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1.
Contact Dermatitis ; 91(1): 45-53, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38602297

RESUMO

BACKGROUND: Allergic contact dermatitis (ACD) from rubber glove usage is usually caused by rubber additives such as the accelerators. However, in analyses of the suspected gloves, ordinary rubber allergens are not always found. Accelerator-free rubber gloves are available, but some patients with accelerator allergy do not tolerate them and might also be patch test positive to them. OBJECTIVES: To identify and chemically characterize a new allergen, 2-cyanoethyl dimethyldithiocarbamate (CEDMC), in rubber gloves. We describe two patient cases: patient 1 that led us to the identification of CEDMC and patient 2 with occupational ACD caused by CEDMC. METHODS: The patients were examined with patch testing including baseline and rubber series, and their own rubber gloves. High-performance liquid chromatography (HPLC) was used for chemical analysis of rubber gloves. The allergen was synthesized and identified by nuclear magnetic resonance, mass spectrometry and infrared spectrometry, and tested on patient 2. RESULTS: CEDMC was identified by HPLC in a nitrile glove associated with hand eczema in patient 1. Patient 2 whose nitrile gloves contained CEDMC was patch test positive to CEDMC. CONCLUSIONS: CEDMC is a new contact allergen in nitrile gloves and probably forms during vulcanization from residual monomer acrylonitrile and rubber additives.


Assuntos
Dermatite Alérgica de Contato , Dermatite Ocupacional , Luvas Protetoras , Nitrilas , Testes do Emplastro , Humanos , Dermatite Alérgica de Contato/etiologia , Dermatite Alérgica de Contato/diagnóstico , Luvas Protetoras/efeitos adversos , Dermatite Ocupacional/etiologia , Dermatite Ocupacional/diagnóstico , Nitrilas/efeitos adversos , Dimetilditiocarbamato/efeitos adversos , Masculino , Dermatoses da Mão/induzido quimicamente , Feminino , Pessoa de Meia-Idade , Alérgenos/efeitos adversos , Alérgenos/análise , Adulto , Cromatografia Líquida de Alta Pressão , Ditiocarb/efeitos adversos , Ditiocarb/química
2.
Int J Mol Sci ; 25(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673758

RESUMO

Animal tumors serve as reasonable models for human cancers. Both human and animal tumors often reveal triplet EPR signals of nitrosylhemoglobin (HbNO) as an effect of nitric oxide formation in tumor tissue, where NO is complexed by Hb. In search of factors determining the appearance of nitrosylhemoglobin (HbNO) in solid tumors, we compared the intensities of electron paramagnetic resonance (EPR) signals of various iron-nitrosyl complexes detectable in tumor tissues, in the presence and absence of excess exogenous iron(II) and diethyldithiocarbamate (DETC). Three types of murine tumors, namely, L5178Y lymphoma, amelanotic Cloudman S91 melanoma, and Ehrlich carcinoma (EC) growing in DBA/2 or Swiss mice, were used. The results were analyzed in the context of vascularization determined histochemically using antibodies to CD31. Strong HbNO EPR signals were found in melanoma, i.e., in the tumor with a vast amount of a hemorrhagic necrosis core. Strong Fe(DETC)2NO signals could be induced in poorly vascularized EC. In L5178Y, there was a correlation between both types of signals, and in addition, Fe(RS)2(NO)2 signals of non-heme iron-nitrosyl complexes could be detected. We postulate that HbNO EPR signals appear during active destruction of well-vascularized tumor tissue due to hemorrhagic necrosis. The presence of iron-nitrosyl complexes in tumor tissue is biologically meaningful and defines the evolution of complicated tumor-host interactions.


Assuntos
Ditiocarb , Hemoglobinas , Óxido Nítrico , Animais , Óxido Nítrico/metabolismo , Ditiocarb/farmacologia , Ditiocarb/química , Camundongos , Hemoglobinas/metabolismo , Hemoglobinas/química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Detecção de Spin/métodos , Neovascularização Patológica/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Camundongos Endogâmicos DBA , Compostos Ferrosos/química
3.
J AOAC Int ; 107(4): 582-591, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38430462

RESUMO

BACKGROUND: Busulfan is the most effective medication for treating chronic myelogenous or granulocytic leukemia because it has cytotoxic properties that harm or kill hematopoietic cells. It cannot absorb light in the Ultraviolet range due to its structure. Because of this, it is very challenging to quantify using traditional HPLC coupled with UV/Photodiode Array detectors. So, using sodium diethyldithiocarbamate, a derivatization method was developed to quantify related impurities. A significant unknown impurity was identified in derivatized samples of busulfan and a noticeably high percentage level was discovered during routine drug testing. OBJECTIVE: We aimed to isolate, and characterize the unknown impurity observed in the samples and to identify its root cause. METHODS: Preparative HPLC was used to isolate the unidentified, derivatized impurity, and 1H NMR, 13C NMR, and MS were used to decipher its structural components. RESULTS: The spectral characterization data analysis showed that the unknown impurity was related to busulfan. Additionally, it was noted that the impurity developed as a result of the residual buffer used to prepare the derivatizing reagent. CONCLUSION: The isolated impurity was found to be same as comparable to that found in busulfan drug substances, according to the results of the characterization tools. An alternative method of reagent preparation was optimized and deemed satisfactory because the buffer used in reagent preparation is the only factor contributing to the formation of impurities. HIGHLIGHTS: Using cutting-edge analytical characterization tools, it was possible to explain the structural characteristics of an unknown impurity and discover that it was a novel impurity, which undoubtedly contributes to the comprehension of drug substance reaction properties.


Assuntos
Bussulfano , Contaminação de Medicamentos , Bussulfano/análise , Bussulfano/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética/métodos , Ditiocarb/química , Espectrometria de Massa com Cromatografia Líquida
4.
Nanomedicine (Lond) ; 19(11): 979-994, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578787

RESUMO

Background: Cancer stem cells' (CSCs) resistance to 5-fluorouracil (Fu), which is the main obstacle in treating colon cancer (CC), can be overcome by ferroptosis. The latter, herein, can be triggered by FeO nanoparticles (inducer of iron accumulation) and diethyldithiocarbamate-inhibited glutathione system and aldehyde dehydrogenase (ALDH1A1-maintained stemness, therapeutic resistance and metastasis). Materials & methods: Nanocomplex of FeO nanoparticles and diethyldithiocarbamate (FD) was used in combination with Fu to investigate its potential synergistic anti-CSC influence using CC spheroid models. Results: In Fu + FD-treated spheroids, the strongest growth inhibition, the highest cell death percentage, and the lowest CD133+-CSCs percentage and stemness gene expressions (e.g., drug efflux transporter), and the strongest antimetastatic effect were recorded with high synergistic indexes. Conclusion: Fu + FD represents effective combination therapy for chemoresistant CC cells.


[Box: see text].


Assuntos
Neoplasias do Colo , Ditiocarb , Sinergismo Farmacológico , Fluoruracila , Células-Tronco Neoplásicas , Esferoides Celulares , Humanos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Neoplasias do Colo/metabolismo , Fluoruracila/farmacologia , Fluoruracila/química , Ditiocarb/farmacologia , Ditiocarb/química , Esferoides Celulares/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Nanopartículas Magnéticas de Óxido de Ferro/química , Proliferação de Células/efeitos dos fármacos
5.
Salud pública Méx ; 56(5): 473-491, sep.-oct. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-733321

RESUMO

Objetivo. Evaluar las tendencias de mortalidad por cáncer en México entre 1980 y 2011. Material y métodos. Se calcularon las tasas de mortalidad ajustadas por edad y sexo para todos los cánceres y para las 15 localizaciones más frecuentes mediante el método directo y tomando como población estándar la población mundial de 2010. Las tendencias en las tasas de mortalidad y el cambio porcentual anual para cada tipo de cáncer se estimaron a través de un modelo de regresión joinpoint. Resultados. A partir de 2004 y como consecuencia de la reducción de la mortalidad por cáncer de pulmón (-3.2% en hombres y -1.8% en mujeres), estómago (-2.1% en hombres y -2.4% en mujeres) y cérvix (-4.7%), se observó una disminución significativa (~1% anual) en la mortalidad por cáncer en general tanto en el grupo de todas las edades como en el de 35 a 64 años para ambos sexos. La mortalidad por otros cánceres como el de mama y el de ovario, en las mujeres o el de próstata, en los hombres, mostró un aumento sostenido. Conclusiones. Algunas de las reducciones en la mortalidad por cáncer pueden ser parcialmente atribuidas a la efectividad de los programas de prevención establecidos. Sin embargo, se requiere implementar registros adecuados de cáncer con base poblacional para evaluar el impacto real de estos programas, así como diseñar y evaluar intervenciones innovadoras que permitan desarrollar políticas de prevención más costo-efectivas.


Objective. To evaluate trends in cancer mortality in Mexico between 1980-2011. Material and methods. Through direct method and using World Population 2010 as standard population, mortality rates for all cancers and the 15 most frequent locations, adjusted for age and sex were calculated. Trends in mortality rates and annual percentage change for each type of cancer were estimated by joinpoint regression model. Results. As a result of the reduction in mortality from lung cancer (-3.2% -1.8% in men and in women), stomach (-2.1% -2.4% in men and in women) and cervix (-4.7%); since 2004 a significant (~1% per year) decline was observed in cancer mortality in general, in all ages, and in the group of 35-64 years of both sexes. Other cancers such as breast and ovarian cancer in women; as well as for prostate cancer in men, showed a steady increase. Conclusions. Some of the reductions in cancer mortality may be partially attributed to the effectiveness of prevention programs. However, adequate records of population-based cancer are needed to assess the real impact of these programs; as well as designing and evaluating innovative interventions to develop more cost-effective prevention policies.


Assuntos
Animais , Masculino , Ratos , Endotoxemia/metabolismo , Intestino Delgado/metabolismo , Rim/metabolismo , Fígado/metabolismo , Óxido Nítrico/análise , Ditiocarb/química , Ditiocarb/farmacocinética , Endotoxinas/toxicidade , Compostos Férricos/química , Intestino Delgado/efeitos dos fármacos , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Óxido Nítrico/sangue , Óxido Nítrico/metabolismo , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Marcadores de Spin , Detecção de Spin/métodos , Fatores de Tempo
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