Injectable hyaluronic acid based hydrogels for the repair of cartilage lesions

Hyaluronic acid (HA) is a natural polysaccharide which is found natively in cartilage tissue. HA hydrogels are formed by the modification of HA through its carboxyl and hydroxyl groups and subsequent crosslinking. For applications in cartilage repair, it has been found that HA hydrogels not only support and maintain chondrocyte viability and phenotype when cultured in vitro and in vivo, but also that HA hydrogel chemistry supports and promotes the chondrogenic differentiation of mesenchymal stem cells (MSCs). A promising, non-invasive method for the repair of cartilage lesions is based on the use of injectable hydrogels with desirable properties in combination with biomolecules and cells. Please click Additional Files below to see the full abstract

Estimation of Maximum Shear Capacity of RC Deep Beams Strengthened by NSM Steel Bars

يهدف هذا البحث الى تخمين تحمل القص الاقصى للعتبات الخرسانية المسلحة العميقة والمقواة  بتقنية التقوية قرب السطح باستخدام قضبان الحديد. من خلال اقتراح معادلة نصف وضعية بالاعتماد على نتائج مختبرية مع الاخذ بنظر الاعتبار مجموعة من المتغيرات المهمة و المؤثرة على سلوك هكذا عتبات مثل نسبة ذراع القص الى العمق الفعال (a/d ratio), مقاومة الانضغاط للخرسانة, زاوية ميل القضبان المطمورة, قطر تلك القضبان والمسافات بينها. لذا تم فحص ثلاثة عشر نموذج من الاعتاب الخرسانية المسلحة ذات نسب ذراع قص الى العمق الفعال مختلفة (a/d= 0.85, 1.136 and 1.42) . اذ تم تقسيم النماذج الى ثلاثة مجاميع اعتمادا على نسبة (a/d) وكل مجموعة تتكون من نموذج واحد غير مقوى كنموذج سيطرة واخرى مقواة بأساليب مختلفة من قضبان الحديد المطمورة قرب السطح. عند مقارنة النتائج المحسوبة والنتائج العملية وجد  ان هناك تطابق جيد بينهما وبمعامل تحديد عالي يساوي (95.4%), ولتأكيد جودة الصيغة المقترحة في تقدير قدرة القص فقد تم استخدامها لتقدير تلك القيمة لعينات موجودة في بعض البحوث السابقة. حيث تم الحصول على توافق جيد في تخمين تحمل القص مع القيم العملية في تلك البحوث  مع معامل تغاير (COV) منخفض.This work aims to estimate the maximum shear capacity of deep beams RC members strengthened by Near-Surface Mounted (NSM) steel bars.  This is done by using an assumed semi-empirical formula that depends on experimental tests. This formula will cover many principal parameters such as shear span to effective depth ratios (a/d), orientation angle of NSM steel bars, concrete compressive strength (f′c), bar’s diameter and their spacing. So, thirteen reinforced concrete deep beams with different (a/d) ratios equals (0.85, 1.136 and 1.42) were tested. These beams are categorized into three groups depending on (a/d) ratio, which contained one unstrengthen beam as a control specimen and others strengthened beams by different schemes of NSM steel bars. A comparison between the calculated and experimental values shows good agreement with high coefficient of determination (R2=95.4%). The proposed formula is also used to estimate shear capacity of some specimens that found in some previous literatures to confirm the validity of the formula in estimating shear capacity of different cases. Good agreement with low (COV) of the predicted shear capacity with the experimental values that found in literatures was obtained

Qualitative and quantitative phenolic compounds analysis of dicranopteris linearis different fractional polarities leaves extract

Dicranopteris linearis occupies in an open ground that contains poor soils and often colonizing disturbed space that partly shaded area. It has been known for various traditional values including medicinal, edible food, soil erosion protection, pen and furniture. Even though the plants possess both economic and medicinal value, they still form the neglected group of a plant. The present study was carried out to characterize the phenolic compounds in D. linearis leaves extract in different fractional polarities qualitative and quantitatively. Dried leaves of D. linearis were successfully extracted by using water extraction before separated by petroleum ether, ethyl acetate and butanol fractions. All the fractional extracts have been analysed by using GCTOF-MS and HPLC. The result from GCTOF-MS analysis of fractional extracts showed 38 compounds found in petroleum ether, ethyl acetate and butanol extracts. However, only four phenolic compounds were identified through HPLC analysis in ethyl acetate and butanol extracts which were 2-Methoxy-4-vinylphenol, Vanillin, 4-Hydroxybenzaldehyde and 4-Hydroxybenzohydrazide. The results revealed that D. linearis contained 699.83 ± 6.26 μg GAE /g DW of total phenolic acid whereas individual phenolic acids were predominantly caffeic acid (0.44 ± 0.01 μg/g DW) and ferulic acid (0.22 ± 0.00 μg/g DW) in ethyl acetate and caffeic acid (0.10 ± 0.00 μg/g DW) and 2-Coumaric acid (0.44 ± 0.00 μg/g DW) in butanol extracts. In the present study, the plant extracts demonstrated the highest phenolic compound detected in ethyl acetate and butanol compared to petroleum ether extract

Shaping of molecular weight distribution by iterative learning probability density function control strategies

A mathematical model is developed for the molecular weight distribution (MWD) of free-radical styrene polymerization in a simulated semi-batch reactor system. The generation function technique and moment method are employed to establish the MWD model in the form of Schultz-Zimmdistribution. Both static and dynamic models are described in detail. In order to achieve the closed-loop MWD shaping by output probability density function (PDF) control, the dynamic MWD model is further developed by a linear B-spline approximation. Based on the general form of the B-spline MWD model, iterative learning PDF control strategies have been investigated in order to improve the MWD control performance. Discussions on the simulation studies show the advantages and limitations of the methodology

Influence of growing location, harvesting season and post-harvest storage time on carotenoid biosynthesis in orange sweet potato (Ipomoea batatas) tuber flesh

Carotenoid content in plants differs due to several factors such as cultivar, maturity, climate, locality and storage. Improving the nutritional values of sweet potato is an important breeding goal and understanding the regulation, genetics and inheritance of carotenoid biosynthesis are vital to achieve this. Environmental conditions can have a marked influence on the accumulation of carotenoids in sweet potato tubers. Little is known about the effects of location, post-harvest storage time and harvesting season particularly on carotenoid biosynthesis. Therefore, this study aimed to investigate the effects of growing location, harvesting season and storage time on carotenoid biosynthesis in orange sweet potato tuber flesh. The results showed that orange sweet potato tubers contained α-carotene and β-carotene in the first and second harvesting season (year 2011 and 2012), whereas lutein and zeaxanthin were detected only in the third harvesting season (year 2013). Analysis of carotenoid profiles of the orange sweet potato tubers grown in three different locations confirmed that the harvesting season had a major effect on the total carotenoid content and the individual carotenoid compounds. The post-harvest storage time of sweet potato tubers also appears to have distinct effects on carotenoid biosynthesis, the magnitude of the effects being dependent on the storage time, harvesting season and location. The results of this study will help to understand the effects of location, year of harvesting season and storage time on carotenoid accumulation in orange sweet potato tubers

Characterization of carotenoids content and composition of saffron from different localities

The most essential carotenoids for humans are found in plants that are normally yellow, orange, and red coloured pigments. They are typically and mostly lipophilic in nature, but some unique plant species may yield watersoluble carotenoids. Saffron or Crocus sativus contains hydrophilic carotenoids named crocin. Thus, this paper will describe the extraction and characterization of hydrophilic and lipophilic carotenoids (colour properties) obtained from saffrons of different geographical origins. They are specifically the Iranian, Turkish, and Kashmiri saffron respectively. Maceration techniques have been employed to extract the targeted compounds, whereas the characterization of the compounds has been analysed using HPLC. The extraction and characterization of carotenoids in saffron from different geographical origins found that the amount of crocin content was substantially higher in Iranian saffron, which was 11414.67 ± 516.34 μg/g DW followed by Turkish and Kashmiri saffron. Lipohilic carotenoids (i.e. crocetin, β-carotene, and zeaxanthin) were detectable in Iranian and Turkish saffron but absent in Kashmiri saffron. Similarly, the highest amount of crocetin content was found in Iranian saffron at 1054.73 ± 50.31 μg/g DW, while the highest amount of β-carotene and zeaxanthin was found in Turkish saffron at 512.92 ± 79.98 μg/g DW and 252.04 ± 60.34 μg/g DW, respectively. There was a marked difference in carotenoid composition sourced from different localities. Various environmental factors like climatic conditions, agricultural practices, stigma separation, and storing and drying processes may play an important role to explain such differenc

Accuracy of ultrasound versus computed tomography in diagnosis of maxillary sinusitis

Background: ultrasound offers non-invasive, rapid and simple method for confirming the clinical diagnosis of maxillary sinus pathologies. Objective: to evaluate the accuracy of real time ultrasound compared with the computed tomography in evaluation of maxillary sinusitis. Patients and materials: This comparative cross-sectional study was done on 42 patients referred for computed tomography examination of paranasal sinuses in Al-Yarmook Teaching Hospital-Baghdad, from October 2012 to February 2013 with patients clinically suggesting an underlying maxillary sinusitis. Ultrasound and computed tomography examinations were carried out on the same day, the ultrasound being the first investigation. The sample of this study consisted of 26 men and 16 women. The age of patients ranged between 20-60 years, mean age equal to 38 years. Our patients were randomly selected. Results: The results are based on the data analysis of total forty two [84 sinuses] patients with symptoms and/or signs of maxillary sinus diseases. In this study, real time B-mode ultrasonography of maxillary compared with computed tomography had a 81.8% sensitivity, 100 % specificity and 90.4% accuracy. The present study showed that total opacity of the maxillary sinus on computed tomography frequently gave a positive full sinus scan [77.7%] while the rest shows partial sinus scan [22.3%]. All patients with positive full sinus scan on ultrasound of maxillary sinuses have total opacity on computed tomography. Conclusion: Ultrasound can help as one of primary investigations of maxillary sinusitis. A positive full sinus scan appeared specific for total opacity of the maxillary sinus on computed tomography. A postural adjustment of the patient slightly bent foreword reduces the false negative results

Mucus-Penetrating Nanosuspensions for Enhanced Delivery of Poorly Soluble Drugs to Mucosal Surfaces

Mucus-penetrating Nanosuspensions, consisting of pure hydrophobic therapeutics with dense muco-inert coatings that enable particles to effectively bypass the mucus barrier, demonstrate superior drug distribution and absorption at mucosal surfaces. With significantly increased drug load compared to polymeric systems and established clinical translation of nanosuspensions-based products, mucus-penetrating nanosuspensions are a promising vehicle for improving mucosal delivery of poorly soluble drugs