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1.
J Surg Oncol ; 124(8): 1390-1401, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34499741

RESUMO

BACKGROUND AND OBJECTIVES: Pancreatic neuroendocrine tumors (PNETs) represent a rare form of pancreatic cancer. Racial/ethnic disparities have been documented in pancreatic ductal adenocarcinoma, but health disparities have not been well described in patients with PNETs. METHODS: A retrospective review of patients with PNETs in the National Cancer Database was performed for 2004-2014. Approximately 16 605 patients with PNETs and available vital status were identified. Survival was compared by race/ethnicity and socioeconomic status using Kaplan-Meier methods and Cox regression. RESULTS: There were no significant differences in survival between Non-Hispanic, White; Hispanic, White; or Non-Hispanic, Black patients on univariate analysis. Kaplan-Meier analysis showed that patients from communities with lower median household income and education level had worse survival (p < 0.001). Patients age less than 65 without insurance, similarly, had worse survival (p < 0.001). Multivariable modeling found no association between race/ethnicity and risk of mortality (p = 0.37). Lower median household income and lower education level were associated with increased mortality (p < 0.001). CONCLUSIONS: Unlike most other malignancies, race/ethnicity is not associated with survival differences in patients with PNETs. Patients with lower socioeconomic status had worse survival. The presence of identifiable health disparities in patients with PNETs represents a target for intervention and opportunity to improve survival in patients with this malignancy.


Assuntos
Carcinoma Ductal Pancreático/etnologia , Etnicidade/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , Tumores Neuroendócrinos/etnologia , Neoplasias Pancreáticas/etnologia , Fatores Socioeconômicos , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/terapia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
2.
Inorg Chem ; 54(7): 3125-33, 2015 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-25797500

RESUMO

The three new complexes Tp(Py)Ln(CH3CO2)2(H2O) (Ln = Eu (1), Gd(2), or Tb (3)) were prepared and characterized crystallographically. In the crystal lattices of these complexes, separate molecules are connected in infinite chains by π-stacking interactions. Complexes 1 and 3 display intense photoluminescence and triboluminescence (red and green respectively), while compound 3 exhibits electroluminescence commencing at 9 V in an ITO/PVK/3/Al device (ITO = indium-tin oxide, PVK = poly(N-vinylcarbazole)). A series of Eu/Tb-doped Gd compounds was prepared by cocrystallization from mixtures of 1 and 2 or 2 and 3, respectively. It was shown that π-stacking interactions are involved in increasing the efficiency of energy transfer from the gadolinium complex to emitting [Tp(Py)Eu](2+) or [Tp(Py)Tb](2+) centers, and this energy transfer occurs through hundreds of molecules, resembling the process of energy harvesting in chloroplast stacks.


Assuntos
Boratos/química , Complexos de Coordenação/química , Érbio/química , Gadolínio/química , Pirazóis/química , Térbio/química , Complexos de Coordenação/síntese química , Transferência de Energia , Elementos da Série dos Lantanídeos/química , Luminescência , Estrutura Molecular
3.
Photochem Photobiol Sci ; 12(2): 356-62, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23069900

RESUMO

Spectral and photochemical properties of ZnO nanocrystal solutions containing free nitronyl nitroxide radical 2-(o-hydroxyphenyl)-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl (Nit(o-OH)Ph) were studied. The ZnO photoluminescence quenching by Nit(o-OH)Ph was observed and analysis of the dependences of ZnO photoluminescence intensity on radical concentrations revealed the prevalence of a static mechanism for this process. The changes in spectral properties of colloidal ZnO nanocrystal solutions in the presence of a Nit(o-OH)Ph radical under illumination were studied. The nitronyl nitroxide was found to undergo photoinduced reduction to the corresponding hydroxylamine both via the excited-state interaction with ethanol and capturing of the ZnO conduction band electrons. Photoreduction of the radical was observed under illumination with light of λ > 460 nm in the presence of 4.2 nm ZnO nanocrystals, while no changes took place in the case of larger 4.8 nm ZnO nanocrystals. This pronounced size effect was interpreted in terms of much stronger spatial exciton confinement in the smaller ZnO nanocrystals favouring the irreversible electron transfer from the photoexcited radical.


Assuntos
Nanopartículas/química , Óxidos de Nitrogênio/química , Óxido de Zinco/química , Espectroscopia de Ressonância de Spin Eletrônica , Medições Luminescentes , Estrutura Molecular , Processos Fotoquímicos
4.
World J Gastrointest Surg ; 10(9): 95-106, 2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30622678

RESUMO

Pancreatic cancer (PC) induced cachexia is a complex metabolic syndrome associated with significantly increased morbidity and mortality and reduced quality of life. The pathophysiology of cachexia is complex and poorly understood. Many molecular signaling pathways are involved in PC and cachexia. Though our understanding of cancer cachexia is growing, therapeutic options remain limited. Thus, further discovery and investigation of the molecular signaling pathways involved in the pathophysiology of cachexia can be applied to development of targeted therapies. This review focuses on three main pathophysiologic processes implicated in the development and progression of cachexia in PC, as well as their utility in the discovery of novel targeted therapies. Skeletal muscle wasting is the most prominent pathophysiologic anomaly in cachectic patients and driven by multiple regulatory pathways. Several known molecular pathways that mediate muscle wasting and cachexia include transforming growth factor-beta (TGF-ß), myostatin and activin, IGF-1/PI3K/AKT, and JAK-STAT signaling. TGF-ß antagonism in cachectic mice reduces skeletal muscle catabolism and weight loss, while improving overall survival. Myostatin/activin inhibition has a great therapeutic potential since it plays an essential role in skeletal muscle regulation. Overexpression of insulin-like growth factor binding protein-3 (IGFBP-3) leads to increased ubiquitination associated proteolysis, inhibition of myogenesis, and decreased muscle mass in PC induced cachexia. IGFBP-3 antagonism alleviates muscle cell wasting. Another component of cachexia is profound systemic inflammation driven by pro-cachectic cytokines such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interferon gamma (INF-γ). IL-6 antagonism has been shown to reduce inflammation, reduce skeletal muscle loss, and ameliorate cachexia. While TNF-α inhibitors are clinically available, blocking TNF-α signaling is not effective in the treatment of cancer cachexia. Blocking the synthesis or action of acute phase reactants and cytokines is a feasible therapeutic strategy, but no anti-cytokine therapies are currently approved for use in PC. Metabolic alterations such as increased energy expenditure and gluconeogenesis, insulin resistance, fat tissue browning, excessive oxidative stress, and proteolysis with amino acid mobilization support tumor growth and the development of cachexia. Current innovative nutritional strategies for cachexia management include ketogenic diet, utilization of natural compounds such as silibinin, and supplementation with ω3-polyunsaturated fatty acids. Elevated ketone bodies exhibit an anticancer and anticachectic effect. Silibinin has been shown to inhibit growth of PC cells, induce metabolic alterations, and reduce myofiber degradation. Consumption of ω3-polyunsaturated fatty acids has been shown to significantly decrease resting energy expenditure and regulate metabolic dysfunction.

5.
J Oncol ; 2018: 6214838, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30631356

RESUMO

Membrane transporters fulfill essential roles in maintaining normal cellular function in health. In cancer, transporters likewise facilitate the aberrant characteristics typical of proliferating tumor cells. Pancreatic ductal adenocarcinoma is remarkable in its aggressiveness, and its metabolism is supported by a variety of membrane transporters. Glucose transporter 1 is upregulated in pancreatic cancer, enables rapid cellular uptake of glucose, and contributes to the invasiveness and metastatic ability of the disease. Likewise, the machinery of glycolysis, enzymes such as pyruvate kinase type M2 and hexokinase 2, is particularly active and ultimately leads to both lactate and tumor formation. Lactic acid channels and transporters include monocarboxylate transporters 1 and 4, connexin43, and CD147. In conjunction with glucose transporters and glycolytic metabolism, lactic acid transport helps perpetuate tumor cell metabolism and contributes to the formation of the unique tumor microenvironment in pancreatic cancer. These transporters may serve as potential therapeutic targets.

6.
Dalton Trans ; 46(11): 3457-3469, 2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28139794

RESUMO

A series of brightly luminescent new mononuclear TpPyLn(An)2(H2O) (where An- = carboxylate anion, Ln = Eu or Tb and TpPy- = tris(3-(2'-pyridyl)pyrazolyl)borate) and dinuclear (TpPyLn)2pma(MeOH)2 (Ln = Eu, Tb, pma4- = tetraanion of pyromellitic acid) complexes were prepared and characterized by X-ray crystallography. Within each series the compounds possess similar molecular structures, which differ only by the nature of the carboxylate anions. The quantum efficiencies for metal-centered emission of the complexes were up to 29(3)% for Eu3+ and 53(5)% for the Tb3+ compounds and significantly depend on the electronic structure of the additional ligand (i.e. the carboxylate). The aliphatic carboxylate compounds' luminescence quantum yields were all similar, but different from those for the aromatic ones. The complexes with trifluoroacetate and pentafluorobenzoate unexpectedly displayed lower quantum efficiencies compared to those with the corresponding non-fluorinated analogues. Energy transfer from Tb3+ to Eu3+ occurs in a mixture of (TpPyEu)(pma)(TbTpPy)(MeOH)2, (TpPyEu)2(pma)(MeOH)2 and (TpPyTb)2(pma)(MeOH)2 but is not very efficient. The Tb3+-compounds displayed green electroluminescence, and both the Eu3+ and Tb3+ complexes exhibited bright metal-centered red (Eu3+) or green (Tb3+) triboluminescence.

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