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1.
Proteomics ; 24(12-13): e2300281, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38171879

RESUMO

Glycosylation, the major post-translational modification of proteins, significantly increases the diversity of proteoforms. Glycans are involved in a variety of pivotal structural and functional roles of proteins, and changes in glycosylation are profoundly connected to the progression of numerous diseases. Mass spectrometry (MS) has emerged as the gold standard for glycan and glycopeptide analysis because of its high sensitivity and the wealth of fragmentation information that can be obtained. Various separation techniques have been employed to resolve glycan and glycopeptide isomers at the front end of the MS. However, differentiating structures of isobaric and isomeric glycopeptides constitutes a challenge in MS-based characterization. Many reports described the use of various ion mobility-mass spectrometry (IM-MS) techniques for glycomic analyses. Nevertheless, very few studies have focused on N- and O-linked site-specific glycopeptidomic analysis. Unlike glycomics, glycoproteomics presents a multitude of inherent challenges in microheterogeneity, which are further exacerbated by the lack of dedicated bioinformatics tools. In this review, we cover recent advances made towards the growing field of site-specific glycosylation analysis using IM-MS with a specific emphasis on the MS techniques and capabilities in resolving isomeric peptidoglycan structures. Furthermore, we discuss commonly used software that supports IM-MS data analysis of glycopeptides.


Assuntos
Glicopeptídeos , Glicosilação , Glicopeptídeos/análise , Glicopeptídeos/química , Glicopeptídeos/metabolismo , Humanos , Espectrometria de Mobilidade Iônica/métodos , Polissacarídeos/análise , Polissacarídeos/química , Polissacarídeos/metabolismo , Espectrometria de Massas/métodos , Proteômica/métodos , Processamento de Proteína Pós-Traducional , Animais , Glicômica/métodos , Glicoproteínas/química , Glicoproteínas/análise , Glicoproteínas/metabolismo
2.
J Magn Reson Imaging ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982805

RESUMO

BACKGROUND: Clinical importance of mitral annulus disjunction (MAD) is not well established. PURPOSE: Characterize a population of MAD all-comers diagnosed by cardiac magnetic resonance imaging (MRI). STUDY TYPE: Retrospective. POPULATION: MAD confirmed in 222 patients, age of 49.2 ± 19.3 years, 126 (56.8%) males. FIELD STRENGTH/SEQUENCE: 1.5 T and 3 T/steady-state free precession and inversion recovery. ASSESSMENT: Clinical history, outcomes, imaging, and arrhythmia data. MAD defined as a separation ≥2 mm between left ventricular myocardium and mitral annulus. Presence and pattern of late gadolinium enhancement (LGE) were analyzed. LGE in the papillary muscles and adjacent to MAD were identified as MAD related. Ventricular arrhythmias (VA) were grouped into non-sustained ventricular arrhythmias (NSVA) or sustained. Cardiovascular death assessed. STATISTICAL TESTS: Differences between baseline characteristics were compared. Univariate regression was used to investigate possible associations between ventricular arrhythmia and cardiovascular death with characteristics associated with the severity of MAD. A multivariable logistic regression included significant variables from the univariate analysis and was performed for MAD-related and global LGE. RESULTS: MAD extent 5.0 ± 2.6 mm. MV annulus expanded during systole for MAD ≥6 mm. Systolic expansion associated with prolapse, billowing, and curling. LGE present in 82 patients (36.9%). Twenty-three patients (10.4%) showed MAD-related LGE by three different observers. No association of LGE with MAD extent (P = 0.545) noted. Follow-up 4.1 ± 2.4 years. No sustained VA observed. In univariable analysis, NSVA was more prevalent in patients with MAD ≥6 mm (33.3% vs. 9.9%), but this was attenuated on multivariate analysis (P = 0.054). The presence of NSVA was associated with global LGE but not MAD-related LGE in isolation (P = 0.750). Three patients died of cardiovascular causes (1.4%) and none had MAD-related LGE. None died of sudden cardiac arrest. CONCLUSION: In patients referred for cardiac MRI, mitral valve dysfunction was associated with MAD severity. Scar was not related to the extent of MAD, but associated with NSVA. The risk of sustained arrhythmias and cardiovascular death was low in this population. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.

3.
Anal Chem ; 95(27): 10145-10148, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37382290

RESUMO

Mass spectrometry (MS) can unlock crucial insights into the intricate world of glycosylation analysis. Despite its immense potential, the qualitative and quantitative analysis of isobaric glycopeptide structures remains one of the most daunting hurdles in the field of glycoproteomics. The ability to distinguish between these complex glycan structures poses a significant challenge, hindering our ability to accurately measure and understand the role of glycoproteins in biological systems. A few recent publications described the use of collision energy (CE) modulation to improve structural elucidation, especially for qualitative purposes. Different linkages of glycan units usually demonstrate different stabilities under CID/HCD fragmentation conditions. Fragmentation of the glycan moiety produces low molecular weight ions (oxonium ions) that can serve as a structure-specific signature for specific glycan moieties; however, the specificity of these fragments has never been examined closely. Here, we particularly focused on N-glycoproteomics analysis and investigated fragmentation specificity using synthetic stable isotope-labeled N-glycopeptide standards. These standards were isotopically labeled at the reducing terminal GlcNAc, which allowed us to resolve fragments produced by the oligomannose core moiety and fragments generated from outer antennary structures. Our research identified the potential for false-positive structure assignments due to the occurrence of "Ghost" fragments resulting from single glyco unit rearrangement or mannose core fragmentation within the collision cell. To mitigate this issue, we have established a minimal intensity threshold for these fragments to prevent misidentification of structure-specific fragments in glycoproteomics analysis. Our findings provide a crucial step forward in the quest for more accurate and reliable glycoproteomics measurements.


Assuntos
Glicoproteínas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Glicoproteínas/química , Polissacarídeos/química , Glicopeptídeos/análise , Íons/química
4.
J Appl Toxicol ; 43(9): 1393-1405, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37055923

RESUMO

Produced water (PW) generated by oil companies is a highly impacting waste that contains chemicals such as metals and organic and inorganic compounds. Given its polluting potential, PW requires effective treatment before being discharged into the environment. Conventional treatments have limited efficiency in removing PW toxicity, so alternative approaches must be developed and standardized. In this context, treatment with adsorbent materials like magnetized vermiculite (VMT-mag) is highlighted. This work aimed to evaluate the efficiency of treatment with VMT-mag in reducing PW toxicity to aquatic biota. For this purpose, three aquatic species (the midge Chironomus riparius, the planarian Girardia tigrina, and the crustacean Daphnia magna) were exposed to untreated PW and to PW treated with VMT-mag at laboratory conditions. The assessed endpoints included mortality, growth, emergence, and developmental time of C. riparius; mortality, locomotion, feeding, and head regeneration of G. tigrina; and intrinsic population growth rate (r) and reproductive output of D. magna. The results showed that all the species exposed to raw PW were impaired: C. riparius had delayed development, G. tigrina had reduced locomotor activity and delayed head regeneration, and D. magna had reduced reproduction and delayed intrinsic population growth rate (r). Most of the analyzed parameters showed that treatment with VMT-mag diminished PW toxicity. Therefore, using VMT-mag to treat PW may be the key to reducing the PW effects on aquatic organisms.


Assuntos
Silicatos de Alumínio , Indústria de Petróleo e Gás , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Animais , Silicatos de Alumínio/química , Organismos Aquáticos , Daphnia , Água/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Testes de Toxicidade
5.
Proteomics ; 22(15-16): e2100322, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35700310

RESUMO

Glycosylation of viral proteins is required for the progeny formation and infectivity of virtually all viruses. It is increasingly clear that distinct glycans also play pivotal roles in the virus's ability to shield and evade the host's immune system. Recently, there has been a great advancement in structural identification and quantitation of viral glycosylation, especially spike proteins. Given the ongoing pandemic and the high demand for structure analysis of SARS-CoV-2 densely glycosylated spike protein, mass spectrometry methodologies have been employed to accurately determine glycosylation patterns. There are still many challenges in the determination of site-specific glycosylation of SARS-CoV-2 viral spike protein. This is compounded by some conflicting results regarding glycan site occupancy and glycan structural characterization. These are probably due to differences in the expression systems, form of expressed spike glycoprotein, MS methodologies, and analysis software. In this review, we recap the glycosylation of spike protein and compare among various studies. Also, we describe the most recent advancements in glycosylation analysis in greater detail and we explain some misinterpretation of previously observed data in recent publications. Our study provides a comprehensive view of the spike protein glycosylation and highlights the importance of consistent glycosylation determination.


Assuntos
COVID-19 , SARS-CoV-2 , Glicosilação , Humanos , Espectrometria de Massas/métodos , Polissacarídeos/química , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo
6.
Environ Res ; 213: 113641, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35716817

RESUMO

Several studies have shown that ingestion of microplastics causes adverse effects in aquatic organisms, including sediment-dwelling invertebrates. Most studies focus on evaluating the effects of plastic particles alone without testing the mediating effects of different natural stressors and thus lacking realistic exposure scenarios. The present study addresses the interactive effects of exposure to polyethylene microplastics (PE-MPs; 2.5 g/kg) in the midge Chironomus riparius life history traits under different temperatures (15, 20 and 25 °C), a salinity gradient (0, 1 and 3 g L-1 sodium chloride - NaCl) and different levels of food (0.5, 0.25 and 0.125 mg macerated fish food larva-1day-1). By the analyses of linear models and independent action models applied to different life-history traits, such as larval growth, development time and imagoes body weight, the present work reveals that under temperatures lower than 20 °C or severe food shortage (<0.25 mg macerated fish food larva-1day-1), microplastics' effects can be stronger than those observed at standard toxicity test conditions (20 °C and 0.5 mg food larva-1day-1). Additionally, we also found that, in general, toxicity induced by PE-MPs to C. riparius larvae was reduced under warmer temperature (25 °C) and salinity. As observed, MPs toxicity can be mediated by natural stressors, which underlines the importance of co-exposure studies. In this sense, these results contribute to a more accurate risk assessment of microplastics. Despite the complex interactions between microplastics and natural factors here tested, were not found evidence that the deleterious effects of PE-MPs on C. riparius life cycle history are aggravated under increased temperature, food shortage, or salinisation of freshwaters.


Assuntos
Chironomidae , Características de História de Vida , Poluentes Químicos da Água , Animais , Larva , Microplásticos , Plásticos/toxicidade , Polietileno/toxicidade , Poluentes Químicos da Água/análise
7.
Am J Hum Biol ; 34(9): e23781, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35866928

RESUMO

OBJECTIVES: This cross-sectional study investigated menopause status in relation to hand grip strength, standing balance, and rapid foot tapping. A secondary aim was to examine the relationship between physical performance and urban/rural residence with a focus on habitual daily tasks. METHODS: Maya and non-Maya women (40-60 years) were drawn from urban and rural sites in Campeche, Mexico (n = 543). Demographic, reproductive, and lifestyle information was collected in face-to-face interviews along with anthropometric and physical function measures. Linear regression was used to evaluate menopause status in relation to strength, balance, and foot tapping speed while adjusting for residence, ethnicity, and other variables. RESULTS: Hand grip strength was 22.5, 21.6, and 20.0 kg in pre-, peri-, and postmenopausal women, respectively, but menopause status was not significantly related to grip strength in models adjusted for age. Grip strength was negatively associated with age and socioeconomic index, and positively associated with height and weight, self-reported health, and hours/week spent grinding corn/making tortillas. Postural stability was 9.4, 6.9, and 5.6 s across menopause categories; and menopause status remained significant in adjusted models. The number of foot taps in 10 s was 35.7, 33.4, and 33.9 taps in pre-, peri-, and postmenopausal women. Parity was negatively associated with foot tapping in adjusted models. CONCLUSIONS: While age is a key predictor of physical function in women aged 40-60 years, menopausal status appears to have additional influences on postural control beyond age alone. Hours spent grinding corn/making tortillas were significantly associated with grip strength among rural women.


Assuntos
Força da Mão , Menopausa , Estatura , Estudos Transversais , Feminino , Humanos , México
8.
Ecotoxicol Environ Saf ; 207: 111375, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32987189

RESUMO

Freshwater sediments are a repository of microplastics (MPs) resulting from inland anthropogenic activities. Benthic invertebrates, particularly endobenthic sediment-ingesting species such as the annelid Lumbriculus variegatus (blackworm), are commonly found in contaminated sediments where they likely find and ingest MPs. In the present study, L. variegatus was exposed to concentrations between 0.51 and 20 g kg-1 dry sediment of four size-classes of irregularly-shaped polyethylene MPs (PE-MPs; size-class A: 32-63, B: 63-125, C: 125-250 and D: 250-500 µm) for 48 h to assess their sub-cellular responses to particles ingested, and for 28 days to determine chronic effects on worm's reproduction and biomass. After the short-term exposure (48 h), number of PE-MPs in blackworms' gut were related to MPs concentration in the sediment. In general, PE-MPs ingestion by blackworms induced depletion of their energy reserves (e.g., sugars in all size classes and lipids in the size-classes of PE-MPs > 125 µm), concomitant with the activation of antioxidant and detoxification mechanisms (increased level of total glutathione in all size-classes, and increased glutathione-S-transferase activity in PE-MPs > 250 µm), preventing lipid peroxidation. In addition, it was observed a reduction of aerobic energy production (decreased activity of the electron transport system) and a slight increase in neurotransmission (cholinesterase activity). After a long-term exposure (28 d), the presence and ingestion of PE-MPs did not affect reproduction and biomass of L. variegatus. The activation and efficiency of the antioxidant and detoxification mechanisms allied with the anatomy and physiology of L. variegatus, its feeding strategy and potentially dynamic ingestion/egestion capacity seem to be key features preventing MP deleterious effects under short- and chronic-exposures. Considering the MPs levels reported for freshwater sediments, and despite evidence of MPs ingestion and some sub-organismal effects, our results suggest no adverse impacts of PE-MPs contamination on L. variegatus populations fitness. This study applies an integrative approach in which data concerning the ingestion of different sized MPs and subsequent sub-cellular and apical responses are delivered, raising knowledge on endobenthic invertebrates' strategies to potentially overcome MP toxicity in field contaminated sites.


Assuntos
Microplásticos/toxicidade , Oligoquetos/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Ingestão de Alimentos , Água Doce , Sedimentos Geológicos , Oligoquetos/efeitos dos fármacos , Plásticos/toxicidade , Polietileno , Reprodução/efeitos dos fármacos
9.
Glycobiology ; 29(4): 307-319, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30726901

RESUMO

Successful application of potent antibody-based T-cell engaging immunotherapeutic strategies is currently limited mainly to hematological cancers. One major reason is the lack of well-characterized antigens on solid tumors with sufficient cancer specific expression. Aberrantly O-glycosylated proteins contain promising cancer-specific O-glycopeptide epitopes suitable for immunotherapeutic applications, but currently only few examples of such antibody epitopes have been identified. We previously showed that chimeric antigen receptor T-cells directed towards aberrantly O-glycosylated MUC1 can control malignant growth in a mouse model. Here, we present a discovery platform for the generation of cancer-specific monoclonal antibodies targeting aberrant O-glycoproteins. The strategy is based on cancer cell lines engineered to homogeneously express the truncated Tn O-glycoform, the so-called SimpleCells. We used SimpleCells of different cancer origin to elicit monoclonal antibodies with selectivity for aberrant O-glycoproteins. For validation we selected and characterized one monoclonal antibody (6C5) directed to a Tn-glycopeptide in dysadherin (FXYD5), known to be upregulated in cancer and promote metastasis. While dysadherin is widely expressed also in normal cells, we demonstrated that the 6C5 epitope is specifically expressed in cancer.


Assuntos
Anticorpos Monoclonais/análise , Anticorpos Monoclonais/biossíntese , Glicoproteínas/metabolismo , Neoplasias/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Epitopos/imunologia , Epitopos/metabolismo , Glicoproteínas/imunologia , Humanos , Camundongos , Neoplasias/imunologia , Neoplasias/patologia
10.
Am J Phys Anthropol ; 167(2): 282-290, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30159886

RESUMO

OBJECTIVES: The purpose of this study was to examine anti-Müllerian hormone (AMH) levels among women of Maya and non-Maya ancestry in the city of Campeche, Mexico. Levels of AMH can potentially predict age at menopause. Previous studies have indicated an early mean age at menopause among the Maya. MATERIALS AND METHODS: Women aged 40-60 (n = 97) participated in semistructured interviews, anthropometric measures, and blood samples. Maya/non-Maya ethnicity was determined by the last names, languages spoken, and birthplace of the woman, her parents, and her grandparents. AMH values were categorized as detectable (0.05-4.19 ng/mL) and undetectable (<0.05 ng/mL). Logistic regressions calculated odds ratios (OR) for undetectable AMH. RESULTS: Women were categorized as Maya (n = 44), not Maya (n = 39), or not able to be clearly defined (n = 14). In bivariate comparisons, women with detectable levels of AMH were younger, more likely to be pre-menopausal, and not Maya. Age, menopausal status, and ethnicity remained significant in a logistic regression models after controlling for age at menarche. Maya women were more than five times as likely to have nondetectable AMH levels as non-Maya women. DISCUSSION: Increasing age and progression through the menopausal transition were both associated with declining levels of AMH. The association between Maya ethnicity and a lower likelihood of detecting AMH is consistent with the early ages at menopause reported in previous studies. We considered a rapid life history model as an explanatory framework, and suggest, from an ecological perspective, that future research should consider measures of developmental stress that may compromise ovarian reserves.


Assuntos
Hormônio Antimülleriano/sangue , Indígenas Norte-Americanos/estatística & dados numéricos , Adulto , Estudos Transversais , Feminino , Humanos , Menopausa/fisiologia , México/epidemiologia , Pessoa de Meia-Idade
11.
Genes Chromosomes Cancer ; 56(3): 243-252, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27750403

RESUMO

Leukemia cell lines have been widely used in the hematology field to unravel mechanistic insights and to test new therapeutic strategies. Myelodysplastic syndromes (MDS) comprise a heterogeneous group of diseases that are characterized by ineffective hematopoiesis and frequent progress to acute myeloid leukemia (AML). A few cell lines have been established from MDS patients after progression to AML but their characterization is incomplete. Here we provide a detailed description of the immunophenotypic profile of the MDS-derived cell lines SKK-1, SKM-1, F-36P; and MOLM-13. Specifically, we analyzed a comprehensive panel of markers that are currently applied in the diagnostic routine for myeloid disorders. To provide high-resolution genetic data comprising copy number alterations and losses of heterozygosity we performed whole genome single nucleotide polymorphism-based arrays and included the cell line OHN-GM that harbors the frequent chromosome arm 5q deletion. Furthermore, we assessed the mutational status of 83 disease-relevant genes. Our results provide a resource to the MDS and AML field that allows researchers to choose the best-matching cell line for their functional studies. © 2016 Wiley Periodicals, Inc.


Assuntos
Biomarcadores Tumorais/genética , Aberrações Cromossômicas , Análise Citogenética/métodos , Imunofenotipagem/métodos , Leucemia Mieloide Aguda/genética , Mutação/genética , Síndromes Mielodisplásicas/genética , Progressão da Doença , Humanos , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/patologia , Células Tumorais Cultivadas
12.
Glycobiology ; 27(10): 920-926, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28673046

RESUMO

MUC16 is a large transmembrane mucin expressed on the apical surfaces of the epithelium covering the ocular surface, respiratory system and female reproductive tract. The transmembrane mucin is overexpressed by ovarian carcinomas, it is one of the most frequently used diagnostic markers for the disease and it is considered a promising target for immunotherapeutic intervention. Immunodetection of the mucin has to date been through antibodies that recognize its exceptionally large ectodomain. Similar to other membrane anchored mucins, MUC16 has a short cytoplasmic tail (CT), but studies of the biological relevance of the C-terminal domain of MUC16 has been limited by lack of availability of monoclonal antibodies that recognize the native CT. Here, we report the development of a novel monoclonal antibody to the CT region of the molecule that recognizes native MUC16 and its enzymatically released CT region. The antibody is useful for immunoprecipitation of the released CT domain as demonstrated with the OVCAR3 ovarian cancer cell line and can be used for detailed cytolocalization in cells as well as in frozen sections of ocular surface and uterine epithelium.


Assuntos
Anticorpos Monoclonais/imunologia , Biomarcadores Tumorais/imunologia , Antígeno Ca-125/imunologia , Proteínas de Membrana/imunologia , Animais , Antígeno Ca-125/química , Feminino , Células HeLa , Humanos , Proteínas de Membrana/química , Camundongos , Camundongos Endogâmicos BALB C , Domínios Proteicos
13.
Mol Cell Proteomics ; 14(6): 1616-29, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25813380

RESUMO

Circulating O-glycoproteins shed from cancer cells represent important serum biomarkers for diagnostic and prognostic purposes. We have recently shown that selective detection of cancer-associated aberrant glycoforms of circulating O-glycoprotein biomarkers can increase specificity of cancer biomarker assays. However, the current knowledge of secreted and circulating O-glycoproteins is limited. Here, we used the COSMC KO "SimpleCell" (SC) strategy to characterize the O-glycoproteome of two gastric cancer SimpleCell lines (AGS, MKN45) as well as a gastric cell line (KATO III) which naturally expresses at least partially truncated O-glycans. Overall, we identified 499 O-glycoproteins and 1236 O-glycosites in gastric cancer SimpleCells, and a total 47 O-glycoproteins and 73 O-glycosites in the KATO III cell line. We next modified the glycoproteomic strategy to apply it to pools of sera from gastric cancer and healthy individuals to identify circulating O-glycoproteins with the STn glycoform. We identified 37 O-glycoproteins in the pool of cancer sera, and only nine of these were also found in sera from healthy individuals. Two identified candidate O-glycoprotein biomarkers (CD44 and GalNAc-T5) circulating with the STn glycoform were further validated as being expressed in gastric cancer tissue. A proximity ligation assay was used to show that CD44 was expressed with the STn glycoform in gastric cancer tissues. The study provides a discovery strategy for aberrantly glycosylated O-glycoproteins and a set of O-glycoprotein candidates with biomarker potential in gastric cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Glicoproteínas/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Neoplasias Gástricas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Linhagem Celular Tumoral , Feminino , Glicoproteínas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , N-Acetilgalactosaminiltransferases/sangue , Proteoma , Neoplasias Gástricas/sangue , Polipeptídeo N-Acetilgalactosaminiltransferase
14.
Adv Exp Med Biol ; 987: 1-12, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28971442

RESUMO

Hyperthermia, the procedure of raising the temperature of a part of or the whole body above normal for a defined period of time, is applied alone or as an adjunctive with various established cancer treatment modalities such as radiotherapy and chemotherapy. In this study used a method for inducing hyperthermia in solid tumors with a combination of gold macro rod (GR) and ultrasound, the feasibility of this technique was described only with computational models and in vitro. The Ehrlich tumor, derived from a mouse adenocarcinoma, has been used to investigate the bio-heat transfer and the effect of gold rods irradiated with ultrasound. The in vivo measurements demonstrated that the technique inhibited more 80% of the tumor growth in both experimental models tested. These results not only confirm the bio heat transfer to tissue as predicted by analytical calculation and in vitro measurements, but are also proved to be a potential alternative to kill cancer cells.


Assuntos
Hipertermia Induzida/métodos , Neoplasias Experimentais/terapia , Terapia por Ultrassom/métodos , Animais , Linhagem Celular Tumoral , Terapia Combinada , Modelos Animais de Doenças , Humanos , Masculino , Camundongos Endogâmicos BALB C , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral
15.
Adv Exp Med Biol ; 987: 119-138, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28971453

RESUMO

PURPOSE: The aim of this study was to analyze feasibility (in vitro and in vivo) the use of hyperthermia produced by gold rods irradiated with ultrasound and their combination with chemotherapy with doxorubicin. MATERIALS AND METHODS: initially was determined the cell viability and Hsp70 levels after treatment by gold rods irradiated with ultrasound (GR+U) in cell culture. The pretreatment with GR+U combined with doxorubicin (DOX) was evaluated from IC50, caspase-3 expression and mechanisms of cell death by electron microscopy. For evaluate the in vivo effects was used solid Ehrlich carcinoma (SEC) Tumor. The animals received three treatments with the combination of GR+U+DOX over 16 days. RESULTS: The cell viability was completely inhibited after 40 min of treatment with GR+U and significant increases the expression of HSP70 was only observed after 10 min of treatment. GR+U+DOX presented significant reduction of IC50 representing 50.7%, 76.5% 45.2% and 46.6% for cell lines K562, NCI-H292, Hep-2 and MCF-7 respectively. GR+U+DOX presented significant reduction of IC50 representing 50.7%, 76.5% 45.2% and 46.6% for cell lines K562, NCI-H292, Hep-2 and MCF-7 respectively. The caspase-3 level and ultraestructural analysis showed that treatment with GR+U+DOX enhances induction of apoptosis. Pretreatment with GR+U combined with doxorubicin (1 mg) showed 87% inhibition against SEC. and no showed cardiotoxic effect. CONCLUSIONS: The combined treatment of GR+U and DOX exhibit synergistic characteristics observed by increasing the efficiency of doxorubicin.


Assuntos
Doxorrubicina/farmacologia , Hipertermia Induzida/métodos , Neoplasias Experimentais/terapia , Terapia por Ultrassom/métodos , Animais , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , Ouro , Proteínas de Choque Térmico HSP70/metabolismo , História Antiga , Temperatura Alta , Humanos , Células K562 , Células MCF-7 , Masculino , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Ondas Ultrassônicas
16.
Ecotoxicol Environ Saf ; 143: 210-216, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28551578

RESUMO

Despite the frequent detection of organic ultraviolet-filters (UV-filters) in freshwater sediments, there is a lack of ecotoxicological data undermining a correct risk assessment for these emerging contaminants. The present study assessed the effects of three of the most commonly used UV-filters (benzophenone-3 - BP3; 3-(4-methylbenzylidene)camphor - 4-MBC and octocrylene - OC) on Chironomus riparius life history and biochemical responses. Standard ecotoxicological assays confirmed that all compounds impaired growth of C. riparius larvae and induced developmental effects such as delayed emergence and a reduction of imagoes weight. Concerning the biochemical responses analysed no evidences of oxidative damage in lipids or neurotoxicity (tested assessing acetylcholinesterase activity) were observed for any of the tested compounds. However, 4-MBC exposure induced a decrease in catalase activity and an increase in glutathione-S-transferase activity at 14.13mg/Kg while OC exposure caused an increase in total glutathione levels at 0.23 and 18.23mg/Kg. Exposure to all UV-filters tested, increased energy consumption on C. riparius with significant differences above 1.00mg/Kg for BP3, 0.09mg/Kg for 4-MBC and 2.13mg/Kg for OC. These results suggest that environmental relevant concentrations of UV-filters can cause deleterious effects to aquatic benthic species, such as C. riparius, and call for further research concerning effects of organic UV-filters on natural invertebrate communities and ecosystem functioning.


Assuntos
Acrilatos/toxicidade , Benzofenonas/toxicidade , Cânfora/análogos & derivados , Chironomidae/efeitos dos fármacos , Protetores Solares/toxicidade , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Cânfora/toxicidade , Catalase/metabolismo , Chironomidae/enzimologia , Feminino , Glutationa Transferase/metabolismo , Larva/efeitos dos fármacos , Larva/enzimologia , Masculino
17.
Ecotoxicol Environ Saf ; 137: 240-246, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27978451

RESUMO

The insecticide thiamethoxam (TMX) is a systemic neonicotinoid widely used for pest control in several agricultural crops. TMX mimics the action of acetylcholine causing uncontrolled muscular contraction eventually leading to insect death. TMX is being found in freshwater ecosystems at concentrations of up to 225µg/L. Still, chronic toxicity data for freshwater invertebrates is limited. Therefore, the aim of this study was to evaluate the acute and chronic effects (at organismal and biochemical levels) of TMX on the freshwater insect Chironomus riparius. C. riparius life history responses were significantly affected by TMX exposure, namely with a decrease in growth and delay in emergence. Concerning the biochemical responses, after a short exposure (48h) to TMX, our results showed that low concentrations of TMX significantly reduced CAT activity and LPO levels of C. riparius. No effects were observed in AChE, GST and ETS activities. Effects in terms of survival, development rates and biochemical responses of C. riparius exposed to low concentrations of TMX observed in this study suggest potential deleterious effects of this neonicotinoid on aquatic insects inhabiting freshwaters environments near agricultural areas.


Assuntos
Chironomidae/efeitos dos fármacos , Inseticidas/toxicidade , Nitrocompostos/toxicidade , Oxazinas/toxicidade , Tiazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Análise de Variância , Animais , Chironomidae/crescimento & desenvolvimento , Água Doce/análise , Insetos/efeitos dos fármacos , Invertebrados/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Estágios do Ciclo de Vida/efeitos dos fármacos , Neonicotinoides , Tiametoxam
18.
Ecotoxicology ; 26(4): 534-546, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28353160

RESUMO

Populations inhabiting metal-impacted freshwater systems located nearby industrial and urban areas may be under intense selection. The present study aims to address two fundamental microevolutionary aspects of metal contamination in the midge Chironomus riparius (Meigen): Are populations inhabiting historically metal contaminated sites genetically adapted to metals? And, are populations from these sites genetically eroded? To answer these questions, C. riparius populations were sampled from three sites with well-known histories of metal contamination and three nearby-located references. Genetic adaptation to metals was investigated through acute and chronic exposures to cadmium (Cd), after rearing all populations for at least six generations under laboratory clean conditions. Genetic diversity was estimated based on the allelic variation of seven microsatellite markers. Results showed higher acute tolerance to Cd in populations originating from metal contaminated sites compared to their respective references and significant differences in two out of three pairwise comparisons. However, there was a mismatch between acute and chronic tolerance to Cd with results of the partial life-cycle tests suggesting fitness costs under control clean conditions in two metal-adapted populations. Despite no evidences of genetic erosion in populations sampled from metal contaminated sites, our results suggest genetically inherited tolerance to Cd in populations inhabiting historically contaminated sites. These findings lend support to the use of C. riparius as a model organism in evolutionary toxicology and highlight the importance of coupling measures of neutral genetic diversity with assessments of chemical tolerance of populations for a better understanding of contaminant-induced adaptation and evolutionary processes.


Assuntos
Chironomidae/fisiologia , Metais/toxicidade , Poluentes Químicos da Água/toxicidade , Adaptação Fisiológica , Animais , Evolução Biológica , Variação Genética , Larva , Estágios do Ciclo de Vida , Repetições de Microssatélites
19.
20.
Health Qual Life Outcomes ; 14: 20, 2016 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-26872726

RESUMO

BACKGROUND: Health-related quality of life (HRQoL) is an important outcome to assess the impact of cancer. This article examines the psychometric properties of the European Portuguese self-report version of the Pediatric Quality of Life Inventory™ Cancer Module (PedsQL™ 3.0 Cancer Module) in children and adolescents with cancer. METHODS: The participants, 332 children/adolescents diagnosed with cancer (8-18 years old), completed measures to assess HRQoL (PedsQL™ 3.0 Cancer Module and DISABKIDS Chronic Generic Measure; DCGM-12) and anxiety (Revised Children's Manifest Anxiety Scale - second edition; RCMAS-2). A subsample (n = 52) completed the PedsQL™ 3.0 Cancer Module a second time following one-week. The pediatric oncologists completed the Intensity of Treatment Rating Scale 3.0 (ITR 3.0). RESULTS: For the whole sample, the PedsQL™ 3.0 Cancer Module demonstrated good item discrimination (rs = .30 to .54). The confirmatory factor analysis testing the presence of eight first-order factors loading significantly in a second-order factor revealed an acceptable fit (CFI = .91; RMSEA = .05). The correlation of PedsQL™ 3.0 Cancer Module with DCGM-12 (rs = .17 to .58), and with RCMAS-2 (rs = -.16 to-.51) attested convergent validity. This inventory demonstrated minimally acceptable to very good internal consistency (αs = .65 to .87) and temporal stability (ICCs = .61 to .81). CONCLUSIONS: These findings demonstrate that the European Portuguese self-report version of the PedsQL™ 3.0 Cancer Module is a valid and reliable instrument for assessing HRQoL in pediatric cancer.


Assuntos
Neoplasias/psicologia , Psicometria/instrumentação , Qualidade de Vida/psicologia , Adolescente , Criança , Análise Fatorial , Feminino , Humanos , Masculino , Portugal , Reprodutibilidade dos Testes , Autorrelato , Índice de Gravidade de Doença
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