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1.
PLoS Pathog ; 19(7): e1011550, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37498975

RESUMO

Influenza A virus (IAV) expresses several accessory proteins to limit host anti-viral restriction factors to facilitate viral replication. The Ten-Eleven Translocation 2 (TET2) is a methylcytosine dioxygenase that promotes DNA demethylation by catalyzing the oxidation of 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC), which plays a vital role in hematopoiesis and immunity. Here we report that TET2 is a host restriction factor that limits IAV replication. But IAV endoribonuclease PA-X is able to remove the replication restriction by binding to TET2 mRNA and driving TET2 mRNA degradation to reduce TET2 expression during infection. Genetic inactivation of TET2 markedly enhances IAV replication in vitro and in vivo. Mechanistically, we found that TET2 regulates demethylation and transcription of STAT1 and some interferon-stimulated genes (ISGs), including ISG15, ISG20, and IFIT5, so the loss of TET2 greatly impairs type I Interferon signaling. Furthermore, we confirmed that TET2-mediated demethylation of the STAT1 gene is critical for interferon anti-viral activity. Our study demonstrates that the host TET2 is essential to the innate immune response against IAV infection.


Assuntos
Vírus da Influenza A , Interferon Tipo I , Endorribonucleases , Imunidade Inata , Replicação Viral , Interferon Tipo I/metabolismo
2.
Nucleic Acids Res ; 51(8): 3820-3835, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36912090

RESUMO

Natural transformation is one of the major mechanisms of horizontal gene transfer. Although it is usually studied using purified DNA in the laboratory, recent studies showed that many naturally competent bacteria acquired exogenous DNA from neighboring donor cells. Our previous work indicates that cell-to-cell natural transformation (CTCNT) using two different Bacillus subtilis strains is a highly efficient process; however, the mechanism is unclear. In this study, we further characterized CTCNT and mapped the transferred DNA in the recombinants using whole genome sequencing. We found that a recombinant strain generated by CTCNT received up to 66 transferred DNA segments; the average length of acquired continuous DNA stretches was approximately 27 kb with a maximum length of 347 kb. Moreover, up to 1.54 Mb genomic DNA (37% of the chromosome) was transferred from the donors into one recipient cell. These results suggest that B. subtilis CTCNT facilitates horizontal gene transfer by increasing the transfer of DNA segments and fostering the exchange of large continuous genomic regions. This indicates that the potency of bacterial natural transformation is underestimated using traditional approaches and reveals that DNA donor cells may play an important role in the transformation process in natural environments.


Assuntos
Bacillus subtilis , Transformação Bacteriana , Bacillus subtilis/genética , DNA/genética , DNA Bacteriano/genética , Genoma , Genômica
3.
Mol Cancer ; 23(1): 113, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802795

RESUMO

BACKGROUND: The role of circRNAs in hepatocellular carcinoma (HCC) progression remains unclear. CircPIAS1 (circBase ID: hsa_circ_0007088) was identified as overexpressed in HCC cases through bioinformatics analysis. This study aimed to investigate the oncogenic properties and mechanisms of circPIAS1 in HCC development. METHODS: Functional analyses were conducted to assess circPIAS1's impact on HCC cell proliferation, migration, and ferroptosis. Xenograft mouse models were employed to evaluate circPIAS1's effects on tumor growth and pulmonary metastasis in vivo. Bioinformatics analysis, RNA immunoprecipitation, and luciferase reporter assays were utilized to elucidate the molecular pathways influenced by circPIAS1. Additional techniques, including RNA pulldown, fluorescence in situ hybridization (FISH), chromatin immunoprecipitation (ChIP), qPCR, and western blotting, were used to further explore the underlying mechanisms. RESULTS: CircPIAS1 expression was elevated in HCC tissues and cells. Silencing circPIAS1 suppressed HCC cell proliferation and migration both in vitro and in vivo. Mechanically, circPIAS1 overexpression inhibited ferroptosis by competitively binding to miR-455-3p, leading to upregulation of Nuclear Protein 1 (NUPR1). Furthermore, NUPR1 promoted FTH1 transcription, enhancing iron storage in HCC cells and conferring resistance to ferroptosis. Treatment with ZZW-115, an NUPR1 inhibitor, reversed the tumor-promoting effects of circPIAS1 and sensitized HCC cells to lenvatinib. CONCLUSION: This study highlights the critical role of circPIAS1 in HCC progression through modulation of ferroptosis. Targeting the circPIAS1/miR-455-3p/NUPR1/FTH1 regulatory axis may represent a promising therapeutic strategy for HCC.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Carcinoma Hepatocelular , Proliferação de Células , Ferroptose , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , MicroRNAs , Proteínas de Neoplasias , RNA Circular , Animais , Feminino , Humanos , Masculino , Camundongos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Progressão da Doença , Ferroptose/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , RNA Circular/genética , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Appl Clin Med Phys ; 25(4): e14259, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38317597

RESUMO

BACKGROUND: The treatment planning process from segmentation to producing a deliverable plan is time-consuming and labor-intensive. Existing solutions automate the segmentation and planning processes individually. The feasibility of combining auto-segmentation and auto-planning for volumetric modulated arc therapy (VMAT) for rectal cancers in an end-to-end process is not clear. PURPOSE: To create and clinically evaluate a complete end-to-end process for auto-segmentation and auto-planning of VMAT for rectal cancer requiring only the gross tumor volume contour and a CT scan as inputs. METHODS: Patient scans and data were retrospectively selected from our institutional records for patients treated for malignant neoplasm of the rectum. We trained, validated, and tested deep learning auto-segmentation models using nnU-Net architecture for clinical target volume (CTV), bowel bag, large bowel, small bowel, total bowel, femurs, bladder, bone marrow, and female and male genitalia. For the CTV, we identified 174 patients with clinically drawn CTVs. We used data for 18 patients for all structures other than the CTV. The structures were contoured under the guidance of and reviewed by a gastrointestinal (GI) radiation oncologist. The predicted results for CTV in 35 patients and organs at risk (OAR) in six patients were scored by the GI radiation oncologist using a five-point Likert scale. For auto-planning, a RapidPlan knowledge-based planning solution was modeled for VMAT delivery with a prescription of 25 Gy in five fractions. The model was trained and tested on 20 and 34 patients, respectively. The resulting plans were scored by two GI radiation oncologists using a five-point Likert scale. Finally, the end-to-end pipeline was evaluated on 16 patients, and the resulting plans were scored by two GI radiation oncologists. RESULTS: In 31 of 35 patients, CTV contours were clinically acceptable without necessary modifications. The CTV achieved a Dice similarity coefficient of 0.85 (±0.05) and 95% Hausdorff distance of 15.25 (±5.59) mm. All OAR contours were clinically acceptable without edits, except for large and small bowel which were challenging to differentiate. However, contours for total, large, and small bowel were clinically acceptable. The two physicians accepted 100% and 91% of the auto-plans. For the end-to-end pipeline, the two physicians accepted 88% and 62% of the auto-plans. CONCLUSIONS: This study demonstrated that the VMAT treatment planning technique for rectal cancer can be automated to generate clinically acceptable and safe plans with minimal human interventions.


Assuntos
Radioterapia de Intensidade Modulada , Neoplasias Retais , Humanos , Masculino , Feminino , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Dosagem Radioterapêutica , Neoplasias Retais/radioterapia , Reto , Órgãos em Risco , Planejamento da Radioterapia Assistida por Computador/métodos
5.
J Transl Med ; 21(1): 90, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36747249

RESUMO

BACKGROUND: Observational studies have found that both short and long sleep duration are associated with increased risk of metabolic syndrome (MetS). This study aimed to examine the associations of genetically determined sleep durations with MetS and its five components (i.e., central obesity, high blood pressure, dyslipidemia, hypertriglyceridemia, and hyperglycemia) among a group of elderly population. METHODS: In 335,727 participants of White British from the UK Biobank, linear Mendelian randomization (MR) methods were first employed to examine the causal association of genetically predicted continuous sleep duration with MetS and its each component. Nonlinear MR analyses were performed to determine the nonlinearity of these associations. The causal associations of short and long sleep duration with MetS and its components were further assessed by using genetic variants that associated with short (≤ 6 h) and long sleep (≥ 9 h) durations. RESULTS: Linear MR analyses demonstrated that genetically predicted 1-h longer sleep duration was associated with a 13% lower risk of MetS, a 30% lower risk of central obesity, and a 26% lower risk of hyperglycemia. Non-linear MR analyses provided evidence for non-linear associations of genetically predicted sleep duration with MetS and its five components (all P values < 0.008). Genetically predicted short sleep duration was moderately associated with MetS and its four components, including central obesity, dyslipidemia, hypertriglyceridemia, and hyperglycemia (all P values < 0.002), whereas genetically long sleep duration was not associated with MetS and any of its components. CONCLUSIONS: Genetically predicted short sleep duration, but not genetically predicted long sleep duration, is a potentially causal risk factor for MetS.


Assuntos
Dislipidemias , Hiperglicemia , Hipertrigliceridemia , Síndrome Metabólica , Humanos , Idoso , Obesidade Abdominal/complicações , Análise da Randomização Mendeliana , Fatores de Risco , Obesidade/complicações , Sono/genética , Hiperglicemia/complicações , Hiperglicemia/genética , Dislipidemias/complicações , Hipertrigliceridemia/complicações , Estudo de Associação Genômica Ampla
6.
J Org Chem ; 88(14): 9811-9822, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37401110

RESUMO

Catalytic selective annulation of 2H-azirines constitutes a general and modular strategy for the generation of molecular complexity. By using Pd-catalyzed ring opening/heterocyclization associated with direct cleavage of C-N and C-C bonds under appropriate conditions, the formation of imidazoles is presented. Alternatively, the silver-catalyzed radical [3 + 2] cycloannulation of 2H-azirines and 1,3-dicarbonyl compounds provides highly functionalized pyrrole derivatives. Both aliphatic cyclic and acyclic diketones are tolerated with good regioselectivity. Moreover, a radical capture experiment was carried out to determine the proposed mechanism, providing support for a facile radical process.

7.
Phys Chem Chem Phys ; 25(5): 4297-4304, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36688602

RESUMO

Monolayer transition metal dichalcogenides (TMDs), typical two-dimensional semiconductors, have been extensively studied for their extraordinary physical properties and utilized for nanoelectronics and optoelectronics. However, the finite samples and discontinuity in the synthesis process of TMD materials definitely induce defect edges in nanoribbons and greatly influence the device performance. Here, we systematically studied the atomic structures, energetic and mechanical stability, and electronic and catalytic properties of MoSe2 nanoribbons on the basis of experiments. Clear benefits of ZZSe-Mo-NW30 edged nanoribbons were found to evidently increase the dynamic stability according to our first-principles calculations. Meanwhile, unsaturated Mo atoms at the edge sites induced local magnetic moments up to 0.54 µB and changed the chemical environments of adjacent Se atoms, which acted as active sites for the hydrogen evolution reaction (HER) with a lower onset potential of -0.04 eV. The external tensile strain on these nanoribbons can have negligible effects on the electronic and catalytic properties. The onset potential of the ZZSe-Mo-NW30 edged nanoribbons only changed 0.03 eV under critical tensile strain. The atomic-scale research of edge reconstructions in TMD materials provides new opportunities to modulate the synthesis mechanism for experiments and defect-engineering applications in electrochemical catalysts.

8.
Pharm Dev Technol ; 28(3-4): 351-362, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36971746

RESUMO

Toad skin has many pharmacological activities and bufadienolides are regarded as its main anti-tumor components. The poor water solubility, high toxicity, rapid elimination and less selectivity in vivo of bufadienolides limit the application of toad skin. Based on the "unification of drugs and excipients" theory, the toad skin extracts (TSE) and Brucea javanica oil (BJO) nanoemulsions (NEs) were designed to solve the aforementioned problems. BJO as the main oil phase was not only used to prepare the NEs, but played a synergistic therapeutic role combined with TSE. TSE-BJO NEs showed 155 nm particle size, entrapment efficiency of >95% and good stability. TSE-BJO NEs demonstrated superior anti-tumor activity compared with the TSE or BJO NEs alone. The mechanism of TSE-BJO NEs to enhance the antineoplastic efficacy involved several pathways, such as inhibiting cell proliferation, inducing tumor cell apoptosis >40% and arresting cell cycle at G2/M. TSE-BJO NEs could co-deliver drugs into the target cells efficiently and exhibit satisfying synergism. Besides, TSE-BJO NEs facilitated the long circulation of bufadienolides contributing to the high accumulation of drugs at tumor sites and the improvement of anti-tumor efficacy. The study achieves the combinative administration of the toxic TSE and BJO with high efficacy and safety.


Assuntos
Antineoplásicos , Óleos de Plantas , Preparações Farmacêuticas , Excipientes , Antineoplásicos/farmacologia , Proliferação de Células , Emulsões/farmacologia
9.
Int J Neuropsychopharmacol ; 25(5): 361-374, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34893841

RESUMO

BACKGROUND: Odor identification (OI) dysfunction is an early marker of Alzheimer's disease (AD), but it remains unclear how olfactory-related regions change from stages of subjective cognitive decline (SCD) and mild cognitive impairment (MCI) to AD dementia. METHODS: Two hundred and sixty-nine individuals were recruited in the present study. The olfactory-related regions were defined as the regions of interest, and the grey matter volume (GMV), low-frequency fluctuation, regional homogeneity (ReHo), and functional connectivity (FC) were compared for exploring the changing pattern of structural and functional abnormalities across AD, MCI, SCD, and normal controls. RESULTS: From the SCD, MCI to AD groups, the reduced GMV, increased low-frequency fluctuation, increased ReHo, and reduced FC of olfactory-related regions became increasingly severe, and only the degree of reduced GMV of hippocampus and caudate nucleus clearly distinguished the 3 groups. SCD participants exhibited reduced GMV (hippocampus, etc.), increased ReHo (caudate nucleus), and reduced FC (hippocampus-hippocampus and hippocampus-parahippocampus) in olfactory-related regions compared with normal controls. Additionally, reduced GMV of the bilateral hippocampus and increased ReHo of the right caudate nucleus were associated with OI dysfunction and global cognitive impairment, and they exhibited partially mediated effects on the relationships between OI and global cognition across all participants. CONCLUSION: Structural and functional abnormalities of olfactory-related regions present early with SCD and deepen with disease severity in the AD spectrum. The hippocampus and caudate nucleus may be the hub joining OI and cognitive function in the AD spectrum.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Hipocampo , Humanos , Imageamento por Ressonância Magnética
10.
BMC Med ; 19(1): 223, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34592968

RESUMO

BACKGROUND: With the identification of new targetable drivers and the recent emergence of novel targeted drugs, using comprehensive genomic profiling in lieu of the routine testing for classic drivers in the clinical care for advanced NSCLC has been increasingly advocated. However, the key assumption justifying this practice, that comprehensive genomic profiling could lead to effective anticancer therapies and improve patient outcomes, remains unproved. METHODS: Comprehensive genomic profiling was prospectively applied in 1564 advanced NSCLC patients to identify potentially actionable genomic alterations. Patients were assigned to genotype-matched targeted therapies or nonmatched therapies based on the profiling results. Its utility in directing treatments was determined by the proportion of patients receiving genotype-matched targeted therapies and the proportion of patients being enrolled into genotype-matched clinical trials. Its impacts on patient outcomes were assessed by comparing progression-free survival (PFS) and overall survival (OS) between patients who received a genotype-matched and nonmatched therapy. RESULTS: From October 2016 to October 2019, tumor genomic profiles were established in 1166 patients, leading to a matched targeted therapy in 37.7% (n = 440) and a genotype-matched trial enrollment in 20.9% of patients (n = 244). Potentially actionable alterations were detected in 781 patients (67.0%). For these patients, a genomic profiling-directed matched therapy significantly improved PFS (9.0 months vs 4.9 months, P < 0.001) and OS (3.9 years vs 2.5 years, P < 0.001) compared with a nonmatched therapy. Excluding patients with standard targeted therapies, genomic profiling led to a matched targeted therapy in 16.7% (n = 24) and a matched trial enrollment in 11.2% (n = 16) of patients. No PFS (4.7 months vs 4.6 months, P = 0.530) or OS (1.9 years vs 2.4 years, P = 0.238) benefit was observed with the use of genotype-matched targeted therapies in this population. CONCLUSIONS: Comprehensive genomic profiling is of clinical utility in assisting treatment selection, facilitating clinical trial enrollment, and improving patient outcomes in advanced NSCLC. However, for patients carrying alterations without standard-of-care targeted drugs, the interpretation of genomic profiling results should be careful given the low likelihood of benefit from the investigational or off-label use of targeted therapies in this population in the current treatment landscape. TRIAL REGISTRATION: ChiCTR1900027582 (retrospectively registered on 19 November 2019).


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Genômica , Genótipo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação
11.
Ann Neurol ; 88(4): 817-829, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32691442

RESUMO

OBJECTIVE: The purpose of this study was to investigate the differences in actigraphy-measured rest-activity patterns (eg, sleep-wake cycle, circadian rest-activity rhythm, and physical activity) across different stages of α-synucleinopathy. METHODS: We compared alterations in 7-day actigraphy-measured rest-activity patterns among patients with clinically diagnosed α-synucleinopathies (n = 44), and their age-, sex-, and body mass index (BMI)-matched patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD, n = 88), and non-rapid eye movement (REM) sleep behavior disorder (RBD) controls (n = 44) in a case-control study (study 1) and between convertors (n = 22) and their age-, sex-, BMI-, iRBD-duration, and follow-up duration-matched non-convertors (n = 66) in a prospective nested case-control study (study 2). RESULTS: In study 1, there were significant increases (all p values were adjusted by false discovery rate < 0.01) in probable napping behaviors (percentage, duration, and episodes), activity fragmentation (estimated by kAR ), and physical inactivity during active periods across controls, and iRBD, to clinically diagnosed α-synucleinopathies. In study 2, higher levels (all p values were adjusted by false discovery rate < 0.05) of baseline objective probable napping, activity fragmentation, and physical inactivity during active periods were associated with the conversion of patients with iRBD into clinically diagnosed α-synucleinopathies at 2 years of follow-up with medium to large effect sizes (Cohen's d: 0.56 to 0.80). These findings were further supported by functional linear modeling analyses. INTERPRETATION: Rest-activity pattern alterations, mainly objective probable napping behaviors, activity fragmentation, and physical inactivity during active period, emerge as early as at the stage of iRBD, which serves as early and robust prodromal markers of the conversion of iRBD into clinically diagnosed α-synucleinopathies. ANN NEUROL 2020;88:817-829.


Assuntos
Sintomas Prodrômicos , Transtorno do Comportamento do Sono REM/diagnóstico , Sinucleinopatias/diagnóstico , Actigrafia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Angew Chem Int Ed Engl ; 60(10): 5414-5420, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33258169

RESUMO

4-Androstenedione (4-AD) and progesterone (PG) are two of the most important precursors for synthesis of steroid drugs, however their current manufacturing processes suffer from low efficiency and severe environmental issues. In this study, we decipher a dual-role reductase (mnOpccR) in the phytosterols catabolism, which engages in two different metabolic branches to produce the key intermediate 20-hydroxymethyl pregn-4-ene-3-one (4-HBC) through a 4-e reduction of 3-oxo-4-pregnene-20-carboxyl-CoA (3-OPC-CoA) and 2-e reduction of 3-oxo-4-pregnene-20-carboxyl aldehyde (3-OPA), respectively. Inactivation or overexpression of mnOpccR in the Mycobacterium neoaurum can achieve exclusive production of either 4-AD or 4-HBC from phytosterols. By utilizing a two-step synthesis, 4-HBC can be efficiently converted into PG in a scalable manner (100 gram scale). This study deciphers a pivotal biosynthetic mechanism of phytosterol catabolism and provides very efficient production routes of 4-AD and PG.


Assuntos
Proteínas de Bactérias/metabolismo , Oxirredutases/metabolismo , Fitosteróis/metabolismo , Pregnenos/metabolismo , Androstenodiona/síntese química , Proteínas de Bactérias/genética , Biocatálise , Mycobacteriaceae/enzimologia , Mycobacteriaceae/genética , Oxirredutases/genética , Pregnenos/química , Progesterona/síntese química
13.
Sensors (Basel) ; 20(17)2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878100

RESUMO

The design, analysis, and simulation of a new Micro-electromechanical System (MEMS) gyroscope based on differential tunneling magnetoresistance sensing are presented in this paper. The device is driven by electrostatic force, whereas the Coriolis displacements are transferred to intensity variations of magnetic fields, further detected by the Tunneling Magnetoresistance units. The magnetic fields are generated by a pair of two-layer planar multi-turn copper coils that are coated on the backs of the inner masses. Together with the dual-mass structure of proposed tuning fork gyroscope, a two-stage differential detection is formed, thereby enabling rejection of mechanical and magnetic common-mode errors concurrently. The overall conception is described followed by detailed analyses of proposed micro-gyroscope and rectangle coil. Subsequently, the FEM simulations are implemented to determine the mechanical and magnetic characteristics of the device separately. The results demonstrate that the micro-gyroscope has a mechanical sensitivity of 1.754 nm/°/s, and the micro-coil has a maximum sensitivity of 41.38 mOe/µm. When the detection height of Tunneling Magnetoresistance unit is set as 60 µm, the proposed device exhibits a voltage-angular velocity sensitivity of 0.131 mV/°/s with a noise floor of 7.713 × 10-6°/s/Hz in the absence of any external amplification.

14.
J Cell Physiol ; 234(3): 2807-2821, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30067871

RESUMO

The application of pulsed electromagnetic fields (PEMFs) in the prevention and treatment of osteoporosis has long been an area of interest. However, the clinical application of PEMFs remains limited because of the poor understanding of the PEMF action mechanism. Here, we report that PEMFs promote bone formation by activating soluble adenylyl cyclase (sAC), cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), and cAMP response element-binding protein (CREB) signaling pathways. First, it was found that 50 Hz 0.6 millitesla (mT) PEMFs promoted osteogenic differentiation of rat calvarial osteoblasts (ROBs), and that PEMFs activated cAMP-PKA-CREB signaling by increasing intracellular cAMP levels, facilitating phosphorylation of PKA and CREB, and inducing nuclear translocation of phosphorylated (p)-CREB. Blocking the signaling by adenylate cyclase (AC) and PKA inhibitors both abolished the osteogenic effect of PEMFs. Second, expression of sAC isoform was found to be increased significantly by PEMF treatment. Blocking sAC using sAC-specific inhibitor KH7 dramatically inhibited the osteogenic differentiation of ROBs. Finally, the peak bone mass of growing rats was significantly increased after 2 months of PEMF treatment with 90 min/day. The serum cAMP content, p-PKA, and p-CREB as well as the sAC protein expression levels were all increased significantly in femurs of treated rats. The current study indicated that PEMFs promote bone formation in vitro and in vivo by activating sAC-cAMP-PKA-CREB signaling pathway of osteoblasts directly or indirectly.


Assuntos
Inibidores Enzimáticos/farmacologia , Magnetoterapia , Osteogênese/efeitos da radiação , Osteoporose/terapia , Inibidores de Adenilil Ciclases/farmacologia , Adenilil Ciclases/genética , Adenilil Ciclases/farmacologia , Animais , Densidade Óssea/efeitos da radiação , Diferenciação Celular/efeitos da radiação , AMP Cíclico/antagonistas & inibidores , AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/genética , Modelos Animais de Doenças , Fêmur/crescimento & desenvolvimento , Fêmur/patologia , Fêmur/efeitos da radiação , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Osteoblastos/efeitos da radiação , Osteoporose/genética , Osteoporose/patologia , Ratos , Transdução de Sinais/efeitos da radiação
15.
Int Psychogeriatr ; 31(10): 1483-1489, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30696513

RESUMO

OBJECTIVES: Cognitive impairment in late-life depression is common and associated with a higher risk of all-cause dementia. Late-life depression patients with comorbid cardiovascular diseases (CVDs) or related risk factors may experience higher risks of cognitive deterioration in the short term. We aim to investigate the effect of CVDs and their related risk factors on the cognitive function of patients with late-life depression. METHODS: A total of 148 participants were recruited (67 individuals with late-life depression and 81 normal controls). The presence of hypertension, coronary heart disease, diabetes mellitus, or hyperlipidemia was defined as the presence of comorbid CVDs or related risk factors. Global cognitive functions were assessed at baseline and after a one-year follow-up by the Mini-Mental State Examination (MMSE). Global cognitive deterioration was defined by the reliable change index (RCI) of the MMSE. RESULTS: Late-life depression patients with CVDs or related risk factors were associated with 6.8 times higher risk of global cognitive deterioration than those without any of these comorbidities at a one-year follow-up. This result remained robust after adjusting for age, gender, and changes in the Hamilton Depression Rating Scale (HAMD) scores. CONCLUSIONS: This study suggests that late-life depression patients with comorbid CVDs or their related risk factors showed a higher risk of cognitive deterioration in the short-term (one-year follow up). Given that CVDs and their related risk factors are currently modifiable, active treatment of these comorbidities may delay rapid cognitive deterioration in patients with late-life depression.


Assuntos
Doenças Cardiovasculares/complicações , Disfunção Cognitiva/complicações , Depressão/complicações , Idoso , Idoso de 80 Anos ou mais , Cognição , Comorbidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
16.
Bioelectromagnetics ; 39(8): 569-584, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30350869

RESUMO

Microgravity is one of the main threats to the health of astronauts. Pulsed electromagnetic fields (PEMFs) have been considered as one of the potential countermeasures for bone loss induced by space flight. However, the optimal therapeutic parameters of PEMFs have not been obtained and the action mechanism is still largely unknown. In this study, a set of optimal therapeutic parameters for PEMFs (50 Hz, 0.6 mT 50% duty cycle and 90 min/day) selected based on high-throughput screening with cultured osteoblasts was used to prevent bone loss in rats induced by hindlimb suspension, a commonly accepted animal model to simulate the space environment. It was found that hindlimb suspension for 4 weeks led to significant decreases in femoral and vertebral bone mineral density (BMD) and their maximal loads, severe deterioration in bone micro-structure, and decreases in levels of bone formation markers and increases in bone resorption markers. PEMF treatment prevented about 50% of the decreased BMD and maximal loads, preserved the microstructure of cancellous bone and thickness of cortical bone, and inhibited decreases in bone formation markers. Histological analyses revealed that PEMFs significantly alleviated the reduction in osteoblast number and inhibited the increase in adipocyte number in the bone marrow. PEMFs also blocked decreases in serum levels of parathyroid hormone and its downstream signal molecule cAMP, and maintained the phosphorylation levels of protein kinase A (PKA) and cAMP response element-binding protein (CREB). The expression level of soluble adenylyl cyclases (sAC) was also maintained. It therefore can be concluded that PEMFs partially prevented the bone loss induced by weightless environment by maintaining bone formation through signaling of the sAC/cAMP/PKA/CREB pathway. Bioelectromagnetics. 39:569-584, 2018. © 2018 Wiley Periodicals, Inc.


Assuntos
Adenilil Ciclases/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Campos Eletromagnéticos , Membro Posterior/fisiologia , Osteogênese/efeitos da radiação , Adipócitos/citologia , Adipócitos/efeitos da radiação , Animais , Fenômenos Biomecânicos/efeitos da radiação , Peso Corporal/efeitos da radiação , Densidade Óssea/efeitos da radiação , Reabsorção Óssea/metabolismo , Reabsorção Óssea/prevenção & controle , Feminino , Fêmur/citologia , Fêmur/diagnóstico por imagem , Fêmur/fisiologia , Fêmur/efeitos da radiação , Membro Posterior/efeitos da radiação , Osteoblastos/citologia , Osteoblastos/efeitos da radiação , Ratos , Ratos Wistar , Transdução de Sinais/efeitos da radiação , Coluna Vertebral/citologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiologia , Coluna Vertebral/efeitos da radiação , Suspensões , Microtomografia por Raio-X
17.
Angew Chem Int Ed Engl ; 57(28): 8729-8733, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29797759

RESUMO

Natural photosynthesis serves as a model for energy and chemical conversions, and motivates the search of artificial systems that mimic nature's energy- and electron-transfer chains. However, bioinspired systems often suffer from the partial or even large loss of the charge separation state, and show moderate activity owing to the fundamentally different features of the multiple compounds. Herein, a selenium and cyanamide-functionalized heptazine-based melon (DA-HM) is designed as a unique bioinspired donor-acceptor (D-A) light harvester. The combination of the photosystem and electron shuttle in a single species, with both n- and p-type conductivities, and extended spectral absorption, endows DA-HM with a high efficiency in the transfer and separation of photoexcited charge carriers, resulting in photochemical activity. This work presents a unique conjugated polymeric system that shows great potential for solar-to-chemical conversion by artificial photosynthesis.

18.
Dement Geriatr Cogn Disord ; 43(5-6): 308-319, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28538242

RESUMO

BACKGROUND: The pattern of neuropsychiatric features of patients with neurosyphilis and the impact of the severity of cognitive impairment on neuropsychiatric syndromes are unknown. OBJECTIVE: We aim to assess the neuropsychiatric features of patients with neurosyphilis, and compare the impact of the severity of cognitive impairment on the neuropsychiatric syndromes between neurosyphilis and Alzheimer disease (AD). METHODS: Neuropsychiatric symptoms and the degree of cognitive impairment were assessed in a case-control study of 91 neurosyphilis, 162 AD, 157 mild cognitive impairment, and 139 normal controls by the Neuropsychiatric Inventory (NPI) scale and Clinical Dementia Rating scale, respectively. Factor analysis was performed on the 12 NPI items. RESULTS: Factor analysis showed that patients with neurosyphilis showed more severe neuropsychiatric syndromes at the dementia stage than those neurosyphilis patients at the mild cognitive impairment stage, while neuropsychiatric manifestations were equally common among the different stages of dementia (all p < 0.05). Frontal lobe syndrome was more severe in patients with neurosyphilis than in patients with AD from the early mild cognitive impairment stage to the moderate dementia stage (all p < 0.01). CONCLUSIONS: Patients with neurosyphilis show different patterns of neuropsychiatric syndromes at the mild cognitive impairment and dementia stages, and differ from patients with AD.


Assuntos
Disfunção Cognitiva , Demência , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Estudos de Casos e Controles , China/epidemiologia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Demência/complicações , Demência/diagnóstico , Demência/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Neurossífilis/complicações , Neurossífilis/diagnóstico , Neurossífilis/epidemiologia , Neurossífilis/psicologia , Índice de Gravidade de Doença
19.
Medicine (Baltimore) ; 103(15): e37744, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608118

RESUMO

RATIONALE: This report presents a unique case of a patient diagnosed with Primary Sjögren's syndrome and a relatively rare traditional Chinese medicine pattern, known as the combined cold and heat pattern and cold-dampness syndrome. The patient's condition was successfully managed using Chinese herbal medicine, specifically the modified Da-Chai-Hu decoction and Linggui Zhugan decoction. PATIENT CONCERNS: A 56-year-old woman had chronic dry eye and mouth for over 10 years. She was initially managed with traditional Chinese herbal medicine (TCHM) prescriptions, including the Zengye decoction, but the therapeutic effects were unsatisfactory. As the disease progressed, she was diagnosed with an anxiety disorder due to symptoms of vexation and insomnia. Treatment with alprazolam and venlafaxine failed to alleviate these symptoms. Recently, her general condition gradually worsened, with symptoms including a bitter taste in her mouth, dizziness, hot flashes, chills, poor appetite, chest discomfort, and constipation. DIAGNOSES: After a series of examinations, including a Schirmer test and labial gland biopsy, she was diagnosed with Sjögren's syndrome. INTERVENTIONS: Despite regular treatment with pilocarpine, sodium hyaluronate eye drops, venlafaxine, and alprazolam, the dry mouth symptoms intensified. Consequently, she sought further intervention through the TCHM. OUTCOMES: After 8 weeks of treatment with the modified Da-Chai-Hu decoction and Linggui Zhugan decoction, she reported a significant improvement in her dryness-related symptoms and sleep quality. LESSONS: This case report demonstrates that TCHM can effectively treat Primary Sjögren's syndrome, and should be considered for broader applications. Furthermore, this underscores the importance of tailoring treatment formulas to patients by identifying their specific syndrome differentiation in a clinical setting.


Assuntos
Medicamentos de Ervas Chinesas , Síndrome de Sjogren , Humanos , Feminino , Pessoa de Meia-Idade , Alprazolam , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Síndrome de Sjogren/complicações , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/tratamento farmacológico , Cloridrato de Venlafaxina
20.
ACS Appl Mater Interfaces ; 16(22): 28517-28525, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38769473

RESUMO

Effective catalytic performance of the transition metal oxide is attributed to high specific surface areas, abundant surface oxygen atoms, and balanced valence ratios. Although the chirality of the transition metal has attracted attention, most studies have focused on optical application. A few chiral transition metal oxides were used as electrocatalysts and photocatalysts. The influence of the chiral catalysts on the thermal catalysis process has been less explored. In this study, Mn-loaded chiral (M/l-CuO and M/d-CuO) and achiral CuO (M/a-CuO) were synthesized and compared in the catalytic oxidization of toluene. Spectrally analyzed Mn was well-dispersed on both chiral and achiral CuO. l-CuO and d-CuO showed nanoflower-like chirality. The angles between each (001) plane of CuO were the source of chirality. The toluene turnover frequency (TOF) of the samples was in the order of Mn/d-CuO (5.6 × 10-5 s-1) > Mn/l-CuO (4.4 × 10-5 s-1) > Mn/a-CuO (3.2 × 10-5 s-1) at 240 °C, consistent with the order of the oxygen replenishment rate. The as-prepared catalysts had similar ratios of lattice oxygen/surface adsorbed oxygen, Mn3+/Mn4+, and Cu+/Cu2+. A higher TOF was attributed to chirality, which increased the lattice oxygen replenishment speed from the gaseous phase to the solid surface. Our study indicates gas-solid catalysis from a structure-activity viewpoint.

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