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1.
RSC Adv ; 14(4): 2341-2345, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38213964

RESUMO

Bis(3-indolyl)methanes (BIMs) are known for their important bioactivities, which include anti-cancer, anti-inflammatory, antibacterial, and antioxidant properties. In this study, we are disclosing a metal catalyst-free synthesis of BIMs in high yields via the alkylation reaction of indoles and alcohols in the presence of lithium tert-butoxide base. Notably, oxygen in air played an important role as an oxidant for the facilitation of this transformation. Interestingly, unactivated aliphatic alcohols could be successfully used as alkylating reagents in the alkylation reactions of indole. Especially, several chemical intermediates detected by GC-MS gave important information about the mechanism insights. This method demonstrated cost and environmental advantages for the development of green processes.

2.
Adv Sci (Weinh) ; 10(28): e2301493, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37559172

RESUMO

The metal-semiconductor heterojunction is imperative for the realization of electrically driven nanolasers for chip-level platforms. Progress in developing such nanolasers has hitherto rarely been realized, however, because of their complexity in heterojunction fabrication and the need to use noble metals that are incompatible with microelectronic manufacturing. Most plasmonic nanolasers lase either above a high threshold (101 -103 MW cm-2 ) or at a cryogenic temperature, and lasing is possible only after they are removed from the substrate to avoid the large ohmic loss and the low modal reflectivity, making monolithic fabrication impossible. Here, for the first time, record-low-threshold, room-temperature ultraviolet (UV) lasing of plasmon-coupled core-shell nanowires that are directly grown on silicon is demonstrated. The naturally formed core-shell metal-semiconductor heterostructure of the nanowires leads to a 100-fold improvement in growth density over previous results. This unprecedentedly high nanowire density creates intense plasmonic resonance, which is outcoupled to the resonant Fabry-Pérot microcavity. By boosting the emission strength by a factor of 100, the hybrid photonic-plasmonic system successfully facilitates a record-low laser threshold of 12 kW cm-2 with a spontaneous emission coupling factor as high as ≈0.32 in the 340-360 nm range. Such architecture is simple and cost-competitive for future UV sources in silicon integration.

3.
Bioresour Technol ; 369: 128380, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427768

RESUMO

Lignocellulosic and algal biomasses are known to be vital feedstocks to establish a green hydrogen supply chain toward achieving a carbon-neutral society. However, one of the most pressing issues to be addressed is the low digestibility of these biomasses in biorefinery processes, such as dark fermentation, to produce green hydrogen. To date, various pretreatment approaches, such as physical, chemical, and biological methods, have been examined to enhance feedstock digestibility. However, neither systematic reviews of pretreatment to promote biohydrogen production in dark fermentation nor economic feasibility analyses have been conducted. Thus, this study offers a comprehensive review of current biomass pretreatment methods to promote biohydrogen production in dark fermentation. In addition, this review has provided comparative analyses of the technological and economic feasibility of existing pretreatment techniques and discussed the prospects of the pretreatments from the standpoint of carbon neutrality and circular economy.


Assuntos
Hidrogênio , Lignina , Biomassa , Fermentação , Plantas , Biocombustíveis
5.
Vox Sang ; 117(12): 1384-1390, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36300858

RESUMO

BACKGROUND AND OBJECTIVES: The management of intraoperative blood loss in the surgical treatment of paediatric hip dysplasia is resource intensive. There are numerous clinical factors that impact the need for intraoperative transfusion. Identification of patient and surgical factors associated with increased blood loss may reduce the unnecessary use of resources. This study aimed to identify factors predictive of intraoperative transfusion in children undergoing hip dysplasia surgery. MATERIALS AND METHODS: This is a single-centre retrospective review of patients undergoing surgery for hip dysplasia from 1 January 2012 to 15 April 2021. Patient demographic factors, anaesthetic, surgical and transfusion histories were reviewed. Multivariable logistic regression analysis was performed to identify factors predictive of allogeneic red blood cell transfusion requirements during the intraoperative period. RESULTS: This study includes 595 patients who underwent open surgery for hip dysplasia, including 297 (52.6%) classified as developmental dysplasia (DD) and 268 (47.3%) as neuromuscular (NM) with a mean age of 9.1 years (interquartile range 3-14). Intraoperative allogeneic transfusion was identified in 26/297 (8.8%) DD and 73/268 (27.2%) NM patients. Adjusted factors associated with increased odds of intraoperative transfusion were NM (odds ratio [OR] = 2.96, 95% confidence interval [CI] [1.76, 5.00]) and the number of osteotomies performed (OR = 1.82/osteotomy, 95% CI [1.40, 2.35]). Adjusted factors that reduced the odds of transfusion were the use of antifibrinolytics (OR = 0.35, 95% CI [0.17, 0.71]) and regional anaesthesia (OR = 0.52, 95% CI [0.29, 0.94]). CONCLUSION: For children undergoing surgery for hip dysplasia, the number of osteotomies performed is predictive of the need for allogeneic blood transfusion. Antifibrinolytics and regional anaesthesia are associated with reduced risk for allogeneic blood transfusion. Blood management initiatives, such a preoperative optimization of haemoglobin and the use of antifibrinolytics, could target patients at increased risk of intraoperative bleeding and transfusion.


Assuntos
Antifibrinolíticos , Luxação do Quadril , Humanos , Criança , Luxação do Quadril/tratamento farmacológico , Luxação do Quadril/etiologia , Transfusão de Sangue , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Eritrócitos/efeitos adversos , Estudos Retrospectivos , Fatores de Risco
7.
Dermatol Online J ; 26(4)2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32621675

RESUMO

Dermatology is arguably the most competitive residency (81.6% match rate for United States allopathic seniors) with significantly more applicants than available positions. To objectify this process, the National Residency Match Program (NRMP) has produced bi-annual Charting Outcomes in Match (COM) datasets, which aggregate data from the prior two application cycles and tabulate statistics to aid applicants. In parallel, online forums provide medical trainees with vast amounts of information, including residency application insights. Reddit medical school subforum compiles annual spreadsheets of anonymous, individualized applicant data to aid future applicants. We compared this data to NRMP data to show that although the data means are similar (e.g. Step 1), the Reddit dermatology spreadsheet collects more data and the individualized nature aids applicants in a personalized way unlike the mean aggregate data in NRMP. Under univariate analysis, Alpha Omega Alpha status, overall publications, and dermatology-specific publications are associated with interview invitation rates. Although limitations of the study include small data size and reporting bias, this is the first of its kind to our knowledge to compare these two often-used tools to aid dermatology applicants. Future endeavors should expand anonymous data reporting and use the data to carry out more extensive studies to investigate factors influencing the application process.


Assuntos
Conjuntos de Dados como Assunto , Dermatologia/educação , Internato e Residência/estatística & dados numéricos , Seleção de Pessoal/estatística & dados numéricos , Escolha da Profissão , Entrevistas como Assunto/estatística & dados numéricos , Autorrelato , Estados Unidos
8.
Nanotechnology ; 31(34): 345401, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32365336

RESUMO

In this work, a feasible one-pot approach to synthesize manganese oxide/graphene composites, the so-called plasma-enhanced electrochemical exfoliation process (PE3P), has been developed. Herein, a composite of graphene decorated with manganese oxide nanoparticles was prepared via PE3P from a KMnO4 solution and graphite electrode under a voltage of 70 V in an ambient environment. By controlling the initial KMnO4 concentration, we obtained distinct MnO2/graphene samples. The prepared samples were characterized by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, and Raman spectroscopy. The electrochemical measurements of the MnO2/graphene composites revealed that the specific capacitance of the samples is approximately 320 F g-1 at a scan rate of 10 mV s-1, which is comparably very high for manganese oxide/carbon-based supercapacitor electrode materials. Considering the simple, low-cost, one-step and environmentally friendly preparation, our approach has the potential to be used for the fabrication of MnO2/graphene composites as the electrode materials of supercapacitors.

9.
Adv Healthc Mater ; 7(11): e1701381, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29663698

RESUMO

Dissolving microneedles (DMNs) have been widely studied in medical applications due to their pain-free administration, superior efficiency, and safe drug delivery. In skin vaccination, preserving the activity of the encapsulated antigen is an important consideration, as antigen activity is lost during DMN fabrication because of various stress factors. These stress factors vary between fabrication methods and each method affects the antigen's activity to different degrees. In this study, the activity of encapsulated antigens delivered by DMNs is compared between two recently developed DMN fabrication methods; droplet-born air blowing (DAB) and centrifugal lithography (CL) for a model scrub typhus vaccine antigen, ScaA. Although the in vitro analysis of ScaA-loaded DMNs (ScaA-DMNs) does not show any differences in physical properties depending on the fabrication methods, the immunogenicity of the CL-produced ScaA-DMN is significantly higher based on cytokine measurement and humoral immunity. DAB and CL differ in their solidification conditions, suggesting that solidification factors critically affect the encapsulated antigen's activity. ScaA-DMNs may also be stably stored for 4 weeks at room temperature. In conclusion, CL is a superior DMN fabrication method compared with DAB, and this study proves that DMN is feasible and practical for skin vaccination.


Assuntos
Antígenos de Bactérias/farmacologia , Agulhas , Vacinas Antirrickéttsia/farmacologia , Pele/imunologia , Vacinação/instrumentação , Vacinação/métodos , Animais , Antígenos de Bactérias/imunologia , Injeções Intradérmicas , Camundongos , Vacinas Antirrickéttsia/imunologia , Suínos
10.
PLoS One ; 11(5): e0156638, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27232754

RESUMO

Sorghum vegetative tissues are becoming increasingly important for biofuel production. The composition of sorghum stem tissues is influenced by genotype, environment and photoperiod sensitivity, and varies widely between varieties and also between different stem tissues (outer rind vs inner pith). Here, the amount of cellulose, (1,3;1,4)-ß-glucan, arabinose and xylose in the stems of twelve diverse sorghum varieties, including four photoperiod-sensitive varieties, was measured. At maturity, most photoperiod-insensitive lines had 1% w/w (1,3;1,4)-ß-glucan in stem pith tissue whilst photoperiod-sensitive varieties remained in a vegetative stage and accumulated up to 6% w/w (1,3;1,4)-ß-glucan in the same tissue. Three sorghum lines were chosen for further study: a cultivated grain variety (Sorghum bicolor BTx623), a sweet variety (S. bicolor Rio) and a photoperiod-sensitive wild line (S. bicolor ssp. verticilliflorum Arun). The Arun line accumulated 5.5% w/w (1,3;1,4)-ß-glucan and had higher SbCslF6 and SbCslH3 transcript levels in pith tissues than did photoperiod-insensitive varieties Rio and BTx623 (<1% w/w pith (1,3;1,4)-ß-glucan). To assess the digestibility of the three varieties, stem tissue was treated with either hydrolytic enzymes or dilute acid and the release of fermentable glucose was determined. Despite having the highest lignin content, Arun yielded significantly more glucose than the other varieties, and theoretical calculation of ethanol yields was 10 344 L ha-1 from this sorghum stem tissue. These data indicate that sorghum stem (1,3;1,4)-ß-glucan content may have a significant effect on digestibility and bioethanol yields. This information opens new avenues of research to generate sorghum lines optimised for biofuel production.


Assuntos
Biocombustíveis , Caules de Planta/metabolismo , Sorghum/metabolismo , Biomassa , Carbono/metabolismo , Parede Celular/metabolismo , Etanol/química , Genótipo , Glucose/metabolismo , Caules de Planta/citologia , Sorghum/citologia , Sorghum/genética , Amido/metabolismo
11.
J Matern Fetal Neonatal Med ; 29(7): 1083-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25897637

RESUMO

OBJECTIVE: To identify characteristics of pregnant women potentially influencing the decision to participate in peripartum interventional research. METHODS: Women screened as eligible to participate in two prospective interventional trials conducted in the labor and delivery unit at a single center were included. Characteristics of eligible women were compared based on their decision whether to participate or not. The best predictors of research participation were identified using multivariable logistic regression analyses. RESULTS: Of the 605 subjects who screened as eligible to participate, 363 (60%) agreed to participate and 242 (40%) declined. Women using a private obstetric provider or who had prior obstetrical complications were less likely to participate [aOR 0.6 (95% CI: 0.4-0.8)] and [aOR 0.6 (95% CI: 0.4-0.9)], respectively. A history of a mental health condition and a higher body mass index (BMI) were marginally more likely to participate [aOR 1.5 (95% CI: 1.0-2.3)] and [aOR 1.03 (95% CI: 1.0-1.1)], respectively. Overall logistic regression model R(2) was 0.23. CONCLUSIONS: There are differences between eligible subjects who decide to participate or not participate in prospective peripartum interventional research. There is a need to better understand non-participation in order to improve recruitment of representative populations that allow more generalizable research results.


Assuntos
Pesquisa Biomédica , Participação do Paciente , Seleção de Pacientes , Período Periparto , Gestantes , Adulto , Tomada de Decisões , Feminino , Humanos , Trabalho de Parto , Paridade , Participação do Paciente/psicologia , Participação do Paciente/estatística & dados numéricos , Gravidez , Gestantes/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Adulto Jovem
12.
J Biol Chem ; 281(48): 37183-94, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17001080

RESUMO

Mammalian cell-derived West Nile virus preferentially infects cells expressing the C-type lectin CD209L (dendritic cellspecific ICAM-3 grabbing nonintegrin-related protein; liver- and lymph node-specific ICAM-3 grabbing nonintegrin) but not cells expressing CD209 (dendritic cell-specific ICAM-3 grabbing nonintegrin). In contrast, Dengue virus infection is enhanced in cells expressing either attachment factor. The West Nile virus envelope (E) protein contains a single N-linked glycosylation site at residue 154, whereas Dengue virus E contains sites at residues 153 and 67. We introduced a glycosylation site at position 67 into West Nile virus E. Reporter virus particles pseudotyped with this E protein infected cells using either CD209 or CD209L. We also introduced glycosylation sites at several novel positions. All sites allowed CD209L-mediated infection, but only a subset promoted CD209 use. As seen for other viruses, mannose-rich glycans on West Nile virus were required for its interactions with CD209. Surprisingly, however, mannose-rich glycans were not required for CD209L-mediated infection. Complex glycans, particularly N-acetylglucosamine-terminated structures, were able to mediate reporter virus particle interactions with CD209L. We propose that CD209L recognizes glycosylated flaviviruses with broad specificity, whereas CD209 is selective for flaviviruses bearing mannose-rich glycans. The location of the N-linked glycosylation sites on a virion determines the types of glycans incorporated, thus controlling viral tropism for CD209-expressing cells.


Assuntos
Asparagina/química , Moléculas de Adesão Celular/fisiologia , Lectinas Tipo C/fisiologia , Polissacarídeos/química , Receptores de Superfície Celular/fisiologia , Vírus do Nilo Ocidental/metabolismo , Sítios de Ligação , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/química , Vírus da Dengue/metabolismo , Flavivirus/metabolismo , Genes Reporter , Glicosilação , Humanos , Integrinas/metabolismo , Células K562 , Lectinas/química , Lectinas Tipo C/biossíntese , Lectinas Tipo C/química , Modelos Moleculares , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/química
13.
J Virol ; 80(3): 1290-301, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16415006

RESUMO

The C-type lectins DC-SIGN and DC-SIGNR bind mannose-rich glycans with high affinity. In vitro, cells expressing these attachment factors efficiently capture, and are infected by, a diverse array of appropriately glycosylated pathogens, including dengue virus. In this study, we investigated whether these lectins could enhance cellular infection by West Nile virus (WNV), a mosquito-borne flavivirus related to dengue virus. We discovered that DC-SIGNR promoted WNV infection much more efficiently than did DC-SIGN, particularly when the virus was grown in human cell types. The presence of a single N-linked glycosylation site on either the prM or E glycoprotein of WNV was sufficient to allow DC-SIGNR-mediated infection, demonstrating that uncleaved prM protein present on a flavivirus virion can influence viral tropism under certain circumstances. Preferential utilization of DC-SIGNR was a specific property conferred by the WNV envelope glycoproteins. Chimeras between DC-SIGN and DC-SIGNR demonstrated that the ability of DC-SIGNR to promote WNV infection maps to its carbohydrate recognition domain. WNV virions and subviral particles bound to DC-SIGNR with much greater affinity than DC-SIGN. We believe this is the first report of a pathogen interacting more efficiently with DC-SIGNR than with DC-SIGN. Our results should lead to the discovery of new mechanisms by which these well-studied lectins discriminate among ligands.


Assuntos
Moléculas de Adesão Celular/fisiologia , Lectinas Tipo C/fisiologia , Receptores de Superfície Celular/fisiologia , Vírus do Nilo Ocidental/fisiologia , Vírus do Nilo Ocidental/patogenicidade , Animais , Sítios de Ligação , Adesão Celular , Moléculas de Adesão Celular/genética , Linhagem Celular , Cricetinae , Glicosilação , Células HeLa , Humanos , Lectinas Tipo C/genética , Ligantes , Mutação , Receptores de Superfície Celular/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/fisiologia , Virulência , Vírus do Nilo Ocidental/genética
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