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1.
Neurochem Res ; 43(3): 591-599, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29497903

RESUMO

This study aimed to study the protective effect of (2R,4R)-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC), a selective metabotropic glutamate receptor agonist, against hippocampal neuronal apoptosis induced by seizures in a rat model of pilocarpine-induced epilepsy. The Morris water maze test was used to assess the spatial memory abilities of epileptic rats with or without 2R,4R-APDC treatment. TUNEL assay was performed to examine neuronal apoptosis in hippocampus. Western blot was conducted to evaluate changes in the levels of caspase-3 and caspase-9 in hippocampus. Real-time PCR was used to determine the levels of microRNA-128 (miR-128) in hippocampus. The results of the Morris water maze test showed that the 2R,4R-APDC treatment reduced the escape latencies and swimming lengths of rats after seizures. The TUNEL assay showed that 2R,4R-APDC significantly counteracted seizure-induced cell apoptosis. The western blot confirmed this finding, demonstrating that the levels of cleaved caspase-3 and cleaved caspase-9 were potently decreased by 2R,4R-APDC in rat hippocampus after seizures. In addition, 2R,4R-APDC upregulated miR-128 expression levels in the hippocampus. A miR-128 mimic or inhibitor decreased or increased the percentage of TUNEL-positive cells in rats after seizures and 2R,4R-APDC treatment, respectively. The levels of both cleaved caspase-3 and cleaved caspase-9 were decreased in hippocampus exposed to the miR-128 mimic, whereas they were markedly increased in miR-128 inhibitor-treated hippocampus. In conclusion, 2R,4R-APDC protected hippocampal cells from cell apoptosis after seizures, possibly by upregulating miR-128.


Assuntos
MicroRNAs/metabolismo , Prolina/análogos & derivados , Receptores de Glutamato Metabotrópico/agonistas , Regulação para Cima/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Agonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/metabolismo , Masculino , Memória/efeitos dos fármacos , Prolina/farmacologia , Ratos Sprague-Dawley , Convulsões/tratamento farmacológico , Convulsões/metabolismo
2.
J Pediatr ; 163(4): 1014-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23769505

RESUMO

OBJECTIVE: To identify the maternal and infant risk factors associated with hospital admission in the first year and estimate the associated costs of infant hospitalization. STUDY DESIGN: Data from the Perinatal Data Collection for 599753 liveborn infants born in New South Wales, Australia, 2001-2007 were linked to hospital admission data. Logistic regression models were used to investigate the association between maternal and infant characteristics and admission to hospital once, and more than once in the first year; and average costs for total hospital admissions were calculated. RESULTS: Almost 15% of infants were admitted to hospital once and 4.6% had multiple admissions. Gestational age <37 weeks was most strongly associated with admission to hospital once, and severe neonatal morbidity was most strongly associated with multiple admissions (aOR 2.60; 95% CI 2.47-2.75). Infants born <39 weeks gestational age, to adolescent mothers, mothers who smoke, are not married, or had a planned delivery also have an increased risk of multiple admissions. Infants with severe neonatal morbidity contributed 27% of total infant hospital costs. With each increasing week of gestational age the mean annual cost decreased on average 10% and 27% for infants with and without neonatal morbidity respectively. CONCLUSIONS: Infants born with severe neonatal morbidity have increased hospitalizations in the first year; however, the majority of burden on health system is by infants without severe neonatal morbidity. Hospitalizations, and associated costs, increased with decreasing gestational age, even for infants born at 37-38 weeks. Targeted public health strategies may reduce the burden of infant hospitalizations.


Assuntos
Admissão do Paciente/economia , Admissão do Paciente/estatística & dados numéricos , Feminino , Idade Gestacional , Custos de Cuidados de Saúde , Custos Hospitalares , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Doenças do Recém-Nascido/economia , Recém-Nascido Prematuro , Modelos Logísticos , Masculino , Mães , New South Wales , Fatores de Risco
3.
JHEP Rep ; 4(10): 100552, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36119722

RESUMO

Background & Aims: Population-level trends and factors associated with HBV-related decompensated cirrhosis (DC), hepatocellular carcinoma (HCC), and liver-related mortality are crucial to evaluate the impacts of therapeutic interventions. Methods: Trends in HBV-DC and -HCC diagnoses and liver-related mortality in New South Wales, Australia, were determined through linkage of HBV notifications (1993-2017) to hospital admissions (2001-2018), mortality (1993-2018), and cancer registry (1994-2014) databases. Late HBV notification was defined as notification at or within 2 years of a DC or HCC diagnosis. Cox proportional-hazards regression and multivariable logistic regression analyses were performed to evaluate associated factors. Results: Among 60,660 people with a HBV notification, 1,276 (2.0%) DC and 1,087 (1.8%) HCC diagnoses, and 1,219 (2.0%) liver-related deaths were documented. Since the early 2000s, the number of DC and HCC diagnoses increased; however, age-standardised incidence decreased from 2.64 and 1.95 in 2003 to 1.14 and 1.09 per 1,000 person-years in 2017, respectively. Similarly, age-standardised liver mortality decreased from 2.60 in 2003 to 1.14 per 1,000 person-years in 2017. Among people with DC and HCC diagnoses, late HBV notification declined from 41% and 40% between 2001-2009 to 29% and 25% in 2010-2018, respectively. Predictors of DC diagnosis included older age (birth <1944, adjusted hazard ratio [aHR] 2.06, 95% CI 1.57-2.69), alcohol use disorder (aHR 4.82, 95% CI 3.96-5.87) and HCV co-infection (aHR 1.88, 95% CI 1.53-2.31). Predictors of HCC diagnosis included older age (birth <1944, aHR 3.94, 95% CI 2.91-5.32) and male sex (aHR 3.79, 95% CI 3.05-4.71). Conclusion: In an era of improved antiviral therapies, the risk of HBV-related liver morbidity and mortality has declined. HCV co-infection and alcohol use disorder are key modifiable risk factors associated with the burden of HBV. Lay summary: Rising hepatitis B-related morbidity and mortality is a major public health concern. However, the development of highly effective medicines against hepatitis B virus (HBV) has brought renewed optimism for its elimination by 2030. This study shows a steady decline in HBV-related liver morbidity and mortality in New South Wales, Australia. Moreover, late hepatitis notification has also declined, allowing individuals with HBV to have access to timely antiviral treatment. Despite this, hepatitis C co-infection and alcohol use disorder are key modifiable risk factors associated with HBV disease burden. To attain the desired benefits from highly effective antiviral treatment, managing comorbidities, including hepatitis C and high alcohol use, must improve among individuals with hepatitis B.

4.
Cells ; 10(6)2021 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204067

RESUMO

Age-related macular degeneration (AMD) is a retinal disease leading to impaired vision. Cigarette smoke increases the risk for developing AMD by causing increased reactive oxygen species (ROS) production and damage in the retinal pigment epithelium (RPE). We have previously shown that the cigarette tar component hydroquinone causes oxidative stress in human RPE cells. In the present study, we investigated the propensity of hydroquinone to induce the secretion of interleukin (IL)-1ß and IL-18. The activation of these cytokines is usually regulated by the Nucleotide-binding domain, Leucine-rich repeat, and Pyrin domain 3 (NLRP3) inflammasome. ARPE-19 cells were exposed to hydroquinone, and cell viability was monitored using the lactate dehydrogenase (LDH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide salt (MTT) assays. Enzyme-linked immunosorbent assays (ELISAs) were used to measure the levels of proinflammatory cytokines IL-1ß and IL-18 as well as NLRP3, caspase-1, and poly (ADP-ribose) polymerase (PARP). Hydroquinone did not change IL-1ß release but significantly increased the secretion of IL-18. Cytoplasmic NLRP3 levels increased after the hydroquinone treatment of IL-1α-primed RPE cells, but IL-18 was equally released from primed and nonprimed cells. Hydroquinone reduced the intracellular levels of PARP, which were restored by treatment with the ROS scavenger N-acetyl-cysteine (NAC). NAC concurrently reduced the NLRP3 levels but had no effect on IL-18 release. In contrast, the NADPH oxidase inhibitor ammonium pyrrolidinedithiocarbamate (APDC) reduced the release of IL-18 but had no effect on the NLRP3 levels. Collectively, hydroquinone caused DNA damage seen as reduced intracellular PARP levels and induced NLRP3-independent IL-18 secretion in human RPE cells.


Assuntos
Dano ao DNA , Hidroquinonas/farmacologia , Inflamassomos/metabolismo , Interleucina-18/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Humanos
5.
ACS Appl Mater Interfaces ; 13(8): 9500-9519, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32603135

RESUMO

Aptamers are oligonucleotide sequences with a length of about 25-80 bases which have abilities to bind to specific target molecules that rival those of monoclonal antibodies. They are attracting great attention in diverse clinical translations on account of their various advantages, including prolonged storage life, little batch-to-batch differences, very low immunogenicity, and feasibility of chemical modifications for enhancing stability, prolonging the half-life in serum, and targeted delivery. In this Review, we demonstrate the emerging aptamer discovery technologies in developing advanced techniques for producing aptamers with high performance consistently and efficiently as well as requiring less cost and resources but offering a great chance of success. Further, the diverse modifications of aptamers for therapeutic applications including therapeutic agents, aptamer-drug conjugates, and targeted delivery materials are comprehensively summarized.


Assuntos
Aptâmeros de Nucleotídeos/uso terapêutico , Portadores de Fármacos/química , Animais , Aptâmeros de Nucleotídeos/química , Ensaios de Triagem em Larga Escala/instrumentação , Ensaios de Triagem em Larga Escala/métodos , Humanos , Dispositivos Lab-On-A-Chip , Lipossomos/química , Nanopartículas Metálicas/química , Peptídeos/química , Técnica de Seleção de Aptâmeros/instrumentação , Técnica de Seleção de Aptâmeros/métodos
6.
J Control Release ; 325: 304-322, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32652110

RESUMO

In the past decades, nanosized drug delivery systems based on N-(2-hydroxypropyl)methacrylamide copolymers (pHPMA) have gained increasing attention in nanomedicine field due to their hydrophilicity, versatility, biocompatibility, non-toxicity, and non-immunogenicity. Indeed, pHPMA nanosystems with various controlled drug release capabilities inside targeted tissues or cells have been intensively studied. This paper summarizes recent advances in the design and application of pHPMA conjugates with specific antibodies or their fragments, focusing predominantly on the systems for the cancer therapy, particularly, the mechanisms of action of therapeutic antibodies, the approaches of their modification and subsequent attachment of pHPMA and their conjugates with diverse active moieties. Finally, we highlight the major biomedical applications of these antibody-polymer-drug conjugates and consider directions of possible development over the coming decade.


Assuntos
Sistemas de Liberação de Medicamentos , Metacrilatos , Nanomedicina , Polímeros
7.
J Control Release ; 328: 160-170, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-32860930

RESUMO

B-cell non-Hodgkin lymphomas (B-NHL) represent the most common type of hematologic malignancies in the Western hemisphere. The therapy of all B-NHL is based on the combination of different genotoxic cytostatics and anti-CD20 monoclonal antibody (mAb) rituximab. Unfortunately, many patients relapse after the mentioned front-line treatment approaches. The therapy of patients with relapsed/refractory (R/R) B-NHL represents an unmet medical need. We designed, developed and tested novel actively targeted hybrid mAb-polymer-drug conjugate (APDC) containing anti-CD20, anti-CD38 or anti-CD19 mAbs. Biocompatible copolymers based on N-(2-hydroxypropyl)methacrylamide (HPMA) with cytostatic agent doxorubicin attached via stimuli-sensitive hydrazone bond were employed for the mAb grafting. Anti-lymphoma efficacy of the APDC nanotherapeutics was evaluated in vivo on a panel of three patient-derived lymphoma xenografts derived from two patients with R/R B-NHL and one patient with so far untreated B-NHL. In both PDX models derived from patients with R/R B-NHL, the targeting with anti-CD38 antibody daratumumab demonstrated highly improved anti-lymphoma efficacy compared to the targeting with anti-CD20 rituximab, two experimental anti-CD19 antibodies and non-targeted controls. The results represent a proof-of-concept of a new algorithm of personalized anti-tumor therapy based on highly innovative APDC biomaterials.


Assuntos
Antineoplásicos , Linfoma não Hodgkin , Preparações Farmacêuticas , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Humanos , Linfoma não Hodgkin/tratamento farmacológico , Polímeros/uso terapêutico , Rituximab
9.
Anal Chim Acta ; 789: 58-64, 2013 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23856230

RESUMO

This study proposes the dual electromembrane extraction followed by high performance liquid chromatography for selective separation-preconcentration of Cr(VI) and Cr(III) in different environmental samples. The method was based on the electrokinetic migration of chromium species toward the electrodes with opposite charge into the two different hollow fibers. The extractant was then complexed with ammonium pyrrolidinedithiocarbamate for HPLC analysis. The effects of analytical parameters including pH, type of organic solvent, sample volume, stirring rate, time of extraction and applied voltage were investigated. The results showed that Cr(III) and Cr(VI) could be simultaneously extracted into the two different hollow fibers. Under optimized conditions, the analytes were quantified by HPLC instrument, with acceptable linearity ranging from 20 to 500 µg L(-1) (R(2) values≥0.9979), and repeatability (RSD) ranging between 9.8% and 13.7% (n=5). Also, preconcentration factors of 21.8-33 that corresponded to recoveries ranging from 31.1% to 47.2% were achieved for Cr(III) and Cr(VI), respectively. The estimated detection limits (S/N ratio of 3:1) were less than 5.4 µg L(-1). Finally, the proposed method was successfully applied to determine Cr(III) and Cr(VI) species in some real water samples.


Assuntos
Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromo/análise , Poluentes Químicos da Água/análise , Ânions/isolamento & purificação , Cátions/isolamento & purificação , Fracionamento Químico/instrumentação , Cromo/química , Cromo/isolamento & purificação , Técnicas Eletroquímicas , Eletrodos , Desenho de Equipamento , Concentração de Íons de Hidrogênio , Limite de Detecção , Microextração em Fase Líquida/métodos , Pirrolidinas/química , Reprodutibilidade dos Testes , Rios/química , Solventes/química , Tiocarbamatos/química
10.
Environ Toxicol Pharmacol ; 36(3): 858-64, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23981376

RESUMO

In present study the lead (Pb) levels has been assessed by analyzing the scalp hair and blood samples of mentally retarded/intellectual disabled (MR/ID) children of both genders, age ranged 3-8 years. For comparative purpose, healthy age matched children were also selected. The cloud point extraction of Pb from digested biological samples was carried out by complexed with ammonium pyrrolidinedithiocarbamate. The complexed analyte was subsequently isolated from the aqueous matrix in the micelles of a non-ionic surfactant (Triton X-114). Dilution of the surfactant-rich phase with acidified ethanol was performed after phase separation, and the Pb content was measured by flame atomic absorption spectrometer. Factors affecting the cloud point extraction were evaluated and optimized. The proposed procedure allowed the determination of lead in certified standard and real samples with detection limits of 0.834µgL(-) and enhancement factor 55. The results were compared with those of healthy children have same age, socioeconomic status and residential areas.


Assuntos
Deficiência Intelectual/sangue , Intoxicação do Sistema Nervoso por Chumbo na Infância/sangue , Chumbo/análise , Análise de Variância , Criança , Pré-Escolar , Contagem de Eritrócitos , Feminino , Cabelo/química , Humanos , Indicadores e Reagentes , Deficiência Intelectual/psicologia , Testes de Inteligência , Chumbo/sangue , Intoxicação do Sistema Nervoso por Chumbo na Infância/psicologia , Masculino , Micro-Ondas , Fatores de Risco , Espectrofotometria Atômica , Inquéritos e Questionários
11.
Chemosphere ; 93(6): 939-45, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23790829

RESUMO

In this research, toxicological safety of two newly developed methods for the treatment of landfill leachate from the Piskornica (Croatia) sanitary landfill was investigated. Chemical treatment procedure combined chemical precipitation with CaO followed by coagulation with ferric chloride and final adsorption by clinoptilolite. Electrochemical treatment approach included pretreatment with ozone followed by electrooxidation/electrocoagulation and final polishing by microwave irradiation. Cell viability of untreated/treated landfill leachate was examined using fluorescence microscopy. Cytotoxic effect of the original leachate was obtained for both exposure periods (4 and 24 h) while treated samples showed no cytotoxic effect even after prolonged exposure time. The potential DNA damage of the untreated/treated landfill leachate was evaluated by the comet assay and cytokinesis-block micronucleus (CBMN) assay using either human or plant cells. The original leachate exhibited significantly higher comet assay parameters compared to negative control after 24 h exposure. On the contrary, there was no significant difference between negative control and chemically/electrochemically treated leachate for any of the parameters tested. There was also no significant increase in either CBMN assay parameter compared to the negative control following the exposure of the lymphocytes to the chemically or electrochemically treated landfill leachate for both exposure periods while the original sample showed significantly higher number of micronuclei, nucleoplasmic bridges and nuclear buds for both exposure times. Results suggest that both methods are suitable for the treatment of such complex waste effluent due to high removal efficiency of all measured parameters and toxicological safety of the treated effluent.


Assuntos
Plantas/efeitos dos fármacos , Eliminação de Resíduos/métodos , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/toxicidade , Linhagem Celular , Ensaio Cometa , Croácia , Monitoramento Ambiental , Humanos , Testes para Micronúcleos
12.
Anal Chim Acta ; 804: 37-49, 2013 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-24267061

RESUMO

Selenium is an essential element for the normal cellular function of living organisms. However, selenium is toxic at concentrations of only three to five times higher than the essential concentration. The inorganic forms (mainly selenite and selenate) present in environmental water generally exhibit higher toxicity (up to 40 times) than organic forms. Therefore, the determination of low levels of different inorganic selenium species in water is an analytical challenge. Solid-phase extraction has been used as a separation and/or preconcentration technique prior to the determination of selenium species due to the need for accurate measurements for Se species in water at extremely low levels. The present paper provides a critical review of the published methods for inorganic selenium speciation in water samples using solid phase extraction as a preconcentration procedure. On the basis of more than 75 references, the different speciation strategies used for this task have been highlighted and classified. The solid-phase extraction sorbents and the performance and analytical characteristics of the developed methods for Se speciation are also discussed.


Assuntos
Selênio/isolamento & purificação , Extração em Fase Sólida/métodos , Água/química , Limite de Detecção , Selênio/classificação
13.
Anal Chim Acta ; 789: 1-16, 2013 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23856225

RESUMO

The use of magnetic materials in solid phase extraction has received considerable attention in recent years taking into account many advantages arising from the inherent characteristics of magnetic particles. Magnetic solid phase extraction (MSPE) methodology overcomes problems such as column packing and phase separation, which can be easily performed by applying an external magnetic field. The use of magnetic particles in automatic systems is growing over the last few years making the on-line operation of MSPE a promising technique in the frame of green chemistry. This article aims to provide all recent progress in the research of novel magnetic materials as sorbents for metal preconcentration and determination coupled with different detection systems as well as their implementation in sequential injection and microfluidic systems. In addition, a description of preparation, characterization as well as applications of various types of magnetic materials, either with organic or inorganic coating of the magnetic core, is presented. Concluding remarks and future trends are also commented.


Assuntos
Magnetismo , Metais/análise , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Técnicas Analíticas Microfluídicas , Sistemas On-Line , Dióxido de Silício/química , Zircônio/química
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