RESUMO
BACKGROUND: Checkpoint inhibitors are now frequently used for oncologic conditions. The impact of these therapies in solid organ transplant recipients was not assessed in clinical trials. Subsequent case reports highlight the major detrimental interactions of checkpoint inhibitors and the high risk of allograft rejection with their use. Patient outcomes have not been assessed in long-term follow-up. METHODS: We conducted a retrospective review of kidney transplant recipients with metastatic cancer who received checkpoint inhibitors at a single center between April 2015 and May 2018. RESULTS: Six kidney transplant recipients with metastatic cancers that were not responding to first-line treatments met study criteria. These include 2 with squamous cell cancers, 2 with melanoma, 1 with renal cell cancer, and 1 with adenocarcinoma of the lung. Four patients received anti-programmed cell death protein-1 (PD-1) antibody and 2 received a combination of anticytotoxic T-lymphocyte-associated protein 4 and anti-PD-1 antibodies. Three out of 6 patients developed acute kidney injury. Two were biopsy-proven acute rejections with subsequent graft failures. The third was attributed to rejection, but improved after discontinuing the checkpoint inhibitor. Five out of 6 patients had cancer progression and only 1 patient had remission. CONCLUSIONS: Providers and patients need to be aware of the high risk of rejection and the poor remission rate with the use of checkpoint inhibitors in kidney transplant patients. More research is warranted to assess the optimal maintenance immunosuppression during the use of checkpoint inhibitor therapy that would not diminish the chances of remission.
Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Rejeição de Enxerto/tratamento farmacológico , Terapia de Imunossupressão/métodos , Ipilimumab/uso terapêutico , Transplante de Rim/métodos , Nivolumabe/uso terapêutico , Transplantados , Doença Aguda , Idoso , Antineoplásicos Imunológicos/uso terapêutico , Biópsia , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/patologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologiaRESUMO
Palladium-based nanoparticles immobilized in polymeric matrices were applied to the reductive dechlorination of 3,3',4,4'-tetrachlorobiphenyl (PCB77) at room temperature. Two different dechlorination platforms were evaluated using (1) Pd nanoparticles within conductive polypyrrole films; or (2) immobilized Fe/Pd nanoparticles within polyvinylidene fluoride microfiltration membranes. For the first approach, the polypyrrole film was electrochemically formed in the presence of perchlorate ions that were incorporated into the film to counter-balance the positive charges of the polypyrrole chain. The film was then incubated in a solution containing tetrachloropalladate ions, which were exchanged with the perchlorate ions within the film. During this exchange, reduction of tetrachloropalladate by polypyrrole occurred, which led to the formation of palladium nanoparticles within the film. For the second approach, the membrane-supported Fe/Pd nanoparticles were prepared in three steps: polymerization of acrylic acid in polyvinylidene fluoride microfiltration membrane pores was followed by ion exchange of Fe(2+), and then chemical reduction of the ferrous ions bound to the carboxylate groups. The membrane-supported iron nanoparticles were then soaked in a solution of tetrachloropalladate resulting in the deposition of Pd on the Fe surface. The nanoparticles prepared by both approaches were employed in the dechlorination of PCB77. The presence of hydrogen was required when the monometallic Pd nanoparticles were employed. The results indicate the removal of chlorine atoms from PCB77, which led to the formation of lower chlorinated intermediates and ultimately biphenyl. Toxicity associated with vascular dysfunction by PCB77 and biphenyl was compared using cultured endothelial cells. The data strongly suggest that the dechlorination system used in this study markedly reduced the proinflammatory activity of PCB77, a persistent organic pollutant.
Assuntos
Células Endoteliais/efeitos dos fármacos , Poluentes Ambientais/química , Poluentes Ambientais/toxicidade , Ferro/química , Miócitos de Músculo Liso/efeitos dos fármacos , Paládio/química , Bifenilos Policlorados/química , Bifenilos Policlorados/toxicidade , Animais , Ciclo-Oxigenase 2/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Eletroquímica , Cromatografia Gasosa-Espectrometria de Massas , Indicadores e Reagentes , Microscopia Eletrônica de Transmissão , Nanopartículas , Oxirredução , Tamanho da Partícula , Suínos , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
Poly(amino acids) are natural chelating agents for various metal ions. Zinc ions were encapsulated in situ in a conductive polypyrrole film using polyglutamic acid as a localized complexing agent within the film. The subsequent electrochemical reduction of the metal ions to zero-valent metal leads to the formation of the nanoparticles. The electrochemical approach demonstrated in this report provides facile regeneration of the particles and also prevents aggregation of nanoparticles in the conductive polymeric film. The correlation of the amount of zinc with the thickness of the film indicates that the zinc resides largely in the outer layer of the film. TEM and EDS data show that the nanoparticles formed are composed of zinc and are 18 +/- 7 nm in diameter. The nanoparticle/ polymer composite was used to reduce halogenated organics, indicating its potential usefulness in remediation applications.
Assuntos
Aminoácidos/química , Eletroquímica/métodos , Metais/química , Nanopartículas/química , Nanotecnologia/métodos , Quelantes/farmacologia , Cloro/química , Concentração de Íons de Hidrogênio , Íons , Microscopia Eletrônica de Transmissão , Modelos Químicos , Ácido Poliglutâmico/química , Polímeros/química , Pirróis/química , Zinco/químicaRESUMO
Colon cancer is the third most malignant neoplasm in the world and it remains today an important cause of death, especially in western countries. In this study, we have evaluated the chemopreventive efficacy of morin on tissue lipid peroxidation and antioxidant status, which are used as biomarkers in 1,2-dimethylhydrazine-induced colon carcinogenesis in a rat model. Male Wistar rats were divided into four groups and received high fat diet. Group 1 served as control, groups 2 and 4 were given a daily treatment of morin (50 mg/kg body weight) orally, everyday for a total period of 30 weeks. Groups 3 and 4 were given weekly subcutaneous injections of DMH at a dose of 20 mg/kg body weight in the groin for 15 weeks. Animals were sacrificed at the end of 30 weeks. The liver, intestine, colon and caecum from different groups were subjected to histopathological studies, determination of lipid peroxidation and antioxidant status. Our results showed decreased levels of liver enzymic and non-enzymic antioxidants and increased levels of lipid peroxidation (LPO) products such as tissue thiobarbituricacid substances (TBARS), lipid hydroperoxides (LOOH) and conjugated dienes (CD) in DMH treated rats, which were significantly (P < 0.05) reversed on morin supplementation. Moreover, intestinal, colonic and caecal TBARS, LOOH, CD and also the antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) and reduced glutathione (GSH) were significantly diminished in DMH treated rats, which were significantly (P < 0.05) elevated on simultaneous morin supplementation. Moreover, enhanced activity of intestinal, colonic and caecal ascorbic acid and alpha-tocopherol levels were also observed in DMH alone treated rats, which were significantly (P < 0.05) reduced on morin supplementation. These results indicate that morin could exert a significant chemopreventive effect on colon carcinogenesis induced by DMH.