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1.
Am J Gastroenterol ; 108(7): 1168-73, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23545711

RESUMO

OBJECTIVES: Controversy exists regarding whether to place a plastic or a metal endobiliary stent in patients with resectable pancreatic cancer who require biliary drainage. Although self-expandable metal stents (SEMS) provide better drainage compared with plastic stents, concerns remain that SEMS may compromise resection and increase postoperative complications. Our objective was to compare surgical outcomes of patients undergoing pancreaticoduodenectomy (PD) with SEMS in place vs. plastic endoscopic stents (PES) and no stents (NS). METHODS: We performed a retrospective analysis from a prospective database of all patients undergoing either attempted or successful PD with SEMS, PES, or NS in place at the time of operation. Patients were compared with regard to perioperative complications, margin status, and the rate of intraoperative determination of unresectability. RESULTS: A total of 593 patients underwent attempted PD. Of these, 84 patients were locally unresectable intraoperatively and 509 underwent successful PD, of which 71 had SEMS, 149 had PES, and 289 had NS. Among patients who had a preoperative stent, SEMS did not increase overall or serious postoperative complications, 30-day mortality, length of stay, biliary anastomotic leak, or positive margin, but was associated with more wound infections and longer operative times. In those with adenocarcinoma, intraoperative determination of local unresectability was similar in the SEMS group compared with other groups, with 16 (19.3%) in SEMS compared with 29 (17.7%) in PES (P=0.862), and 31 (17.5%) in NS (P=0.732). CONCLUSIONS: Placement of SEMS is not contraindicated in patients with resectable pancreatic cancer who require preoperative biliary drainage.


Assuntos
Adenocarcinoma/cirurgia , Colestase/terapia , Drenagem/instrumentação , Metais/efeitos adversos , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Stents/efeitos adversos , Adenocarcinoma/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Anastomótica/etiologia , Colestase/etiologia , Drenagem/efeitos adversos , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Neoplasias Pancreáticas/complicações , Plásticos/efeitos adversos , Período Pré-Operatório , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
2.
Nat Nanotechnol ; 11(11): 977-985, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27668796

RESUMO

The design of cancer-targeting particles with precisely tuned physicochemical properties may enhance the delivery of therapeutics and access to pharmacological targets. However, a molecular-level understanding of the interactions driving the fate of nanomedicine in biological systems remains elusive. Here, we show that ultrasmall (<10 nm in diameter) poly(ethylene glycol)-coated silica nanoparticles, functionalized with melanoma-targeting peptides, can induce a form of programmed cell death known as ferroptosis in starved cancer cells and cancer-bearing mice. Tumour xenografts in mice intravenously injected with nanoparticles using a high-dose multiple injection scheme exhibit reduced growth or regression, in a manner that is reversed by the pharmacological inhibitor of ferroptosis, liproxstatin-1. These data demonstrate that ferroptosis can be targeted by ultrasmall silica nanoparticles and may have therapeutic potential.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Ferro/metabolismo , Nanopartículas/química , Aminoácidos/deficiência , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Lisossomos/efeitos dos fármacos , Melanoma , Camundongos , Camundongos SCID , Nanopartículas/uso terapêutico , Tamanho da Partícula , Polietilenoglicóis/química , Quinoxalinas/farmacologia , Dióxido de Silício/química , Compostos de Espiro/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , alfa-MSH/química
3.
J Control Release ; 149(3): 292-8, 2011 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21047536

RESUMO

Positron emission tomography (PET) of epidermal growth factor receptor (EGFR) kinase-specific radiolabeled tracers could provide a means for non-invasively characterizing EGFR expression and signaling activity in patients' tumors before, during, and after therapy with EGFR inhibitors. Towards this goal, our group has developed PET tracers which irreversibly bind to EGFR. However, tumor uptake is relatively low because of both the lipophilicity of such tracers (e.g. the morpholino-[124I]-IPQA [SKI 212243]), with octanol-to-water partition coefficients of up to 4, and a short dwell time in the blood and significant hepatobiliary clearance and intestinal reuptake. Liposomal nanoparticle delivery systems may favorably alter the pharmacokinetic profile and improve tumor targeting of highly lipophilic but otherwise promising cancer imaging tracers, such as the EGFR inhibitor SKI 243. SKI 243 is therefore an interesting model molecule for incorporation into lipid-based nanoparticles, as it would not only improve their solubility but also increase the circulation time, availability and, potentially, targeting of tumors. In the current study, we compared the pharmacokinetics and tumor targeting of the bare EGFR kinase-targeting radiotracer SKI 212243 (SKI 243) with that of the same tracer embedded in liposomes. SKI 243 and liposomal SKI 243 are both taken up by tumor xenografts but liposomal SKI 243 remained in the blood longer and consequently exhibited a 3- to 6-fold increase in uptake in the tumor among several other organs.


Assuntos
Antineoplásicos/administração & dosagem , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Humanos , Lipossomos , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Compostos Radiofarmacêuticos/farmacocinética
4.
J Nucl Med ; 50(10): 1605-10, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19759114

RESUMO

UNLABELLED: Salivary gland side effects (SSEs) can be a source of significant morbidity in thyroid cancer patients receiving radioactive iodine (RAI) for remnant ablation or therapy. However, the incidence, time course, and ultimate resolution of SSEs that develop in the first few months after a single administered activity of RAI for remnant ablation has not be adequately defined. METHODS: We retrospectively reviewed the clinical records of patients after RAI remnant ablation (RRA) to determine the incidence of salivary gland-related side effects reported within the first year of RRA, the dose-response relationship between administered activity and specific SSEs, and the incidence of specific SSEs based on the method of preparation for remnant ablation (recombinant human thyroid-stimulating hormone [rhTSH] vs. traditional thyroid hormone withdrawal [THW]). RESULTS: SSEs were reported within the first year of RAI ablation in 39% of a cohort of 262 patients (66% women, 93% papillary thyroid cancer; median dose, 5,217 MBq [141 mCi]). Persistent side effects were noted after a median of 7 y in 5% or less of the entire cohort. However, when side effects developed in patients during the first year, the incidence of persistence of the symptom at last follow-up ranged from 5% to 13%. A statistically significant dose response was seen between administered activity of RAI and development of salivary gland swelling (P = 0.001, logistic dose-response curve) but not with dry mouth (P = 0.63), altered taste (P = 0.27), or salivary gland pain (P = 0.152). SSEs developed in 14% of patients receiving administered activities of 1,110 MBq (30 mCi); administered activities of 2,775 MBq (75 mCi) or more were associated with symptoms in 40% of patients (P = 0.046). Despite receiving a statistically higher administered activity (5,661 +/- 2,997 MBq [153 +/- 81 mCi] for THW vs. 4,958 +/- 2,294 MBq [134 +/- 62 mCi] for rhTSH), THW was associated with a lower rate of salivary gland swelling than the rhTSH preparation (20% vs. 10%; P = 0.017), without differences in the development of dry mouth, altered taste, or salivary gland pain. CONCLUSION: Although SSEs occurred in 39% of patients after routine RRA, they were usually transient, so that the overall incidence of persistent side effects at a median follow-up of 7 y was only 5%. Even though the risk for persistent side effects is rather small, these data do emphasize the need to select patients carefully for RRA who are thought to be at moderate to high risk for recurrence and to use the minimally effective dose of RAI activity, in an attempt to maximize the potential benefit while minimizing the risk for adverse events for an individual patient.


Assuntos
Técnicas de Ablação/efeitos adversos , Complicações Pós-Operatórias/etiologia , Glândulas Salivares/efeitos da radiação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Glândulas Salivares/patologia , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/terapia , Tireotropina/uso terapêutico , Fatores de Tempo , Adulto Jovem
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