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1.
Cureus ; 16(6): e61510, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38962593

ABSTRACT

Plateletpheresis has become a pivotal part of transfusion medicine. With the increasing demand for plateletpheresis, donor safety is an area of concern because plateletpheresis alters donor hematological parameters. For a better understanding of plateletpheresis, a systemic review is needed to study more evidence-based aspects of plateletpheresis. Electronic databases PubMed, Google Scholar, and Cochrane Library were used to find articles from January 1, 1980, to May 23, 2024. The random effect model was used to meta-analyze the effect of plateletpheresis on hematocrit, hemoglobin, and red blood cell (RBC) count. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed. A total of 24 studies were found; the effect of plateletpheresis on hemoglobin, hematocrit, and RBC count was studied in the following respective numbers of donors: 3,374, 3,374, and 690. A decrease of hemoglobin, hematocrit, and RBC count was observed after plateletpheresis having a weighted mean difference (WMD) of 0.50 (95%CI = -0.72 to -0.27), WMD of -1.36 (95%CI = -2.05 to -0.66), and WMD of -0.18 (95%CI = -0.23 to -0.12), respectively. Plateletpheresis shows a decrease in the value of hematological parameters such as hemoglobin, hematocrit, and erythrocyte count due to blood loss in the kits employed in the procedure; cell lysis was also seen because of exposure of erythrocytes to stress or change in osmotic pressure. Thus, strict criteria for donation must be developed for better safety of the donors. Improved automated cell separators for plateletpheresis should be made available in blood banks to ensure good quality hematologic products. Our findings suggest that the duration of the procedure should be decreased.

2.
Cureus ; 16(6): e62934, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39050285

ABSTRACT

INTRODUCTION: Hepatitis C is a global health burden with significant morbidity and mortality. It primarily affects the liver and causes acute hepatitis, chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Common modes of transmission of hepatitis C virus (HCV) infection are blood transfusion, needlestick injury, and mother-fetus transmission, among which transmission, blood transfusion is one of the most important causes. Blood transfusion is one of the pillars in the management of patients that saves lives and improves morbidity. Blood donation in India is done by voluntary and replacement blood donors of both sexes. The aim of this study is to determine the seroprevalence of HCV among blood donors in the Jharkhand state, a tribal-preponderant region of India, and to see the trend over the years. MATERIAL AND METHODS: This is a nine-year retrospective observational study from 2015 to 2023 that screened for anti-HCV antibodies (third-generation kit: Abbott Diagnostics) using the chemiluminescence technique. RESULTS: In this study, in total, 249,461 units of blood were collected, of which the majority of donations were by male and replacement donors (RDs) comprising 230,757 (92.50%) and 188,047 (75.38%), respectively. The mean number of blood donations by replacement and male donors (MDs) was more than for voluntary donors (VDs) and female donors (FDs) (20894.11 ± 3041.71 RDs vs. 6823.77 ± 2332.96 VDs, p < 0.0001 and 25639.66 ± 2810.08 MDs vs. 2078.22 ± 828.16 FD, p < 0.0001), respectively. The overall prevalence of HCV was 0.63%, and all seropositive donors were male. CONCLUSION: Replacement blood donation contributes to the major part of blood donation and is primarily done by males in this tribal population-dominant region of India. Seroprevalence of HCV is high in the population of this part of India, and there is a constant or slightly upward trend in hepatitis C infection among individuals.

3.
Cureus ; 16(5): e61154, 2024 May.
Article in English | MEDLINE | ID: mdl-38933647

ABSTRACT

Introduction Global health is still being impacted by the coronavirus disease 2019 (COVID-19) pandemic. Objectives We evaluated the antibody response in this study in individuals who received two doses of the COVID-19 vaccination, both with and without a history of SARS-CoV-2 infection. Methodology It was a hospital-based cross-sectional study conducted among healthcare personnel at a tertiary institution of a predominantly tribal state in India. Results A total of 187 medical students made up the vaccinee group; the majority (152; 81.3%) were between the ages of 18 and 23; 128 (68.4%) of the students were female; and 104 (55.6%) had received the Covishield (AstraZeneca plc, England, UK) vaccination. Of the subjects, 51 (27.3%) had a history of COVID-19 infection. For those who were infected, the antibody titer peaked after six months, whereas it took twice as long for those who were not. Up to a year later, the antibody titers for Covaxin (Bharat Biotech, Hyderabad, India) and Covishield remained equal; however, Covishield titers drastically decreased while Covaxin stayed constant when an infection history was present. Conclusion The study's findings show that immunization in individuals who have previously contracted COVID-19 induces a higher level of antibody response than immunization in individuals who have not previously contracted the virus.

4.
Hemoglobin ; 48(2): 101-112, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38637280

ABSTRACT

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.


Subject(s)
Anemia, Sickle Cell , Genetic Predisposition to Disease , Stroke , Anemia, Sickle Cell/genetics , Anemia, Sickle Cell/complications , Humans , Stroke/genetics , Stroke/epidemiology , Stroke/etiology , Genetic Variation , Polymorphism, Single Nucleotide , Risk Factors
5.
J Mater Chem B ; 12(7): 1926-1936, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38314524

ABSTRACT

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.


Subject(s)
Tissue Engineering , Tissue Scaffolds , Animals , Rats , Humans , Tissue Engineering/methods , Tissue Scaffolds/chemistry , Carrageenan/chemistry , Osteogenesis , Rats, Wistar , Hydrogels/chemistry , Light
6.
Cureus ; 15(8): e43384, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37700994

ABSTRACT

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.

7.
J Family Med Prim Care ; 12(8): 1669-1672, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37767453

ABSTRACT

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.

8.
Colloids Surf B Biointerfaces ; 228: 113401, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37315505

ABSTRACT

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.


Subject(s)
Anti-Infective Agents , Tissue Scaffolds , Tissue Scaffolds/chemistry , Osteogenesis , Staphylococcus aureus , Polyesters/pharmacology , Polyesters/chemistry , Polymers/chemistry , Anti-Infective Agents/pharmacology , Printing, Three-Dimensional , Tissue Engineering/methods
9.
Remote Sens Appl ; 28: 100835, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36196454

ABSTRACT

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.

10.
J Bus Res ; 153: 75-86, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35996441

ABSTRACT

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.

11.
Carbohydr Polym ; 290: 119508, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-35550782

ABSTRACT

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.


Subject(s)
Bioprinting , Animals , Bioprinting/methods , Carrageenan , Humans , Hydrogels , Methacrylates , Mice , Tissue Engineering/methods , Tissue Scaffolds
12.
J Family Med Prim Care ; 11(10): 6385-6389, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36618231

ABSTRACT

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.

13.
Ann Oper Res ; : 1-25, 2021 Nov 19.
Article in English | MEDLINE | ID: mdl-34815610

ABSTRACT

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.

14.
Sci Total Environ ; 790: 147853, 2021 Oct 10.
Article in English | MEDLINE | ID: mdl-34087737

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents , Microwaves , Catalysis , Coloring Agents , Strontium
15.
APL Bioeng ; 5(1): 011503, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33598595

ABSTRACT

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.

16.
Data Brief ; 32: 106305, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32995396

ABSTRACT

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].

17.
Int J Nanomedicine ; 15: 4275-4288, 2020.
Article in English | MEDLINE | ID: mdl-32606677

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents/pharmacology , Nanoparticles/chemistry , Recombinant Proteins/pharmacology , Selenium/pharmacology , Silk/pharmacology , 3T3 Cells , Animals , Cell Death/drug effects , Cell Survival/drug effects , Colony Count, Microbial , Escherichia coli/drug effects , Escherichia coli/growth & development , Fibroblasts/cytology , Fibroblasts/drug effects , Humans , Keratinocytes/cytology , Keratinocytes/drug effects , Mice , Mice, Inbred BALB C , Microbial Sensitivity Tests , Nanoparticles/ultrastructure , Particle Size
18.
Macromol Rapid Commun ; 41(1): e1900426, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31697434

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents/chemistry , Drug Carriers/chemistry , Silicon Dioxide/chemistry , Silk/chemistry , Animals , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Cell Adhesion/drug effects , Cell Line , Cell Proliferation/drug effects , Drug Liberation , Escherichia coli/drug effects , Fibroblasts/cytology , Fibroblasts/metabolism , Hydrogels/chemistry , Mice , Nanoparticles/chemistry , Printing, Three-Dimensional , Tissue Engineering
19.
ACS Biomater Sci Eng ; 4(5): 1750-1759, 2018 May 14.
Article in English | MEDLINE | ID: mdl-33445332

ABSTRACT

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.

20.
Chempluschem ; 82(2): 225-232, 2017 Feb.
Article in English | MEDLINE | ID: mdl-31961537

ABSTRACT

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.

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