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1.
Langmuir ; 40(19): 9945-9956, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38691534

RESUMO

Intermittent oil-water wetting can have a significant effect on the internal corrosion of steel pipelines. This paper presents a combined experimental and molecular modeling study of several influential factors on the surface properties and corrosion behavior of mild steel in CO2 environments. The influence of different model oils (LVT-200 and Aromatic-200) and select surface-active compounds (myristic acid, cyclohexane butyric acid, and oleic acid) on the corrosion behavior of carbon steel during intermittent oil-water wetting was determined by measuring the corrosion rate after intermittent wetting cycles. The interfacial tension measurements were performed to study the incorporation of the oil phase along with surface-active molecules in the protective layer formed on the specimen surface. Results showed that the interfacial tension for an aromatic oil-water interface is lower than that for an aliphatic oil-water interface. To understand this result, molecular dynamics simulations of oil-water interfaces were performed in the presence of surface-active molecules and different oils to analyze the structure of the layer formed at the interface. The simulations supported the hypothesis that aromatic molecules are less structured at the interface, which results in the incorporation of more water molecules into the protective layer formed at the steel surface, causing a higher corrosion rate. On the other hand, the simulations revealed that myristic acid in an aliphatic oil forms a well-aligned structure at the interface, devoid of any water molecules. This is in agreement with the hypothesis that the linear molecular structure of myristic acid favors the alignment of molecules at an aliphatic oil-water interface, resulting in a lower interfacial tension and more effective corrosion mitigation as compared to the other two nonlinear compounds tested. It is concluded that an important factor controlling the corrosion behavior is the molecular structure of the oil-water interface, which is adopted by the steel surface layer through the Langmuir-Blodgett process.

2.
Ophthalmol Retina ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38719190

RESUMO

PURPOSE: In early 2022, a fluorescein shortage occurred in the United States. To meet the standard of care for patients who required ultra-wide fundus fluorescein angiography (UWFFA), a regimen of half-dose (250mg) sodium fluorescein (10%) was adopted instead of the full-dose (500mg) at the Cole Eye Institute (CEI). In this paper, we compare the image quality, clinical utility, and the side effect profile of half-dose vs full-dose fluorescein in UWFFA for a cohort of stable patients. DESIGN: Retrospective chart review. SUBJECTS, PARTICIPANTS, AND/OR CONTROLS: Patients with retinal vascular disease were included if they received half-dose and full-dose UWFFA (Optos California, Dunfermline, UK) within 6 months at the CEI. Eyes were excluded if they received intraocular injections, laser procedures, new immunosuppression, and worsened or improved inflammation on clinical examination. METHODS, INTERVENTION, OR TESTING: Quantitative assessment of vascular leakage was performed using a machine-learning enhanced automated segmentation platform. Leakage from late-phase UWFFA images was compared between half-dose and full-dose images. Qualitative assessment of image quality and relative vascular leakage was performed by 2 masked independent reviewers. Side effects after fluorescein administration were recorded for each patient. MAIN OUTCOME MEASURES: Masked leakage grading and automated leakage scores. RESULTS: There were 52 eyes of 35 patients, 42 (81%) uveitic, 5 (9%) diabetic, and 4 (8%) normal controls. Patients had no change to their visual acuity (LogMAR mean 0.3±0.6), anterior chamber and vitreous cell between UFFWA's. UWFFA images were deemed of equal quality and leakage by both masked reviewers (78-87% agreement, kappa 0.642). Automated leakage analysis showed mildly increased leakage in half-dose images overall (3.8% vs 2.8%, p=0.01), and in the macula (1.5% vs 0.6%, p=0.01). Side effects included nausea (half (n=3, 9%) vs full (n=2, 6%), p=0.69) and urticaria (n=0, 0% vs n=1, 2%, p=0.99) and were not different between doses. CONCLUSIONS: In this cohort, half dose UWFFA produced images that were of similar quality, clinical utility and with a similar side effect profile compared to full dose. Half dose UWFFA can be used to accurately assess the retinal vasculature and could be used primarily as a method to save cost and prevent waste.

3.
Cureus ; 16(3): e55384, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38562336

RESUMO

INTRODUCTION: The spleen is one of the frequently injured solid organs in abdominal blunt trauma. The standard of care is nonoperative nowadays depending on the hemodynamic stability (World Society of Emergency Surgery (WSES) grade I-III) of the patient due to advancements in treating modalities. Operative interventions are required in hemodynamically unstable patients or failure of nonoperative management. The study was planned to find the clinical spectrum of abdominal blunt trauma, specifically those having splenic trauma, and their subsequent management in an institution. METHODS: This is a retrospective observational study. All included patients with blunt abdominal injuries were treated in a level 1 trauma center between July 2021 and December 2022. Data regarding demographic profile, blood transfusion, pre- and postoperative findings, and management including the period of hospital stay, morbidity, and mortality were collected and analyzed. RESULTS: One hundred sixty-four patients were analyzed, of which 142 were males and 22 were females. The commonest mechanism of injury was motor vehicle collision, followed by falls. Grade III splenic injury was the most common injury, while the predominantly associated injury was rib fracture. The patients were managed preferably through nonoperative management, followed by angioembolization and operative management. The commonest postoperative complication was pneumonia. CONCLUSIONS: Nonoperative management of splenic trauma has evolved as the standard of care replacing operative management in order to sustain its immune function, thereby preventing overwhelming post-splenectomy infection.

4.
Ophthalmic Surg Lasers Imaging Retina ; 55(5): 270-277, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648428

RESUMO

BACKGROUND AND OBJECTIVE: This study compared the surgeon experience between conventional microscope-integrated intraoperative optical coherence tomography (iOCT) and digitally enabled microscope-integrated iOCT in vitreoretinal surgery. PATIENTS AND METHODS: This is a post hoc case-control analysis of the DISCOVER study. Conventional microscope-integrated iOCT (Rescan 700, Zeiss) was compared with digitally enabled iOCT (Artevo 800, Zeiss). Compared variables included surgical field-based visualization (ie, ocular heads-up display in the conventional group; three-dimensional screen-based visualization in the digital iOCT group) and non-surgical field-based visualization (ie, review on the external two-dimensional monitor). RESULTS: A total of 200 patients were included. Surgical field-based visualization of iOCT was significantly higher in the digitally enabled group (P < 0.0001). Required endoillumination level was significantly lower in the digital iOCT group (P < 0.0001). Surgeons reported "significant" back discomfort and headache more frequently when using conventional iOCT (P = 0.003 and P = 0.001, respectively). CONCLUSIONS: Digitally enabled iOCT resulted in greater surgical visualization efficiency, appeared to require a lower illumination level, and may provide advantages for ergonomic-related discomfort. [Ophthalmic Surg Lasers Imaging Retina 2024;55:270-277.].


Assuntos
Imageamento Tridimensional , Microscopia , Tomografia de Coerência Óptica , Cirurgia Vitreorretiniana , Humanos , Tomografia de Coerência Óptica/métodos , Masculino , Feminino , Imageamento Tridimensional/métodos , Microscopia/métodos , Pessoa de Meia-Idade , Estudos de Casos e Controles , Cirurgia Assistida por Computador/métodos , Idoso , Doenças Retinianas/cirurgia , Doenças Retinianas/diagnóstico
5.
Iran J Basic Med Sci ; 27(3): 326-334, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333757

RESUMO

Objectives: Neurological disorders are the world's most distressing problem. The adverse effects of current medications continue to compel scientists to seek safer, more effective, and economically affordable alternatives. In this vein, we explored the effect of D-Pinitol on isoproterenol-induced neurotoxicity in mice. Materials and Methods: Forty-two mice were randomly distributed into 7 groups each having 6 animals. Group I; received saline. Group II; received isoproterenol (ISO) 15 mg/kg/day, s.c. for 20 days. Group III, IV; received 50 and 100 mg/kg/day/oral of D-Pinitol, respectively along with ISO for 20 days. Group V; received D-Pinitol 100 mg/kg/day/oral for 20 days. Group VI; received propranolol 20 mg/kg/day/oral and ISO for 20 days. Group VII; received propranolol 20 mg/kg/day/oral for 20 days. On the 21st day after behavioral tests, blood was collected and mice were sacrificed for various biochemical, histopathological, and immunohistochemical analyses. Results: Chronic administration of isoproterenol caused neurotoxicity, cognitive dysfunction, and histopathological changes in the brain as evidenced by increase in GFAP, oxidative stress (via SOD, CAT, TBARS, and GSH), neuroinflammation (NF-kB, TNF-α, IL-6, and IL-10), and decrease in AchE and BDNF. Co-administration of D-Pinitol (100 mg/kg) significantly prevented these pathological alterations. The cognitive improvement was also observed through the forced swim test, elevated plus maze test, and rotarod test. Conclusion: Our findings on D-Pinitol thus clearly established its neuroprotective role in ISO-induced neurodegeneration in Swiss albino mice.

7.
Can J Ophthalmol ; 59(2): 128-136, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36878265

RESUMO

OBJECTIVE: Pentosan polysulfate (PPS; ELMIRON, Janssen Pharmaceuticals, Titusville, NJ) is a U.S. Food and Drug Administration-approved oral medication for interstitial cystitis. Numerous reports have been published detailing retinal toxicity with the use of PPS. Studies characterizing this condition are primarily retrospective, and consequently, alert and screening systems need to be developed to actively screen for this disease. The goal of this study was to characterize ophthalmic monitoring trends of a PPS-using patient sample to construct an alert and screening system for monitoring this condition. METHODS: A single-institution retrospective chart review was conducted between January 2005 and November 2020 to characterize PPS use. An electronic medical record (EMR) alert was constructed to trigger based on new PPS prescriptions and renewals offering ophthalmology referral. RESULTS: A total of 1407 PPS users over 15 years was available for characterization, with 1220 (86.7%) being female, the average duration of exposure being 71.2 ± 62.6 months, and the average medication cumulative exposure being 669.7 ± 569.2 g. A total of 151 patients (10.7%) had a recorded visit with an ophthalmologist, with 71 patients (5.0%) having optical coherence tomography imaging. The EMR alert fired for 88 patients over 1 year, with 34 patients (38.6%) either already being screened by an ophthalmologist or having been referred for screening. CONCLUSIONS: An EMR support tool can improve referral rates of PPS maculopathy screening with an ophthalmologist and may serve as an efficient method for longitudinal screening of this condition with the added benefit of informing pentosan polysulfate prescribers about this condition. Effective screening and detection may help determine which patients are at high risk for this condition.


Assuntos
Poliéster Sulfúrico de Pentosana , Doenças Retinianas , Humanos , Feminino , Masculino , Poliéster Sulfúrico de Pentosana/efeitos adversos , Estudos Retrospectivos , Olho , Doenças Retinianas/tratamento farmacológico , Face
8.
ACS Appl Bio Mater ; 7(2): 588-595, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-37141501

RESUMO

Glycogen synthase kinase 3 ß (GSK3ß) is a serine/threonine kinase that phosphorylates several protein substrates in crucial cell signaling pathways. Owing to its therapeutic importance, there is a need to develop GSK3ß inhibitors with high specificity and potency. One approach is to find small molecules that can allosterically bind to the GSK3ß protein surface. We have employed fully atomistic mixed-solvent molecular dynamics (MixMD) simulations to identify three plausible allosteric sites on GSK3ß that can facilitate the search for allosteric inhibitors. Our MixMD simulations narrow down the allosteric sites to precise regions on the GSK3ß surface, thereby improving upon the previous predictions of the locations of these sites.


Assuntos
Quinase 3 da Glicogênio Sintase , Simulação de Dinâmica Molecular , Glicogênio Sintase Quinase 3 beta , Ligantes , Sítios de Ligação
9.
Ophthalmol Retina ; 8(1): 10-17, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37673396

RESUMO

PURPOSE: A subset of patients with neovascular age-related macular degeneration (nAMD) experience treatment burden and suboptimal response with anti-VEGF therapy. The aim of this study was to investigate the effect of switching to a novel, bispecific agent, faricimab, in patients with nAMD currently treated with anti-VEGF. DESIGN: Retrospective, noncomparative cohort study. SUBJECTS: Patients with nAMD previously treated with anti-VEGF and switched to intravitreal faricimab injection (IFI) at the Cleveland Clinic's Cole Eye Institute. METHODS: Switching and administration schedule of IFI was at the discretion of the clinician. Visual acuity (VA) and macular OCT parameters, including central subfield thickness (CST), maximum pigment epithelial detachment (PED) height, and presence of subretinal (SRF) or intraretinal fluid (IRF), were assessed at baseline (day of first IFI) and after each IFI. MAIN OUTCOME MEASURES: Central subfield thickness and presence of IRF or SRF after ≥ 3 IFIs. RESULTS: One hundred twenty-six eyes of 106 patients were included in the analysis with a mean follow-up time of 24.3 ± 5.2 weeks. Before switching to IFI, patients received a mean of either aflibercept (20.0 ± 8.4, mean ± standard deviation), bevacizumab (7 ± 8.9), ranibizumab (1.9 ± 8.5), or brolucizumab (0.3 ± 1.6) injections. The most common agent used before switching to IFI was aflibercept (n = 110, 87%), and the mean treatment interval with any anti-VEGF was 5.6 ± 1.6 weeks before switching. Central subfield thickness was reduced from baseline after the first IFI (266.8 ± 64.7 vs. 249.8 ± 58.6 µm, P = 0.02) and persisted over the 3 IFIs (P = 0.01). Pigment epithelial detachment height was reduced after the third IFI (249.6 ± 179.0 vs. 206.9 ± 130.0 µm, P = 0.01). The mean VA (62.9 vs. 62.7 approximate ETDRS letters, P = 0.42) and interval between injections (6.3 vs. 5.7 weeks, P = 0.16) was similar after the third IFI compared with baseline. Eleven (8.7%) eyes were switched back to their previous anti-VEGF, including 2 (1.6%) eyes from 1 patient with intraocular inflammation requiring cessation of IFI. There were no other adverse events from switching. CONCLUSIONS: Switching to faricimab resulted in a reduction in mean CST (-11.6 µm, P = 0.01) and PED height (-44.2 µm, P = 0.01) after 3 injections, with stable VA and at a similar treatment interval to prior anti-VEGF therapy. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Assuntos
Degeneração Macular , Descolamento Retiniano , Humanos , Inibidores da Angiogênese , Estudos de Coortes , Estudos Retrospectivos , Resultado do Tratamento , Descolamento Retiniano/tratamento farmacológico , Degeneração Macular/tratamento farmacológico
10.
Artigo em Inglês | MEDLINE | ID: mdl-38105327

RESUMO

The availability of petroleum fuels is being challenged due to high demand and heavy dependence on imports, raising awareness of the need for cleaner alternatives. Urbanization, air quality, economic factors, and emissions limits motivate the search for alternative fuels compatible with compression ignition engines. A comprehensive bibliometric analysis further underscores the escalating worldwide research efforts in this critical domain. According to the existing literature, nitromethane and 2-ethoxy ethyl acetate have demonstrated superior physical and combustion properties compared to other additives. To explore their potential, a meticulous performance and emission analysis was conducted using a single-cylinder, 4-stroke VCR CI engine, employing varying proportions of 2-ethoxy ethyl acetate and a constant 2% blend of nitromethane, with EEA concentrations ranging from 5, 10, to 15% (v/v). This research delved into the influence of these diverse fuel blends on the performance of CI engines and exhaust characteristics within a compression ratio spectrum spanning from 17 to 20. The experimental findings revealed that ternary blends, although having a marginal impact on engine performance, exhibited lower emissions compared to pure diesel. The pinnacle of this investigation emerged with the EEA5NM2D93 blend, which yielded optimal results in terms of both performance and emission characteristics.

11.
J Vitreoretin Dis ; 7(6): 498-503, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37974923

RESUMO

Purpose: To evaluate the effect of syringe type on developing sustained intraocular pressure (IOP) increases. Methods: This retrospective cohort study included patients in a single academic center receiving antivascular endothelial growth factor (anti-VEGF) injections from 2012 to 2022 for various indications. Patients were grouped by anti-VEGF treatment of either vial-drawn or prefilled syringe delivery. Trends in IOP were recorded for 1 year after treatment began. Development of sustained IOP increase, ocular hypertension, and glaucoma was recorded. Sustained IOP increase was defined as ≥5 mm Hg above baseline for at least 4 weeks. Results: Of 257 total patients, 6 (2.3%) developed sustained IOP increases throughout the study's duration. No significant differences were noted with respect to prefilled versus vial-drawn syringe status on the development of sustained IOP increases or incident glaucoma (IOP: 1.8% vs 2.7%, respectively, P = .65; glaucoma: 0.0% vs 2.0%, respectively, P = .14). Patients treated with prefilled syringes were significantly less likely to develop ocular hypertension (2.8% vs 8.8%, P < .05). Conclusions: This study found that aflibercept intravitreal injection with prefilled syringes was not associated with a significant increase in IOP-related adverse effects when compared with those treated with vial-drawn syringes.

12.
Nat Commun ; 14(1): 6955, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907499

RESUMO

While studies on ambient fine particulate matter (PM2.5) exposure effect on child health are available, the differential effects, if any, of exposure to PM2.5 species are unexplored in lower and middle-income countries. Using multiple logistic regression, we showed that for every 10 µg m-3 increase in PM2.5 exposure, anaemia, acute respiratory infection, and low birth weight prevalence increase by 10% (95% uncertainty interval, UI: 9-11), 11% (8-13), and 5% (4-6), respectively, among children in India. NO3-, elemental carbon, and NH4+ were more associated with the three health outcomes than other PM2.5 species. We found that the total PM2.5 mass as a surrogate marker for air pollution exposure could substantially underestimate the true composite impact of different components of PM2.5. Our findings provide key indigenous evidence to prioritize control strategies for reducing exposure to more toxic species for greater child health benefits in India.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Criança , Humanos , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Saúde da Criança , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Material Particulado/análise , Índia/epidemiologia
13.
Animals (Basel) ; 13(19)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37835741

RESUMO

The purpose of this study was twofold: first, to conduct a situational analysis, and second, to assess the knowledge, attitudes, and practices (KAP) of broiler poultry farmers (BPF) regarding antimicrobial use (AMU) and antimicrobial resistance (AMR). Data were collected from 500 BPF across 40 districts, representing 88.1% of Nepal's broiler poultry population. Among these farmers, 81.0% were male, 59.6% had up to 4 years of experience in poultry farming, and 50.8% had completed at least a high school education. The most used antimicrobials on the farms were doxycycline (23.5%), neomycin (17.1%), and colistin sulfate (9.6%) out of 27 reported antimicrobials. While the BPF exhibited limited knowledge (62.6%) and practice (55.5%) related to AMU and AMR, their overall attitude toward these issues was positive (91.6%). This study also identified significant factors influencing farmers' attitudes toward AMU and AMR. Farmers aged 31-40 showed a stronger inclination compared to other age groups (OR = 4.2, p = 0.02), and those using antimicrobials for preventive purposes had a more favorable attitude compared to those using them for other purposes (OR = 5.9, p = 0.02). In light of these findings, this study recommends the implementation of effective regulatory measures for drug usage, along with awareness programs addressing AMU and AMR to address the issue of AMR in poultry production.

14.
Artigo em Inglês | MEDLINE | ID: mdl-37872339

RESUMO

The usage of graphene-based materials (GMs) as energy storage is incredibly popular. Significant obstacles now exist in the way of the generation, storage and consumption of sustainable energy. A primary focus in the work being done to advance environmentally friendly energy technology is the development of effective energy storage materials. Due to their distinct two-dimensional structure and intrinsic physical qualities like good electrical conductivity and wide area, graphene-based materials have a significant potential to be used in energy storage devices. Graphene and GMs have been employed extensively for this due to their special mechanical, thermal, catalytic and other functional qualities. In this review, we covered the topic of employing GMs to store hydrogen for green energy.

15.
Respir Med ; 219: 107422, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37827293

RESUMO

PURPOSE: To investigate the response to Acthar Gel® in patients with moderate to severe sarcoidosis uveitis. METHODS: This is a prospective open-label study that enrolled patients with moderate to severe sarcoidosis uveitis to receive 80 units daily of Acthar Gel for ten days followed by maintenance treatment with 80 units twice weekly. The primary outcome was the proportion of patients meeting at least one of the following variables 1) improved visual acuity, 2) resolution of intraocular inflammation, 3) ability to taper ocular or oral steroids by at least 50% or 4) reduction of cystoid macular edema, with no worsening of any single measure and no need for additional sarcoidosis therapies at 24 weeks. RESULTS: A total of nine patients were enrolled in the study. Four patients completed the full 24-week course of Acthar Gel, and three of these met the primary endpoint. Among the five patients who did not complete the 24-week course of treatment, four discontinued the treatment due to worsening ocular inflammation. One patient discontinued treatment due to severe adverse effects. The most common adverse effects were fluid retention (77%), insomnia (44%), hypertension (44%) and hyperglycemia (44%). CONCLUSIONS: We observed a clinical response to Acthar Gel in some patients with moderate to severe sarcoidosis uveitis, but a substantial proportion either failed to respond or did not tolerate the therapy. These observations may serve as preliminary data for controlled trials of Acthar Gel, but they do not support its role prior to failure of other agents.


Assuntos
Sarcoidose , Uveíte , Humanos , Estudos Prospectivos , Uveíte/tratamento farmacológico , Sarcoidose/complicações , Sarcoidose/tratamento farmacológico , Transtornos da Visão , Inflamação
16.
ACS Appl Mater Interfaces ; 15(37): 43810-43821, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37682231

RESUMO

Generation and utilization of green heat produced from solar energy demand broadband absorbers with the elusive combination of strong phonon-driven photon thermalization and, contrastingly, weak phonon-lattice thermal conductivity. Here, we report a new class of porous, nanostructured hard-carbon florets (NCFs) consisting of isotropically assembled conical microcavities for greater light entrapment and efficient broad-band absorption (95% over 250-2500 nm). Resembling marigolds, the NCF exhibits short-range graphitic order that promotes instantaneous and efficient solar-thermal conversion (ηSTC = 87%) while exhibiting long-range intrinsic disorder providing low thermal conductivity (1.5 W m-1 K-1) to minimize thermal loss (13%). Solution processable NCF coatings on arbitrarily substrates (filter paper, terracotta, Cu and Al tubes) generate surface temperature of 400 ± 2 K and exhibit high thermal effusance (519 W s0.5 m-2 K-1) to achieve highest combination of (a) rate of solar-driven interfacial water evaporation (Rw = 5.4 kg m-2 h-1, 2 sun), (b) solar-vapor conversion efficiency (ηSVC = 186%), and (c) ηSTC (87%) among known materials. Such robust performance is retained for beyond 30 days of continuous operation and under different solar power (1 sun to 5 sun). Furthermore, active space heating (outlet air temperature = 346 ± 3 K) using NCF coatings is demonstrated.

17.
JAMA Ophthalmol ; 141(9): 819-824, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37498609

RESUMO

Importance: Language-learning model-based artificial intelligence (AI) chatbots are growing in popularity and have significant implications for both patient education and academia. Drawbacks of using AI chatbots in generating scientific abstracts and reference lists, including inaccurate content coming from hallucinations (ie, AI-generated output that deviates from its training data), have not been fully explored. Objective: To evaluate and compare the quality of ophthalmic scientific abstracts and references generated by earlier and updated versions of a popular AI chatbot. Design, Setting, and Participants: This cross-sectional comparative study used 2 versions of an AI chatbot to generate scientific abstracts and 10 references for clinical research questions across 7 ophthalmology subspecialties. The abstracts were graded by 2 authors using modified DISCERN criteria and performance evaluation scores. Main Outcome and Measures: Scores for the chatbot-generated abstracts were compared using the t test. Abstracts were also evaluated by 2 AI output detectors. A hallucination rate for unverifiable references generated by the earlier and updated versions of the chatbot was calculated and compared. Results: The mean modified AI-DISCERN scores for the chatbot-generated abstracts were 35.9 and 38.1 (maximum of 50) for the earlier and updated versions, respectively (P = .30). Using the 2 AI output detectors, the mean fake scores (with a score of 100% meaning generated by AI) for the earlier and updated chatbot-generated abstracts were 65.4% and 10.8%, respectively (P = .01), for one detector and were 69.5% and 42.7% (P = .17) for the second detector. The mean hallucination rates for nonverifiable references generated by the earlier and updated versions were 33% and 29% (P = .74). Conclusions and Relevance: Both versions of the chatbot generated average-quality abstracts. There was a high hallucination rate of generating fake references, and caution should be used when using these AI resources for health education or academic purposes.


Assuntos
Inteligência Artificial , Olho , Humanos , Estudos Transversais , Alucinações , Educação em Saúde
18.
Ophthalmic Surg Lasers Imaging Retina ; 54(6): 330-336, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37352397

RESUMO

OBJECTIVES: To describe multimodal imaging findings of vitamin A deficiency retinopathy. METHODS: A retrospective study of patients with serum retinol < 0.3 mg/L. Fundus color photos, spectral domain-optical coherence tomography (SD-OCT), and fundus autofluorescence (FAF) were reviewed and, when available, electrophysiological tests were analyzed. RESULTS: Forty-five eyes (63.9 ± 15.7 years) were included. Ultra-widefield fundus photography showed drusen-like deposits (53.3%) and macular retinal pigment epithelium (RPE) mottling (40%). The deposits were hypoautofluorescent, and a perifoveal hyperautofluorescent ring was present in 8.9%. By SD-OCT, the ellipsoid zone had an irregular appearance (100%) and conical deposits anterior to the RPE (33.3%). Electroretinogram (ERG) (66.7%) showed a decrease in b-wave in the scotopic registers, and microperimetry (4.4%) showed decreased foveal sensitivity. After vitamin A supplementation, SD-OCT and FAF showed resolution of all findings. Forty percent of eyes had restoration of the scotopic registers in ERG and improved macular sensitivity by microperimetry (4.4%). CONCLUSIONS: Vitamin A deficiency causes a mild cone dysfunction in addition to the more severe absent rod response. [Ophthalmic Surg Lasers Imaging Retina 2023;54:330-336.].


Assuntos
Doenças Retinianas , Deficiência de Vitamina A , Humanos , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/diagnóstico , Estudos Retrospectivos , Retina , Transtornos da Visão , Tomografia de Coerência Óptica , Imagem Multimodal , Angiofluoresceinografia
19.
Biointerphases ; 18(3)2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37125848

RESUMO

We show, via molecular simulations, that not only does cholesterol induce a lipid order, but the lipid order also enhances cholesterol localization within the lipid leaflets. Therefore, there is a strong interdependence between these two phenomena. In the ordered phase, cholesterol molecules are predominantly present in the bilayer leaflets and orient themselves parallel to the bilayer normal. In the disordered phase, cholesterol molecules are mainly present near the center of the bilayer at the midplane region and are oriented orthogonal to the bilayer normal. At the melting temperature of the lipid bilayers, cholesterol concentration in the leaflets and the bilayer midplane is equal. This result suggests that the localization of cholesterol in the lipid bilayers is mainly dictated by the degree of ordering of the lipid bilayer. We validate our findings on 18 different lipid bilayer systems, obtained from three different phospholipid bilayers with varying concentrations of cholesterol. To cover a large temperature range in simulations, we employ the Dry Martini force field. We demonstrate that the Dry and the Wet Martini (with polarizable water) force fields produce comparable results.


Assuntos
Bicamadas Lipídicas , Fosfolipídeos , Temperatura , Colesterol , Água
20.
Iran J Basic Med Sci ; 26(5): 517-525, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37051097

RESUMO

Objectives: Cardiovascular diseases are widespread across the globe, and heart failure (HF) accounts for the majority of heart-associated deaths. Target-based drug therapy is much needed for the management of heart failure. We have designed this study to evaluate icariin for its cardioprotective activity in the isoproterenol (ISO) induced postinfarction model. We have randomly distributed Wistar rats into seven groups, i.e., vehicle control; isoproterenol-treated; icariin per se; sildenafil per se; ISO + icariin 5; ISO + icariin 10; and ISO + sildenafil groups. ISO (85 mg/kg, subcutaneous) was administered at 24 hr for two consecutive days to produce cardiac injury, followed by icariin administration at 5 mg/kg and 10 mg/kg orally for 56 days. Materials and Methods: Rats were subjected to hemodynamic measurements biweekly. After 24 hr of the completion of dosing, animals were sacrificed, and markers for oxidative stress, fibrosis, inflammation, and cell death were measured. Transmission electron microscopy (TEM), histopathology, and MT staining of cardiac tissue were also done to assess the pathological and fibrotic architectural damage. Results: A significant decline in hemodynamics and an anti-oxidant collapse were found in ISO-intoxicated rats. Alterations in the levels of cyclic guanosine monophosphate (cGMP), interleukin-10 (IL-10), Tumor necrosis factor (TNF-α), and brain natriuretic peptide (BNP) were also observed in serum. Up-regulation of caspase-3, nuclear factor (NF-ĸB), and decline in expression of nuclear factor (NrF-2) contribute to cardiac damage. The treatment with icariin and sildenafil considerably reversed the toxic changes toward normal. Conclusion: Increased cGMP and Nrf2 expression and suppressed NF-ĸB-caspase-3 signaling play a pivotal role in icariin-mediated cardioprotection.

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