Díaz-Álvarez EA^1,2, AP Rojas-Cortés^1,2, E de la Barrera¹

Phyton-International Journal of Experimental Botany, Vol.86, pp. 278-281, 2017, DOI:10.32604/phyton.2017.86.278

Abstract The epiphytic bromeliad Tillandsia makoyana was studied to assess the contribution of the environmental factors, water, temperature, and light, to the expression of the Crassulacean acid metabolism. In particular, nocturnal titratable acidity accumulation and maximum leaf temperature were measured in response to watering and incident light. Plants that were watered and exposed to direct sunlight had the highest nocturnal accumulation of titratable acidity (25.52 ± 0.34 H⁺/m²), while those without irrigation and shaded showed a 59% reduction in their titratable acidity. Our results illustrated a rapid response of the photosynthetic activity to water availability in Tillandsia makoyana, a native species… More >

González-Franco AC¹, L Robles-Hernández¹, JL Strap²

Phyton-International Journal of Experimental Botany, Vol.86, pp. 14-27, 2017, DOI:10.32604/phyton.2017.86.014

Abstract The Streptomyces genus comprises a large and diverse group of bacteria, many of which are commercially exploited for the production of antibiotics and lytic enzymes. The thermophilic species are less studied than the predominant mesophilic species. However, the first ones are a potential source of thermostable bioactive products and enzymes with novel properties. In this study, two selected thermophilic streptomycetes were identified and their chitinolytic activities were evaluated. The identification of these two isolates was performed by microscopic morphology, partial 16S rDNA sequences, and its phylogenetic analysis. To study the chitinolytic activities of these isolates, the effects of colloidal chitin… More >

Frederick H. Silver^1,*, Ruchit G. Shah², Dominick Benedetto³

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 73-73, 2019, DOI:10.32604/mcb.2019.08150

Abstract Previous literature reports suggest that tissue stiffness is a predictor of cancer and metastatic behavior of lesions. We have used optical coherence tomography and vibrational analysis (VOCT) to characterize normal skin, scar, a verrucous carcinoma (a squamous cell carcinoma subtype), a basal cell carcinoma and benign skin lesions non-invasively and non-destructively. The results suggest that epidermal thickening and increased keratin and basal cell production occur in malignant lesions and lead to increases in surface hills and valleys as well as subsequent increases in epidermal stiffness values. Increased stiffness of the epidermis is a result of increased keratin and basal cell… More >

Caining Zhang¹, Huaguang Li², Xiaoya Guo³, David Molony⁴, Xiaopeng Guo², Habib Samady⁴, Don P. Giddens^4,5, Lambros Athanasiou⁶, Rencan Nie^2,*, Jinde Cao^3,*, Dalin Tang^1,*,7

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 31-31, 2019, DOI:10.32604/mcb.2019.06983

Abstract Cardiovascular diseases are closely associated with deteriorating atherosclerotic plaques. Optical coherence tomography (OCT) is a recently developed intravascular imaging technique with high resolution approximately 10 microns and could provide accurate quantification of coronary plaque morphology. However, tissue segmentation of OCT images in clinic is still mainly performed manually by physicians which is time consuming and subjective. To overcome these limitations, two automatic segmentation methods for intracoronary OCT image based on support vector machine (SVM) and convolutional neural network (CNN) were performed to identify the plaque region and characterize plaque components. In vivo IVUS and OCT coronary plaque data from 5… More >

Rui Lv¹, Liang Wang¹, Dalin Tang^1,*,2

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 27-28, 2019, DOI:10.32604/mcb.2019.06829

Abstract Medical imaging and image-based computational modeling have been used by many researchers in recent years to quantify atherosclerotic plaque morphological and biomechanical characteristics and predict the coronary plaque growth and rupture processes. However, it has been hard to validate model predictions due to imaging resolution limitation, lack of clinical events and plaque rupture data. This article reviews recent advances in coronary plaque research over the past decade, including medical imaging techniques represented by intravascular ultrasound (IVUS) and optical coherence tomography (OCT), computational modeling and their applications in plaque progression and vulnerability analyses and predictions. The clinical application and future development… More >

Liang Wang¹, Haibo Jia², Luping He², Rui Lv¹, Xiaoya Guo³, Chun Yang^4,5, Don P. Giddens^6,7, Habib Samady⁶, Akiko Maehara⁸, Gary S. Mintz⁸, Dalin Tang^1,*,5

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 23-24, 2019, DOI:10.32604/mcb.2019.07522

Abstract Plaque erosion, one of the primary causes for coronary thrombosis, is responsible for about one third of the patients with acute coronary syndrome (ACS) [1]. Histological studies characterized the eroded plaque as a plaque with following morphological features: 1) plaque intima having direct contact with intraluminal thrombus due to the absence of endothelium or endothelial injury; 2) without rupture in the fibrous cap; 3) abundance of proteoglycans and smooth muscle cells on the luminal surface under the thrombus [2]. These characteristics has been applied in in vivo diagnosis of plaque erosion using optical coherence tomography (OCT) imaging technology and specific… More >

Caining Zhang¹, Xiaoya Guo², Dalin Tang^1,3,*, David Molony⁴, Chun Yang³, Habib Samady⁴, Jie Zheng⁵, Gary S. Mintz⁶, Akiko Maehara⁶, Mitsuaki Matsumura⁶, Don P. Giddens^4,7

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 79-80, 2019, DOI:10.32604/mcb.2019.05747

Abstract Cardiovascular diseases are closely associated with sudden rupture of atherosclerotic plaques. Previous image modalities such as magnetic resonance imaging (MRI) and intravascular ultrasound (IVUS) were unable to identify vulnerable plaques due to their limited resolution. Optical coherence tomography (OCT) is an advanced intravascular imaging technique developed in recent years which has high resolution approximately 10 microns and could provide more accurate morphology of coronary plaque. In particular, it is now possible to identify plaques with fibrous cap thickness <65 μm, an accepted threshold value for vulnerable plaques. However, the current segmentation of OCT images are still performed manually by physicians… More >

Xiaoya Guo¹, Dalin Tang^1,2,*, David Molony³, Chun Yang², Habib Samady³, Jie Zheng⁴, Gary S. Mintz⁵, Akiko Maehara⁵, Jian Zhu⁶, Genshan Ma⁶, Mitsuaki Matsumura⁵, Don P. Giddens^3,7

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 75-76, 2019, DOI:10.32604/mcb.2019.05743

Abstract Atherosclerotic plaque progression is generally considered to be closely associated with morphological and mechanical factors. Plaque morphological information on intravascular ultrasound (IVUS) and optical coherence tomography (OCT) images could complement each other and provide for more accurate plaque morphology. Fluid-structure interaction (FSI) models combining IVUS and OCT were constructed to obtain accurate plaque stress/strain and flow shear stress data for analysis. Accuracy and completeness of imaging and advanced modeling lead to accurate plaque progression predictions.
In vivo IVUS and OCT coronary plaque data at baseline and follow-up were acquired from left circumflex coronary and right coronary artery of one… More >

Ju Huang¹, Cuiru Sun^1,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 67-68, 2019, DOI:10.32604/mcb.2019.05738

Abstract Intravascular optical coherence tomography (OCT) has the characteristics of high resolution and fast imaging speed. Continuous images of the same section of the same vessel can reflect the deformation characteristics of the vessel wall under different blood pressure. Digital image processing may be used to segment various structures on the vascular wall and extract the deformation incorporating with biomechanical analysis. Image filtering plays a very important role in image processing. Median filter was used to filter salt and pepper noise in OCT images. Fuzzy function gray processing method was used to suppress irrelevant information and improve image clarity. Dividing point… More >

Junjie Jia¹, Cuiru Sun^1,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 61-64, 2019, DOI:10.32604/mcb.2019.05736

Abstract Intravascular optical coherence tomography (IVOCT) has been employed to clinical coronary imaging for several years. But the influence of flushing and OCT catheter to the blood vessel biomechanical properties have not been studied. In this paper, IVOCT imaging is integrated with the fluid-structure interaction (FSI) simulation to study the blood flow velocity and the stress distribution of a porcine carotid artery during IVOCT imaging. 3D geometric model is built based on the in vivo OCT images, and a hyperelastic model is employed for the material properties of the vascular wall. The blood flow profile and wall stress distributions under various… More >