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1.
Int Wound J ; 21(4): e14565, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38146127

RESUMO

Chronic wounds contribute to significant healthcare and economic burden worldwide. Wound assessment remains challenging given its complex and dynamic nature. The use of artificial intelligence (AI) and machine learning methods in wound analysis is promising. Explainable modelling can help its integration and acceptance in healthcare systems. We aim to develop an explainable AI model for analysing vascular wound images among an Asian population. Two thousand nine hundred and fifty-seven wound images from a vascular wound image registry from a tertiary institution in Singapore were utilized. The dataset was split into training, validation and test sets. Wound images were classified into four types (neuroischaemic ulcer [NIU], surgical site infections [SSI], venous leg ulcers [VLU], pressure ulcer [PU]), measured with automatic estimation of width, length and depth and segmented into 18 wound and peri-wound features. Data pre-processing was performed using oversampling and augmentation techniques. Convolutional and deep learning models were utilized for model development. The model was evaluated with accuracy, F1 score and receiver operating characteristic (ROC) curves. Explainability methods were used to interpret AI decision reasoning. A web browser application was developed to demonstrate results of the wound AI model with explainability. After development, the model was tested on additional 15 476 unlabelled images to evaluate effectiveness. After the development on the training and validation dataset, the model performance on unseen labelled images in the test set achieved an AUROC of 0.99 for wound classification with mean accuracy of 95.9%. For wound measurements, the model achieved AUROC of 0.97 with mean accuracy of 85.0% for depth classification, and AUROC of 0.92 with mean accuracy of 87.1% for width and length determination. For wound segmentation, an AUROC of 0.95 and mean accuracy of 87.8% was achieved. Testing on unlabelled images, the model confidence score for wound classification was 82.8% with an explainability score of 60.6%. Confidence score was 87.6% for depth classification with 68.0% explainability score, while width and length measurement obtained 93.0% accuracy score with 76.6% explainability. Confidence score for wound segmentation was 83.9%, while explainability was 72.1%. Using explainable AI models, we have developed an algorithm and application for analysis of vascular wound images from an Asian population with accuracy and explainability. With further development, it can be utilized as a clinical decision support system and integrated into existing healthcare electronic systems.


Assuntos
Algoritmos , Inteligência Artificial , Humanos , Software , Aprendizado de Máquina , Instalações de Saúde
2.
Eur J Immunol ; 52(5): 737-752, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35245389

RESUMO

Resident memory T lymphocytes (TRM ) of epithelial tissues and the Bm protect their host tissue. To what extent these cells are mobilized and contribute to systemic immune reactions is less clear. Here, we show that in secondary immune reactions to the measles-mumps-rubella (MMR) vaccine, CD4+ TRM are mobilized into the blood within 16 to 48 h after immunization in humans. This mobilization of TRM is cognate: TRM recognizing other antigens are not mobilized, unless they cross-react with the vaccine. We also demonstrate through methylome analyses that TRM are mobilized from the Bm. These mobilized cells make significant contribution to the systemic immune reaction, as evidenced by their T-cell receptor Vß clonotypes represented among the newly generated circulating memory T-cells, 14 days after vaccination. Thus, TRM of the Bm confer not only local, but also systemic immune memory.


Assuntos
Memória Imunológica , Vacinas , Medula Óssea , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Humanos
3.
Int Wound J ; 20(3): 751-760, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36787270

RESUMO

Chronic wounds are associated with significant clinical, economic and quality-of-life burden. Despite the variety of wound imaging systems available in the market for wound assessment and surveillance, few are clinically validated among patients of Asian ethnicity. We aimed to clinically validate the accuracy of a smartphone wound application (Tissue Analytics [TA], Net Health Systems Inc, Florida, USA), versus conventional wound measurements (visual approximation and paper rulers), in patients of Asian ethnicity with venous leg ulcers (VLU). A prospective cohort study of patients presenting with VLU to a specialist wound nurse clinic over a 5-week duration was conducted. Each patient received seven wound measurements: one by a trained wound nurse clinician, and three separate wound measurements using TA on each of the iOS and Android operating systems. Inter-rater and intra-rater reliability between clinical and TA-based measurements were analysed using intra-class correlation statistics, with values of <0.5, 0.5 to 0.75, 0.75 to 0.9, and >0.9 indicating poor, moderate, good and excellent reliability, respectively. 82 patients (51% males), with a mean age at 65.8 years, completed the 5-week study duration. 25 (30%) had underlying diabetes mellitus. Chinese, Malay and Indian ethnicity comprised 68%, 12% and 11%, respectively. The VLU healed in 26 (32%) of patients within the study period. In total, 358 wound episodes with 2334 wound images were analysed. Inter-rater reliability for length, width and area between wound nurse measurements and TA application measurements was good (range 0.799-0.919, P < 0.001). Separate measurements of intra-rater reliability for length, width and area within the iOS or Android systems were excellent (range 0.967-0.985 and range 0.977-0.984 respectively, P < 0.001). Inter-rater reliability between TA used on the iOS and Android systems was also excellent (0.987-0.989, P < 0.001). Tissue Analytics, a smartphone wound application, is a useful adjunct for wound assessment and surveillance in VLU patients of Asian ethnicity.


Assuntos
Aplicativos Móveis , Úlcera Varicosa , Masculino , Humanos , Idoso , Feminino , Estudos Prospectivos , Smartphone , Reprodutibilidade dos Testes , Úlcera Varicosa/diagnóstico
4.
Int Wound J ; 19(2): 436-446, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34121320

RESUMO

Chronic venous insufficiency is a chronic disease of the venous system with a prevalence of 25% to 40% in females and 10% to 20% in males. Venous leg ulcers (VLUs) result from venous insufficiency. VLUs have a prevalence of 0.18% to 1% with a 1-year recurrence of 25% to 50%, bearing significant socioeconomic burden. It is therefore important for regular assessment and monitoring of VLUs to prevent worsening. Our study aims to assess the intra- and inter-rater reliability of a machine learning-based handheld 3-dimensional infrared wound imaging device (WoundAide [WA] imaging system, Konica Minolta Inc, Tokyo, Japan) compared with traditional measurements by trained wound nurse. This is a prospective cross-sectional study on 52 patients with VLUs from September 2019 to January 2021 using three WA imaging systems. Baseline patient profile and clinical demographics were collected. Basic wound parameters (length, width and area) were collected for both traditional measurements and measurements taken by the WA imaging systems. Intra- and inter-rater reliability was analysed using intra-class correlation statistics. A total of 222 wound images from 52 patients were assessed. There is excellent intra-rater reliability of the WA imaging system on three different image captures of the same wound (intra-rater reliability ranging 0.978-0.992). In addition, there is excellent inter-rater reliability between the three WA imaging systems for length (0.987), width (0.990) and area (0.995). Good inter-rater reliability for length and width (range 0.875-0.900) and excellent inter-rater reliability (range 0.932-0.950) were obtained between wound nurse measurement and each of the WA imaging system. In conclusion, high intra- and inter-rater reliability was obtained for the WA imaging systems. We also obtained high inter-rater reliability of WA measurements against traditional wound measurement. The WA imaging system is a useful clinical adjunct in the monitoring of VLU wound documentation.


Assuntos
Úlcera Varicosa , Estudos Transversais , Feminino , Humanos , Aprendizado de Máquina , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Úlcera Varicosa/diagnóstico por imagem
5.
Int Wound J ; 19(4): 765-773, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34363329

RESUMO

Present guidelines recommend a multidisciplinary team (MDT) approach to diabetic foot ulcer (DFU) care, but relevant data from Asia are lacking. We aim to evaluate the clinical and economic outcomes of an MDT approach in a lower extremity amputation prevention programme (LEAPP) for DFU care in an Asian population. We performed a case-control study of 84 patients with DFU between January 2017 and October 2017 (retrospective control) vs 117 patients with DFU between December 2017 and July 2018 (prospective LEAPP cohort). Comparing the clinical outcomes between the retrospective cohort and the LEAPP cohort, there was a significant decrease in mean time from referral to index clinic visit (38.6 vs 9.5 days, P < .001), increase in outpatient podiatry follow-up (33% vs 76%, P < .001), decrease in 1-year minor amputation rate (14% vs 3%, P = .007), and decrease in 1-year major amputation rate (9% vs 3%, P = .05). Simulation of cost avoidance demonstrated an annualised cost avoidance of USD $1.86m (SGD $2.5m) for patients within the LEAPP cohort. In conclusion, similar to the data from Western societies, an MDT approach in an Asian population, via a LEAPP for patients with DFU, demonstrated a significant reduction in minor and major amputation rates, with annualised cost avoidance of USD $1.86m.


Assuntos
Diabetes Mellitus , Pé Diabético , Úlcera do Pé , Amputação Cirúrgica , Estudos de Casos e Controles , Pé Diabético/prevenção & controle , Pé Diabético/cirurgia , Humanos , Extremidade Inferior , Equipe de Assistência ao Paciente , Estudos Prospectivos , Estudos Retrospectivos
7.
Biotechnol Lett ; 39(11): 1747-1755, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28762033

RESUMO

OBJECTIVES: To carry out mass propagation of superior plants to improve agricultural and silvicultural production though advancements in plant cell totipotency, or the ability of differentiated somatic plant cells to regenerate an entire plant. RESULTS: The first demonstration of a titratable control over somatic embryo formation in a commercially relevant plant, Theobroma cacao (Chocolate tree), was achieved using a dexamethasone activatable chimeric transcription factor. This four-fold enhancement in embryo production rate utilized a glucocorticoid receptor fused to an embryogenic transcription factor LEAFY COTYLEDON 2. Where previous T. cacao somatic embryogenesis has been restricted to dissected flower parts, this construct confers an unprecedented embryogenic potential to leaves. CONCLUSIONS: Activatable chimeric transcription factors provide a means for elucidating the regulatory cascade associated with plant somatic embryogenesis towards improving its use for somatic regeneration of transgenics and plant propagation.


Assuntos
Cacau/embriologia , Dexametasona/farmacologia , Receptores de Glucocorticoides/genética , Fatores de Transcrição/genética , Cacau/efeitos dos fármacos , Ativação Enzimática , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Técnicas de Embriogênese Somática de Plantas , Plantas Geneticamente Modificadas , Receptores de Glucocorticoides/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição/metabolismo
8.
J Vasc Surg Venous Lymphat Disord ; 11(5): 954-963, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37209840

RESUMO

OBJECTIVE: Venous leg ulcers (VLUs) are both chronic and recurrent. The treatment of such ulcers often require multiple outpatient visits and dressing changes. Several reports on the costs of treating such VLUs have been reported in the west. We prospectively evaluated the clinical and economic burden of VLUs in a population of Asian patients in the tropics. METHODS: Patients from a prospective two-center study conducted at two tertiary hospitals in Singapore, as a part of the Wound Care Innovation in the Tropics program, between August 2018 and September 2021 were recruited. The patients were followed up for 12 weeks (visit 1 to visit 12), until index ulcer healing, death, or lost to follow-up (whichever came first). These patients were then followed up 12 weeks later to determine the longer term outcome of the wound (healed, recurrence, remained unhealed). The itemized costs derived from the medical service were retrieved from the relevant departments of the study sites. The patients' health-related quality of life was assessed at baseline and the last visit of the 12-week follow-up period (or until index ulcer healing), using the official Singapore version of the EuroQol five-dimension-5L questionnaire, which also includes a visual analog scale (EQ-VAS). RESULTS: A total of 116 patients were enrolled; 63% were men, and the mean patient age was 64.7 years. Of the 116 patients, 85 (73%) had a healed ulcer at 24 weeks (mean duration to ulcer healing, 49 days), and 11 (12.9%) had experienced ulcer recurrence within the study period. Within the 6-month follow-up period, the mean direct healthcare cost per patient was USD$1998. The patients with healed ulcers had significantly lower costs per patient compared with those with unhealed ulcers (USD$1713 vs USD$2780). Regarding health-related quality of life, 71% of the patients had a lower quality of life at baseline, which had improved at 12 weeks of follow-up, with only 58% of the patients reported to have a lower quality of life. Also, the patients with healed ulcers scored higher for both utilities (societal preference weights) and EQ-VAS at follow-up (P < .001). In contrast, patients with unhealed ulcers only scored higher EQ-VAS at follow-up (P = .003). CONCLUSIONS: The findings from this exploratory study provide information on the clinical, quality of life, and economic burden of VLUs in an Asian population and suggest the importance of healing VLUs to reduce the effects on patients. The present study provides data as a basis for economic evaluation as a consideration for the treatment of VLUs.


Assuntos
Úlcera da Perna , Úlcera Varicosa , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Estudos Prospectivos , Úlcera , Qualidade de Vida , Estresse Financeiro , Úlcera Varicosa/terapia , Úlcera Varicosa/tratamento farmacológico , Úlcera da Perna/terapia
9.
Neuron ; 57(2): 232-47, 2008 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-18215621

RESUMO

The molecular mechanisms controlling the development of distinct subtypes of neocortical projection neurons, and CNS neuronal diversity more broadly, are only now emerging. We report that the transcription factor SOX5 controls the sequential generation of distinct corticofugal neuron subtypes by preventing premature emergence of normally later-born corticofugal neurons. SOX5 loss-of-function causes striking overlap of the identities of the three principal sequentially born corticofugal neuron subtypes: subplate neurons, corticothalamic neurons, and subcerebral projection neurons. In Sox5(-/-) cortex, subplate neurons aberrantly develop molecular hallmarks and connectivity of subcerebral projection neurons; corticothalamic neurons are imprecisely differentiated, while differentiation of subcerebral projection neurons is accelerated. Gain-of-function analysis reinforces the critical role of SOX5 in controlling the sequential generation of corticofugal neurons--SOX5 overexpression at late stages of corticogenesis causes re-emergence of neurons with corticofugal features. These data indicate that SOX5 controls the timing of critical fate decisions during corticofugal neuron production and thus subtype-specific differentiation and neocortical neuron diversity.


Assuntos
Córtex Cerebral/citologia , Proteínas de Ligação a DNA/fisiologia , Neurônios/classificação , Neurônios/fisiologia , Proteínas Nucleares/fisiologia , Proteínas Repressoras/fisiologia , Tálamo/citologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Animais Recém-Nascidos , Bromodesoxiuridina/metabolismo , Contagem de Células/métodos , Diferenciação Celular , Córtex Cerebral/embriologia , Córtex Cerebral/crescimento & desenvolvimento , Proteínas de Ligação a DNA/deficiência , Eletroporação/métodos , Embrião de Mamíferos , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , Vias Neurais/citologia , Proteínas Nucleares/deficiência , Fatores de Transcrição SOXD , Estilbamidinas/metabolismo , Tálamo/embriologia , Tálamo/crescimento & desenvolvimento , Proteínas Supressoras de Tumor/deficiência
10.
Nucleic Acids Res ; 32(4): 1363-71, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14985472

RESUMO

The ARB (from Latin arbor, tree) project was initiated almost 10 years ago. The ARB program package comprises a variety of directly interacting software tools for sequence database maintenance and analysis which are controlled by a common graphical user interface. Although it was initially designed for ribosomal RNA data, it can be used for any nucleic and amino acid sequence data as well. A central database contains processed (aligned) primary structure data. Any additional descriptive data can be stored in database fields assigned to the individual sequences or linked via local or worldwide networks. A phylogenetic tree visualized in the main window can be used for data access and visualization. The package comprises additional tools for data import and export, sequence alignment, primary and secondary structure editing, profile and filter calculation, phylogenetic analyses, specific hybridization probe design and evaluation and other components for data analysis. Currently, the package is used by numerous working groups worldwide.


Assuntos
Análise de Sequência de DNA , Análise de Sequência de Proteína , Análise de Sequência de RNA , Software , Apresentação de Dados , Bases de Dados Genéticas , Internet , Filogenia , Alinhamento de Sequência , Fatores de Tempo
11.
Talanta ; 97: 9-15, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22841041

RESUMO

In order to maximize peak capacity and detection sensitivity of fast gas chromatography (GC) separations, it is necessary to minimize band broadening, and in particular due to injection since this is often a major contributor. A high-speed cryo-focusing injection (HSCFI) system was constructed to first cryogenically focus analyte compounds in a 6 cm long section of metal MXT column, and second, reinject the focused analytes by rapidly resistively heating the metal column via an in-house built electronic circuit. Since the cryogenically cooled section of column is small (∼750 nl) and the direct resistive heating is fast (∼6000 °C/s), HSCFI is demonstrated to produce an analyte peak with a 6.3 ms width at half height, w(1/2). This was achieved using a 1m long column with a 180 µm inner diameter (i.d.) operated at an absolute head pressure of 55 psi and an oven temperature of 60 °C, with a 10 V pulse applied to the metal column for 50 ms. HSCFI was also used to demonstrate the head space sampling and fast GC analysis of an aqueous solution containing six test analytes (acetone, methanol, ethanol, toluene, chlorobenzene, pentanol). Using Henry's law constants for each of the analytes, injected mass limits of detection (LODs) were typically in the low pg levels (e.g., 1.2 pg for acetone) for the high speed separation. Finally, to demonstrate the use of HSCFI with a complex sample, a gasoline was separated using a 20 m × 100 µm i.d. column and the stock GC oven for temperature programming, which provided a separation time of 200 s and an average peak width at the base of 440 ms resulting in a total peak capacity of 460 peaks (at unit resolution).

12.
Development ; 131(23): 5991-6000, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15539493

RESUMO

Directional cues guide growth cones. While molecules like UNC-6/netrin direct migrations along the dorsoventral axis of many organisms, it is unclear how anteroposterior guidance is achieved. We describe a physical interaction between VAB-8, a protein both necessary and sufficient for posteriorly directed migrations in C. elegans, and UNC-51, a conserved serine/threonine kinase that functions generally in axon outgrowth. We show that both proteins function in the CAN neurons to direct their axons posteriorly. Expression in the CANs of peptides predicted to interfere with interactions between UNC-51 and both VAB-8 and UNC-14, a second protein that interacts physically with UNC-51, disrupts CAN axon outgrowth. We provide genetic evidence that VAB-8 functions in an UNC-51 pathway for posteriorly directed CAN axon guidance and show that VAB-8 and UNC-14 can be targets of UNC-51 kinase activity. Taken together, our results suggest that VAB-8 and UNC-14 are substrates that mediate the function of UNC-51 in axon outgrowth.


Assuntos
Axônios/fisiologia , Proteínas de Caenorhabditis elegans/fisiologia , Proteínas de Transporte/fisiologia , Neurônios/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Axônios/metabolismo , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Transporte/genética , Membrana Celular/metabolismo , Proliferação de Células , Proteínas do Citoesqueleto , DNA Complementar/metabolismo , Modelos Biológicos , Peptídeos/química , Fenótipo , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína , Interferência de RNA , Transfecção , Técnicas do Sistema de Duplo-Híbrido
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