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Current biofabrication strategies are limited in their ability to replicate native shape-to-function relationships, that are dependent on adequate biomimicry of macroscale shape as well as size and microscale spatial heterogeneity, within cell-laden hydrogels. In this study, a novel diffusion-based microfluidics platform is presented that meets these needs in a two-step process. In the first step, a hydrogel-precursor solution is dispersed into a continuous oil phase within the microfluidics tubing. By adjusting the dispersed and oil phase flow rates, the physical architecture of hydrogel-precursor phases can be adjusted to generate spherical and plug-like structures, as well as continuous meter-long hydrogel-precursor phases (up to 1.75 m). The second step involves the controlled introduction a small molecule-containing aqueous phase through a T-shaped tube connector to enable controlled small molecule diffusion across the interface of the aqueous phase and hydrogel-precursor. Application of this system is demonstrated by diffusing co-initiator sodium persulfate (SPS) into hydrogel-precursor solutions, where the controlled SPS diffusion into the hydrogel-precursor and subsequent photo-polymerization allows for the formation of unique radial stiffness patterns across the shape- and size-controlled hydrogels, as well as allowing the formation of hollow hydrogels with controllable internal architectures. Mesenchymal stromal cells are successfully encapsulated within hollow hydrogels and hydrogels containing radial stiffness gradient and found to respond to the heterogeneity in stiffness through the yes-associated protein mechano-regulator. Finally, breast cancer cells are found to phenotypically switch in response to stiffness gradients, causing a shift in their ability to aggregate, which may have implications for metastasis. The diffusion-based microfluidics thus finds application mimicking native shape-to-function relationship in the context of tissue engineering and provides a platform to further study the roles of micro- and macroscale architectural features that exist within native tissues.

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BACKGROUND: Single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is widely used to identify ischemia. There is limited research to evaluate if there is a risk threshold below which SPECT-MPI may not add significant prognostic value. METHODS: Between January 1, 2012, and December 31, 2018, individuals who underwent SPECT-MPI were stratified into 4 risk groups. The primary outcome was acute myocardial infarction (MI) or death. Multivariable Cox proportional hazards regression analysis was used to calculated hazard ratios (HRs) with 95% confidence intervals (CIs). RESULTS: Among 48,845 patients (52.3% male, median age 67 years), 8.5% were low risk, 4.8% borderline risk, 18.1% intermediate risk, and 68.6% high risk based on the American College of Cardiology pooled cohort equation. Ischemia was more commonly detected in the high-risk cohort (19.4% in high-risk vs 6.5% in low-risk). SPECT-MPI testing was associated with a significantly increased use of preventive medications such as statin therapy, regardless of stress test results. At a median follow-up of 4.2 years, there was no significant association between ischemia and death or MI in the low-risk cohort (adjusted HR, 1.91; 95% CI, 0.94-3.92) or the borderline-risk cohort (adjusted HR, 1.58; 95% CI, 0.79-3.15). Ischemia was associated with a higher risk of death or MI in the intermediate-risk (adjusted HR, 1.57; 95% CI, 1.24-1.99) and high-risk groups (adjusted HR, 1.54; 95% CI, 1.44-1.64). CONCLUSIONS: SPECT-MPI was less useful for risk stratification among low-risk patients because of their low event rates regardless of test results.

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The catalytic application of 3-(4-sulfobutyl)-1H-imidazole-3-ium chloride immobilized on activated silica gel (SiO2-Imi-SO3H) for the production of 5-hydroxymethylfurfural is described here for the first time. This material was synthesized using a three-step method involving the grafting of chloropropyl groups onto activated silica gel, the substitution of zwitterions, and the acidification of zwitterions to form silica-supported ionic liquid. The successful immobilization of the IL on silica gel was confirmed through energy-dispersive X-ray (EDX) spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and elemental mapping. SiO2-Imi-SO3H-2 demonstrated good catalytic activity and recycling ability in fructose dehydration to 5-HMF. Several conditions for reaction were investigated, and an excellent 5-HMF yield (94.1%) was obtained after 4 h at 160 °C in dimethyl sulfoxide (DMSO) from fructose. Furthermore, a mechanism was proposed, the catalyst's reusability was investigated, and the catalyst was applied for the conversion of glucose to 5-HMF with other metal salts.

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Microcarrier expansion systems show exciting potential to revolutionise mesenchymal stromal cell (MSC)-based clinical therapies by providing an opportunity for economical large-scale expansion of donor- and patient-derived cells. The poor reproducibility and efficiency of cell expansion on commercial polystyrene microcarriers have driven the development of novel microcarriers with tuneable physical, mechanical, and cell-instructive properties. These new microcarriers show innovation toward improving cell expansion outcomes, although their limited biological characterisation and compatibility with dynamic culture systems suggest the need to realign the microcarrier design pathway. Clear headway has been made toward developing infrastructure necessary for scaling up these technologies; however, key challenges remain in characterising the wholistic effects of microcarrier properties on the biological fate and function of expanded MSCs.

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A synergistic multilayer membrane design is necessary to satisfy a multitude of requirements of an ideal wound dressing. In this study, trilayer dressings with asymmetric wettability, composed of electrospun polycaprolactone (PCL) base membranes coated with oligomer chitosan (COS) in various concentrations of polyvinylpyrrolidone (PVP), are fabricated for wound dressing application. The membranes are expected to synergize the hygroscopic, antibacterial, hemostatic, and biocompatible properties of PCL and COS. The wound dressing was coated by spraying the solution of 3% COS and 6% PVP on the PCL base membrane (PVP6-3) three times, which shows good interaction with biological subjects, including bacterial strains and blood components. PVP6-3 samples confirm the diameter of inhibition zones of 20.0 ± 2.5 and 17.9 ± 2.5 mm against Pseudomonas aeruginosa and Staphylococcus aureus, respectively. The membrane induces hemostasis with a blood clotting index of 74% after 5 min of contact. In the mice model, wounds treated with PVP6-3 closed 95% of the area after 10 days. Histological study determines the progression of skin regeneration with the construction of granulation tissue, new vascular systems, and hair follicles. Furthermore, the newly-growth skin shares structural resemblances to that of native tissue. This study suggests a simple approach to a multi-purpose wound dressing for clinical treatment.

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Although some studies on the effects of para-probiotics on the immune system and intestinal health have been conducted independently of research on antibiotics ass growth promoters. This study investigated the effects of heat-killed Lactobacillus plantarumL-137 (L-137) and antibiotics as preventive and/or therapeutic substances for broilers against subclinical necrotic enteritis caused by Clostridium perfringens (CP). In total, 300 1-day-old broilers (46.13 ± 1.38 g) were randomly stocked at 10 birds pen-1 in five replicates and divided into six groups, namely T1 and T2, positive and negative control of CP challenge; T3 and T4, prevention with basal diet plus 10 and 50 mg/kg L-137; T5 and T6, prevention and treatment with basal diet plus 50 mg/kg of L-137 and bacitracin at 50 ppm, respectively. Broilers administered L-137 in T4, T5 and bacitracin in T6 showed an improved (p < 0.05) villus height/crypt depth ratio than control groups, suggesting that it might significantly boost growth performance. In contrast to bacitracin, a high dosage of L-137 significantly increased (p < 0.05) the spleen index value and the cytokine levels, as well as the expression of intestinal ß-defensin genes on day 28. During the 42-day production period, broilers in T4 and T5 showed a significantly enhanced (p < 0.05) expression of cytokines, AvBD-1 and AvBD-7 on day 42 compared to the control and bacitracin groups. In particular, broilers given the L-137 diets demonstrated no cumulative mortality following CP exposure, compared to a 2% mortality in T6. Our findings provide insight into eco-friendly alternatives to antibiotics for maximizing growth performance, feed efficiency and long-term disease protection in chickens; however, this has to be proven in larger-scale commercial experiments.

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The use of naturally occurring materials with antibacterial properties has gained a great interest in infected wound management. Despite being an abundant resource in Vietnam, chitosan and its derivatives have not yet been intensively explored for their potential in such application. Here, we utilized a local chitosan source to synthesize chitosan oligomers (OCS) using hydrogen peroxide (H2O2) oxidation under the microwave irradiation method. The effects of H2O2 concentration on the physicochemical properties of OCS were investigated through molecular weight, degree of deacetylation, and heavy metal contamination for optimization of OCS formulation. Then, the antibacterial inhibition was examined; the minimum inhibitory concentration and minimum bactericidal concentration (MIC and MBC) of OCS-based materials were determined against common skin-inhabitant pathogens. The results show that the local Vietnamese chitosan and its derivative OCS possessed high-yield purification while the molecular weight of OCS was inversely proportional and proportional to the concentration of H2O2, respectively. Further, the MIC and MBC of OCS ranged from 3.75 to less than 15 mg/mL and 7.5-15 mg/mL, respectively. Thus, OCS-based materials induce excellent antimicrobial properties and can be attractive for wound dressings and require further investigation.

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The aim of this study was to evaluate the protective efficacy of the CIRCOQ porcine circovirus type 2 (PCV2) subunit vaccine in piglets with high maternally derived antibodies (MDAs) against disease caused by natural infection with PCV2d. A total of 130 weaned, 21-day-old healthy pigs was allocated into 3 trial groups. The signs of respiratory disorder were higher in unvaccinated pigs than in vaccinated pigs at 13 to 17 weeks old (P < 0.05), 18 to 22 weeks old (P < 0.001), and 23 to 27 weeks old (P < 0.01). The unvaccinated pigs had an early rate of dermatitis at 8 to 12 weeks old (10.0%), 13 to 17 weeks old (30.0%), 18 to 22 weeks old (46.7%), and 23 to 27 weeks old (33.3%), while there were no cases of dermatitis in vaccinated pigs. There was a significant difference (P < 0.05) in the mortality of pigs in the unvaccinated group and the 2-dosed vaccinated group. PCV2 viremia was detected in the blood and peaked at 105 days old in both unvaccinated pigs (Ct-adj = 8.40) and pigs vaccinated with 1 dose (Ct-adj = 6.37), while no detectable PCV2 virus was found in the blood of pigs vaccinated with 2 doses. At 77 and 105 days old, the PCV2 viremia load (Ct-adj) of unvaccinated pigs and those vaccinated with 1 dose was significantly higher (P < 0.05) than that of the 2-dosed vaccinated pigs. The body weight (BW), average weight gain (AWG), and average daily gain (ADG) in both groups of vaccinated pigs were significantly higher (P < 0.05) than those of unvaccinated pigs. The study vaccine was significantly efficacious in protecting vaccinated pigs against clinical symptoms, blood viral load, and mortality, as well as improving productivity, compared with unvaccinated pigs.

Le but de la présente étude était d'évaluer l'efficacité protectrice du vaccin sous-unitaire CIRCOQ du circovirus porcin de type 2 (PCV2) chez les porcelets ayant une grande quantité d'anticorps d'origine maternelle (MDA) contre la maladie causée par une infection naturelle par le PCV2d. Un total de 130 porcs sains sevrés âgés de 21 jours a été réparti dans trois groupes d'essai. Les signes de troubles respiratoires étaient plus élevés chez les porcs non vaccinés que chez les porcs vaccinés âgés de 13 à 17 semaines (P < 0,05), de 18 à 22 semaines (P < 0,001) et de 23 à 27 semaines (P < 0,01). Les porcs non vaccinés avaient un taux précoce de dermatite entre 8 et 12 semaines (10,0 %), 13 à 17 semaines (30,0 %), 18 à 22 semaines (46,7 %) et 23 à 27 semaines (33,3 %), alors qu'il n'y a eu aucun cas de dermatite chez les porcs vaccinés. Il y avait une différence significative (P < 0,05) dans la mortalité des porcs dans le groupe non vacciné et le groupe vacciné à deux doses. La virémie du PCV2 a été détectée dans le sang et a atteint un pic à 105 jours chez les porcs non vaccinés (Ct-adj = 8,40) et les porcs vaccinés avec une dose (Ct-adj = 6,37), tandis qu'aucun virus PCV2 détectable n'a été détecté dans le sang des porcs vacciné avec deux doses. À 77 et 105 jours, la charge de virémie PCV2 (Ct-adj) des porcs non vaccinés et de ceux vaccinés avec une dose était significativement plus élevée (P < 0,05) que celle des porcs vaccinés à deux doses. Le poids corporel (BW), le gain de poids moyen (AWG) et le gain quotidien moyen (ADG) dans les deux groupes de porcs vaccinés étaient significativement plus élevés (P < 0,05) que ceux des porcs non vaccinés. Le vaccin de l'étude s'est avéré significativement efficace pour protéger les porcs vaccinés contre les symptômes cliniques, la charge virale sanguine et la mortalité, ainsi que pour améliorer la productivité, par rapport aux porcs non vaccinés.(Traduit par Docteur Serge Messier).

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Wound dressings are typically used to provide a favorable environment supporting the intricate process of wound healing. This research aims to fabricate and evaluate an electrospun polycaprolactone (EsPCL) membrane coated with various densities of chitosan oligomers (COS) - a biological agent - for application as bioactive wound dressing. Weight calculation was employed to investigate the density of COS coated onto the electrospun PCL membrane. Physicochemical characteristics of the prepared membranes, such as hydrophilicity and mechanical properties were demonstrated and evaluated through standard experimental methods. In vitro assays and mice model were used to investigate the antibacterial activities, cytocompatibility, hemostasis and the in vivo interaction of the membranes. The results showed that COS was coated successfully on the surface of the polymeric membrane, altering its morphology and associated characteristics. The greater concentration of COS led to an increase in the thickness of the membrane, which resulted in stronger antibacterial activities. Moreover, the increase of chitosan oligomers density in the membrane induced faster hemostasis and affected the re-epithelialization and wound healing in mice. Thus, the membrane as a whole and particularly chitosan oligomers were shown to be potential for further studies regarding wound dressing.

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Two studies were conducted to evaluate the effects of dietary supplementation of guanidinoacetic acid (GAA) on growth performance, carcass characteristics, and meat quality in pigs from wean to finish (Exp 1) and finishing pigs fed GAA at different time periods before slaughter (Exp 2). In Exp 1, a total of 360 weaned pigs (Duroc × [Landrace × Yorkshire]) with an average initial BW of 7.17 ± 0.03 kg were randomly distributed into 3 dietary treatments consisting of 10 replicates per treatment and 12 pigs (6 barrows and 6 gilts) per replicate. Dietary treatments were a control (CON; basal diet), a basal diet + 0.08% GAA (0.08% GAA); and a basal diet + 0.12% GAA (0.12% GAA). The duration of the experiment was 150 d. At the end of the experiment, 20 pigs (10 barrows and 10 gilts) from each treatment were slaughtered for measuring carcass characteristics and meat quality. In Exp 2, 1,440 finishing pigs [(Duroc × (Landrace × Yorkshire)), 56.15 ± 0.10 kg BW)] were randomly allocated to 4 treatments with 18 replicates (20 pigs per replicate). Dietary treatments were a control diet (CON; basal), a basal diet + 0.12% GAA fed 60 d before slaughter (T1), a basal diet + 0.12% GAA fed 40 d before slaughter (T2), and a basal diet + 0.12% GAA fed 25 d before slaughter (T3). Body weight was measured at the start (120 d of age) and at the end (180 d of age) of the experiment. At the end of the study, 144 pigs (72 barrows and 72 gilts) from 4 dietary treatments (36 pigs per treatment) were slaughtered for the determination of carcass and meat quality parameters. In Exp 1, 0.12 % GAA increased (P < 0.05) ADG and G:F during starter, grower, finisher, and the overall growth period (30 to 180 d of age). Pigs fed 0.12 % GAA had improved (P < 0.05) lean meat yield in comparison with CON. There was no interaction effect among GAA supplementation and sex of the pigs. Meat quality was not affected by GAA supplementation in pigs. In Exp 2, the final BW, ADG, and lean yield of the pigs fed T1 were higher (P < 0.05) than CON and those fed T3. The carcass back-fat thickness of T1 was lower (P < 0.05) than CON. In conclusion, 0.12% GAA improved the growth performance and lean meat yield in pigs from wean to finish. Finishing pigs fed diets supplemented with 0.12% GAA 60 d before slaughter improved ADG, feed efficiency, and lean meat yield and reduced back-fat thickness compared with those fed GAA unsupplemented diets.

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Cells maintain integrity despite changes in their mechanical properties elicited during growth and environmental stress. How cells sense their physical state and compensate for cell-wall damage is poorly understood, particularly in plants. Here we report that FERONIA (FER), a plasma-membrane-localized receptor kinase from Arabidopsis, is necessary for the recovery of root growth after exposure to high salinity, a widespread soil stress. The extracellular domain of FER displays tandem regions of homology with malectin, an animal protein known to bind di-glucose in vitro and important for protein quality control in the endoplasmic reticulum. The presence of malectin-like domains in FER and related receptor kinases has led to widespread speculation that they interact with cell-wall polysaccharides and can potentially serve a wall-sensing function. Results reported here show that salinity causes softening of the cell wall and that FER is necessary to sense these defects. When this function is disrupted in the fer mutant, root cells explode dramatically during growth recovery. Similar defects are observed in the mur1 mutant, which disrupts pectin cross-linking. Furthermore, fer cell-wall integrity defects can be rescued by treatment with calcium and borate, which also facilitate pectin cross-linking. Sensing of these salinity-induced wall defects might therefore be a direct consequence of physical interaction between the extracellular domain of FER and pectin. FER-dependent signaling elicits cell-specific calcium transients that maintain cell-wall integrity during salt stress. These results reveal a novel extracellular toxicity of salinity, and identify FER as a sensor of damage to the pectin-associated wall.

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The minD gene encoding an inhibitor cell division MinD homolog from Lactobacillus acidophilus VTCC-B-871 was cloned. We showed that there were 97 % homology between minD genes of L. acidophilus VTCC-B-871 and Lactobacillus rhamnosus GG and Lactobacillus rhamnosus Lc705. Based on the analysis of the DNA sequence data from the L. rhamnosus genome project and sequenced minD gene of L. acidophilus VTCC-B-871, a pair of primers was designed to identified the different minD genes from L. acidophilus ATCC 4356, L. rhamnosus ATCC 11443. Besides, the polymerase chain reaction product of minD gene was also obtained in L. rhamnosus PN04, a strain was isolated from Vietnamese Hottuynia cordata Thunb. In addition, we performed a phylogenetic analysis of the deduced amino acid sequence of MinD homologs from L. acidophilus VTCC-B-871 with the other strains and compared the predicted three-dimension structure of L. acidophilus VTCC-B-871 MinD with Escherichia coli MinD, there are similarity that showed evolution of these strains. The overexpression of L. acidophilus VTCC-B-871 MinD in E. coli led to cell filamentation in IPTG and morphology changes in different sugar stresses, interestingly. The present study is the first report characterizing the Lactobacilus MinD homolog that will be useful in probiotic field.