Open Access Articles – A Sensitive Chromatographic Method for Hyaluronate Quantification Applied to Analyze the Desorption Behavior on Contact Lenses

Journal Name: Current Pharmaceutical Analysis

Author(s): Wan-Hsin Chang, Pei-Yi Liu, Yuan-Ting Jiang*, Yuan-Hao Howard Hsu*.

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Abstract:

Background: Sodium hyaluronate (NaHA) is generally supplemented in products related to contact lenses for increasing comfort during wearing. The quantity of sodium hyaluronate and the material of lenses affect the retention of sodium hyaluronate on the contact lenses.

Methods: We developed a convenient and sensitive but unconventional chromatographic method to quantify sodium hyaluronate and analyze its release behavior from contact lenses. The reverse-phase chromatography eluted sodium hyaluronate with high molecular masses in the shortest time and could separate salt and small compounds from sodium hyaluronate.

Results: This method could accurately quantify sodium hyaluronate with diverse molecular sizes. Because sodium hyaluronate was eluted in a narrow time frame, sensitivity was significantly enhanced, and the limit of detection of this method was 0.45 μg/mL. According to this quantitation method, the attached quantity of sodium hyaluronate is related to the water content of the material. Furthermore, a material test indicated that the release efficiency of sodium hyaluronate depends on the material of lenses. Nonionic Polymacon had a longer half-life in the sodium hyaluronate release curve than negative Methafilcon A and silicone hydrogel.

Conclusion: This hyaluronate quantification method is a fast, sensitive and accurate method, making it suitable for the in vitro hyaluronate research without further derivatization. To read out more, please visit: http://www.eurekaselect.com/170419/article

Open Access Articles | 3D Cascaded Convolutional Networks for Multi-vertebrae Segmentation

 

Journal Name: Current Medical Imaging
Formerly: Current Medical Imaging Reviews

 

Author(s): Liu Xia, Liu Xiao, Gan Quan, Wang Bo*.

 

 

 

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Abstract:

Background: Automatic approach to vertebrae segmentation from computed tomography (CT) images is very important in clinical applications. As the intricate appearance and variable architecture of vertebrae across the population, cognate constructions in close vicinity, pathology, and the interconnection between vertebrae and ribs, it is a challenge to propose a 3D automatic vertebrae CT image segmentation method.

Objective: The purpose of this study was to propose an automatic multi-vertebrae segmentation method for spinal CT images.

Methods: Firstly, CLAHE-Threshold-Expansion was preprocessed to improve image quality and reduce input voxel points. Then, 3D coarse segmentation fully convolutional network and cascaded finely segmentation convolutional neural network were used to complete multi-vertebrae segmentation and classification.

Results: The results of this paper were compared with the other methods on the same datasets. Experimental results demonstrated that the Dice similarity coefficient (DSC) in this paper is 94.84%, higher than the V-net and 3D U-net.

Conclusion: Method of this paper has certain advantages in automatically and accurately segmenting vertebrae regions of CT images. Due to the easy acquisition of spine CT images. It was proven to be more conducive to clinical application of treatment that uses our segmentation model to obtain vertebrae regions, combining with the subsequent 3D reconstruction and printing work. To read out more, please visit: http://www.eurekaselect.com/168045/article

Open Access Articles | Antitumor Activity of Cyclodextrin-based Supramolecular Platinum Prodrug In vitro and In vivo

Journal Name: Letters in Drug Design & Discovery

Author(s): Yu-Hui Zhang, Jie Wang, Siqintana Xin, Li-Juan Wang, Xianliang Sheng*.

 

 

 

 

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Abstract:

Background: Considering the limitations of cisplatin in clinical application, there is ongoing research to fabricate new platinum-containing prodrug which are highly effective to tumor cells and have low toxicity to normal cells.

Methods: In this study, a cyclodextrin-based supramolecular platinum prodrug that is 6,6’-ophenylenediseleno- bridged bis (β-cyclodextrin)s (CD) and its potassium tetrachloroplatinate(II) complex was reported. The cytotoxicity experiments were performed to evaluate the anticancer activities of supramolecular prodrug in vitro by means of MTT assay. The practical application of supramolecular prodrug in tumor treatment in vivo were evaluated using BALB/c nude mice model bearing Hela cancer cells.

Results: Compared with commercial anticancer drug cisplatin, the resultant cyclodextrin-based platinum prodrug exhibited comparative anticancer effect but with much lower toxicity side effects in vitro and in vivo.

Conclusion: The cyclodextrin-based supramolecular platinum prodrug displayed antitumor activity comparable to the commercial antitumor drug cisplatin but with lower side effects both in vitro and in vivo, implying that the two adjacent cyclodextrin cavities not merely act as desired solubilizer, but also endowed the prodrug with cell permeability through the interaction of cyclodextrin with phospholipids and cholesterol on cell membrane. To read out more, please visit: http://www.eurekaselect.com/172707/article

Open Access Articles | Tissue Distribution of Active Principles from Alpiniae Oxyphyllae Fructus Extract: An Experimental Study in Rats

 

Journal Name: Current Pharmaceutical Analysis

            Author(s): Qi Wen, Hai-Long Li, Shi-Ying Mai, Yin-Feng Tan*, Feng Chen*.

 

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Abstract:

Background: Alpiniae Oxyphyllae Fructus (Yizhi in Chinese) have been widely used as an herbal medicine for the treatment of diuresis, enuresis and diarrhea in China. Many studies have deciphered some potential underlying mechanisms for its anti-diarrheal effects. However, tissue distribution of Yizhi constituents is warranted because pharmacological receptors are frequently located in tissues. Moreover, it is also interesting to know about the potential correlation between behavior in drug distribution and the observed pharmacological response. The aim of this study is to investigate tissue distribution behaviors of Yizhi constituents after oral administration of Yizhi extract to rats, focusing on 10 active principles.

Methods: Twenty four male Sprague Dawley rats were given orally the Yizhi extract and fourteen tissue samples were collected after being killed by bleeding from the abdominal aorta under ether anesthesia at different time-points. The resulting tissues were excised and homogenized. Based on our previous reports, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used to quantify the target analytes, as well as phase II metabolites, in the various biosamples.

Results: Almost all the targeted Yizhi active principles and some glucuronidated metabolites were qualitatively measured in rat stomach, small intestine, large intestine, as well as liver. Nootkatone, yakuchinone A and tectochrysin were observed in the rat brain. In other rat tissues, these analytes had lower exposure or could not be detected. Consistently, quantitative analysis revealed that the Yizhi active principles dominantly distributed into gastrointestinal tissues followed by liver, the overall exposure levels ranking as follows: stomach > small intestine > large intestine > liver. Tissue concentrationtime profiles of the test active principles in rat stomach, small intestine, and large intestine were bimodal with two concentration peaks occurring at 0.5 and 4h after oral administration, respectively. The exposure levels in rat kidney and bladder were quite low.

Conclusion: The active principles of Yizhi were specially distributed into gastrointestinal tissues after oral administration of its ethanol extract to rats. The tissue distribution behaviors partly supported its anti-diarrheal effects from a pharmacokinetic opinion. This paper will be useful as the starting point for studying the pharmacological activities of this traditional herb. To read out more, please visit: http://www.eurekaselect.com/165218/article

Open Access Articles | An Integrated Computational Approach for Plant-Based Protein Tyrosine Phosphatase Non-Receptor Type 1 Inhibitors

 

Journal Name: Current Computer-Aided Drug Design

Author(s): Shabana Bibi, Katsumi Sakata*.

 

 

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Abstract:

Background: Protein tyrosine phosphatase non-receptor type 1 is a therapeutic target for the type 2 diabetes mellitus. According to the International Diabetes Federation 2015 report, one out of 11 adults suffers from diabetes mellitus globally.

Objective: Current anti-diabetic drugs can cause life-threatening side-effects. The present study proposes a pipeline for the development of effective and plant-derived anti-diabetic drugs that may be safer and better tolerated.

Methods: Plant-derived protein tyrosine phosphatase non-receptor type 1 inhibitors possessing antidiabetic activity less than 10µM were used as a training set. A common feature pharmacophore model was generated. Pharmacophore-based screening of plant-derived compounds of the ZINC database was conducted using ZINCpharmer. Screened hits were assessed to evaluate their drug-likeness, pharmacokinetics, detailed binding behavior, and aggregator possibility based on their physiochemical properties and chemical similarity with reported aggregators.

Results: Through virtual screening and in silico pharmacology protocol isosilybin (ZINC30731533) was identified as a lead compound with optimal properties. This compound can be recommended for laboratory tests and further analyses to confirm its activity as protein tyrosine phosphatase nonreceptor type 1 inhibitor.

Conclusion: The present study has identified plant-derived anti-diabetic virtual lead compound with the potential to inhibit protein tyrosine phosphatase non-receptor type 1, which may be helpful to enhance insulin production. This computer-aided study could facilitate the development of novel pharmacological inhibitors for diabetes treatment. To read out more, please visit: http://www.eurekaselect.com/151386/article

Open Access Articles | Synthesis and Modifications of Electron-withdrawing Groups Based on Multi-cyano Heterocyclics

Journal Name: Mini-Reviews in Organic Chemistry

Author(s): Guowei Deng, Qihui Wang, Min Yang, Bingke Li, Tao Han, Bo Chang, Xianghui Li, Xiaoling Zhang*, Zhonghui Li*.

 

 

Electron deficient compounds are extensively studied in the field of molecular materials. Compared to the simplest electron acceptors, multi-cyano heterocyclics performed excellent properties in electron-withdrawing ability, thermal stability, etc. This review provides a survey of the synthesis and modifications of two kinds of multi-cyano heterocyclics and their applications. To read out more, please visit: http://www.eurekaselect.com/161229/article

Open Access Articles | Recent Advances in Color and Whiteness Evaluations in Dentistry

 

Journal Name: Current Dentistry

 

Author(s): María M. Pérez*, Oscar E. Pecho, Razvan Ghinea, Rosa Pulgar, Alvaro Della Bona.

 

Background: The final goal of color measurement or shade specification in dentistry is the reproduction by prosthetic materials of all important appearance characteristics of natural oral structures. The application of color science in dentistry is an objective way to measure and evaluate such structures and dental materials in clinical practice and dental research.

Methods: Literature on color science was reviewed to present new metrics to evaluate color differences of dental materials and dental structures. Visual acceptability and perceptibility values of color differences are reviewed and new whiteness indexes to describe whiteness in dentistry are presented.

Results: In the last decade, the CIELAB 50:50% perceptibility and acceptability thresholds were set to 1.2 and 2.7, respectively, and the CIEDE2000 50:50% perceptibility and acceptability thresholds were set to 0.8 and 1.8. The CIEDE2000 color-difference formula became increasingly popular in dentistry. Developments in color science have led to the description of tooth whiteness and changes in tooth whiteness based on whiteness indexes, with the most relevant being the WID whiteness index, which is a customized index based in CIELAB color space.

Conclusion: The application of color science in dentistry has allowed the precise description of tooth color and whiteness. The revised and new CIEDE2000 color-difference formula is expected to fully replace the outdated CIELAB formula in almost all dental applications. Recent psychophysical studies have reported values of visual thresholds and new whiteness indexes, which can serve as quality control tools to guide the selection of esthetic dental materials, evaluate clinical performance, and interpret visual and instrumental findings in clinical dentistry, dental research, and subsequent standardization. To read out more, please visit: http://www.eurekaselect.com/163911/article

Open Access Articles | Platelet Concentrates in Oral Surgery: Indications and Limits. A Literature Review

Journal Name: Current Dentistry

Author(s): Gaetano Marenzi*, Med Erda Qorri, Pasquale Sammartino, Filomena Rusciano, Roberta Gasparro

 

 

Background: Platelet concentrates (PC) are blood-derived products for local application able to stimulate regeneration in soft and hard tissues, mimicking the physiological healing process. Their efficacy in oral surgical procedures is controversial and limited.

Objective: The study aims to critically analyze the available evidence for the effect of autogenous PC on wound healing of different oral surgical sites reported by more recent clinical studies.

Methods: Electronic and manual searches in three databases (Medline, Web of Science, Scopus) were performed to identify the clinical studies from January 2017 to December 2017 which reported the actual oral surgical indications and the benefit of local application of PC. All human studies evaluating PRP or PRF in a randomized controlled trial, case series, case report and systematic review were included. All animal, histologic and in vitro studies were excluded.

Results: Fifty-two studies were selected. The use of PRF was proposed in treating many oral surgical sites. Data availability with regard to the effect of PRF on new bone formation in GBR and horizontal/ vertical bone augmentation procedures varied from abundant to absent. Positive results concerning the effect of PRF on potential post-surgical complication (pain, swelling and trismus) were reported.

Conclusion: Few clinical indications could be determined: the literature on the topic was contradictory and the published data were difficult to interpret. Positive results were generally recorded for soft tissues and periodontal wound healing. No real benefit of PC application on bone regeneration was evidenced. To read out more, please visit: http://www.eurekaselect.com/163161/article

Open Access Articles | Improving Self-interacting Proteins Prediction Accuracy Using Protein Evolutionary Information and Weighed-Extreme Learning Machine

Journal Name: Current Bioinformatics

Author(s): Ji-Yong An*, Yong Zhou, Lei Zhang, Qiang Niu, Da-Fu Wang.

 

Background: Self Interacting Proteins (SIPs) play an essential role in various aspects of the structural and functional organization of the cell.

Objective: In the study, we presented a novelty sequence-based computational approach for predicting Self-interacting proteins using Weighed-Extreme Learning Machine (WELM) model combined with an Autocorrelation (AC) descriptor protein feature representation.

Method: The major advantage of the proposed method mainly lies in adopting an effective feature extraction method to represent candidate self-interacting proteins by using the evolutionary information embedded in PSI-BLAST-constructed Position Specific Scoring Matrix (PSSM); and then employing a reliable and effective WELM classifier to perform classify.

Result: In order to evaluate the performance, the proposed approach is applied to yeast and human SIP datasets. The experimental results show that our method obtained 93.43% and 98.15% prediction accuracies on yeast and human dataset, respectively. Extensive experiments are carried out to compare our approach with the SVM classifier and existing sequence-based method on yeast and human dataset. Experimental results show that the performance of our method is better than several other state-of-theart methods.

Conclusion: It is demonstrated that the proposed method is suitable for SIPs detection and can execute incredibly well for identifying Sips. In order to facilitate extensive studies for future proteomics research, we developed a freely available web server called WELM-AC-SIPs in Hypertext Preprocessor (PHP) for predicting SIPs. The web server including source code and the datasets are available at http://219.219.62.123:8888/WELMAC/. To read out more, please visit: http://www.eurekaselect.com/159690

Most Accessed Articles| Stroke Lesion Segmentation and Analysis using Entropy/Otsu’s Function – A Study with Social Group Optimization

Journal Name: Current Bioinformatics

Author(s): Suresh Chandra Satapathy*, Steven Lawrence Fernandes, Hong Lin.

 

 

Background: Stroke is one of the major causes for the momentary/permanent disability in the human community. Usually, stroke will originate in the brain section because of the neurological deficit and this kind of brain abnormality can be predicted by scrutinizing the periphery of brain region. Magnetic Resonance Image (MRI) is the extensively considered imaging procedure to record the interior sections of the brain to support visual inspection process.

Objective: In the proposed work, a semi-automated examination procedure is proposed to inspect the province and the severity of the stroke lesion using the MRI.

Method: Recently discovered heuristic approach called the Social Group Optimization (SGO) algorithm is considered to pre-process the test image based on a chosen image multi-thresholding procedure. Later, a chosen segmentation procedure is considered in the post-processing section to mine the stroke lesion from the pre-processed image.

Results: In this paper, the pre-processing work is executed with the well known thresholding approaches, such as Shannon’s entropy, Kapur’s entropy and Otsu’s function. Similarly, the postprocessing task is executed using most successful procedures, such as level set, active contour and watershed algorithm.

Conclusion: The proposed procedure is experimentally inspected using the benchmark brain stroke database known as Ischemic Stroke Lesion Segmentation (ISLES 2015) challenge database. The results of this experimental work authenticates that, Shannon’s approach along with the LS segmentation offers superior average values compared with the other approaches considered in this research work. To read out more, please visit: http://www.eurekaselect.com/168477