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1.
Talanta ; 262: 124701, 2023 Sep 01.
Article in English | MEDLINE | ID: covidwho-2324697

ABSTRACT

Fast and effective diagnosis is the first step in monitoring the current coronavirus 2 (CoV-2) pandemic. Herein, we establish a simple and sensitive electrochemical assay using magnetic nanocomposite and DNA sandwich probes to rapidly quantify the CoV-2 nucleocapsid (N) gene down to the 0.37 fM level. This assay uses a pair of specific DNA probes. The capture probe is covalently conjugated to Au-decorated magnetic reduced graphene oxide (AMrGO) nanocomposite for efficiently capturing target RNA. In contrast, the detection probe is linked to peroxidase for signal amplification. The probes target the COV-2 gene, allowing for specific magnetic separation, enzymatic signal amplification, and subsequent generation of voltammetric current with a total assay time of 45 min. The developed biosensor has high selectivity and can discriminate non-specific gene sequences. Synthetic COV-2 N-gene can be detected efficiently in serum and saliva, while 1-bp mismatch gene yielded a low response. The performance of the genosensor was good in an extensive linear range of 5 aM-50 pM. For synthetic N-gene, we achieved the detection limit of 0.37, 0.33, and 0.19 fM in human saliva, urine, and serum. This simple, selective, and sensitive genosensor could have various genetics-based biosensing and diagnostic applications.


Subject(s)
Biosensing Techniques , COVID-19 , Graphite , Nanocomposites , Humans , SARS-CoV-2/genetics , Graphite/chemistry , Nanocomposites/chemistry , Nucleocapsid , Electrochemical Techniques , Gold/chemistry
2.
Front Med (Lausanne) ; 9: 875242, 2022.
Article in English | MEDLINE | ID: covidwho-2261539

ABSTRACT

Background: Many artificial intelligence (AI) studies have focused on development of AI models, novel techniques, and reporting guidelines. However, little is understood about clinicians' perspectives of AI applications in medical fields including ophthalmology, particularly in light of recent regulatory guidelines. The aim for this study was to evaluate the perspectives of ophthalmologists regarding AI in 4 major eye conditions: diabetic retinopathy (DR), glaucoma, age-related macular degeneration (AMD) and cataract. Methods: This was a multi-national survey of ophthalmologists between March 1st, 2020 to February 29th, 2021 disseminated via the major global ophthalmology societies. The survey was designed based on microsystem, mesosystem and macrosystem questions, and the software as a medical device (SaMD) regulatory framework chaired by the Food and Drug Administration (FDA). Factors associated with AI adoption for ophthalmology analyzed with multivariable logistic regression random forest machine learning. Results: One thousand one hundred seventy-six ophthalmologists from 70 countries participated with a response rate ranging from 78.8 to 85.8% per question. Ophthalmologists were more willing to use AI as clinical assistive tools (88.1%, n = 890/1,010) especially those with over 20 years' experience (OR 3.70, 95% CI: 1.10-12.5, p = 0.035), as compared to clinical decision support tools (78.8%, n = 796/1,010) or diagnostic tools (64.5%, n = 651). A majority of Ophthalmologists felt that AI is most relevant to DR (78.2%), followed by glaucoma (70.7%), AMD (66.8%), and cataract (51.4%) detection. Many participants were confident their roles will not be replaced (68.2%, n = 632/927), and felt COVID-19 catalyzed willingness to adopt AI (80.9%, n = 750/927). Common barriers to implementation include medical liability from errors (72.5%, n = 672/927) whereas enablers include improving access (94.5%, n = 876/927). Machine learning modeling predicted acceptance from participant demographics with moderate to high accuracy, and area under the receiver operating curves of 0.63-0.83. Conclusion: Ophthalmologists are receptive to adopting AI as assistive tools for DR, glaucoma, and AMD. Furthermore, ML is a useful method that can be applied to evaluate predictive factors on clinical qualitative questionnaires. This study outlines actionable insights for future research and facilitation interventions to drive adoption and operationalization of AI tools for Ophthalmology.

3.
Frontiers in medicine ; 9, 2022.
Article in English | EuropePMC | ID: covidwho-2092500

ABSTRACT

Background Many artificial intelligence (AI) studies have focused on development of AI models, novel techniques, and reporting guidelines. However, little is understood about clinicians' perspectives of AI applications in medical fields including ophthalmology, particularly in light of recent regulatory guidelines. The aim for this study was to evaluate the perspectives of ophthalmologists regarding AI in 4 major eye conditions: diabetic retinopathy (DR), glaucoma, age-related macular degeneration (AMD) and cataract. Methods This was a multi-national survey of ophthalmologists between March 1st, 2020 to February 29th, 2021 disseminated via the major global ophthalmology societies. The survey was designed based on microsystem, mesosystem and macrosystem questions, and the software as a medical device (SaMD) regulatory framework chaired by the Food and Drug Administration (FDA). Factors associated with AI adoption for ophthalmology analyzed with multivariable logistic regression random forest machine learning. Results One thousand one hundred seventy-six ophthalmologists from 70 countries participated with a response rate ranging from 78.8 to 85.8% per question. Ophthalmologists were more willing to use AI as clinical assistive tools (88.1%, n = 890/1,010) especially those with over 20 years' experience (OR 3.70, 95% CI: 1.10–12.5, p = 0.035), as compared to clinical decision support tools (78.8%, n = 796/1,010) or diagnostic tools (64.5%, n = 651). A majority of Ophthalmologists felt that AI is most relevant to DR (78.2%), followed by glaucoma (70.7%), AMD (66.8%), and cataract (51.4%) detection. Many participants were confident their roles will not be replaced (68.2%, n = 632/927), and felt COVID-19 catalyzed willingness to adopt AI (80.9%, n = 750/927). Common barriers to implementation include medical liability from errors (72.5%, n = 672/927) whereas enablers include improving access (94.5%, n = 876/927). Machine learning modeling predicted acceptance from participant demographics with moderate to high accuracy, and area under the receiver operating curves of 0.63–0.83. Conclusion Ophthalmologists are receptive to adopting AI as assistive tools for DR, glaucoma, and AMD. Furthermore, ML is a useful method that can be applied to evaluate predictive factors on clinical qualitative questionnaires. This study outlines actionable insights for future research and facilitation interventions to drive adoption and operationalization of AI tools for Ophthalmology.

5.
Mikrochim Acta ; 189(4): 168, 2022 04 01.
Article in English | MEDLINE | ID: covidwho-1767504

ABSTRACT

The rapid spread of the novel human coronavirus 2019 (COVID-19) and its morbidity have created an urgent need for rapid and sensitive diagnostics. The real-time polymerase chain reaction is the gold standard for detecting the coronavirus in various types of biological specimens. However, this technique is time consuming, labor intensive, and expensive. Screen-printed electrodes (SPEs) can be used as point-of-care devices because of their low cost, sensitivity, selectivity, and ability to be miniaturized. The ability to detect the spike protein of COVID-19 in serum, urine, and saliva was developed using SPE aided by magnetic beads (MBs) and a portable potentiostat. The antibody-peroxidase-loaded MBs were the captured and catalytic units for the electrochemical assays. The MBs enable simple washing and homogenous deposition on the working electrode using a magnet. The assembly of the immunological MBs and the electrochemical system increases the measuring sensitivity and speed. The physical and electrochemical properties of the layer-by-layer modified MBs were systematically characterized. The performance of these immunosensors was evaluated using spike protein in the range 3.12-200 ng mL-1. We achieved a limit of detection of 0.20, 0.31, and 0.54 ng mL-1 in human saliva, urine, and serum, respectively. A facile electrochemical method to detect COVID-19 spike protein was developed for quick point-of-care testing.


Subject(s)
Biosensing Techniques , COVID-19 , Biosensing Techniques/methods , COVID-19/diagnosis , Electrodes , Humans , Immunoassay , Magnetic Phenomena , Point-of-Care Testing , Spike Glycoprotein, Coronavirus
6.
Am J Ophthalmol ; 235: 111-119, 2022 03.
Article in English | MEDLINE | ID: covidwho-1709798

ABSTRACT

PURPOSE: To analyze the outcomes of using an internal limiting membrane (ILM) flap and the conventional ILM peel technique for small- or medium-sized full-thickness macular hole (FTMH) repair. DESIGN: Retrospective, interventional case series. METHODS: Eyes with an FTMH ≤400 µm that underwent vitrectomy with a single-layer inverted ILM flap (flap group, 55 eyes) or an ILM peel (peel group, 62 eyes) were enrolled. Best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) measurements were obtained preoperatively and at 1, 3, 6, and 12 months postoperatively. RESULTS: Primary hole closure was achieved in 54 (98%) and 60 (97%) eyes in the flap and peel groups, respectively. The preoperative and postoperative 12-month BCVA values were comparable between the groups but were significantly better in the flap than in the peel group at 1 month (mean ± SD logMAR: 0.83 ± 0.43 vs 1.14 ± 0.50; P = .001), 3 months (0.58 ± 0.33 vs 0.82 ± 0.43; P = .002), and 6 months (0.56 ± 0.32 vs. 0.72 ± 0.48; P = .028). In the flap group, foveal gliosis was less common than in the peel group at 1 month (P = .030), and restored external limiting membrane and interdigitation zone was more common at 3 months (P = .046 and P < .001, respectively). CONCLUSIONS: The single-layer ILM flap and conventional ILM peel techniques both closed FTMHs and improved vision. ILM flaps were associated with better visual outcomes up to 6 months postoperatively and should be considered in FTMHs ≤400 µm.


Subject(s)
Retinal Perforations , Basement Membrane/surgery , Humans , Retinal Perforations/diagnosis , Retinal Perforations/surgery , Retrospective Studies , Tomography, Optical Coherence/methods , Visual Acuity , Vitrectomy/methods
7.
Taiwan J Ophthalmol ; 10(3): 153-166, 2020.
Article in English | MEDLINE | ID: covidwho-836327

ABSTRACT

The coronavirus disease 2019 (COVID 19) pandemic has presented major challenges to ophthalmologists. Reports have shown that ocular manifestations can be the first presenting symptoms of COVID 19 infection and conjunctiva may be a portal of entry for the severe acute respiratory syndrome (SARS) associated coronavirus 2 (SARS CoV 2). The purpose of this article is to provide general guidance for ophthalmologists to understand the prevalence of ocular presentation in COVID 19 patients and to reduce the risk of transmission during practice. Relevant studies published in the period of November 1, 2019, and July 15, 2020, regarding ocular manifestations of COVID 19 and detection of SARS CoV 2 in the eye were included in this systematic review and meta analysis. The pooled prevalence of the ocular manifestations has been estimated at 7% (95% confidence interval [CI]: 0.03-0.10) among COVID 19 patients. The pooled detection rate of SARS CoV 2 from conjunctiva was low (1%, 95% CI: 0.00-0.03). Conjunctival symptoms were the most common ocular manifestations in COVID 19, but the positive detection rate of the SARS CoV 2 virus by reverse transcription-polymerase chain reaction of conjunctival tears or secretions remained low. No study has shown a definite transmission of COVID 19 through ocular mucosa or secretions. In summary, ocular manifestations in COVID 19 patients commonly comprise ocular surface symptoms. Although a low prevalence of ocular symptoms was encountered among patients infected by SARS CoV 2, it is imperative for all ophthalmologists to understand the full spectrum of COVID 19 symptoms or signs including those of the eyes as well as to adopt appropriate protective measures during clinical practice.

8.
Taiwan J Ophthalmol ; 10(2): 80-86, 2020.
Article in English | MEDLINE | ID: covidwho-738422

ABSTRACT

PURPOSE: Although Taiwan was one of the first countries to develop coronavirus disease 2019 (COVID-19), with effective antiepidemic measures, Taiwan has effectively controlled the spread of the disease. The purpose of this article is to provide useful safety strategies for ophthalmologists in daily practice during the COVID-19 pandemic. MATERIALS AND METHODS: Infection control strategies in the hospital and Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou, are discussed. RESULTS: Ophthalmologists are at high risk of contracting COVID-19 infection, as they have close contact with patients during ocular examinations, and are also facing high patient volume in outpatient clinics as well as emergency consultations. Furthermore, ocular symptoms, such as conjunctivitis, may be the presenting signs of COVID-19 infection. We provide our strategies, which include hospital's gate control with triage station, patient volume control, proper personal protective equipment, and consultation with telemedicine technology, to decrease the risk of cross-infection between medical staffs and patients. CONCLUSION: To achieve the goal of preventing viral spread and maximizing patient and medical staffs' safety, besides providing proper protective equipment, it is also crucial for staffs and patients to strictly follow antiepidemic measures. We hope that our experience can help ophthalmologists and health-care workers to have a safer working environment when facing COVID-19 pandemic.

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