Fibrin and poly(lactic-co-glycolic acid) hybrid scaffold promotes early chondrogenesis of articular chondrocytes: an <Emphasis Type="Italic">in vitro</Emphasis> study

Background  

Synthetic- and naturally derived- biodegradable polymers have been widely used to construct scaffolds for cartilage tissue engineering. Poly(lactic-co-glycolic acid) (PLGA) are bioresorbable and biocompatible, rendering them as a promising tool for clinical application. To minimize cells lost during the seeding procedure, we used the natural polymer fibrin to immobilize cells and to provide homogenous cells distribution in PLGA scaffolds. We evaluated in vitro chondrogenesis of rabbit articular chondrocytes in PLGA scaffolds using fibrin as cell transplantation matrix.     

Statistical Optimization for Acid Hydrolysis of Microcrystalline Cellulose and Its Physiochemical Characterization by Using Metal Ion Catalyst

Hydrolyzing the amorphous region while keeping the crystalline region unaltered is the key technology for producing nanocellulose. This study investigated if the dissolution properties of the amorphous region of microcrystalline cellulose can be enhanced in the presence of Fe³⁺ salt in acidic medium. The process parameters, including temperature, time and the concentration of metal chloride catalyst (FeCl₃), were optimized by using the response surface methodology (RSM). The experimental observation demonstrated that temperature and time play vital roles in hydrolyzing the amorphous sections of cellulose. This would yield hydrocellulose with higher crystallinity. The factors that were varied for the production of hydrocellulose were the temperature (x₁), time (x₂) and FeCl₃ catalyst concentration (x₃). Responses were measured in terms of percentage of crystallinity (y₁) and the yield (y₂) of the prepared hydrocellulose. Relevant mathematical models were developed. Analysis of variance (ANOVA) was carried out to obtain the most significant factors influencing the responses of the percentage of crystallinity and yield. Under optimum conditions, the percentage of crystallinity and yield were 83.46% and 86.98% respectively, at 90.95 °C, 6 h, with a catalyst concentration of 1 M. The physiochemical characteristics of the prepared hydrocellulose were determined in terms of XRD, SEM, TGA and FTIR analyses. The addition of FeCl₃ salt in acid hydrolyzing medium is a novel technique for substantially increasing crystallinity with a significant morphological change.     

Simple Response Surface Methodology: Investigation on Advance Photocatalytic Oxidation of 4-Chlorophenoxyacetic Acid Using UV-Active ZnO Photocatalyst

The performance of advance photocatalytic degradation of 4-chlorophenoxyacetic acid (4-CPA) strongly depends on photocatalyst dosage, initial concentration and initial pH. In the present study, a simple response surface methodology (RSM) was applied to investigate the interaction between these three independent factors. Thus, the photocatalytic degradation of 4-CPA in aqueous medium assisted by ultraviolet-active ZnO photocatalyst was systematically investigated. This study aims to determine the optimum processing parameters to maximize 4-CPA degradation. Based on the results obtained, it was found that a maximum of 91% of 4-CPA was successfully degraded under optimal conditions (0.02 g ZnO dosage, 20.00 mg/L of 4-CPA and pH 7.71). All the experimental data showed good agreement with the predicted results obtained from statistical analysis.     

Should COVID-19 Vaccines Authorized for Emergency Use Be Considered “Essential” Medicines?

A critical debate in the race to develop, market, and distribute COVID-19 vaccines could define the future of this pandemic: How much evidence demonstrating a vaccine’s safety and efficacy should be required before it is considered “essential”? If a COVID-19 vaccine were to be designated an essential medicine by the World Health Organization, this would invoke special “core” human rights duties for governments to provide the vaccine as a matter of priority irrespective of resource constraints. States would also have duties to make the vaccine available in adequate amounts, in the appropriate dosage forms, with assured quality and adequate information, and at an affordable price. This question is especially critical and unique given that COVID-19 vaccines have in many cases been authorized for use via national emergency use authorization processes—mechanisms that enable the public to gain access to promising medical products before they have received full regulatory approval and licensure. In this paper, we examine whether unlicensed COVID-19 vaccines authorized for emergency use should ever be considered essential medicines, thereby placing prioritized obligations on countries regarding their accessibility and affordability.     

Curcumin's Effect on Inflammatory Response following Percutaneous Coronary Intervention in Adult Patients with Stable Coronary Heart Disease

Cardiovascular diseases play major roles in the health problems worldwide especially in Indonesia. Percutaneous coronary intervention (PCI) is a minimally invasive procedure with relatively low complications. However, high inflammatory response post-PCI has showed adverse events even after administration of standard medication. Previous studies showed that curcumin was able to reduce inflammatory response in adult patients with stable coronary heart disease (CHD). This article determines the efficacy of oral administration of curcumin in reducing inflammatory response post-PCI with stable CHD. A double-blind randomized controlled trial on 50 adult patients comparing curcumin and placebo was performed in Cipto Mangunkusumo General Hospital and Jakarta Heart Center within April and June 2015. Either curcumin (45 mg/day) or placebo was given 7 days prior to PCI until 2 days after PCI. Inflammatory markers (high-sensitivity C-reactive protein [hsCRP] and soluble CD40 ligand [sCD40L]) were measured in three phases (7 days prior PCI, 24 hours post-PCI, and 48 hours post-PCI). There were no significant differences in the reduction of hsCRP and sCD40L between curcumin and placebo groups in three phases of measurement. Curcumin significantly reduce the serum hsCRP ( p  = 0.006) and sCD40L ( p  = 0.002) 7 days before PCI to 48 hours post-PCI. The decrement of hsCRP (−14.2% vs. –7.4%) and sCD40L (−24.3% vs. –13.2%) from 24 to 48 hours post-PCI was higher in the curcumin group than placebo group. The administration of curcumin 45 mg dose daily for 7 days prior PCI until 48 hours post-PCI is useful in reducing inflammatory response post-PCI with stable CHD.     

The Putative Roles and Functions of Indel,Repetition and Duplication Events in Alphavirus Non-Structural Protein 3 Hypervariable Domain (nsP3 HVD) in Evolution,Viability and Re-Emergence

Alphavirus non-structural proteins 1–4 (nsP1, nsP2, nsP3, and nsP4) are known to be crucial for alphavirus RNA replication and translation. To date, nsP3 has been demonstrated to mediate many virus–host protein–protein interactions in several fundamental alphavirus mechanisms, particularly during the early stages of replication. However, the molecular pathways and proteins networks underlying these mechanisms remain poorly described. This is due to the low genetic sequence homology of the nsP3 protein among the alphavirus species, especially at its 3′ C-terminal domain, the hypervariable domain (HVD). Moreover, the nsP3 HVD is almost or completely intrinsically disordered and has a poor ability to form secondary structures. Evolution in the nsP3 HVD region allows the alphavirus to adapt to vertebrate and insect hosts. This review focuses on the putative roles and functions of indel, repetition, and duplication events that have occurred in the alphavirus nsP3 HVD, including characterization of the differences and their implications for specificity in the context of virus–host interactions in fundamental alphavirus mechanisms, which have thus directly facilitated the evolution, adaptation, viability, and re-emergence of these viruses.     

Understanding effects of precursor solution aging in triple cation lead perovskite

The solution process is the most widely used method to prepare perovskite absorbers for high performance solar cells due to its ease for fabrication and low capital cost. However, an insufficient level of reproducibility of the solution process is often a concern. Complex precursor solution chemistry is likely one of the main reasons for the reproducibility issue. Here we report the effects of triple cation lead mixed-halide perovskite precursor solution aging on the quality of the resulting films and the device performance. Our study revealed that precursor solution aging has a great influence on the colloidal size distribution of the solution, which then affects the phase purity of the films and device performance. We determined the optimum aging hours that led to the best device efficiency along with the highest reproducibility. Dynamic light scattering revealed the formation of micron-sized colloidal intermediates in the solution when aged longer than the optimum hours and further analysis along with X-ray diffraction measurements suggested there were two chemical origins of the large aggregates, FA-based and Cs-based complexes.

The solution process is the most widely used method to prepare perovskite absorbers for high performance solar cells due to its ease for fabrication and low capital cost.     

Anticancer,antiplatelet, gastroprotective and hepatoprotective effects of camel urine: A scoping review

Camel urine has traditionally been used to treat multiple human diseases and possesses the most beneficial effects amongst the urine of other animals. However, scientific review evaluating the anticancer, antiplatelet, gastroprotective and hepatoprotective effects of camel urine is still scarce. Thus, this scoping review aimed to provide scientific evidence on the therapeutic potentials of camel urine. Three databases were searched to identify relevant articles (Web of Science, PubMed and Scopus) up to September 2020. Original articles published in English that investigated the effects of camel urine in various diseases were included. The literature search identified six potential articles that met all the inclusion criteria. Three articles showed that camel urine possesses cytotoxic activities against different types of cancer cells. Two studies revealed camel urine’s protective effects against liver toxicity and gastric ulcers, whilst another study showed the role of camel urine as an antiplatelet agent. All studies demonstrated significant positive effects with different effective dosages. Thus, camel urine shows promising therapeutic potential in treating human diseases, especially cancer. However, the standardised dosage and potential side effects should be determined before camel urine could be offered as an alternative treatment.