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1.
J Wound Care ; 33(10): 756-770, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39388207

RESUMO

OBJECTIVE: Several national and international guidelines recommend lipidocolloid technology with a nano-oligosaccharide factor (TLC-NOSF) dressings (UrgoStart dressing range, Laboratoires Urgo, France) for treating patients with chronic wounds. However, these dressings are still often reported as second-line options, potentially leading to loss of opportunity for patients and additional costs for payers. This review aimed to explore the reported wound healing and patient outcomes as well as the related costs when the dressings were used as first-line treatment in patients with different types of chronic wounds. METHOD: A systematic review of the literature was conducted. Databases (MEDLINE, Embase, Emcare, and Google Scholar) were searched up to 1 February 2024, without any language or time period limitations. Studies were eligible if the evaluated dressings had been used as a first-line treatment for chronic wounds, that is, as an integral part of the standard of care (SoC) at the patient's first presentation and/or in recent wounds. The main evaluation criteria included: wound healing rate; time to reach wound closure; change in patients' quality of life (QoL); and associated costs. The quality of evidence of the included studies was appraised using well-recognised risk-of-bias tools suitable for different study designs. A narrative synthesis describes the findings in three sections depending on the type of comparison. This report followed the principles of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: A total of 17 studies published between 2017 and 2024 met the eligibility criteria. A comparative analysis between TLC-NOSF dressings and standard dressings, both of which were used as first-line treatment, was reported in nine studies. A comparative analysis between the use of TLC-NOSF dressings as first-line and second-line treatments was reported in eight studies, and five studies reported a systematic use of the TLC-NOSF dressing as first-line treatment without a control group. Overall, the included studies had a relatively low risk of bias for the respective types of evidence. Data of 10,191 patients of both sexes and different age groups with a total of 10,203 wounds (diabetic foot ulcers, leg ulcers, pressure injuries, and other types of chronic wounds) were included in the analysis: 7775 treated with the evaluated dressing and 2428 treated with a comparator dressing. The data suggested that using TLC-NOSF as a first-line treatment for chronic wounds consistently resulted in significantly higher healing rates, shorter healing times, and cost savings compared with standard dressings used under similar conditions. Real-life evidence confirmed the results obtained in clinical trials and economic models, within similar ranges, regardless of the settings involved or of the characteristics of the patients and wounds treated. The wound healing rates ranged around 70-80% by week 20/24 and time-to-heal was reported on average around seven weeks, with slightly longer times reported in wounds with a more severe prognosis. Furthermore, the dressings were shown to improve patient QoL, and were well tolerated and accepted, supporting a wider adoption approach. CONCLUSION: The results of this review are aligned with the current guidelines recommending the use of TLC-NOSF dressings in the treatment of patients with chronic wounds. They support its wider implementation as a first-line treatment and as an integral part of SoC for these wounds in the daily practice of all centres involved in their management.


Assuntos
Cicatrização , Humanos , Doença Crônica , Curativos Hidrocoloides , Ferimentos e Lesões/terapia , Bandagens , Qualidade de Vida
2.
Biomacromolecules ; 24(3): 1209-1219, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36802451

RESUMO

Simultaneous sustained release of cancer vaccines and immunomodulators may effectively trigger durable immune responses and avoid multiple administrations. Here, we established a biodegradable microneedle (bMN) based on a biodegradable copolymer matrix made of polyethylene glycol (PEG) and poly(sulfamethazine ester urethane) (PSMEU). This bMN was applied to the skin and slowly degraded in the epidermis/dermis layers. Then, the complexes composed of a positively charged polymer (DA3), cancer DNA vaccine (pOVA), and toll-like receptor 3 agonist poly(I/C) were synchronously released from the matrix in a pain-free manner. The whole microneedle patch was fabricated with two layers. The basal layer was formed using polyvinyl pyrrolidone/polyvinyl alcohol that could be rapidly dissolved upon applying the microneedle patch to the skin, whereas the microneedle layer was formed by complexes encapsulating biodegradable PEG-PSMEU, which was stuck at the injection site for sustained release of therapeutic agents. According to the results, 10 days is the time for the complexes to be completely released and express specific antigens in antigen-presenting cells in vitro and in vivo. It is noteworthy that this system could successfully elicit cancer-specific humoral immune responses and inhibit metastatic tumors in the lungs after a single shot of immunization.


Assuntos
Vacinas Anticâncer , Neoplasias , Humanos , Preparações de Ação Retardada , Pele , Adjuvantes Imunológicos , Polímeros , Polietilenoglicóis , Agulhas
3.
J Environ Manage ; 347: 119204, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37804634

RESUMO

This paper is likely the first attempt to empirically investigate the direct effect of geopolitical risk on sustainable development goals (SDGs). We employ a newly developed SDG index along with its 17 sub-indices from the United Nations to capture various aspects of sustainable development. On a panel sample covering 41 countries from 2015 to 2021, we find that elevated geopolitical tensions can hinder the progress towards achieving sustainable development goals. This result is robust to various model specifications and estimation approaches. Further analyses show that the two dimensions affected are Decent Work and Economic Growth (SDG8) and Climate Action (SDG13). Heterogeneity test finds that the negative effect of geopolitical risks is only present in countries highly dependent on natural resources. More importantly, improvements in institutional quality could partially offset the detrimental effect of geopolitical risks on sustainable development goals. Therefore, this study provides important implications for policymakers in devising measures to maintain the progress to achieve SDGs in the era of rising global uncertainties.


Assuntos
Saúde Global , Desenvolvimento Sustentável , Recursos Naturais , Desenvolvimento Econômico , Clima , Objetivos
4.
Eur J Orthop Surg Traumatol ; 33(6): 2595-2599, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36715762

RESUMO

INTRODUCTION: After centromedullary nailing (CMN) of 4-parts (4P) cephalo-tuberositary fractures of the proximal humerus (PH), shoulder immobilization for a few weeks is usual, although no scientific justification does support this attitude, nor the duration of immobilization. The objective of this study was to assess the impact of early mobilization after CMN of PH 4P fractures on clinical, radiological outcomes and complication rates. The hypothesis was that early mobilization would not lead to a deterioration in results or an increase in the complication rate. MATERIALS AND METHODS: All patients operated on for a 4P-PH fracture by CMN in our institution between 2010 and 2018 were included retrospectively. 2 groups were formed according to the duration of post-operative immobilization of the shoulder: 0-2 weeks (group A) and 3-6 weeks (group B). All patients had a clinical examination (Range of motion ROM and Constant score) and X-rays of the shoulder at least 24 months of follow-up. 58 patients (average age 66 years (39-89)) were included, with 25 in group A and 33 in group B. RESULTS: The average follow-up was 38.5 (24-73) months. The active ROM at the last follow-up was: active anterior elevation 149° (80°-180°) in group A versus 134 (60°-180°) in group B (p = 0.099); active external rotation 145° (15°-70°) in group A versus 42° (15-70°) in group B (p = 0.6). The Absolute Mean Constant score was 78.29 for Group A (45-100) versus 68.59 points (45-96) for Group B (p = 0.065). Regarding complications: in group A, we found 2 retractile capsulitis, 2 pseudarthrosis and 2 osteonecrosis of the humeral head. In group B, we found 5 retractile capsulitis, 1 infection of the surgical site, 3 osteonecrosis of the humeral head and 1 pseudarthrosis. CONCLUSION: Early mobilization after CMN of 4P-PH fractures did not lead to an increase in the complications rate and in particular secondary displacements or osteonecrosis. There was a trend toward improved clinical outcomes with early mobilization, although this trend was not statistically significant. EVIDENCE LEVEL: IV, retrospective study.


Assuntos
Fixação Intramedular de Fraturas , Fraturas do Úmero , Osteonecrose , Pseudoartrose , Fraturas do Ombro , Humanos , Idoso , Fixação Intramedular de Fraturas/efeitos adversos , Fixação Intramedular de Fraturas/métodos , Estudos Retrospectivos , Ombro , Pseudoartrose/etiologia , Deambulação Precoce , Úmero , Fraturas do Ombro/diagnóstico por imagem , Fraturas do Ombro/cirurgia , Cabeça do Úmero , Osteonecrose/etiologia , Fraturas do Úmero/etiologia , Resultado do Tratamento
5.
Br J Cancer ; 127(12): 2118-2124, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36224404

RESUMO

BACKGROUND: Female thyroid cancer survivors are more likely to have a higher risk of breast cancer compared to the general population, and the underlying causes are yet to be understood. The potential role of I-131 treatment on this association remains controversial. METHODS: We pooled individual data of women who were treated for differentiated thyroid cancer from 1934 to 2005 in France, Italy and Sweden. Standardized incidence ratios (SIRs) for breast cancer were estimated by comparison with age, sex and calendar-year expected values of the general population in each country. We estimated breast cancer risk in relation to I-131 treatment using time-dependent Poisson models. RESULTS: Of 8475 women (mean age at diagnosis: 45 years, range 2-90 years), 335 were diagnosed with breast cancer [SIR = 1.52, 95% confidence interval (CI): 1.36-1.69] during a median follow-up time of 12.7 years since diagnosis. Overall, breast cancer risk did not differ between women treated or not with I-131 (relative risk=1.07, 95% CI 0.84-1.35). However, breast cancer risk increased with increasing cumulative I-131 activity, without significant departure from linearity (excess relative risk per 100 mCi=17%, 95% CI: 2% to 38%). The higher risk associated with a cumulative I-131 activity of ≥100 mCi and ≥400 mCi was translated into 4 (95% CI -4 to 13) and 42 (95% CI -8 to 93) excess breast cancer cases per 10,000 person-years, respectively. CONCLUSIONS: An elevated risk was observed for the highest cumulative administered activity (>=400 mCi), and a significant dose-dependent association was observed among thyroid cancer survivors who were treated with I-131. However, overall, I-131 treatment might only explain partly the increase in breast cancer risk among female thyroid cancer survivors.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Neoplasias da Glândula Tireoide , Feminino , Humanos , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Radioisótopos do Iodo/efeitos adversos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/radioterapia , Risco , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/radioterapia
6.
Small ; 18(37): e2201730, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35957542

RESUMO

Interface engineering is one of the promising strategies for the long-term stabilization of perovskite solar cells (PSCs), preventing chemical decomposition induced by external agents and promoting fast charge transfer. Recently, MXenes-2D structured transition metal carbides and nitrides with various functionalization (O, -F, -OH) have demonstrated high potential for mastering the work function in halide perovskite absorbers and have significantly improved the n-type charge collection in solar cells. This work demonstrates that MXenes allow for efficient stabilization of PSCs besides improving their performances. A mixed composite bathocuproine:MXene, that is, (BCP:MXene) interlayer, is introduced at the interface between an electron-transport layer (ETL) and a metal cathode in the p-i-n device structure. The investigation demonstrates that the use of BCP:MXene interlayer slightly increases the power conversation efficiency (PCE) for PSCs (from 16.5 for reference to 17.5%) but dramatically improves the out of Glove-Box stability. Under ISOS-L-2 light soaking stress at 63 ± 1.5 °C, the T80 (time needed to reduce efficiency down to 80% of the initial one) period increases from 460 to > 2300 hours (h).

7.
World Econ ; 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35601729

RESUMO

At the centre of the multi-dimensional impact of the COVID-19 pandemic, the shortage of medical supplies in countries with weaker healthcare systems significantly reduced the effectiveness of national and international public health interventions. Using a database of test-kit trade flows and barriers, we estimate the price responsiveness of test-kit demand in a global sample of countries. These estimates allow us to investigate the degree to which import tariffs by leading producers could result in a disruption in global supply chains, price increases, and welfare loss. Simulation experiments indicate that the combination of rising demand for test kits and import dependence magnifies the impact of trade barriers on consumer welfare and this impact is more profound for developing countries.

8.
J Environ Manage ; 297: 113351, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34325363

RESUMO

This study revisits the nexus between energy consumption and economic growth by considering several energy use types (i.e., total energy, fossil fuel energy, and renewable energy). For this purpose, a dynamic fixed effects (DFE) estimator is applied to the autoregressive distributed lag (ARDL) model built on an extended version of the neoclassical production function. This study examines a global sample of 107 countries during 1996-2014, classified into three subsamples of countries based on income level. Overall, the findings show that, in the short run, the use of total energy and fossil fuel energy significantly and positively contribute to higher income in total and per-capita terms. However, the growth effects of renewable energy consumption appear to vary across subsamples. In the long run, the impacts of energy on economic growth are mostly insignificant, supporting the view that conservative energy policies do not harm economic growth.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Fontes Geradoras de Energia , Energia Renovável , Cimentos de Resina
9.
Electrophoresis ; 41(23): 1980-1990, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32856726

RESUMO

In this study, the development of our purpose-made capacitively coupled contactless conductivity detection (C4 D) for CE is reported. These systems have been employed as a simple, versatile, and cost-effective analytical tool. CE-C4 D devices, whose principle is based on the control of the ion movements under an electrical field, can be constructed even with a modest financial budget and limited infrastructure. A featured application was developed for quality control of antimicrobial drugs using CE-C4 D, with most recent work on determination of aminoglycoside and glycopeptide antibiotics being communicated. For aminoglycosides, the development of CE-C4 D methods was adapted to two categories. The first one includes drugs (liquid or powder form) for intravenous injection, containing either amikacin, streptomycin, kanamycin A, or kanamycin B. The second one covers drugs for eye drops (liquid or ointment form), containing either neomycin, tobramycin, or polymyxin. The CE-C4 D method development was also made for determination of some popular glycopeptide antibiotics in Vietnam, including vancomycin and teicoplanin. The best detection limit achieved using the developed CE-C4 D methods was 0.5 mg/L. Good agreement between results from CE-C4 D and the confirmation method (HPLC- Photometric Diode Array ) was achieved, with their result deviations less than 8% and 13% for aminoglycoside and glycopeptide antibiotics, respectively.


Assuntos
Antibacterianos , Eletroforese Capilar/métodos , Aminoglicosídeos/análise , Aminoglicosídeos/química , Aminoglicosídeos/normas , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/normas , Condutividade Elétrica , Eletroforese Capilar/economia , Eletroforese Capilar/instrumentação , Desenho de Equipamento , Glicopeptídeos/análise , Glicopeptídeos/química , Glicopeptídeos/normas , Limite de Detecção , Modelos Lineares , Controle de Qualidade , Reprodutibilidade dos Testes , Vietnã
10.
Bioprocess Biosyst Eng ; 43(6): 971-980, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32008095

RESUMO

Salinity (NaCl) stress treatment is a strategy to induce lipid accumulation in microalgae. This study aimed to investigate the effect of a combination of two salts (NaCl/CaCl2) on lipid productivity of Chlamydomonas reinhardtii. C. reinhardtii was cultured in a two-stage culture comprising 9-day active growth in C medium followed by 3-day salt stress in C medium with various concentrations of NaCl (50‒200 mM)/CaCl2 (100 mM). In salt stress stage, NaCl (200 mM), CaCl2 (100 mM), and the NaCl/CaCl2 mixture inhibited growth but increased the lipid content in C. reinhardtii in comparison with NaCl (0, 50, and 100 mM) conditions. Combinatorial treatment with 100 mM NaCl/100 mM CaCl2 resulted in the highest lipid content (73.4%) and lipid productivity (10.9 mg/L/days), being 3.5- and 2.1-fold, respectively, in salt-free control conditions, and 1.8- and 1.5-folds, respectively, with 200 mM NaCl. Furthermore, 100 mM NaCl/100 mM CaCl2 treatment markedly upregulated glycerol-3-phosphate dehydrogenase (GPDH), lysophosphatidic acid acyltransferase (LPAAT), and diacylglycerol acyltransferase (DAGAT), which are involved in lipid accumulation in C. reinhardtii. The upregulation of these genes with 100 mM NaCl/100 mM CaCl2 resulted in the highest lipid content in C. reinhardtii. Therefore, stress treatment using two salts, 100 mM NaCl/100 mM CaCl2, is a potentially promising strategy to enhance lipid productivity in microalgae.


Assuntos
Cloreto de Cálcio/farmacologia , Chlamydomonas reinhardtii/crescimento & desenvolvimento , Lipídeos/biossíntese , Pressão Osmótica/efeitos dos fármacos , Cloreto de Sódio/farmacologia
11.
Mol Vis ; 25: 215-221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30996590

RESUMO

Purpose: Retinoblastoma (RB) is a rare childhood malignant disorder caused by the biallelic inactivation of the RB1 gene. Early diagnosis and identification of carriers of heritable mutations in RB1 can improve disease outcome and management. In this study, we present the spectrum of mutations in the RB1 gene in Vietnamese patients with RB. Methods: Tumor RNA from 50 probands with RB, including 12 bilateral and 38 unilateral cases, was extracted. cDNA, after reverse transcription, was sequenced to identify the RNA mutation of the RB1 gene. At the genomic DNA level, mutational analysis of all RB1 exons, exon-intron boundaries, and the promoter region was conducted using PCR and direct sequencing. Multiplex ligation-dependent probe amplification (MLPA) analysis was performed for patients for whom the first two results were negative. For patients for whom either the sequencing or MLPA results were positive for a tumor mutation, patients' and their parents' blood DNA was analyzed to determine the germline mutation. Results: Forty-one different kinds of RB1 tumor mutations were identified in 41 probands (82.0%), including 11 of 12 bilateral cases (91.7%) and 30 of 38 unilateral cases (78.9%). The majority of the detected mutations were nonsense (15 different kinds), followed by frameshift (11 kinds), and splice site mutations (nine kinds). Each splice site mutation was confirmed to create a deletion of the corresponding exon with RNA sequencing. The single promoter mutation c.-197G>A was reported previously; however, both missense mutations identified in exon 6 (c.601G>C: p.A201P) and exon 22 (c.2264T>C: p.F755S) were novel. Gross deletions were detected with MLPA in three probands. The detection rate of germline mutations in bilateral and unilateral cases with mutations were 81.8% and 30.0%, respectively. Only one father out of the 20 parents tested was positive for a germline mutation. Conclusions: Mutations in the RB1 gene in Vietnamese patients were heterogeneous and highly prevalent with pathogenic truncated mutations. With advancement in therapeutics, early detection of RB is important for eye salvation.


Assuntos
Mutação , Retina/metabolismo , Neoplasias da Retina/genética , Proteínas de Ligação a Retinoblastoma/genética , Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética , Povo Asiático , Pré-Escolar , Análise Mutacional de DNA , Éxons , Feminino , Expressão Gênica , Humanos , Lactente , Íntrons , Masculino , Regiões Promotoras Genéticas , Retina/patologia , Neoplasias da Retina/etnologia , Neoplasias da Retina/patologia , Retinoblastoma/etnologia , Retinoblastoma/patologia
12.
Rev Med Virol ; 28(6): e2005, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30109914

RESUMO

We systematically searched and meta-analyzed the epidemiological characteristics, frequency of clinical signs, and outcomes of dengue-associated hemophagocytic lymphohistiocytosis. Ten electronic databases were searched systematically plus manual search of reference lists to identify relevant articles published until May 2017. The highest number of reported cases were from South-East Asia region (62 cases), followed by Western Pacific region (20 cases), and America (31 cases). The term "dengue hemorrhagic fever" predominated in studies that used the World Health Organization 1997 definition (59.7%), whereas "severe dengue" predominated in studies using the World Health Organization 2009 definition (76.8%). Among 122 cases, fever, splenomegaly, hepatomegaly, anemia, thrombocytopenia, and serum ferritin ≥500 µg/L were likely to report by articles representing by large sample size. The pooled proportion of these findings were as follows: fever 97.2%, hepatomegaly 70.2%, splenomegaly 78.4%, thrombocytopenia 90.1%, anemia 76.0%, and serum ferritin ≥500 µg/L 97.1%. This study highlighted a high case fatality rate (14.6%) and co-infection among dengue hemophagocytic lymphohistiocytosis patients. We suggest that long fever duration, persistent thrombocytopenia, elevated serum ferritin, and lactate dehydrogenase levels could be good diagnostic indicators for dengue-associated hemophagocytic syndrome. Bone marrow aspiration could be used as one criterion for diagnosis but is not obligatory. Further research is needed to examine the possible risk difference for development of hemophagocytic syndrome and to explore potential relationships between specific dengue classifications and dengue-associated hemophagocytic syndrome.


Assuntos
Dengue/complicações , Linfo-Histiocitose Hemofagocítica/epidemiologia , Linfo-Histiocitose Hemofagocítica/patologia , América/epidemiologia , Sudeste Asiático/epidemiologia , Humanos , Linfo-Histiocitose Hemofagocítica/mortalidade , Ilhas do Pacífico/epidemiologia , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento
14.
Biomacromolecules ; 19(8): 3536-3548, 2018 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-30005160

RESUMO

Despite great potential, the delivery of genetic materials into cells or tissues of interest remains challenging owing to their susceptibility to nuclease degradation, lack of permeability to the cell membrane, and short in vivo half-life, which severely restrict their widespread use in therapeutics. To surmount these shortcomings, we developed a bioinspired in situ-forming pH- and temperature-sensitive injectable hydrogel depot that could control the delivery of DNA-bearing polyplexes for versatile biomedical applications. A series of multiblock copolymer, comprised of water-soluble poly(ethylene glycol) (PEG) and pH- and temperature-responsive poly(sulfamethazine ester urethane) (PSMEU), has been synthesized as in situ-forming injectable hydrogelators. The free-flowing PEG-PSMEU copolymer sols at high pH and room temperature (pH 8.5, 23 °C) were transformed to stable gel at the body condition (pH 7.4, 37 °C). Physical and mechanical properties of hydrogels, including their degradation rate and viscosity, are elegantly controlled by varying the composition of urethane ester units. Subcutaneous administration of free-flowing PEG-PSMEU copolymer sols to the dorsal region of Sprague-Dawley rats instantly formed hydrogel depot. The degradation of the hydrogel depot was slow at the beginning and found to be bioresorbable after two months. Cationic protein or DNA-bearing polyplex-loaded PEG-PSMEU copolymer sols formed stable gel and controlled its release over 10 days in vivo. Owing to the presence of urethane linkages, the PEG-PSMEU possesses excellent adhesion strength to wide range of surfaces including glass, plastic, and fresh organs. More importantly, the hydrogels effectively adhered on human skin and peeled easily without eliciting an inflammatory response. Subcutaneous implantation of PEG-PSMEU copolymer sols effectively sealed the ruptured skin, which accelerated the wound healing process as observed by the skin appendage morphogenesis. The bioinspired in situ-forming pH- and temperature-sensitive injectable adhesive hydrogel may provide a promising platform for myriad biomedical applications as controlled delivery vehicle, adhesive, and tissue regeneration.


Assuntos
Adesivos/química , Técnicas de Transferência de Genes , Hidrogéis/química , Cicatrização/efeitos dos fármacos , Adesivos/administração & dosagem , Adesivos/farmacologia , Administração Cutânea , Animais , DNA/administração & dosagem , Feminino , Células HEK293 , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Injeções , Camundongos , Camundongos Endogâmicos BALB C , Polietilenoglicóis/química , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Sulfametazina/análogos & derivados , Temperatura , Uretana/análogos & derivados
15.
Biomacromolecules ; 19(6): 2062-2070, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29625005

RESUMO

In this work, pH-responsive polypeptide-based nanogels are reported as potential drug delivery systems. By the formation of pH-sensitive benzoic imine bonds, pH-responsive nanogels are constructed using hydrophilic methoxy poly(ethylene glycol)- b-poly[ N-[ N-(2-aminoethyl)-2-aminoethyl]-l-glutamate] (MPEG- b-PNLG) and hydrophobic terephthalaldehyde (TPA) as a cross-linker. At pH 7.4, MPEG- b-PNLG nanogels exhibit high stabilities with hydrophobic inner cores, which allow encapsulation of hydrophobic therapeutic agents. Under tumoral acidic environments (pH ∼6.4), the cleavage of benzoic imine bonds induces the destruction of MPEG- b-PNLG nanogels and leads to rapid release of their payloads. The formation and pH sensitivity of the nanogels are investigated by dynamic light scattering. These nanogels exhibit excellent stabilities in the presence of salt or against dilution. The globular morphologies of the nanogels are confirmed using transmission electron microscopy. Doxorubicin is used as a model drug to evaluate drug encapsulation and release. Finally, the anticancer activities of the drug-encapsulated nanogels are assessed in vitro.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/química , Polímeros/química , Materiais Biocompatíveis/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Reagentes de Ligações Cruzadas/química , Doxorrubicina/administração & dosagem , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Géis/química , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/administração & dosagem , Polietilenoglicóis/química
16.
Langmuir ; 33(37): 9324-9332, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28453943

RESUMO

The influence of hexamethylenetetraamine (HMTA) on the morphology of δ-MnO2 and its properties for electrical energy storage are investigated-specifically for ultrathick δ-MnO2 layers in the micron scale. Planar arrays of gold@δ-MnO2, core@shell nanowires, were prepared by electrodeposition with and without the HMTA and their electrochemical properties were evaluated. HMTA alters the MnO2 in three ways: First, it creates a more open morphology for the MnO2 coating, characterized by "petals" with a thickness of 6 to 9 nm, rather than much thinner δ-MnO2 sheets seen in the absence of HMTA. Second, the electronic conductivity of the δ-MnO2 is increased by an order of magnitude. Third, δ-MnO2 prepared in HMTA shows a (001) interlayer spacing that is expanded by ≈30% possibly accelerating Li transport. The net effect of "HTMA doping" is to dramatically improve high rate performance, culminating in an increase in the specific capacity for the thickest MnO2 shells examined here by a factor of 15 at 100 mV/s.

17.
J Appl Toxicol ; 37(9): 1046-1052, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28261823

RESUMO

The absorption of cadmium (Cd) may lead to Cd-related diseases such as renal tubular dysfunction and bone disease, and it is known to take around 10-30 years to reduce Cd concentrations to half their original levels. Urinary ß2 -microglobulin (ß2 -MG), N-acetyl-ß-D-glucosaminidase (NAG), protein, glucose and albumin were used as indicators of renal dysfunction caused by Cd exposure. Our previous study found that urinary Cd concentrations had increased recently and that age was more strongly associated with urinary ß2 -MG concentration than recent Cd body burden. Therefore, the purpose of the present study was to investigate the effect of aging on Cd concentrations and renal dysfunction. The Cd, ß2 -MG, NAG, protein, glucose and albumin concentrations in the urine of 40 Japanese subjects (20 females and 20 males) environmentally exposed to Cd were collected. They lived in the Kakehashi River basin and were divided into three age categories: 50-69, 70-79 and 80-99 years. Significant differences in urinary Cd and ß2 -MG concentrations were found among age groups, with urinary Cd levels tending to increase with age in both sexes. No significant correlations were found between urinary Cd and any indicators of renal dysfunction. The correlation between age, Cd and indicators of renal dysfunction was observed more clearly in females than in males. Age is more strongly correlated with indicators of renal dysfunction than Cd body burden. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Envelhecimento , Cádmio/toxicidade , Cádmio/urina , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/urina , Nefropatias/urina , Acetilglucosaminidase/urina , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/urina , Feminino , Humanos , Japão , Nefropatias/induzido quimicamente , Nefropatias/diagnóstico , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Microglobulina beta-2/urina
18.
Antimicrob Agents Chemother ; 60(12): 7449-7456, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27736769

RESUMO

Wastewater discharged from clinical isolation and general wards at two hospitals in Singapore was examined to determine the emerging trends of antibiotic resistance (AR). We quantified the concentrations of 12 antibiotic compounds by analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS), antibiotic-resistant bacteria (ARB), the class 1 integrase gene (intI1), and 16 antibiotic resistance genes (ARGs) that confer resistance to 10 different clinically relevant antibiotics. A subset of 119 antibiotic-resistant isolates were phylogenetically classified and tested for the presence of ARGs encoding resistance to ß-lactam antibiotics (blaNDM, blaKPC, blaSHV, blaCTX-M), amikacin [aac(6')-Ib], co-trimoxazole (sul1, sul2, dfrA), ciprofloxacin (qnrA, qnrB), and the intI1 gene. Among these resistant isolates, 80.7% were detected with intI1 and 66.4% were found to carry at least 1 of the tested ARGs. Among 3 sampled locations, the clinical isolation ward had the highest concentrations of ARB and the highest levels of ARGs linked to resistance to ß-lactam (blaKPC), co-trimoxazole (sul1, sul2, dfrA), amikacin [aac(6')-Ib], ciprofloxacin (qnrA), and intI1 We found strong positive correlations (P < 0.05) between concentrations of bacteria resistant to meropenem, ceftazidime, amikacin, co-trimoxazole, and ciprofloxacin and abundances of blaKPC, aac(6')-Ib, sul1, sul2, dfrA, qnrA, and intI1 genes.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Águas Residuárias/microbiologia , Amicacina/farmacologia , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Cromatografia Líquida , Ciprofloxacina/farmacologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/isolamento & purificação , Hospitais , Humanos , Integrases/genética , Integrases/isolamento & purificação , Singapura , Espectrometria de Massas em Tandem , Combinação Trimetoprima e Sulfametoxazol/farmacologia , beta-Lactamases/genética , beta-Lactamases/isolamento & purificação , beta-Lactamas/farmacologia
19.
J Nanosci Nanotechnol ; 16(1): 1090-4, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27398573

RESUMO

The immobilization efficiency, antimicrobial activity and recovery of lysosomal enzymes on NH2 functionalized magnetite nanoparticles have been studied under various conditions. The immobi- lization efficiency depends upon the ratio of the amount of enzyme and magnetite and it shows an increase with magnetite concentration which is due to the presence of amine group at the magnetite surface that leads to a strong attraction. The optimized reaction time to immobilize the lysosomal enzymes on magnetite was determined by using a rolling method. The immobilization efficiency increases with reaction time and reached a plateau after 5 minutes and then remained constant for 10 minutes. However, after 30 minutes the immobilization efficiency decreased to 85%, which is due to the weaker electrostatic interactions between magnetite and detached lysosomal enzymes. The recovery and stability of immobilized lysosomal enzymes has also been studied. The antimicrobial activity was almost 100% but it decreased upon reuse and no activity was observed after its reuse for seven times. The storage stability of lysosomal enzymes as an antimicrobial agent was about 88%, which decreased to 53% after one day and all activity of immobilized lysosomal enzymes was maintained after five days. Thus, the lysosomal enzymes immobilized on magnetite nanoparticles could potentially be used as antimicrobial agents to remove bacteria.


Assuntos
Anti-Infecciosos , Enzimas Imobilizadas , Escherichia coli/crescimento & desenvolvimento , Lisossomos/enzimologia , Nanopartículas de Magnetita/química , Saccharomyces cerevisiae/enzimologia , Dióxido de Silício , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Enzimas Imobilizadas/química , Enzimas Imobilizadas/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia
20.
Nano Lett ; 15(9): 5861-7, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26225457

RESUMO

We describe the preparation and properties of a coaxial, three-layer, gold-CdSe-gold nanowire 30 µm in length that functions as a monolithic photodetector. The gold (Au) electrode core of this sandwich structure is prepared using the lithographically patterned nanowire electrodeposition (LPNE) method on a glass surface. A CdSe shell of defined thickness, dCdSe, from 200 to 280 nm is then electrodeposited on this Au nanowire. Finally, a conformal gold layer is electrodeposited on top of the CdSe shell. The two concentric gold electrodes within this architecture measure the photoconductivity of the ultrathin CdSe absorbing layer in the direction orthogonal to the nanowire axis. This architecture enables accelerated response/recovery of the nanowire to light while simultaneously maximizing the photoconductive gain without relinquishing any of the photoresponsive area of a "bare" nanowire. Characterization by scanning electron microscopy (SEM) of focused ion beam (FIB) cross sections together with electron dispersive X-ray spectroscopy (EDS) reveal the distinct core-multishell nanostructure, layer thicknesses, and layer compositions. The position-dependent photoresponse along the axis of the nanowire, probed using a laser spot, shows that the Au nanoshell significantly enhances the photocurrent. The performance of Au-CdSe-Au core-multishell nanowire photodetectors depend sensitively on the thickness of CdSe nanoshell over the range of from 200 nm < dCdSe < 280 nm. The highest performance was obtained for the dCdSe = 250 nm this device, which showed a photoconductive gain of 2172, a responsivity of 209 A·W(-1), a response time of 17 µs, and a recovery time of 96 µs.

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