Genetic Variants Associated with the Risk of Stroke in Sickle Cell Anemia: Systematic Review and Meta-Analysis.

Sickle cell anemia (SCA) is the most common cause of stroke in children. As it is a rare disease, studies investigating the association with complications like stroke in SCD have small sample sizes. Here, we performed a systematic review and meta-analysis of the studies exploring an association of genetic variants with stroke to get a better indication of their association with stroke. PubMed and Google Scholar were searched to identify studies that had performed an association analysis of genetic variants for the risk of stroke in SCA patients. After screening of eligible studies, summary statistics of association analysis with stroke and other general information were extracted. Meta-analysis was performed using the fixed effect method on the tool METAL and forest plots were plotted using the R program. The random effect model was performed as a sensitivity analysis for loci where significant heterogeneity was observed. 407 studies were identified using the search term and after screening 37 studies that cumulatively analyzed 11,373 SCA patients were included. These 37 studies included a total of 2,222 SCA patients with stroke, predominantly included individuals of African ancestry (N = 16). Three of these studies performed whole exome sequencing while 35 performed single nucleotide-based genotyping. Though the studies reported association with 132 loci, meta-analyses could be performed only for 12 loci that had data from two or more studies. After meta-analysis we observed that four loci were significantly associated with risk for stroke: -α3.7 kb Alpha-thalassemia deletion (P = 0.00000027), rs489347-TEK (P = 0.00081), rs2238432-ADCY9 (P = 0.00085), rs11853426-ANXA2 (P = 0.0034), and rs1800629-TNF (P = 0.0003396). Ethnic representation of regions with a high prevalence of SCD like the Mediterranean basin and India needs to be improved for genetic studies on associated complications like stroke. Larger genome-wide collaborative studies on SCD and associated complications including stroke need to be performed.

Visible light-based 3D bioprinted composite scaffolds of κ-carrageenan for bone tissue engineering applications.

Three-dimensional (3D) printing of bone scaffolds using digital light processing (DLP) bioprinting technology empowers the treatment of patients suffering from bone disorders and defects through the fabrication of cell-laden patient-specific scaffolds. Here, we demonstrate the visible-light-induced photo-crosslinking of methacrylate-κ-carrageenan (MA-κ-CA) mixed with bioactive silica nanoparticles (BSNPs) to fabricate 3D composite hydrogels using digital light processing (DLP) printing. The 3D printing of complex bone structures, such as the gyroid, was demonstrated with high precision and resolution. DLP-printed 3D composite hydrogels of MA-κ-CA-BSNP were prepared and systematically assessed for their macroporous structure, swelling, and degradation characteristics. The viscosity, rheological, and mechanical properties were also investigated for the influence of nanoparticle incorporation in the MA-κ-CA hydrogels. The in vitro study performed with MC3T3-E1 pre-osteoblast-laden scaffolds of MA-κ-CA-BSNP revealed high cell viability, no cytotoxicity, and proliferation over 21 days with markedly enhanced osteogenic differentiation compared to neat polymeric scaffolds. Furthermore, no inflammation was observed in the 21-day study involving the in vivo examination of DLP-printed 3D composite scaffolds in a Wistar rat model. Overall, the observed results for the DLP-printed 3D composite scaffolds of MA-κ-CA and BSNP demonstrate their biocompatibility and suitability for bone tissue engineering.

Impact of the COVID-19 Pandemic on Blood Donation Patterns: A Systematic Review and Meta-Analysis.

Blood centers, which are arguably the backbone of every hospital, depend on blood donors for a constant and regular supply of blood. Like many other fields, the COVID-19 pandemic severely affected blood donations. In this article, we aim to systematically search the studies done on blood donation during the COVID-19 pandemic period, analyze the pandemic's effect on blood donation, and examine the methodology used to overcome the problem. We performed a systematic review and meta-analysis to investigate the effect of the COVID-19 pandemic on blood donation. Two independent reviewers searched different databases, such as PubMed, ProQuest, Scopus, and Google Scholar. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the Joanna Briggs Institute critical appraisal checklist for overall study characteristics. We included a total of 15 studies. There was an overall decrease in blood donation of 25%, with some regions showing a decrease of as much as 71%. However, some regions were able to experience a 2-10% increase in blood donation after taking stringent and early measures to prevent such decreases. The COVID-19 pandemic and consequent lockdown greatly affected blood transfusion services, resulting in a progressive decline in blood donations that threatened the lives of many patients who were fully dependent on blood transfusion. However, by making appropriate and early decisions and taking action, policymakers and the rest of society can prevent such shortages, potentially saving millions of lives.

Immunological survey of COVID-19 among medicos of tribal preponderant state of India.

Background: Immunological Survey or serosurveys have yielded useful information regarding the spread of the COVID-19 pandemic in the general population, but the impact of the continuing pandemic on the medical students in India is yet to be fully recognised. In this study we assessed the students who had received at least two doses of the COVID-19 vaccine for their antibody response. Methodology: A Hospital based, age-stratified, cross-sectional Analytical study design was adopted for the survey, carried out in tribal state of India among medical students. Consecutive sampling method was used where serum samples were tested for antibodies against the SARS-CoV-2 nucleocapsid (N) protein. Result: The vaccinee group comprised of 187 students mostly aged between 18-23 years 68.4% were females, 56.6 % were vaccinated with covishield. The mean IgG (Immunoglobin G) titre was 7343.74 AU/Ml, less than 1000 AU/Ml was found in 8% of participants, while more than 8000 AU/Ml was found in 32.1%. Participants who got the covaxin vaccine had a higher median IgG titre (median 6491.8 AU/mL, interquartile range 8898 AU/mL).The antibody titre of male was 0.328 times lower than that of female. Conclusion: Despite the fact that covishield's mean antibody titre was higher, covaxin's protection lasted longer.

Bioinspired nanotopography on 3D printed tissue scaffold to impart mechanobactericidal and osteogenic activities.

The great demand for bone grafts has motivated the development of tissue scaffolds with osteogenic activity, whereas the risk of implant-associated infection, especially given the rise of antimicrobial resistance, has compelled the development of scaffolds with innovative antimicrobial strategies. Bioinspired mechanobactericidal nanostructures are highly appealing as an alternative to traditional chemical approaches. This study presents an innovative spin-coating setup for the generation of nanotopography on the surfaces of a three-dimensional (3D)-printed porous polylactide (PLA) scaffold based on the principle of polymer demixing. The nanostructured PLA surface exhibited excellent bactericidal activity by contact killing of P. aeruginosa (86.60 % dead cells in 24 h) and S. aureus (92.36 %). The nanoscale topography supported the attachment and proliferation of pre-osteoblasts and better supported osteogenic differentiation than the unmodified scaffold. These findings demonstrate a single-step spin coating to yield nanotopography on 3D-printed polymer scaffolds that concurrently impart mechanobactericidal and osteogenic activities. Taken together, this work has important implications for engineering the next-generation 3D printed bioactive tissue scaffolds.

Spatio-temporal analysis of air quality and its relationship with COVID-19 lockdown over Dublin.

Air pollution has become one of the biggest challenges for human and environmental health. Major pollutants such as Nitrogen Dioxide (NO 2 ), Sulphur Dioxide (SO 2 ), Ozone (O 3 ), Carbon Monoxide (CO), and Particulate matter (PM10 and PM2.5) are being ejected in a large quantity every day. Initially, authorities did not implement the strictest mitigation policies due to pressures of balancing the economic needs of people and public safety. Still, after realizing the effect of the COVID-19 pandemic, countries around the world imposed a complete lockdown to contain the outbreak, which had the unexpected benefit of causing a drastic improvement in air quality. The present study investigates the air pollution scenarios over the Dublin city through satellites (Sentinel-5P and Moderate Resolution Imaging Spectroradiometer) and ground-based observations. An average of 28% reduction in average NO 2 level and a 27.7% improvement in AQI (Air Quality Index) was experienced in 2020 compared to 2019 during the lockdown period (27 March-05 June). We found that PM10 and PM2.5 are the most dominating factor in the AQI over Dublin.

The changing contours of global value chains post-COVID: Evidence from the Commonwealth.

The COVID-19 pandemic emphasised the global value chains (GVCs) debate by focussing on whether gains from GVC participation outweigh firms associated risks of demand and supply shocks amid rising protectionism. This paper bridges the gap between the international trade and management literature by examining the impact of COVID-19 on Commonwealth countries, an area that has received scant attention in academic literature. Using the Eora database, we simulate scenarios to examine Commonwealth countries' participation in GVCs post-COVID. We draw on the transaction cost economics (TCE) theory to develop a framework that investigates whether growing protectionism, associated with reshoring, decoupling and nearshoring, could potentially affect the constellation and participation of Commonwealth countries in GVCs post-COVID. Results show that trade protectionism is likely to impact the supply chains and lead to GVC reconfiguration, which could offer opportunities for the Commonwealth countries and firms to potentially gain following the geographical redistribution of suppliers.

Digital light processing-based 3D bioprinting of κ-carrageenan hydrogels for engineering cell-loaded tissue scaffolds.

The demand to regenerate biological tissues and organs in patients as an alternative to transplants has motivated the tissue engineering field. Digital light processing (DLP)-based three-dimensional (3D) bioprinting technology enables the rapid fabrication of complex 3D cell-laden scaffolds for tissue engineering applications. Herein, we demonstrate the outstanding printability of photocurable methacrylate-κ-carrageenan (MA-κ-CA) using DLP 3D printing. 3D printed hydrogels with varying concentrations (1-5% w/v) of MA-κ-CA were thoroughly characterized for their swelling, degradation, mechanical, and rheological properties, and suitability for bioprinting with living cells. Viscosity and shear thinning behavior of MA-κ-CA faithfully recapitulate the biomechanical properties of soft human tissues. Encapsulated NIH-3T3 cells show high viability and good proliferation over several days. Furthermore, highly complex 3D hydrogel scaffolds of MA-κ-CA were printed to recapitulate the biological complexity of tissues and organs. This work presents a polysaccharide bioink for preparing tissue scaffolds by DLP 3D bioprinting.

Estimation of anti-SARS-CoV-2 IgG titre among blood donors in Ranchi.

Introduction: Coronavirus disease 2019 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as novel coronavirus (2019-nCoV). The disease presentation ranges from asymptomatic to severe acute respiratory failure requiring intensive care support. Anti-SARS-CoV-2 IgG antibodies are developed either by natural infection from SARS-CoV-2 or by vaccination against COVID-19. The persistence of IgG antibodies allows identification of the people who have been infected in the past, recovered from illness, and possibly become immune. 7 IgG detection and other serological assays will play an important role in research and surveillance. Aims and Objective: The objective of the study is to assess anti-SARS-CoV-2 IgG titre among blood donors and to assess the decreasing incidence of COVID-19 in the department of blood bank, Rajendra Institute of Medical Sciences, Ranchi, Jharkhand. Materials and Methods: An observational, cross-sectional study was conducted at the department of blood bank, Rajendra Institute of Medical Sciences, Ranchi, Jharkhand over a period of 2 months and 14 days from 06 February 2021 to 20 April 2021 who donated at least one unit of blood. Results: This study recorded a greater number of male donors with B+ blood group. The anti-SARS-CoV-2 titre were mostly young adults between 18 and 31 years of age. Conclusion: Seroprevalence was high in males having blood group B+ between 18 and 32 years of age.

The role of alliance management, big data analytics and information visibility on new-product development capability.

Many organizations are increasingly investing in building dynamic capabilities to gain competitive advantage. New products play an important role in gaining competitive advantage and can significantly boost organizational performance. Although new product development (NPD) is widely recognized as a potentially vital source of competitive advantage, organizations face challenges in terms of developing the right antecedents or capabilities to influence NPD performance. Our research suggests that organizations should invest in building alliance management capability (AMC), big data analytics capability (BDAC) and information visibility (IV) to achieve their desired NPD success. Informed by the dynamic capabilities view of the firm (DCV) we have stated seven research hypotheses. We further tested our hypotheses using 219 usable respondents gathered using a pre-tested instrument. The hypotheses were tested using variance based structural equation modelling (PLS-SEM). The results of our study paint an interesting picture. Our study makes some significant contribution to the DCV and offers some useful directions to practitioners engaged in NPD in the big data analytics era. We demonstrate that AMC and BDAC are lower-order dynamic capabilities and that AMC has a positive and significant influence on BDAC. In turn, AMC and BDAC influence NPD under the moderating influence of IV. Ours is one of the first studies to empirically establish an association among three distinct dynamic capabilities which are often considered in isolation: AMC, BDAC and NPD. Our findings support emergent views on dynamic capabilities and their classification into various orders. Lastly, we provide empirical evidence that information visibility acts as a contingent variable to both AMC and BDAC effects on NPD. We end our paper by outlining some limitations of our study and by offering useful future research directions.

Microwave synthesized strontium hexaferrite 2D sheets as versatile and efficient microwave catalysts for degradation of organic dyes and antibiotics.

Microwave catalysis is extremely lucrative due to prompt mineralization and superior efficiency. Ideal microwave catalysts should possess crystalline nature, large surface area, room temperature ferromagnetic, high dielectric properties apart from structural stability at elevated temperature. In the present article, the candidature of microwave synthesized strontium hexaferrite 2D sheets (2D SFO) has been explored as microwave catalysts for the degradation of a host of organic dyes and antibiotics. Malachite green (MG) and nile blue A (NB) in particular exhibited 99.8% and 97.6% degradation, respectively. Degradation reaction is established to follow pseudo-second-order kinetics. Total organic carbon (TOC) measurements hint at 52% and 60% mineralization for MG and NB, respectively. Liquid chromatography-mass spectroscopy (LCMS) measurements indicate the reaction pathways via intermediates and eventual mineralization to CO2 and H2O. Mott-Schottky measurements along with scavenger tests hint that both hydroxyl and superoxide radicals participate in the reaction. Having superior efficiency apart from the versatile nature of the 2D SFO microwave catalyst, the present research will guide to the emergence of microwave catalysis as a new technology.

Biomaterials-based formulations and surfaces to combat viral infectious diseases.

Rapidly growing viral infections are potent risks to public health worldwide. Accessible virus-specific antiviral vaccines and drugs are therapeutically inert to emerging viruses, such as Zika, Ebola, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therefore, discovering ways to prevent and control viral infections is among the foremost medical challenge of our time. Recently, innovative technologies are emerging that involve the development of new biomaterial-based formulations and surfaces endowed with broad-spectrum antiviral properties. Here, we review emerging biomaterials technologies for controlling viral infections. Relevant advances in biomaterials employed with nanotechnology to inactivate viruses or to inhibit virus replication and further their translation in safe and effective antiviral formulations in clinical trials are discussed. We have included antiviral approaches based on both organic and inorganic nanoparticles (NPs), which offer many advantages over molecular medicine. An insight into the development of immunomodulatory scaffolds in designing new platforms for personalized vaccines is also considered. Substantial research on natural products and herbal medicines and their potential in novel antiviral drugs are discussed. Furthermore, to control contagious viral infections, i.e., to reduce the viral load on surfaces, current strategies focusing on biomimetic anti-adhesive surfaces through nanostructured topography and hydrophobic surface modification techniques are introduced. Biomaterial surfaces functionalized with antimicrobial polymers and nanoparticles against viral infections are also discussed. We recognize the importance of research on antiviral biomaterials and present potential strategies for future directions in applying these biomaterial-based approaches to control viral infections and SARS-CoV-2.

Data for microbe resistant engineered recombinant spider silk protein based 2D and 3D materials.

Data presented in this article describe bacterial and fungal repellent properties of 2D-films and 3D-hydrogels made of different recombinantly produced spider silk proteins based on consensus sequences of Araneus diadematus dragline silk proteins (fibroin 3 and 4). Here, the attachment, growth, and microbial colonization of Streptococcus mutans (S. mutans) as well as Candida albicans (C. albicans) on plane and micro-patterned films were visualized by scanning electron microscopy (SEM). Also, microbial viability data are provided of Escherichia coli (E. coli) and Pichia pastoris (P. pastoris) on hydrogels made of eADF4(C16) and eADF4(C16)-RGD, quantified using the Alamar blue assay. Experimental results, design of a post-operative contamination model of microbes with mammalian cells, and methods in the data article refer to the research paper "Engineered spider silk-based 2D and 3D materials prevent microbial infestation" published recently [1].

Enhanced Antibacterial Activity of Se Nanoparticles Upon Coating with Recombinant Spider Silk Protein eADF4(κ16).

PURPOSE: Selenium nanoparticles (Se NPs) are promising antibacterial agents to tackle the growing problem of antimicrobial resistance. The aim of this study was to fabricate Se NPs with a net positive charge to enhance their antibacterial efficacy. METHODS: Se NPs were coated with a positively charged protein - recombinant spider silk protein eADF4(κ16) - to give them a net positive surface charge. Their cytotoxicity and antibacterial activity were investigated, with negatively charged polyvinyl alcohol coated Se NPs as a control. Besides, these eADF4(κ16)-coated Se NPs were immobilized on the spider silk films, and the antibacterial activity of these films was investigated. RESULTS: Compared to the negatively charged polyvinyl alcohol coated Se NPs, the positively charged eADF4(κ16)-coated Se NPs demonstrated a much higher bactericidal efficacy against the Gram-negative bacteria E. coli, with a minimum bactericidal concentration (MBC) approximately 50 times lower than that of negatively charged Se NPs. Cytotoxicity testing showed that the eADF4(κ16)-coated Se NPs are safe to both Balb/3T3 mouse embryo fibroblasts and HaCaT human skin keratinocytes up to 31 µg/mL, which is much higher than the MBC of these particles against E. coli (8 ± 1 µg/mL). In addition, antibacterial coatings were created by immobilising the eADF4(κ16)-coated Se NPs on positively charged spider silk films and these were shown to retain good bactericidal efficacy and overcome the issue of low particle stability in culture broth. It was found that these Se NPs needed to be released from the film surface in order to exert their antibacterial effects and this release can be regulated by the surface charge of the film, such as the change of the spider silk protein used. CONCLUSION: Overall, eADF4(κ16)-coated Se NPs are promising new antibacterial agents against life-threatening bacteria.

Recombinant Spider Silk-Silica Hybrid Scaffolds with Drug-Releasing Properties for Tissue Engineering Applications.

Fabricating biomaterials with antimicrobial activity to prevent the growth of detrimental microorganisms is of great scientific and practical interest. Here, composite materials comprising recombinant spider silk proteins and mesoporous silica nanoparticles (MSN) loaded with selected antibiotics and antimycotics are fabricated into films and hydrogels. The derived composite materials exhibit excellent antimicrobial properties with sustained release of antibiotics over the course of 15 days. Furthermore, antibiotics/antimycotics inclusion does not impair the cytocompatibility of the composite materials, all of which promote fibroblast cell adhesion and proliferation. Finally, processing of spider silk-MSN composite hydrogels using 3D printing is shown to enable the fabrication of patient-specific antimicrobial implants to prevent infection in the near future.

Recombinant Spider Silk Hydrogels for Sustained Release of Biologicals.

Therapeutic biologics (i.e., proteins) have been widely recognized for the treatment, prevention, and cure of a variety of human diseases and syndromes. However, design of novel protein-delivery systems to achieve a nontoxic, constant, and efficient delivery with minimal doses of therapeutic biologics is still challenging. Here, recombinant spider silk-based materials are employed as a delivery system for the administration of therapeutic biologicals. Hydrogels made of the recombinant spider silk protein eADF4(C16) were used to encapsulate the model biologicals BSA, HRP, and LYS by direct loading or through diffusion, and their release was studied. Release of model biologicals from eADF4(C16) hydrogels is in part dependent on the electrostatic interaction between the biological and the recombinant spider silk protein variant used. In addition, tailoring the pore sizes of eADF4(C16) hydrogels strongly influenced the release kinetics. In a second approach, a particles-in-hydrogel system was used, showing a prolonged release in comparison with that of plain hydrogels (from days to week). The particle-enforced spider silk hydrogels are injectable and can be 3D printed. These initial studies indicate the potential of recombinant spider silk proteins to design novel injectable hydrogels that are suitable for delivering therapeutic biologics.

Catalytic Macroporous Biohydrogels Made of Ferritin-Encapsulated Gold Nanoparticles.

Reported is a modular approach for the incorporation and stabilization of gold nanoparticles inside a three-dimensional macroporous hydrogel made of ferritin. The strategy, which involves the dynamic templating of surfactant H1 domains, demineralization, and remineralization helps to overcome aggregation and degradation issues usually associated with bare-metal-based nanocatalysts. The catalytic activity of the so-synthesized bionanocomposite hydrogel was demonstrated in both nitroaldol (Henry) and nitroreduction model reactions in aqueous solution at room temperature. An interesting synergistic effect between basic residues of the protein and the gold nanoparticles was found in the nitroaldol reaction when carried out in water in the presence of a phase-transfer catalyst. Furthermore, the reduction of 4-nitrophenol and 4-nitroaniline catalyzed by the nanocomposite scaffold in the presence of NaBH4 proceeded significantly faster than that using other known Au- and Ag-based catalysts under similar conditions.

Risk Assessment Tool for Pressure Ulcer Development in Indian Surgical Wards.

The aims of this paper were to compare the predictive validity of three pressure ulcer (PU) risk scales-the Norton scale, the Braden scale, and the Waterlow scale-and to choose the most appropriate calculator for predicting PU risk in surgical wards of India. This is an observational prospective cohort study in a tertiary educational hospital in New Delhi among 100 surgical ward patients from April to July 2011. The main outcomes measured included sensitivity, specificity, positive predictive value (PVP) and negative predictive value (PVN), and the area under the curve of the receiver operating characteristic (ROC) curve of the three PU risk assessment scales. Based on the cutoff points found most appropriate in this study, the sensitivity, specificity, PVP, and PVN were as follows: the Norton scale (cutoff, 16) had the values of 95.6, 93.5, 44.8, and 98.6, respectively; the Braden scale (cutoff, 17) had values of 100, 89.6, 42.5, and 100, respectively; and the Waterlow scale (cutoff, 11) had 91.3, 84.4, 38.8, and 97, respectively. According to the ROC curve, the Norton scale is the most appropriate tool. Factors such as physical condition, activity, mobility, body mass index (BMI), nutrition, friction, and shear are extremely significant in determining risk of PU development (p < 0.0001). The Norton scale is most effective in predicting PU risk in Indian surgical wards. BMI, mobility, activity, nutrition, friction, and shear are the most significant factors in Indian surgical ward settings with necessity for future comparison with established scales.

A molecular Fe-complex as a catalyst probe for in-gel visual detection of proteins via signal amplification.

We report the use of a molecular peroxidase mimic biuret-Fe-TAML for chemoselective labeling of proteins and the subsequent visual detection (<0.1 pmoles) of the conjugate in a polyacrylamide gel by catalytic signal amplification. Use of this probe in activity based protein profiling (ABPP) of serine proteases is also demonstrated.

Self-templated chemically stable hollow spherical covalent organic framework.

Covalent organic frameworks are a family of crystalline porous materials with promising applications. Although active research on the design and synthesis of covalent organic frameworks has been ongoing for almost a decade, the mechanisms of formation of covalent organic frameworks crystallites remain poorly understood. Here we report the synthesis of a hollow spherical covalent organic framework with mesoporous walls in a single-step template-free method. A detailed time-dependent study of hollow sphere formation reveals that an inside-out Ostwald ripening process is responsible for the hollow sphere formation. The synthesized covalent organic framework hollow spheres are highly porous (surface area ∼1,500 m(2 )g(-1)), crystalline and chemically stable, due to the presence of strong intramolecular hydrogen bonding. These mesoporous hollow sphere covalent organic frameworks are used for a trypsin immobilization study, which shows an uptake of 15.5 µmol g(-1) of trypsin.