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1.
Int J Immunogenet ; 49(1): 22-29, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34555264

RESUMO

All UK H&I laboratories and transplant units operate under a single national kidney offering policy, but there have been variations in approach regarding when to undertake the pre-transplant crossmatch test. In order to minimize cold ischaemia times for deceased donor kidney transplantation we sought to find ways to be able to report a crossmatch result as early as possible in the donation process. A panel of experts in transplant surgery, nephrology, specialist nursing in organ donation and H&I (all relevant UK laboratories represented) assessed evidence and opinion concerning five factors that relate to the effectiveness of the crossmatch process, as follows: when the result should be ready for reporting; what level of donor HLA typing is needed; crossmatch sample type and availability; fairness and equity; risks and patient safety. Guidelines aimed at improving practice based on these issues are presented, and we expect that following these will allow H&I laboratories to contribute to reducing CIT in deceased donor kidney transplantation.


Assuntos
Transplante de Rim , Tipagem e Reações Cruzadas Sanguíneas , Isquemia Fria , Antígenos HLA , Teste de Histocompatibilidade , Humanos , Rim
2.
Am J Transplant ; 14(1): 133-43, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24354873

RESUMO

In this study, we analyze the outcomes of transplant renal artery stenosis (TRAS), determine the different anatomical positions of TRAS, and establish cardiovascular and immunological risk factors associated with its development. One hundred thirty-seven of 999 (13.7%) patients had TRAS diagnosed by angiography; 119/137 (86.9%) were treated with angioplasty, of which 113/137 (82.5%) were stented. Allograft survival in the TRAS+ intervention, TRAS+ nonintervention and TRAS- groups was 80.4%, 71.3% and 83.1%, respectively. There was no difference in allograft survival between the TRAS+ intervention and TRAS- groups, p = 0.12; there was a difference in allograft survival between the TRAS- and TRAS+ nonintervention groups, p < 0.001, and between the TRAS+ intervention and TRAS+ nonintervention groups, p = 0.037. TRAS developed at the anastomosis, within a bend/kink or distally. Anastomotic TRAS developed in living donor recipients; postanastomotic TRAS (TRAS-P) developed in diabetic and older patients who received grafts from deceased, older donors. Compared with the TRAS- group, patients with TRAS-P were more likely to have had rejection with arteritis, odds ratio (OR): 4.83 (1.47-15.87), p = 0.0095, and capillaritis, OR: 3.03 (1.10-8.36), p = 0.033. Patients with TRAS-P were more likely to have developed de novo class II DSA compared with TRAS- patients hazard ratio: 4.41 (2.0-9.73), p < 0.001. TRAS is a heterogeneous condition with TRAS-P having both alloimmune and traditional cardiovascular risk factors.


Assuntos
Anticorpos/análise , Antígenos de Histocompatibilidade Classe II/imunologia , Transplante de Rim/efeitos adversos , Obstrução da Artéria Renal/imunologia , Doadores de Tecidos , Adulto , Idoso , Angiografia Digital/efeitos adversos , Feminino , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução da Artéria Renal/diagnóstico , Obstrução da Artéria Renal/cirurgia , Fatores de Risco , Stents , Resultado do Tratamento
3.
Am J Transplant ; 13(2): 485-92, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23167441

RESUMO

In renal transplant patients with de novo donor-specific antibodies (dnDSA) we studied the value of microcirculation inflammation (MI; defined by the addition of glomerulitis (g) and peritubular capillaritis (ptc) scores) to assess long-term graft survival in a retrospective cohort study. Out of all transplant patients with standard immunological risk (n = 638), 79 (12.4%) developed dnDSA and 58/79 (73%) had an indication biopsy at or after dnDSA development. Based on the MI score on that indication biopsy patients were categorized, MI0 (n = 26), MI1 + 2 (n = 21) and MI ≥ 3 (n = 11). The MI groups did not differ significantly pretransplantation, whereas posttransplantation higher MI scores developed more anti-HLA class I + II DSA (p = 0.011), showed more TCMR (p < 0.001) and showed a trend to C4d-positive staining (p = 0.059). Four-year graft survival estimates from time of indication biopsy were MI0 96.1%, MI1 + 2 76.1% and MI ≥ 3 17.1%; resulting in a 24-fold increased risk of graft failure in the MI ≥ 3 compared to the MI0 group (p = 0.003; 95% CI [3.0-196.0]). When adjusted for C4d, MI ≥ 3 still had a 21-fold increased risk of graft failure (p = 0.005; 95% CI [2.5-180.0]), while C4d positivity on indication biopsy lost significance. In renal transplant patients with de novo DSA, microcirculation inflammation, defined by g + ptc, associates with graft survival.


Assuntos
Anticorpos/imunologia , Transplante de Rim/imunologia , Transplante de Rim/métodos , Rim/imunologia , Insuficiência Renal/terapia , Adulto , Biópsia , Complemento C4b/análise , Feminino , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Inflamação , Masculino , Microcirculação , Pessoa de Meia-Idade , Modelos Estatísticos , Fragmentos de Peptídeos/análise , Estudos Retrospectivos , Fatores de Risco , Doadores de Tecidos
4.
Am J Transplant ; 11(3): 470-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21299828

RESUMO

It has been shown that low-level preformed donor-specific antibodies (DSAbs) detected by luminex beads in the setting of a negative CDC and flow cytometry crossmatch (CDC/FCXM) are associated with inferior allograft outcomes. The relevance of preformed DSAbs in patients receiving alemtuzumab induction and tacrolimus monotherapy has not been studied. Four hundred and eighty renal transplant recipients with a negative CDC/FCXM had their pretransplant sera retrospectively screened for DSAbs. 45/480 (9.4%) of patients were found to have preformed DSAbs. Females and patients receiving regrafts were more likely to have a DSAb (p = 0.008 and p < 0.0001, respectively). Patients with DSAbs had inferior allograft survival (p = 0.047), increased incidence of antibody-mediated rejection (p < 0.0001) and inferior allograft function at 6 months posttransplant (p = 0.017). Patients with HLA class I DSAb (alone or in combination with a Class II DSAb) with high mean fluorescence intensities (MFIs) were at highest risk. We conclude that patients with preformed DSAb are at high risk of adverse outcomes when receiving a minimal immunosuppressive regime incorporating alemtuzumab induction. Patients found to have a preformed DSAb despite a negative crossmatch might benefit from augmented immunosuppression.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Antineoplásicos/uso terapêutico , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Isoanticorpos/sangue , Transplante de Rim/imunologia , Tacrolimo/uso terapêutico , Doadores de Tecidos , Alemtuzumab , Anticorpos Monoclonais Humanizados , Feminino , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Imunossupressores/uso terapêutico , Transplante de Rim/efeitos adversos , Transplante de Rim/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Transplante Homólogo/imunologia , Resultado do Tratamento
5.
Ecotoxicol Environ Saf ; 73(6): 1255-63, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20688396

RESUMO

The effects of sewage sludge selectively enriched with Cd and Zn, both singly and in combination, on the bacterial, fungal, Alphaproteobacteria and Actinobacteria communities of a soil under arable or grassland management were studied with a PCR-DGGE approach. The effects of Cd and Zn were evaluated after a short time (7 d) when the Cd and Zn solubility were low and the C availability was high, and again after 180 d when the labile sludge C was mineralized and the effects of heavy metals predominated. In the arable soil all treatments induced significant short-term changes in the studied microbial groups, and long-term changes were observed in Actinobacteria and fungal communities. In the grassland soil, all treatments induced significant short-term changes in the studied microbial groups except for Alphaproteobacteria and fungi, and long-term effects on the actinobacteria and fungal communities. It was concluded that incorporation of Cd- and Zn-rich sludge into soils may have both short- and long-term effects on various bacterial phylogenetic groups whereas the metals may be better tolerated by the dominant soil fungi. In this study the impact was greater in arable than in grassland soil.


Assuntos
Actinobacteria/efeitos dos fármacos , Alphaproteobacteria/efeitos dos fármacos , Cádmio/toxicidade , Fungos/efeitos dos fármacos , Esgotos , Microbiologia do Solo , Zinco/toxicidade , Actinobacteria/isolamento & purificação , Alphaproteobacteria/isolamento & purificação , Cádmio/análise , Eletroforese em Gel de Gradiente Desnaturante , Fungos/isolamento & purificação , Reação em Cadeia da Polimerase , RNA Bacteriano/genética , RNA Fúngico/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Esgotos/química , Esgotos/microbiologia , Microbiologia do Solo/normas , Zinco/análise
6.
Artigo em Inglês | MEDLINE | ID: mdl-31357172

RESUMO

Rainbow smelt, Osmerus mordax, have an impressive ability to acclimate to very cold water. Rainbow smelt exposed to cold (<5 °C) for an extended period of time have faster sustained swimming speeds and increased contraction kinetics in their myotomal muscle compared to warm acclimated fish. We used RNA Sequencing reactions (RNA-Seq) to explore how gene expression underlies thermal acclimation by muscle in these fish. Transcriptome analysis is limited in species that lack an annotated genome, such as rainbow smelt. The Trinity software package permits the de novo assembly of a rainbow smelt transcriptome with a modest learning curve. The transcriptome was then analyzed with Kallisto to quantify the abundance of each transcript represented in the full transcriptome and Sleuth to analyze the resulting RNA-seq datasets. Subsequently qPCR was used to explore patterns of thermal acclimation and gene expression for genes of metabolic and muscle contractile function. These methodologies revealed shifts in both muscle and metabolic gene expression that contribute to the thermal acclimation response in rainbow smelt. In fast-twitch, anaerobic white muscle, slow isoforms of myosin heavy and light chain tended to be down-regulated with exposure to cold in myotomal muscle, while fast isoforms were unchanged. Genes associated with protein turnover and aerobic metabolism were up-regulated in the white muscle, while those associated with anaerobic metabolism and the cell cycle were down-regulated. Collectively the results suggest that thermal acclimation to cold is complex process of apparent shifts in gene expression.


Assuntos
Aclimatação , Temperatura Baixa , Peixes/genética , Peixes/fisiologia , Expressão Gênica , Transcriptoma , Animais , Análise de Sequência de RNA
7.
Waste Manag ; 28(4): 723-33, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18042372

RESUMO

Biological and chemical stabilization of organic C was assessed in soils sampled from the long-term experiments at Rothamsted (UK), representing a wide range of carbon inputs and managements by extracting labile, non-humified organic matter (NH) and humic substances (HS). Four sequentially extracted humic substances fractions of soil organic matter (SOM) were extracted and characterized before and after a 215-day laboratory incubation at 25 degrees C from two arable soils, a woodland soil and an occasionally stubbed soil. The fractions corresponded to biochemically stabilised SOM extracted in 0.5M NaOH (free fulvic acids (FA) and humic acids (HA)) and chemically plus biochemically stabilised SOM extracted from the residue with 0.1M Na4P2O7 plus 0.1M NaOH (bound FA and HA). Our aim was to investigate the effects of chemical and biochemical stabilization on carbon sequestration. The non-humic to humic (NH/H) C ratio separated the soils into two distinct groups: arable soils (unless fertilised with farmyard manure) had an NH/H C ratio between 1.05 and 0.71, about twice that of the other soils (0.51-0.26). During incubation a slow, but detectable, decrease in the NH/H C ratio occurred in soils of C input equivalent or lower to 4Mgha(-1)y(-1), whereas the ratio remained practically constant in the other soils. Before incubation the free to bound humic C ratio increased linearly (R2=0.91) with C inputs in the soils from the Broadbalk experiment and decreased during incubation, showing that biochemical stabilization is less effective than chemical stabilization in preserving humic C. Changes in delta13C and delta15N after incubation were confined to the free FA fractions. The delta13C of free FA increased by 1.48 and 0.80 per thousand, respectively, in the stubbed and woodland soils, indicating a progressive biological transformation. On the contrary, a decrease was observed for the bound FA of both soils. Concomitantly, a Deltadelta15N of up to +3.52 per thousand was measured after incubation in the free FA fraction and a -2.58 Deltadelta15N in the bound FA. These changes, which occurred during soil incubation in the absence of C inputs, indicate that free FA fractions were utilised by soil microorganisms, and bound FA were decomposed and replaced, in part, by newly synthesized FA. The 13CPMAS-TOSS NMR spectra of free HA extracted before and after 215 days of incubation were mostly unchanged. In contrast, changes were evident in bound HA and showed an increase in aromatic C after incubation.


Assuntos
Benzopiranos/análise , Carbono/análise , Substâncias Húmicas/análise , Solo/análise , Reino Unido
8.
Waste Manag ; 28(4): 716-22, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18383584

RESUMO

Soil organic matter comprises all dead plant and animal residues, from the most recent inputs to the most intensively humified. We have found that traces of fresh substrates at microg g(-1) soil concentrations (termed 'trigger molecules') activate the biomass to expend more energy than is contained in the original 'trigger molecules'. In contrast, we suggest that the rate limiting step in soil organic matter mineralisation is independent of microbial activity, but is governed by abiological processes (which we term the Regulatory Gate theory). These two findings have important implications for our understanding of carbon mineralisation in soil, a fundamental process in the sequestration of soil organic matter.


Assuntos
Carbono/metabolismo , Microbiologia do Solo , Trifosfato de Adenosina/metabolismo , Aminoácidos/metabolismo , Biomassa , Dióxido de Carbono/metabolismo , Ácidos Graxos/metabolismo , Glucose/metabolismo , Ácido Glutâmico/metabolismo , Extratos Vegetais/metabolismo , Hidrolisados de Proteína/metabolismo , Solo
9.
Cancer Res ; 35(1): 54-7, 1975 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1167347

RESUMO

DNA isolated from mouse embryo cell cultures that had been treated with [3H]benzo(alpha)pyrene was degraded with enzymes to deoxyribonucleosides, and the hydrocarbon-deoxyribonucleoside products were isolated by chromatography on a Sephadex LH20 column eluted with a water: methanol gradient. The hydrocarbon-deoxyribonucleoside products were not identical to those found in similar chromatograms of enzyme digests of DNA that had been reacted with benzo(alpha)pyrene-4,5-oxide in aqueous ethanol solution. This finding suggests that the metabolic activation of benzo(alpha)pyrene that results in this hydrocarbon becoming covalently bound to DNA in mouse embryo cells in culture may be more complex than simply formation of a K-region epoxide and reaction of that compound with the cellular DNA.


Assuntos
Benzopirenos/metabolismo , Células Cultivadas/metabolismo , DNA/metabolismo , Compostos de Epóxi/metabolismo , Éteres Cíclicos/metabolismo , Animais , Cromatografia , Desoxirribonucleosídeos/isolamento & purificação , Embrião de Mamíferos , Etanol , Metanol , Camundongos , Trítio
10.
Cancer Res ; 35(5): 1263-9, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-1120312

RESUMO

Rat liver microsomes (induced by 3-methylcholanthrene) were used to catalyze the binding of tritium-labeled benzo(alpha)pyrene to DNA. Enzymic degradation of this DNA to deoxyribonucleosides, followed by separation of the products by Sephadex LH20 column chromatography, revealed two major products. One of these was shown to be the same as that obtained from DNA with benzo(alpha)pyrene bound following treatment of mouse embryo cells in culture with the carcinogen. Neither product resembled those obtained from DNA that had been caused to react with benzo(alpha)pyrene 4,5-oxide (K-region eposide). The aryl hydrocarbon hydroxylase activity of the microsome preparations was determined and related to the extent of microsome-catalyzed hydrocarbon binding. Inhibitors of the enzyme epoxide hydrase increased this binding but caused the loss of one of the two major products. On the basis of the results obtained, a model is proposed of the mechanism of benzo(alpha)pyrene metabolism and DNA binding.


Assuntos
Benzopirenos/isolamento & purificação , DNA/metabolismo , Desoxirribonucleosídeos/isolamento & purificação , Microssomos Hepáticos/metabolismo , Hidrocarboneto de Aril Hidroxilases/metabolismo , Benzopirenos/metabolismo , Desoxirribonucleosídeos/metabolismo , Compostos de Epóxi , Hidroliases/antagonistas & inibidores , Microssomos Hepáticos/enzimologia , Ligação Proteica
11.
Cancer Res ; 36(7 PT 1): 2306-11, 1976 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1277134

RESUMO

RNA was isolated by a phenol extraction method from mouse embryo cells treated in culture with either [G-3H]-7-methylbenz(a)anthracene or [G-3H]-7-methylbenz(a)anthracene 5,6-oxide (the K-region epoxide). The RNA was degraded to ribonucleosides, mixed with ultraviolet-absorbing quantities of the epoxide ribonucleoside products isolated from RNA that had reacted with 7-methylbenz(a)anthracene 5,6-oxide in aqueous ethanol solution, and chromatographed on a column of Sephadex LH-20 eluted with a methanol:water gradient. The 7-methyl-benz(a)anthracene 5,6-oxide ribonucleoside products formed in cells were identical to those formed in aqueous solution, although the relative amounts of the products varied. The majority of these epoxide-ribonucleoside products were not identical to the products formed in cells treated with the parent hydrocarbon. These results suggest that the major reactive form of 7-methylbenz(a)anthracene that binds to RNA in mouse embryo cells is not the K-region epoxide of this hydrocarbon.


Assuntos
Benzo(a)Antracenos , RNA , Benzo(a)Antracenos/metabolismo , Sítios de Ligação , Células Cultivadas , Fenômenos Químicos , Química , Cromatografia em Gel , Compostos de Epóxi/metabolismo , RNA/isolamento & purificação , RNA/metabolismo
12.
Oncogene ; 1(2): 229-33, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3325883

RESUMO

The primary structure of the protein tyrosine kinase domain of the human met gene has been determined from cDNA clones prepared from transcripts of the activated human met gene. These analyses reveal that the met kinase domain (located on human chromosome 7) possesses unique features that distinguish met from other members of the src family of protein tyrosine kinases. The results also demonstrate that the product of the activated met gene is a fusion protein and that the amino terminal end of this fusion protein, which is encoded by human chromosome 1, exhibits homology to laminin B1.


Assuntos
Proteínas Tirosina Quinases , Proteínas Proto-Oncogênicas , Sequência de Aminoácidos , Sequência de Bases , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 7 , Clonagem Molecular , DNA/genética , Humanos , Laminina/genética , Dados de Sequência Molecular , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética
13.
Oncogene ; 2(6): 593-9, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2838789

RESUMO

The DNA sequence of cDNA clones prepared from transcripts of the mouse met proto-oncogene reveals that the mouse met gene encodes a 1380 amino acid protein with the characteristics of a growth factor receptor. This protein can be divided into several putative domains, including an intracellular protein tyrosine kinase domain, a transmembrane domain and a 929 amino acid extracellular domain, possessing a potential proteolytic cleavage site with the sequence Lys-Arg-Arg-Lys-Arg-Ser. To gain additional insights into the function of the met protein we have examined the level of met transcripts in tissues of the late-gestation mouse conceptus. Transcription of met was observed in most of the tissues analysed, but the highest levels of met mRNA were detected in the yolk sac, amnion and kidney; no transcripts were detectable in the calvaria. Chromosomal localization using a series of mouse-hamster hybrid cell lines has demonstrated that met is located on mouse chromosome 6.


Assuntos
Camundongos/genética , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes , Receptores de Superfície Celular/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , Substâncias de Crescimento , Dados de Sequência Molecular
14.
Biochim Biophys Acta ; 1330(2): 157-64, 1997 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-9408168

RESUMO

The proton permeability of the mitochondrial inner membrane has been shown to correlate with the fatty acid composition of its phospholipids. In this paper, we test the hypothesis that the proton permeability of the phospholipid bilayer portion of the membrane depends on phospholipid fatty acid composition. We measured the proton permeability of liposomes made from the mitochondrial inner membrane phospholipids of eight vertebrates, representing a ten-fold range of mitochondrial proton leak and a three fold range of unsaturation index. At a membrane potential (delta psi) of 160 mV at 37 degrees C, the liposomes all had the same proton leak rate, about 30 nmol protons min-1 mg-1 phospholipid. There was no correlation between liposome proton permeability and phospholipid fatty acid composition.


Assuntos
Ácidos Graxos/metabolismo , Membranas Intracelulares/metabolismo , Lipossomos/metabolismo , Lipídeos de Membrana/metabolismo , Mitocôndrias Hepáticas/metabolismo , Fosfolipídeos/metabolismo , Prótons , Animais , Técnicas In Vitro , Membranas Intracelulares/química , Potenciais da Membrana , Mitocôndrias Hepáticas/química , Permeabilidade , Especificidade da Espécie , Vertebrados
15.
Biochim Biophys Acta ; 1410(2): 215-28, 1999 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-10076028

RESUMO

Damage to the mitochondrial electron transport chain has been suggested to be an important factor in the pathogenesis of a range of neurological disorders, such as Parkinson's disease, Alzheimer's disease, multiple sclerosis, stroke and amyotrophic lateral sclerosis. There is also a growing body of evidence to implicate excessive or inappropriate generation of nitric oxide (NO) in these disorders. It is now well documented that NO and its toxic metabolite, peroxynitrite (ONOO-), can inhibit components of the mitochondrial respiratory chain leading, if damage is severe enough, to a cellular energy deficiency state. Within the brain, the susceptibility of different brain cell types to NO and ONOO- exposure may be dependent on factors such as the intracellular reduced glutathione (GSH) concentration and an ability to increase glycolytic flux in the face of mitochondrial damage. Thus neurones, in contrast to astrocytes, appear particularly vulnerable to the action of these molecules. Following cytokine exposure, astrocytes can increase NO generation, due to de novo synthesis of the inducible form of nitric oxide synthase (NOS). Whilst the NO/ONOO- so formed may not affect astrocyte survival, these molecules may diffuse out to cause mitochondrial damage, and possibly cell death, to other cells, such as neurones, in close proximity. Evidence is now available to support this scenario for neurological disorders, such as multiple sclerosis. In other conditions, such as ischaemia, increased availability of glutamate may lead to an activation of a calcium-dependent nitric oxide synthase associated with neurones. Such increased/inappropriate NO formation may contribute to energy depletion and neuronal cell death. The evidence available for NO/ONOO--mediated mitochondrial damage in various neurological disorders is considered and potential therapeutic strategies are proposed.


Assuntos
Mitocôndrias/metabolismo , Doenças do Sistema Nervoso/etiologia , Óxido Nítrico/metabolismo , Esclerose Lateral Amiotrófica/etiologia , Astrócitos/metabolismo , Astrócitos/patologia , Morte Celular , Transporte de Elétrons/genética , Ácido Glutâmico/metabolismo , Humanos , Mitocôndrias/patologia , Doenças do Sistema Nervoso/genética , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/genética , Neurônios/metabolismo , Neurônios/patologia , Nitratos/metabolismo , Permeabilidade
16.
Breast ; 14(1): 65-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15695084

RESUMO

Squamous cell carcinoma in situ (Bowen's disease) is a common skin condition but has only rarely been described on the nipple. All reported cases have been treated with wide local excision and observation. A new treatment for Bowen's disease is photodynamic therapy. This has been reported as being able to treat Bowen's disease in other sites effectively with an acceptable local recurrence rate. We describe two patients presenting with itching and scaling of the nipple which were histologically proven Bowen's disease, one of these patients was treated successfully with a combination of photodynamic therapy and cryotherapy: this is the first time such a lesion has been treated in this way.


Assuntos
Doença de Bowen/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Crioterapia , Fotoquimioterapia , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Terapia Combinada , Feminino , Humanos , Mamilos/patologia
17.
Exp Hematol ; 18(5): 421-5, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2338131

RESUMO

We treated 17 patients with chronic myeloid leukemia (CML) by bone marrow transplantation using marrow from human leukocyte antigen (HLA)-matched unrelated donors. Patients were conditioned with a combination of in vivo monoclonal antibodies, chemotherapy with daunorubicin (n = 7) or busulfan (n = 10) and cyclophosphamide, and both total body and total lymphoid irradiation. Donor marrow was depleted of T cells by incubation with monoclonal antibodies of the Campath series. Fourteen (88%) of 16 evaluable patients had sustained engraftment. Four (27%) of the 15 evaluable patients developed acute graft-versus-host disease (GVHD) of grade II or greater, and 4 of 12 evaluable patients developed chronic GVHD. Three patients developed hematological and two developed cytogenetic evidence of relapse. Eight patients (47%) survive at a median follow-up of 32 months (range 10-51 months), giving an actuarial survival of 44%. Five patients remain alive without evidence of hematological or cytogenetic relapse, giving an actuarial disease-free survival of 27%. Pneumonitis caused or contributed to death in six of the nine patients who died. We conclude that T-cell depletion can prevent the severest forms of GVHD but also increases the risk of relapse after transplant with unrelated donors, as it does with HLA-identical siblings. Nevertheless the use of matched unrelated donors should be considered for CML patients who lack HLA-identical siblings.


Assuntos
Transplante de Medula Óssea , Histocompatibilidade , Leucemia Mielogênica Crônica BCR-ABL Positiva/cirurgia , Adolescente , Adulto , Feminino , Doença Enxerto-Hospedeiro , Antígenos HLA/análise , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia
18.
FEBS Lett ; 446(2-3): 261-3, 1999 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-10100854

RESUMO

The assumption that reversible inhibition of mitochondrial respiration by nitric oxide (NO.) represents inhibition of ATP synthesis is unproven. NO. could theoretically inhibit the oxygen consumption with continued ATP synthesis, by acting as an electron acceptor from cytochrome c or as a terminal electron acceptor in stead of oxygen. We report here that NO. does reversibly inhibit brain mitochondrial ATP synthesis with a time course similar to its inhibition of respiration. Whilst such inhibition was largely reversible, there appeared to be a small irreversible component which may theoretically be due to peroxynitrite formation, i.e. as a result of the reaction between NO. and superoxide, generated by the mitochondrial respiratory chain.


Assuntos
Trifosfato de Adenosina/biossíntese , Óxido Nítrico/metabolismo , Trifosfato de Adenosina/antagonistas & inibidores , Animais , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Óxido Nítrico/farmacologia , Ratos , Ratos Wistar
19.
FEBS Lett ; 416(1): 90-2, 1997 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-9369240

RESUMO

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key glycolytic enzyme regulated by many diverse mechanisms. In this study we present evidence that GAPDH activity is stimulated in the presence of oxyhemoglobin (2.3-fold, P < 0.005). No stimulation was seen by myoglobin, and only slight stimulation (1.2-fold, not significant) by methemoglobin was observed. Such stimulation may have physiological significance as 1,3-bis-phosphoglycerate, the product of GAPDH, isomerises to 2,3-bis-phosphoglycerate, an allosteric effector that decreases the oxygen affinity of hemoglobin, thus providing a feedback loop. The results suggest that when assaying GAPDH activity in biological samples, hemoglobin content should be taken into account.


Assuntos
Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Oxiemoglobinas/farmacologia , Animais , Ativação Enzimática , Fígado/enzimologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA
20.
Antioxid Redox Signal ; 3(2): 215-29, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11396477

RESUMO

Many of the biological and pathological effects of nitric oxide (NO) are mediated through cell signaling pathways that are initiated by NO reacting with metalloproteins. More recently, it has been recognized that the reaction of NO with free radicals such as superoxide and the lipid peroxyl radical also has the potential to modulate redox signaling. Although it is clear that NO can exert both cytotoxic and cytoprotective actions, the focus of this overview are those reactions that could lead to protection of the cell against oxidative stress in the vasculature. This will include the induction of antioxidant defenses such as glutathione, activation of mitogen-activated protein kinases in response to blood flow, and modulation of mitochondrial function and its impact on apoptosis. Models are presented that show the increased synthesis of glutathione in response to shear stress and inhibition of cytochrome c release from mitochondria. It appears that in the vasculature NO-dependent signaling pathways are of three types: (i) those involving NO itself, leading to modulation of mitochondrial respiration and soluble guanylate cyclase; (ii) those that involve S-nitrosation, including inhibition of caspases; and (iii) autocrine signaling that involves the intracellular formation of peroxynitrite and the activation of the mitogen-activated protein kinases. Taken together, NO plays a major role in the modulation of redox cell signaling through a number of distinct pathways in a cellular setting.


Assuntos
Mitocôndrias/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Nitratos/fisiologia , Óxido Nítrico/fisiologia , Transdução de Sinais/fisiologia , Animais , Oxirredução
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