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1.
PeerJ ; 12: e17350, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827297

RESUMO

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer-related deaths, with very limited therapeutic options available. This study aims to comprehensively depict the heterogeneity and identify prognostic targets for PDAC with single-cell RNA sequencing (scRNA-seq) analysis. Methods: ScRNA-seq analysis was performed on 16 primary PDAC and three adjacent lesions. A series of analytical methods were applied for analysis in cell clustering, gene profiling, lineage trajectory analysis and cell-to-cell interactions. In vitro experiments including colony formation, wound healing and sphere formation assay were performed to assess the role of makers. Results: A total of 32,480 cells were clustered into six major populations, among which the ductal cell cluster expressing high copy number variants (CNVs) was defined as malignant cells. Malignant cells were further subtyped into five subgroups which exhibited specific features in immunologic and metabolic activities. Pseudotime trajectory analysis indicated that components of various oncogenic pathways were differentially expressed along tumor progression. Furthermore, intensive substantial crosstalk between ductal cells and stromal cells was identified. Finally, genes (REG4 and SPINK1) screened out of differentially expressed genes (DEGs) were upregulated in PDAC cell lines. Silencing either of them significantly impaired proliferation, invasion, migration and stemness of PDAC cells. Conclusions: Our findings offer a valuable resource for deciphering the heterogeneity of malignant ductal cells in PDAC. REG4 and SPINK1 are expected to be promising targets for PDAC therapy.


Assuntos
Carcinoma Ductal Pancreático , Lectinas Tipo C , Neoplasias Pancreáticas , Análise de Célula Única , Transcriptoma , Inibidor da Tripsina Pancreática de Kazal , Humanos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/mortalidade , Inibidor da Tripsina Pancreática de Kazal/genética , Inibidor da Tripsina Pancreática de Kazal/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/metabolismo , Prognóstico , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Feminino , Masculino , Proteínas Associadas a Pancreatite
2.
J Diabetes Complications ; 38(6): 108743, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38688179

RESUMO

AIM: This systematic review and meta-analysis aimed to comprehensively evaluate the impact of glucagon-like peptide 1 receptor agonists (GLP-1RAs) on visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in individuals with diabetes mellitus and non-alcoholic fatty liver disease (NAFLD) or obesity. METHODS: A search of PubMed, Embase, and Web of Science until October 2023 identified 13 Randomized Controlled Trials (RCTs) meeting the inclusion criteria. Bias risk was assessed using the Cochrane risk-of-bias instrument. Statistical analysis utilized standard mean differences (SMD) in Review Manager 5.4. Heterogeneity and publication bias were assessed. This study used the protocol registered with the Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY2023110020). RESULTS: GLP-1RA treatment significantly reduced VAT (SMD -0.55, 95 % CI [-0.90, -0.19]), SAT (SMD -0.59, 95 % CI [-0.99, -0.19]), body weight (SMD -1.07, 95 % CI [-1.67, -0.47]), and body mass index (BMI) (SMD -1.10, 95 % CI [-1.74, -0.47]) compared to controls. Heterogeneity was observed for VAT (I2 = 79 %, P < 0.01), SAT (I2 = 73 %, P < 0.01), body weight (I2 = 82 %, P < 0.01), and BMI (I2 = 82 %, P < 0.01). No publication bias was detected for VAT (P = 0.57) and SAT (P = 0.18). GLP-1RA treatment improved fasting blood glucose (FBG), postprandial glucose (PPG), hemoglobin A1c (HbA1c), Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), and fibrosis-4 (FIB-4). CONCLUSIONS: This meta-analysis highlights GLP-1RAs' potential to reduce fat accumulation, body weight, and BMI and improve glycemic control in individuals with diabetes mellitus and NAFLD or obesity. These findings supported using GLP-1RAs as promising therapeutic agents to address abnormal adipose tissue distribution and metabolic dysfunction.


Assuntos
Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hepatopatia Gordurosa não Alcoólica , Obesidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Obesidade/complicações , Obesidade/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Hipoglicemiantes/uso terapêutico , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo , Adiposidade/efeitos dos fármacos , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon
3.
Neuroimage ; 290: 120566, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38467345

RESUMO

OBJECTIVES: Many studies have investigated aberrant functional connectivity (FC) using resting-state functional MRI (rs-fMRI) in subjective tinnitus patients. However, no studies have verified the efficacy of resting-state FC as a diagnostic imaging marker. We established a convolutional neural network (CNN) model based on rs-fMRI FC to distinguish tinnitus patients from healthy controls, providing guidance and fast diagnostic tools for the clinical diagnosis of subjective tinnitus. METHODS: A CNN architecture was trained on rs-fMRI data from 100 tinnitus patients and 100 healthy controls using an asymmetric convolutional layer. Additionally, a traditional machine learning model and a transfer learning model were included for comparison with the CNN, and each of the three models was tested on three different brain atlases. RESULTS: Of the three models, the CNN model outperformed the other two models with the highest area under the curve, especially on the Dos_160 atlas (AUC = 0.944). Meanwhile, the model with the best classification performance highlights the crucial role of the default mode network, salience network, and sensorimotor network in distinguishing between normal controls and patients with subjective tinnitus. CONCLUSION: Our CNN model could appropriately tackle the diagnosis of tinnitus patients using rs-fMRI and confirmed the diagnostic value of FC as measured by rs-fMRI.


Assuntos
Mapeamento Encefálico , Zumbido , Humanos , Mapeamento Encefálico/métodos , Zumbido/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Redes Neurais de Computação
5.
J Prosthodont ; 33(4): 340-347, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37203989

RESUMO

PURPOSE: The aim of this in vitro study was to assess the effects of using different cements and titanium copings designs on the retention of implant-supported fixed dental prostheses (IFDPs) using a pull-out test. MATERIALS AND METHODS: Fifty zirconia (ZirCAD; Ivoclar Vivadent) and 20 prepolymerized denture acrylic resin (AvaDent) rectangular (36 mm × 12 mm × 8 mm) specimens were milled to mimic the lower left segmental portion of the All-on-Four IFDPs. Cylindrical titanium copings (Variobase; Straumann) (V) were used in 2 prepolymerized denture acrylic resin groups (n = 10) while conical titanium copings (Straumann) (C) were used as a control group for zirconia with 4 groups using cylindrical titanium copings. Before cementation, the outer surfaces of all titanium copings and the intaglio bonding surface of prosthetic specimens were airborne-particle abraded. All specimens were cemented following the manufacturer's recommendations and instructions according to the experimental design. After artificial aging (5000 cycles of 5°C 55°C, dwelling time 20 s; 150 N, 1.5 Hz in a 37°C water bath), all specimens were subjected to retention force testing using a pull-out test using a universal testing machine and a custom fixture with a crosshead speed 5 mm/min. Modes of failure were classified as Type 1, 2, or 3. Retention force values were analyzed by the t-test for the prepolymerized denture acrylic resin specimen groups, and 1-way ANOVA and the Tukey test for the zirconia groups at α = 0.05. RESULTS: Mean and standard deviation retention force values varied from 101.1 ± 67.1 to 509.0 ± 65.2 N for the prepolymerized denture acrylic resin specimen groups. The zirconia groups ranged from 572.8 ± 274.7 to 1416.1 ± 258.0 N. There is no statistically significant difference in retention force values between V and C specimens cementing to zirconia with Panavia SA cement (Kuraray Noritake) (p = 0.587). The retention forces and failure modes were influenced by the cement used (p < 0.05). Modes of failure were predominantly Type 2 (mixed failure) and Type 1 (adhesive fracture from prosthetic materials) except for the quick-set resin group (Type 3, adhesive failure from coping). CONCLUSIONS: When bonding IFDPs onto titanium copings, quick-set resin provided significantly higher retention force for prepolymerized denture acrylic resin prostheses. Conical and cylindrical titanium copings performed similarly when cemented to zirconia with Panavia SA cement under the same protocol. The stability of the bonded interface and retention forces between zirconia prostheses and titanium copings varied from the cement used.


Assuntos
Silicatos de Alumínio , Implantes Dentários , Titânio , Cimentos Dentários , Cimentos de Resina , Zircônio , Cimentos de Ionômeros de Vidro , Resinas Acrílicas , Adaptação Psicológica , Teste de Materiais , Análise do Estresse Dentário , Retenção em Prótese Dentária , Propriedades de Superfície
7.
Medicine (Baltimore) ; 102(32): e34672, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37565874

RESUMO

BACKGROUND: Propranolol is the first choice for treating infantile hemangioma (IH). How propranolol works in IH remains unclear. Infantile hemangioma endothelial cells (HemECs) express Notch1, Jagged, Hey1, and other molecules in the Notch pathway, suggesting that Notch pathway-related molecules play an important role in affecting vascular endothelial cell proliferation. Whether propranolol can affect the Notch signaling pathway in IH treatment is unclear. METHODS: We performed this study to observe the effect of propranolol on the expression of Notch signaling pathway molecules in human umbilical vein endothelial cells (HUVECs) and to explore the therapeutic mechanism of propranolol on IH. HUVECs cultured in vitro were exposed to 60, 120, 240, 360, or 480 µM propranolol. The morphological changes of the HUVECs were observed under an inverted microscope. HUVECs proliferation was detected with Cell Counting Kit-8 (CCK-8). The effects of propranolol on HUVECs apoptosis were detected by flow cytometry. The role of Notch in propranolol inhibition of HUVEC proliferation was analyzed with real-time polymerase chain reaction (PCR) and western blotting. RESULTS: Propranolol reduced HUVECs numbers and altered their morphology. The inhibitory effect of propranolol on cell proliferation was dependent on the reaction time and drug concentration. Propranolol upregulated Jagged1, Notch1, and Hey1 expression and downregulated delta-like ligand4 (DLL4) expression. CONCLUSIONS: Propranolol may play a role in IH treatment by increasing Jagged1 expression in endothelial cells, activating the Notch pathway and inducing the upregulation of the downstream target gene HEY1.


Assuntos
Hemangioma , Propranolol , Humanos , Células Endoteliais da Veia Umbilical Humana , Propranolol/farmacologia , Propranolol/uso terapêutico , Transdução de Sinais/genética , Hemangioma/tratamento farmacológico , Hemangioma/genética , Biologia , Proliferação de Células
8.
J Neurol Neurosurg Psychiatry ; 94(8): 605-613, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37225405

RESUMO

To explore the autoimmune response and outcome in the central nervous system (CNS) at the onset of viral infection and correlation between autoantibodies and viruses. METHODS: A retrospective observational study was conducted in 121 patients (2016-2021) with a CNS viral infection confirmed via cerebrospinal fluid (CSF) next-generation sequencing (cohort A). Their clinical information was analysed and CSF samples were screened for autoantibodies against monkey cerebellum by tissue-based assay. In situ hybridisation was used to detect Epstein-Barr virus (EBV) in brain tissue of 8 patients with glial fibrillar acidic protein (GFAP)-IgG and nasopharyngeal carcinoma tissue of 2 patients with GFAP-IgG as control (cohort B). RESULTS: Among cohort A (male:female=79:42; median age: 42 (14-78) years old), 61 (50.4%) participants had detectable autoantibodies in CSF. Compared with other viruses, EBV increased the odds of having GFAP-IgG (OR 18.22, 95% CI 6.54 to 50.77, p<0.001). In cohort B, EBV was found in the brain tissue from two of eight (25.0%) patients with GFAP-IgG. Autoantibody-positive patients had a higher CSF protein level (median: 1126.00 (281.00-5352.00) vs 700.00 (76.70-2899.00), p<0.001), lower CSF chloride level (mean: 119.80±6.24 vs 122.84±5.26, p=0.005), lower ratios of CSF-glucose/serum-glucose (median: 0.50[0.13-0.94] vs 0.60[0.26-1.23], p=0.003), more meningitis (26/61 (42.6%) vs 12/60 (20.0%), p=0.007) and higher follow-up modified Rankin Scale scores (1 (0-6) vs 0 (0-3), p=0.037) compared with antibody-negative patients. A Kaplan-Meier analysis revealed that autoantibody-positive patients experienced significantly worse outcomes (p=0.031). CONCLUSIONS: Autoimmune responses are found at the onset of viral encephalitis. EBV in the CNS increases the risk for autoimmunity to GFAP.


Assuntos
Encefalite , Infecções por Vírus Epstein-Barr , Masculino , Humanos , Feminino , Autoimunidade , Estudos Retrospectivos , Herpesvirus Humano 4 , Autoanticorpos , Imunoglobulina G
9.
J Am Chem Soc ; 145(8): 4473-4484, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36794997

RESUMO

Many amyloid fibrils associated with neurodegenerative diseases consist of an ordered fibril core (FC) and disordered terminal regions (TRs). The former represents a stable scaffold, while the latter is rather active in binding with various partners. Current structural studies mainly focus on the ordered FC since the high flexibility of TRs hinders structural characterization. Here, by combining insensitive nuclei enhanced by polarization transfer-based 1H-detected solid-state NMR and cryo-EM, we explored the intact structure of an α-syn fibril including both FC and TRs and further studied the conformational dynamics of the fibril upon binding to lymphocyte activation gene 3 (LAG3)─a cell surface receptor that is involved in α-syn fibril transmission in brains. We found that both the N- and C-TRs of α-syn are disordered in free fibrils featuring similar conformation ensembles as those in soluble monomers. While in the presence of the D1 domain of LAG3 (L3D1), the C-TR directly binds to L3D1, meanwhile the N-TR folds into a ß-strand and further integrates with the FC, which leads to alteration of the overall fibril structure and surface property. Our work reveals synergistic conformational transition of the intrinsically disordered TRs of α-syn, which sheds light on mechanistic understanding of the essential role of TRs in regulating the structure and pathology of amyloid fibrils.


Assuntos
Amiloide , alfa-Sinucleína , alfa-Sinucleína/química , Microscopia Crioeletrônica , Espectroscopia de Ressonância Magnética , Conformação Molecular , Amiloide/química
10.
Int J Neurosci ; 133(7): 701-704, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34387528

RESUMO

Purpose: The co-infection with Orientia tsutsugamushand and hemorrhagic fever with renal syndrome is rare. There are many similarities in early clinical practice between the two diseases, and sometimes it is easy to misdiagnose, especially when co-infection occurs.Methods: We describe a patient who presented with fever and headache after bitten by an insect and whose physical examination showed conjunctival hyperemia, eschar and petechiae in tongue and the soft palate. To lead to a diagnosis, the serum antibody of Hantaan virus, Weil-Felix test and  next-generation sequencing of cerebrospinal fluid was performed.Results: The Weil-Felix test was negative on the 15th day after the onset of the disease and a repeated Weil-Felix test on the 21st day showed a titer of 1:160 and the IgM against Hantaan virus was positive. The number of sequence reads identified corresponding to O. tsutsugamushi was 239 with a genomic coverage of 0.9178%. This patient was diagnosed with intracranial infection with Orientia tsutsugamushi and co-infection with epidemic hemorrhagic fever. The symptoms in our patient quickly decreased after the administration of tetracycline.Conclusion: Next-generation sequencing is helpful for the early diagnosis of scrub typhus, especially when the Weil-Felix test is negative. Clinicians need to be reminded to screen for common pathogens that may be co-infected, such as epidemic hemorrhagic fever.


Assuntos
Coinfecção , Febre Hemorrágica com Síndrome Renal , Tifo por Ácaros , Humanos , Febre Hemorrágica com Síndrome Renal/complicações , Febre Hemorrágica com Síndrome Renal/diagnóstico , Coinfecção/diagnóstico , Orientia , Tifo por Ácaros/complicações , Tifo por Ácaros/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala
11.
J Prosthodont ; 32(2): 139-146, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35315177

RESUMO

PURPOSE: The aim of this in vitro study was to assess the efficacy of fiber reinforcement to enhance flexural strength of the transitional implant-supported fixed dental prosthesis (TISFDP). MATERIALS AND METHODS: One hundred and forty denture acrylic resin plates (64 mm × 12 mm × 5 mm) with two 7 mm diameter holes were fabricated using heat-polymerized type (Lucitone 199) and CAD-CAM prepolymerized type (AvaDent) materials to simulate a chair-side reconstruction of the TISFDP. Specimens were divided into 7 groups (n = 10) according to the airborne-particle abrasion of titanium cylinder (Straumann) surface and locations of fiber reinforcement ribbons (Ribbond-ULTRA). No cylinder surface abrasion and no fiber added acrylate specimens were used as the controls. The prosthetic screws were hand-tightened on a custom fixture with analogs. Specimen hole and cylinder were joined using a 50:50 mixture of chemically polymerized resin (QYK-SET; Holmes Dental) and repair resin (Dentsply Sirona). Ten acrylate specimens with no holes were fabricated from each tested material and assigned as positive controls. A modified four-point bending test (ASTM standard-D6272) was conducted using a universal testing machine and a custom fixture with a crosshead speed 1 mm/min. The maximum failure loads were recorded. Data were statistically analyzed using 2-way ANOVA and the Tukey tests at α = 0.05. RESULTS: The flexural strength values ranged from 55.4 ±8.3 to 140.9 ±15.4 MPa. The flexural strength decreased significantly when fiber was attached on the titanium cylinder surface (p < 0.05). There were no statistically significant differences in flexural strength values between specimens with and without titanium cylinder surface abrasion (p > 0.05). Statistically significant improvement in flexural strength was observed in specimens with fibers attached around the specimen holes (p < 0.05) buccally and lingually. The obtained values were not statistically significantly different from the positive controls (p > 0.05). Some fixation screw fractures were observed before catastrophic failure of specimens during testing. CONCLUSIONS: Fiber reinforcement significantly improved the flexural strength of denture acrylic resins only if placed around the specimen holes on the tension side at the site of initiation of crack propagation. Even when the specimens underwent catastrophic failure, the segments remained attached to each other with the attached fibers.


Assuntos
Implantes Dentários , Resistência à Flexão , Titânio , Teste de Materiais , Maleabilidade , Propriedades de Superfície , Acrilatos , Análise do Estresse Dentário , Bases de Dentadura , Materiais Dentários
12.
J Prosthet Dent ; 130(6): 866-876, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35153064

RESUMO

STATEMENT OF PROBLEM: A novel zirconia-alumina composite (ZAC) particle has yet to be studied for airborne-particle abrasion in a bonding protocol for the zirconia surface. PURPOSE: The purpose of this in vitro study was to evaluate the shear bond force of resin cement to yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) when using spherical ZAC particles to conduct airborne-particle abrasion and modify the topography of Y-TZP. MATERIAL AND METHODS: Spherical 30- to 70-µm ZAC particles were fabricated by using a hybrid gel technique. A total of 160 Ø6.6×4.0-mm zirconia disks were fabricated from 4 commercially available zirconia blanks, e.max ZirCAD zirconia (EM), NexxZr T zirconia (NE), Lava Plus High Translucency zirconia (LP), and Imagine High Translucency Zirconia (IM), by using computer-aided manufacturing technology. As-sintered specimens without further surface treatment were used as controls (ZR0). Surface treatment groups included sharp-edged alumina airborne-particle abrasion (ABC), 50 µm, 0.2 MPa; airborne-particle abrasion with ZAC particle at 0.2 MPa (2ZA); and airborne-particle abrasion with spherical ZAC particle at 0.4 MPa (4ZA). All surface treatment groups were airborne-particle abraded at the specified pressures for 10 seconds at a standardized distance of 10 mm. The surface roughness (Ra) and area roughness (Sa) of specimens from each group were measured. Following the application of an adhesive (Scotchbond Universal), Ø6.6×4.0-mm resin cement (RelyX Ultimate) buttons were fabricated for shear bond testing by using a universal testing machine at a 5-mm/min crosshead speed (n=10). The data were analyzed by using a 2-way ANOVA, Tukey HSD test, and regression analysis (α=0.05). Scanning electron microscopy (SEM) was performed to observe changes of the zirconia surface and the failure modes of each group before and after shear bond testing. RESULTS: The mean ±standard deviation shear bond force values ranged from 272.6 ±41.4 N to 686.7 ±152.8 N. Statistically significant higher force values than those of the controls (P<.05) were obtained by using airborne-particle abrasion. No significant differences were found among any of the airborne-particle abrasion treatment groups (P>.05). The mean of Ra values ranged from 0.27 µm to 0.74 µm, and the mean of Sa values, from 0.48 µm to 1.48 µm. SEM observation revealed that the zirconia surface was made jagged by abrasion with sharp-edged alumina particles. The spherical ZAC particles create microcraters on the zirconia surface. Fractographic observation disclosed that failures were adhesive-cohesive failure modes with residual resin cement attached on the zirconia surface. CONCLUSIONS: The surface treatment of zirconia with sharp-edged alumina or the spherical ZAC abrasives improved the bonding force between the zirconia and resin cement. No statistically significant differences in shear bond force values were found between airborne-particle abrasion surface treatment groups.


Assuntos
Colagem Dentária , Materiais Dentários , Materiais Dentários/química , Cimentos de Resina/química , Propriedades de Superfície , Cerâmica/química , Zircônio/química , Óxido de Alumínio/química , Teste de Materiais , Resistência ao Cisalhamento , Análise do Estresse Dentário
13.
J Mol Biol ; 435(1): 167680, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35690099

RESUMO

Amyloid aggregation of α-synuclein (α-syn) in Lewy bodies (LBs) is the pathological hallmark of Parkinson's disease (PD). Iron, especially Fe3+, is accumulated in substantia nigra of PD patients and co-deposited with α-syn in LBs. However, how Fe3+ modulates α-syn fibrillation at molecular level remains unclear. In this study, we found that Fe3+ can promote α-syn fibrillation at low concentration while inhibit its fibrillation at high concentration. NMR titration study shows poor interaction between α-syn monomer and Fe3+. Instead, we found that Fe3+ binds to α-syn fibrils. By using cryo-electron microscopy (cryo-EM), we further determined the atomic structure of α-syn fibril in complex with Fe3+ at the resolution of 2.7 Å. Strikingly, two extra electron densities adjacent to His50 and Glu57 were observed as putative binding sites of Fe3+ and water molecules, suggesting that Fe3+ binds to the negative cleft of the fibril and stabilizes the fibril structure for promoting α-syn aggregation. Further mutagenesis study shows mutation of His50 abolishes the Fe3+-facilitated fibrillation of α-syn. Our work illuminates the structural basis of the interaction of Fe3+ and α-syn in both monomeric and fibrillar forms, and sheds light on understanding the pathological role of Fe3+ in α-syn aggregation in PD.


Assuntos
Amiloide , Doença de Parkinson , Agregação Patológica de Proteínas , alfa-Sinucleína , Humanos , alfa-Sinucleína/química , alfa-Sinucleína/genética , Amiloide/química , Microscopia Crioeletrônica , Mutação , Doença de Parkinson/metabolismo , Agregação Patológica de Proteínas/metabolismo , Ferro/química
14.
Med Mol Morphol ; 56(1): 78-83, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35851413

RESUMO

Juvenile polyposis syndrome (JPS) is a rare autosomal dominant inherited disease characterised by multiple juvenile polyps. Genes with JPS-associated mutations and their correlation with the phenotype are currently unknown. Gastrointestinal endoscopy results of a 31-year-old female patient showed multiple polyps in the digestive tract, and the presence of juvenile polyps was confirmed by pathological examination. During follow-up, the patient underwent total gastrectomy and polypectomy several times. Five members of this family were diagnosed with JPS, of which two died and three survived. Full exon gene sequencing of eight members of this family revealed a SMAD4 (NM-005359.3) c.1035C > A (p.Cys345*) mutation. This mutation leads to premature codon termination, causing protein truncation. SMAD4 is a pathogenic gene associated with JPS. This is the first report of an association between the c.1035C > A mutation and JPS pathogenesis. Detection of JPS-related mutations in family members with a genetic predisposition for JPS is very important for genetic counselling, surgical intervention, long-term monitoring and follow-up, and drug treatment.


Assuntos
Polipose Intestinal , Síndromes Neoplásicas Hereditárias , Feminino , Humanos , Sequenciamento do Exoma , Polipose Intestinal/genética , Síndromes Neoplásicas Hereditárias/genética , Células Germinativas , Proteína Smad4/genética
15.
Recent Pat Anticancer Drug Discov ; 18(4): 506-516, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36464873

RESUMO

BACKGROUND: The occurrence and progression of cancer are the results of the dysregulation of genetics and epigenetics. Epigenetic regulation can reversibly affect gene transcription activity without changing DNA structure. Covalent modification of histones is crucial in the epigenetic regulation of gene expression. Furthermore, epidermal growth factor receptor (EGFR) significantly affects cell tumorigenesis, proliferation, antitumor drug resistance, etc. Overexpression of EGFR promotes cancer development. Therefore, EGFR-targeted drugs have become the focus of tumor therapy. With the advent of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), EGFR-TKIs resistance, which occurs about half a year to a year, has become an obstacle in cancer treatment. OBJECTIVE: The objective of this study is to discuss the ways to overcome EGFR-TKIs resistance in a variety of tumors. METHODS: The combination therapy of epigenetic drugs and other drugs is used. RESULTS: The combination of the two drugs can overcome the resistance of EGFR-TKIs and prolong the survival of patients. CONCLUSION: This article depicts the concepts of epigenetics and the mechanism of EGFR-TKIs resistance and then illustrates the relationship between epigenetic mechanisms and EGFR-TKIs resistance. Finally, it discusses the clinical research and the latest patents for using epigenetic drugs to reverse EGFR-TKIs resistance in human cancer. In the future, more novel targets may be discovered for overcoming resistance to EGFR-TKIs, not just on histone deacetylases (HDACs). The dosing course and mode of administration of the combination therapy containing epigenetic drugs need further study. This review provides new ideas for using epigenetic agents to overcome EGFR-TKIs resistance.


Assuntos
Antineoplásicos , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Epigênese Genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Patentes como Assunto , Receptores ErbB/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Mutação
19.
PLoS One ; 17(11): e0275312, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36383540

RESUMO

Interest in sustainable food consumption has gradually increased over the previous third decades. Despite substantial studies addressing various topics connected to sustainable food consumption, little research systematically evaluates which factors influence consumers' purchase of sustainable food. We aim to integrate preliminary findings, compare four original and extended models of the theory of planned behavior (TPB) in the context of sustainable food consumption, and identify measurement and situational moderators using a meta-analytic structural equation modeling approach. The results show that attitude (ATT), subjective norms (SN), and perceived behavioral control (PBC) were most strongly positively correlated with a purchase intention (PI) of sustainable food. Furthermore, the analysis of the moderating effects revealed significant differences in the relationship between PBC and purchase behavior (PB) and between SN and PI in developing and developed countries. In addition, by comparing four original and extended TPB models, this study proposes a theoretical framework to affect customers' PI of sustainable food. The findings of this study can be used as a foundation for company marketing and government environmental protection promotion.


Assuntos
Intenção , Teoria Psicológica , Inquéritos e Questionários , Atitude , Preferências Alimentares , Comportamento do Consumidor
20.
Front Pharmacol ; 13: 1040847, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386204

RESUMO

Background: Intrahepatic Cholangiocarcinoma (iCCA) is a highly malignant tumor with limited treatment options that contributes largely to cancer-related deaths worldwide. Compared with traditional transcriptomic analysis, single-cell RNA sequencing (scRNA-seq) is emerging as a more advanced and popular tool for the in-depth exploration of cellular diversity and molecular complexity. As a next-generation proteasome inhibitor, MLN2238 presents better pharmacodynamics, pharmacokinetics, and therapeutic responses in various cancers. However, its effects and mechanisms of action in iCCA remain unknown. Methods: iCCA tumor heterogeneity was determined based on 4,239 qualified scRNA-seq data from 10 iCCA samples. The potential biological roles of proteasome-related genes in iCCA were investigated using a pseudo-trajectory reconstruction. The effect of MLN2238 on iCCA cell proliferation was estimated using the CCK-8, EdU, and clone formation assays. Flow cytometry was used to examine the effect of added MLN2238 on cell cycle and apoptosis levels. Autophagic flux was detected using AdPlus-mCherry-GFP-LC3B cells. ROS levels and mitochondrial membrane potential were determined using DCFH-DA probing and JC-1 staining. JNK activation and mitochondrial apoptosis were observed using western blotting and immunofluorescence microscopy, respectively. Finally, we used a tumor-bearing mouse model to validate its efficacy in vivo for iCCA treatment. Results: Proteasome-related genes were dysregulated in iCCA progression and expressed at higher levels in tumor tissues. MLN2238 suppressed cell proliferation, blocked the cell cycle in the G2/M phase, promoted apoptosis, and induced cytoprotective autophagy in iCCA cells. Furthermore, MLN2238 increased ROS levels and activated the JNK signaling pathway. Inhibition of ROS and JNK activation by NAC and SP600125 significantly reversed MLN2238-induced apoptosis. MLN2238 also suppressed the growth of iCCA tumors in vivo. Conclusion: Proteasome-related genes play pivotal roles in iCCA development. MLN2238, as a proteasome inhibitor, induces apoptosis in iCCA cells through ROS/JNK/mitochondrial signaling pathways, and hence, making MLN2238 a potential therapeutic choice for iCCA.

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