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1.
Transl Neurodegener ; 13(1): 39, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095921

RESUMO

BACKGROUND: Deoxyribonuclease 2 (DNase II) plays a key role in clearing cytoplasmic double-stranded DNA (dsDNA). Deficiency of DNase II leads to DNA accumulation in the cytoplasm. Persistent dsDNA in neurons is an early pathological hallmark of senescence and neurodegenerative diseases including Alzheimer's disease (AD). However, it is not clear how DNase II and neuronal cytoplasmic dsDNA influence neuropathogenesis. Tau hyperphosphorylation is a key factor for the pathogenesis of AD. The effect of DNase II and neuronal cytoplasmic dsDNA on neuronal tau hyperphosphorylation remains unclarified. METHODS: The levels of neuronal DNase II and dsDNA in WT and Tau-P301S mice of different ages were measured by immunohistochemistry and immunolabeling, and the levels of DNase II in the plasma of AD patients were measured by ELISA. To investigate the impact of DNase II on tauopathy, the levels of phosphorylated tau, phosphokinase, phosphatase, synaptic proteins, gliosis and proinflammatory cytokines in the brains of neuronal DNase II-deficient WT mice, neuronal DNase II-deficient Tau-P301S mice and neuronal DNase II-overexpressing Tau-P301S mice were evaluated by immunolabeling, immunoblotting or ELISA. Cognitive performance was determined using the Morris water maze test, Y-maze test, novel object recognition test and open field test. RESULTS: The levels of DNase II were significantly decreased in the brains and the plasma of AD patients. DNase II also decreased age-dependently in the neurons of WT and Tau-P301S mice, along with increased dsDNA accumulation in the cytoplasm. The DNA accumulation induced by neuronal DNase II deficiency drove tau phosphorylation by upregulating cyclin-dependent-like kinase-5 (CDK5) and calcium/calmodulin activated protein kinase II (CaMKII) and downregulating phosphatase protein phosphatase 2A (PP2A). Moreover, DNase II knockdown induced and significantly exacerbated neuron loss, neuroinflammation and cognitive deficits in WT and Tau-P301S mice, respectively, while overexpression of neuronal DNase II exhibited therapeutic benefits. CONCLUSIONS: DNase II deficiency and cytoplasmic dsDNA accumulation can initiate tau phosphorylation, suggesting DNase II as a potential therapeutic target for tau-associated disorders.


Assuntos
Doença de Alzheimer , Endodesoxirribonucleases , Neurônios , Proteínas tau , Animais , Proteínas tau/metabolismo , Proteínas tau/genética , Fosforilação , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Doença de Alzheimer/patologia , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/deficiência , Endodesoxirribonucleases/metabolismo , Camundongos Transgênicos , DNA/genética , Masculino , Feminino , Encéfalo/metabolismo , Encéfalo/patologia , Camundongos Endogâmicos C57BL
2.
Zhonghua Nan Ke Xue ; 30(4): 315-320, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-39210417

RESUMO

OBJECTIVE: To retrospectively analyze the causes of missed diagnosis of clinically significant PCa (csPCa) by targeted biopsy (TB). METHODS: This retrospective study included 652 males aged (71.32 ± 16.53) years with elevated PSA and abnormal MRI signals detected in our hospital from June 2018 to December 2020. We further examined the patients by transperineal prostatic TB and systematic biopsy (SB), analyzed the detection rates of PCa and csPCa by TB and SB, and investigated the causes of missed diagnosis of csPCa in TB using the fishbone diagram. RESULTS: The total detection rate of PCa and csPCa by TB combined with SB was 45.7% (298/652), and that of csPCa was 37.4% (244/652), with 38 cases of csPCa missed in TB, including 23 cases of negative TB and 15 cases of low ISUP grade. The causes of missed diagnosis of csPCa by TB included low MRI image quality, PSA density ≤0.15 ng/ml/cm3, target area <10 mm, and PI-RADS 2 score ≤3. The detection rate of csPCa by TB alone was 31.6%, which was increased by 5.8% (P = 0.027) when TB combined with SB. CONCLUSION: TB combined with SB yields a higher detection rate of csPCa than either used alone. Missed diagnosis of csPCa by TB is closely related to the characteristics of tumor and MR image of the target area.


Assuntos
Imageamento por Ressonância Magnética , Diagnóstico Ausente , Neoplasias da Próstata , Humanos , Masculino , Idoso , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Próstata/patologia , Próstata/diagnóstico por imagem , Antígeno Prostático Específico/sangue , Biópsia Guiada por Imagem/métodos , Idoso de 80 Anos ou mais
3.
Zhongguo Zhong Yao Za Zhi ; 49(14): 3878-3886, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39099361

RESUMO

To investigate the mechanism by which Peitu Yifei Granules inhibit idiopathic pulmonary fibrosis(IPF) in rats, fifty specific-pathogen-free(SPF) grade male Wistar rats were randomly divided into blank group and modeling group. IPF was induced in the modeling group rats by tracheal infusion of 5 mg·kg~(-1) bleomycin(BLM) and then randomly divided into model group, pirfenidone group, and high-dose, medium-dose, and low-dose groups treated with Peitu Yifei Granules. After 24 hours of modeling, the treatment groups received intragastric administration of either Peitu Yifei Granules or pirfenidone as a positive control drug; meanwhile, the model group received an equal volume of normal saline. After 21 days of treatment administration, lung tissue samples were collected for analysis. Pathological changes in lung tissues were assessed using hematoxylin-eosin(HE) staining and Masson's trichrome staining. The expression levels of protein kinase B(Akt), mammalian target of rapamycin(mTOR), their phosphorylated forms, and sequestosome 1(p62) were determined through Western blot(WB). Fluorescent quantitative real-time polymerase chain reaction(RT-qPCR) was used to measure messenger ribonucleic acid(mRNA) expression levels of Beclin-1, microtubule-associated proteins 1A/1B light chain 3B(LC3B), and p62. Immunohistochemistry was performed to assess protein expression levels of Beclin-1 and LC3B in lung tissue samples. RESULTS:: demonstrated that lung tissue structure appeared normal without significant collagen deposition in the blank group rats. In contrast, rats from the model group exhibited thickened alveolar septa along with evident inflammatory changes and collagen deposition. Compared to the model group rats, those treated with Peitu Yifei Granules or pirfenidone showed significantly improved lung tissue structure with reduced inflammation and collagen deposition observed histologically. Furthermore, compared with those of the blank group, the expressions of p62 and its mRNA, p-Akt and p-mTOR protein in lung tissues of the model group were significantly increased, while Beclin-1, LC3B and their mRNA levels were significantly decreased. Compared with those of the model group, the expressions of p62 and its mRNA, p-Akt and p-mTOR in lung tissues of the pirfenidone group and Peitu Yifei Granules high-dose and medium-dose groups were significantly decreased, while Beclin-1, LC3B and their mRNA expressions were significantly increased. The above results indicate that Peitu Yifei Granules can improve autophagy levels in lung tissues by inhibiting the phosphoinositide 3-kinase(PI3K)/Akt/mTOR signaling pathway and delay the development of IPF disease.


Assuntos
Autofagia , Medicamentos de Ervas Chinesas , Fibrose Pulmonar Idiopática , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Ratos Wistar , Transdução de Sinais , Serina-Treonina Quinases TOR , Animais , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Masculino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Autofagia/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Humanos
4.
World J Gastrointest Oncol ; 16(6): 2842-2861, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38994129

RESUMO

BACKGROUND: Gastrointestinal neoplasm (GN) significantly impact the global cancer burden and mortality, necessitating early detection and treatment. Understanding the evolution and current state of research in this field is vital. AIM: To conducts a comprehensive bibliometric analysis of publications from 1984 to 2022 to elucidate the trends and hotspots in the GN risk assessment research, focusing on key contributors, institutions, and thematic evolution. METHODS: This study conducted a bibliometric analysis of data from the Web of Science Core Collection database using the "bibliometrix" R package, VOSviewer, and CiteSpace. The analysis focused on the distribution of publications, contributions by institutions and countries, and trends in keywords. The methods included data synthesis, network analysis, and visualization of international collaboration networks. RESULTS: This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and collaboration. It highlights the United States' critical role in advancing this field, with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer Institute. The last five years, substantial advancements have been made, representing nearly 45% of the examined literature. Publication rates have dramatically increased, from 20 articles in 2002 to 112 in 2022, reflecting intensified research efforts. This study underscores a growing trend toward interdisciplinary and international collaboration, with the Journal of Clinical Oncology standing out as a key publication outlet. This shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN risks. CONCLUSION: This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research emphasis. This calls for enhanced global collaboration and integration of artificial intelligence to improve cancer prevention and treatment accuracy, ultimately enhancing worldwide patient care.

5.
World J Clin Cases ; 12(20): 4427-4433, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39015910

RESUMO

BACKGROUND: Benign recurrent intrahepatic cholestasis (BRIC) is a rare autosomal recessive disorder, characterized by episodes of intense pruritus, elevated serum levels of alkaline phosphatase and bilirubin, and near-normal -glutamyl transferase. These episodes may persist for weeks to months before spontaneously resolving, with patients typically remaining asymptomatic between occurrences. Diagnosis entails the evaluation of clinical symptoms and targeted genetic testing. Although BRIC is recognized as a benign genetic disorder, the triggers, particularly psychosocial factors, remain poorly understood. CASE SUMMARY: An 18-year-old Chinese man presented with recurrent jaundice and pruritus after a cold, which was exacerbated by self-medication involving vitamin B and paracetamol. Clinical and laboratory evaluations revealed elevated levels of bilirubin and liver enzymes, in the absence of viral or autoimmune liver disease. Imaging excluded biliary and pancreatic abnormalities, and liver biopsy demonstrated centrilobular cholestasis, culminating in a BRIC diagnosis confirmed by the identification of a novel ATP8B1 gene mutation. Psychological assessment of the patient unveiled stress attributable to academic and familial pressures, regarded as potential triggers for BRIC. Initial relief was observed with ursodeoxycholic acid and cetirizine, followed by an adjustment of the treatment regimen in response to elevated liver enzymes. The patient's condition significantly improved following a stress-related episode, thanks to a comprehensive management approach that included psychosocial support and medical treatment. CONCLUSION: Our research highlights genetic and psychosocial influences on BRIC, emphasizing integrated diagnostic and management strategies.

6.
J Am Heart Assoc ; 13(14): e035337, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38979802

RESUMO

BACKGROUND: Statins are widely used for treating patients with ischemic stroke at risk of secondary cerebrovascular events. It is unknown whether Asian populations benefit from more intensive statin-based therapy for stroke recurrence. Therefore, in the present study we evaluated the effectiveness and safety of high-dose and moderate-dose statins for patients who had experienced mild ischemic stroke during the acute period. METHODS AND RESULTS: This multicenter prospective study included patients with mild ischemic stroke who presented within 72 hours of symptom onset. The outcomes of patients in the high-intensity and moderate-intensity statin treatment groups were compared, with the main efficacy outcome being stroke recurrence and the primary safety end point being intracranial hemorrhage. The propensity score matching method was employed to control for imbalances in baseline variables. Subgroup analyses were conducted to evaluate group differences. In total, the data of 2950 patients were analyzed at 3 months, and the data of 2764 patients were analyzed at 12 months due to loss to follow-up. According to the multivariable Cox analyses adjusted for potential confounders, stroke recurrence occurred similarly in the high-intensity statin and moderate-intensity statin groups (3 months: adjusted hazard ratio [HR], 1.12 [95% CI, 0.85-1.49]; P=0.424; 12 months: adjusted HR, 1.08 [95% CI, 0.86-1.34]; P=0.519). High-intensity statin therapy was associated with an increased risk of intracranial hemorrhage (3 months: adjusted HR, 1.81 [95% CI, 1.00-3.25]; P=0.048; 12 months: adjusted HR, 1.86 [95% CI, 1.10-3.16]; P=0.021). The results from the propensity score-matched analyses were consistent with those from the Cox proportional hazards analysis. CONCLUSIONS: Compared with moderate-intensity statin therapy, high-dose statin therapy may not decrease the risk of mild, noncardiogenic ischemic stroke recurrence but may increase the risk of intracranial hemorrhage. REGISTRATION: URL: www.chictr.org.cn/. Unique Identifier: ChiCTR1900025214.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , AVC Isquêmico , Recidiva , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Feminino , Masculino , Estudos Prospectivos , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/epidemiologia , AVC Isquêmico/diagnóstico , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Fatores de Tempo , Fatores de Risco , Pontuação de Propensão , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/epidemiologia , Índice de Gravidade de Doença , Prevenção Secundária/métodos
7.
Fish Shellfish Immunol ; 152: 109775, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39019126

RESUMO

Bacterial intestinal inflammation frequently occurs in cultured fish. Nevertheless, research on intestinal barrier dysfunction in the process of intestinal inflammation is deficient. In this study, we explored the changes of intestinal inflammation induced by Aeromonas hydrophila (A. hydrophila) in snakehead and the relationship between intestinal barrier and inflammation. Snakehead [(13.05 ± 2.39) g] were infected via anus with A. hydrophila. Specimens were collected for analysis at 0, 1, 3, 7 and 21 d post-injection. The results showed that with the increase of exposure time, the hindgut underwent stages of normal function, damage, damage deterioration, repair and recovery. Relative to 0 d, the levels of IL-1ß and TNF-α in serum, and the expression of nod1, tlr1, tlr5, nf-κb, tnf-α and il-1ß in intestine were significantly increased, and showed an upward then downward pattern over time. However, the expression of tlr2 and il-10 were markedly decreased, and showed the opposite trend. In addition, with the development of intestinal inflammation, the diversity and richness of species, and the levels of phylum and genus in intestine were obviously altered. The levels of trypsin, LPS, AMS, T-SOD, CAT, GPx, AKP, LZM and C3 in intestine were markedly reduced, and displayed a trend of first decreasing and then rebounding. The ultrastructure observation showed that the microvilli and tight junction structure of intestinal epithelial cells experienced normal function initially, then damage, and finally recovery over time. The expression of claudin-3 and zo-1 in intestine were significantly decreased, and showed a trend of first decreasing and then rebounding. Conversely, the expression of mhc-i, igm, igt and pigr in intestine were markedly increased, and displayed a trend of increasing first and then decreasing. The above results revealed the changes in intestinal barrier during the occurrence and development of intestinal inflammation, which provided a theoretical basis for explaining the relationship between the two.


Assuntos
Aeromonas hydrophila , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Intestinos , Animais , Aeromonas hydrophila/fisiologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Peixes/imunologia , Peixes/microbiologia , Microbioma Gastrointestinal , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Inflamação/imunologia , Inflamação/veterinária , Mucosa Intestinal/imunologia , Intestinos/imunologia , Intestinos/patologia
8.
World J Gastroenterol ; 30(21): 2777-2792, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38899329

RESUMO

BACKGROUND: Obesity is associated with a significantly increased risk for chronic diarrhea, which has been proposed as Linghu's obesity-diarrhea syndrome (ODS); however, its molecular mechanisms are largely unknown. AIM: To reveal the transcriptomic changes in the jejunum involved in ODS. METHODS: In a cohort of 6 ODS patients (JOD group), 6 obese people without diarrhea (JO group), and 6 healthy controls (JC group), high-throughput sequencing and bioinformatics analyses were performed to identify jejunal mucosal mRNA expression alterations and dysfunctional biological processes. In another cohort of 16 ODS patients (SOD group), 16 obese people without diarrhea (SO group), and 16 healthy controls (SC group), serum diamine oxidase (DAO) and D-lactate (D-LA) concentrations were detected to assess changes in intestinal barrier function. RESULTS: The gene expression profiles of jejunal mucosa in the JO and JC groups were similar, with only 1 differentially expressed gene (DEG). The gene expression profile of the JOD group was significantly changed, with 411 DEGs compared with the JO group and 211 DEGs compared with the JC group, 129 of which overlapped. The enrichment analysis of these DEGs showed that the biological processes such as digestion, absorption, and transport of nutrients (especially lipids) tended to be up-regulated in the JOD group, while the biological processes such as rRNA processing, mitochondrial translation, antimicrobial humoral response, DNA replication, and DNA repair tended to be down-regulated in the JOD group. Eight DEGs (CDT1, NHP2, EXOSC5, EPN3, NME1, REG3A, PLA2G2A, and PRSS2) may play a key regulatory role in the pathological process of ODS, and their expression levels were significantly decreased in ODS patients (P < 0.001). In the second cohort, compared with healthy controls, the levels of serum intestinal barrier function markers (DAO and D-LA) were significantly increased in all obese individuals (P < 0.01), but were higher in the SOD group than in the SO group (P < 0.001). CONCLUSION: Compared with healthy controls and obese individuals without diarrhea, patients with Linghu's ODS had extensive transcriptomic changes in the jejunal mucosa, likely affecting intestinal barrier function and thus contributing to the obesity and chronic diarrhea phenotypes.


Assuntos
Diarreia , Perfilação da Expressão Gênica , Mucosa Intestinal , Jejuno , Obesidade , Transcriptoma , Humanos , Jejuno/metabolismo , Masculino , Projetos Piloto , Feminino , Diarreia/genética , Diarreia/etiologia , Diarreia/metabolismo , Adulto , Mucosa Intestinal/metabolismo , Obesidade/genética , Obesidade/complicações , Pessoa de Meia-Idade , Perfilação da Expressão Gênica/métodos , Estudos de Casos e Controles , Síndrome , Amina Oxidase (contendo Cobre)/genética , Amina Oxidase (contendo Cobre)/sangue , Amina Oxidase (contendo Cobre)/metabolismo , Biologia Computacional , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Doença Crônica
9.
J Med Case Rep ; 18(1): 303, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918846

RESUMO

BACKGROUND: Hemorrhage is the most common major complication after liver biopsy. Hemothorax is one type of bleeding and is very rare and dangerous. Several cases of hemothorax subsequent to liver biopsy have been documented, primarily attributed to injury of the intercostal artery or inferior phrenic artery and a few resulting from lung tissue damage; however, no previous case report of hemothorax caused by injury of musculophrenic artery after liver biopsy has been reported. CASE PRESENTATION: A 45-year-old native Chinese woman diagnosed with primary biliary cirrhosis due to long-term redness in urination and abnormal blood test indicators was admitted to our hospital for an ultrasound-guided liver biopsy to clarify pathological characteristics and disease staging. A total of 2 hours after surgery, the patient complained of discomfort in the right chest and abdomen. Ultrasound revealed an effusion in the right thorax and hemothorax was strongly suspected. The patient was immediately referred to the interventional department for digital subtraction angiography. Super-selective angiography of the right internal thoracic artery was performed which revealed significant contrast medium extravasation from the right musculophrenic artery, the terminal branch of the internal thoracic artery. Embolization was performed successfully. The vital signs of the patient were stabilized after the transarterial embolization and supportive treatment. CONCLUSION: This case draws attention to the musculophrenic artery as a potential source of hemorrhage after percutaneous liver biopsy.


Assuntos
Embolização Terapêutica , Hemotórax , Fígado , Humanos , Hemotórax/etiologia , Feminino , Pessoa de Meia-Idade , Fígado/patologia , Fígado/diagnóstico por imagem , Fígado/irrigação sanguínea , Ultrassonografia de Intervenção , Biópsia Guiada por Imagem/efeitos adversos , Angiografia Digital
10.
Food Chem ; 458: 140093, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38943960

RESUMO

This study evaluated the effects of postharvest ripening (0-6 days, D0-6) on cell wall pectin profile, infrared-assisted hot air-drying characteristics, and sugar content. Results showed that during postharvest ripening progress, the content of water-soluble pectin (WSP) and chelate-soluble pectin (CSP) increased while the content of Na2CO3-soluble pectin (NSP) and hemicellulose (HC) decreased. In addition, the average molecular weight of WSP increased while the average molecular weight of NSP decreased. Secondly, the drying time of plums with different postharvest ripening periods was in the order: D3 < D4 < D2 < D1 < D0 < D5 < D6. Furthermore, the sugar content of dried plums was mainly influenced by drying time, with three stages of sugar changes observed, tied to moisture content: (1) Sucrose hydrolyzes (50-85%); (2) Fructose and glucose degrade (15-50%); (3) Sorbitol degrades (15-42%). These findings indicate that the transformation of cell wall pectin profile during the postharvest ripening process alters drying behavior and regulates the sugar content of dried plums. CHEMICAL COMPOUNDS STUDIED IN THIS ARTICLE: Galacturonic acid (PubChem CID: 439215); Acetone (PubChem CID: 180); Distilled water (PubChem CID: 962); Trans-1,2-Diaminocyclohexane-N, N, N, N'-tetraacetic acid (PubChem CID: 2723845); Na2CO3 (PubChem CID: 10340); Glucose (PubChem CID: 5793); fructose (PubChem CID: 2723872) sucrose (PubChem CID: 5988) sorbitol (PubChem CID: 5780) and Sodium borohydride (PubChem CID: 4311764).


Assuntos
Parede Celular , Frutas , Pectinas , Pectinas/metabolismo , Pectinas/química , Pectinas/análise , Parede Celular/química , Parede Celular/metabolismo , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Dessecação , Prunus domestica/química , Prunus domestica/metabolismo , Prunus domestica/crescimento & desenvolvimento , Açúcares/metabolismo , Açúcares/análise , Manipulação de Alimentos
11.
Int J Biol Macromol ; 273(Pt 2): 133148, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38897517

RESUMO

Polylactic acid (PLA), as a green functional polymer, has been useful in various coating applications. However, due to the low mechanical strength and thermal stability of PLA, it needs to be improved in order to expand its application areas. In this work, a series of polylactic acid (PLA) nanocomposite films were prepared through introducing polydopamine-modified mica (PDA@MICA) as a self-assemble nanofiller to enhance its mechanical and thermal properties. The results demonstrated that PLA/PDA@MICA shows excellent mechanical properties. Tensile tests showed that PLA/PDA@MICA exhibits a 58.3 % increase in tensile strength and a 16.8 % increase in Young's modulus compared to pure PLA. Meanwhile, thermal performance testing shown the introduction of PDA@MICA led to an increase in crystallinities (Xc = 24.78 %). And the thermal decomposition temperature of PLA/PDA@MICA film (374 °C) was slightly higher than that of PLA film (367 °C). The simultaneous improvement of the mechanical and thermal properties was attributed to the formation of hydrogen bonds between PLA and PDA@MICA. In addition, the parallel arrangement of PDA@MICA and PLA macromolecular chains forms a unique "brick and mortar" structure in the coating, which enhances the mechanical properties of PLA/PDA@MICA composite coatings. This study reports a successful approach to simultaneously address the drawbacks of PLA, specifically its low thermal stability and mechanical strength, thereby promoting its widespread application in the coatings industry.


Assuntos
Silicatos de Alumínio , Indóis , Poliésteres , Polímeros , Resistência à Tração , Polímeros/química , Poliésteres/química , Silicatos de Alumínio/química , Indóis/química , Temperatura , Fenômenos Mecânicos , Nanocompostos/química , Animais , Módulo de Elasticidade
12.
bioRxiv ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38903079

RESUMO

Poly(A)-binding protein (Pab1 in yeast) is involved in mRNA decay and translation initiation, but its molecular functions are incompletely understood. We found that auxin-induced degradation of Pab1 reduced bulk mRNA and polysome abundance in a manner suppressed by deleting the catalytic subunit of decapping enzyme (dcp2Δ), demonstrating that enhanced decapping/degradation is the major driver of reduced mRNA abundance and protein synthesis at limiting Pab1 levels. An increased median poly(A) tail length conferred by Pab1 depletion was also nullified by dcp2Δ, suggesting that mRNA isoforms with shorter tails are preferentially decapped/degraded at limiting Pab1. In contrast to findings on mammalian cells, the translational efficiencies (TEs) of many mRNAs were altered by Pab1 depletion; however, these changes were broadly diminished by dcp2∆, suggesting that reduced mRNA abundance is a major driver of translational reprogramming at limiting Pab1. Thus, assembly of the closed-loop mRNP via PABP-eIF4G interaction appears to be dispensable for normal translation of most yeast mRNAs in vivo. Interestingly, histone mRNAs and proteins are preferentially diminished on Pab1 depletion dependent on Dcp2, accompanied by activation of internal cryptic promoters in the manner expected for reduced nucleosome occupancies, revealing a new layer of post-transcriptional control of histone gene expression.

13.
Front Neurosci ; 18: 1368552, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716255

RESUMO

Probucol has been utilized as a cholesterol-lowering drug with antioxidative properties. However, the impact and fundamental mechanisms of probucol in obesity-related cognitive decline are unclear. In this study, male C57BL/6J mice were allocated to a normal chow diet (NCD) group or a high-fat diet (HFD) group, followed by administration of probucol to half of the mice on the HFD regimen. Subsequently, the mice were subjected to a series of behavioral assessments, alongside the measurement of metabolic and redox parameters. Notably, probucol treatment effectively alleviates cognitive and social impairments induced by HFD in mice, while exhibiting no discernible influence on mood-related behaviors. Notably, the beneficial effects of probucol arise independently of rectifying obesity or restoring systemic glucose and lipid homeostasis, as evidenced by the lack of changes in body weight, serum cholesterol levels, blood glucose, hyperinsulinemia, systemic insulin resistance, and oxidative stress. Instead, probucol could regulate the levels of nitric oxide and superoxide-generating proteins, and it could specifically alleviate HFD-induced hippocampal insulin resistance. These findings shed light on the potential role of probucol in modulating obesity-related cognitive decline and urge reevaluation of the underlying mechanisms by which probucol exerts its beneficial effects.

14.
Acta Neuropathol Commun ; 12(1): 66, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654316

RESUMO

The elderly frequently present impaired blood-brain barrier which is closely associated with various neurodegenerative diseases. However, how the albumin, the most abundant protein in the plasma, leaking through the disrupted BBB, contributes to the neuropathology remains poorly understood. We here demonstrated that mouse serum albumin-activated microglia induced astrocytes to A1 phenotype to remarkably increase levels of Elovl1, an astrocytic synthase for very long-chain saturated fatty acids, significantly promoting VLSFAs secretion and causing neuronal lippoapoptosis through endoplasmic reticulum stress response pathway. Moreover, MSA-activated microglia triggered remarkable tau phosphorylation at multiple sites through NLRP3 inflammasome pathway. Intracerebroventricular injection of MSA into the brains of C57BL/6J mice to a similar concentration as in patient brains induced neuronal apoptosis, neuroinflammation, increased tau phosphorylation, and decreased the spatial learning and memory abilities, while Elovl1 knockdown significantly prevented the deleterious effect of MSA. Overall, our study here revealed that MSA induced tau phosphorylation and neuron apoptosis based on MSA-activated microglia and astrocytes, respectively, showing the critical roles of MSA in initiating the occurrence of tauopathies and cognitive decline, and providing potential therapeutic targets for MSA-induced neuropathology in multiple neurodegenerative disorders.


Assuntos
Apoptose , Camundongos Endogâmicos C57BL , Neurônios , Albumina Sérica , Tauopatias , Animais , Humanos , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Astrócitos/metabolismo , Astrócitos/patologia , Astrócitos/efeitos dos fármacos , Elongases de Ácidos Graxos/metabolismo , Microglia/metabolismo , Microglia/efeitos dos fármacos , Microglia/patologia , Neurônios/metabolismo , Neurônios/patologia , Neurônios/efeitos dos fármacos , Albumina Sérica/metabolismo , Albumina Sérica/farmacologia , Proteínas tau/metabolismo , Tauopatias/patologia , Tauopatias/metabolismo
15.
Cell Death Discov ; 10(1): 167, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589400

RESUMO

The neurotoxic α-synuclein (α-syn) oligomers play an important role in the occurrence and development of Parkinson's disease (PD), but the factors affecting α-syn generation and neurotoxicity remain unclear. We here first found that thrombomodulin (TM) significantly decreased in the plasma of PD patients and brains of A53T α-syn mice, and the increased TM in primary neurons reduced α-syn generation by inhibiting transcription factor p-c-jun production through Erk1/2 signaling pathway. Moreover, TM decreased α-syn neurotoxicity by reducing the levels of oxidative stress and inhibiting PAR1-p53-Bax signaling pathway. In contrast, TM downregulation increased the expression and neurotoxicity of α-syn in primary neurons. When TM plasmids were specifically delivered to neurons in the brains of A53T α-syn mice by adeno-associated virus (AAV), TM significantly reduced α-syn expression and deposition, and ameliorated the neuronal apoptosis, oxidative stress, gliosis and motor deficits in the mouse models, whereas TM knockdown exacerbated these neuropathology and motor dysfunction. Our present findings demonstrate that TM plays a neuroprotective role in PD pathology and symptoms, and it could be a novel therapeutic target in efforts to combat PD. Schematic representation of signaling pathways of TM involved in the expression and neurotoxicity of α-syn. A TM decreased RAGE, and resulting in the lowered production of p-Erk1/2 and p-c-Jun, and finally reduce α-syn generation. α-syn oligomers which formed from monomers increase the expression of p-p38, p53, C-caspase9, C-caspase3 and Bax, decrease the level of Bcl-2, cause mitochondrial damage and lead to oxidative stress, thus inducing neuronal apoptosis. TM can reduce intracellular oxidative stress and inhibit p53-Bax signaling by activating APC and PAR-1. B The binding of α-syn oligomers to TLR4 may induce the expression of IL-1ß, which is subsequently secreted into the extracellular space. This secreted IL-1ß then binds to its receptor, prompting p65 to translocate from the cytoplasm into the nucleus. This translocation downregulates the expression of KLF2, ultimately leading to the suppression of TM expression. By Figdraw.

16.
Emerg Microbes Infect ; 13(1): 2343909, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38616729

RESUMO

The recent emergence of a SARS-CoV-2 saltation variant, BA.2.87.1, which features 65 spike mutations relative to BA.2, has attracted worldwide attention. In this study, we elucidate the antigenic characteristics and immune evasion capability of BA.2.87.1. Our findings reveal that BA.2.87.1 is more susceptible to XBB-induced humoral immunity compared to JN.1. Notably, BA.2.87.1 lacks critical escaping mutations in the receptor binding domain (RBD) thus allowing various classes of neutralizing antibodies (NAbs) that were escaped by XBB or BA.2.86 subvariants to neutralize BA.2.87.1, although the deletions in the N-terminal domain (NTD), specifically 15-23del and 136-146del, compensate for the resistance to humoral immunity. Interestingly, several neutralizing antibody drugs have been found to restore their efficacy against BA.2.87.1, including SA58, REGN-10933 and COV2-2196. Hence, our results suggest that BA.2.87.1 may not become widespread until it acquires multiple RBD mutations to achieve sufficient immune evasion comparable to that of JN.1.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Evasão da Resposta Imune , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Anticorpos Neutralizantes/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/imunologia , COVID-19/virologia , Anticorpos Antivirais/imunologia , Humanos , Mutação , Animais , Antígenos Virais/imunologia , Antígenos Virais/genética , Imunidade Humoral
17.
J Ethnopharmacol ; 328: 118116, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548118

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Aristolochic acids (AAs) are naturally occurring nitro phenanthrene carboxylic acids primarily found in plants of the Aristolochiaceae family. Aristolochic acid D (AAD) is a major constituent in the roots and rhizomes of the Chinese herb Xixin (the roots and rhizomes of Asarum heterotropoides F. Schmidt), which is a key material for preparing a suite of marketed Chinese medicines. Structurally, AAD is nearly identical to the nephrotoxic aristolochic acid I (AAI), with an additional phenolic group at the C-6 site. Although the nephrotoxicity and metabolic pathways of AAI have been well-investigated, the metabolic pathway(s) of AAD in humans and the influence of AAD metabolism on its nephrotoxicity has not been investigated yet. AIM OF THE STUDY: To identify the major metabolites of AAD in human tissues and to characterize AAD O-glucuronidation kinetics in different enzyme sources, as well as to explore the influence of AAD O-glucuronidation on its nephrotoxicity. MATERIALS AND METHODS: The O-glucuronide of AAD was biosynthesized and its chemical structure was fully characterized by both 1H-NMR and 13C-NMR. Reaction phenotyping assays, chemical inhibition assays, and enzyme kinetics analyses were conducted to assess the crucial enzymes involved in AAD O-glucuronidation in humans. Docking simulations were performed to mimic the catalytic conformations of AAD in human UDP-glucuronosyltransferases (UGTs), while the predicted binding energies and distances between the deprotonated C-6 phenolic group of AAD and the glucuronyl moiety of UDPGA in each tested human UGT isoenzyme were measured. The mitochondrial membrane potentials (MMP) and reactive oxygen species (ROS) levels in HK-2 cells treated with either AAI, or AAD, or AAD O-glucuronide were tested, to elucidate the impact of O-glucuronidation on the nephrotoxicity of AAD. RESULTS: AAD could be rapidly metabolized in human liver and intestinal microsomes (HLM and HIM, respectively) to form a mono-glucuronide, which was purified and fully characterized as AAD-6-O-ß-D-glucuronide (AADG) by NMR. UGT1A1 was the predominant enzyme responsible for AAD-6-O-glucuronidation, while UGT1A9 contributed to a lesser extent. AAD-6-O-glucuronidation in HLM, HIM, UGT1A1 and UGT1A9 followed Michaelis-Menten kinetics, with the Km values of 4.27 µM, 9.05 µM, 3.87 µM, and 7.00 µM, respectively. Docking simulations suggested that AAD was accessible to the catalytic cavity of UGT1A1 or UGT1A9 and formed catalytic conformations. Further investigations showed that both AAI and AAD could trigger the elevated intracellular ROS levels and induce mitochondrial dysfunction and in HK-2 cells, but AADG was hardly to trigger ROS accumulation and mitochondrial dysfunction. CONCLUSION: Collectively, UGT1A-catalyzed AAD 6-O-glucuronidation represents a crucial detoxification pathway of this naturally occurring AAI analogs in humans, which is very different from that of AAI.


Assuntos
Ácidos Aristolóquicos , Doenças Mitocondriais , Humanos , Ácidos Aristolóquicos/toxicidade , Glucuronídeos/metabolismo , Microssomos Hepáticos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Glucuronosiltransferase/metabolismo , Cinética , Catálise , Difosfato de Uridina/metabolismo
18.
Pharmaceuticals (Basel) ; 17(2)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38399453

RESUMO

Immunotherapy has shown clinical benefit in patients with non-small-cell lung cancer (NSCLC). Due to the limited response of monotherapy, combining immune checkpoint inhibitors (ICIs) and chemotherapy is considered a treatment option for advanced NSCLC. However, the mechanism of combined therapy and the potential patient population that could benefit from combined therapy remain undetermined. Here, we developed an NSCLC model based on the published quantitative systems pharmacology (QSP)-immuno-oncology platform by making necessary adjustments. After calibration and validation, the established QSP model could adequately characterise the biological mechanisms of action of the triple combination of atezolizumab, nab-paclitaxel, and carboplatin in patients with NSCLC, and identify predictive biomarkers for precision dosing. The established model could efficiently characterise the objective response rate and duration of response of the IMpower131 trial, reproducing the efficacy of alternative dosing. Furthermore, CD8+ and CD4+ T cell densities in tumours were found to be significantly related to the response status. This significant extension of the QSP model not only broadens its applicability but also more accurately reflects real-world clinical settings. Importantly, it positions the model as a critical foundation for model-informed drug development and the customisation of treatment plans, especially in the context of combining single-agent ICIs with platinum-doublet chemotherapy.

19.
Insect Sci ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38414321

RESUMO

The fall armyworm (FAW), Spodoptera frugiperda, has colonized and caused consistent damage in the Eastern hemisphere. The identification of various FAW strains is essential for developing precise prevention and control measures. The triosephosphate isomerase (Tpi) gene is recognized as an effective marker closely linked to FAW subpopulations. However, most current studies primarily focus on the comparison of variations in specific gene sites of this gene. In this study, we conducted full-length sequencing of the Tpi genes from 5 representative FAW groups. Our findings revealed that the Tpi genes varied in length from 1220 to 1420 bp, with the primary variation occurring within 4 introns. Notably, the exon lengths remained consistent, at 747 bp, with 37 observed base variations; however, no amino acid variations were detected. Through sequence alignment, we identified 8 stable variation sites that can be used to distinguish FAW strains in the Eastern hemisphere. Additionally, we performed strain identification on 1569 FAW samples collected from 19 provinces in China between 2020 and 2021. The extensive analysis indicated the absence of the rice strain in the samples. Instead, we only detected the presence of the corn strain and the Zambia strain, with the Zambia strain being distributed in a very low proportion (3.44%). Furthermore, the corn strain could be further categorized into 2 subgroups. This comprehensive study provides a valuable reference for enhancing our understanding of FAW population differentiation and for improving monitoring and early warning efforts.

20.
Mol Ther ; 32(3): 637-645, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38204163

RESUMO

N-Acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) therapies have received approval for treating both orphan and prevalent diseases. To improve in vivo efficacy and streamline the chemical synthesis process for efficient and cost-effective manufacturing, we conducted this study to identify better designs of GalNAc-siRNA conjugates for therapeutic development. Here, we present data on redesigned GalNAc-based ligands conjugated with siRNAs against angiopoietin-like 3 (ANGPTL3) and lipoprotein (a) (Lp(a)), two target molecules with the potential to address large unmet medical needs in atherosclerotic cardiovascular diseases. By attaching a novel pyran-derived scaffold to serial monovalent GalNAc units before solid-phase oligonucleotide synthesis, we achieved increased GalNAc-siRNA production efficiency with fewer synthesis steps compared to the standard triantennary GalNAc construct L96. The improved GalNAc-siRNA conjugates demonstrated equivalent or superior in vivo efficacy compared to triantennary GalNAc-conjugated siRNAs.


Assuntos
Doenças Cardiovasculares , Hepatócitos , Humanos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/química , Análise Custo-Benefício , RNA de Cadeia Dupla , Acetilgalactosamina/química , Proteína 3 Semelhante a Angiopoietina
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