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1.
Langmuir ; 40(4): 2183-2190, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38236758

RESUMO

Versatile nanostructures of conducting polymers are highly relevant based on unique properties, including electrical, optical, and thermal, with changes in morphology. This contribution reports a facile and reproducible synthesis approach for the design of conducting polymer nanostructures from zero- to three-dimensional composites. Two polymerization steps, namely, self-assembly-directed and interface thin layer-templated polymerizations in this synthesis, were kinetically controlled to fabricate such nanostructures directly. The uniquely designed bicontinuous nanoreactor offers an easy synthesis technique for fabricating 3D multifunctional conducting polymer composites. Self-assembly-directed polymerization could be controlled to form nanorods and further directed to form nanobowl/hollow spherical structures. The interface thin layer template process was tuned to produce hollow spherical and 2D film nanostructures. Kinetic control of polymerization was able to provide access to unprecedented nanostructures of the conducting polymers ranging from DNA origami to gecko-inspired nanostructures, with potential applications in drug delivery, energy storage, and adhesive materials. For example, this is the first conducting polymer material that can demonstrate similar adhesiveness (around 8 N/cm2) to gecko finger hairs.

2.
Brain Inj ; 38(1): 7-11, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38117178

RESUMO

OBJECTIVE: With mobile health technologies serving as an alternative means of providing healthcare, evaluating patients' abilities to navigate digital infrastructures is becoming increasingly relevant. The goal of this study is to investigate smartphone use patterns among individuals with history of moderate-to-severe traumatic brain injury (TBI). METHODS: An anonymous survey was delivered via e-mail or text message to eligible participants who had a history of moderate-to-severe TBI and were prospectively followed at one of the eight participating Traumatic Brain Injury Model Systems centers for at least 1-year post-injury. The survey captured demographic data and included a questionnaire to evaluate smartphone use (calling, texting, web browsing, etc.). RESULTS: A total of 2665 eligible individuals were contacted to complete the survey, 472 of which responded. 441 of them reported smartphone use. Individuals ages 45 and older were significantly less likely to use their phones for functions other than calling and texting when compared to individuals ages 18-44 (p < 0.05). CONCLUSIONS: Most individuals with moderate-to-severe TBI in this cohort demonstrated intentional smartphone use, suggesting that mobile health technologies may be feasible as a cost-effective healthcare alternative. However, doing so will require additional interventions to provide further technological education especially in older individuals with TBI.


Assuntos
Lesões Encefálicas Traumáticas , Envio de Mensagens de Texto , Humanos , Idoso , Smartphone , Lesões Encefálicas Traumáticas/epidemiologia
3.
Chem Biodivers ; 21(6): e202400379, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38743034

RESUMO

Robusta coffee blossom honey stands as a key regional product in Dak Lak province, Vietnam. Despite its significance, there exists a dearth of scientific data for assessing its quality. This study aims to fill this gap by characterizing the physicochemical properties and biological activities of coffee blossom honeys from three distinct sub-regions within Dak Lak province, Vietnam. These activities include ferric reducing power (FRP), DPPH and ABTS radical scavenging, as well as tyrosinase inhibitory activities. Moreover, the study compares these honey samples with other popular varieties in Vietnam, such as Lychee and Longan honeys. The physicochemical parameters of the honey samples meet the standards set by Codex Alimentarius 2001. Through UPLC analysis, eleven compounds were identified, with caffeine serving as a marker for coffee honey. Furthermore, by employing multiple factor analysis (MFA), it was observed that certain physicochemical properties correlate positively with tyrosinase inhibitory, DPPH, ABTS free radicals scavenging activities, and FRP. Notably, tyrosinase inhibitory activity exhibited a positive correlation with antioxidant activity. These findings underscore the high quality of Coffea robusta honey, showcasing its potent antioxidant and tyrosinase inhibitory activities.


Assuntos
Antioxidantes , Inibidores Enzimáticos , Mel , Monofenol Mono-Oxigenase , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Benzotiazóis/química , Compostos de Bifenilo/antagonistas & inibidores , Café/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Flores/química , Mel/análise , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Picratos/antagonistas & inibidores , Ácidos Sulfônicos/antagonistas & inibidores , Vietnã
4.
Sensors (Basel) ; 24(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38544254

RESUMO

The accuracy and efficacy of medical treatment would be greatly improved by the continuous and real-time monitoring of protein biomarkers. Identification of cancer biomarkers in patients with solid malignant tumors is receiving increasing attention. Existing techniques for detecting cancer proteins, such as the enzyme-linked immunosorbent assay, require a lot of work, are not multiplexed, and only allow for single-time point observations. In order to get one step closer to clinical usage, a dynamic platform for biosensing the cancer biomarker CD44 using a single-mode optical fiber-based ball resonator biosensor was designed, constructed and evaluated in this work. The main novelty of the work is an in-depth study of the capability of an in-house fabricated optical fiber biosensor for in situ detection of a cancer biomarker (CD44 protein) by conducting several types of experiments. The main results of the work are as follows: (1) Calibration of the fabricated fiber-optic ball resonator sensors in both static and dynamic conditions showed similar sensitivity to the refractive index change demonstrating its usefulness as a biosensing platform for dynamic measurements; (2) The fabricated sensors were shown to be insensitive to pressure changes further confirming their utility as an in situ sensor; (3) The sensor's packaging and placement were optimized to create a better environment for the fabricated ball resonator's performance in blood-mimicking environment; (4) Incubating increasing protein concentrations with antibody-functionalized sensor resulted in nearly instantaneous signal change indicating a femtomolar detection limit in a dynamic range from 7.1 aM to 16.7 nM; (5) The consistency of the obtained signal change was confirmed by repeatability studies; (6) Specificity experiments conducted under dynamic conditions demonstrated that the biosensors are highly selective to the targeted protein; (7) Surface morphology studies by AFM measurements further confirm the biosensor's exceptional sensitivity by revealing a considerable shift in height but no change in surface roughness after detection. The biosensor's ability to analyze clinically relevant proteins in real time with high sensitivity offers an advancement in the detection and monitoring of malignant tumors, hence improving patient diagnosis and health status surveillance.


Assuntos
Técnicas Biossensoriais , Neoplasias , Humanos , Biomarcadores Tumorais , Técnicas Biossensoriais/métodos , Tecnologia de Fibra Óptica/métodos , Fibras Ópticas , Proteínas , Neoplasias/diagnóstico , Receptores de Hialuronatos
5.
J Biol Chem ; 298(6): 101981, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35472332

RESUMO

Mesenchymal stem cells (MSCs) are adult stem cell populations and exhibit great potential in regenerative medicine and oncology. Platelet-derived growth factors (PDGFs) are well known to regulate MSC biology through their chemotactic and mitogenic properties. However, their direct roles in the regulation of MSC lineage commitment are unclear. Here, we show that PDGF D promotes the differentiation of human bone marrow mesenchymal stem cells (hBMSCs) into osteoblasts and inhibits hBMSC differentiation into adipocytes. We demonstrate that PDGF D-induced ß-actin expression and polymerization are essential for mediating this differential regulation of osteoblastogenesis and adipogenesis. Interestingly, we found that PDGF D induces massive upward molecular weight shifts of its cognate receptor, PDGF receptor beta (ß-PDGFR) in hBMSCs, which was not observed in fibroblasts. Proteomic analysis indicated that the E3 ubiquitin ligase HECT, UBA, and WWE domain-containing protein 1 (HUWE1) associates with the PDGF D-activated ß-PDGFR signaling complex in hBMSCs, resulting in ß-PDGFR polyubiquitination. In contrast to the well-known role of ubiquitin in protein degradation, we provide evidence that HUWE1-mediated ß-PDGFR polyubiquitination delays ß-PDGFR internalization and degradation, thereby prolonging AKT signaling. Finally, we demonstrate that HUWE1-regulated ß-PDGFR signaling is essential for osteoblastic differentiation of hBMSCs, while being dispensable for PDGF D-induced hBMSC migration and proliferation as well as PDGF D-mediated inhibition of hBMSC differentiation into adipocytes. Taken together, our findings provide novel insights into the molecular mechanism by which PDGF D regulates the commitment of hBMSCs into the osteoblastic lineage.


Assuntos
Linfocinas/metabolismo , Células-Tronco Mesenquimais , Fator de Crescimento Derivado de Plaquetas/metabolismo , Ubiquitina-Proteína Ligases , Diferenciação Celular , Proliferação de Células , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Proteômica , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
6.
PLoS Biol ; 18(8): e3000762, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760088

RESUMO

Centrosomes, the main microtubule organizing centers (MTOCs) of metazoan cells, contain an older "mother" and a younger "daughter" centriole. Stem cells either inherit the mother or daughter-centriole-containing centrosome, providing a possible mechanism for biased delivery of cell fate determinants. However, the mechanisms regulating centrosome asymmetry and biased centrosome segregation are unclear. Using 3D-structured illumination microscopy (3D-SIM) and live-cell imaging, we show in fly neural stem cells (neuroblasts) that the mitotic kinase Polo and its centriolar protein substrate Centrobin (Cnb) accumulate on the daughter centriole during mitosis, thereby generating molecularly distinct mother and daughter centrioles before interphase. Cnb's asymmetric localization, potentially involving a direct relocalization mechanism, is regulated by Polo-mediated phosphorylation, whereas Polo's daughter centriole enrichment requires both Wdr62 and Cnb. Based on optogenetic protein mislocalization experiments, we propose that the establishment of centriole asymmetry in mitosis primes biased interphase MTOC activity, necessary for correct spindle orientation.


Assuntos
Proteínas de Ciclo Celular/genética , Centríolos/metabolismo , Centrossomo/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Mitose , Proteínas Serina-Treonina Quinases/genética , Animais , Animais Geneticamente Modificados , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Ciclo Celular/metabolismo , Centríolos/ultraestrutura , Centrossomo/ultraestrutura , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Interfase , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Optogenética/métodos , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Proteína Vermelha Fluorescente
7.
Brain Inj ; 36(3): 359-367, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35377820

RESUMO

OBJECTIVE: To examine the usability of an Apple Watch-based, two-way Personalized Mobile Trainer (PMT) in community-based exercise programs for individuals with chronic traumatic brain injury (cTBI). METHODS: This is a prospective pilot study. Twenty participants with cTBI aged 46-73 were enrolled in a 3-month individualized exercise program. After one in-person training session on PMT and exercise program, participants were prescribed either aerobic exercise training (AET) or stretching and toning (SAT) performed at home. The PMT was used to remotely deliver updated exercise prescription, track exercise progress, and communicate with the participants. The primary outcome was compliance with the exercise programs. RESULTS: All the participants completed the assigned exercise program with an average compliance of 76%. Nineteen (95%) participants were able to use the PMT properly during exercise sessions. After 3 months of training, the AET trended toward maintaining exercise endurance when compared with the SAT group (0.3% vs -4%, p = 0.14) with a medium effect size of 0.43. CONCLUSION: Using the PMT system to support and track exercise in community-based exercise programs is feasible. The PMT may promote compliance with the training program but testing its effectiveness with larger trials is warranted.


Assuntos
Lesões Encefálicas Traumáticas , Adulto , Humanos , Exercício Físico , Terapia por Exercício , Projetos Piloto , Estudos Prospectivos
8.
J Occup Rehabil ; 32(3): 464-472, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35037157

RESUMO

Purpose The COVID-19 pandemic has disproportionately affected the lives of people with disabilities (PWD). How the pandemic affects the employment of PWD and employers has yet to be determined. We aimed to investigate the employment consequences of the pandemic as experienced by PWD and employers. The research questions were: (1) What employment effects do PWD experience, and what business changes do employers encounter as a result of the COVID-19 pandemic? (2) What challenges have PWD encountered during the pandemic? Methods Cross-sectional online surveys of 733 PWD and 67 employers in the Midwestern United States. Results Compared to non-disabled peers, PWD encountered more challenges in employment during the pandemic. We found high percentages of both employers and PWD experiencing employment changes and business shutdown during the pandemic. For PWD whose employment was not affected, 14.6% of the participants (n = 107) expected a loss of income and worried about the economic uncertainty of the pandemic. Unemployment for PWD is high due to illness or disability, being laid-off or furloughed, business reductions, and not feeling safe to work. However, only about 18.6% of unemployed PWD (n = 16) received pay or benefits for the time they were not working even though more than half filed for unemployment benefits. Conclusions The pandemic adversely affected employment of PWD as reported by workers and employers. Findings parallel the experience of the non-disabled workforce, but reveal vulnerabilities that reflect disability consequences and the need for job accommodations. Results reveal emergent needs for policy supports to reduce the disparities experienced by PWD in the workplace.


Assuntos
COVID-19 , Pessoas com Deficiência , COVID-19/epidemiologia , Estudos Transversais , Emprego , Humanos , Pandemias , Local de Trabalho
9.
Int J Med Sci ; 17(13): 2031-2039, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32788882

RESUMO

The PB2 protein of the influenza virus RNA polymerase is a major virulence determinant of influenza viruses. It binds to the cap structure at the 5' end of host mRNA to generate short capped RNA fragments that are used as primers for viral transcription named cap-snatching. A large number of the compounds were shown to bind the minimal cap-binding domain of PB2 to inhibit the cap-snatching machinery. However, their binding in the context of an extended form of the PB2 protein has remained elusive. A previous study reported some promising compounds including azaindole and hydroxymethyl azaindole, which were analyzed here to predict binding affinity to PB2 protein using the steered molecular dynamics (SMD) and molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) methods. The results show that the rupture force (Fmax) value of three complexes is in agreement with the binding free energy value (ΔGbind) estimated by the MM-PBSA method, whereas for the non-equilibrium pulling work (Wpull) value a small difference between A_PB2-4 and A_PB2-12 was observed. The binding affinity results indicate the A_PB2-12 complex is more favorable than the A_PB2-4 and A_PB2-16 complexes, which means the inhibitor (12) has the potential to be further developed as anti-influenza agents in the treatment of influenza A.


Assuntos
Antivirais/metabolismo , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Virais/química , Proteínas Virais/metabolismo , Antivirais/química , Ligação de Hidrogênio , Simulação de Dinâmica Molecular
10.
Biochem Biophys Res Commun ; 495(1): 1240-1248, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29170133

RESUMO

The mitochondrial Bit1 protein exerts tumor-suppressive function in NSCLC through induction of anoikis and inhibition of EMT. Having this dual tumor suppressive effect, its downregulation in the established human lung adenocarcinoma A549 cell line resulted in potentiation of tumorigenicity and metastasis in vivo. However, the exact role of Bit1 in regulating malignant growth and transformation of human lung epithelial cells, which are origin of most forms of human lung cancers, has not been examined. To this end, we have downregulated the endogenous Bit1 expression in the immortalized non-tumorigenic human bronchial epithelial BEAS-2B cells. Knockdown of Bit1 enhanced the growth and anoikis insensitivity of BEAS-2B cells. In line with their acquired anoikis resistance, the Bit1 knockdown BEAS-2B cells exhibited enhanced anchorage-independent growth in vitro but failed to form tumors in vivo. The loss of Bit1-induced transformed phenotypes was in part attributable to the repression of E-cadherin expression since forced exogenous E-cadherin expression attenuated the malignant phenotypes of the Bit1 knockdown cells. Importantly, we show that the loss of Bit1 expression in BEAS-2B cells resulted in increased Erk activation, which functions upstream to promote TLE1-mediated transcriptional repression of E-cadherin. These collective findings indicate that loss of Bit1 expression contributes to the acquisition of malignant phenotype of human lung epithelial cells via Erk activation-induced suppression of E-cadherin expression.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/fisiologia , Anoikis/fisiologia , Caderinas/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Transformação Celular Neoplásica/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas Mitocondriais/metabolismo , Células Epiteliais Alveolares/citologia , Antígenos CD , Diferenciação Celular/fisiologia , Linhagem Celular , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/patologia , Regulação para Baixo/fisiologia , Humanos
11.
Perfusion ; 33(2): 115-122, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28823216

RESUMO

BACKGROUND: New onset of heart failure (HF) is an indication for the assessment of coronary artery disease. The aim of this study was to clarify the mechanistic causes of new onset HF associated with ischemic electrocardiograph (EKG) changes and chest pain in patients with patent or minimally diseased coronary arteries. METHODS: Twenty consecutive patients (Group A) were retrospectively reviewed if they had an history of new onset of HF, chest pain, electrocardiographic changes indicating ischemia (ST depression or T wave inversion in at least two consecutive leads and a negative coronary angiogram [CA]) and did not require percutaneous coronary intervention or coronary artery bypass grafting. A 1:1 matched cohort (Group B) was adopted to validate the results. RESULTS: All patients had a negative CA. The majority of subjects in Group A had a higher left ventricular end diastolic pressure (LVEDP) when compared to the control group (p<0.05). Similarly, the aortic diastolic (AOD) pressure was lower in Group A than in Group B (p<0.05). In patients with elevated LVEDP and low AOD, with a coronary perfusion pressure (CPP) <20 mmHg, deep T wave inversion in two consecutive leads were more frequently observed. When the CPP was between 20-30 mmHg, a mild ST depression were more frequently recorded (p<0.05). Conversely, when the CPP was >30 mmHg, only mild non-specific ST-T changes or normal EKG were observed. CONCLUSIONS: In patients with HF and EKG changes suggestive of ischemia in at least two consecutive leads, a lower AOD could aggravate ischemia in patients with elevated left ventricular end diastolic pressure.


Assuntos
Angiografia Coronária/métodos , Doença das Coronárias/complicações , Eletrocardiografia/métodos , Insuficiência Cardíaca/fisiopatologia , Isquemia/fisiopatologia , Idoso , Doença das Coronárias/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Disfunção Ventricular Esquerda/fisiopatologia
12.
Biochem Biophys Res Commun ; 455(3-4): 277-84, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25446087

RESUMO

The Groucho transcriptional corepressor TLE1 protein has recently been shown to be a putative lung specific oncogene, but its underlying oncogenic activity in lung cancer has not been fully elucidated. In this report, we investigated whether TLE1 regulates lung cancer aggressiveness using the human lung adenocarcinoma cell line A549 as a model system. Through a combination of genetic approaches, we found that TLE1 potentiates epithelial-to-mesenchymal transition (EMT) in A549 cells in part through suppression of the tumor suppressor gene E-cadherin. Exogenous expression of TLE1 in A549 cells resulted in heightened EMT phenotypes (enhanced fibroblastoid morphology and increased cell migratory potential) and in molecular alterations characteristic of EMT (downregulation of the epithelial marker E-cadherin and upregulation of the mesenchymal marker Vimentin). Conversely, downregulation of endogenous TLE1 expression in these cells resulted in reversal of basal EMT characterized by a cuboidal-like epithelial cell phenotype, reduced cell motility, and upregulated E-cadherin expression. Mechanistic studies showed that TLE1 suppresses E-cadherin expression at the transcriptional level in part by recruiting histone deacetylase (HDAC) activity to the E-cadherin promoter. Consistently, the HDAC inhibitor TSA partially reversed the TLE1-induced E-cadherin downregulation and cell migration, suggesting a role for HDACs in TLE1-mediated transcriptional repression of E-cadherin and EMT function. These findings uncover a novel role of TLE1 in regulating EMT in A549 cells through its repressive effect on E-cadherin and provide a mechanism for TLE1 oncogenic activity in lung cancer.


Assuntos
Adenocarcinoma/metabolismo , Caderinas/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/metabolismo , Proteínas Repressoras/fisiologia , Adenocarcinoma de Pulmão , Anoikis , Antígenos CD , Hidrolases de Éster Carboxílico/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteínas Correpressoras , Regulação para Baixo , Transição Epitelial-Mesenquimal , Histona Desacetilases/metabolismo , Humanos , Proteínas Mitocondriais/metabolismo , Metástase Neoplásica , Regiões Promotoras Genéticas , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/metabolismo , Transcrição Gênica
13.
iScience ; 27(5): 109637, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38646165

RESUMO

Carcinoembryonic antigen (CEA) is a critical biomarker for identifying colon cancer. This work presents an electrochemical impedance spectroscopy (EIS) based aptasensor for detecting CEA, utilizing a single-stranded DNA (ssDNA) aptamer previously selected and characterized by our research group. The surface of an interdigitated gold electrode (IDE) was successfully functionalized with an 18-HEG-modified aptamer sequence. The developed aptasensor demonstrated high specificity and sensitivity with detection limits of 2.4 pg/mL and 3.8 pg/mL for CEA in buffer and human serum samples, respectively. The optimal incubation time for the target protein was 20 min, and EIS measurements took less than 3 min. Atomic force microscopy (AFM) micrographs supported the EIS data, demonstrating a change in IDE surface roughness after each modification step, confirming the successful capture of the target. The potential of this developed EIS aptasensor in detecting CEA in complex samples holds promise.

14.
Biomed Opt Express ; 15(1): 185-198, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38223184

RESUMO

Detection of biomarkers for tracking disease progression is becoming increasingly important in biomedicine. Using saliva as a diagnostic sample appears to be a safe, cost-effective, and non-invasive approach. Salivary interleukin-8 levels demonstrate specific changes associated with diseases such as obstructive pulmonary disease, squamous cell carcinoma, oral cancer, and breast cancer. Traditional protein detection methods, such as enzyme-linked immunosorbent assay (ELISA), mass spectrometry, and Western blot are often expensive, complex, and time-consuming. In this study, an optical fiber-based biosensor was developed to detect salivary IL-8 protein in a label-free manner. The biosensor was able to achieve an ultra-low limit detection of 0.91 fM. Moreover, the tested concentration range was wide: from 273 aM to 59 fM. As a proof-of-concept for detecting the protein in real clinical samples, the detection was carried out in artificial saliva. It was possible to achieve high sensitivity for the target protein and minimal signal alterations for the control proteins.

15.
Lab Chip ; 24(2): 224-233, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38053518

RESUMO

Here, we report a fluorescent electrospun nanofiber membrane for integration into microfluidic devices towards lung-on-a-chip applications complemented with the results of computational fluid dynamics modelling. A proposed hybrid poly(ε-caprolactone) (PCL)-collagen membrane was developed, characterized, tested, and integrated into a prototype microfluidic chip for biocompatibility studies. The resulting membrane has a thickness of approximately 10 µm, can be adjusted for appropriate porosity, and offers excellent biocompatibility for mimicry of a basement membrane to be used in lung-on-a-chip device applications. Several membrane variations were synthesized and evaluated using SEM, FTIR, AFM, and high-resolution confocal fluorescence microscopy. A sample microfluidic chip made of cyclic olefin copolymer and polydimethylsiloxane was built and integrated with the developed PCL-collagen membrane for on-chip cell culture visualisation and biocompatibility studies. The sample chip design was modelled to determine the optimal fluidic conditions for using the membrane in the chip under fluidic conditions for future studies. The integration of the proposed membrane into microfluidic devices represents a novel strategy for improving lung-on-a-chip applications which can enhance laboratory recapitulation of the lung microenvironment.


Assuntos
Microfluídica , Nanofibras , Pulmão , Colágeno , Dispositivos Lab-On-A-Chip
16.
J Inorg Biochem ; 258: 112619, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38823066

RESUMO

The present study describes a novel antimicrobial mechanism based on Sodium Orthovanadate (SOV), an alkaline phosphatase inhibitor. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were employed to examine the surface morphologies of the test organism, Escherichia coli (E. coli), during various antibacterial phases. Our results indicated that SOV kills bacteria by attacking cell wall growth and development, leaving E. coli's outer membrane intact. Our antimicrobial test indicated that the MIC of SOV for both E. coli and Lactococcus lactis (L. lactis) is 40 µM. A combination of quantum mechanical calculations and vibrational spectroscopy revealed that divanadate from SOV strongly coordinates with Ca2+ and Mg2+, which are the activity centers for the phosphatase that regulates bacterial cell wall synthesis. The current study is the first to propose the antibacterial mechanism caused by SOV attacking cell wall.


Assuntos
Antibacterianos , Escherichia coli , Vanadatos , Vanadatos/química , Vanadatos/farmacologia , Escherichia coli/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Lactococcus lactis , Testes de Sensibilidade Microbiana , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Parede Celular/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/antagonistas & inibidores
17.
Environ Sci Pollut Res Int ; 31(3): 4640-4653, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38105328

RESUMO

Water contamination by organic pollutants is a serious environmental problem. 4-Nitrophenol (4-NP) is a potentially harmful chemical, which is commonly present in industrial effluents and can severely damage human health. Photocatalytic reduction of hazardous 4-NP by nano-sized materials to produce 4-aminophenol (4-AP), which is a commercially valuable product, is a promising alternative as the process is framed within the circular economy. In this context, Ag-doped TiO2 (AT) catalysts were synthesized by liquid impregnation and reduction techniques, and their structure, morphology, elemental composition, textural, and light absorption properties were evaluated by XRD, Raman spectroscopy, SEM, TEM, EDS, BET, and DRS spectroscopy. AT catalysts exhibited an enhanced photocatalytic reduction of 4-NP into 4-aminophenol (4-AP) in the presence of NaBH4. Among the tested catalysts, AT21 prepared by a simple aqueous reduction method showed the highest activity reaching about 98% 4-NP reduction within 10 min. Antibacterial tests of these catalysts against Bacillus subtilis, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa revealed that AT21 also exhibited the lowest minimum inhibitory concentration, suggesting that it has the strongest antibacterial activity. These findings suggest that AT21 catalyst with improved catalytic and antibacterial properties can potentially be utilized for the remediation of 4-NP-contaminated water environment.


Assuntos
Aminofenóis , Antibacterianos , Nitrofenóis , Análise Espectral Raman , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Água , Catálise
18.
Microb Biotechnol ; 17(3): e14426, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38497275

RESUMO

Fluctuations in redox conditions in bioprocesses can alter the end-products, reduce their concentration, and lengthen the process time. Electrofermentation enables rapid metabolic modulation of biosynthesis and allows control of redox imbalances in biofilm-based fermentation processes. In this study, electrofermentation is used to boost the production of the bacterial biopolymer poly-γ-glutamic acid (γ-PGA) from Bacillus subtilis ATCC 6051. When compared to control experiments (3.3 ± 0.99 g L-1 ), the application of an electrode potential E = 0.4 V versus Ag/AgCl results in a more than two-fold increase in the production of γ-PGA (9.13 ± 1.4 g L-1 ). Using an engineered B. subtilis strain, in which γ-PGA production is driven by isopropyl ß-d-1-thiogalactopyranoside, electrofermentation improves polymer concentrations from 15.4 ± 1.5 to 23.1 ± 1.6 versus g L-1 . These results confirm that electrofermentation conditions can be adopted to increase the concentration of γ-PGA and perhaps other extracellular biopolymers in industrial strains.


Assuntos
Bacillus subtilis , Ácido Glutâmico , Ácido Poliglutâmico/análogos & derivados , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Ácido Glutâmico/metabolismo , Fermentação , Biofilmes
19.
NeuroRehabilitation ; 54(3): 373-381, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38457158

RESUMO

BACKGROUND: Individuals with moderate to severe traumatic brain injury (msTBI) have reported a lack of motivation, lack of time, and fatigue as perceived barriers to exercise. OBJECTIVE: To evaluate the effects of an exercise program on self-reported health-related symptoms and quality of life in persons 45-years and older with msTBI. METHODS: Post-hoc analysis of a prospective community-based 12-week exercise program of 20 adults, age 45-80 years, with msTBI. Ten were in aerobic exercise training (AET) program and 10 in a stretching and toning (SAT) program. The AET group was instructed to exercise based on their estimated maximal heart rate (HR) for 150 minutes weekly. The SAT group was to stretch for the same target time without significantly increasing HR or level of exertion. Outcome measures were Traumatic Brain Injury Quality of Life (TBI-QOL) for global, cognitive, emotional, and social health, Patient Health Questionnaire-9 (PHQ-9) for depressive symptoms, and Pittsburgh Sleep Quality Index (PSQI) for sleep quality. RESULTS: AET was associated with improved self-reported cognitive health and sleep compared to SAT. Moderate to large, positive effect sizes were also observed in the AET group in the QOL categories of global, emotional, and social health, and depressive symptoms. CONCLUSIONS: This study offers preliminary evidence that AET may improve health-related QOL, especially for cognition and sleep, in middle-aged and older adults with msTBI.


Assuntos
Lesões Encefálicas Traumáticas , Terapia por Exercício , Qualidade de Vida , Autorrelato , Humanos , Qualidade de Vida/psicologia , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Lesões Encefálicas Traumáticas/psicologia , Lesões Encefálicas Traumáticas/reabilitação , Terapia por Exercício/métodos , Idoso de 80 Anos ou mais , Estudos Prospectivos , Exercício Físico/psicologia , Exercício Físico/fisiologia
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