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1.
J Dent ; 145: 105024, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670332

RESUMO

OBJECTIVE: Rapid maxillary expansion is a common orthodontic procedure to correct maxillary constriction. Assessing the midpalatal suture (MPS) expansion plays a crucial role in treatment planning to determine its effectiveness. The objectives of this preliminary investigation are to demonstrate a proof of concept that the palatal bone underlying the rugae can be clearly imaged by ultrasound (US) and the reconstructed axial view of the US image accurately maps the MPS patency. METHODS: An ex-vivo US scanning was conducted on the upper jawbones of two piglet's carcasses before and after the creation of bone defects, which simulated the suture opening. The planar images were processed to enhance bone intensity distribution before being orderly stacked to fuse into a volume. Graph-cut segmentation was applied to delineate the palatal bone to generate a bone volume. The accuracy of the reconstructed bone volume and the suture opening was validated by the micro-computed tomography (µCT) data used as the ground truth and compared with cone beam computed tomography (CBCT) data as the clinical standard. Also included in the comparison is the rugae thickness. Correlation and Bland-Altman plots were used to test the agreement between the two methods: US versus µCT/CBCT. RESULTS: The reconstruction of the US palatal bone volumes was accurate based on surface topography comparison with a mean error of 0.19 mm for pre-defect and 0.15 mm and 0.09 mm for post-defect models of the two samples, respectively when compared with µCT volumes. A strong correlation (R2 ≥ 0.99) in measuring MPS expansion was found between US and µCT/CBCT with MADs of less than 0.05 mm, 0.11 mm and 0.23 mm for US, µCT and CBCT, respectively. CONCLUSIONS: It was possible to axially image the MPS opening and rugae thickness accurately using high-frequency ultrasound. CLINICAL SIGNIFICANCE: This study introduces an ionizing radiation-free, low-cost, and portable technique to accurately image a difficult part of oral cavity anatomy. The advantages of conceivable visualization could promise a successful clinical examination of MPS to support the predictable treatment outcome of maxillary transverse deficiency.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Técnica de Expansão Palatina , Ultrassonografia , Microtomografia por Raio-X , Animais , Suínos , Microtomografia por Raio-X/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Técnica de Expansão Palatina/instrumentação , Ultrassonografia/métodos , Palato/diagnóstico por imagem , Palato/anatomia & histologia , Suturas Cranianas/diagnóstico por imagem , Suturas Cranianas/anatomia & histologia , Maxila/diagnóstico por imagem , Palato Duro/diagnóstico por imagem , Palato Duro/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos
2.
Sci Rep ; 14(1): 3234, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331970

RESUMO

Many polar organisms produce antifreeze proteins (AFPs) and ice-binding proteins (IBPs) to protect themselves from ice formation. As IBPs protect cells and organisms, the potential of IBPs as natural or biological cryoprotective agents (CPAs) for the cryopreservation of animal cells, such as oocytes and sperm, has been explored to increase the recovery rate after freezing-thawing. However, only a few IBPs have shown success in cryopreservation, possibly because of the presence of protein denaturants, such as dimethyl sulfoxide, alcohols, or ethylene glycol, in freezing buffer conditions, rendering the IBPs inactive. Therefore, we investigated the thermal and chemical stability of FfIBP isolated from Antarctic bacteria to assess its suitability as a protein-based impermeable cryoprotectant. A molecular dynamics (MD) simulation identified and generated stability-enhanced mutants (FfIBP_CC1). The results indicated that FfIBP_CC1 displayed enhanced resistance to denaturation at elevated temperatures and chemical concentrations, compared to wildtype FfIBP, and was functional in known CPAs while retaining ice-binding properties. Given that FfIBP shares an overall structure similar to DUF3494 IBPs, which are recognized as the most widespread IBP family, these findings provide important structural information on thermal and chemical stability, which could potentially be applied to other DUF3494 IBPs for future protein engineering.


Assuntos
Proteínas de Transporte , Gelo , Masculino , Animais , Proteínas de Transporte/metabolismo , Sêmen/metabolismo , Bactérias/metabolismo , Congelamento , Proteínas Anticongelantes/química , Crioprotetores/farmacologia , Crioprotetores/metabolismo
3.
Int J Mol Sci ; 24(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37834067

RESUMO

Virus-like particles (VLPs) have been proposed as an attractive tool in SARS-CoV-2 vaccine development, both as (1) a vaccine candidate with high immunogenicity and low reactogenicity and (2) a substitute for live virus in functional and neutralization assays. Though multiple SARS-CoV-2 VLP designs have already been explored in Sf9 insect cells, a key parameter ensuring VLPs are a viable platform is the VLP spike yield (i.e., spike protein content in VLP), which has largely been unreported. In this study, we show that the common strategy of producing SARS-CoV-2 VLPs by expressing spike protein in combination with the native coronavirus membrane and/or envelope protein forms VLPs, but at a critically low spike yield (~0.04-0.08 mg/L). In contrast, fusing the spike ectodomain to the influenza HA transmembrane domain and cytoplasmic tail and co-expressing M1 increased VLP spike yield to ~0.4 mg/L. More importantly, this increased yield translated to a greater VLP spike antigen density (~96 spike monomers/VLP) that more closely resembles that of native SARS-CoV-2 virus (~72-144 Spike monomers/virion). Pseudotyping further allowed for production of functional alpha (B.1.1.7), beta (B.1.351), delta (B.1.617.2), and omicron (B.1.1.529) SARS-CoV-2 VLPs that bound to the target ACE2 receptor. Finally, we demonstrated the utility of pseudotyped VLPs to test neutralizing antibody activity using a simple, acellular ELISA-based assay performed at biosafety level 1 (BSL-1). Taken together, this study highlights the advantage of pseudotyping over native SARS-CoV-2 VLP designs in achieving higher VLP spike yield and demonstrates the usefulness of pseudotyped VLPs as a surrogate for live virus in vaccine and therapeutic development against SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Anticorpos Antivirais , Vacinas contra COVID-19 , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/prevenção & controle , Anticorpos Neutralizantes
4.
Gels ; 9(10)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37888358

RESUMO

Several previous studies in the field of assisted reproduction have focused on the use of blood gel derivatives, such as platelet-rich fibrin (PRF), as a treatment for endometrial rehabilitation. However, the ability to release growth factors and the gel form of this product led to the evolution of platelet lysates. In this study, blood gel derivatives, including PRF lysate, which was in liquid form, and PRF gel, were collected and evaluated for growth factors. It was shown to be effective in endometrial wound healing and regeneration in mouse injured uterine tissue models through structure and function (pinopode expression, embryo implantation) evaluation. The results demonstrated that the concentrations of growth factors, including PDGF-AB and VEGF-A, were higher in the PRF lysate compared to the PRF gel (p < 0.05). PRF lysate could release these growth factors for 8 days. Furthermore, both PRF gel and PRF lysate restored the morphology of injured endometrial tissues in terms of luminal and glandular epithelia, as well as uterine gland secretory activity. However, the presence of pinopodes and embryonic implantation were only observed in the PRF lysate group. It can be concluded that PRF lysate promotes wound healing in mouse injured tissue models in vitro, which can act as healing products in tissue repair.

5.
Front Public Health ; 11: 1231326, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37794894

RESUMO

Introduction: The outbreak of coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) had significant effects on the mental well-being in general, particularly for healthcare professionals. This study examined the prevalence of depression, anxiety, and stress, and identified the associated risk factors amongst healthcare workers during the COVID-19 outbreak in a tertiary hospital located in Vietnam. Methods: We conducted a cross-sectional study at a tertiary-level hospital, where the Depression Anxiety and Stress Scale 21 (DASS-21) web-based questionnaire was employed. We analyzed the determinant factors by employing multivariate logistic models. Results: The prevalence of depression, anxiety, and stress symptoms were 19.2%, 24.7%, and 13.9%, respectively. Factors such as engaging in shift work during the pandemic, taking care of patients with COVID-19, and staff's health status were associated with mental health issues among health professionals. In addition, having alternate rest periods was likely to reduce the risk of stress. Conclusion: The prevalence of mental health problems in healthcare workers during the COVID-19 pandemic was relatively high. Having resting periods could potentially mitigate the development of stress among health professionals. Our findings could be taken into account for improving mental health of the health professional population.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Estudos Transversais , SARS-CoV-2 , Depressão/epidemiologia , RNA Viral , Centros de Atenção Terciária , Vietnã/epidemiologia , Ansiedade/epidemiologia , Pessoal de Saúde/psicologia
6.
Rep Pract Oncol Radiother ; 28(4): 445-453, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795228

RESUMO

Background: The study was to evaluate the effectiveness of dose distribution of four-dimensional computed tomography (4DCT) simulation. Materials and methods: The gross tumor volume (GTV) and clinical target volume (CTV) were contoured in all 10 respiratory phases of 4DCT in 30 patients with non-small cell lung cancer (NSCLC). Both 3D and 4D treatment plans were made individually for each patient using the planning volume (PTV). The PTV3D was taken from a single CTV plus the recommended margin, and the PTV4D was taken from the 4D internal target volume, including all 10 CTVs plus the setup margins. Results: The mean PTV was 460 ± 179 (69-820) cm3 for 3DCT and 401 ± 167 (127-854) cm3 for 4DCT (p = 0.0018). The dose distribution (DD) of organs at risk, especially the lungs, was lower for the 4DCT simulation. The V5%, V10%, and V20% of the total lung dose for 4DCT were significantly lower for the 3DCT. However, lung V30% the heart, esophagus, and spinal cord were not significantly different. In addition, the conformity index and the dose heterogeneity index of the PTV were not significantly different. The normal tissue complication probability (NTCP) of the lung and heart was significantly lower for 4DCT than for 3DCT. Conclusions: The 4DCT simulation gives better results on the NTCP. The organs at risk, especially the lungs, receive a significantly lower DD compared with the 3DCT. The conformity index (CI), heterogeneity index (HI) and the DD to the heart, spinal cord, and esophagus were not significantly different between the two techniques.

7.
PLoS One ; 18(8): e0290686, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37651358

RESUMO

This study investigates the impact of aromatic cluster side-chain interactions in Grx3 (SpGrx3) from the psychrophilic Arctic bacterium Sphingomonas sp. Grx3 is a class I oxidoreductase with a unique parallel arrangement of aromatic residues in its aromatic cluster, unlike the tetrahedral geometry observed in Trxs. Hydrophilic-to-hydrophobic substitutions were made in the aromatic cluster, in ß1 (E5V and Y7F), adjacent ß2 (Y32F and Y32L), both ß1 and ß2 (E5V/Y32L), and short α2 (R47F). The hydrophobic substitutions, particularly those at or near Tyr7 (E5V, Y7F, Y32F, and R47F), increased melting temperatures and conformational stability, whereas disrupting ß1-ß2 interactions (Y32L and E5V/Y32L) led to structural instability of SpGrx3. However, excessive hydrophobic interactions (Y7F and E5V/Y32L) caused protein aggregation at elevated temperatures. All mutations resulted in a reduction in α-helical content and an increase in ß-strand content. The R47F mutant, which formed dimers and exhibited the highest ß-strand content, showed increased conformational flexibility and a significant decrease in catalytic rate due to the disturbance of ß1-α2 interactions. In summary, the configuration of the aromatic cluster, especially Tyr7 in the buried ß1 and Arg47 in the short α2, played crucial roles in maintaining the active conformation of SpGrx3 and preventing its protein aggregation. These modifications, reducing hydrophobicity in the central ß-sheet, distinguish Grx3 from other Trx-fold proteins, highlighting evolutionary divergence within the Trx-fold superfamily and its functional versatility.


Assuntos
Glutarredoxinas , Sphingomonas , Humanos , Agregados Proteicos , Sphingomonas/genética , Evolução Biológica , Febre
8.
Sci Rep ; 13(1): 12310, 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37516760

RESUMO

Numerous ports worldwide are adopting automation to boost productivity and modernize their operations. At this point, smart ports become a more important paradigm for handling increasing cargo volumes and increasing operational efficiency. In fact, as ports become more congested and cargo volumes increase, the need for accurate navigation through seaports is more pronounced to avoid collisions and the resulting consequences. To this end, digital twin (DT) technology in the fifth-generation (5G) networks and drone-assisted data collection can be combined to provide precise ship maneuvering. In this paper, we propose a DT model using drone-assisted data collection architecture, called TwinPort, to offer a comprehensive port management system for smart seaports. We also present a recommendation engine to ensure accurate ship navigation within a smart port during the docking process. The experimental results reveal that our solution improves the trajectory performance by approaching the desired shortest path. Moreover, our solution supports significantly reducing financial costs and protecting the environment by reducing fuel consumption.

9.
Pediatr Blood Cancer ; : e30526, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37355858

RESUMO

OBJECTIVES: To characterize the clinical features, treatment, and outcome of children diagnosed with retinoblastoma (RB) at Vietnam National Cancer Hospital. METHODS: The study enrolled all RB patients newly diagnosed at Vietnam National Cancer Hospital from January 2018 to December 2022. The primary endpoint was overall survival (OS) and the eye salvage rate. RESULTS: In total, 139 patients were enrolled, 51.8% patients were male. Median age was 18.9 months. Most patients presented with leukocoria (63.3%), followed by strabismus (14.4%), and 43.9% had bilateral disease. Of 200 eyes, 129 (64.5%) were classified as group E. Extraocular extension was noted in 10 of 139 patients (7.2%). About one-third of the patients lived more than 300 kilometers (km) away from these hospitals, and 17.3% of the patients belonged to minority groups, both of which were dominated by group E and extraocular or high-risk eyes at the time of consultation. Primary enucleation was done for 57 eyes (28.5%), and 51 of 61 patients (83.6%) received eye salvage therapy in bilateral RB group. At study closure, 127 children were alive at the last follow-up, 12 cases were confirmed dead. The 5-year OS and progression-free survival (PFS) rates were 90.3% and 85.9%, respectively. In particular, ethnic minority, distance to hospital more than 150 km, and extraocular disease were significantly associated with higher mortality among children with RB treated in Vietnam National Cancer Hospital. CONCLUSIONS: There is a need to support for screening RB with early symptoms in grassroots medical facilities and raise awareness among patients' families through health education programs. Besides, caring and supporting treatment for patients from the ethnic minority and who live far from hospitals are also extremely necessary.

10.
BMC Pregnancy Childbirth ; 23(1): 301, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37118695

RESUMO

BACKGROUND: Cervical length (CL) measured by ultrasound in the second trimester is a predictor of spontaneous preterm birth (sPTB). The uterocervical angle (UCA) has recently been suggested as a predictor to identify women at risk of sPTB. The aim of this study was to investigate the UCAs' distribution in singleton pregnant women at 16+ 0 - 23+ 6 weeks of gestation with low risk for sPTB. METHODS: This was a prospective cohort study of 1,051 pregnant women with singleton pregnancies at low risk for preterm delivery. Pregnant women with a viable singleton fetus at 16+ 0 - 23+ 6 weeks of gestation were enrolled in the study conducted at the Haiphong Hospital of Obstetrics and Gynecology, Vietnam, from 09/2019 to 09/2020. CL and the UCA were assessed using transvaginal ultrasonography (TVS) by a single sonographer. Subjects were followed-up until the end of pregnancy, and maternal and neonatal outcomes were recorded. The UCAs' range and their relationship with gestational age were evaluated using regression analysis. P < 0.05 was considered statistically significant. RESULTS: The normal range of the UCA (5th - 95th percentiles) was 46.47° (95% CI, 40.27°-51.81°) to 127.06° (95% CI, 123.02° - 130.71°). The UCAs in the preterm birth (< 37 weeks) and full-term groups were 117.86° ± 20.25° and 83.80° ± 24.18°, respectively (p < 0.001). Linear regression analysis showed a significant change in the UCA range from 16+ 0 to 23+ 6 weeks of gestation (2.51 degrees per week, p < 0.001). The linear function yielded the highest correlation coefficient in the variation rule of the UCA values (r = 0.22). A total of 42/63 (66.7%) patients with preterm birth < 37 weeks had a UCA above the 75th percentile. The majority of women with preterm birth had a UCA ≥ 95° compared with those with full-term delivery (88.9% vs. 31.3%, p < 0.001). CONCLUSIONS: The results of this study present background information about the normal range of UCA values in singleton pregnant women at 16+ 0 to 23+ 6 weeks at low risk for sPTB in this Vietnamese cohort. In this study population at low risk for sPTB, pregnant women with a UCA value ≥ 95o were also considered at risk for preterm birth.


Assuntos
Nascimento Prematuro , Feminino , Gravidez , Humanos , Recém-Nascido , Nascimento Prematuro/epidemiologia , Gestantes , Estudos Prospectivos , Idade Gestacional , População do Sudeste Asiático , Vietnã/epidemiologia , Medida do Comprimento Cervical , Colo do Útero/diagnóstico por imagem
11.
Cancers (Basel) ; 15(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36765626

RESUMO

We previously reported that NOD.Scid mice lacking interleukin-15 (IL-15), or IL-15 receptor alpha-chain, develop T-acute lymphoblastic leukemia (T-ALL). To understand the mechanisms by which IL-15 signaling controls T-ALL development, we studied the thymocyte developmental events in IL-15-deficient Scid mice from NOD and C57BL/6 genetic backgrounds. Both kinds of mice develop T-ALL characterized by circulating TCR-negative cells expressing CD4, CD8 or both. Analyses of thymocytes in NOD.Scid.Il15-/- mice prior to T-ALL development revealed discernible changes within the CD4-CD8- double-negative (DN) thymocyte developmental stages and increased frequencies of CD4+CD8+ double-positive cells with a high proportion of TCR-negative CD4+ and CD8+ cells. The DN cells also showed elevated expressions of CXCR4 and CD117, molecules implicated in the expansion of DN thymocytes. T-ALL cell lines and primary leukemic cells from IL-15-deficient NOD.Scid and C57BL/6.Scid mice displayed increased NOTCH1 activation that was inhibited by NOTCH1 inhibitors and blockers of the PI3K/AKT pathway. Primary leukemic cells from NOD.Scid.Il15-/- mice survived and expanded when cultured with MS5 thymic stromal cells expressing Delta-like ligand 4 and supplemented with IL-7 and FLT3 ligand. These findings suggest that IL-15 signaling in the thymus controls T-ALL development from aberrant thymocytes with an impaired DNA repair capacity and increased NOTCH1 activation.

12.
FEBS Open Bio ; 13(3): 500-510, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36680400

RESUMO

Glutaredoxins (Grxs) are small proteins that share a well-conserved thioredoxin (Trx)-fold and participate in many biological processes. This study examined the cold adaptation mechanism of a Fe-S cluster binding class II Grx4 (SpGrx4) from the psychrophilic Arctic bacterium Sphingomonas sp. PAMC 26621. Three polar residues close to the cis-proline residue (P73) of SpGrx4 form a hydrogen bond network (Q74-S67-Y76) with the cis-proline loop main chain. The hydroxyl group of S67 or Y76 or both is replaced in similar Grxs depending on the temperature of the habitat. Mutants with reduced hydrogen bonds (S67A, Q74A, Y76F, and S67A/Y76W) were more susceptible to urea-induced unfolding and more flexible than the wild-type (WT). By contrast, Y76W, with a bulky indole group, was the most stable. These mutants showed higher melting temperatures than WT as a consequence of increased hydrophobic interactions. These results suggest that the tyrosine residue, Y76, is preferred for the cold adaptation of SpGrx4 with a heat-labile structure despite the rigid cis-proline loop, due to hydrogen bond formation. An aromatic residue on ß3 (cis-proline plus3) modulates the stability-flexibility of the cis-proline loop for temperature adaptation of prokaryotic class II Grx4 members via hydrogen bonds and hydrophobic interactions.


Assuntos
Sphingomonas , Sphingomonas/genética , Glutarredoxinas/genética , Temperatura Alta , Proteínas , Prolina/química
13.
Commun Biol ; 5(1): 961, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104445

RESUMO

The Ets transcription factor PU.1 is essential for inducing the differentiation of monocytes, macrophages, and B cells in fetal liver and adult bone marrow. PU.1 controls hematopoietic differentiation through physical interactions with other transcription factors, such as C/EBPα and the AP-1 family member c-Jun. We found that PU.1 recruits c-Jun to promoters without the AP-1 binding sites. To address the functional importance of this interaction, we generated PU.1 point mutants that do not bind c-Jun while maintaining normal DNA binding affinity. These mutants lost the ability to transactivate a target reporter that requires a physical PU.1-c-Jun interaction, and did not induce monocyte/macrophage differentiation of PU.1-deficient cells. Knock-in mice carrying these point mutations displayed an almost complete block in hematopoiesis and perinatal lethality. While the PU.1 mutants were expressed in hematopoietic stem and early progenitor cells, myeloid differentiation was severely blocked, leading to an almost complete loss of mature hematopoietic cells. Differentiation into mature macrophages could be restored by expressing PU.1 mutant fused to c-Jun, demonstrating that a physical PU.1-c-Jun interaction is crucial for the transactivation of PU.1 target genes required for myeloid commitment and normal PU.1 function in vivo during macrophage differentiation.


Assuntos
Hematopoese , Fator de Transcrição AP-1 , Animais , Sítios de Ligação , Diferenciação Celular/genética , Hematopoese/genética , Camundongos , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-jun , Fator de Transcrição AP-1/genética
14.
Sci Rep ; 12(1): 13235, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918413

RESUMO

Eukaryotes express a multi-component fatty acid elongase to produce very long chain fatty acids (VLCFAs), which are building blocks of diverse lipids. Elongation is achieved by cyclical iteration of four reactions, the first of which generates a new carbon-carbon bond, elongating the acyl-chain. This reaction is catalyzed by either ELONGATION DEFECTIVE LIKE (ELO) or 3-ketoacyl-CoA synthase (KCS) enzymes. Whereas plants express both ELO and KCS enzymes, other eukaryotes express only ELOs. We explored the Zea mays KCS enzymatic redundancies by expressing each of the 26 isozymes in yeast strains that lacked endogenous ELO isozymes. Expression of the 26 maize KCS isozymes in wild-type, scelo2 or scelo3 single mutants did not affect VLCFA profiles. However, a complementation screen of each of the 26 KCS isozymes revealed five that were capable of complementing the synthetically lethal scelo2; scelo3 double mutant. These rescued strains express novel VLCFA profiles reflecting the different catalytic capabilities of the KCS isozymes. These novel strains offer a platform to explore the relationship between VLCFA profiles and cellular physiology.


Assuntos
Isoenzimas , Saccharomyces cerevisiae , Carbono/metabolismo , Coenzima A/metabolismo , Ácidos Graxos/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
15.
Front Immunol ; 13: 867443, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401501

RESUMO

Early T-cell development is precisely controlled by E proteins, that indistinguishably include HEB/TCF12 and E2A/TCF3 transcription factors, together with NOTCH1 and pre-T cell receptor (TCR) signalling. Importantly, perturbations of early T-cell regulatory networks are implicated in leukemogenesis. NOTCH1 gain of function mutations invariably lead to T-cell acute lymphoblastic leukemia (T-ALL), whereas inhibition of E proteins accelerates leukemogenesis. Thus, NOTCH1, pre-TCR, E2A and HEB functions are intertwined, but how these pathways contribute individually or synergistically to leukemogenesis remain to be documented. To directly address these questions, we leveraged Cd3e-deficient mice in which pre-TCR signaling and progression through ß-selection is abrogated to dissect and decouple the roles of pre-TCR, NOTCH1, E2A and HEB in SCL/TAL1-induced T-ALL, via the use of Notch1 gain of function transgenic (Notch1ICtg) and Tcf12+/- or Tcf3+/- heterozygote mice. As a result, we now provide evidence that both HEB and E2A restrain cell proliferation at the ß-selection checkpoint while the clonal expansion of SCL-LMO1-induced pre-leukemic stem cells in T-ALL is uniquely dependent on Tcf12 gene dosage. At the molecular level, HEB protein levels are decreased via proteasomal degradation at the leukemic stage, pointing to a reversible loss of function mechanism. Moreover, in SCL-LMO1-induced T-ALL, loss of one Tcf12 allele is sufficient to bypass pre-TCR signaling which is required for Notch1 gain of function mutations and for progression to T-ALL. In contrast, Tcf12 monoallelic deletion does not accelerate Notch1IC-induced T-ALL, indicating that Tcf12 and Notch1 operate in the same pathway. Finally, we identify a tumor suppressor gene set downstream of HEB, exhibiting significantly lower expression levels in pediatric T-ALL compared to B-ALL and brain cancer samples, the three most frequent pediatric cancers. In summary, our results indicate a tumor suppressor function of HEB/TCF12 in T-ALL to mitigate cell proliferation controlled by NOTCH1 in pre-leukemic stem cells and prevent NOTCH1-driven progression to T-ALL.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Humanos , Camundongos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptores de Antígenos de Linfócitos T , Proteína 1 de Leucemia Linfocítica Aguda de Células T , Linfócitos T/metabolismo , Fatores de Transcrição/metabolismo
16.
Clin Immunol ; 237: 108980, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35296428

RESUMO

Neuropsychiatric systemic lupus erythematosus (NPSLE) varies in presentation and is one of the leading causes of morbidity and mortality among patients with SLE. This study determined the most critical serum biomarkers for the development of NPSLE as they may have clinical utility prior to the onset of neuropsychiatric symptoms. We retrospectively analyzed 35 NPSLE patients, 34 SLE patients, 20 viral meningitis (VM) patients, and 16 relapsing-remitting multiple sclerosis (MS) patients. We measured anti-suprabasin antibodies concentrations in serum by using Luciferase immunoprecipitation system (LIPS) assay. The serum concentrations of cytokines/chemokines were measured by using multiplex bead-based assay. We found serum FGF-2 level was significantly higher in the NPSLE group compared to the SLE group and the healthy control group. The anti-suprabasin antibody relative concentration (SRC) has high positive predictive values for the development of NPSLE. The most essential biomarkers are VEGF, anti-suprabasin antibodies, sCD40L, IL-10, GRO, MDC, IL-8, IL-9, TNF-α, MIP-1α.


Assuntos
Lúpus Eritematoso Sistêmico , Vasculite Associada ao Lúpus do Sistema Nervoso Central , Biomarcadores , Quimiocinas , Citocinas , Humanos , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico , Estudos Retrospectivos
17.
Semin Cancer Biol ; 86(Pt 3): 1143-1157, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34182141

RESUMO

The intentional use of viruses for cancer therapy dates back over a century. As viruses are inherently immunogenic and naturally optimized delivery vehicles, repurposing viruses for drug delivery, tumor antigen presentation, or selective replication in cancer cells represents a simple and elegant approach to cancer treatment. While early virotherapy was fraught with harsh side effects and low response rates, virus-based therapies have recently seen a resurgence due to newfound abilities to engineer and tune oncolytic viruses, virus-like particles, and virus-mimicking nanoparticles for improved safety and efficacy. However, despite their great potential, very few virus-based therapies have made it through clinical trials. In this review, we present an overview of virus-inspired approaches for cancer therapy, discuss engineering strategies to enhance their mechanisms of action, and highlight their application for overcoming the challenges of traditional cancer therapies.


Assuntos
Nanopartículas , Neoplasias , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Vírus Oncolíticos/genética , Imunoterapia
18.
PLoS One ; 16(12): e0261123, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34910731

RESUMO

Thioredoxin (Trx), a small redox protein, exhibits thermal stability at high temperatures regardless of its origin, including psychrophiles. Trxs have a common structure consisting of the central ß-sheet flanked by an aliphatic cluster on one side and an aromatic cluster on the other side. Although the roles of aromatic amino acids in the folding and stability of proteins have been studied extensively, the contributions of aromatic residues to the stability and function of Trx, particularly Trxs from cold-adapted organisms, have not been fully elucidated. This study examined the roles of aromatic amino acids in the aromatic cluster of a Trx from the psychrophilic Arctic bacterium Sphingomonas sp. PAMC 26621 (SpTrx). The aromatic cluster of SpTrx was comprised of W11, F26, F69, and F80, in which F26 at the ß2 terminus was buried inside. The substitution of tyrosine for F26 changed the SpTrx conformation substantially compared to that of F69 and F80. Further biochemical and spectroscopic investigations on F26 showed that the F26Y, F26W, and F26A mutants resulted in structural instability of SpTrx in both urea- and temperature-induced unfolding and lower insulin reduction activities. The Trx reductase (SpTR) showed lower catalytic efficiencies against F26 mutants compared to the wild-type SpTrx. These results suggest that buried F26 is essential for maintaining the active-site conformation of SpTrx as an oxidoreductase and its structural stability for interactions with SpTR at colder temperatures.


Assuntos
Fenilalanina/química , Sphingomonas/química , Tiorredoxinas/química , Sequência de Aminoácidos , Insulina/metabolismo , Cinética , Modelos Moleculares , Mutação , Conformação Proteica , Estabilidade Proteica , Desdobramento de Proteína , Sphingomonas/genética , Tiorredoxinas/genética , Tiorredoxinas/isolamento & purificação , Tirosina/química
19.
Front Plant Sci ; 12: 770062, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35222448

RESUMO

Hairy root induction system has been applied in various plant species as an effective method to study gene expression and function due to its fast-growing and high genetic stability. Recently, these systems have shown to be an effective tool to evaluate activities of CRISPR/Cas9 systems for genome editing. In this study, Rhizobium rhizogenes mediated hairy root induction was optimized to provide an effective tool for validation of plant transformation vector, CRISPR/Cas9 construct activities as well as selection of targeted gRNAs for gene editing in cucumber (Cucumis sativus L.). Under the optimized conditions including OD650 at 0.4 for infection and 5 days of co-cultivation, the highest hairy root induction frequency reached 100% for the cucumber variety Choka F1. This procedure was successfully utilized to overexpress a reporter gene (gus) and induce mutations in two Lotus japonicus ROOTHAIRLESS1 homolog genes CsbHLH66 and CsbHLH82 using CRISPR/Cas9 system. For induced mutation, about 78% of transgenic hairy roots exhibited mutant phenotypes including sparse root hair and root hair-less. The targeted mutations were obtained in individual CsbHLH66, CsbHLH82, or both CsbHLH66 and CsbHLH82 genes by heteroduplex analysis and sequencing. The hairy root transformation system established in this study is sufficient and potential for further research in genome editing of cucumber as well as other cucumis plants.

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