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1.
Artigo em Inglês | MEDLINE | ID: mdl-36098912

RESUMO

Developing efficient and cost-effective non-noble metal catalysts for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) is of great importance. Herein, Co-promoted 1T-MoS2 nanoflowers were synthesized via a one-step hydrothermal method. The influence of Co content on the structure and catalytic performance of 1T-MoS2 was studied in detail. It was found that Co doping not only enhanced the electronic conductivity but also increased the hydrogen adsorption ability of 1T-MoS2. Meanwhile, the highest activity was achieved due to the synergy effect of Co-Mo-S and CoS2 active phase. In the catalytic reduction of 4-NP, the reaction rate constant of Co/1T-MoS2-0.3 was as high as 0.908 min-1 and the catalyst exhibited excellent stability after recycling five times. The present work provides new insights for the rational design of highly efficient metal-doped MoS2 catalysts towards 4-NP reduction in wastewater.

2.
J Food Sci ; 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36120929

RESUMO

Phosvitin (PV) is the main phosphoprotein in egg yolk, with the highest degree of phosphorylation known in nature. The PV and resveratrol (Res) can form a complex, thus effectively improve the solubility of Res. In this work, the interaction between Res and PV was investigated by the fluorescence spectroscopy and molecular docking. The fluorescence emission intensity of PV became weak along with a red shift when it interacted with Res and the antioxidant activity was enhanced. The quenching constants of the interaction systems were 1.12×104  M-1 and 9.40×103  M-1 at 25°C and 35°C, respectively, which indicated the presence of static quenching phenomena between them. The binding constant was 1.80×104  M-1 , and the number of corresponding binding sites was approximately equal to one. The thermodynamic results revealed the combination was spontaneous, and the change of enthalpy and entropy was ∆H = 53.50 kJ/mol, ∆S = 261.00 J/mol·K, respectively. It indicated that the interaction forces between Res and PV were mainly hydrophobic interaction and hydrogen bonding. Molecular docking showed the binding mode, which was consistent with the experiment results. The research on the interaction between Res and PV provided theoretical guidance for the application of Res in food. PRACTICAL APPLICATION: PV is the most highly phosphorylated protein in nature and has pro-calcium absorption effects. Res is a polyphenol with strong antioxidant and anti-inflammatory activity, but its poor solubility limits its application. In this study, the solubility of Res was considerably enhanced by compounding Res and PV, and the antioxidant activity of Res was well retained. It increases the value of Res in food and other applications and opens up new possibilities for processing and utilization of PV.

3.
HPB (Oxford) ; 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36127226

RESUMO

BACKGROUND: Routine lymphadenectomy in pancreatic neuroendocrine tumors (pNETs) is debated. There lacks accurate model to predict lymph node metastasis (LNM) preoperatively in pNETs. Therefore, this study aimed at developing a nomogram in predicting LNM in pNETs preoperatively. METHODS: Patients undergoing surgery from Surveillance, Epidemiology, and End Results (SEER) database (design cohort, n = 2742) and First Affiliated Hospital of Sun Yat-sen University (validation cohort, n = 136) were enrolled. Nomogram was developed based on risk factors determined by logistic regression analyses. The performance of nomogram was evaluated by area under receiver operating characteristics curve (AUC), calibration curve, and decision curve analysis. RESULTS: In design cohort, 915 of 2742 patients had LNM. Tumor in the pancreatic head, T stage, and tumor size were significantly associated with LNM (all p < 0.05). Prediction of nomogram was accurate with AUC of 0.776 in design cohort and 0.622 in validation cohort. The nomogram showed good agreement between prediction and observation in the design and validation cohort. Based on nomogram-predicted risk, patients with higher risk of LNM had worse overall survival over patients with lower risk of LNM (log-rank p < 0.001). CONCLUSIONS: The novel nomogram could accurately predict LNM in pNET preoperatively. For patients with high risk of LNM, lymphadenectomy was recommended.

4.
Tissue Eng Part A ; 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36047505

RESUMO

Bioelectronics presents a promising future in the field of embedded and implantable electronics, providing a range of functional applications, from personal health monitoring to bioactuators. However, due to the intrinsic difficulties present in producing and optimising bioelectronics, recent research has focused on utilising Machine Learning to reliably mitigate such issues and aid in process development. This review focuses on the recent developments of integrating Machine Learning into bioelectronics, aiding in a multitude of areas such as: material development, fabrication process optimisation and system integration. First, discussing how Machine Learning has aided in the materials development by identifying complex relationships between process input parameters and desired outputs, such as product design. Second, examine the advancements in Machine Learning to accurately optimise fabrication precision and stability for various 3D printing technologies. Third, provide an overview of how Machine Learning can greatly assist in the analysis of complex, non-linear relationships in data obtained from bioelectronics. Lastly, a summary of the challenges present with utilising Machine Learning with bioelectronics and any other developments in this field. Such advancements in the field of bioelectronics and Machine Learning could hopefully build a strong foundation for this research field, promoting smart optimisation together with effective use of Machine Learning to further enhance the effectiveness of such applications.

5.
Sensors (Basel) ; 22(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36081071

RESUMO

Wankel pump designs have not been fully established, with existing designs limited to bicornous rotor pumps and triangular rotor pumps. Here, on the basis of Wankel geometry, we present a tetragonal rotor pump with a three-lobe epicycloid and its conjugate envelope as chamber and rotor profile. First, the design method and basic working principle of the pump are introduced. Four groups of prototypes with different shape factors were manufactured, and their flow and pressure characteristics were experimentally studied. Numerical study showed that the flow rate irregularity of the pump is lower than that of existing Wankel pumps. Finally, the feasibility the pump for mixing applications was verified by a flow field observation experiment. The work in this paper provides a new type of rotary displacement pump design, representing an study of reverse application of a Wankel engine structure.

6.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142189

RESUMO

Migratory birds spend several months in their breeding grounds in sympatry with local resident birds and relatively shorter periods of time at stopover sites. During migration, parasites may be transmitted between migratory and resident birds. However, to what extent they share these parasites remains unclear. In this study, we compared the assemblages of haemosporidian parasites in migratory, resident, and passing birds, as well as the correlations between parasite assemblages and host phylogeny. Compared with passing birds, migratory birds were more likely to share parasites with resident birds. Shared lineages showed significantly higher prevalence rates than other lineages, indicating that common parasites are more likely to spill over from the current host to other birds. For shared lineages, the prevalence was significantly higher in resident birds than in migratory birds, suggesting that migratory birds pick up parasites at their breeding ground. Among the shared lineages, almost two-thirds presented no phylogenetic signal in their prevalence, indicating that parasite transmission among host species is weakly or not correlated with host phylogeny. Moreover, similarities between parasite assemblages are not correlated with either migration status or the phylogeny of hosts. Our results show that the prevalence, rather than host phylogeny, plays a central role in parasite transmission between migratory and resident birds in breeding grounds.

7.
Plant Commun ; : 100433, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071669

RESUMO

To expand crop planting areas, crop latitude adaptation re-establishment based on genetic variation in photoperiodic genes can be carried out but is quite time-consuming. On the contrary, a crop variety that already has multi-latitude adaptation has the potential to increase its planting areas to be more widely and quickly available. However, the importance and potential of crop variety multiple-latitude adaptation have not been systematically described. Here, combining the daylength sensing data with the cropping system of the elite rice and maize varieties, we found that the varieties with gradual daylength sensing coupled with optimum cropping modes have enhanced capacity for multi-latitude adaptation in China. Further, this multi-latitude adaptation expanded their planting areas and indirectly improved China's rice and maize nationwide unit yield. Thus, coupling the daylength sensing process with optimum cropping modes to enhance latitude adaptability of excellent varieties represents an exciting approach to deploy crop varieties with the potential to expand their planting areas and quickly improve crop nationwide unit yield in developing countries.

8.
Plant Commun ; : 100428, 2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36065466

RESUMO

Plant UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8) exists as a homodimer in its inactive ground state. Upon UV-B exposure, UVR8 monomerizes and interacts with a downstream key regulator CONSTITUTIVE PHOTOMORPHOGENIC 1/SUPPRESSOR OF PHYA (COP1/SPA) E3 ubiquitin ligase complex to initiate UV-B signaling. Two WD40 proteins, REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1 (RUP1) and RUP2 directly interact with monomeric UVR8 and facilitate UVR8 ground state reversion, completing the UVR8 photocycle. Here, we reconstituted the RUP-mediated UVR8 redimerization process in vitro and reported the structure of the RUP2-UVR8W285A complex (2.0 Å). RUP2 and UVR8W285A formed a heterodimer via two distinct interfaces, designated Interface 1 and 2. The previously characterized Interface 1 is found between RUP2 WD40-domain and UVR8 C27-subregion. The newly identified Interface 2 is formed through the interactions between RUP2 WD40-domain and UVR8 core domain. Disruption of Interface 2 impaired UV-B induced photomorphogenic development in Arabidopsis thaliana. Further biochemical analysis indicated that both interfaces are important for RUP2-UVR8 interactions and the RUP2-mediated facilitation of UVR8 redimerization. Our findings suggest that the two-interface-interaction mode is adopted by both RUP2 and COP1 when interact with UVR8, and mark a step forward in understanding the molecular basis underpinning the interactions between UVR8 and its photocycle regulators.

9.
Food Sci Biotechnol ; 31(10): 1243-1256, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35992319

RESUMO

Egg yolk contains very high levels of lipids, which comprise 33% of whole egg yolk. Although triglyceride is the main lipid, egg yolk is the richest source of phospholipids and cholesterol in nature. The egg yolk phospholipids have a unique composition with high levels of phosphatidylcholine followed by phosphatidylethanolamine, sphingomyelin, plasmalogen, and phosphatidylinositol. All the egg yolk lipids are embedded inside the HDL and LDL micelles or granular particles. Egg yolk lipids can be easily extracted using solvents or supercritical extraction methods but their commercial applications of egg yolk lipids are limited. Egg yolk lipids have excellent potential as a food ingredient or cosmeceutical, pharmaceutical, and nutraceutical agents because they have excellent functional and biological characteristics. This review summarizes the current knowledge on egg yolk lipids' extraction methods and functions and discusses their current and future use, which will be important to increase the use and value of the egg.

10.
Foods ; 11(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36010434

RESUMO

Chicken egg whites contain hundreds of proteins, and are widely used in the food, biological and pharmaceutical industries. It is highly significant to study the separation and purification of egg white proteins. This review first describes the structures and functional properties of several major active proteins in egg whites, including ovalbumin, ovotransferrin, ovomucoid, lysozyme, ovomucin, ovomacroglobulin and avidin. Then, the common techniques (including precipitation, chromatography and membrane separation) and some novel approaches (including electrophoresis, membrane chromatography, aqueous two-phase system and molecular imprinting technology) for the separation and purification of egg white proteins broadly reported in the current research are introduced. In addition, several co-purification methods for simultaneous separation of multiple proteins from egg whites have been developed to improve raw material utilization and reduce costs. In this paper, the reported techniques in the last decade for the separation and purification of chicken egg white proteins are reviewed, discussed and prospected, aiming to provide a reference for further research on egg proteins in the future.

11.
Plant Biotechnol J ; 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36028476

RESUMO

Self-transcribing active regulatory region sequencing (STARR-seq) is widely used to identify enhancers at the whole-genome level. However, whether STARR-seq works as efficiently in plants as in animal systems remains unclear. Here, we determined that the traditional STARR-seq method can be directly applied to rice (Oryza sativa) protoplasts to identify enhancers, though with limited efficiency. Intriguingly, we identified not only enhancers but also constitutive promoters with this technique. To increase the performance of STARR-seq in plants, we optimized two procedures. We coupled fluorescence activating cell sorting (FACS) with STARR-seq to alleviate the effect of background noise, and we minimized PCR cycles and retained duplicates during prediction, which significantly increased the positive rate for activating regulatory elements (AREs). Using this method, we determined that AREs are associated with AT-rich regions and are enriched for a motif that the AP2/ERF family can recognize. Based on GC content preferences, AREs are clustered into two groups corresponding to promoters and enhancers. Either AT- or GC-rich regions within AREs could boost transcription. Additionally, disruption of AREs resulted in abnormal expression of both proximal and distal genes, which suggests that STARR-seq-revealed elements function as enhancers in vivo. In summary, our work provides a promising method to identify AREs in plants.

12.
Front Neurol ; 13: 930753, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35968313

RESUMO

Purpose: Stomach 36 (ST36, zusanli) is one of the important acupoints in acupuncture. Despite clinical functional magnetic resonance imaging (fMRI) studies of ST36 acupuncture, the brain activities and the neural mechanism following acupuncture at ST36 remain unclear. Methods: Literature searches were conducted on online databases, including MEDLINE, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wanfang database, WeiPu database, and China Biology Medicine, for task-based fMRI studies of acupuncture at ST36 in healthy subjects. Brain regions activated by ST36 acupuncture were systematically evaluated and subjected to seed-based d mapping meta-analysis. Subgroup analysis was conducted on control procedures, manual acupuncture, electrical acupuncture (EA), and acupuncture-specific activations. Meta-regression analysis was performed to explore the effects of needle retention time on brain activities following ST36 acupuncture stimulation. The activated brain regions were further decoded and mapped on large-scale functional networks to further decipher the clinical relevance of acupuncturing at ST36. Results: A total of sixteen studies, involving a total of 401 right-handed healthy participants, that satisfied the inclusion criteria were included in the present meta-analysis. Meta-analysis showed that acupuncturing on ST36 positively activates the opercular part of the right inferior frontal gyrus (IFG.R), left superior temporal gyrus (STG.L), and right median cingulate/paracingulate gyri (MCG.R) regions. Needle retention time in an acupuncture session positively correlates with the activation of the left olfactory cortex, as shown in meta-regression analysis. Subgroup analysis revealed that EA stimulation may be a source of heterogeneity in the pooled results. Functional network mappings showed that the activated areas were mapped to the auditory network and salience network. Further functional decoding analysis showed that acupuncture on ST36 was associated with pain, secondary somatosensory, sound and language processing, and mood regulation. Conclusion: Acupuncture at ST36 in healthy individuals positively activates the opercular part of IFG.R, STG.L, and MCG.R. The left olfactory cortex may exhibit positive needle retention time-dependent activities. Our findings may have clinical implications for acupuncture in analgesia, language processing, and mood disorders. Systematic Review Registration: https://inplasy.com/inplasy-2021-12-0035.

13.
Poult Sci ; 101(10): 102053, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35986946

RESUMO

The objective of this study was to compare the immunomodulatory effects of the chicken soups prepared with the native free-range chickens and the commercial caged broilers in the immunosuppressive mice. The immunosuppressive mice model was established by the intraperitoneal injection of 100 mg of cyclophosphamide (CTX) per kg body weight. The powders of Gushi Chicken Soup (GCS), Honglashan Chicken Soup (HCS), and Cobb Broiler Soup (CBS) were prepared by high-pressure stewing followed by spray drying. The chicken soups' nutrient content and the effects of three chicken soups on the body weight, organ index, blood index, and serum cytokine and immunoglobulin contents in the immunosuppressive mice were determined. The three chicken soups promoted the recovery of immunosuppressive mice, but the expression mechanisms were different. The GCS was more effective than the HCS and CBS in restoring blood index, promoting cytokine secretion, and increasing immunoglobulin content (P < 0.05). The HCS stimulated the Th1-type immune response and promoted immunoglobulin secretion (P < 0.05), while the CBS increased the production of CD4+ and promoted the T-cell functions better than other soups (P < 0.05). Although soups from the native free-range chickens and the commercial caged broilers showed distinctly different mechanisms in promoting immunity, both could be used as potential immunomodulators.

14.
Artigo em Chinês | MEDLINE | ID: mdl-35959586

RESUMO

Chronic sinusitis (CRS) is one of the most common nasal diseases, and FSDP is a risk factor for CRS. The variation of the frontal recess cell obstructs the frontal sinus drainage pathway, which makes the frontal sinus surgery more difficult and a higher recurrence rate than other sinus surgeries. Therefore, before surgery, a thin-slice CT scan is performed on the patient to fully evaluate the anatomical structure and drainage pathway of the frontal sinus, and to understand the variation of FSDP cell is crucial for accurate opening of the frontal sinus. In this paper, A case of large supra bulla frontal cell infection was summarized and analyzed. The anatomical structure of the frontal recess was fully understood by preoperative radiographs, the spatial relationship between the cells was identified, and the appropriate surgical plan was developed, which was beneficial for the surgeon to accurately open the frontal cortex during surgery and avoid postoperative recurrence.


Assuntos
Seio Frontal , Sinusite Frontal , Sinusite , Vesícula , Doença Crônica , Endoscopia , Seio Frontal/cirurgia , Sinusite Frontal/cirurgia , Humanos , Tomografia Computadorizada por Raios X
15.
Pharm Biol ; 60(1): 1520-1532, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35952388

RESUMO

CONTEXT: Asthma is a common respiratory system disease. Louki Zupa decoction (LKZP), a traditional Chinese medicine, presents a promising efficacy against lung diseases. OBJECTIVE: To investigate the pathogenic mechanism of asthma and reveal the intervention mechanism of LKZP. MATERIALS AND METHODS: Forty-eight female Balb/c mice were randomly divided into 6 groups: normal control group (NC), ovalbumin (OVA)/saline asthma model group, OVA/LL group, OVA/LM group, OVA/LH group and OVA/DEX group (n = 8 per group). The asthmatic mice were modelled through intraperitoneal injecting and neutralizing OVA. LKZP decoction was administrated by gavage at the challenge stage for seven consecutive days (2.1, 4.2 and 8.4 g/kg/day). We investigated the change in lung function, airway inflammation, mucus secretion and TH-1/TH-2-related cytokines. We further verify the activated status of the IL-33/ST2/NF-κB/GSK3ß/mTOR signalling pathway. RESULTS: LKZP was proved to improve asthmatic symptoms, as evidenced by the down-regulated airway resistance by 36%, 58% and 53% (p < 0.01, p < 0.001 vs. OVA/saline group), up-regulated lung compliance by 102%, 114% and 111%, decreased airway inflammation and mucus secretion by 33%, 40% and 33% (p < 0.001 vs. OVA/saline group). Moreover, the content of cytokines in BALF related to airway allergy (such as IgE) and T helper 1/T helper 2 cells (like IL-2, IL-4, IL-5, IL-13, TNF-α and IFN-γ), were also markedly reduced by 13-65% on LKZP intervention groups compared with model group. Mechanistic research revealed that the IL-33/ST2-NF-κB/GSK3ß/mTOR signalling pathway was activated in the OVA/saline group and LKZP significantly down-regulated this pathway. DISCUSSION AND CONCLUSION: LKZP improves lung function, airway inflammation, mucus secretion and correct immune imbalance by intervening with the IL-33/ST2-NF-κB/GSK3ß/mTOR signalling pathway, presenting a promising therapeutic choice for asthma.


Assuntos
Asma , NF-kappa B , Animais , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Glicogênio Sintase Quinase 3 beta/metabolismo , Inflamação/patologia , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Interleucina-33/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Ovalbumina , Serina-Treonina Quinases TOR/metabolismo
16.
Phytomedicine ; 105: 154345, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35905568

RESUMO

BACKGROUND: Asthma is a chronic airway disorder with a hallmark feature of airflow obstruction that associated with the remodeling and inflammation in the airway wall. Effective therapy for controlling both remodeling and inflammation is still urgently needed. Leonuride is the main pharmacological component identified from Bu-Shen-Yi-Qi-Tang (BSYQT) which has been traditionally used in treatment of lung diseases. However, no pharmacological effects of leonuride in asthma were reported. PURPOSE: Here we aimed to investigated whether leonuride provided a therapeutic efficacy in reversing asthma airway remodeling and inflammation and uncover the underlying mechanisms. STUDY DESIGN AND METHODS: Mouse models of chronic asthma were developed with ovalbumin (OVA) exposure for 8 weeks. Respiratory mechanics, lung histopathology and asthma-related cytokines were examined. Lung tissues were analyzed using RNA sequencing to reveal the transcriptional profiling changes. RESULTS: After oral administration with leonuride (15 mg/kg or 30 mg/kg), mice exhibited a lower airway hyperresponsiveness in comparison to asthmatic mice. Leonuride suppressed airway inflammation evidenced by the significant reductions in accumulation of inflammatory cells around bronchi and vessels, leukocyte population counts and the abundance of type 2 inflammatory mediators (OVA specific IgE, IL-4, IL-5 and IL-13) in bronchoalveolar lavage fluid (BALF). On the other hand, leonuride slowed down the process of active remodeling as demonstrated by weaker goblet cell metaplasia and subepithelial fibrosis in lung histopathology and lower transforming growth factor (TGF)-ß1 levels in serum and BALF in comparison to mice treated with OVA only. Furthermore, we uncovered transcriptional profiling alternations in lung tissue of mice after OVA exposure and leonuride treatment. Gene sets belonging to type-2 cytokine/chemokine activity stood out in leonuride target transcripts. Those upregulated (Bmp10, Ccl12, Ccl22, Ccl8, Ccl9, Cxcl15, Il13, Il33, Tnfrsf9, Il31ra, Il5ra, Il13ra2 and Ccl24) or downregulated (Acvr1c and Il18) genes in asthmatic mice, were all reversely regulated by leonuride treatment. CONCLUSIONS: Our results revealed the therapeutic efficacy of leonuride in experimental chronic asthma for the first time, and implied that its anti-inflammatory and antifibrotic properties might be mediated by regulation of type-2 high cytokine/chemokines responses.


Assuntos
Asma , Citocinas , Animais , Líquido da Lavagem Broncoalveolar , Quimiocinas , Modelos Animais de Doenças , Inflamação , Glicosídeos Iridoides , Iridoides , Pulmão , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Piranos
17.
Prog Lipid Res ; 87: 101178, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35780915

RESUMO

Fatty acid binding proteins (FABPs) are key proteins in lipid transport, and the isoforms are segregated according to their tissue origins. Several isoforms, such as adipose-FABP and epidermal-FABP, have been shown to participate in multiple pathologic processes due to their ubiquitous expression. Intestinal fatty acid binding protein, also termed FABP2 or I-FABP, is specifically expressed in the small intestine. FABP2 can traffic lipids from the intestinal lumen to enterocytes and bind superfluous fatty acids to maintain a steady pool of fatty acids in the epithelium. As a lipid chaperone, FABP2 can also carry lipophilic drugs to facilitate targeted transport. When the integrity of the intestinal epithelium is disrupted, FABP2 is released into the circulation. Thus, it can potentially serve as a clinical biomarker. In this review, we discuss the pivotal role of FABP2 in intestinal lipid metabolism. We also summarize the molecular interactions that have been reported to date, highlighting the clinical prospects of FABP2 research.


Assuntos
Proteínas de Ligação a Ácido Graxo , Metabolismo dos Lipídeos , Proteínas de Ligação a Ácido Graxo/metabolismo , Ácidos Graxos/metabolismo , Mucosa Intestinal/metabolismo , Intestinos
18.
J Mater Chem B ; 10(31): 5989-6000, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35876487

RESUMO

Material jetting bioprinting is a highly promising three-dimensional (3D) bioprinting technique that facilitates drop-on-demand (DOD) deposition of biomaterials and cells at pre-defined positions with high precision and resolution. A major challenge that hinders the prevalent use of the material jetting bioprinting technique is due to its limited range of printable hydrogel-based bio-inks. As a proof-of-concept, further modifications were made to gelatin methacrylate (GelMA), a gold-standard bio-ink, to improve its printability in a thermal inkjet bioprinter (HP Inc. D300e Digital Dispenser). A two-step modification process comprising saponification and heat treatment was performed; the GelMA bio-ink was first modified via a saponification process under highly alkali conditions to obtain saponified GelMA (SP-GelMA), followed by heat treatment via an autoclaving process to obtain heat-treated SP-GelMA (HSP-GelMA). The bio-ink modification process was optimized by evaluating the material properties of the GelMA bio-inks via rheological characterization, the bio-ink crosslinking test, nuclear magnetic resonance (NMR) spectroscopy and the material swelling ratio after different numbers of heat treatment cycles (0, 1, 2 and 3 cycles). Lastly, size-exclusion chromatography with multi-angle light scattering (SEC-MALS) was performed to determine the effect of heat treatment on the molecular weight of the bio-inks. In this work, the 4% H2SP-GelMA bio-inks (after 2 heat treatment cycles) demonstrated good printability and biocompatibility (in terms of cell viability and proliferation profile). Furthermore, thermal inkjet bioprinting of the modified hydrogel-based bio-ink (a two-step modification process comprising saponification and heat treatment) via direct/indirect cell patterning is a facile approach for potential fundamental cell-cell and cell-material interaction studies.


Assuntos
Bioimpressão , Bioimpressão/métodos , Gelatina/química , Temperatura Alta , Hidrogéis/química , Tinta , Metacrilatos/química , Impressão Tridimensional , Tecidos Suporte/química
19.
Sci Adv ; 8(29): eabm5752, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35857830

RESUMO

Inspired by the collective intelligence in natural swarms, microrobotic agents have been controlled to form artificial swarms for targeted drug delivery, enhanced imaging, and hyperthermia. Different from these well-investigated tasks, this work aims to develop microrobotic swarms for embolization, which is a clinical technique used to block blood vessels for treating tumors, fistulas, and arteriovenous malformations. Magnetic particle swarms were formed for selective embolization to address the low selectivity of the present embolization technique that is prone to cause complications such as stroke and blindness. We established an analytical model that describes the relationships between fluid viscosity, flow rate, branching angle, magnetic field strength, and swarm integrity, based on which an actuation strategy was developed to maintain the swarm integrity inside a targeted region under fluidic flow conditions. Experiments in microfluidic channels, ex vivo tissues, and in vivo porcine kidneys validated the efficacy of the proposed strategy for selective embolization.

20.
BMC Vet Res ; 18(1): 270, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35821025

RESUMO

BACKGROUND: Salmonella is a leading foodborne and zoonotic pathogen, and is widely distributed in different nodes of the pork supply chain. In recent years, the increasing prevalence of antimicrobial resistant Salmonella poses a threat to global public health. The purpose of this study is to the prevalence of antimicrobial resistant Salmonella in pig slaughterhouses in Hubei Province in China, and explore the effect of using lytic bacteriophages fighting against antimicrobial resistant Salmonella. RESULTS: We collected a total of 1289 samples including anal swabs of pigs (862/1289), environmental swabs (204/1289), carcass surface swabs (36/1289) and environmental agar plates (187/1289) from eleven slaughterhouses in seven cities in Hubei Province and recovered 106 Salmonella isolates. Antimicrobial susceptibility testing revealed that these isolates showed a high rate of antimicrobial resistance; over 99.06% (105/106) of them were multidrug resistant. To combat these drug resistant Salmonella, we isolated 37 lytic phages using 106 isolates as indicator bacteria. One of them, designated ph 2-2, which belonged to the Myoviridae family, displayed good capacity to kill Salmonella under different adverse conditions (exposure to different temperatures, pHs, UV, and/or 75% ethanol) and had a wide lytic spectrum. Evaluation in mouse models showed that ph 2-2 was safe and saved 80% (administrated by gavage) and 100% (administrated through intraperitoneal injection) mice from infections caused by Salmonella Typhimurium. CONCLUSIONS: The data presented herein demonstrated that Salmonella contamination remains a problem in some pig slaughter houses in China and Salmonella isolates recovered in slaughter houses displayed a high rate of antimicrobial resistance. In addition, broad-spectrum lytic bacteriophages may represent a good candidate for the development of anti-antimicrobial resistant Salmonella agents.


Assuntos
Myoviridae , Salmonelose Animal , Doenças dos Suínos , Matadouros , Animais , Modelos Animais de Doenças , Camundongos , Salmonelose Animal/terapia , Salmonella typhimurium/virologia , Suínos
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