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1.
Invest Ophthalmol Vis Sci ; 65(4): 4, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558092

RESUMO

Purpose: To examine lens phenotypic characteristics in ßA3ΔG91 mice and determine if ßA3ΔG91 affects autophagy in the lens. Methods: We generated a ßA3ΔG91 mouse model using CRISPR/Cas9 methodology. Comparative phenotypic and biochemical characterizations of lenses from postnatal day 0 (P0), P15, and 1-month-old ßA3ΔG91 and wild-type (WT) mice were performed. The methodologies used included non-invasive slit-lamp examination, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), western blot, and immunohistochemical (IHC) analyses to determine the levels of autophagy-related genes and proteins. Transmission electron microscopy (TEM) analysis of lenses was performed to assess organelle degradation and the presence of autophagic vesicles. TUNEL staining was used to determine apoptosis in the lens. Results: Relative to WT lenses, 1-month-old ßA3ΔG91 mice developed congenital nuclear cataract and microphthalmia and showed an early loss of endoplasmic reticulum (ER) in the cortex and attenuation of nuclei degradation. This observation was confirmed by TEM analysis, as was the presence of autophagic vesicles in ßA3ΔG91 lenses. Comparative IHC and RT-qPCR analyses showed relatively higher levels of autophagy markers (ubiquitinated proteins and p62, LC3, and LAMP2 proteins) in ßA3ΔG91 lenses compared to WT lenses. Additionally, ßA3ΔG91 lenses showed relatively greater numbers of apoptotic cells and higher levels of cleaved caspase-3 and caspase-9. Conclusions: The deletion of G91 in ßA3ΔG91 mice leads to higher levels of expression of autophagy-related proteins and their transcripts relative to WT lenses. Taken together, G91 deletion in ßA3/A1-crystallin is associated with autophagy disruption, attenuation of nuclei degradation, and cellular apoptosis in the lens, which might be congenital cataract causative factors.


Assuntos
Catarata , Cristalino , Camundongos , Animais , Catarata/genética , Catarata/metabolismo , Cristalino/metabolismo , Western Blotting , Modelos Animais de Doenças , Autofagia/genética
2.
Invest Ophthalmol Vis Sci ; 64(12): 40, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37750740

RESUMO

Purpose: To determine the role of fibroblast growth factor receptor 2 (FGFR2)-mediated signaling in keratocytes during corneal development, a keratocyte-specific FGFR2-knockout (named FGFR2cKO) mouse model was generated, and its phenotypic characteristics were determined. Methods: A FGFR2cKO mouse model was generated by the following method: FGFR2 flox mice were crossed with the inducible keratocyte specific-Cre mice (Kera-rtTA/tet-O-Cre). Both male and female FGFR2cKO- and control mice (1 to 3-months-old) were analyzed for changes in corneal topography and pachymetry maps using the optical coherence tomography (OCT) method. The comparative TUNEL assay and immunohistochemical analyses were performed using corneas of FGFR2cKO and control mice to determine apoptotic cells, and expression of collagen-1 and fibronectin. Transmission electron microscopic analysis was conducted to determine collagen structures and their diameters in corneas of FGFR2cKO and control mice. Results: OCT-analyses of corneas of FGFR2cKO mice (n = 24) showed localized central thinning and an increased corneal steepness compared to control mice (n = 23). FGFR2cKO mice further showed a decreased expression in collagen-1, decreased collagen diameters, acute corneal hydrops, an increased fibronectin expression, and an increased number of TUNEL-positive cells suggesting altered collagen structures and keratocytes' apoptosis in the corneas of FGFR2cKO mice compared to control mice. Conclusions: The FGFR2cKO mice showed several corneal phenotypes (as described above in the results) that are also exhibited by the human keratoconus corneas. The results suggested that the FGFR2cKO mouse model serves to elucidate not only the yet unknown role of FGFR2-mediated signaling in corneal physiology but also serves as a model to determine molecular mechanism of human keratoconus development.


Assuntos
Ceratocone , Animais , Feminino , Humanos , Lactente , Masculino , Camundongos , Colágeno/metabolismo , Córnea/metabolismo , Substância Própria/metabolismo , Fibronectinas/metabolismo , Ceratocone/genética , Ceratocone/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo
3.
Int J Biol Macromol ; 251: 126243, 2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37582430

RESUMO

Ascorbic acid (AA) is one of the important biomolecules involved in all phases of wound healing. The aim of this study was to develop a new hydrogel system that offers topical delivery of ascorbic acid to wounds during wound care management. In this work, we grafted poly (ethylene glycol) methacrylate onto a renewable biopolymer gellan, and the graft copolymer (GPMA) formed was crosslinked covalently and ionically, and used as a matrix for delivering AA to the wounds. By the processes of grafting and crosslinking, the mechanical properties of the gellan increased several fold compared to mechanically weak native gellan. In vitro cytotoxicity evaluation showed that GPMA was non-cytotoxic to fibroblast cells. GPMA hydrogel matrix allowed the sustained release of AA. When AA was incorporated in GPMA, a significant improvement in wound closure was observed in scratch wound assay performed with keratinocytes. Since AA acts as a cofactor in collagen synthesis, the controlled delivery of AA to the wound microenvironment favors the up-regulation of colα1 gene expression. This study revealed that ascorbic acid, at a concentration of 150 µM, has a favorable impact on wound healing when tested in vitro. Overall results indicate that the GPMA matrix could be a promising material for wound healing applications.

4.
Langmuir ; 39(16): 5779-5792, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37042262

RESUMO

In this study, dual-emissive carbon dots (CDs) were prepared using p-phenylenediamine (pPDA) and phytic acid (PA) precursors via a one-pot-hydrothermal method. The photophysical, morphological, and structural characterization of CDs was carried out using absorption, fluorescence, Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR), and high-resolution transmission electron microscopy (HR-TEM) analysis. The as-prepared CDs displayed dual-fluorescence peaks at 525 and 620 nm upon excitation at 450 nm. The CDs showed good photostability and exhibited solvent-dependent fluorescence properties. The solvatochromic behavior of CDs was utilized to detect water content in organic solvents. Furthermore, the dual-emissive property of CDs was utilized for the sequential detection of ferric (Fe3+) and pyrophosphate ions (PPi) by a fluorescence turn-off-on mechanism. The proposed assay showed appreciable fluorescence response toward Fe3+ and PPi with high selectivity and good tolerance for common interfering ions. The potential practical application of the CD probe was ascertained by carrying out the fluorometric detection of PPi to affirm the loop-mediated isothermal amplification (LAMP) reaction specific for Mycobacterium tuberculosis (negative and positive clinical samples).


Assuntos
Pontos Quânticos , Carbono/química , Pontos Quânticos/química , Ferro/química , Cátions , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Espectrometria de Fluorescência
5.
ACS Appl Bio Mater ; 6(5): 1742-1754, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37099324

RESUMO

The central nervous system has limited regeneration potential. The multipotency of adipose-derived mesenchymal stem cells (ADMSC) makes them an ideal autologous cell source for the regeneration of neural tissues. However, the likelihood of their differentiation into unwanted cell lineages when transplanted into a hostile injury environment is a serious disadvantage. Transplanting predifferentiated cells via an injectable carrier may aid in site-specific delivery for better survival of cells. Here, we focus on identifying an appropriate injectable hydrogel system that favors stem/progenitor cell attachment and differentiation for neural tissue engineering. An injectable composition of the hydrogel, derived from alginate dialdehyde (ADA) and gelatin, was formulated for this purpose. This hydrogel promoted proliferation/differentiation of ADMSCs to neural progenitors, visualized from the generation of prominent neurospheres and stage-specific expression of a neural progenitor marker (nestin, day 4), an intermittent neuronal marker (ß-III tub, day 5), and a mature neuronal marker (MAP-2, day 8) with neural branching and networking (>85%). The differentiated cells also expressed the functional marker synaptophysin. There was no negative impact on stem/progenitor cell survival (>95%) or differentiation (∼90%) as compared to two-dimensional (2D) culture. Addition of appropriate quantities of asiatic acid specific for neural niche supported cell growth and differentiation without affecting cell survival (>90%) and improved neural branching and elongation. Optimized interconnected porous hydrogel niche exhibited rapid gelation (3 min) and self-healing properties mimicking native neural tissue. Both ADA-gelatin hydrogel by itself and that incorporated with asiatic acid were found to support stem/neural progenitor cell growth and differentiation and have potential applications as antioxidants and growth promoters upon release at the cell transplantation site. In short, the matrix itself or incorporated with phytomoieties could serve as a potential minimally invasive injectable cell delivery vehicle for cell-based therapies of neural diseases.


Assuntos
Células-Tronco Mesenquimais , Células-Tronco Neurais , Ratos , Animais , Hidrogéis/metabolismo , Engenharia Tecidual/métodos , Gelatina/farmacologia , Gelatina/metabolismo , Alginatos , Células Cultivadas , Células-Tronco Mesenquimais/metabolismo
6.
PLoS One ; 18(3): e0281386, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36989286

RESUMO

ßA3/A1-crystallin is a lens structural protein that plays an important role in maintaining lens transparency via interactions with other crystallins. While the function of ßA3/A1-crystallin in the retina is well studied, its functions in the lens, other than as a structural protein, remain unclear. In the current study, we generated the lens-specific ßA3/A1-crystallin conditional knockout mouse (named ßA3/A1ckO) and explored phenotypic changes and the function of the crystallin in the lens. The ßA3/A1ckO mice showed congenital cataract at birth and exhibited truncation of lens proteins. Several truncated protein fragments were recovered as a pellet during a low-speed centrifugation (800 rpm, 70 x g) followed by a relatively higher speed centrifugation (5000 rpm, 2744 x g). Mass spectrometric analysis of pellets recovered following the two centrifugations showed that among the fragments with Mr < 20 kDa, the majority of these were from ß-tubulin, and some from phakinin, αA-crystallin, and calpain-3. Further, we observed that in vitro activation of calpain-3 by calcium treatment of the wild-type-lens homogenate resulted in the degradation of calpain-3, αA-crystallin and ß-tubulin and insolubilization of these proteins. Based on these results, it was concluded that the activation of calpain 3 resulted in proteolysis of ß-tubulin, which disrupted cellular microtubular structure, and caused proteolysis of other lens proteins (αA-crystallin and phakinin). These proteolyzed protein fragments become insoluble, and together with the disruption of microtubular structure, and could be the causative factors in the development of congenital nuclear cataract in ßA3/A1cKO mice.


Assuntos
Catarata , Cristalinas , Cristalino , Animais , Camundongos , Calpaína/genética , Calpaína/metabolismo , Catarata/genética , Catarata/metabolismo , Cristalinas/genética , Cristalinas/metabolismo , Cristalino/metabolismo , Camundongos Knockout , Proteólise , Tubulina (Proteína)/metabolismo
7.
JMIR Form Res ; 7: e40403, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36693148

RESUMO

BACKGROUND: Since the advent of the COVID-19 pandemic, individuals of Asian descent (colloquial usage prevalent in North America, where "Asian" is used to refer to people from East Asia, particularly China) have been the subject of stigma and hate speech in both offline and online communities. One of the major venues for encountering such unfair attacks is social networks, such as Twitter. As the research community seeks to understand, analyze, and implement detection techniques, high-quality data sets are becoming immensely important. OBJECTIVE: In this study, we introduce a manually labeled data set of tweets containing anti-Asian stigmatizing content. METHODS: We sampled over 668 million tweets posted on Twitter from January to July 2020 and used an iterative data construction approach that included 3 different stages of algorithm-driven data selection. Finally, we found volunteers who manually annotated the tweets by hand to arrive at a high-quality data set of tweets and a second, more sampled data set with higher-quality labels from multiple annotators. We presented this final high-quality Twitter data set on stigma toward Chinese people during the COVID-19 pandemic. The data set and instructions for labeling can be viewed in the Github repository. Furthermore, we implemented some state-of-the-art models to detect stigmatizing tweets to set initial benchmarks for our data set. RESULTS: Our primary contributions are labeled data sets. Data Set v3.0 contained 11,263 tweets with primary labels (unknown/irrelevant, not-stigmatizing, stigmatizing-low, stigmatizing-medium, stigmatizing-high) and tweet subtopics (eg, wet market and eating habits, COVID-19 cases, bioweapon). Data Set v3.1 contained 4998 (44.4%) tweets randomly sampled from Data Set v3.0, where a second annotator labeled them only on the primary labels and then a third annotator resolved conflicts between the first and second annotators. To demonstrate the usefulness of our data set, preliminary experiments on the data set showed that the Bidirectional Encoder Representations from Transformers (BERT) model achieved the highest accuracy of 79% when detecting stigma on unseen data with traditional models, such as a support vector machine (SVM) performing at 73% accuracy. CONCLUSIONS: Our data set can be used as a benchmark for further qualitative and quantitative research and analysis around the issue. It first reaffirms the existence and significance of widespread discrimination and stigma toward the Asian population worldwide. Moreover, our data set and subsequent arguments should assist other researchers from various domains, including psychologists, public policy authorities, and sociologists, to analyze the complex economic, political, historical, and cultural underlying roots of anti-Asian stigmatization and hateful behaviors. A manually annotated data set is of paramount importance for developing algorithms that can be used to detect stigma or problematic text, particularly on social media. We believe this contribution will help predict and subsequently design interventions that will significantly help reduce stigma, hate, and discrimination against marginalized populations during future crises like COVID-19.

8.
Mol Vis ; 28: 147-164, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36540064

RESUMO

Purpose: To identify and characterize properties of αA- and αB-crystallins' low molecular weight peptides (molecular weight [Mr] < 5 kDa) that were present in a 62-year-old human nuclear cataract, but not in normal 62-year-old human lenses. Methods: Low molecular weight peptides (< 5 kDa) were isolated with a trichloroacetic acid (TCA) solubilization method from water-soluble (WS) and water-insoluble (WI) proteins of nuclear cataractous lenses of a 62-year-old donor and normal human lenses from an age-matched donor. Five commercially synthesized peptides (found only in cataractous lenses and not in normal lenses) were used to determine their chaperone and antichaperone activity and aggregation properties. Results: Mass spectrometric analysis showed 28 peptides of αA-crystallin and 38 peptides of αB-crystallin were present in the cataractous lenses but not in the normal lenses. Two αA peptides (named αAP1 and αAP2; both derived from the αA N-terminal domain (NTD) region) and three αB peptides (named αBP3, αBP4, and αBP5, derived from the αB NTD-, core domain (CD), and C-terminal extension (CTE) regions, respectively) were commercially synthesized. αAP1 inhibited the chaperone activity of αA- and αB-crystallins, but the other four peptides (αAP2, αBP3, αBP4, and αBP5) exhibited mixed effects on chaperone activity. Upon incubation with human WS proteins and peptides in vitro, the αBP4 peptide showed higher aggregation properties relative to the αAP1 peptide. During in vivo experiments, the cell-penetrating polyarginine-labeled αAP1 and αBP4 peptides showed 57% and 85% aggregates, respectively, around the nuclei of cultured human lens epithelial cells compared to only 35% by a scrambled peptide. Conclusions: The antichaperone activity of the αAP1 peptide and the aggregation property of the αBP4 peptide with lens proteins could play a potential role during the development of lens opacity.


Assuntos
Catarata , Cristalinas , Cristalino , Humanos , Pessoa de Meia-Idade , Cristalinas/química , Cristalino/metabolismo , Catarata/metabolismo , Peptídeos/farmacologia , Peptídeos/metabolismo , Água/metabolismo
10.
J Bioeth Inq ; 19(2): 327-339, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35420376

RESUMO

High degrees of uncertainty and a lack of effective therapeutic treatments have characterized the COVID-19 pandemic and the provision of drug products outside research settings has been controversial. International guidelines for providing patients with experimental interventions to treat infectious diseases outside of clinical trials exist but it is unclear if or how they should apply in settings where clinical trials and research are strongly regulated. We propose the Professional Oversight of Emergency-Use Interventions and Monitoring System (POEIMS) as an alternative pathway based on guidance developed for the ethical provision of experimental interventions to treat COVID-19 in Singapore. We support our proposal with justifications that establish moral duties for physicians to record outcomes data and for institutions to establish monitoring systems for reporting information on safety and effectiveness to the relevant authorities. Institutions also have a duty to support generation of evidence for what constitutes good clinical practice and so should ensure the unproven intervention is made the subject of research studies that can contribute to generalizable knowledge as soon as practical and that physicians remain committed to supporting learning health systems. We outline key differences between POEIMS and other pathways for the provision of experimental interventions in public health emergencies.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Obrigações Morais , Pandemias , Saúde Pública , Singapura/epidemiologia
11.
ACS Omega ; 7(8): 6795-6809, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35252674

RESUMO

Combating antibiotic resistance has found great interest in the current clinical scenario. Pseudomonas aeruginosa, an opportunistic multidrug-resistant pathogen, is well known for its deadly role in hospital-acquired infections. Infections by P. aeruginosa are among the toughest to treat because of its intrinsic and acquired resistance to antibiotics. In this study, we project gallium-curcumin nanoparticle (GaCurNP) conjugates as a prospective candidate to fight against P. aeruginosa. The synthesized GaCurNPs were spherical with an average size ranging from 25-35 nm. Analysis by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy deduced the nature of interaction between gallium and curcumin. Conjugate formation with gallium was found to improve the stability of curcumin at the physiological pH. When tested after 24 h of contact, at the physiological pH and 37 °C, the degradation of curcumin bound in the GaCurNPs was 26%, while that of native curcumin was 95%. The minimum inhibitory concentration (MIC) of GaCurNPs was found to be 82.75 µg/mL for P. aeruginosa (ATCC 27853). GaCurNPs also showed excellent biofilm inhibition at 4MIC concentration. Raman spectroscopic analysis showed that GaCurNPs are capable of disrupting the cells of P. aeruginosa within 3 h of contact. Live/dead imaging also confirmed the compromised membrane integrity in cells treated with GaCurNPs. Scanning electron microscopy analysis showed membrane lysis and cell structure damage. The AlamarBlue assay showed that when L929 cell lines were treated with GaCurNPs with concentrations as high as 350 µg/mL, the cell viability elicited by the nanoparticles was 70.89%, indicating its noncytotoxic nature. In short, GaCurNPs appear to be a promising antibacterial agent capable of fighting a clinically significant pathogen, P. aeruginosa.

12.
J Biomater Appl ; 36(7): 1254-1268, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34802323

RESUMO

This report demonstrates the development of a degradable quaternary ammonium derivative of chitosan (QC) composited with strontium-containing nanoapatite (SA) for bioactivity. The material was made as porous membrane by solution casting and freeze drying, for guided tissue regeneration (GTR) applications. The micromorphology, tensile strength, suture pull-out strength, degradation (in vitro, in phosphate buffered saline), and cytocompatibility (using human periodontal ligament cells) were tested to investigate the effect of derivatization and SA addition. The porosity of the membranes increased with increasing SA content and so did the tensile strength and the degradation. The suture pull-out strength, however, showed a decrease. The cell culture evaluation endorsed biocompatibility. The composite with 1.5 mg SA per 1 mL QC was found to have optimal qualities for GTR applications.


Assuntos
Quitosana , Regeneração Tecidual Guiada , Materiais Biocompatíveis/farmacologia , Regeneração Óssea , Quitosana/farmacologia , Humanos , Membranas Artificiais , Porosidade , Estrôncio/farmacologia
13.
ACS Omega ; 6(38): 24826-24833, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34604664

RESUMO

A radiopaque compound, namely, 4,4-bis(4-hydroxy-3,5-diiodophenyl)pentanoic acid, was synthesized by the electrophilic aromatic iodination of 4,4-bis(4-hydroxyphenyl)pentanoic acid using sodium iodide and sodium hypochlorite. The active iodines created by hypochlorite were selectively bound to the ortho positions of the diphenolic acid and obtained a tetraiodo compound. Characterization of this iodinated compound was accomplished by routine methods such as Fourier transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance (NMR) spectroscopy, energy-dispersive X-ray spectroscopy, mass spectroscopy, UV-Vis spectroscopy, and thermogravimetry. The iodine content in the compound was as high as 64% by weight and therefore expected to possess substantial radiopacity. A 5% solution of the compound in dimethyl sulfoxide exhibited radiopacity of 885 ± 7 Hounsfield Units when tested with computed tomography (CT) scanner. In vitro cytotoxicity test performed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay demonstrated that the compound was noncytotoxic to L929 fibroblast cells up to the level of 0.8 mg/mL concentration. Overall results indicate that this highly radiopaque compound has the potential to be used for X-ray imaging in the clinical scenario.

14.
BMC Med ; 19(1): 244, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34645429

RESUMO

BACKGROUND: Global progress towards reducing tuberculosis (TB) incidence and mortality has consistently lagged behind the World Health Organization targets leading to a perception that large reductions in TB burden cannot be achieved. However, several recent and historical trials suggest that intervention efforts that are comprehensive and intensive can have a substantial epidemiological impact. We aimed to quantify the potential epidemiological impact of an intensive but realistic, community-wide campaign utilizing existing tools and designed to achieve a "step change" in the TB burden. METHODS: We developed a compartmental model that resembled TB transmission and epidemiology of a mid-sized city in India, the country with the greatest absolute TB burden worldwide. We modeled the impact of a one-time, community-wide screening campaign, with treatment for TB disease and preventive therapy for latent TB infection (LTBI). This one-time intervention was followed by the strengthening of the tuberculosis-related health system, potentially facilitated by leveraging the one-time campaign. We estimated the tuberculosis cases and deaths that could be averted over 10 years using this comprehensive approach and assessed the contributions of individual components of the intervention. RESULTS: A campaign that successfully screened 70% of the adult population for active and latent tuberculosis and subsequently reduced diagnostic and treatment delays and unsuccessful treatment outcomes by 50% was projected to avert 7800 (95% range 5450-10,200) cases and 1710 (1290-2180) tuberculosis-related deaths per 1 million population over 10 years. Of the total averted deaths, 33.5% (28.2-38.3) were attributable to the inclusion of preventive therapy and 52.9% (48.4-56.9) to health system strengthening. CONCLUSIONS: A one-time, community-wide mass campaign, comprehensively designed to detect, treat, and prevent tuberculosis with currently existing tools can have a meaningful and long-lasting epidemiological impact. Successful treatment of LTBI is critical to achieving this result. Health system strengthening is essential to any effort to transform the TB response.


Assuntos
Epidemias , Tuberculose Latente , Tuberculose , Adulto , Humanos , Incidência , Índia/epidemiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
15.
Singapore Med J ; 62(11): 604-609, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32312027

RESUMO

INTRODUCTION: Easy access and availability of communication tools have facilitated doctors' communication, adding new challenges. Through this study, we aimed to determine the profile of the knowledge and practices of doctors in our institution, and to identify knowledge gaps in the use of social media accounts. METHODS: An anonymous survey was sent by electronic mail in March-May 2018 to 931 doctors working in National University Hospital, Singapore. It included questions on demographics; use of social media; and case-based scenarios involving professionalism, patient-doctor relationship and personal practices of social media use. RESULTS: The response rate was 12.8%. The majority of the respondents owned a social media account (93.3%), had not received education on social media use in medical school (84.0%), did not own a separate work phone (80.7%) and claimed to have no medical education on this as a doctor (58.8%). Unawareness of the institution's social media policy was reported by 14.3% of the respondents. Questions on knowledge of the privacy settings of their account were incorrectly answered. Only 75.6%-82.4% of the participants responded 'no' when asked if they would post pictures of patients or their results, even if there were no patient identifiers. CONCLUSION: There is inadequate knowledge regarding institutional social media policy and privacy settings of social media accounts among doctors. Regarding practices in social media use, while most agree that caution should be exercised for online posts involving patients, ambiguity still exists. The emerging knowledge deficit and potentially unsafe practices that are identified can be addressed through continuing medical education and training on social media use.


Assuntos
Médicos , Mídias Sociais , Humanos , Conhecimento , Relações Médico-Paciente , Profissionalismo
16.
Int J Biol Macromol ; 166: 999-1008, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33166555

RESUMO

INTRODUCTION: Development of a tissue-engineered construct for hepatic regeneration remains a challenging task due to the lack of an optimum environment that support the growth of hepatocytes. Hydrogel systems possess many similarities with tissues and have the potential to provide the microenvironment essential for the cells to grow, proliferate, and remain functionally active. METHODS: In this work, fibrin (FIB) incorporated injectable alginate dialdehyde (ADA) - gelatin (G) hydrogel was explored as a matrix for liver tissue engineering. ADA was prepared by periodate oxidation of sodium alginate. An injectable formulation of ADA-G-FIB hydrogel was prepared and characterized by FTIR spectroscopy, Scanning Electron Microscopy, and Micro-Computed Tomography. HepG2 cells were cultured on the hydrogel system; cellular growth and functions were analyzed using various functional markers. RESULTS: FTIR spectra of ADA-G-FIB depicted the formation of Schiff's base at 1608.53 cm-1 with a gelation time of 3 min. ADA-G-FIB depicted a 3D surface topography with a pore size in the range of 100-200 µm. The non-cytotoxic nature of the scaffold was demonstrated using L929 cells and more than 80 % cell viability was observed. Functional analysis of cultured HepG2 cells demonstrated ICG uptake, albumin synthesis, CYP-P450 expression, and ammonia clearance. CONCLUSION: ADA-G-FIB hydrogel can be used as an effective 3D scaffold system for liver tissue engineering.


Assuntos
Alginatos/química , Fibrina/análogos & derivados , Hidrogéis/síntese química , Regeneração Hepática , Engenharia Tecidual/métodos , Tecidos Suporte/química , Aldeídos/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Gelatina/química , Células Hep G2 , Humanos , Hidrogéis/efeitos adversos , Camundongos , Tecidos Suporte/efeitos adversos
17.
BMC Ophthalmol ; 20(1): 484, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33302904

RESUMO

We have generated two mouse models, in one by inserting the human lens αAN101D transgene in CRYαAN101D mice, and in the other by inserting human wild-type αA-transgene in CRYαAWT mice. The CRYαAN101D mice developed cortical cataract at about 7-months of age relative to CRYαAWT mice. The objective of the study was to determine the following relative changes in the lenses of CRYαAN101D- vs. CRYαAWT mice: age-related changes with specific emphasis on protein insolubilization, relative membrane-association of αAN101D vs. WTαA proteins, and changes in intracellular ionic imbalance and membrane organization. METHODS: Lenses of varying ages from CRYαAWT and CRYαAN101D mice were compared for an age-related protein insolubilization. The relative lens membrane-association of the αAN101D- and WTαA proteins in the two types of mice was determined by immunohistochemical-, immunogold-labeling-, and western blot analyses. The relative levels of membrane-binding of recombinant αAN101D- and WTαA proteins was determined by an in vitro assay, and the levels of intracellular Ca2+ uptake and Na, K-ATPase mRNA were determined in the cultured epithelial cells from lenses of the two types of mice. RESULTS: Compared to the lenses of CRYαAWT, the lenses of CRYαAN101D mice exhibited: (A) An increase in age-related protein insolubilization beginning at about 4-months of age. (B) A greater lens membrane-association of αAN101D- relative to WTαA protein during immunogold-labeling- and western blot analyses, including relatively a greater membrane swelling in the CRYαAN101D lenses. (C) During in vitro assay, the greater levels of binding αAN101D- relative to WTαA protein to membranes was observed. (D) The 75% lower level of Na, K-ATPase mRNA but 1.5X greater Ca2+ uptake were observed in cultured lens epithelial cells of CRYαAN101D- than those of CRYαAWT mice. CONCLUSIONS: The results show that an increased lens membrane association of αAN101D--relative WTαA protein in CRYαAN101D mice than CRYαAWT mice occurs, which causes intracellular ionic imbalance, and in turn, membrane swelling that potentially leads to cortical opacity.


Assuntos
Catarata , Cristalinas , Cristalino , Animais , Animais Geneticamente Modificados , Western Blotting , Catarata/genética , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos
18.
Artigo em Inglês | MEDLINE | ID: mdl-32829135

RESUMO

Sirolimus, a lipophilic macrolide, is a well-known immunosuppressant drug used for coating coronary stents and for preventing rejection of kidney transplants in humans. Since Sirolimus is a relatively large molecule with an average mass 914.172 g/mol, size exclusion chromatography (SEC) was employed for exploring its potential for the estimation of Sirolimus content from blood samples. When human blood samples were spiked with known concentrations of Sirolimus, it was observed that it could be estimated with an average recovery of >90% and relative standard deviation <5%. Results indicated that Sirolimus could be estimated with impressive accuracy and repeatability by SEC technique.


Assuntos
Cromatografia em Gel/métodos , Sirolimo/sangue , Cromatografia Líquida de Alta Pressão , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
19.
Asian Spine J ; 14(5): 742-759, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32718133

RESUMO

Spinal epidural abscess (SEA) is a rare condition associated with significant morbidity and mortality. Despite advances in diagnostic medicine, early recognition of SEAs remains elusive. The vague presentation of the disease, coupled with its numerous risk factors, the diagnostic requirement for obtaining advanced imaging, and the necessity of specialized care constitute extraordinary challenges to both diagnosis and treatment of SEA. Once diagnosed, SEAs require urgent or emergent medical and/or surgical management. As SEAs are a relatively rare pathology, high-quality data are limited and there is no consensus on their optimal management. This paper focuses on presenting the treatment modalities that have been successful in the management of SEAs and providing a critical assessment of how specific SEA characteristics may render one infection more amenable to primary surgical or medical interventions. This paper reviews the relevant history, epidemiology, clinical presentation, radiology, microbiology, and treatment of SEAs and concludes by addressing the medicolegal implications of delayed treatment of the disease.

20.
Am J Health Syst Pharm ; 77(15): 1231-1236, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32620966

RESUMO

PURPOSE: To describe the benefits of smart infusion pump interoperability with an electronic medical record (EMR) system in an adult intensive care unit (ICU) setting. SUMMARY: In order to assess the impact of smart infusion pump and EMR interoperability, we observed whether there were changes in the frequency of electronic medication administration record (eMAR) documentation of dose titrations in epinephrine and norepinephrine infusions in the ICU setting. As a secondary endpoint, we examined whether smart pump/EMR interoperability had any impact on the rate of alerts triggered by the dose-error reduction software. Pharmacist satisfaction was measured to determine the impact of smart pump/EMR interoperability on pharmacist workflow. In the preimplementation phase, there were a total of 2,503 administrations of epinephrine and norepinephrine; 13,299 rate changes were documented, for an average of 5.31 documented rate changes per administration. With smart pump interoperability, a total of 13,024 rate changes were documented in association with 1,401 administrations, for an average of 9.29 documented rate changes per administration (a 74.9% increase). A total of 1,526 dose alerts were triggered in association with 76,145 infusions in the preimplementation phase; there were 820 dose alerts associated with 48,758 autoprogammed infusions in the postimplementation phase (absolute difference, -0.32%). ICU pharmacists largely agreed (75% of survey respondents) that the technology provided incremental value in providing patient care. CONCLUSION: Interoperability between the smart pump and EMR systems proved beneficial in the administration and monitoring of continuous infusions in the ICU setting. Additionally, ICU pharmacists may be positively impacted by improved clinical data accuracy and operational efficiency.


Assuntos
Cuidados Críticos/tendências , Registros Eletrônicos de Saúde/tendências , Interoperabilidade da Informação em Saúde/tendências , Bombas de Infusão/tendências , Unidades de Terapia Intensiva/tendências , Centros Médicos Acadêmicos/normas , Centros Médicos Acadêmicos/tendências , Cuidados Críticos/normas , Registros Eletrônicos de Saúde/normas , Determinação de Ponto Final/normas , Determinação de Ponto Final/tendências , Interoperabilidade da Informação em Saúde/normas , Humanos , Bombas de Infusão/normas , Unidades de Terapia Intensiva/normas
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