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1.
Neural Regen Res ; 17(1): 210-216, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34100458

RESUMO

In Alzheimer's disease and ischemic stroke, intranasal insulin can act as a neuroprotective agent. However, whether intranasal insulin has a neuroprotective effect in intracerebral hemorrhage and its potential mechanisms remain poorly understood. In this study, a mouse model of autologous blood-induced intracerebral hemorrhage was treated with 0.5, 1, or 2 IU insulin via intranasal delivery, twice per day, until 24 or 72 hours after surgery. Compared with saline treatment, 1 IU intranasal insulin treatment significantly reduced hematoma volume and brain edema after cerebral hemorrhage, decreased blood-brain barrier permeability and neuronal degeneration damage, reduced neurobehavioral deficits, and improved the survival rate of mice. Expression levels of p-AKT and p-GSK3ß were significantly increased in the perihematoma tissues after intranasal insulin therapy. Our findings suggest that intranasal insulin therapy can protect the neurological function of mice after intracerebral hemorrhage through the AKT/GSK3ß signaling pathway. The study was approved by the Ethics Committee of the North Sichuan Medical College of China (approval No. NSMC(A)2019(01)) on January 7, 2019.

2.
Neural Regen Res ; 17(3): 682-689, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34380910

RESUMO

SNCA, GBA, and VPS35 are three common genes associated with Parkinson's disease. Previous studies have shown that these three genes may be associated with Alzheimer's disease (AD). However, it is unclear whether these genes increase the risk of AD in Chinese populations. In this study, we used a targeted gene sequencing panel to screen all the exon regions and the nearby sequences of GBA, SNCA, and VPS35 in a cohort including 721 AD patients and 365 healthy controls from China. The results revealed that neither common variants nor rare variants of these three genes were associated with AD in a Chinese population. These findings suggest that the mutations in GBA, SNCA, and VPS35 are not likely to play an important role in the genetic susceptibility to AD in Chinese populations. The study was approved by the Ethics Committee of Xiangya Hospital, Central South University, China on March 9, 2016 (approval No. 201603198).

3.
Front Cell Dev Biol ; 9: 703969, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631700

RESUMO

Ovarian cancer (OC) is the leading cause of cancer-related death among all gynecological tumors. N6-methyladenosine (m6A)-related regulators play essential roles in various tumors, including OC. However, the expression of m6A RNA methylation regulators and the related regulatory network in OC and their correlations with prognosis remain largely unknown. In the current study, we obtained the genome datasets of OC from GDC and GTEx database and analyzed the mRNA levels of 21 key m6A regulators in OC and normal human ovarian tissues. The expression levels of 7 m6A regulators were lower in both the OC tissues and the high-stage group. Notably, the 5-year survival rate of patients with OC presenting low VIRMA expression or high HNRNPA2B1 expression was higher than that of the controls. Next, a risk score model based on the three selected m6A regulators (VIRMA, IGF2BP1, and HNRNPA2B1) was built by performing a LASSO regression analysis, and the moderate accuracy of the risk score model to predict the prognosis of patients with OC was examined by performing ROC curve, nomogram, and univariate and multivariate Cox regression analyses. In addition, a regulatory network of miRNAs-m6A regulators-m6A target genes, including 2 miRNAs, 3 m6A regulators, and 47 mRNAs, was constructed, and one of the pathways, namely, miR-196b-5p-IGF2BP1-PTEN, was initially validated based on bioinformatic analysis and assay verification. These results demonstrated that the risk score model composed of three m6A RNA methylation regulators and the related network of miRNAs-m6A regulators-m6A target genes is valuable for predicting the prognosis of patients with OC, and these molecules may serve as potential biomarkers or therapeutic targets in the future.

4.
Front Physiol ; 12: 718827, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603078

RESUMO

Increased muscle stiffness can contribute to reduced range of motion (ROM) and impaired function. Reduced ankle dorsiflexion ROM has been associated with increased injury risk in the ankle. Self-myofascial release (SMR) has been widely used in clinical and sports settings, but the effects of SMR on gastrocnemius and Achilles tendon (AT) stiffness are unclear. Therefore, we investigated the effects of self-myofascial release using a foam roller (FR) on the stiffness of the gastrocnemius-AT complex and ankle dorsiflexion ROM. Fifty healthy, untrained, and non-sedentary participants (age=22.5±2.6years) were randomly divided into an intervention group (FR group) and a control group. The subjects in the intervention group received a single foam roller intervention (three sets of 1min), while the subjects in the control group performed a 5-min sedentary rest. Stiffness of the gastrocnemius-AT complex was evaluated using MyotonPRO and the ankle dorsiflexion ROM was assessed using the weight-bearing lunge test. For the foam roller and control groups, the between-group analysis revealed a statistically significant difference in gastrocnemius stiffness and ankle dorsiflexion ROM after intervention (p<0.05). Within-group analysis revealed a significant increase in ROM and a significant decrease in medial and lateral gastrocnemius (LG) stiffness for the foam roller group after the intervention (p<0.05). In addition, further analysis of the preintervention data revealed a significant negative correlation between ankle dorsiflexion ROM and AT stiffness (r=-0.378 and p=0.007). These results suggest that self-myofascial release using a foam roller on the calf is an effective method for decreasing the stiffness of the gastrocnemius and increasing ankle dorsiflexion ROM.

5.
Front Vet Sci ; 8: 719927, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660762

RESUMO

Inulin as a commercial prebiotic could selectively promote the growth of beneficial gut microbes such as lactic acid bacteria (LAB). Whether LAB in rabbit gut possesses the capability to metabolize and utilize inulin is little known. Therefore, this study recovered 94 LAB strains from neonate rabbits and found that only 29% (28/94) could metabolize inulin with both species- and strain-specificity. The most vigorous inulin-degrading strain, Lacticaseibacillus paracasei YT170, could efficiently utilize both short-chain and long-chain components through thin-layer chromatography analysis. From genomic analysis, a predicted fosRABCDXE operon encoding putative cell wall-anchored fructan ß-fructosidase, five fructose-transporting proteins and a pts1BCA operon encoding putative ß-fructofuranosidase and sucrose-specific IIBCA components were linked to long-chain and short-chain inulin utilization respectively. This study provides a mechanistic rationale for effect of inulin administration on rabbits and lays a foundation for synbiotic applications aimed at modulating the intestinal microbiota of young rabbits.

6.
Metab Eng ; 68: 142-151, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34610458

RESUMO

Glycolysis is the primary metabolic pathway in all living organisms. Maintaining the balance of glycolysis flux and biosynthetic pathways is the crucial matter involved in the microbial cell factory. Few regulation systems can address the issue of metabolic flux imbalance in glycolysis. Here, we designed and constructed a bifunctional glycolysis flux biosensor that can dynamically regulate glycolysis flux for overproduction of desired biochemicals. A series of positive-and negative-response biosensors were created and modified for varied thresholds and dynamic ranges. These engineered glycolysis flux biosensors were verified to be able to characterize in vivo fructose-1,6-diphosphate concentration. Subsequently, the biosensors were applied for fine-tuning glycolysis flux to effectively balance the biosynthesis of two chemicals: mevalonate and N-acetylglucosamine. A glycolysis flux-dynamically controlled Escherichia coli strain achieved a 111.3 g/L mevalonate titer in a 1L fermenter.

7.
Adv Mater ; : e2106184, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34647640

RESUMO

Stretchable electroluminescent (EL) devices have been obtained by partitioning a large emission area into areas specifically for stretching and light-emission (island-bridge structure). Buckled and textile structures have also been shown effective to combine the conventional light emitting diode fabrication with elastic substrates for structure-enabled stretchable EL devices. Meanwhile, intrinsically stretchable EL devices which are characterized with uniform stretchability down to microscopic scale are relatively less developed but promise simpler device structure and higher impact resistance. The challenges in fabricating intrinsically stretchable EL devices with high and robust performance are in many facets, including stretchable conductors, emissive materials, and compatible processes. For the stretchable transparent electrode, ionically conductive gel, conductive polymer coating, and conductor network in surface of elastomer have all been proven useful. The stretchable EL materials are currently limited to conjugated polymers, conjugated polymers with surfactants and ionic conductors added to boost stretchability, and phosphor particles embedded in elastomer matrices. These emissive materials operate under different mechanisms, require different electrode materials and fabrication processes, and the corresponding EL devices face distinctive challenges. This review aims to provide a basic understanding of the materials meeting both the mechanical and electronic requirements and important techniques to fabricate the stretchable EL devices. This article is protected by copyright. All rights reserved.

8.
J Control Release ; 339: 506-520, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34655677

RESUMO

The combination of nitric oxide (NO) and siRNA is highly desirable for cancer therapy. Here, the furoxans-grafted PEI polymer (FDP) with caspase-3 responsive cleavable DEVD linker was synthesized, and used to bind siRNAs via electrostatic interaction and self-assembled into FDP/siRNA nanoplexes by hydrophobic force. After cellular uptake and lysosomal escape, the FDP/siRNA nanoplexes could achieve GSH-triggered NO release, and then increase the activity of caspase-3. The activated caspase-3 could specifically cleave the DEVD peptide sequence and enhance cell apoptosis. With the cleavage of DEVD peptide sequence, the disassembly of FDP/siRNA nanoplexes was further promoted, thereby resulting in increased siRNAs of ~40% were released at 48 h compared with the caspase-3 non-responsive FDnP/siRNA nanoplexes. By this way, cell apoptosis promotion and cell proliferation inhibition was achieved by siRNA-based downregulation of EGFR protein and the upregulated activity of caspase-3, followed by the enhanced cascade release of NO from FDP/siRNA nanoplexes. Furthermore, in vivo results demonstrated the improved anti-cancer efficiency of FDP/siEGFR nanoplexes without any detectable side effects. Therefore, it is believed that the caspase-3 responsive cleavable furoxans-grafted PEI polymers could provide a potential and efficient enhancement for cancer therapeutic efficiency by the co-delivery of nitric oxide and siRNA.

9.
PLoS Pathog ; 17(9): e1009918, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34529741

RESUMO

Under RNA virus infection, retinoic acid-inducible gene I (RIG-I) in host cells recognizes viral RNA and activates the expression of type I IFN. To investigate the roles of protein methyltransferases and demethylases in RIG-I antiviral signaling pathway, we screened all the known related enzymes with a siRNA library and identified LSD1 as a positive regulator for RIG-I signaling. Exogenous expression of LSD1 enhances RIG-I signaling activated by virus stimulation, whereas its deficiency restricts it. LSD1 interacts with RIG-I, promotes its K63-linked polyubiquitination and interaction with VISA/MAVS. Interestingly, LSD1 exerts its function in antiviral response not dependent on its demethylase activity but through enhancing the interaction between RIG-I with E3 ligases, especially TRIM25. Furthermore, we provide in vivo evidence that LSD1 increases antiviral gene expression and inhibits viral replication. Taken together, our findings demonstrate that LSD1 is a positive regulator of signaling pathway triggered by RNA-virus through mediating RIG-I polyubiquitination.

10.
Environ Pollut ; 291: 118094, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517175

RESUMO

Indoor air quality ((IAQ) in classrooms was associated with the daily exposure of school-age children who are particularly vulnerable to air pollutants exposure, while few data exist to evaluate classroom indoor air quality nationwide in China. The subsample of the CIEHS 2018 study was performed in 66 classrooms of 22 primary schools nationwide in China. Temperature, relative humidity, PM2.5, PM10, CO2, CO, formaldehyde concentrations, bacteria and fungi were detected in all classrooms by using the instruments that meet the specified accuracy. The ratios of indoor to outdoor (I/O) of PM2.5 were calculated in each classroom to identify whether the indoor environment the pollutants comes from outdoors. The indoor PM2.5, PM10, CO, HCHO, bacteria and fungi GM concentration are 47.40 µg/m3, 72.91 µg/m3, 0.37 mg/m3, 0.02 mg/m3, 347.51 CFU/m3 and 362.76 CFU/m3, respectively. We observed that there were 66.5%, 52.6%, 22.4%, 1.8%, and 9.6% of the classrooms that exceeded the guideline values of PM2.5, PM10, CO2, HCHO, and bacteria, respectively. It should be attention that all of the classroom's PM2.5 concentrations in Shijiazhuang and Nanning, PM10 concentrations in Nanning, CO2 concentration in Lanzhou were exceeded the suggested values. Bacteria contamination in Shijiazhuang's classrooms is also serious. All classroom CO concentrations meet the requirement. The results indicated that classroom indoor PM2.5 was significantly positively correlated with indoor PM10 and CO2, while was negative correlated with temperature, CO, and fungi. Our results suggest that indoor air pollution in classrooms was a severe problem in Chinese primary schools. It is necessary to strengthen ventilation in the classroom to improve indoor air quality. What's more, a healthy learning environment should be created for primary school students.

11.
Brain Behav Immun Health ; 17: 100342, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34589822

RESUMO

As they age, people living with HIV (PLWH) experience greater rates of inflammation-related health conditions compared to their HIV-negative peers. Because early life adversity can exaggerate proinflammatory effects of later physiological challenges, inflammation may be higher among PLWH with these combined risks, which could inform intervention approaches to mitigate multimorbidity. In this cross-sectional analysis, we investigated individual and combined effects of childhood sexual abuse (CSA) history and physiological burden (Veterans Aging Cohort Study Index scores) on serum cytokine and C-reactive protein (CRP) levels among PLWH. Participants (n â€‹= â€‹131; age 54 and older) were patients at an outpatient HIV clinic who completed a psychosocial survey and biomedical research visit as part of a larger study. 93% were virally suppressed, and 40% reported experiencing sexual abuse in childhood. Composite cytokine levels (summarizing IL-6, TNF-α, IFN-γ), CRP, and disease burden did not differ significantly between those who had a history of CSA and those who did not. Participants with greater disease burden had higher composite cytokine levels (r â€‹= â€‹0.29, p â€‹= â€‹0.001). The disease burden by CSA interaction effect was a significant predictor of composite cytokine levels (but not CRP), and remained significant after controlling for age, sex, race, BMI, anti-inflammatory medication use, selective serotonin reuptake inhibitor use, depressive symptoms, and smoking status (F(1, 114) â€‹= â€‹5.68, p â€‹= â€‹0.02). In follow-up simple slopes analysis, greater disease burden was associated with higher cytokine levels among those with CSA history (b â€‹= â€‹0.03, SE â€‹= â€‹0.008, p<0.001), but not among those without CSA history. Further, in the context of greater disease burden, individuals with a CSA history tended to have higher cytokine levels than those without a CSA history (b â€‹= â€‹0.38, SE â€‹= â€‹0.21, p â€‹= â€‹0.07). These data suggest that the physiological sequelae of childhood trauma may persist into older age among those with HIV. Specifically, links between physiological burden and inflammation were stronger among survivors of CSA in this study. The combined presence of CSA history and higher disease burden may signal a greater need for and potential benefit from interventions to reduce inflammation, an area for future work.

12.
Mater Sci Eng C Mater Biol Appl ; 128: 112326, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474877

RESUMO

Bone defects remain a challenging problem for doctors and patients in clinical practice. Processed pyritum is a traditional Chinese medicine that is often used to clinically treat bone fractures. It contains mainly Fe, Zn, Cu, Mn, and other elements. In this study, we added the extract of processed pyritum to ß-tricalcium phosphate and produced a porous composite TPP (TCP/processed pyritum) scaffold using digital light processing (DLP) 3D printing technology. Scanning electron microscopy (SEM) analysis revealed that TPP scaffolds contained interconnected pore structures. When compared with TCP scaffolds (1.35 ± 0.15 MPa), TPP scaffolds (5.50 ± 0.24 MPa) have stronger mechanical strength and can effectively induce osteoblast proliferation, differentiation, and mineralization in vitro. Meanwhile, the in vivo study showed that the TPP scaffold had better osteogenic capacity than the TCP scaffold. Furthermore, the TPP scaffold had good biosafety after implantation. In summary, the TPP scaffold is a promising biomaterial for the clinical treatment of bone defects.


Assuntos
Fosfatos de Cálcio , Tecidos Suporte , Humanos , Porosidade , Impressão Tridimensional
13.
Artigo em Inglês | MEDLINE | ID: mdl-34505945

RESUMO

PURPOSE: Obtaining tumour-free margins is critical for avoiding re-excision and reducing local recurrence following breast-conserving surgery; however, it remains challenging. Imaging-guided surgery provides precise detection of residual lesions and assists surgical resection. Herein, we described water-soluble melanin nanoparticles (MNPs) conjugated with cyclic Arg-Gly-Asp (cRGD) peptides for breast cancer photoacoustic imaging (PAI) and surgical navigation. METHODS: The cRGD-MNPs were synthesised and characterized for morphology, photoacoustic characteristics and stability. Tumour targeting and toxicity of cRGD-MNPs were determined by using either breast cancer cells, MDA-MB-231 tumour-bearing mice or the FVB/N-Tg (MMTV-PyVT) 634Mul/J mice model. PAI was used to locate the tumour and guide surgical resection in MDA-MB-231 tumour-bearing mice. RESULTS: The cRGD-MNPs exhibited excellent in vitro and in vivo tumour targeting with low toxicity. Intravenous administration of cRGD-MNPs to MDA-MB-231 tumour-bearing mice showed an approximately 2.1-fold enhancement in photoacoustic (PA) intensity at 2 h, and the ratio of the PA intensity at the tumour site to that in the surrounding normal tissue was 3.2 ± 0.1, which was higher than that using MNPs (1.7 ± 0.3). Similarly, the PA signal in the spontaneous breast cancer increased ~ 2.5-fold at 2 h post-injection of cRGD-MNPs in MMTV-PyVT transgenic mice. Preoperative PAI assessed tumour volume and offered three-dimensional (3D) reconstruction images for accurate surgical planning. Surgical resection following real-time PAI showed high consistency with histopathological analysis. CONCLUSION: These results highlight that cRGD-MNP-mediated PAI provide a powerful tool for breast cancer imaging and precise tumour resection. cRGD-MNPs with fine PA properties have great potential for clinical translation.

14.
Ann Palliat Med ; 10(8): 8909-8918, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34488378

RESUMO

BACKGROUND: The sinus tarsi syndrome (STS) is a common foot and ankle disease with controversial pathogenesis and treatment procedures. This long-term study aimed to analyze the effect of a staged surgical strategy for STS. METHODS: Clinical data were retrospectively analyzed in 273 STS patients [129 men and 144 women; mean age: 36 years (10-60 years)] treated between 2006 and 2016. The 89 patients underwent different surgeries, including sinus tarsal debridement, subtalar joint stabilization, sinus tarsal denervation, tarsal coalition resection, or subtalar arthrodesis. The patients' American Orthopedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores, visual analogue scale (VAS) scores for pain during daily activities, and 36-item short-form health survey (SF-36) scores at the first visit and latest follow-up were assessed by paired T-test. RESULTS: The 89 patients who failed conservative treatments first underwent tarsal sinus soft tissue debridement, with 52 patients remaining in remission after 2 years. The other 37 patients with relapse underwent further surgeries. Five of the 19 patients with subtalar instability were cured following ligament reconstruction surgery. Two of the four patients with severe neurological signs recovered after nerve release surgery. Five of the 10 patients with tarsal coalition were cured by resection of the talocalcaneal bridge. A total of 21 patients failed their second operations due to peroneal spasm, and were eventually successfully treated by subtalar arthrodesis. In addition, subtalar arthrodesis was directly performed in the remaining four patients with peroneal spastic flatfoot. After the final operations, all patients achieved satisfactory results. The AOFAS ankle-hindfoot scores increased from 34.83±12.21 preoperatively to 85.52±7.07 postoperatively (t=-24.62, P<0.01), the VAS scores decreased from 8.14±1.52 to 2.14±1.00 (t=24.65, P<0.01), and the SF-36 scores increased from 36.58±11.36 to 86.22±9.17 (t=-28.13, P<0.01). CONCLUSIONS: In this study, we observed that 67% (184/273) of patients with STS need a staged surgical management. According to the etiology, symptoms, and severity, soft tissue surgery is the first choice. However, simple soft tissue surgeries may fail to achieve long-term results. Once the symptoms recur and become difficult to cure, the staged surgical strategy for STS we proposed can be the best choice to achieve long-term results.


Assuntos
Doenças do Pé , Articulação Talocalcânea , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Articulação Talocalcânea/cirurgia , Resultado do Tratamento
15.
Brief Bioinform ; 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34571530

RESUMO

The identification of differentially expressed genes between different cell groups is a crucial step in analyzing single-cell RNA-sequencing (scRNA-seq) data. Even though various differential expression analysis methods for scRNA-seq data have been proposed based on different model assumptions and strategies recently, the differentially expressed genes identified by them are quite different from each other, and the performances of them depend on the underlying data structures. In this paper, we propose a new ensemble learning-based differential expression analysis method, scDEA, to produce a more stable and accurate result. scDEA integrates the P-values obtained from 12 individual differential expression analysis methods for each gene using a P-value combination method. Comprehensive experiments show that scDEA outperforms the state-of-the-art individual methods with different experimental settings and evaluation metrics. We expect that scDEA will serve a wide range of users, including biologists, bioinformaticians and data scientists, who need to detect differentially expressed genes in scRNA-seq data.

16.
CNS Neurosci Ther ; 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551193

RESUMO

AIM: The role of vascular dementia (VaD)-associated genes in Alzheimer's disease (AD) remains elusive despite similar clinical and pathological features. We aimed to explore the relationship between these genes and AD in the Chinese population. METHODS: Eight VaD-associated genes were screened by a targeted sequencing panel in a sample of 3604 individuals comprising 1192 AD patients and 2412 cognitively normal controls. Variants were categorized into common variants and rare variants according to minor allele frequency (MAF). Common variant (MAF ≥ 0.01)-based association analysis was conducted by PLINK 1.9. Rare variant (MAF < 0.01) association study and gene-based aggregation testing of rare variants were performed by PLINK 1.9 and Sequence Kernel Association Test-Optimal (SKAT-O test), respectively. Age at onset (AAO) and Mini-Mental State Examination (MMSE) association studies were performed with PLINK 1.9. Analyses were adjusted for age, gender, and APOE ε4 status. RESULTS: Four common COL4A1 variants, including rs874203, rs874204, rs16975492, and rs1373744, exhibited suggestive associations with AD. Five rare variants, NOTCH3 rs201436750, COL4A1 rs747972545, COL4A1 rs201481886, CST3 rs765692764, and CST3 rs140837441, showed nominal association with AD risk. Gene-based aggregation testing revealed that HTRA1 was nominally associated with AD. In the AAO and MMSE association studies, variants in GSN, ITM2B, and COL4A1 reached suggestive significance. CONCLUSION: Common variants in COL4A1 and rare variants in HTRA1, NOTCH3, COL4A1, and CST3 may be implicated in AD pathogenesis. Besides, GSN, ITM2B, and COL4A1 are probably involved in the development of AD endophenotypes.

17.
Biotechnol Prog ; : e3211, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34549552

RESUMO

Chinese hamster ovary (CHO) cells are by far the most important mammalian cell lines used for producing antibodies and other therapeutic proteins. It is critical to fully understand their physiological conditions during a bioprocess in order to achieve the highest productivity and the desired product quality. Flow cytometry technology possesses unique advantages for measuring multiple cellular attributes for a given cell and examining changes in cell culture heterogeneity over time that can be used as metrics for enhanced process understanding and control strategy. Flow cytometry-based assays were utilized to examine the progression of cell cycle and apoptosis in three case studies using different antibody-producing CHO cell lines in both fed-batch and perfusion bioprocesses. In our case studies, we found that G0/G1 phase distribution and early apoptosis accumulation responded to subtle changes in culture conditions, such as pH shifting or momentary glucose depletion. In a perfusion process, flow cytometry provided an insightful understanding of the cell physiological status under a hypothermic condition. More importantly, these changes in cell cycle and apoptosis were not detected by a routine trypan blue exclusion-based cell counting and viability measurement. In summary, integration of flow cytometry into bioprocesses as a process analytical technology tool can be beneficial for establishing optimum process conditions and process control.

18.
J Magn Reson Imaging ; 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34545977

RESUMO

BACKGROUND: Partial bile duct ligation (PBDL) model is a reliable cholestatic fibrosis experimental model that showed complex histopathological changes. Magnetic resonance imaging (MRI) features of PBDL have not been well characterized. PURPOSE: To investigate the potential of MRI parameters in assessing fibrosis in PBDL and explore the relationships between MRI and pathological features. ANIMAL MODEL: Established PBDL models. POPULATION: Fifty-four mice were randomly divided into four timepoints PBDL groups and one sham group. FIELD STRENGTH/SEQUENCE: 3.0 T; MRI sequences included T1-weighted fast spin-echo (FSE), T2-weighted single shot FSE, variable flip angle T1 mapping, multi-echo SE T2 mapping, multi-echo gradient-echo T2* mapping, and multi-b-value diffusion-weighted imaging. ASSESSMENT: MRI examination was performed at the corresponding timepoints after surgery. Native T1, ΔT1 (T1native-T1post), T2, T2*, apparent diffusion coefficient (ADC) values, histogram parameters (skewness and kurtosis), intravoxel incoherent motion parameters (f, D, and D* ) within the entire ligated (PBDL), non-ligated liver (PBDL), and whole liver (sham) were obtained. Fibrosis and inflammation were assessed in Masson and H&E staining slices using the Metavir and activity scoring system. STATISTICAL TESTS: One-way ANOVA, Spearman's rank correlation, and receiver operating characteristic curves were performed. P < 0.05 was considered statistically significant. RESULTS: Fibrosis and inflammation were finally staged as F3 and A3 in ligated livers but were not observed in non-ligated or sham livers. Ligated livers displayed significantly elevated native T1, ΔT1, T2, and reduced ADC and T2* than other livers. Spearman's correlation showed better correlation with inflammation (r = 0.809) than fibrosis (r = 0.635) in T2 and both ΔT1 and ADC showed stronger correlation with fibrosis (r = 0.704 and r = -0.718) than inflammation (r = 0.564 and r = -0.550). Area under the curve (AUC) for ΔT1 performed the highest (0.896). When combined with all relative parameters, AUC increased to 0.956. DATA CONCLUSION: Multiparametric MRI can evaluate and differentiate pathological changes in PBDL. ΔT1 and ADC better correlated with fibrosis while T2 stronger with inflammation. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.

19.
Histol Histopathol ; : 18370, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34472621

RESUMO

The increasing demand for bone grafts and the scarcity of donors worldwide are promoting researchers to seek alternatives. The extracellular matrix (ECM) has been reported to enhance properties of osteoconduction and osteoinduction by simulating the molecular structure of bone and facilitating cell infiltration for bone repair. As one of several novel biomaterials, ECM has many desirable properties, including biocompatibility, bioactivity, and biosafety. Thus, we evaluated whether ECM is a promising scaffold biomaterial for bone repair. In this review, we explore ECM composition, the sources and fabrication methods, especially the decellularization technique, of ECM scaffolds. Furthermore, we highlight recent progress in the use of ECM as a scaffold biomaterial for bone repair. Generally, ECM is used in 1) three-dimensional (3D) cell cultures to promote osteogenic differentiation, 2) combinations with other biomaterials to increase their osteogenic effects, 3) 3D printing to produce customized or patient-tailored scaffolds for bone repair, and 4) hydrogels derived from ECM used for bone repair. In addition, we focus on future prospects for application of ECM as a scaffold material used for bone repair. From this review, we expect to have a perfect understanding of ECM-based scaffold materials in the hope that this leads to further research of the production of ECM biomaterials to meet the clinical needs for bone repair.

20.
J Environ Manage ; 298: 113377, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34375917

RESUMO

This study aimed to explore whether the "window" effect of static magnetic field (SMF) on nitrous oxide (N2O) emission from the biological nitrogen removal process at low temperature existed and reveal its biological mechanism at the gene level. Four sequencing batch reactors (SBRs) with SMFs of 0, 10, 45, and 75 mT were operated continuously for 110 days at 10 °C and the lowest N2O-Gas cumulative emission (5.50 mg N/day) and N2O conversion rate (4.28 %) in 45 mT SMF-SBR verified the existence of the "window" effect. In 45 mT SMF-SBR, nearly all enzymatic activities related to N2O reduction and corresponding functional gene abundances improved significantly. Metagenomic high-throughput sequencing analysis revealed that Alicycliphilus denitricans, Paracoccus denitrificans, Rhodopseudomonas palustris, Pseudomonas stutzeri, and Dechloromonas aromatica, as species related to N2O reduction, could be separately enriched by applying suitable SMF intensity. Gene functions annotation based on KEGG and CAZy databases indicated that SMF not only accelerated the rate of free ammonia into ammonia-oxidizing bacteria and electrons delivered to the corresponding denitrification reductases, but also enhanced the degradation of complex organic matter into smaller molecules, and thus reducing the production of N2O via nitrifier denitrification and incomplete denitrification pathways at 10 °C. These findings provided a guideline and presented a blueprint of ecophysiology for the future application of magnetic field to the reduction of N2O emission in wastewater treatment plants in the cold region.


Assuntos
Desnitrificação , Óxido Nitroso , Betaproteobacteria , Reatores Biológicos , Campos Magnéticos , Nitrificação , Nitrogênio , Óxido Nitroso/análise , Rodopseudomonas , Esgotos , Temperatura
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