles. The previously defined NK clones belonging to "group 1" recognize HLA-C*0401 (Cw4) and other HLA-C alleles sharing Asn at position 77 and Lys at position 80. Conversely, the "group 2" NK clones recognize HLA-Cw*0302 (Cw3) and other HLA-C alleles characterized by Ser at position 77 and Asn at position 80. We assessed directly the involvement of these two residues in the capacity of NK cell clones to discriminate between the two groups of HLA-C alleles. To this end, Cw3 and Cw4 alleles were subjected to site-directed mutagenesis. Substitution of the amino acids typical of the Cw3 allele (Ser-77 and Asn-80) with those present in Cw4 (Asn-77 and Lys-80) resulted in a Cw3 mutant that was no longer recognized by group 2 NK cell clones, but that was recognized by group 1 clones. Analysis of Cw3 or Cw4 molecules containing single amino acid substitutions indicates roles for Lys-80 in recognition mediated by group 1 clones and for Ser-77 in recognition mediated by group 2 clones. These results demonstrate that NK-mediated specific recognition of HLA-C allotypes is affected by single natural amino acid substitutions at positions 77 and 80 of the heavy chain.


Assuntos
Antígenos HLA-C/imunologia , Células Matadoras Naturais/imunologia , Sequência de Aminoácidos , Sequência de Bases , Células Cultivadas , Citotoxicidade Imunológica , Primers do DNA/química , Antígenos HLA-C/química , Humanos , Imunidade Celular , Técnicas In Vitro , Dados de Sequência Molecular , Relação Estrutura-Atividade
6.
J Exp Med ; 183(2): 645-50, 1996 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8627176

RESUMO

Natural killer cells express clonally distributed receptors specific for major histocompatibility complex class I molecules. The human leukocyte antigen (HLA)-C-specific receptors have been molecularly identified and cloned. They exist not only as inhibitory (p58) but also as activatory (p50) receptors. Here we show that p50 and p58 are highly homologous in their extracellular regions formed by two Ig-like domains. In contrast, major differences exist in their transmembrane and cytoplasmic portions. Whereas p 58 displays a 76-84-amino acid cytoplasmic tail containing an unusual antigen receptor activation motif, p50 is characterized by a shorter 39-amino acid tail. In addition, whereas p58 has a nonpolar transmembrane portion, p50 contains the charged amino acid Lys. These data strongly suggest that receptors with identical HLA-C allele specificity can mediate functions of opposite sign owing to their different transmembrane/cytoplasmic portions.


Assuntos
Antígenos HLA-C/imunologia , Células Matadoras Naturais/imunologia , Receptores Imunológicos/genética , Transdução de Sinais , Sequência de Aminoácidos , Sequência de Bases , Células Clonais , DNA Complementar/genética , Citometria de Fluxo , Humanos , Dados de Sequência Molecular , Conformação Proteica , Receptores Imunológicos/biossíntese , Receptores KIR , Receptores KIR2DL3 , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade , Transfecção
7.
ACS Appl Mater Interfaces ; 12(5): 6752-6760, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31927947

RESUMO

The magnetoelectric properties of exchange-coupled Ni/CoFeB-based composite multiferroic microstructures are investigated. The strength and sign of the magnetoelastic effect are found to be strongly correlated with the ratio between the thicknesses of two magnetostrictive materials. In cases where the thickness ratio deviates significantly from one, the magnetoelastic behavior of the multiferroic microstructures is dominated by the thicker layer, which contributes more strongly to the observed magnetoelastic effect. More symmetric structures with a thickness ratio equal to one show an emergent interfacial behavior which cannot be accounted for simply by summing up the magnetoelastic effects occurring in the two constituent layers. This aspect is clearly visible in the case of ultrathin bilayers, where the exchange coupling drastically affects the magnetic behavior of the Ni layer, making the Ni/CoFeB bilayer a promising next-generation synthetic magnetic system entirely. This study demonstrates the richness and high tunability of composite multiferroic systems based on coupled magnetic bilayers compared to their single magnetic layer counterparts. Furthermore, because of the compatibility of CoFeB with present magnetic tunnel junction-based spintronic technologies, the reported findings are expected to be of great interest for the development of ultralow-power magnetoelectric memory devices.

8.
Leukemia ; 21(3): 427-38, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17215852

RESUMO

A high incidence of relapses following induction chemotherapy is a major hindrance to patient survival in acute myelogenous leukemia (AML). There is strong evidence that activation of the phosphoinositide 3 kinase (PI3K)/Akt signaling network plays a significant role in rendering AML blasts drug resistant. An important mechanism underlying drug resistance is represented by overexpression of membrane drug transporters such as multidrug resistance-associated protein 1 (MRP1) or 170-kDa P-glycoprotein (P-gp). Here, we present evidence that MRP1, but not P-gp, expression is under the control of the PI3K/Akt axis in AML blasts. We observed a highly significant correlation between levels of phosphorylated Akt and MRP1 expression in AML cells. Furthermore, incubation of AML blasts with wortmannin, a PI3K pharmacological inhibitor, resulted in lower levels of phosphorylated Akt, downregulated MRP1 expression, and decreased Rhodamine 123 extrusion in an in vitro functional dye efflux assay. We also demonstrate that wortmannin-dependent PI3K/Akt inhibition upregulated p53 protein levels in most AML cases, and this correlated with diminished MRP1 expression and enhanced phosphorylation of murine double minute 2 (MDM2). Taken together, these data suggest that PI3K/Akt activation may lead to the development of chemoresistance in AML blasts through a mechanism involving a p53-dependent suppression of MRP1 expression.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Regulação Leucêmica da Expressão Gênica/fisiologia , Leucemia Mieloide/patologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/biossíntese , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Androstadienos/farmacologia , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/metabolismo , Feminino , Corantes Fluorescentes/metabolismo , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/genética , Genes p53 , Humanos , Células Jurkat/efeitos dos fármacos , Células Jurkat/metabolismo , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Leucemia Promielocítica Aguda/patologia , Leucemia-Linfoma de Células T do Adulto/patologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Osteossarcoma/patologia , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-mdm2/biossíntese , Proteínas Proto-Oncogênicas c-mdm2/genética , Rodamina 123/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Wortmanina
9.
J Transl Med ; 4: 44, 2006 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-17069649

RESUMO

BACKGROUND: Killer cell immunoglobulin-like receptors (KIRs) are a family of inhibitory and activatory receptors that are expressed by most natural killer (NK) cells. The KIR gene family is polymorphic: genomic diversity is achieved through differences in gene content and allelic polymorphism. The number of KIR loci has been reported to vary among individuals, resulting in different KIR haplotypes. In this study we report the genotypic structure of KIRs in 217 unrelated healthy Italian individuals from 22 immunogenetics laboratories, located in the northern, central and southern regions of Italy. METHODS: Two hundred and seventeen DNA samples were studied by a low resolution PCR-SSP kit designed to identify all KIR genes. RESULTS: All 17 KIR genes were observed in the population with different frequencies than other Caucasian and non-Caucasian populations; framework genes KIR3DL3, KIR3DP1, KIR2DL4 and KIR3DL2 were present in all individuals. Sixty-five different profiles were found in this Italian population study. Haplotype A remains the most prevalent and genotype 1, with a frequency of 28.5%, is the most commonly observed in the Italian population. CONCLUSION: The Italian Caucasian population shows polymorphism of the KIR gene family like other Caucasian and non-Caucasian populations. Although 64 genotypes have been observed, genotype 1 remains the most frequent as already observed in other populations. Such knowledge of the KIR gene distribution in populations is very useful in the study of associations with diseases and in selection of donors for haploidentical bone marrow transplantation.

10.
Braz. j. biol ; Braz. j. biol;81(4): 1030-1035, Oct.-Dec. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153419

RESUMO

Abstract The aim of this study was to evaluate the effects of sheep manure in agricultural soils on the behavior of Folsomia candida and initial growth and development of Avena sativa. For this, an Oxisol was submitted to different doses of sheep manure and was subsequently evaluated for Folsomia candida survival and avoidance behavior through standardized ecotoxicological assays, the initial performance of oats by germination test and the soil basal respiration rate by respirometry methodology. There was an increase in the basal respiration rate of the soil by the application of sheep manure and this was consistent with the increase of the doses. The survival rate and avoidance behavior of springtails were not altered and there was no change in the initial performance of oats, indicating that this manure can be used for organic fertilization of soils with low soil pollutant potential.


Resumo O objetivo deste estudo foi avaliar os efeitos do esterco de ovelha em solos agrícolas no comportamento de Folsomia candida e no crescimento e desenvolvimento inicial de Avena sativa. Para isso, um Latossolo foi submetido a diferentes doses de esterco de ovelha e posteriormente avaliado quanto ao comportamento de fuga e a sobrevivência de Folsomia candida por meio de ensaios ecotoxicológicos padronizados, desempenho inicial da aveia pelo teste de germinação e taxa respiratória basal do solo pela metodologia da respirometria. Houve um aumento na taxa de respiração basal do solo pela aplicação de esterco de ovelha e isso foi consistente com o aumento das doses. A taxa de sobrevivência e o comportamento de fuga dos colêmbolos não foram alterados e não houve alteração no desempenho inicial da aveia, indicando que esse esterco pode ser usado para fertilização orgânica de solos com baixo potencial poluente no solo.


Assuntos
Animais , Artrópodes , Poluentes do Solo , Solo , Ovinos , Avena , Crescimento e Desenvolvimento , Esterco
11.
Bone Marrow Transplant ; 36(4): 289-94, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15968277

RESUMO

Healthy allogeneic donors, who were treated with G-CSF and underwent peripheral blood haematopoietic precursor collection at our Institution, were enrolled in a short- and long-term haematological surveillance protocol for a 5--7--year period. To date, 94 donors have been assessed with a mean follow-up of 30 months (4--84); for 30 subjects, the follow-up is >or=48 months. During G-CSF administration, 23/94 donors showed a significant platelet count decrease from the baseline. Pre-apheresis platelet decrement correlated with the total G-CSF dose administered, baseline platelet level and donor age. Normal platelet counts returned within 4--8 months. PMN and/or lymphocyte lower values were observed in 55/94 donors 2 weeks after G-CSF administration, with mean drops from the baseline of 40 and 36% for PMN and lymphocytes, respectively. The PMN decrease correlated inversely with donor age, as younger donors were more affected than older ones, whereas the lymphocyte decrease correlated directly with the total blood volumes processed in the apheresis courses, in particular for donors subjected to large volume leukaphereses. Long-term observation showed moderate neutrophil reduction (25% count drop from the baseline) in four of the 30 donors observed for four years or more. 14 donors showed persistent, slight lymphocytopenia (mean drop of 13%) until the third year, with recovery in the fourth year of follow-up.


Assuntos
Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Leucaférese , Vigilância da População , Doadores de Tecidos , Adulto , Fatores Etários , Contagem de Células Sanguíneas , Feminino , Seguimentos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Contagem de Linfócitos , Linfopenia/etiologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Transplante de Células-Tronco de Sangue Periférico , Contagem de Plaquetas , Estudos Prospectivos , Fatores de Tempo , Transplante Homólogo
12.
Leukemia ; 17(9): 1794-805, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12970779

RESUMO

It is now well established that the reduced capacity of tumor cells of undergoing cell death through apoptosis plays a key role both in the pathogenesis of cancer and in therapeutic treatment failure. Indeed, tumor cells frequently display multiple alterations in signal transduction pathways leading to either cell survival or apoptosis. In mammals, the pathway based on phosphoinositide 3-kinase (PI3K)/Akt conveys survival signals of extreme importance and its downregulation, by means of pharmacological inhibitors of PI3K, considerably lowers resistance to various types of therapy in solid tumors. We recently described an HL60 leukemia cell clone (HL60AR cells) with a constitutively active PI3K/Akt pathway. These cells were resistant to multiple chemotherapeutic drugs, all-trans-retinoic acid (ATRA), and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Treatment with two pharmacological inhibitors of PI3K, wortmannin and Ly294002, restored sensitivity of HL60AR cells to the aforementioned treatments. However, these inhibitors have some drawbacks that may severely limit or impede their clinical use. Here, we have tested whether or not a new selective Akt inhibitor, 1L-6-hydroxymethyl-chiro-inositol 2(R)-2-O-methyl-3-O-octadecylcarbonate (Akt inhibitor), was as effective as Ly294002 in lowering the sensitivity threshold of HL60 cells to chemotherapeutic drugs, TRAIL, ATRA, and ionizing radiation. Our findings demonstrate that, at a concentration which does not affect PI3K activity, the Akt inhibitor markedly reduced resistance of HL60AR cells to etoposide, cytarabine, TRAIL, ATRA, and ionizing radiation. This effect was likely achieved through downregulation of expression of antiapoptotic proteins such as c-IAP1, c-IAP2, cFLIP(L), and of Bad phosphorylation on Ser 136. The Akt inhibitor did not influence PTEN activity. At variance with Ly294002, the Akt inhibitor did not negatively affect phosphorylation of protein kinase C-zeta and it was less effective in downregulating p70S6 kinase (p70S6K) activity. The Akt inhibitor increased sensitivity to apoptotic inducers of K562 and U937, but not of MOLT-4, leukemia cells. Overall, our results indicate that selective Akt pharmacological inhibitors might be used in the future for enhancing the sensitivity of leukemia cells to therapeutic treatments that induce apoptosis or for overcoming resistance to these treatments.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Inositol/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Tretinoína/farmacologia , Western Blotting , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD , Proteínas de Transporte/metabolismo , Caspases/metabolismo , Cromonas/farmacologia , Citarabina/farmacologia , Grupo dos Citocromos c/metabolismo , Inibidores Enzimáticos/farmacologia , Etoposídeo/farmacologia , Células HL-60/efeitos dos fármacos , Células HL-60/efeitos da radiação , Humanos , Proteínas Inibidoras de Apoptose , Inositol/análogos & derivados , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Morfolinas/farmacologia , PTEN Fosfo-Hidrolase , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Proteína Quinase C-theta , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Radiação Ionizante , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transfecção , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases , Proteína de Morte Celular Associada a bcl
13.
Leukemia ; 8(12): 2134-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7808001

RESUMO

CML patients possess either a b3-a2 or a b2-a2 fusion between the BCR and ABL genes. Depending on the type of fusion, two different series of non-self potentially immunogenic peptides may be produced. If they are presented by HLA class I molecules and recognized by cytotoxic CD8 lymphocytes, individuals could be more susceptible or resistant to leukemic cells bearing one or the other form of fusion according to their HLA class I phenotype. To test this point, the frequencies of HLA-A and HLA-B alleles were compared between b3-a2 and the b2-a2 CML patients. In essence, no difference was found whose significance could withstand correction for multiple comparisons.


Assuntos
Proteínas de Fusão bcr-abl/genética , Antígenos HLA/análise , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Cromossomo Filadélfia , Sequência de Bases , Distribuição de Qui-Quadrado , Antígenos HLA-A/análise , Antígenos HLA-B/análise , Humanos , Itália , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
14.
World J Gastroenterol ; 11(46): 7323-9, 2005 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-16437636

RESUMO

AIM: To investigate the single nucleotide polymorphisms (SNPs) in genes involved in bacterial recognition and the susceptibility to pouchitis or pouchitis severity. METHODS: Analyses of CD14 -260C>T, CARD15/NOD2 3020insC, Toll-like receptor (TLR)4 +896A>G, TLR9 -1237T>C, TLR9+2848G>A, and IRAKM + 22148G>A SNPs were performed in 157 ileal-pouch anal anastomosis (IPAA) patients (79 patients who did not develop pouchitis, 43 infrequent pouchitis patients, 35 chronic relapsing pouchitis patients) and 224 Italian Caucasian healthy controls. RESULTS: No significant differences were found in SNP frequencies between controls and IPAA patients. However, a significant difference in carriership frequency of the TLR9-1237C allele was found between the infrequent pouchitis and chronic relapsing pouchitis groups [P = 0.028, oddos ratio (OR) = 3.2, 95%CI = 1.2-8.6]. This allele uniquely represented a 4-locus TLR9 haplotype comprising both studied TLR9 SNPs in Caucasians. Carrier trait analysis revealed an enhanced combined carriership of the alleles TLR9 -1237C and CD14 -260T in the chronic relapsing pouchitis and infrequent pouchitis group (P = 0.018, OR = 4.1, 95%CI = 1.4 -12.3). CONCLUSION: There is no evidence that the SNPs predispose to the need for IPAA surgery. The significant increase of the combined carriership of the CD14 -260T and TLR9 -1237C alleles in the chronic relapsing pouchitis group suggests that these markers identify a subgroup of IPAA patients with a risk of developing chronic or refractory pouchitis.


Assuntos
Receptores de Lipopolissacarídeos/genética , Pouchite/genética , Pouchite/imunologia , Receptor Toll-Like 9/genética , Adulto , Alelos , Sequência de Bases , Estudos de Casos e Controles , Doença Crônica , Bolsas Cólicas/efeitos adversos , DNA/genética , Feminino , Frequência do Gene , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Pouchite/etiologia , Recidiva , Fatores de Risco
15.
Transplant Proc ; 37(6): 2428-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16182699

RESUMO

INTRODUCTION: The cardiovascular homograft banks in Italy were set up in 1994 in Milan (Lombardia) and Treviso (Veneto) and in 2001 in Bologna, Emilia Romagna. In this study we briefly summarize the data from Emilia Romagna Cardiovascular Tissue Bank. MATERIAL AND METHODS: In Emilia Romagna, vascular homografts were harvested from brain-dead multiorgan donors (aged 15-55 years) by a dedicated vascular surgery team. All donors were virologically screened for human immunodeficiency virus (HIV), hepatitis B and C, Treponema pallidum, cytomegalovirus (CMV), and Toxoplasma. After transferring the vascular homografts to Emilia Romagna Cardiovascular Tissue Bank facilities, the arteries were prepared, classified (class III to I), and transferred to an antibiotic-containing solution under a laminar flow cabinet. After the decontamination, all homografts were cryopreserved and stored in the vapour phase of liquid nitrogen. Microbiological tests were performed in all phases of preparation. Samples were routinely taken from 1 vessel and formalin fixed for the histology. Bags with cryopreserved homografts were sent in dry ice to the hospitals when required and thawing protocol of the Bank was included. RESULTS AND CONCLUSIONS: From January 2002 to October 2004, 543 homografts from 125 heart-beating donors were harvested and transferred to Emilia Romagna Cardiovascular Tissue Bank. After preparation, 459 of 543 (85%) were cryopreserved and stored. Vascular homografts classified class I were discarded. Other criteria of rejection were: (1) positive serology, and (2) persistent positive microbiology after decontamination. From March 2002, 333 cryopreserved homografts were assigned to several vascular surgery departments in Italy. The assessment of 3-year activity of Emilia Romagna Cardiovascular Tissue Bank might be used as an indicator of the efficiency of selecting, cryopreserving, and allocating quality-controlled vascular homografts.


Assuntos
Vasos Sanguíneos/transplante , Bancos de Tecidos/tendências , Doadores de Tecidos , Adolescente , Adulto , Morte Encefálica , Criopreservação , Humanos , Itália , Pessoa de Meia-Idade , Preservação de Órgãos , Coleta de Tecidos e Órgãos/métodos , Transplante Homólogo/métodos , Procedimentos Cirúrgicos Vasculares
16.
Transplant Proc ; 37(6): 2688-91, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16182785

RESUMO

INTRODUCTION: This prospective study defined the immunological and clinical results after fresh and cryopreserved arterial homograft replacement due to graft infection. MATERIALS AND METHODS: Thirty patients who underwent ABO-compatible homograft transplantation were studied for anti-human leukocyte antigen (HLA): antibody production and CD3- and CD4- versus CD8-positive lymphocyte subsets. Nine patients (30%) received immunosuppressive treatment with cyclosporine (1 to 3 mg/kg/d). Immunological studies were performed preoperatively, and early (1, 3, 7 days) and late (1, 3, 6, 12, 24, 36, 48 months) during follow-up. Abdominal computed tomography scans were performed postoperatively at 1, 6, 12, 24, 36, and 48 months of follow-up. RESULTS: Preoperatively, antibodies were not detected. Postoperatively, a progressive increase in percent panel reactive antibodies was observed in all patients 1 month after the transplant. There were no difference between fresh and cryopreserved homografts. The antibody response among patients treated with cyclosporine was less pronounced and delayed. Recipient antibodies were directed against donor-specific antigens. During the immediate postoperative period (1, 3, 7 days) there was a slight increase in CD3- and CD4-positive T lymphocytes and a concomitant decrease in the CD8 subset. Later, CD3 and CD4 progressively decreased and the CD8 set increased. Clinically, no patients had signs of recurrent infection upon late follow-up. Four patients died (13%), but only one death was homograft-related (rupture of the graft). At 2-year follow-up, two patients showed stenotic lesions due to chronic rejection. Clinically, no differences were noted between fresh and cryopreserved homografts, or between patients treated with or without cyclosporine. CONCLUSIONS: Fresh and cryopreserved arterial homografts are immunogenic; they induce a strong anti-HLA antibody response, similar to chronic rejection.


Assuntos
Artérias/transplante , Criopreservação/métodos , Transplante Homólogo/métodos , Doenças Vasculares/cirurgia , Sistema ABO de Grupos Sanguíneos , Idoso , Incompatibilidade de Grupos Sanguíneos , Seguimentos , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Humanos , Imunossupressores/uso terapêutico , Infecções/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Coleta de Tecidos e Órgãos/métodos , Transplante Homólogo/imunologia
17.
DNA Res ; 4(3): 249-52, 1997 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-9330913

RESUMO

Phylogenetic divergence of the members of the Pongidae family has been based on genetic evidence. The terminal repeat array (T2AG3) has lately been considered as an additional basis to analyze genomes of highly related species. The recent isolation of subtelomeric DNA probes specific for human (HSA) chromosomes 7q and 14q has prompted us to cross-hybridize them to the chromosomes of the chimpanzee (PTR), gorilla (GGO) and orangutan (PPY) to search for its equivalent locations in the great ape species. Both probes hybridized to the equivalent telomeric sites of the long (q) arms of all three great ape species. Hybridization signals to the 7q subtelomeric DNA sequence probe were observed at the telomeres of HSA 7q, PTR 6q, GGO 6q and PPY 10q, while hybridization signals to the 14q subtelomeric DNA sequence probe were observed at the telomeres of HSA 14q, PTR 15q, GGO 18q and PPY 15q. No hybridization signals to the chromosome 7-specific alpha satellite DNA probe on the centromeric regions of the ape chromosomes were observed. Our observations demonstrate sequence homology of the subtelomeric repeat families D7S427 and D14S308 in the ape chromosomes. An analogous number of subtelomeric repeat units exists in these chromosomes and has been preserved through the course of differentiation of the hominoid species. Our investigation also suggests a difference in the number of alpha satellite DNA repeat units in the equivalent ape chromosomes, possibly derived from interchromosomal transfers and subsequent amplification of ancestral alpha satellite sequences.


Assuntos
Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 7/genética , Hominidae/genética , Telômero/genética , Animais , Mapeamento Cromossômico , Sondas de DNA/genética , Gorilla gorilla/genética , Humanos , Hibridização in Situ Fluorescente/métodos , Pan troglodytes/genética , Pongo pygmaeus/genética
18.
Transplantation ; 54(2): 351-6, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1496546

RESUMO

An immunotoxin containing the B-B10 MoAb, directed against the CD25 determinant, and the ribosome-inactivating protein saporin, inhibits 3H-TdR incorporation in phytohemagglutin, allogeneic-stimulated lymphocytes (primary and secondary mixed-lymphocyte reaction), and in an alloreactive T cell clone. A lower degree of inhibition was obtained with the B-B10 MoAb, which is known to inhibit IL-2 activity, as well as with the unconjugated compounds. These results suggest that the in vivo administration of the conjugate might be a more effective tool in the treatment of patients affected by graft-versus-host disease than B-B10 alone, by inducing an efficient killing of allogeneic-reacting T lymphocytes.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Imunotoxinas , N-Glicosil Hidrolases , Proteínas de Plantas/administração & dosagem , Receptores de Interleucina-2/imunologia , Linfócitos T/imunologia , Células da Medula Óssea , Células-Tronco Hematopoéticas/imunologia , Humanos , Memória Imunológica , Terapia de Imunossupressão/métodos , Técnicas In Vitro , Ativação Linfocitária , Proteínas Inativadoras de Ribossomos Tipo 1 , Saporinas
19.
Pediatrics ; 80(6): 839-44, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3684394

RESUMO

In spite of inadequate laboratory demonstrations of sleep problems in children with attention deficit disorder with hyperactivity, the belief persists that such problems exist. Sleep restlessness is, in fact, one of the criteria in the Diagnostic and Statistical Manual of Mental Disorders, ed 3, definition of attention deficit disorder with hyperactivity, and sleep problems are listed on two major checklists often used for describing the symptoms of this disorder. In a series of three studies, sleep problems were investigated in preschool-aged children with attention deficit disorder relative to control children without the disorder. Results of the first two studies demonstrated clearly that parents of hyperactive children considered their children to have many more sleep problems than did parents of the control children. Parental daily documentation, which is less likely to be affected by reporting bias, was used in the third study. Although the results of the third study supported the finding of increased frequency of night wakings in these children, there was no difference in total sleep time or sleep onset latency between the two groups. Two other significant group differences (enuresis and night sweats) were primarily due to subgroups of children with attention deficit disorder and hyperactivity. The greater number of sleep wakings, which disrupt parents' sleep, may be responsible for the clinical reports that these children are poor sleepers.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtornos do Sono-Vigília/etiologia , Criança , Pré-Escolar , Ritmo Circadiano , Feminino , Humanos , Masculino , Sudorese , Transtornos Urinários/complicações
20.
Pediatrics ; 83(1): 7-17, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2909977

RESUMO

A 10-week study was conducted in which all food was provided for the families of 24 hyperactive preschool-aged boys whose parents reported the existence of sleep problems or physical signs and symptoms. A within-subject crossover design was used, and the study was divided into three periods: a baseline period of 3 weeks, a placebo-control period of 3 weeks, and an experimental diet period of 4 weeks. The experimental diet was broader than those studied previously in that it eliminated not only artificial colors and flavors but also chocolate, monosodium glutamate, preservatives, caffeine, and any substance that families reported might affect their specific child. The diet was also low in simple sugars, and it was dairy free if the family reported a history of possible problems with cow's milk. According to the parental report, more than half of the subjects exhibited a reliable improvement in behavior and negligible placebo effects. In addition, several nonbehavioral variables tended to improve while the children received the experimental diet, particularly halitosis, night awakenings, and latency to sleep onset.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/dietoterapia , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Pré-Escolar , Halitose/complicações , Halitose/dietoterapia , Humanos , Masculino , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/dietoterapia
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