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Polyetheretherketone (PEEK)/polyetherimide (PEI) blends (50/50, v/v) keeping the crystal phase of PEEK have been manufactured by alternate PEEK/PEI layer stacking. This strategy avoided the complete miscibility of both polymers, keeping layers of PEEK and PEI unmixed along the sample thickness, as well as promoting the formation of a smooth interfacial layer where PEEK and PEI were mixed. The properties of this interface after processing at molten state and different times was studied by DSC, DMA, and X-Ray synchrotron. These techniques allowed monitoring the evolution of glass transition, where isolated Tg's for both pristine polymers were observed even after long processing time. PEEK crystallinity slightly decreased during manufacturing, whereas PEEK crystal parameters did not vary. These observations show that, although the interface-the zone where both polymers are mixed-grew, layers with pristine polymers remained even after prolonged processing time. The preservation of the PEEK crystallinity was also observed in the mechanical properties of the multilayer PEEK/PEI films, which were compared with pristine PEEK and PEI films. Multilayer samples processed for shorter times rendered higher young modulus, tensile strength, and strain at break.Background Alternative tobacco product (ATP) use has bee linked to critical illness, however, few studies have examined the use of these substances in critically ill populations. We sought to examine ATP use within critically ill patients and to define barriers in accurately assessing use within this population. Methods We prospectively studied 533 consecutive patients from the Early Assessment of Renal and Lung Injury study, enrolled between 2013 and 2016 at a tertiary referral center and a safety-net hospital. ATP use information (electronic cigarettes, cigars, pipes, hookahs/waterpipes, and snus/chewing tobacco) was obtained from the patient or surrogate using a detailed survey. Reasons for non-completion of the survey were recorded, and differences between survey responders vs. non-responders, self- vs. surrogate responders, and ATP users vs. non-users were explored. Results Overall, 80% (n = 425) of subjects (56% male) completed a tobacco product use survey. Of these, 12.2% (n = 52) reported current ATP use, while 5.6% reported using multiple ATP products. When restricted to subjects who were self-responders, 17% reported ATP use, while 10% reported current cigarette smoking alone. The mean age of ATP users was 57 ± 17 years. Those who did not complete a survey were sicker and more likely to have died during admission. Subjects who completed the survey as self-responders reported higher levels of ATP use than ones with surrogate responders (p less then 0.0001). Conclusion ATP use is common among critically ill patients despite them being generally older than traditional users. Survey self-responders were more likely than surrogate responders to report use. These findings highlight the importance of improving our current methods of surveillance of ATP use in older adults in the outpatient setting.In this work, we characterise the performance of a Sharp optical aerosol sensor model GP2Y1010AU0F. The sensor was exposed to different environments to a clean room, to a controlled atmosphere with known aerosol size distribution and to the ambient atmosphere on a busy city street. During the exposure, the output waveforms of the sensor pulses were digitised, saved and a following offline analysis enabled us to study the behaviour of the sensor pulse-by-pulse. A linear response of the sensor on number concentration of the monosized dispersed PSL particles was shown together with an almost linear dependence on particle diameters in the 0.4 to 4 micrometer range. The gathered data about the sensor were used to predict its response to an ambient atmosphere, which was observed simultaneously with a calibrated optical particle counter.Bracon brevicornis is an ectoparasitoid of a wide range of larval-stage Lepidopterans, including several pests of important crops, such as the corn borer, Ostrinia nubilalis. It is also one of the earliest documented cases of complementary sex determination in Hymenoptera. Here, we present the linked-read-based genome of B. brevicornis, complete with an ab initio-derived annotation and protein comparisons with fellow braconids, Fopius arisanus and Diachasma alloeum. We demonstrate the potential of linked-read assemblies in exploring regions of heterozygosity and search for structural and homology-derived evidence of the complementary sex determiner gene (csd).
Healthcare systems worldwide adapt to patients' needs and expectations, following social evolutions. Pharmaceutical practice has shifted towards activities such as therapeutic education. Such new missions require to prioritize human and social sciences, which now play a predominant role in training.
This work consists of assessing the contribution of human and social sciences to the field of pharmacy, with a twofold focus on practice and training.
A literature review was carried out according to the PRISMA guidelines focusing on the last 10 years. Selected full texts were read and analyzed to elicit the contribution of human and social sciences to pharmacy.
Overall 36 articles were included. Three specific topics were identified during an inductive process of full text analysis public health policy, patient care, and interprofessional collaboration.
Although human and social sciences are essential to the evolution of the pharmacist profession, their impact on health care costs remains difficult to evaluate. Moreover, teaching human and social sciences can prove difficult to standardize. Such approaches must be supported and organized by governments and universities with a view of upscaling practices.
Although human and social sciences are essential to the evolution of the pharmacist profession, their impact on health care costs remains difficult to evaluate. Moreover, teaching human and social sciences can prove difficult to standardize. Such approaches must be supported and organized by governments and universities with a view of upscaling practices.Drought is a major constraint in drylands for crop production. Plant associated microbes can help plants in acquisition of soil nutrients to enhance productivity in stressful conditions. The current study was designed to illuminate the effectiveness of desert rhizobacterial strains on growth and net-return of chickpeas grown in pots by using sandy loam soil of Thal Pakistan desert. A total of 125 rhizobacterial strains were isolated, out of which 72 strains were inoculated with chickpeas in the growth chamber for 75 days to screen most efficient isolates. Amongst all, six bacterial strains (two rhizobia and four plant growth promoting rhizobacterial strains) significantly enhanced nodulation and shoot-root length as compared to other treatments. These promising strains were morphologically and biochemically characterized and identified through 16sRNA sequencing. Then, eight consortia of the identified isolates were formulated to evaluate the growth and development of chickpea at three moisture levels (55%, 75% and 95% of field capacity) in a glass house experiment. The trend for best performing consortia in terms of growth and development of chickpea remained T2 at moisture level 1 > T7 at moisture level 2 > T4 at moisture level 3. The present study indicates the vital role of co-inoculated bacterial strains in growth enhancement of chickpea under low moisture availability. It is concluded from the results that the consortium T2 (Mesorhizobium ciceri RZ-11 + Bacillus subtilis RP-01 + Bacillus mojavensis RS-14) can perform best in drought conditions (55% field capacity) and T4 (Mesorhizobium ciceri RZ-11 + Enterobacter Cloacae RP-08 + Providencia vermicola RS-15) can be adopted in irrigated areas (95% field capacity) for maximum productivity of chickpea.China is one of the largest producers of pigs and pork in the world. However, large-scale studies on pig-associated Staphylococcus aureus in relation to healthy pigs, diseased pigs and environment are scarce. The objective of the present study was to characterize and compare S. aureus isolates from healthy pigs, diseased pigs and environment through antimicrobial susceptibility testing, multiple locus sequence typing, spa typing, and antimicrobial resistance gene screening. Results showed all isolates were susceptible to linezolid and vancomycin. However, 66.7% (104/156) isolates were multidrug-resistant by displaying resistance to three or more antibiotics and high rates of resistance to penicillin, tetracycline, clindamycin, and clarithromycin were observed. Of the 20 multilocus sequence types (STs) identified among the isolates, ST9, ST188, and ST7 were most commonly isolated from healthy pigs and environment, while ST1 was most commonly isolated from diseased pigs. In total, 17 spa types were represented among the isolates, while t4792 was most commonly isolated from diseased pigs and t899, t189 were most commonly isolated from healthy pigs and environment. In conclusion, the genotypic and epidemiology characteristics observed among the isolates suggest pigs and pork could be important players in S. aureus dissemination.Human cerebellar development occurs late in gestation and is hindered by preterm birth. The fetal development of Purkinje cells, the primary output cells of the cerebellar cortex, is crucial for the structure and function of the cerebellum. However, morphological and electrophysiological features in Purkinje cells at different gestational ages, and the effects of neonatal intensive care unit (NICU) experience on cerebellar development are unexplored. Utilizing the non-human primate baboon cerebellum, we investigated Purkinje cell development during the last trimester of pregnancy and the effect of NICU experience following premature birth on developmental features of Purkinje cells. Immunostaining and whole-cell patch clamp recordings of Purkinje cells in the baboon cerebellum at different gestational ages revealed that molecular layer width, driven by Purkinje dendrite extension, drastically increased and refinement of action potential waveform properties occurred throughout the last trimester of pregnancy. Preterm birth followed by NICU experience for 2 weeks impeded development of Purkinje cells, including action potential waveform properties, synaptic input, and dendrite extension compared with age-matched controls. In addition, these alterations impact Purkinje cell output, reducing the spontaneous firing frequency in deep cerebellar nucleus (DCN) neurons. Taken together, the primate cerebellum undergoes developmental refinements during late gestation, and NICU experience following extreme preterm birth influences morphological and physiological features in the cerebellum that can lead to functional deficits.The purpose of this study was to qualitatively explore the per- and poly-fluoroalkyl substances (PFAS) exposure experience and associated stressors, to inform public health efforts to support psychosocial health and resilience in affected communities. Semi-structured interviews (n = 9) were conducted from July-September 2019 with community members and state public health department representatives from areas with PFAS-contaminated drinking water. Thematic analysis was completed and themes were described and summarized. Reported stressors included health concerns and uncertainty, institutional delegitimization and associated distrust, and financial burdens. Interviewees provided several strategies to reduce stress and promote stress coping capacity and resilience, including showing empathy and validating the normalcy of experiencing stress; building trust through visible action and sustained community engagement; providing information and actionable guidance; discussing stress carefully; fostering stress coping capacity and resilience with opportunities to build social capital and restore agency; and building capacity among government agencies and health care providers to address psychosocial stress. While communities affected by PFAS contamination will face unavoidable stressors, positive interactions with government responders and health care providers may help reduce negative stress. More research on how best to integrate community psychosocial health and stress coping and resilience concepts into the public health response to environmental contamination could be helpful in addressing these stressors.The thalamus has been implicated in many cognitive processes, including long-term memory. More specifically, the anterior (AT) and mediodorsal (MD) thalamic nuclei have been associated with long-term memory. Despite extensive mapping of the anatomical connections between these nuclei and other brain regions, little is known regarding their functional connectivity during long-term memory. The current study sought to determine which brain regions are functionally connected to AT and MD during spatial long-term memory and whether sex differences exist in the patterns of connectivity. During encoding, abstract shapes were presented to the left and right of fixation. During retrieval, shapes were presented at fixation, and participants made an "old-left" or "old-right" judgment. Activations functionally connected to AT and MD existed in regions with known anatomical connections to each nucleus as well as in a broader network of long-term memory regions. Sex differences were identified in a subset of these regions. A targeted region-of-interest analysis identified anti-correlated activity between MD and the hippocampus that was specific to females, which is consistent with findings in rodents. The current results suggest that AT and MD play key roles during spatial long-term memory and suggest that these functions may be sex specific.Leptospermum petersonii (family Myrtaceae) is often cultivated for ornamental purposes but also serves as a rich source of bioactive essential oils. While several studies focused on the activities of the essential oils, this study analysed the potential of spent L. petersonii leaves as a natural food preservative.
We investigated the in vitro antioxidant and antimicrobial activities of crude
extracts against activities of the purified isolated flavonoid, 6-methyltectochrysin, which was characterized using spectroscopic methods. The antioxidant assays followed ORAC, FRAP and TEAC tests. The antimicrobial activities of the extract and purified flavonoid were analysed against six multi-drug resistant microbial strains in broth dilution assays.
The results revealed that both the crude extracts and isolated 6-methyltectochrysin exhibited positive radical ion scavenging antioxidant potential, however the crude extract was about 6-fold more potent antioxidant than the purified 6-methyltectochrysin. The crude extract also showed strong antimicrobial activities against
, and even more potent antimicrobial agent than the reference ampicillin antibiotic against
subsp.
A higher resistance was observed for the tested Gram-negative strains than for the Gram-positive ones. 6-methyltectochrysin was generally inactive in the antimicrobial assays.
The crude methanolic extract showed significant bioactivity which validates the medicinal relevance of the plant. The observed biological activities, especially against a notorious strain of
suggest that
could be a promising natural source of food preservatives.
The crude methanolic extract showed significant bioactivity which validates the medicinal relevance of the plant. The observed biological activities, especially against a notorious strain of B. cereus, suggest that L. petersonii could be a promising natural source of food preservatives.
Patients with hematological malignancies (HM), including multiple myeloma (MM), frequently suffer from immune deficiency-associated infectious complications because of both the disease and the treatment. Alarming results from China and the UK confirm the vulnerability of HM patients to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-driven coronavirus disease 2019 (COVID-19). Given that the immunoassay interference from the endogenous monoclonal immunoglobulin (M paraprotein) and treatment antibodies continually challenges the MM management, it is critical to evaluate the SARS-CoV-2 serology tests for suspected interference/cross-reactivity.
We compared the degree of interference in three SARS-CoV-2 serology assay platforms in HM patients with and without COVID-19 and on various therapeutic monoclonal antibody (t-mAb) treatments. Further, we confirmed the cross-reactivity in pooled samples from normal and COVID-19 + samples spiked with respective antibodies in vitro.
None of the 93 HM patient samples with or without t-MAbs showed cross-reactivity on any of the three serology platforms tested.
The tested three serologic assays for SARS-CoV-2 are specific and do not have cross-reactivity with M-components or t-MAbs indicating that they can be used safely in oncology practice and in research exploring the immunologic response to COVID-19 in patients with HM.
The tested three serologic assays for SARS-CoV-2 are specific and do not have cross-reactivity with M-components or t-MAbs indicating that they can be used safely in oncology practice and in research exploring the immunologic response to COVID-19 in patients with HM.The present study was carried out to determine some biochemical characteristics, in particular the total polyphenol content and the free radical scavenging activity, of the extracts recovered from bulbs and aerial parts (these last often considered as by-products) of two landraces of A. ampeloprasum var. holmense cultivated in Southern Italy. For the first time, the capacity of the extracts of these landraces to inhibit the formation of biofilm of different Gram-negative and Gram-positive bacteria and to affect the metabolism of the cells present within the bacterial biofilm was evaluated. All extracts exhibited an amount of total polyphenols not lower than 2.86 mg/g of dried product and revealed a noteworthy antioxidant activity, with EC50 values not exceeding 4.95 mg. In both cases, the aerial parts extracts were more effective than the bulb extracts, which also showed a minor amount of total polyphenols. The extracts inhibited mainly the adhesive capability of Pseudomonas aeruginosa and Staphylococcus aureus, by 95.78% and 85.01%, respectively. The extracts demonstrated to inhibit also the metabolism of the bacterial cells reaching levels up to 90%. Finally, as assessed by the assays performed on the 24-h preformed biofilms, all the extracts were also capable to cause a reduction in bacterial biomass and to affect their metabolism.Uncontrolled use of drugs both in humans and animals coupled with environmental contamination exacerbate the development and spread of antimicrobial resistance. This paper assessed the drivers of antimicrobial use and resistance in poultry and domestic pig farming and the environment. Questionnaires, in-depth interviews, and focus group discussions (FGDs) were used to collect information regarding demographic characteristics, knowledge, practices, attitudes, and perceptions of the drivers of antimicrobial use and resistance in animal farming and the environment. We found a higher proportion of usage of veterinary antimicrobials for prophylactic purposes (87.6%) in animal farming, than for therapeutic purposes (80.5%). The degree of farming experience was significantly (p less then 0.05) related to the knowledge on the source of antimicrobial use, methods used in disease diagnosis, access to veterinary services, stocking of antimicrobials at home, and presence of agriculture activities that involve the use of manure. Uncontrolled disposal of wastes from households, disposal of human and veterinary drugs, and weak implementation of the legal framework was identified as the major contributors to the environment. The high usage of veterinary antimicrobials and the environmental contamination identified requires multisectoral interventions, as well as a review of government strategies, policies, and regulations on antimicrobial use.In this work, a double-deck microfluidic chip was presented for digital PCR application. This chip consists of two reverse-placed micro-patterned polydimethylsiloxane (PDMS) layers between the top and bottom glass substrates. Each micropatterned PDMS layer contains more than 20,000 cylindrical micro-chambers to hold the partitioned droplets. The double-deck designs can double the number of chambers and reagent capacity without changing the planar area of the chip. In addition, carbon black was mixed into the pure PDMS gel to obstruct the passage of fluorescence from the positive chambers between the two layers of the chip. Thus, the fluorescence signal of micro-chambers in different layers of the chip after PCR can be collected without mutual interference. The quantitative capability of the proposed chip was evaluated by measuring a 10-fold serial dilution of the DNA template. A high accuracy of the absolute quantification for nucleic acid with a dynamic range of 105 was demonstrated by this chip in this work. Owing to its characteristics of small planar area, large capacity, and sensitivity, the double-deck microfluidic chip is expected to further promote the extensive applications of digital PCR.Despite worldwide efforts to understand the transmission dynamics of Zika virus (ZIKV), scanty evaluation has been made on the vector competence of Aedes aegypti fed directly on viremic human and non-human primates (NHPs). We blood-fed Ae. aegypti from two districts in Rio de Janeiro on six ZIKV infected pregnant rhesus macaques at several time points, half of which were treated with Sofosbuvir (SOF). Mosquitoes were analyzed for vector competence after 3, 7 and 14 days of incubation. Although viremia extended up to eight days post monkey inoculation, only mosquitoes fed on the day of the peak of viremia, recorded on day two, became infected. The influence of SOF treatment could not be assessed because the drug was administered just after mosquito feeding on day two. The global infection, dissemination and transmission rates were quite low (4.09%, 1.91% and 0.54%, respectively); no mosquito was infected when viremia was below 1.26 × 105 RNA copies/mL. In conclusion, Ae. aegypti vector competence for ZIKV from macaques is low, likely to be due to low viral load and the short duration of ZIKV viremia in primates suitable for infecting susceptible mosquitoes. If ZIKV infection in human and macaques behaves similarly, transmission of the Zika virus in nature is most strongly affected by vector density.Piscirickettsiasalmonis is an intracellular bacterial fish pathogen that causes piscirickettsiosis, a disease with numerous negative impacts in the Chilean salmon farming industry. Although transcriptomic studies of P. salmonis and its host have been performed, dual host-pathogen proteomic approaches during infection are still missing. Considering that gene expression does not always correspond with observed phenotype, and bacteriological culture studies inadequately reflect infection conditions, to improve the existing knowledge for the pathogenicity of P. salmonis, we present here a global proteomic profiling of Salmon salar macrophage-like cell cultures infected with P. salmonis LF-89. The proteomic analyses identified several P. salmonis proteins from two temporally different stages of macrophages infection, some of them related to key functions for bacterial survival in other intracellular pathogens. Metabolic differences were observed in early-stage infection bacteria, compared to late-stage infections.verall energy and ATP production alteration. Our global proteomic profiling and the current knowledge of the P. salmonis infection process allowed us to propose a model of the macrophage-P. salmonis interaction.The Transient Receptor Vanilloid 1 (TRPV1) or capsaicin receptor is a nonselective cation channel, which is abundantly expressed in nociceptors. This channel is an important transducer of several noxious stimuli, having a pivotal role in pain development. Several TRPV1 studies have focused on understanding its structure and function, as well as on the identification of compounds that regulate its activity. The intracellular roles of these channels have also been explored, highlighting TRPV1's actions in the homeostasis of Ca2+ in organelles such as the mitochondria. These studies have evidenced how the activation of TRPV1 affects mitochondrial functions and how this organelle can regulate TRPV1-mediated nociception. The close relationship between this channel and mitochondria has been determined in neuronal and non-neuronal cells, demonstrating that TRPV1 activation strongly impacts on cell physiology. This review focuses on describing experimental evidence showing that TRPV1 influences mitochondrial function.Flowering time is a critical stage for crop development as it regulates the ability of plants to adapt to an environment. To understand the genetic control of flowering time, a genome-wide association study (GWAS) was conducted to identify the genomic regions associated with the control of this trait in durum wheat (Triticum durum Desf.). A total of 96 landraces and 288 modern lines were evaluated for days to heading, growing degree days, and accumulated day length at flowering across 13 environments spread across Morocco, Lebanon, Mauritania, and Senegal. These environments were grouped into four pheno-environments based on temperature, day length, and other climatic variables. Genotyping with a 35K Axiom array generated 7652 polymorphic single nucleotide polymorphisms (SNPs) in addition to 3 KASP markers associated with known flowering genes. In total, 32 significant QTLs were identified in both landraces and modern lines. Some QTLs had a strong association with already known regulatory photoperiod genes, Ppd-A and Ppd-B, and vernalization genes Vrn-A1 and VrnA7. However, these loci explained only 5% to 20% of variance for days to heading. Seven QTLs overlapped between the two germplasm groups in which Q.ICD.Eps-03 and Q.ICD.Vrn-15 consistently affected flowering time in all the pheno-environments, while Q.ICD.Eps-09 and Q.ICD.Ppd-10 were significant only in two pheno-environments and the combined analysis across all environments. These results help clarify the genetic mechanism controlling flowering time in durum wheat and show some clear distinctions to what is known for common wheat (Triticum aestivum L.).Cellulose nanofibers, which are troublesome to spin into fibers, can be easily fabricated by post-regeneration of its acetate-derived threads. Cellulose is a natural polymer; it enjoys better biocompatibility, cellular mimicking, and hydrophilic properties than its proportionate analog. Herein, we regenerated acetate-free nanofibers by alkaline de-acetylation of as-spun nanofibers. The resultant cellulose nanofibers previously loaded with hydroxyapatite (HAp) were immobilized using silver (Ag) nanoparticles (NPs) by reduction of adsorbed Ag ions on using sodium borohydride. These amalgamated nanofibers were characterized for SEM, EDX, TEM, FTIR, and hydrophilicity tests revealing the existence of both HAp and Ag NPs in/on the nanofiber scaffolds. The de-acetylation of composite nanofibers resulted in spontaneous hydrophilicity. These nanofibers were cytocompatible, as resolved by MTT assay conducted on chicken embryo fibroblasts. The SEM of the samples after cell culture revealed that these composites allowed a proliferation of the fibroblasts over and within the nanofiber network, and increased concentration of HAp levitated the excessive of apatite formation as well as increased cell growth. The antimicrobial activity of these nanofibers was assessed on E. coli (BL21) and S. aureus, suggesting the potential of de-acetylated nanofibers to restrain bacterial growth. The degradation study for 10, 30, and 60 days indicated degradation of the fibers much is faster in enzymes as compared to degradation in PBS. The results certify that these nanofibers possess enormous potential for soft and hard tissue engineering besides their antimicrobial properties.Combination of quantum dots (QDs) and magnetic nanoparticles (MNPs) as magnetic quantum dots (MQDs) has a broad range of applications as multifunctional nanoscale devices in biological imaging, medical nano-diagnostics and nanomedicine. MQDs derived from iron oxide nanoparticles and QDs possess excellent superparamagnetic and fluorescent properties, respectively making them multifunctional nanoprobes because of their; (a) strong magnetic strength with tunable functionality, such as rapid and simple magnetic separation, (b) intense and stable fluorescence from QDs combined with tunable biological functionality upon QDs' bio-activation, and (c) imaging/visualization by simple ultraviolet light exposure. These excellent features of MQD nanoprobes enable them to be used for magnetic resonance imaging (MRI) as contrast agents, nano-diagnostic systems for Point-of-Care (PoC) disease diagnosis, theranostics nanorobots and in other bio-medical applications. Most of MQDs are derived from iron based MNPs because of their abundancy, superparamagnetic properties, low cost and easy to synthesize. In this review, we present different methods employed for chemical synthesis of MQDs derived from iron oxide MNPs, their major chemical compositions and important parameters, such as precursor compositions, quantum yield and magnetic properties. The review also summarizes the most frequently used MQDs in applications such as bio-imaging, drug delivery, biosensor platforms and finally ends with future prospects and considerations for MQDs in biomedical applications.This work describes the formulation and evaluation of a chitosan microneedle patch for the transdermal delivery of meloxicam to manage pain in cattle. Microneedle patches composed of chitosan and chitosan/meloxicam were evaluated regarding their chemical composition, uniformity of physical characteristics, capacity to penetrate the skin, and response to thermal and thermo-mechanical changes. Microneedle patches were prepared by varying the percentage of acetic acid used during solution preparation, including 90% (v/v), 50% (v/v), and 10% (v/v). In addition, drug release was assessed by modeling different percentages of penetration into the skin and the number of microneedles on the microneedle patch. Scanning electron microscopy confirmed the presence of microneedles uniformly organized on the patch surface for each percentage of acetic acid used. Fourier transform infrared spectroscopy revealed that 10% (v/v) of acetic acid in the solution was a suitable condition to preserve the characteristic bands of chitese results demonstrate that chitosan/meloxicam microneedles patches may be suitable to manage pain in cattle after routine procedures.The regenerated silk fibroin (RSF)-based microfluidic device has attracted tremendous interests in recent years due to its excellent biocompatibility, mild processing conditions, and all aqueous casting production. However, the need of a micro-fabricated mold in the manufacture process greatly hinder its practical applications. Herein, we introduce an adhesive tape-assisted etching method with LiBr solution as the etchant to prepare RSF microfluidic devices. An engraved adhesive tape is used as the mask to cover on the surface of a RSF film. Then, LiBr solution is dropped on the mask to etch RSF in concentration- and duration-dependent manners. During this process, the LiBr-treated RSF transits from insoluble β-sheet crystallites to soluble conformations. The as-prepared RSF microfluidic devices possess good chemical resistance and excellent tolerance to mechanical deformation. RSF microfluidic systems with different patterns were fabricated to demonstrate the universality of the approach. A concentration gradient generator and a blood vessel-like channel were manufactured for the preparation of solutions with gradient pHs and the growth of living cells, respectively. The proposed strategy has great potentials in the facile fabrication of low-cost RSF microfluidic devices for tissue engineering and biomedical analysis.Bacterial contamination on external wounds is known to be a factor that prevents wound healing and triggers tissue damage. Hydrogel-dressings with antibacterial activity is a useful medical device to avoid this contamination, wherein the antibacterial activity can be provided via incorporation of silver nanoparticles (AgNPs). Contrary to the conventional two-step preparation of an AgNPs-loaded hydrogel (AgNPs@hydrogel), this work aims to establish a new and facile synthesis method employing the adsorption principle. Once AgNO3 adsorbed into active sites of the hydrogels, in situ reductions using NaBH4 was employed to produce AgNPs@hydrogel. The effect of surfactant addition on the AgNO3 loading and the antibacterial activity of the resulting hydrogel dressing was investigated. The outcome of this work indicates that the addition of rarasaponin not only can increase the loading of AgNPs on cellulose carbamate hydrogel (CCH) but also significantly enhance the antibacterial activity of the resulted hydrogel-dressing. Superior to the other studied surfactant, the loading capacity (LC) of AgNPs is found to be 10.15, 9.94, and 7.53 mg/g for CCH modified with rarasaponin, CTAB, and Tween80, respectively. These findings conclude that the addition of surfactant, especially rarasaponin, can effectively improve the loading of AgNPs onto hydrogel-dressing via adsorption and promote the antibacterial activity. Furthermore, the cytotoxic test shows that the hydrogel-dressings have good biocompatibility toward skin fibroblast cells.In the present study, we fabricated an epidermal growth factor receptor (EGFR)-conjugated hydrogel to promote wound healing in cold restraint-induced gastric ulceration on burn wounds targeting collagen and inflammatory cells for the treatment of burns and gastric ulcers. Cytotoxicity and cell proliferation assays demonstrated good biocompatibility of hydrogel as a suitable extracellular matrix for targeted cells and support for regenerative cell growth. These findings were confirmed by staining methods. In vitro wound healing was confirmed cell migration in the targeted cells. The effect of the EGFR-H was investigated in cold restraint-induced gastric ulcers in rats, where the treatment was started immediately after ulcer induction. In the in vivo experiment, the EGFR-H demonstrated enhanced ulcer healing ability and less scarring compared to the hydrogel alone and controls. Thus, EGFR-H promotes healing of cold restraint-induced gastric ulcer via EGFR conjugated with a hydrogel. The present study demonstrates a novel pathway to fabricate hydrogels as suitable wound dressing biomaterials to improve deep partial thickness burn wound healing and prevent scar formation when aided by laser therapy.The Structural properties of Zinc oxide nanoparticles (ZnO-NPs) as well as their antibacterial properties against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa; as well as bacteria that are usually found in the mouth of humans and are related to dental conditions, such as Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Streptococcus mutans and Streptococcus sanguinis, are presented in this report. ZnO-NPs were grown by green synthesis, using the Mexican plant Dysphania ambrosioides known in Mexico as "epazote", which was used by native populations of Mexico as a dewormer, is currently used widely in traditional Mexican cuisine and is rich in organic compounds as flavonoids and terpenes which may favor the synthesis of nanoparticles (NPs). ZnO-NPs were synthesized by the mentioned technology and were compared with commercial ZnO-NPs as a reference. Synthesized and commercial ZnO-NPs were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray energy dispersive spectroscopy (EDS), Fourier transformed infrared spectroscopy (FTIR) and thermogravimetry (TG). Antibacterial properties were evaluated using a disc diffusion test (Kirby-Bauer method). The results indicate that ZnO-NPs were synthesized in the size range of 5-30 nm. The presence of the ZnO crystalline phase was identified by high resolution transmission electron microscopy (HRTEM) and XRD analysis. The commercial ZnO-NPs were in the size range of 15-35 nm. The antibacterial test indicates that most of the bacterial strains used in this study were sensitive to synthesized and commercial NPs, with Prevotella intermedia being the most sensitive to ZnO-NPs.In the last few decades, several natural and synthetic polymers have been used as starting material for the development of innovative polymeric nanoparticles able to encapsulate biologically active substances and to modulate their biopharmaceutical features and/or therapeutic efficacy. This investigation focused on the comparison of the physico-chemical properties of nanosystems made up of two of the most successfully used biodegradable biomaterials, namely poly(lactic-co-glycolic acid) (PLGA) and zein, belonging to the synthetic and natural family of polymers, respectively. Rutin, a polyphenolic bioflavonoid characterized by peculiar antioxidant properties, was chosen as the model drug to be encapsulated in the polymeric systems. The results demonstrated a greater ability of zein-based nanosystems to effectively retain the active compound with respect to the PLGA particles. The integration of rutin in the protein matrix favored a controlled drug leakage, and was influenced by the surfactant used to stabilize the formulation. Moreover, rutin-loaded zein nanoparticles showed significant in vitro antioxidant activity, evidencing a synergistic action between the intrinsic antioxidant activity of the protein and the pharmacological properties of the active compound. Finally, the intracellular localization of the zein nanosystems was demonstrated through confocal laser scanning microscopy.Aseptic loosening and bacterial infections are the two main causes of failure for metallic implants used for joint replacement. A coating that is both bioactive and possesses antimicrobial properties may address such shortcomings and improve the performance of the implant. We have sought to study the properties of combining hydroxyapatite-based nanoparticles or coatings with baicalein, a plant-extracted molecule with both antibacterial and antioxidant properties. (B-type) carbonated hydroxyapatite nanoparticles prepared by a chemical wet method could subsequently adsorbed by soaking in a baicalein solution. The amount of adsorbed baicalein was determined to be 63 mg.g-1 by thermogravimetric measurements. In a second approach, baicalein was adsorbed on a biomimetic calcium-deficient hydroxyapatite planar coating (12 μm thick) deposited on Ti6Al4V alloy from an aqueous solution of calcium, phosphate, sodium and magnesium salts. Soaking of the hydroxyapatite coated on titanium alloy in a baicalein solution induced partial dissolution/remodeling of the upper surface of the coating. However, the observed remodeling of the surface was much more pronounced in the presence of a baicalein solution, compared to pure water. The presence of adsorbed baicalein on the HAp layer, although it could not be precisely quantified, was assessed by XPS and fluorescence analysis. Planar coatings exhibited significant antibacterial properties against Staphylococcus epidermidis. Baicalein-modified nanoparticles exhibited significant antioxidant properties. These results illustrate the potential of hydroxyapatite used as a carrier for natural biologically-active molecules and also discuss the challenges associated with their applications as antibacterial agents.Poor water solubility, off-target toxicity, and small therapeutic window are among major obstacles for the development of drug products. Redox-responsive drug delivery nanoplatforms not only overcome the delivery and pharmacokinetic pitfalls observed in conventional drug delivery, but also leverage the site-specific delivery properties. Cleavable diselenide and disulfide bonds in the presence of elevated reactive oxygen species (ROS) and glutathione concentration are among widely used stimuli-responsive bonds to design nanocarriers. This review covers a wide range of redox-responsive chemical structures and their properties for designing nanoparticles aiming controlled loading, delivery, and release of hydrophobic anticancer drugs at tumor site.
The aim of this study was to modify the surface of fillers used in dental composites by the synthesis of two novel thiourethane oligomeric silanes, used to functionalize the silica-containing inorganic particles. Several thiourethane silane concentrations were tested during the silanization process to systematically assess the effect of silane coverage on experimental composite conversion, polymerization stress and fracture toughness.
Two different thiourethane silanes were synthesized based either on 1,6-hexanediol-diissocynate (HDDI), or 1,3-bis(1-isocyanato-1-methylethyl) benzene (BDI). Conventional 3-(Trimethoxysilyl)propyl methacrylate was used as the control. Glass fillers were silanized with 1, 2 or 4wt% of each thiourethane silane, then evaluated by thermogravimetrical analysis. Photopolymerizable resin composites were prepared with Bis-GMA/UDMA/TEGDMA and 50wt% silanized glass filler. Polymerization kinetics and degree of conversion were tested using Near-IR. Bioman was used to test polymerization stress. Data were analyzed with two-way ANOVA/Tukey's test (α=5%).
The mass of silane coupled to the filler increased with the concentrations of thiourethane in the silanizing solution, as expected. Thiourethane-containing groups exhibited significantly higher degree of conversion compared to control groups, except for BDI 4%. HDDI 4%, BDI 2% and BDI 4% showed significantly lower polymerization stress than control groups. HDDI 4% exhibited significantly higher fracture toughness.
Novel filler functionalization with thiourethane silanes may be a promising alternative for improving dental composites properties by significantly increasing the degree of conversion, fracture toughness and reducing the polymerization stress.
Novel filler functionalization with thiourethane silanes may be a promising alternative for improving dental composites properties by significantly increasing the degree of conversion, fracture toughness and reducing the polymerization stress.The very recent Covid-19 pandemic has made the need to understand biocompatible polymers as support material in drug delivery systems and controlled release clearer, especially for organo-hydrogels. This study aims to synthesize various new polymeric materials called gels, hydrogels, and organo-hydrogels according to the monomer used and to investigate their use as drug release systems. The agar-glycerol (AG) pair was used to synthesize the polymers, N, N, methylene bisacrylamide (MBA, m) and glutaraldehyde (GA, g) were used as cross-linkers and peppermint oil (PmO) was included to obtain the organo-hydrogels. Therefore, one AG gel and two p (AG-m) and p (GA-g) hydrogels were synthesized within the scope of the study. Six different organo-hydrogels based on p(AG-m-PmO) or p (AG-g-PmO) were also synthesized by varying the amount of peppermint oil. Paracetamol and carboplatin were selected as the sample drugs. Synthesized gels, hydrogels and organo-hydrogels were characterized by FTIR and SEM analysis. Addition maximum carboplatin release amount from p(AG-g-PmO) and p(AG-m-PmO) organo-hydrogels was calculated to be 99.7% at pH 7.4 and 100% at pH 7.4, respectively. It was concluded that the synthesized organo-hydrogels might easily be used as drug carrier and controlled drug release materials.Theranostic ions offer suitable platforms for cancer theranostics; here, the effect of doping various amounts of theranostic ions (i.e., Sr2+, Fe2+, and Ti4+ ions) on the physicochemical properties and biological activities of calcium phosphates (CaPs) were investigated. The solution combustion synthesis (SCS) was conducted at different amounts of ions (i.e., = 0.1, 0.25, 0.5 mol). Desirable physicochemical properties were obtained in doped samples with 0.1 mol of ions. The particle size of the Sr, Fe, and Ti-doped samples was decreased from 68 to 39, 24, and 29 nm, respectively. The surface charge of the mentioned samples was changed from -20 to -24, -28, and -25 mV, respectively. Besides, the specific surface area of the mentioned samples was significantly increased from 38 to 79, 65, and 106 m2/g, respectively. It was found that bioactivity of doped CaPs improved ~95%, which relied on the high adsorption and desorption rate of Ca2+ ions in the simulated body fluid (SBF). The in vitro cell-based results demonstrate the potent effect of CaPs and theranostic ions doped CaPs on the reactive oxygen species (ROS) generation. In the presence of CaPs, the intracellular ROS generation is increased by about 60%. Besides, the intracellular ROS generation is improved in Sr2+, Fe2+, and Ti4+ ions doped CaPs by about 66, 64, and 68%. As a result of the high generation of ROS, the bone nodule formation of cell treated CaPs and theranostic ions doped CaPs is improved 25%-37%. Finally, it can be concluded that the use of the SCS approaches for doping of theranostic ions causes well-physicochemical properties and high biological activities.Organic-inorganic composite hydrogel materials have been widely studied. In order to expand the application of organic-inorganic composite hydrogel materials, in this work, we prepared a viscous hydrogel with antibacterial properties (OSA-GelDA@ACP/DA/Ag). First, we used polydopamine coating to deposit elemental silver on the surface of amorphous calcium phosphate (ACP) particles to prepare ACP/DA/Ag particles. Next, dopamine was grafted on the gelatin molecular chain by EDC/NHS to activate the carboxyl group to obtain dopamine-modified gelatin (GelDA). The content of DA in GelDA is about 14.09% by standard curve method. Then, the Schiff base reaction took place between the amino group on the GelDA molecular chain and the aldehyde group on the OSA molecular chain, and an OSA-GelDA viscous hydrogel was prepared. Finally, by changing the content of ACP/DA/Ag3 particles added to the OSA-GelDA gel, the corresponding performance of material was investigated. The results show that the introduction of dopamine provides wet viscosity for the hydrogel, and the ACP/DA/Ag3 particles introduced in the viscous hydrogel provide antibacterial properties. This hydrogel with antibacterial and wet viscosity is expected to become an injectable bone repair material for clinical use.The aim of this work was to evaluate the expression profile of genes involved in signaling, intracellular and extracellular Ca+2 concentration and apoptosis pathways of osteoblasts in contact with a scaffold made of a composite of BCN/MWCNTs. Osteoblasts were cultivated on BCN, MWCNTs and their mixtures. Osteoblast RNA was extracted for sintering cDNA to amplify genes of interest by PCR; intra- and extracellular calcium (Ca2+) was also quantified. Regarding the genes that participate in the regulation paths (MAPK and NF-KB), it was found that only the expression of NF-KB was affected in all treatments. The expression of VEGFA increased, except in the treatment of high concentration of MWCNTs, where remained unchanged. The expression of genes Apaf-1 and Bcl-2/Bax and TP53 increased as compared to the control (except for TP53 in BC and C1/MWCNTs) indicating that cells are responding to the presence of BCN-MWCNTs composites scaffolds. The results suggest that osteoblast developed a modification in the expression profile of genes that actively participate in cellular processes such as proliferation, vasculogenesis and apoptosis, which may be modulated by the increase of intra- and extracellular Ca2+ concentration.Photothermal sterilization is a promising and effective treatment method in treating bacterial infection. Generally, a widely employed light source in photothermal sterilization inevitably damages the skin tissue due to the high-intensity irradiation dose. How to provide useful antibacterial outcomes without light-triggered skin damage is a challenge for photothermal sterilization. In this work, a novel antibacterial hydrogel (VAT hydrogel, the abbreviation for vancomycin-agarose-ferric tannate hydrogel) has been successfully constructed by the natural polysaccharide hydrogel (AG) encapsulating ferric tannate (TA-Fe) nanoparticles and vancomycin. The VAT hydrogel exhibited the outstanding photothermal properties and controllable antibiotics release. With the results of antibacterial assays, the VAT hydrogel revealed the superior effectiveness of synergistic wound disinfection by the low-intensity near-infrared light-triggered spatiotemporal antibiotics release and hyperthermia. More importantly, the VAT hydrogels possessed the good biocompatibility. With the outstanding synergistic sterilizing effect and excellent biocompatibility, the VAT hydrogel would be a promising candidate for bacteria-associated wound infections.Fast-gelling chitosan thermosensitive hydrogels have proven to be excellent matrices for targeted drug-delivery and cell therapy. In this work, we demonstrate the possibility of designing injectable bioadhesive hydrogels with a high gelation rate by modifying chitosan with catechol (cat-CH) and using sodium bicarbonate (SHC) as a gelling agent. Cat-CH/SHC hydrogels gel under 5 min at 37 °C and reach a high secant modulus after 24 h (E = 90 kPa at 50% strain). Besides, they show significantly higher adhesion to tissues than chitosan hydrogels thanks to the combination of catechol grafting and physical crosslinking. Their pH and osmolality stayed inside the physiological range. While biocompability tests will be mandatory to conclude regarding their potential for drug or cell encapsulation, these hydrogels uniquely combine physiological compatibility, injectability, fast gelation, good cohesion, and bioadhesion.Bone transplant is still the gold standard approach when dealing with orthopedic trauma or disease. When this solution is not possible, scaffolding is a possibility provided by bone tissue engineering. To support the regeneration process, damaged bone tissue is removed and replaced by porous scaffold structures. In recent years, additive manufacturing has shown huge potential to produce scaffold structures with the required performance. In the current work, PLA scaffolds with different designs were 3D printed, using optimal manufacturing parameters. Scaffolds with three different porosity values were obtained by changing the filament offset from 571 to 1333 μm. A total of twelve designs were tested under monotonic and dynamic compression conditions. Numerical analysis showed good correlation with experimental results, allowing for a better assessment of scaffold mechanical behavior. Stress relaxation was measured on four different strain levels, assessing scaffold's behavior after implantation and consequent static response over time.
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