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1.
Braz. j. biol ; 81(4): 1030-1035, Oct.-Dec. 2021. tab, graf
Article in English | LILACS | ID: biblio-1153419

ABSTRACT

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.


Subject(s)
Animals , Arthropods , Soil Pollutants , Soil , Sheep , Avena , Growth and Development , Manure
2.
Braz J Biol ; 81(4): 1030-1035, 2021.
Article in English | MEDLINE | ID: mdl-33084737

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.


Subject(s)
Arthropods , Soil Pollutants , Animals , Avena , Growth and Development , Manure , Sheep , Soil
3.
ACS Appl Mater Interfaces ; 12(5): 6752-6760, 2020 Feb 05.
Article in English | MEDLINE | ID: mdl-31927947

ABSTRACT

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.

5.
Phys Rev Lett ; 121(14): 147203, 2018 Oct 05.
Article in English | MEDLINE | ID: mdl-30339435

ABSTRACT

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.

6.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467516

ABSTRACT

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.

7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(2 Pt 2): 026603, 2012 Aug.
Article in English | MEDLINE | ID: mdl-23005872

ABSTRACT

We derive the complex Ginzburg-Landau equation for the dynamical self-diffraction of optical waves in a nonlinear cavity. The case of the reflection geometry of wave interaction as well as a medium that possesses the cubic nonlinearity (including a local and a nonlocal nonlinear responses) and the relaxation is considered. A stable localized spatial structure in the form of a "dark" dissipative soliton is formed in the cavity in the steady state. The envelope of the intensity pattern, as well as of the dynamical grating amplitude, takes the shape of a tanh function. The obtained complex Ginzburg-Landau equation describes the dynamics of this envelope; at the same time, the evolution of this spatial structure changes the parameters of the output waves. New effects are predicted in this system due to the transformation of the dissipative soliton which takes place during the interaction of a pulse with a continuous wave, such as retention of the pulse shape during the transmission of impulses in a long nonlinear cavity, and giant amplification of a seed pulse, which takes energy due to redistribution of the pump continuous energy into the signal.

8.
Minerva Med ; 102(3): 239-47, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21593724

ABSTRACT

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.


Subject(s)
Arrhythmias, Cardiac , Sports , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/etiology , Arrhythmias, Cardiac/therapy , Electrocardiography/methods , Exercise/physiology , Humans , Sports/physiology
9.
Article in English | MEDLINE | ID: mdl-24785501

ABSTRACT

Patulin is a mycotoxin produced by fungi belonging to the Penicillium and Aspergillus genera. The occurrence of patulin in fruit juices marketed in Italy in 2008 and purchased from supermarkets and retail shops has been measured. The aim of this study was to assess the presence of patulin in order to evaluate the potential risk for the consumer and, at the end of this food chain, to determine the quality of the raw material used. One hundred and five fruit juices (35 apple juice, 35 mixed-taste juices, 35 pear juices), produced by various Italian and European companies, were analysed using a previously published method. The analytical investigation showed that apple juices had a concentration of patulin ranging between 6 and 30 µg l(-1), with a mean of 18 µg l(-1); mixed fruit juices had a concentration ranging between 1 and 45 µg l(-1), with a mean of 23 µg l(-1). Instead, pear juices had a concentration ranging between 5 and 92 µg l(-1), with a mean of 43 µg l(-1), and 14 samples of the 35 analysed juices showed a patulin level above the highest regulated limit of 50 µg l(-1), imposed by European Commission Regulation 1881/06.


Subject(s)
Diet , Environmental Exposure/analysis , Food Contamination/analysis , Fruit/chemistry , Malus/microbiology , Patulin/analysis , Pyrus/microbiology , Beverages , Data Collection , Fruit/microbiology , Fungi , Humans
11.
Aliment Pharmacol Ther ; 27(10): 932-9, 2008 May.
Article in English | MEDLINE | ID: mdl-18315586

ABSTRACT

BACKGROUND: Bone marrow-derived stem cells (BMSC) and granulocyte colony-stimulating factor (G-CSF) have been proved to contribute to tissue regeneration after liver injury. AIMS: To test the safety of G-CSF and define the exact dose capable of mobilizing BMSC in the majority of patients with liver cirrhosis; and to assess the feasibility of leukapheresis to collect BMSC from peripheral blood. METHODS: In this study, we treated 18 patients affected by liver cirrhosis with increasing doses of G-CSF to mobilize CD34(+) and CD133(+) BMSC into the peripheral blood. RESULTS: The dose-finding phase demonstrated that 15 microg/kg/day of G-CSF is the optimal dose to mobilize both CD34(+) and CD133(+) stem cells. Circulating BMSC were collected by a single step leukapheresis in three patients and the mean number of CD34(+) and CD133(+) cells cryopreserved was 1.3 +/- 0.7 and 1.2 +/- 0.5 x 10(6)/kg, respectively. No severe adverse events were observed during the drug administration and stem cell collection. Noteworthy is, none of the patients showed a significant modification of liver function. CONCLUSIONS: Our study demonstrates that G-CSF administration and BMSC collection from the peripheral blood is possible and safe in patients with liver cirrhosis. The optimal dose to mobilize BMSC in cirrhotics is 15 microg/kg/day. At this dose, G-CSF does not seem to modify the residual liver function in cirrhotic patients.


Subject(s)
Granulocyte Colony-Stimulating Factor/administration & dosage , Hematopoietic Stem Cell Mobilization/methods , Leukapheresis/methods , Liver Cirrhosis/therapy , Peripheral Blood Stem Cell Transplantation/methods , AC133 Antigen , Adult , Aged , Antigens, CD , Antigens, CD34 , Dose-Response Relationship, Drug , Feasibility Studies , Female , Glycoproteins , Granulocyte Colony-Stimulating Factor/adverse effects , Humans , Male , Middle Aged , Peptides , Treatment Outcome
12.
Leukemia ; 21(3): 427-38, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17215852

ABSTRACT

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.


Subject(s)
Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Leukemic/physiology , Leukemia, Myeloid/pathology , Multidrug Resistance-Associated Proteins/biosynthesis , Phosphatidylinositol 3-Kinases/physiology , Proto-Oncogene Proteins c-akt/physiology , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Acute Disease , Adult , Aged , Aged, 80 and over , Androstadienes/pharmacology , Bone Neoplasms/pathology , Cell Line, Tumor/drug effects , Cell Line, Tumor/metabolism , Female , Fluorescent Dyes/metabolism , Gene Expression Regulation, Leukemic/drug effects , Gene Expression Regulation, Leukemic/genetics , Genes, p53 , Humans , Jurkat Cells/drug effects , Jurkat Cells/metabolism , Leukemia, Myeloid/genetics , Leukemia, Myeloid/metabolism , Leukemia, Promyelocytic, Acute/pathology , Leukemia-Lymphoma, Adult T-Cell/pathology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Male , Middle Aged , Multidrug Resistance-Associated Proteins/genetics , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/metabolism , Osteosarcoma/pathology , Phosphoinositide-3 Kinase Inhibitors , Phosphorylation , Protein Processing, Post-Translational , Proto-Oncogene Proteins c-mdm2/biosynthesis , Proto-Oncogene Proteins c-mdm2/genetics , Rhodamine 123/metabolism , Tumor Suppressor Protein p53/biosynthesis , Wortmannin
13.
Cell Tissue Bank ; 8(3): 195-203, 2007.
Article in English | MEDLINE | ID: mdl-17063259

ABSTRACT

This study was aimed to establish whether the cryopreservation procedure we currently use in clinics can modify arterial homograft antigenicity. To this purpose, we performed an immunohistochemical study on fresh and cryopreserved human arterial homografts to visualize the expression of HLA class I heavy and light chains "in situ" by using the HC-10 and Namb-1 monoclonal antibodies. Human femoral arteries and thoracic aortas were harvested from 18 heart-beating donors and sampled before and after cryopreservation. Arterial segments were frozen in liquid nitrogen vapors in a controlled rate freezing system. After thawing, samples were processed for routine immunohistochemistry. To standardize immunostaining, flow-cytometry indirect immunofluorescence analysis was performed on HUVEC; immunohistochemistry of human ovarian cortical vessels was performed as an additional positive control. Negative controls were performed by omitting tissue incubation with primary antibodies. HLA-class I antigens were markedly expressed by endothelial cells lining surface intima and adventitial vasa vasorum; a moderate expression was found in medial smooth muscle cells. Except for the surface unreactivity caused by loss of endothelium, results from cryopreserved arterial allografts were strictly comparable to those observed in fresh, unfrozen tissues. These results support the view that cryopreserved arterial allografts are immunogenic as their fresh counterparts; apart from smooth muscle cells which retained a moderate expression of HLA class I antigens following cryopreservation, our study suggests that the highly HC-10 positive endothelial cells we found to line the rich adventitial network of vasa vasorum are expected to be one of the major targets of the serological response in the recipient.


Subject(s)
Arteries/immunology , Arteries/transplantation , Cryopreservation , HLA Antigens/immunology , Adult , Antibodies, Monoclonal/immunology , Female , Flow Cytometry , Humans , Immunohistochemistry , Male , Transplantation, Homologous
14.
J Comput Chem ; 28(2): 584-93, 2007 Jan 30.
Article in English | MEDLINE | ID: mdl-17186475

ABSTRACT

Metal clusters described in the framework of a simple tight binding model have been studied. Application of a dynamical approach (FOM), jointly with efficient storage of the sparse Hamiltonian matrix involved, is shown to allow direct evaluation of the electronic state density of sizable cubic-symmetry aggregates.


Subject(s)
Metals/chemistry , Models, Chemical , Quantum Theory , Computer Simulation , Electrons , Nanostructures/chemistry , Oscillometry/methods
15.
J Transl Med ; 4: 44, 2006 Oct 27.
Article in English | MEDLINE | ID: mdl-17069649

ABSTRACT

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.

17.
Cryobiology ; 52(2): 309-16, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16458877

ABSTRACT

The cryopreservation protocol we use for arterial reconstructive surgery has been studied to evaluate smooth muscle cell (SMC) structural integrity and viability before implantation. Samples of human thoracic aortas (HTA) were harvested from five multi-organ donors. Sampling included unfrozen and cryopreserved specimens. Cryopreservation was performed using RPMI with human albumin and 10% Me(2)SO in a controlled-rate freezing apparatus. Thawing was accomplished by submerging bags in a water bath (39 degrees C) followed by washings in cooled saline. In situ cell preservation as investigated by light and transmission electron microscopy showed that SMCs from cryopreserved HTA had nuclear and cytoplasmic changes. A TUNEL assay, performed to detect DNA fragmentation in situ, showed increased SMC nuclear positivity in cryopreserved HTA when compared to unfrozen samples. 7-AAD flow cytometry assay of cells derived from cryopreserved HTA showed that an average of 49+/-16% cells were unlabeled after cryopreservation. Organ cultures aimed to study cell ability to recover cryopreservation damage showed a decreasing number of SMCs from day 4 to day 15 in cryopreserved HTA. In conclusion, the cryopreservation protocol applied in this study induces irreversible damage of a significant fraction of arterial SMCs.


Subject(s)
Aorta, Thoracic , Cryopreservation , Myocytes, Smooth Muscle/pathology , Organ Preservation , Tissue Survival , Aorta, Thoracic/injuries , Cryoprotective Agents/chemistry , Humans , In Situ Nick-End Labeling , Microscopy, Electron, Transmission , Organ Culture Techniques
18.
Transfus Med ; 15(5): 443-4, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16202061

ABSTRACT

Anti-human platelet antigens (HPA) alloantibodies are seldom involved in febrile nonhaemolytic reactions (FNHTRs). We describe a case in which anti-HPA-5a alloantibodies are related to an FNHTR. We studied the specificity of the alloantibodies by flow cytometry, ELISA and MACE. Typing of donors and the patient was performed by sequence-specific polymerase chain reaction. The alloantibodies were found reactive with HPA-5a antigens. The patient was HPA-5b/b, whereas the donor of the platelet apheresis involved in the FNHTR was HPA-5a/a. Despite the low frequency of anti-HPA-5a antibodies, they might be responsible for FNHTR.


Subject(s)
Antigens, Human Platelet , Blood Donors , Isoantibodies , Platelet Transfusion , Thrombocytopenia , Adult , Antigens, Human Platelet/immunology , Female , Hemolysis/immunology , Humans , Isoantibodies/genetics , Isoantibodies/immunology , Platelet Transfusion/adverse effects , Platelet Transfusion/methods , Thrombocytopenia/therapy
19.
Transplant Proc ; 37(6): 2428-9, 2005.
Article in English | MEDLINE | ID: mdl-16182699

ABSTRACT

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.


Subject(s)
Blood Vessels/transplantation , Tissue Banks/trends , Tissue Donors , Adolescent , Adult , Brain Death , Cryopreservation , Humans , Italy , Middle Aged , Organ Preservation , Tissue and Organ Harvesting/methods , Transplantation, Homologous/methods , Vascular Surgical Procedures
20.
Transplant Proc ; 37(6): 2688-91, 2005.
Article in English | MEDLINE | ID: mdl-16182785

ABSTRACT

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.


Subject(s)
Arteries/transplantation , Cryopreservation/methods , Transplantation, Homologous/methods , Vascular Diseases/surgery , ABO Blood-Group System , Aged , Blood Group Incompatibility , Follow-Up Studies , HLA Antigens/immunology , Histocompatibility Testing , Humans , Immunosuppressive Agents/therapeutic use , Infections/surgery , Male , Middle Aged , Prospective Studies , Tissue and Organ Harvesting/methods , Transplantation, Homologous/immunology
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