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1.
Front Microbiol ; 15: 1352430, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38618484

RESUMEN

In view of water and soil getting polluted by Pb(II), Zn(II), and other heavy metals in tailings and acid mine drainage (AMD), we explored the removal effect of sulfate-reducing bacteria (SRB) on Pb(II), Zn(II), and other pollutants in solution and tailings based on the microbial treatment technology. We used the scanning electron microscope-energy dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD), and X-ray fluorescence (XRF), to reveal the mechanism of SRB treatment of tailings. The results showed that SRB had a strong removal capacity for Zn(II) at 0-40 mg/L; however, Zn(II) at 60-100 mg/L inhibited the growth of SRB. Similarly, SRB exhibited a very strong ability to remove Pb(II) from the solution. At a Pb(II) concentration of 10-50 mg/L, its removal percentage by SRB was 100%. SRB treatment could effectively immobilize the pollutants leached from the tailings. With an increase in the amount of tailings added to each layer, the ability of SRB to treat the pollutants diminished. When 1 cm of tailingssand was added to each layer, SRB had the best effect on tailing sand treatment. After treatment, the immobilization rates of SO42-, Fe(III), Mn(II), Pb(II), Zn(II), Cu(II), and total Cr in the leachate of #1 tailing sand were 95.44%, 100%, 90.88%, 100%, 96.20%, 86.23%, and 93.34%, respectively. After the tailings were treated by SRB, although the tailings solidified into a cohesive mass from loose granular particles, their mechanical strength was <0.2 MPa. Desulfovibrio and Desulfohalotomaculum played the predominant roles in treating tailings by mixing SRB. The S2- and carbonate produced by mixing SRB during the treatment of tailings could metabolize sulfate by combining with the heavy metal ions released by the tailings to form FeS, MnS, ZnS, CuS, PbS, Cr2S3, CaCO3, MnCO3, and other precipitated particles. These particles were attached to the surface of the tailings, reducing the environmental pollution of the tailings in the water and soil around the mining area.

2.
Water Res ; 255: 121493, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38547788

RESUMEN

Total phosphorus (TP) is non-optically active, thus TP concentration (CTP) estimation using remote sensing still exists grand challenge. This study developed a deep neural network model (DNN) for CTP estimation with synchronous in-situ measurements and MODIS-derived remote sensing reflectance (Rrs) (N = 3916). Using DNN, the annual and intra-annual CTP spatial distributions of the Great Lakes since 2002 were reconstructed. Then, the reconstructions were correlated to nine potential factors, e.g., Chlorophyll-a, snowmelt, and cropland, to explain seasonal and long-term CTP variations. The results showed that DNN reliably estimated CTP from MODIS Rrs, with R2, mean absolute error (MAE), root mean squared error (RMSE), mean absolute percentage error (MAPE), and root mean squared logarithmic error (RMSLE) of 0.83, 1.05 µg/L, 2.95 µg/L, 9.92%, and 0.13 on the test set. The near-surface CTP in the Great Lakes decreased significantly (p < 0.05) during 2002 - 2022, primarily attributed to cropland reduction, coupled with improvements in basin natural ecosystems. The sensitivity analysis verified the model robustness when confronted with input feature changes < 35%. This result along with the marginal difference between CTP derived from two sensors (R2 = 0.76, MAE = 2.12 µg/L, RMSE = 2.51 µg/L, MAPE = 11.52%, RMSLE = 0.24) suggested the model transferability from MODIS to VIIRS. This transformation facilitated optimal usage of MODIS-related archive and enhanced the continuity of CTP estimation at moderate resolution. This study presents a practical method for spatiotemporal reconstruction of CTP using remote sensing, and contributes to better understandings of driving factors behind CTP variations in the Great Lakes.

3.
Mol Neurobiol ; 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38401045

RESUMEN

As a famous prescription in China, AnGong NiuHuang (AGNH) pill exerts good neuroprotection for ischaemic stroke (IS), but its mechanism is still unclear. In this study, the neuroprotection of AGNH was evaluated in the rat IS model which were established with the surgery of middle cerebral artery occlusion (MCAO), and the potential mechanism was elucidated by transcriptomic analysis and metabolomic analysis. AGNH treatment obviously decreased the infarct volume and Zea-Longa 5-point neurological deficit scores, improved the survival percentage of rats, regional cerebral blood flow (rCBF), and rat activity distance and activity time. Transcriptomics showed that AGNH exerted its anti-inflammatory effects by affecting the regulatory network including Tyrobp, Syk, Tlr2, Myd88 and Ccl2 as the core. Integrating transcriptomics and metabolomics identified 8 key metabolites regulated by AGNH, including L-histidine, L-serine, L-alanine, fumaric acid, malic acid, and N-(L-arginino) succinate, 1-pyrroline-4-hydroxy-2-carboxylate and 1-methylhistamine in the rats with IS. Additionally, AGNH obviously reduced Tyrobp, Syk, Tlr2, Myd88 and Ccl2 at both the mRNA and protein levels, decreased IL-1ß, KC-GRO, IL-13, TNF-α, cleaved caspase 3 and p65 nucleus translocation, but increased IκBα expression. Network pharmacology analysis showed that quercetin, beta-sitosterol, baicalein, naringenin, acacetin, berberine and palmatine may play an important role in protecting against IS. Taken together, this study reveals that AGNH reduced neuroinflammation and protected against IS by inhibiting Tyrobp/Syk and Tlr2/Myd88, as well as NF-κB signalling pathway and regulating multiple metabolites.

4.
Cell Biochem Funct ; 42(2): e3937, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38329451

RESUMEN

The antiobesity effect of conjugated linoleic acid (CLA) has been reported. However, the underlying mechanisms have not been fully clarified. Thus, this study aimed to investigate the effects of CLA on thermogenesis of interscapular brown adipose tissue (iBAT) and browning of inguinal subcutaneous white adipose tissue (iWAT) and explore the possible signaling pathway. The in vivo results showed that CLA enhanced the O2 consumption and heat production in HFD (high-fat diet)-fed female mice by roughly 38%. Meanwhile, CLA increased the average iBAT temperature by 2°C at the room temperature and cold exposure, respectively. Correspondingly, CLA caused 1.6- and 2.4-fold increases in the expression of UCP1 (uncoupling protein 1) of BAT and iWAT, respectively, suggesting the activated iBAT thermogenesis and iWAT browning in HFD-fed female mice. Meanwhile, CLA could promote the formation of brown and beige adipocytes in differentiated stromal vascular cells (SVCs) isolated from iBAT and iWAT (the expressions of UCP1 were promoted by about twofold changes). In possible mechanisms, CLA stimulated the expression of CD36 and the activation of the AMPK pathway in mice iBAT and iWAT as well as the differentiated SVCs. However, inhibition of CD36 and AMPK (adenosine 5'-monophosphate-activated protein kinase) abolished the promotive effects of CLA on brown and beige adipocytes formation. Hence, we showed that CLA reduced HFD-induced obesity through enhancing iBAT thermogenesis and iWAT browning via the  CD36-AMPK pathway.


Asunto(s)
Adipocitos Beige , Ácidos Linoleicos Conjugados , Femenino , Animales , Ratones , Ácidos Linoleicos Conjugados/farmacología , Proteínas Quinasas Activadas por AMP , Obesidad/tratamiento farmacológico , Termogénesis
5.
Int J Rheum Dis ; 27(1): e15020, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38287552

RESUMEN

AIM: IL-38 is a recently discovered inflammatory factor that belongs to the IL-1 family and has full-length and truncated forms. Clinical findings demonstrated that serum IL-38 levels in people with infectious and autoimmune diseases are significantly different from those in healthy people, but the form remains unclear. We are keenly interested in learning more about the regulatory role of full-length IL-38 in rheumatoid arthritis (RA), a classic autoimmune disease. METHODS: RA-fibroblast-like synoviocytes (RA-FLS) were isolated from six RA patients and stimulated with full-length IL-38 to observe IL-6 and IL-8 secretion. Then, the migration and invasion functions of FLS were assessed. Next, the protein expressions of the MAPK, NF-κB, and JAK pathways were evaluated. In addition, we examined the effect of full-length IL-38 on FLS functions in the presence of IL-1ß. The function of FLS affected by full-length IL-38 was also examined after blocking IL-1 and IL-36 receptors. RESULTS: The functions of FLS were activated after the cells were stimulated with full-length IL-38. IL-6 and IL-8 levels increased with an increase in the full-length IL-38 concentration, and full-length IL-38 induced the acceleration of FLS migration and invasion functions. In addition, the levels of proteins in the MAPK signaling pathway increased after stimulation with full-length IL-38 and depended on its concentration. However, when the FLS were stimulated by IL-38 and IL-1ß simultaneously, all experiments generated opposite results. Full-length IL-38 inhibited FLS function in the presence of IL-1ß. IL-1R and IL-36R blockers terminated all effects of full-length IL-38 on RA-FLS. CONCLUSION: Full-length IL-38 activates FLS functions and acts as a promoter in RA, whereas it inhibits FLS functions and acts as an inhibitor of RA in the presence of IL-1ß. The function of full-length IL-38 can be blocked by IL-1Ra and IL-36Ra.


Asunto(s)
Artritis Reumatoide , Sinoviocitos , Humanos , Sinoviocitos/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Células Cultivadas , Artritis Reumatoide/genética , Artritis Reumatoide/metabolismo , Fibroblastos/metabolismo , Interleucina-1 , Membrana Sinovial , Interleucinas/farmacología
6.
Int J Parasitol ; 54(2): 99-107, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37774810

RESUMEN

The successful completion of gamete fertilization is essential for malaria parasite transmission, and this process can be targeted by intervention strategies. In this study, we identified a conserved gene (PBANKA_0813300) in the rodent malaria parasite Plasmodium berghei, which encodes a protein of 54 kDa (designated as Pbs54). Localization studies indicated that Pbs54 is associated with the plasma membranes of gametes and ookinetes. Functional studies by gene disruption showed that the Δpbs54 parasites had no defect in asexual proliferation, gametocyte development, or gametogenesis. However, the interactions between male and female gametes were significantly decreased compared with wild-type parasites. The Δpbs54 lines did not show a further reduction in zygote and ookinete numbers during in vitro culture, indicating that the defects were probably restricted to gamete fertilization. Consistent with this finding, mosquitoes fed on Δpbs54-infected mice showed a 30.1% reduction in infection prevalence and a 74.7% reduction in oocyst intensity. Cross-fertilization assay indicated that both male and female gametes were impaired in the Δpbs54 parasites. To evaluate its transmission-blocking potential, we obtained polyclonal antibodies from mice immunized with the recombinant Pbs54 (rPbs54) protein. In vitro assays showed that anti-rPbs54 sera inhibited ookinete formation by 42.7%. Our experiments identified Pbs54 as a fertility factor required for mosquito transmission and a novel candidate for a malaria transmission-blocking vaccine.


Asunto(s)
Culicidae , Vacunas contra la Malaria , Malaria , Animales , Femenino , Masculino , Ratones , Anticuerpos Antiprotozoarios , Fertilización , Células Germinativas , Malaria/prevención & control , Proteínas de la Membrana/genética , Plasmodium berghei/genética , Plasmodium berghei/metabolismo , Proteínas Protozoarias/metabolismo , Proteínas Recombinantes
7.
Front Psychiatry ; 14: 1236636, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38076701

RESUMEN

Background: Adults with attention-deficit/hyperactivity disorder (ADHD) may experience sleep problems doubly suffering from the disease and side effects of stimulant medications. Physical activity (PA) is known to produce numerous beneficial effects in adults. However, it was not well-characterized whether PA would still be effective in this situation. The main objective of the current study was to examine the relationship between PA and sleep among adult ADHD patients who were using stimulant medications and quantify the form of this association. Methods: Adult ADHD participants with stimulant medications use condition from the National Health and Nutrition Examination Survey (NHANES) database between January 1, 2013, and March 2020 (prepandemic) were included in the cross-sectional analysis. Weighted logistic regression was performed to assess the relationship between PA level and sleep. A restricted cubic spline model was used to relax the linear relationship assumptions and investigate the associations between the risk of trouble sleeping and time spent engaging in moderate-to-vigorous PA per week. Results: A total of 162 eligible adult ADHD participants who reported using stimulant medicines were included. Participants who adhered to the general recommendation of guidelines in the US of 150 min per week of moderate-to-vigorous PA had a significant lower risk of complaining of trouble sleeping (OR: 0.26, 95% CI: 0.10-0.67, p = 0.006), and this association was seen in men (OR: 0.23, 95% CI: 0.09-0.56, p = 0.002), but was not seen in women (OR: 0.71, 95% CI: 0.27-1.88, p = 0.500). Restricted cubic spline analysis showed that the incidence of trouble sleeping gradually decreased after at least 105 min of moderate-intensity PA per week in participants (OR: 1.02, 95% CI: 0.92-1.14). A significant difference appeared after 341 min (OR: 0.87, 95% CI: 0.76-0.99), and the curve leveled after 1,250 min (OR: 0.60, 95% CI: 0.46-0.79). Conclusion: Our findings observed associations between PA and sleep condition in the adult ADHD patients with stimulant medication use population. Moderate-to-vigorous PA may be beneficial to sleep in adults with ADHD who were using stimulants and thus should be recommended as part of a healthy lifestyle. Gender difference should be considered as an important factor for further studies to examine these associations and explore potential mechanisms.

8.
Parasit Vectors ; 16(1): 455, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38098083

RESUMEN

BACKGROUND: Despite years of effort to develop an effective vaccine against malaria infection, a vaccine that provides individuals with sufficient protection against malaria illness and death in endemic areas is not yet available. The development of transmission-blocking vaccines (TBVs) is a promising strategy for malaria control. A dual-antigen malaria vaccine targeting both pre- and post-fertilization antigens could effectively improve the transmission-blocking activity of vaccines against the sexual stages of the parasite. METHODS: A chimeric recombinant protein Pb22-Pbg37 (Plasmodium berghei 22-P. berghei G37) composed of 19-218 amino acids (aa) of Pb22 and the N-terminal 26-88 aa of Pbg37 was designed and expressed in the Escherichia coli expression system. The antibody titers of the fusion (Pb22-Pbg37) and mixed (Pb22+Pbg37) antigens, as well as those of Pb22 and Pbg37 single antigens were evaluated by enzyme-linked immunosorbent assay. Immunofluorescence and western blot assays were performed to test the reactivity of the antisera with the native proteins in the parasite. The induction of transmission-blocking activity (TBA) by Pb22-Pbg37 and Pb22+Pbg37 were evaluated by in vitro gametocyte activation, gamete and exflagellation center formation, ookinete conversion, and in the direct mosquito feeding assay. RESULTS: The Pb22-Pbg37 fusion protein was successfully expressed in vitro. Co-administration of Pb22 and Pbg37 as a fusion or mixed protein elicited comparable antibody responses in mice and resulted in responses to both antigens. Most importantly, both the mixed and fusion antigens induced antibodies with significantly higher levels of TBA than did each of the individual antigens when administered alone. In addition, the efficacy of vaccination with the Pb22-Pbg37 fusion protein was equivalent to that of vaccination with the mixed single antigens. CONCLUSIONS: Dual-antigen vaccines, which expand/lengthen the period during which the transmission-blocking antibodies can act during sexual-stage development, can provide a promising higher transmission-reducing activity compared to single antigens.


Asunto(s)
Vacunas contra la Malaria , Malaria , Ratones , Animales , Vacunas contra la Malaria/genética , Proteínas Protozoarias/metabolismo , Malaria/parasitología , Vacunación , Proteínas Recombinantes , Anticuerpos Antiprotozoarios , Antígenos de Protozoos/genética , Plasmodium falciparum
9.
Int J Mol Sci ; 24(22)2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-38003364

RESUMEN

Mammary fat plays a profound role in the postnatal development of mammary glands. However, the specific types (white, brown, or beige) of adipocytes in mammary fat and their potential regulatory effects on modulating mammary gland development remain poorly understood. This study aimed to investigate the role of the browning of mammary fat on pubertal mammary gland development and explore the underlying mechanisms. Thus, the mammary gland development and the serum lipid profile were evaluated in mice treated with CL316243, a ß3-adrenoceptor agonist, to induce mammary fat browning. In addition, the proliferation of HC11 cells co-cultured with brown adipocytes or treated with the altered serum lipid metabolite was determined. Our results showed that the browning of mammary fat by injection of CL316243 suppressed the pubertal development of mice mammary glands, accompanied by the significant elevation of serum dioleoylphosphocholine (DOPC). In addition, the proliferation of HC11 was repressed when co-cultured with brown adipocytes or treated with DOPC. Furthermore, DOPC suppressed the activation of the PI3K/Akt pathway, while the DOPC-inhibited HC11 proliferation was reversed by SC79, an Akt activator, suggesting the involvement of the PI3K/Akt pathway in the DOPC-inhibited proliferation of HC11. Together, the browning of mammary fat suppressed the development of the pubertal mammary gland, which was associated with the elevated serum DOPC and the inhibition of the PI3K/Akt pathway.


Asunto(s)
Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Adipocitos Marrones/metabolismo , Lecitinas/farmacología
11.
Eur J Pharmacol ; 960: 176159, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37898287

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) is a major liver disease subtype worldwide, is commonly associated with insulin resistance and obesity. NAFLD is characterized by an excessive hepatic lipid accumulation, as well as hepatic steatosis. Fenofibrate is a peroxisome proliferator-activated receptor α agonist widely used in clinical therapy to effectively ameliorate the development of NAFLD, but its mechanism of action is incompletely understood. Here, we found that fenofibrate dramatically modulate the gut microbiota composition of high-fat diet (HFD)-induced NAFLD mouse model, and the change of gut microbiota composition is dependent on TFEB-autophagy axis. Furthermore, we also found that fenofibrate improved hepatic steatosis, and increased the activation of TFEB, which severed as a regulator of autophagy, thus, the protective effects of fenofibrate against NAFLD are depended on TFEB-autophagy axis. Our study demonstrates the host gene may influence the gut microbiota and highlights the role of TFEB and autophagy in the protective effect of NAFLD. This work expands our understanding of the regulatory interactions between the host and gut microbiota and provides novel strategies for alleviating obesity.


Asunto(s)
Fenofibrato , Microbioma Gastrointestinal , Resistencia a la Insulina , Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Fenofibrato/farmacología , Fenofibrato/uso terapéutico , Resistencia a la Insulina/genética , Hígado , Obesidad/tratamiento farmacológico , Dieta Alta en Grasa/efectos adversos , Autofagia , Ratones Endogámicos C57BL
12.
Transl Psychiatry ; 13(1): 300, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37770471

RESUMEN

Depression is highly prevalent and easily relapses. Psychological interventions are effective for the prevention of depression relapse. This systematic review and network meta-analysis aimed to compare the efficacy at the same follow-up time points of psychological interventions in depression. We searched PubMed, Embase, and PsycINFO via OVID, and the Cochrane Library published up to December 12, 2021, and PubMed up to July 1, 2022. The primary outcome was depression relapse, considering the same time points that were extracted on survival curves or relapse curves. The study protocol was registered with PROSPERO, CRD42022343327. A total of 2,871 patients were included from 25 RCTs. Mindfulness-based cognitive therapy (MBCT) was significantly better than placebo at the 3 months, the 6 months, and the 9 months at follow-up. Cognitive behavioral therapy (CBT) was significantly better than treatment as usual at the 3 months, the 9 months, the 12 months, and the 15 months at follow-up. CBT was significantly better than placebo at the 21 months and the 24 months at follow-up. Behavioral activation therapy was significantly better than placebo at the 21 months and the 24 months at follow-up. Interpersonal psychotherapy was significantly better than placebo at the 24-month follow-up. All psychological interventions included in the study were significantly better than supportive counseling most of the time. The results were robust in various sensitivity and subgroup analyses. In conclusion, MBCT had a continuous effect in preventing relapse of depression. CBT had the longest but not continuous effect in preventing relapse of depression. The effects of behavioral activation therapy and interpersonal therapy for the prevention of depression appeared late. All psychological interventions included in the study were more effective than supportive counseling. More evidence is needed from large comparative trials that provide long-term follow-up data.


Asunto(s)
Depresión , Intervención Psicosocial , Humanos , Metaanálisis en Red , Depresión/prevención & control , Terapia Conductista , Enfermedad Crónica , Recurrencia
13.
Dalton Trans ; 52(35): 12194-12197, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37606299

RESUMEN

Photomechanical crystals are promising candidates for photo actuators due to their ability to convert light energy into mechanical energy. We synthesized a coordination polymer crystal that can undergo [4 + 4] cycloaddition reactions with mechanical motion. The inclusion of {[ZnL2(4,4'-bipy)(CH3OH)2]}∞ in a polymer membrane significantly magnified the actuation behavior.

14.
Biochim Biophys Acta Gene Regul Mech ; 1866(4): 194965, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37524226

RESUMEN

Osteoarthritis (OA) is the most common irreversible chronic joint dysfunction disease, which is pathologically characterized by disturbance of articular cartilage homeostasis leading to subsequent inflammatory response and cartilage extracellular matrix (ECM) degradation. Increasing evidence has demonstrated the dysregulation of transcription factors play crucial roles in the occurrence and development of osteoarthritis (OA), but the potential functions and mechanism of most transcription factors in OA has not been completely illuminated. In this study, we identified that transcription factor V-ets erythroblastosis virus E26 oncogene homolog 2 (ETS2) was significantly down-regulated in OA cartilage and IL-1ß-induced OA chondrocytes. Functional experiments in vitro demonstrated that the overexpressed ETS2 strikingly enhanced proliferation, outstandingly suppressed apoptosis, and dramatically reduced inflammation and ECM degradation in IL-1ß-induced OA chondrocytes, whereas the knockdown of ETS2 led to the opposite effects. Further in vivo studies have shown that up-regulated ETS2 dramatically ameliorates cartilage injury in DMM-induced OA mice. Mechanical studies have disclosed that DNMT1-mediated downregulation of ETS2 dramatically promotes STAT1 by inhibiting miR-155 transcription, and increased STAT1 initiates a feedback loop that may enhance DNMT1-mediated hypermethylation of ETS2 to inhibit ETS2 expression, thus forming a DNMT1/ETS2/miR-155/STAT1 feedback loop that inhibits MAPK signaling pathways and aggravates OA cartilage injury. In all, our results revealed that overexpression of ETS2 markedly ameliorated OA cartilage injury through the ETS2/miR-155/STAT1/DNMT1 feedback loop, providing a new perspective on the pathogenesis and therapeutic strategies for OA.


Asunto(s)
Cartílago Articular , MicroARNs , Osteoartritis , Ratones , Animales , MicroARNs/genética , MicroARNs/metabolismo , Retroalimentación , Osteoartritis/genética , Osteoartritis/metabolismo , Osteoartritis/patología , Cartílago Articular/metabolismo , Cartílago Articular/patología , Factores de Transcripción/metabolismo
15.
Front Psychol ; 14: 1136878, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37441337

RESUMEN

Introduction: The quality of student engagement in assessment within higher education affects learning outcomes. However, variations in conceptions of what quality in engagement looks like impacts assessment design and the way that students and lecturers engage with each other in the assessment process. Given that assessment is an important driver of student engagement in higher education, it is surprising that no specific measures to support understanding of this measure exist. To address this significant gap, we outline the evolution of an assessment engagement scale derived from a research-informed conceptual framework utilizing best practice in assessment and feedback. Methods: We consider the validity and utility of the assessment engagement scale in supporting students' understanding of assessment and their role within it using exploratory and confirmatory factor analyses. Results: The resultant nine-item assessment engagement scale's underpinning two factors included: (i) Understanding of the Assessment Context (UAC) including one's role within it, and confidence in navigating assessment requirement, and (ii) Realising Engagement Opportunities (REO) (i.e., willingness to engage and ability to utilise the assessment context effectively to support one's understanding). Construct, criterion, and convergent validity of the scale were established. Discussion: The AES is a powerful tool in promoting dialogue between lecturers and students about what high quality engagement in assessment looks like, and the respective roles of all parties in realising this. Implications for assessment practices are discussed along with the potential of the scale as a predictive and developmental tool to support enhancements in assessment design and student learning outcomes in higher education.

16.
Mol Metab ; 73: 101747, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37279828

RESUMEN

OBJECTIVE: Brown adipose tissue (BAT) plays a crucial role in regulating non-shivering thermogenesis under cold exposure. Proline hydroxylases (PHDs) were found to be involved in adipocyte differentiation and lipid deposition. However, the effects of PHDs on regulatory mechanisms of BAT thermogenesis are not fully understood. METHODS: We detected the expression of PHDs in different adipose tissues by using immunoblotting and real-time PCR. Further, immunoblotting, real-time PCR, and immunostaining were performed to determine the correlation between proline hydroxylase 2 (PHD2) and UCP1 expression. Inhibitor of PHDs and PHD2-sgRNA viruses were used to construct the PHD2-deficiency model in vivo and in vitro to investigate the impacts of PHD2 on BAT thermogenesis. Afterward, the interaction between UCP1 and PHD2 and the hydroxylation modification level of UCP1 were verified by Co-IP assays and immunoblotting. Finally, the effect of specific proline hydroxylation on the expression/activity of UCP1 was further confirmed by site-directed mutation of UCP1 and mass spectrometry analysis. RESULTS: PHD2, but not PHD1 and PHD3, was highly enriched in BAT, colocalized, and positively correlated with UCP1. Inhibition or knockdown of PHD2 significantly suppressed BAT thermogenesis under cold exposure and aggravated obesity of mice fed HFD. Mechanistically, mitochondrial PHD2 bound to UCP1 and regulated the hydroxylation level of UCP1, which was enhanced by thermogenic activation and attenuated by PHD2 knockdown. Furthermore, PHD2-dependent hydroxylation of UCP1 promoted the expression and stability of UCP1 protein. Mutation of the specific prolines (Pro-33, 133, and 232) in UCP1 significantly mitigated the PHD2-elevated UCP1 hydroxylation level and reversed the PHD2-increased UCP1 stability. CONCLUSIONS: This study suggested an important role for PHD2 in BAT thermogenesis regulation by enhancing the hydroxylation of UCP1.


Asunto(s)
Obesidad , Prolil Hidroxilasas , Animales , Ratones , Tejido Adiposo Pardo/metabolismo , Hidroxilación , Obesidad/metabolismo , Prolina/metabolismo , Prolil Hidroxilasas/metabolismo , Termogénesis/fisiología
17.
Virulence ; 14(1): 2223060, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37326479

RESUMEN

Riemerella anatipestifer is an important bacterial pathogen in poultry. Pathogenic bacteria recruit host complement factors to resist the bactericidal effect of serum complement. Vitronectin (Vn) is a complementary regulatory protein that inhibits the formation of the membrane attack complex (MAC). Microbes use outer membrane proteins (OMPs) to hijack Vn for complement evasion. However, the mechanism by which R. anatipestifer achieves evasion is unclear. This study aimed to characterise OMPs of R. anatipestifer which interact with duck Vn (dVn) during complement evasion. Far-western assays and comparison of wild-type and mutant strains that were treated with dVn and duck serum demonstrated particularly strong binding of OMP76 to dVn. These data were confirmed with Escherichia coli strains expressing and not expressing OMP76. Combining tertiary structure analysis and homology modelling, truncated and knocked-out fragments of OMP76 showed that a cluster of critical amino acids in an extracellular loop of OMP76 mediate the interaction with dVn. Moreover, binding of dVn to R. anatipestifer inhibited MAC deposition on the bacterial surface thereby enhancing survival in duck serum. Virulence of the mutant strain ΔOMP76 was attenuated significantly relative to the wild-type strain. Furthermore, adhesion and invasion abilities of ΔOMP76 decreased, and histopathological changes showed that ΔOMP76 was less virulent in ducklings. Thus, OMP76 is a key virulence factor of R. anatipestifer. The identification of OMP76-mediated evasion of complement by recruitment of dVn contributes significantly to the understanding of the molecular mechanism by which R. anatipestifer escapes host innate immunity and provides a new target for the development of subunit vaccines.


Asunto(s)
Infecciones por Flavobacteriaceae , Enfermedades de las Aves de Corral , Animales , Virulencia , Patos , Proteínas de la Membrana , Vitronectina , Proteínas Bacterianas/metabolismo , Infecciones por Flavobacteriaceae/microbiología , Infecciones por Flavobacteriaceae/prevención & control , Factores Inmunológicos , Proteínas del Sistema Complemento , Enfermedades de las Aves de Corral/microbiología
18.
J Biol Chem ; 299(6): 104825, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37196766

RESUMEN

Aberrant overexpression of nonreceptor tyrosine kinase FER (Fps/Fes Related) has been reported in various ovarian carcinoma-derived tumor cells and is a poor prognosis factor for patient survival. It plays an essential role in tumor cell migration and invasion, acting concurrently in both kinase-dependent and -independent manners, which is not easily suppressed by conventional enzymatic inhibitors. Nevertheless, the PROteolysis-TArgeting Chimera (PROTAC) technology offers superior efficacy over traditional activity-based inhibitors by simultaneously targeting enzymatic and scaffold functions. Hence in this study, we report the development of two PROTAC compounds that promote robust FER degradation in a cereblon-dependent manner. Both PROTAC degraders outperform a Food and Drug Administration-approved drug, brigatinib, in ovarian cancer cell motility suppression. Importantly, these PROTAC compounds also degrade multiple oncogenic FER fusion proteins identified in human tumor samples. These results lay an experimental foundation to apply the PROTAC strategy to antagonize cell motility and invasiveness in ovarian and other types of cancers with aberrant expression of FER kinase and highlight PROTACs as a superior strategy for targeting proteins with multiple tumor-promoting functions.


Asunto(s)
Neoplasias Ováricas , Proteínas Tirosina Quinasas , Humanos , Femenino , Proteínas Tirosina Quinasas/metabolismo , Quimera Dirigida a la Proteólisis , Proteínas/metabolismo , Neoplasias Ováricas/tratamiento farmacológico , Movimiento Celular , Proteolisis
19.
Microbiol Spectr ; 11(3): e0143423, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37249423

RESUMEN

Cyclic invasion of red blood cells (RBCs) by Plasmodium merozoites is associated with the symptoms and pathology of malaria. Merozoite invasion is powered actively and rapidly by a parasite actomyosin motor called the glideosome. The ability of the glideosome to generate force to support merozoite entry into the host RBCs is thought to rely on its stable anchoring within the inner membrane complex (IMC) through membrane-resident proteins, such as GAP50 and GAP40. Using a conditional knockdown (KD) approach, we determined that PfGAP40 was required for asexual blood-stage replication. PfGAP40 is not needed for merozoite egress from host RBCs or for the attachment of merozoites to new RBCs. PfGAP40 coprecipitates with PfGAP45 and PfGAP50. During merozoite invasion, PfGAP40 is associated strongly with stabilizing the expression levels of PfGAP45 and PfGAP50 in the schizont stage. Although PfGAP40 KD did not influence IMC integrity, it impaired the maturation of gametocytes. In addition, PfGAP40 is phosphorylated, and mutations that block phosphorylation of PfGAP40 at the C-terminal serine residues S370, S372, S376, S405, S409, S420, and S445 reduced merozoite invasion efficiency. Overall, our findings implicate PfGAP40 as an important regulator for the gliding activity of merozoites and suggest that phosphorylation is required for PfGAP40 function. IMPORTANCE Red blood cell invasion is central to the pathogenesis of the malaria parasite, and the parasite proteins involved in this process are potential therapeutic targets. Gliding motility powers merozoite invasion and is driven by a unique molecular motor termed the glideosome. The glideosome is stably anchored to the parasite inner membrane complex (IMC) through membrane-resident proteins. In the present study, we demonstrate the importance of an IMC-resident glideosome component, PfGAP40, that plays a critical role in stabilizing the expression levels of glideosome components in the schizont stage. We determined that phosphorylation of PfGAP40 at C-terminal residues is required for efficient merozoite invasion.


Asunto(s)
Malaria , Plasmodium falciparum , Animales , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Merozoítos/metabolismo , Proteínas Protozoarias/metabolismo , Proteínas de la Membrana/metabolismo , Malaria/parasitología
20.
Phys Chem Chem Phys ; 25(17): 12426-12442, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37096366

RESUMEN

To reduce the environmental pollution caused by organic solvents and improve the extraction efficiency, a range of imidazolium-based ionic liquid (IL) combinations of [Omim]+ paired with [Br]-, [BF4]-, [Cl]-, [ClO4]-, [HsO4]-, [NO3]-, [NTf2]-, [OAc]-, [PF6]-, and [TsO]- are explored for the extraction of camptothecin (CPT) using molecular dynamics (MD) simulation and density functional theory (DFT) calculations. It is found that the ILs containing [Br]-, [OAc]-, and [TsO]- anions are the most promising solvents for CPT solvation because they exhibit stronger interaction energy and the lowest self-diffusion coefficient of CPT among all ILs. The microscopic mechanism at the molecular level is revealed based on DFT calculations and MD simulations, and the results demonstrate that the IL (i.e., [Omim][TsO]) containing anions with strong hydrogen bond (HB) acceptability and aromatic ring structure corresponds to both the strongest van der Waals interaction and strongest HB interaction of CPT-anions. Therefore, it is recommended that anions with aromatic ring structures or strong HB acceptability are promising anion candidates, while anions containing electron withdrawing groups and bulky substituents should be avoided. This work provides intermolecular insight into designing and selecting effective ILs for natural insoluble active pharmaceutical ingredient dissolution and extraction in further research.

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