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1.
PeerJ ; 12: e17553, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938609

RESUMEN

Background: White-rot fungi and bacteria communities are unique ecosystems with different types of symbiotic interactions occurring during wood decomposition, such as cooperation, mutualism, nutritional competition, and antagonism. The role of chitin-active lytic polysaccharide monooxygenases (LPMOs) in these symbiotic interactions is the subject of this study. Method: In this study, bioinformatics tools were used to analyze the sequence and structure of putative LPMOs mined by hidden Markov model (HMM) profiles from the bacterial metagenomic DNA database of collected humus samples around white-rot fungi in Cuc Phuong primary forest, Vietnam. Two genes encoding putative LPMOs were expressed in E. coli and purified for enzyme activity assay. Result: Thirty-one full-length proteins annotated as putative LPMOs according to HMM profiles were confirmed by amino acid sequence comparison. The comparison results showed that although the amino acid sequences of the proteins were very different, they shared nine conserved amino acids, including two histidine and one phenylalanine that characterize the H1-Hx-Yz motif of the active site of bacterial LPMOs. Structural analysis of these proteins revealed that they are multidomain proteins with different functions. Prediction of the catalytic domain 3-D structure of these putative LPMOs using Alphafold2 showed that their spatial structures were very similar in shape, although their protein sequences were very different. The results of testing the activity of proteins GL0247266 and GL0183513 show that they are chitin-active LPMOs. Prediction of the 3-D structures of these two LPMOs using Alphafold2 showed that GL0247266 had five functional domains, while GL0183513 had four functional domains, two of which that were similar to the GbpA_2 and GbpA_3 domains of protein GbpA of Vibrio cholerae bacteria. The GbpA_2 - GbpA_3 complex was also detected in 11 other proteins. Based on the structural characteristics of functional domains, it is possible to hypothesize the role of chitin-active GbpA-like LPMOs in the relationship between fungal and bacterial communities coexisting on decomposing trees in primary forests.


Asunto(s)
Oxigenasas de Función Mixta , Vietnam , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/metabolismo , Bosques , Quitina/metabolismo , Metagenómica , Metagenoma , Secuencia de Aminoácidos
2.
bioRxiv ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38798665

RESUMEN

Purpose: Two-photon microscopy (2PM) is an emerging clinical imaging modality with the potential to non-invasively assess tissue metabolism and morphology in high-resolution. This study aimed to assess the translational potential of 2PM for improved detection of high-grade cervical precancerous lesions. Experimental Design: 2P images attributed to reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and oxidized flavoproteins (FP) were acquired from the full epithelial thickness of freshly excised human cervical tissue biopsies (N = 62). Fifteen biopsies harbored high-grade squamous intraepithelial lesions (HSILs), 14 biopsies harbored low-grade SILs (LSILs), and 33 biopsies were benign. Quadratic discriminant analysis (QDA) leveraged morphological and metabolic functional metrics extracted from these images to predict the presence of HSILs. We performed gene set enrichment analysis (GSEA) using datasets available on the Gene Expression Omnibus (GEO) to validate the presence of metabolic reprogramming in HSILs. Results: Integrating metabolic and morphological 2P-derived metrics from finely sampled, full-thickness epithelia achieved a high 90.8 ± 6.1% sensitivity and 72.3 ± 11.3% specificity of HSIL detection. Notably, sensitivity (91.4 ± 12.0%) and specificity (77.5 ± 12.6%) were maintained when utilizing metrics from only two images at 12- and 72-µm from the tissue surface. Upregulation of glycolysis, fatty acid metabolism, and oxidative phosphorylation in HSIL tissues validated the metabolic reprogramming captured by 2P biomarkers. Conclusion: Label-free 2P images from as few as two epithelial depths enable rapid and robust HSIL detection through the quantitative characterization of metabolic and morphological reprogramming, underscoring the potential of this tool for clinical evaluation of cervical precancers.

3.
J Biomed Opt ; 28(12): 126006, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38144697

RESUMEN

Significance: Label-free, two-photon excited fluorescence (TPEF) imaging captures morphological and functional metabolic tissue changes and enables enhanced understanding of numerous diseases. However, noise and other artifacts present in these images severely complicate the extraction of biologically useful information. Aim: We aim to employ deep neural architectures in the synthesis of a multiscale denoising algorithm optimized for restoring metrics of metabolic activity from low-signal-to-noise ratio (SNR), TPEF images. Approach: TPEF images of reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavoproteins (FAD) from freshly excised human cervical tissues are used to assess the impact of various denoising models, preprocessing methods, and data on metrics of image quality and the recovery of six metrics of metabolic function from the images relative to ground truth images. Results: Optimized recovery of the redox ratio and mitochondrial organization is achieved using a novel algorithm based on deep denoising in the wavelet transform domain. This algorithm also leads to significant improvements in peak-SNR (PSNR) and structural similarity index measure (SSIM) for all images. Interestingly, other models yield even higher PSNR and SSIM improvements, but they are not optimal for recovery of metabolic function metrics. Conclusions: Denoising algorithms can recover diagnostically useful information from low SNR label-free TPEF images and will be useful for the clinical translation of such imaging.


Asunto(s)
Aprendizaje Profundo , Humanos , Diagnóstico por Imagen , Relación Señal-Ruido , Análisis de Ondículas , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos
4.
bioRxiv ; 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37333366

RESUMEN

Label-free, two-photon imaging captures morphological and functional metabolic tissue changes and enables enhanced understanding of numerous diseases. However, this modality suffers from low signal arising from limitations imposed by the maximum permissible dose of illumination and the need for rapid image acquisition to avoid motion artifacts. Recently, deep learning methods have been developed to facilitate the extraction of quantitative information from such images. Here, we employ deep neural architectures in the synthesis of a multiscale denoising algorithm optimized for restoring metrics of metabolic activity from low-SNR, two-photon images. Two-photon excited fluorescence (TPEF) images of reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavoproteins (FAD) from freshly excised human cervical tissues are used. We assess the impact of the specific denoising model, loss function, data transformation, and training dataset on established metrics of image restoration when comparing denoised single frame images with corresponding six frame averages, considered as the ground truth. We further assess the restoration accuracy of six metrics of metabolic function from the denoised images relative to ground truth images. Using a novel algorithm based on deep denoising in the wavelet transform domain, we demonstrate optimal recovery of metabolic function metrics. Our results highlight the promise of denoising algorithms to recover diagnostically useful information from low SNR label-free two-photon images and their potential importance in the clinical translation of such imaging.

5.
J Pediatr Adolesc Gynecol ; 35(3): 249-259, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34999228

RESUMEN

In 2015, the Resident Education Committee of the North American Society for Pediatric and Adolescent Gynecology published the Long Curriculum in Resident Education to provide educators with a comprehensive document to be used in postgraduate medical education. The original curriculum was designed to meet the resident learning objectives for the Council on Resident Education in Obstetrics and Gynecology, the American Board of Pediatrics, and the Royal College of Physicians and Surgeons of Canada and to provide a more intensive, broader learning experience. The curriculum was updated in 2018. This Committee Document is the third updated version (3.0) of the Long Curriculum in Resident Education.


Asunto(s)
Medicina del Adolescente , Ginecología , Internado y Residencia , Obstetricia , Pediatría , Adolescente , Medicina del Adolescente/educación , Niño , Curriculum , Femenino , Ginecología/educación , Humanos , Obstetricia/educación , Pediatría/educación , Embarazo , Estados Unidos
6.
J Pediatr Adolesc Gynecol ; 34(3): 291-296, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33810968

RESUMEN

Exposure to pediatric and adolescent gynecology (PAG) varies across residency programs in obstetrics and gynecology, family medicine, and pediatrics, as well as fellowship programs in adolescent medicine. Nevertheless, these programs are responsible for training residents and fellows and providing opportunities within their programs to fulfill PAG learning objectives. To that end, the North American Society for Pediatric and Adolescent Gynecology has taken a leadership role in PAG education by creating and systematically updating the Short Curriculum. This curriculum outlines specific learning objectives that are central to PAG education and lists essential resources for learners' reference. This updated curriculum replaces the previous 2018 publication with added content, resources, and updated references.


Asunto(s)
Medicina del Adolescente/educación , Curriculum , Ginecología/educación , Internado y Residencia/métodos , Pediatría/educación , Adolescente , Niño , Femenino , Humanos , Estados Unidos
7.
Chemosphere ; 265: 129167, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33307502

RESUMEN

Actinoplanes sp. A1094 strain had been selected for its high production of acarbose from 20 different strains of Actinoplanes sp. can be found in wild. The content for glucosidase inhibitor of acarbose concentration was recorded at 1.12 g/L. The conducted analysis of 16S rRNA sequence of Actinoplanes sp. A1094 showed 99% similar identity to the corresponding sequence of Actinoplanes hulinensis. Acarbose was purified from Actinoplanes hulinensis 1094 with a yield of 8.48%, purity of 98% and further identified by LC/MS and NMR methods (C25H43NO18; m/z: 645.6 g/mol). The purified acarbose was used to evaluate the hypoglycemia in streptozotocin (STZ)-induced diabetic mice model. The purified acarbose reduced postprandial blood glucose level in comparison with Glucobay® as medication for control type 2 diabetes in a combination therapy. Notably, the outcomes of native acarbose on fasting blood glucose levels in mice resemble akin to the commercial product and the acarbose accumulating fermentation and metabolic engineering from the cell gene in which would reduce in production cost. Therefore, acarbose from Actinoplanes hulinensis 1094 could be potentially used to make products for the treatment of type II diabetes.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Acarbosa , Actinoplanes , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de Glicósido Hidrolasas/farmacología , Ratones , ARN Ribosómico 16S
8.
Cell Rep Med ; 1(2)2020 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-32577625

RESUMEN

While metabolic changes are considered a cancer hallmark, their assessment has not been incorporated in the detection of early or precancers, when treatment is most effective. Here, we demonstrate that metabolic changes are detected in freshly excised human cervical precancerous tissues using label-free, non-destructive imaging of the entire epithelium. The images rely on two-photon excited fluorescence from two metabolic co-enzymes, NAD(P)H and FAD, and have micron-level resolution, enabling sensitive assessments of the redox ratio and mitochondrial fragmentation, which yield metrics of metabolic function and heterogeneity. Simultaneous characterization of morphological features, such as the depth-dependent variation of the nuclear:cytoplasmic ratio, is demonstrated. Multi-parametric analysis combining several metabolic metrics with morphological ones enhances significantly the diagnostic accuracy of identifying high-grade squamous intraepithelial lesions. Our results motivate the translation of such functional metabolic imaging to in vivo studies, which may enable improved identification of cervical lesions, and other precancers, at the bedside.


Asunto(s)
Cuello del Útero/diagnóstico por imagen , Imagen Óptica/métodos , Lesiones Precancerosas/diagnóstico , Displasia del Cuello del Útero/diagnóstico , Neoplasias del Cuello Uterino/diagnóstico , Cuello del Útero/metabolismo , Cuello del Útero/patología , Epitelio/diagnóstico por imagen , Epitelio/metabolismo , Epitelio/patología , Femenino , Flavina-Adenina Dinucleótido/metabolismo , Humanos , Redes y Vías Metabólicas , Dinámicas Mitocondriales/fisiología , NAD/metabolismo , NADP/metabolismo , Lesiones Precancerosas/metabolismo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Coloración y Etiquetado
9.
J Pediatr Adolesc Gynecol ; 32(5): 469-480, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31301359

RESUMEN

In 2015 the Resident Education Committee published the Long Curriculum in Resident Education to provide educators with a comprehensive document to be used in post-graduate medical education. The original curriculum was designed to meet the resident learning objectives for CREOG, RCPSC and ABP and to provide a more intensive, broader learning experience. This Committee Document is an updated version of the 2015 Long Curriculum.


Asunto(s)
Curriculum , Ginecología/educación , Internado y Residencia/métodos , Obstetricia/educación , Pediatría/educación , Adolescente , Medicina del Adolescente/educación , Niño , Femenino , Humanos , Embarazo
10.
Int J Microbiol ; 2016: 7207818, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27795709

RESUMEN

Ham Yen orange (Citrus nobilis Lour) is the highly valuable commercial fruit of Vietnam. With the blooming of fruit production and farming area, this specialty crop is facing threats from several serious diseases; therefore the search for new effective biocontrollers is required to prevent the existing excessive use of fertilizers and plant protection chemicals. Endophytic actinomycetes are of great scientific interest due to their high potential of application in agriculture and pharmaceutical research. In this work, endophytic actinomycetes were isolated from a native orange species of Northeast mountainous province Tuyen Quang. Among 49 isolates obtained, the isolate TQR12-4 strongly inhibited test pathogens Colletotrichum truncatum, Geotrichum candidum, Fusarium oxysporum, and F. udum. This isolate gave comparatively high biomass yields on different substrates, for example, carboxy methyl cellulose, starch, protein, and chitin, within a wide range of temperature from 15 to 45°C and pH from 4 to 10. Sequence analysis of 16S rDNA gene showed that TQR12-4 shared 99% similarity to Streptomyces prasinopilosus; however, it slightly differed from the latter in spore morphology and hence was named as Streptomyces sp. TQR12-4. A thermostable antifungal substance of nonpeptide nature produced by Streptomyces sp. TQR12-4 had MIC against Fusarium udum of 100 µg/mL and 400 µg/mL respective to extract fractions X4 and X5.

11.
J AOAC Int ; 98(4): 902-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26268970

RESUMEN

A simple, sensitive, and rapid HPLC method was developed to analyze bakuchiol and two furocoumarins (psoralen and angelicin) simultaneously in bakuchiol extracts from Psoralea corylifolia seeds. The analysis was performed within 30 min on a phenyl-hexyl column using gradient elution with a mobile phase composed of water and methanol with UV detection at 260 nm for bakuchiol and 246 nm for psoralen and angelicin. The method was validated with respect to linearity (r2>0.99 for all components), accuracy (>95% for all components), and precision (<2% RSD for both interday and intraday). Sensitivity of impurity detection in the sample was achieved as low as 0.36 and 0.31 µg/mL for psoralen and angelicin, respectively. Therefore, the method is suitable for QC of P. corylifolia extracts and bakuchiol related samples.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Furocumarinas/análisis , Fenoles/análisis , Extractos Vegetales/análisis , Psoralea/química , Estabilidad de Medicamentos , Límite de Detección , Fenoles/química
12.
Int J Cancer ; 136(2): 322-32, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24862444

RESUMEN

Mitochondrial organization is often altered to accommodate cellular bioenergetic and biosynthetic demands. Changes in metabolism are a hallmark of a number of diseases, including cancer; however, the interdependence between mitochondrial metabolic function and organization is not well understood. Here, we present a noninvasive, automated and quantitative method to assess mitochondrial organization in three-dimensional (3D) tissues using exclusively endogenous two-photon excited fluorescence (TPEF) and show that mitochondrial organization reflects alterations in metabolic activities. Specifically, we examine the organization of mitochondria within live, engineered epithelial tissue equivalents that mimic normal and precancerous human squamous epithelial tissues. We identify unique patterns of mitochondrial organization in the different tissue models we examine, and we attribute these to differences in the metabolic profiles of these tissues. We find that mitochondria are clustered in tissues with high levels of glycolysis and are more highly networked in tissues where oxidative phosphorylation is more dominant. The most highly networked organization is observed within cells with high levels of glutamine consumption. Furthermore, we demonstrate that mitochondrial organization provides complementary information to traditional morphological hallmarks of cancer development, including variations in nuclear size. Finally, we present evidence that this automated quantitative analysis of endogenous TPEF images can identify differences in the mitochondrial organization of freshly excised normal and pre-cancerous human cervical tissue specimens. Thus, this method could be a promising new modality to assess the role of mitochondrial organization in the metabolic activity of 3D tissues and could be further developed to serve as an early cancer clinical diagnostic biomarker.


Asunto(s)
Biomarcadores/análisis , Carcinoma de Células Escamosas/patología , Células Epiteliales/patología , Mitocondrias/patología , Lesiones Precancerosas/patología , Neoplasias del Cuello Uterino/patología , Células Cultivadas , Femenino , Humanos , Imagenología Tridimensional , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Pronóstico
13.
J AOAC Int ; 92(3): 785-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19610368

RESUMEN

Teucrium chamaedrys (Gemander) has been reported as an adulterant of Scutellaria lateriflora (American skullcap) herbal preparations and is also known to be hepatotoxic. A quick and simple high-performance thin-layer chromatographic (HPTLC) method was developed for the detection of T. chamaedrys (Germander) in S. baicalensis (Chinese skullcap) extract, an ingredient of the proprietary blend product, Univestin. The HPTLC profile of T. chamaedrys was distinguished from that of S. baicalensis by its bright green fluorescence bands. This simple method can be completed in an hour for the quality control of Univestin and its raw material, S. baicalensis. The method is sensitive and can detect T. chamaedrys at levels as low as 0.5% (w/w).


Asunto(s)
Cromatografía en Capa Delgada/métodos , Contaminación de Medicamentos , Extractos Vegetales/análisis , Scutellaria baicalensis/química , Teucrium/química , Sensibilidad y Especificidad
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