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1.
Chin J Integr Med ; 30(4): 322-329, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37861963

RESUMO

OBJECTIVE: To investigate the mechanistic basis for the anti-proliferation and anti-invasion effect of tumor necrosis factor-related apoptosis-induced ligand (TRAIL) and celastrol combination treatment (TCCT) in glioblastoma cells. METHODS: Cell counting kit-8 was used to detect the effects of different concentrations of celastrol (0-16 µmol/L) and TRAIL (0-500 ng/mL) on the cell viability of glioblastoma cells. U87 cells were randomly divided into 4 groups, namely control, TRAIL (TRAIL 100 ng/mL), Cel (celastrol 0.5 µmol/L) and TCCT (TRAIL 100 ng/mL+ celastrol 0.5 µmol/L). Cell proliferation, migration, and invasion were detected by colony formation, wound healing, and Transwell assays, respectively. Quantitative reverse transcription polymerase chain reaction and Western blotting were performed to assess the levels of epithelial-mesenchymal transition (EMT) markers (zona occludens, N-cadherin, vimentin, zinc finger E-box-binding homeobox, Slug, and ß-catenin). Wnt pathway was activated by lithium chloride (LiCl, 20 mol/L) and the mechanism for action of TCCT was explored. RESULTS: Celastrol and TRAIL synergistically inhibited the proliferation, migration, invasion, and EMT of U87 cells (P<0.01). TCCT up-regulated the expression of GSK-3ß and down-regulated the expression of ß-catenin and its associated proteins (P<0.05 or P<0.01), including c-Myc, Cyclin-D1, and matrix metalloproteinase (MMP)-2. In addition, LiCl, an activator of the Wnt signaling pathway, restored the inhibitory effects of TCCT on the expression of ß-catenin and its downstream genes, as well as the migration and invasion of glioblastoma cells (P<0.05 or P<0.01). CONCLUSIONS: Celastrol and TRAIL can synergistically suppress glioblastoma cell migration, invasion, and EMT, potentially through inhibition of Wnt/ß-catenin pathway. This underlies a novel mechanism of action for TCCT as an effective therapy for glioblastoma.


Assuntos
Glioblastoma , Triterpenos Pentacíclicos , Via de Sinalização Wnt , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , beta Catenina/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Ligantes , Linhagem Celular Tumoral , Apoptose , Fatores de Necrose Tumoral/farmacologia , Proliferação de Células , Movimento Celular , Transição Epitelial-Mesenquimal
2.
Int J Mol Sci ; 24(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38069311

RESUMO

Although recent research progress on the abundant C-to-U RNA editing events in plant chloroplasts and mitochondria has uncovered many recognition factors and their molecular mechanisms, the intrinsic regulation of RNA editing within plants remains largely unknown. This study aimed to establish a regulatory relationship in Arabidopsis between the plant hormone auxin and chloroplast RNA editing. We first analyzed auxin response elements (AuxREs) present within promoters of chloroplast editing factors reported to date. We found that each has more than one AuxRE, suggesting a potential regulatory role of auxin in their expression. Further investigation unveiled that the depletion of auxin synthesis gene YUC2 reduces the expression of several editing factors. However, in yuc2 mutants, only the expression of CRR4, DYW1, ISE2, and ECD1 editing factors and the editing efficiency of their corresponding editing sites, ndhD-2 and rps14-149, were simultaneously suppressed. In addition, exogenous IAA and the overexpression of YUC2 enhanced the expression of these editing factors and the editing efficiency at the ndhD-2 and rps14-149 sites. These results suggested a direct effect of auxin upon the editing of the ndhD-2 and rps14-149 sites through the modulation of the expression of the editing factors. We further demonstrated that ARF1, a downstream transcription factor in the auxin-signaling pathway, could directly bind to and inactivate the promoters of CRR4, DYW1, and ISE2 in a dual-luciferase reporter system, thereby inhibiting their expression. Moreover, the overexpression of ARF1 in Arabidopsis significantly reduced the expression of the three editing factors and the editing efficiency at the ndhD-2 and rps14-149 sites. These data suggest that YUC2-mediated auxin biosynthesis governs the RNA-editing process through the ARF1-dependent signal transduction pathway.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Proteínas Ribossômicas/metabolismo , Edição de RNA , RNA de Cloroplastos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Viruses ; 15(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38140597

RESUMO

The adenovirus C5 E1B-55K protein is crucial for viral replication and is expressed early during infection. It can interact with E4orf6 to form a complex that functions as a ubiquitin E3 ligase. This complex targets specific cellular proteins and marks them for ubiquitination and, predominantly, subsequent proteasomal degradation. E1B-55K interacts with various proteins, with p53 being the most extensively studied, although identifying binding sites has been challenging. To explain the diverse range of proteins associated with E1B-55K, we hypothesized that other binding partners might recognize the simple p53 binding motif (xWxxxPx). In silico analyses showed that many known E1B-55K binding proteins possess this amino acid sequence; therefore, we investigated whether other xWxxxPx-containing proteins also bind to E1B-55K. Our findings revealed that many cellular proteins, including ATR, CHK1, USP9, and USP34, co-immunoprecipitate with E1B-55K. During adenovirus infection, several well-characterized E1B-55K binding proteins and newly identified interactors, including CSB, CHK1, and USP9, are degraded in a cullin-dependent manner. Notably, certain binding proteins, such as ATR and USP34, remain undegraded during infection. Structural predictions indicate no conservation of structure around the proposed binding motif, suggesting that the interaction relies on the correct arrangement of tryptophan and proline residues.


Assuntos
Infecções por Adenoviridae , Proteínas E4 de Adenovirus , Adenovírus Humanos , Humanos , Adenoviridae/metabolismo , Proteínas E1B de Adenovirus/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Infecções por Adenoviridae/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas E4 de Adenovirus/genética , Proteínas E4 de Adenovirus/metabolismo , Adenovírus Humanos/genética , Adenovírus Humanos/metabolismo
4.
Hum Reprod ; 38(9): 1761-1768, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37403336

RESUMO

STUDY QUESTION: Does a public online IVF success prediction calculator based on real-world data help set patient expectations? SUMMARY ANSWER: The YourIVFSuccess Estimator aided consumer expectations of IVF success: one quarter (24%) of participants were unsure of their estimated IVF success before using the tool; one half changed their prediction of success after using the tool and one quarter (26%) had their expectations of IVF success confirmed. WHAT IS KNOWN ALREADY: Several web-based IVF prediction tools exist worldwide but have not been evaluated for their impact on patient expectations, nor for patient perceptions of usefulness and trustworthiness. STUDY DESIGN, SIZE, DURATION: This is a pre-post evaluation of a convenience sample of 780 online users of the Australian YourIVFSuccess Estimatorhttps://yourivfsuccess.com.au/ between 1 July and 31 November 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were eligible if they were over 18 years of age, Australian residents, and considering IVF for themselves or their partner. Participants filled in online surveys before and after using the YourIVFSuccess Estimator. MAIN RESULTS AND THE ROLE OF CHANCE: The response rate of participants who completed both surveys and the YourIVFSuccess Estimator was 56% (n = 439). The YourIVFSuccess Estimator aided consumer expectations of IVF success: one quarter (24%) of participants were unsure of their estimated IVF success before using the tool; one half changed their prediction of success after using the tool (20% increased, 30% decreased), bringing their predictions in line with the YourIVFSuccess Estimator, and one quarter (26%) had their IVF success expectations confirmed. One in five participants claimed they would change the timing of IVF treatment. The majority of participants found the tool to be at least moderately trustworthy (91%), applicable (82%), and helpful (80%), and would recommend it to others (60%). The main reasons given for the positive responses were that the tool is independent (government funded, academic) and based on real-world data. Those who did not find it applicable or helpful were more likely to have had a worse-than-expected prediction, or to have experienced non-medical infertility (e.g. single women, LGBTQIA+), noting that at the time of evaluation the Estimator did not accommodate these patient groups. LIMITATIONS, REASONS FOR CAUTION: Those who dropped out between the pre- and post-surveys tended to have a lower education status or have been born outside of Australia or New Zealand, therefore there may be issues with generalizability. WIDER IMPLICATIONS OF THE FINDINGS: With consumers demanding increasing levels of transparency and participation in decisions around their medical care, public-facing IVF predictor tools based on real-world data are useful for aligning expectations about IVF success rates. Given differences in patient characteristics and IVF practices internationally, national data sources should be used to inform country-specific IVF prediction tools. STUDY FUNDING/COMPETING INTEREST(S): The YourIVFSuccess website and evaluation of the YourIVFSuccess Estimator are supported by the Medical Research Future Fund (MRFF) Emerging Priorities and Consumer Driven Research initiative: EPCD000007. BKB, ND, and OF have no conflicts to declare. DM holds a clinical role at Virtus Health. His role did not influence the analysis plan or interpretation of results in this study. GMC is an employee of the UNSW Sydney, and Director of the UNSW NPESU. UNSW receives research funding on behalf of Prof Chambers from the MRFF to develop and manage the Your IVF Success website. Grant ID: MRFF Emerging Priorities and Consumer Driven Research initiative: EPCD000007. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Infertilidade , Motivação , Gravidez , Humanos , Feminino , Adolescente , Adulto , Austrália , Infertilidade/terapia , Parto , Fertilização in vitro
5.
Plant Sci ; 334: 111751, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37263527

RESUMO

The Arabidopsis pentatricopeptide repeat (PPR) proteins, required for accD RNA editing 1 (RARE1) and early chloroplast biogenesis 2 (AtECB2), each contain a DYW domain deemed essential for cytosine deamination at the accD-C794 RNA editing site in chloroplasts. Complementation assays using the rare1 mutant investigate the correlation between these PPRs and their respective DYW domain functions in RNA editing of accD-C794. The results demonstrate that the coding sequence of AtECB2 cannot replace that of RARE1. Moreover, rare1 mutants complemented with DYW-deleted RARE1 failed to recover the RNA editing of accD-C794 even in the presence of the highly similar DYW domain of the AtECB2 protein. These findings indicate that RARE1 and AtECB2 possess divergent roles in RNA editing, with specificity for accD-C794 directly attributable to DYW domain within RARE1. Structural modeling data suggest this functioning pertains to a local α-helical motif that residues slightly N-terminal to the consensus glutamate and CXXCH motif in the DYW domain for cytidine deamination during C-to-U editing by RARE1 that is absent within AtECB2.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , Edição de RNA , Acetil-CoA Carboxilase/metabolismo
6.
Genes Dis ; 10(1): 284-300, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37013063

RESUMO

Osteoporosis (OP) is a debilitating skeletal abnormality involving bone remodeling and bone cell homeostasis characterized by decreased bone strength and high fracture risk. A novel therapeutic intervention for OP by manipulating cellular autophagy-apoptosis processes to promote skeletal homeostasis is presented. Protective effects of the naturally occurring plant extract Liquiritigenin (LG) were demonstrated in an ovariectomy (OVX)-OP mouse model and preosteoblast MC3T3-E1 cells. Micro-CT and histological staining assessments of skeletal phenotype were applied alongside detection of autophagy activity in osteocytes and MC3T3-E1 cells by transmission electron microscopy (TEM). The effects of LG on chloroquine (CQ)- and the apoptosis-inducing TS-treated osteogenic differentiations and status of lysosomes within MC3T3-E1 cells were analyzed by Neutral red, Alizarin red S and alkaline phosphatase (ALP) staining and Western blot assays. Treatment with LG prevented bone loss, increased osteogenic differentiation in vivo and in vitro, and inhibited osteoclast formation to some extent. TEM analyses revealed that LG can improve auto-lysosomal degradation within osteocytes from OVX mice and MC3T3-E1 cells. The abnormal status of lysosomes associated with CQ and TS treatments was notably alleviated by LG which also reduced levels of apoptosis-induced inhibition of osteogenic differentiation and averted abnormal osteogenic differentiation as a consequence of a blockage in autolysosome degradation. Overall, LG stimulates bone growth in OVX mice through increased osteogenic differentiation and regulation of autophagy-apoptosis mechanisms, presenting an auspicious natural therapy for OP.

7.
Plant Commun ; 4(1): 100461, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221851

RESUMO

It has been reported that Arabidopsis chloroplast accD transcripts undergo RNA editing and that loss of accD-C794 RNA editing does not affect plant growth under normal conditions. To date, the exact biological role of accD-C794 editing has remained elusive. Here, we reveal an unexpected role for accD-C794 editing in response to heat stress. Loss of accD-C794 editing results in a yellow and dwarf phenotype with decreased chloroplast gene expression under heat stress, and artificial improvement of C794-edited accD gene expression enhances heat tolerance in Arabidopsis. These data suggest that accD-C794 editing confers heat tolerance in planta. We also found that treatment with the product of acetyl coenzyme A carboxylase (ACCase) could allay mutant phenotypic characteristics and showed that a mutation in the CAC3 gene for the α-subunit of ACCase was associated with dwarfism under heat stress. These observations indicate that defective accD-C794 editing may be intrinsic to reduced ACCase activity, thereby contributing to heat sensitivity. ACCase catalyzes the committed step of de novo fatty acid (FA) biosynthesis. FA content analysis revealed that unsaturated oleic (C18:1) and linoleic acids (C18:2) were low in the accD-C794 editing-defective mutant but high in the C794-edited accD-overexpressing plants compared with the wild type. Supplying exogenous C18:1 and C18:2 could rescue the mutant phenotype, suggesting that these FAs play an essential role in tolerance to heat stress. Transmission electron microscopy observations showed that heat stress seriously affected the membrane architecture in accD editing-defective mutants but not in accD-overexpressing plants. These results provide the first evidence that accD-C794 editing regulates FA biosynthesis for maintenance of membrane structural homeostasis under heat stress.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Ligação a RNA , Termotolerância , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Termotolerância/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
8.
Alzheimer Dis Assoc Disord ; 36(3): 269-271, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36001766

RESUMO

BACKGROUND: Alzheimer disease (AD) patients experience progressive neurological and cognitive decline attributed to neurodegeneration. Cerebral dopamine neurotrophic factor (CDNF) has been identified to protect and rescue neurons in various preclinical neurodegeneration models. The expression of this protein occurs in both the central nervous system and peripheral blood. Blood platelets exhibit several biochemical impairments similar to the brain tissues of patients with neurological disorders. This study examines CDNF mRNA expression in human blood platelets in healthy subjects and Alzheimer-probable patients. METHODS: Platelets were extracted from whole blood from patients. mRNA was extracted to synthesize cDNA and quantify CDNF gene expression from 21 Alzheimer-probable patients and 73 healthy age-matched control subjects using real-time qPCR. Grouping analysis of the data with regard to sex was conducted. RESULTS: CDNF mRNA expression was significantly decreased in Alzheimer-probable patients relative to the control subjects (P<0.05). Further analysis demonstrated reduced CDNF expression in male Alzheimer-probable patients compared with their age and sex-matched controls (P<0.05). However, no change in female subjects was observed. Interestingly, there is a lower level of CDNF expression in the female control group relative to the control male group (P<0.05). CONCLUSION: Alzheimer-probable male patients demonstrated significant reductions in CDNF expression, suggesting that CDNF plays a significant role in the pathogenesis of AD. In addition, it may assist in diagnosing male Alzheimer patients.


Assuntos
Doença de Alzheimer , Fatores de Crescimento Neural , Doença de Alzheimer/genética , Plaquetas/metabolismo , Dopamina , Feminino , Humanos , Masculino , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , RNA Mensageiro/genética
9.
BMC Med Imaging ; 22(1): 125, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35836141

RESUMO

BACKGROUND: Malignant 'triton' tumor is an extremely rare subtype of malignant periphery nerve sheath tumors. Clinical diagnosis of malignant triton tumor is difficult before surgery due to its low incidence and the lack of knowledge. Therefore, to describe and summarize the CT imaging characteristics of malignant triton tumor is of great assistance for early and preoperative diagnosis. CASE PRESENTATION: Two cases suspected of MTT by CT scan before operation were closely observed. The diagnosis of malignant triton tumor was eventually confirmed by immunochemical assay, which verified speculation of CT scans. Huge, irregular, well-circumscribed lobulated mass-like shadows can be observed from these patients by CT scans. Besides, heterogeneity of density within the body of tumor was well-established by CT scans, together with linear septum. Meanwhile, CT scans demonstrated that calcifications were remarkable at the margin of tumor body. CONCLUSIONS: Some CT image features from two cases were presented as a reference for the preoperative consideration of MTT: (i) enormity of mass-like shadow; (ii) presence of well-circumscribed lobulated shape; (iii) septum within the well-defined mass accompanied with hemorrhage, necrosis and cystic changes as well as calcification, especially within neurofibromatosis type 1 patients.


Assuntos
Neoplasias Ósseas , Neoplasias da Mama , Feminino , Humanos , Tomografia Computadorizada por Raios X
10.
Artigo em Inglês | MEDLINE | ID: mdl-35162397

RESUMO

BACKGROUND: Prompt and efficient identification and stratification of patients who are frail is important, as this cohort are at high risk of adverse healthcare outcomes. Numerous frailty screening tools have been developed to support their identification across different settings, yet relatively few have emerged for use in emergency departments (EDs). This protocol provides details for a systematic review aiming to synthesize the accumulated evidence regarding the diagnostic accuracy and clinimetric properties of frailty screening instruments to identify frail older adults in EDs. METHODS: Six electronic databases will be searched from January 2000 to March 2021. Eligible studies will include adults aged ≥60 years screened in EDs with any available screening instrument to identify frailty (even if not originally designed for this purpose). Studies, including case-control, longitudinal, and cohort studies, will be included, where instruments are compared to a reference standard to explore diagnostic accuracy. Predictive accuracy for a selection of outcomes, including mortality, institutionalization, and readmission, will be assessed. Clinical and methodological heterogeneity will be examined, and a random effects meta-analysis performed if appropriate. CONCLUSION: Understanding whether frailty screening on presentation to EDs is accurate in identifying frailty, and predicting these outcomes is important for decision-making and targeting appropriate management.


Assuntos
Idoso Fragilizado , Fragilidade , Idoso , Serviço Hospitalar de Emergência , Fragilidade/diagnóstico , Avaliação Geriátrica/métodos , Humanos , Programas de Rastreamento , Metanálise como Assunto , Pessoa de Meia-Idade , Revisões Sistemáticas como Assunto
11.
Clin Gerontol ; 45(3): 525-537, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32065071

RESUMO

Objectives: Brief screening instruments are useful in busy clinical practice to identify those requiring further assessment. This study aims to translate and validate a Portuguese version of the four-item Zarit Burden Interview (ZBI-4) to identify caregiver burden in a community-based sample in Northern Portugal.Methods: We collected data from 203 informal caregivers of community-dwellers aged ≥80 years. Internal consistency and factors were measured using Cronbach's alpha. Pearson's correlation was used to examine construct validity against negative and positive aspects of caregiving from the Caregiving Appraisal Scale. Discriminative ability was evaluated from the area under the receiver operating characteristic curve (AUC). Optimal cutoffs were calculated using Youden´s Index.Results: The internal consistency of the Portuguese version of the ZBI-4 was good (alpha = 0.71). Concurrent validity was acceptable, showing strong correlation with the negative (rho = 0.66) and medium correlation with positive (rho = -0.33) aspects of the Caregiving Appraisal Scale. Discriminative accuracy for caregiver burden was also good (AUC = 0.86). Youden's index produced an optimal cutoff of ≥7 points for burden.Conclusions: The Portuguese version of the ZBI-4 screen demonstrates good psychometric properties.Clinical implications: These results show the utility of the Portuguese version of ZBI-4 as a short screen for caregiver burden for use in the community to facilitate rapid screening for this important and complex stressor.


Assuntos
Sobrecarga do Cuidador , Cuidadores , Humanos , Portugal , Psicometria , Reprodutibilidade dos Testes
12.
Crit Care Med ; 50(4): 674-684, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34582411

RESUMO

OBJECTIVES: Sepsis remains a highly lethal disease, whereas the precise reasons for death remain poorly understood. Prokineticin2 is a secreted protein that regulates diverse biological processes. Whether prokineticin2 is beneficial or deleterious to sepsis and the underlying mechanisms remain unknown. DESIGN: Prospective randomized animal investigation and in vitro studies. SETTING: Research laboratory at a medical university hospital. SUBJECTS: Prokineticin2 deficiency and wild-type C57BL/6 mice were used for in vivo studies; sepsis patients by Sepsis-3 definitions, patient controls, and healthy controls were used to obtain blood for in vitro studies. INTERVENTIONS: Prokineticin2 concentrations were measured and analyzed in human septic patients, patient controls, and healthy individuals. The effects of prokineticin2 on sepsis-related survival, bacterial burden, organ injury, and inflammation were assessed in an animal model of cecal ligation and puncture-induced polymicrobial sepsis. In vitro cell models were also used to study the role of prokineticin2 on antibacterial response of macrophages. MEASUREMENTS AND MAIN RESULTS: Prokineticin2 concentration is dramatically decreased in the patients with sepsis and septic shock compared with those of patient controls and healthy controls. Furthermore, the prokineticin2 concentration in these patients died of sepsis or septic shock is significantly lower than those survival patients with sepsis or septic shock, indicating the potential value of prokineticin2 in the diagnosis of sepsis and septic shock, as well as the potential value in predicting mortality in adult patients with sepsis and septic shock. In animal model, recombinant prokineticin2 administration protected against sepsis-related deaths in both heterozygous prokineticin2 deficient mice and wild-type mice and alleviated sepsis-induced multiple organ damage. In in vitro cell models, prokineticin2 enhanced the phagocytic and bactericidal functions of macrophage through signal transducers and activators of transcription 3 pathway which could be abolished by signal transducers and activators of transcription 3 inhibitors S3I-201. Depletion of macrophages reversed prokineticin2-mediated protection against polymicrobial sepsis. CONCLUSIONS: This study elucidated a previously unrecognized role of prokineticin2 in clinical diagnosis and treatment of sepsis. The proof-of-concept study determined a central role of prokineticin2 in alleviating sepsis-induced death by regulation of macrophage function, which presents a new strategy for sepsis immunotherapy.


Assuntos
Sepse , Choque Séptico , Animais , Modelos Animais de Doenças , Humanos , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Estudos Prospectivos
13.
J Biol Chem ; 297(5): 101234, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34562453

RESUMO

Juvenile hormone (JH) acid methyltransferase (JHAMT) is a rate-limiting enzyme that converts JH acids or inactive precursors of JHs to active JHs at the final step of JH biosynthesis in insects and thus presents an excellent target for the development of insect growth regulators or insecticides. However, the three-dimensional properties and catalytic mechanism of this enzyme are not known. Herein, we report the crystal structure of the JHAMT apoenzyme, the three-dimensional holoprotein in binary complex with its cofactor S-adenosyl-l-homocysteine, and the ternary complex with S-adenosyl-l-homocysteine and its substrate methyl farnesoate. These structures reveal the ultrafine definition of the binding patterns for JHAMT with its substrate/cofactor. Comparative structural analyses led to novel findings concerning the structural specificity of the progressive conformational changes required for binding interactions that are induced in the presence of cofactor and substrate. Importantly, structural and biochemical analyses enabled identification of one strictly conserved catalytic Gln/His pair within JHAMTs required for catalysis and further provide a molecular basis for substrate recognition and the catalytic mechanism of JHAMTs. These findings lay the foundation for the mechanistic understanding of JH biosynthesis by JHAMTs and provide a rational framework for the discovery and development of specific JHAMT inhibitors as insect growth regulators or insecticides.


Assuntos
Bombyx/enzimologia , Proteínas de Insetos/química , Hormônios Juvenis/química , Metiltransferases/química , Animais , Bombyx/genética , Cristalografia por Raios X , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Hormônios Juvenis/biossíntese , Hormônios Juvenis/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Domínios Proteicos
14.
Artigo em Inglês | MEDLINE | ID: mdl-34444331

RESUMO

Brief cognitive screening instruments are used to identify patients presenting with cognitive symptoms that warrant further assessment. This study aimed to evaluate the reliability and validity of the Persian version of the Quick Mild Cognitive Impairment (Qmci-Pr) among middle-aged and older Iranian adults. Consecutive patients aged ≥55 years and caregivers attending with them as normal controls (NCs) were recruited from geriatric outpatient clinics and a hospital in Tehran, Iran. All patients completed the Qmci-Pr before completing an independent detailed neuropsychological assessment and staging using the Clinical Dementia Rating (CDR) Scale. NCs underwent the same assessment. In all, 92 participants with a median age of 70 years (±13) were available. Of these, 20 participants were NCs, 24 had subjective memory complaints (SMC), 24 had mild cognitive impairment (MCI), and 24 had Alzheimer's disease (AD). The Qmci-Pr had good accuracy in differentiating SMC and NC from MCI (area under the curve (AUC): 0.80 (0.69-0.91)) and in identifying cognitive impairment (MCI and mild AD) (AUC: 0.87 (0.80-0.95)) with a sensitivity of 88% and specificity of 80%, at an optimal cut-off of <53/100. The Qmci-Pr is an accurate short cognitive screening impairment for separating NC and patients with SMC from MCI and identifying cognitive impairment. Further research with larger samples and comparison with other widely used instruments such as the Montreal Cognitive Assessment is needed. Given its established brevity, the Qmci-Pr is a useful screen for Iranian adults across the spectrum of cognitive decline.


Assuntos
Disfunção Cognitiva , Demência , Adulto , Idoso , Disfunção Cognitiva/diagnóstico , Humanos , Irã (Geográfico) , Pessoa de Meia-Idade , Testes Neuropsicológicos , Psicometria , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Prim Health Care Res Dev ; 21: e32, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32928334

RESUMO

Non-communicable chronic diseases (NCCDs) are the main cause of morbidity and mortality globally. Demographic aging has resulted in older populations with more complex healthcare needs. This necessitates a multilevel rethinking of healthcare policies, health education and community support systems with digitalization of technologies playing a central role. The European Innovation Partnership on Active and Healthy Aging (A3) working group focuses on well-being for older adults, with an emphasis on quality of life and healthy aging. A subgroup of A3, including multidisciplinary stakeholders in health care across Europe, focuses on the palliative care (PC) model as a paradigm to be modified to meet the needs of older persons with NCCDs. This development paper delineates the key parameters we identified as critical in creating a public health model of PC directed to the needs of persons with NCCDs. This paradigm shift should affect horizontal components of public health models. Furthermore, our model includes vertical components often neglected, such as nutrition, resilience, well-being and leisure activities. The main enablers identified are information and communication technologies, education and training programs, communities of compassion, twinning activities, promoting research and increasing awareness amongst policymakers. We also identified key 'bottlenecks': inequity of access, insufficient research, inadequate development of advance care planning and a lack of co-creation of relevant technologies and shared decision-making. Rethinking PC within a public health context must focus on developing policies, training and technologies to enhance person-centered quality life for those with NCCD, while ensuring that they and those important to them experience death with dignity.


Assuntos
Doenças não Transmissíveis , Cuidados Paliativos , Europa (Continente) , Humanos , Saúde Pública , Qualidade de Vida
17.
J Virol ; 94(21)2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32847858

RESUMO

It has long been established that group A human adenoviruses (HAdV-A12, -A18, and -A31) can cause tumors in newborn rodents, with tumorigenicity related to the presence of a unique spacer region located between conserved regions 2 and 3 within the HAdV-A12 early region 1A (E1A) protein. Group B adenoviruses are weakly oncogenic, whereas most of the remaining human adenoviruses are nononcogenic. In an attempt to understand better the relationship between the structure of the AdE1A spacer region and oncogenicity of HAdVs, the structures of synthetic peptides identical or very similar to the adenovirus 12 E1A spacer region were determined and found to be α-helical using nuclear magnetic resonance (NMR) spectroscopy. This contrasts significantly with some previous suggestions that this region is unstructured. Using available predictive algorithms, the structures of spacer regions from other E1As were also examined, and the extent of the predicted α-helix was found to correlate reasonably well with the tumorigenicity of the respective virus. We suggest that this may represent an as-yet-unknown binding site for a partner protein required for tumorigenesis.IMPORTANCE This research analyzed small peptides equivalent to a region within the human adenovirus early region 1A protein that confers, in part, tumor-inducing properties to various degrees on several viral strains in rats and mice. The oncogenic spacer region is α-helical, which contrasts with previous suggestions that this region is unstructured. The helix is characterized by a stretch of amino acids rich in alanine residues that are organized into a hydrophobic, or "water-hating," surface that is considered to form a major site of interaction with cellular protein targets that mediate tumor formation. The extent of α-helix in E1A from other adenovirus species can be correlated to a limited degree to the tumorigenicity of that virus. Some serotypes show significant differences in predicted structural propensity, suggesting that the amino acid type and physicochemical properties are also of importance.


Assuntos
Adenovírus Humanos/genética , Adenovírus Humanos/patogenicidade , Carcinogênese/genética , DNA Intergênico/genética , Peptídeos/química , Adenovírus Humanos/metabolismo , Motivos de Aminoácidos , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , DNA Intergênico/química , DNA Intergênico/metabolismo , Células Eucarióticas/patologia , Células Eucarióticas/virologia , Interações Hospedeiro-Patógeno/genética , Humanos , Camundongos , Modelos Moleculares , Mutação , Ressonância Magnética Nuclear Biomolecular , Peptídeos/genética , Peptídeos/metabolismo , Biossíntese de Proteínas , Conformação Proteica em alfa-Hélice , Ratos , Sorogrupo , Relação Estrutura-Atividade
18.
Alzheimer Dis Assoc Disord ; 34(4): 350-356, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32530832

RESUMO

BACKGROUND: Cutoff values of cognitive screen tests vary according to age and educational levels. OBJECTIVE: The objective of this study was to compare the accuracy and determine cutoffs for 3 short cognitive screening instruments: the Mini-Mental State Examination, Montreal Cognitive Assessment (MoCA), and Quick Mild Cognitive Impairment Screen-Turkish version (Qmci-TR), in older adults with low literacy in Turkey. METHODS: In all 321 patients, 133 with subjective cognitive complaints (SCC), 88 amnestic-type mild cognitive impairment (aMCI), and 100 with probable Alzheimer disease (AD) with a median of 5 years education were included. Education and age-specific cutoffs were determined. RESULTS: For the overall population, the Qmci-TR was more accurate than the MoCA in distinguishing between aMCI and AD (area under the curve=0.83 vs. 0.76, P=0.004) and the Qmci-TR and Mini-Mental State Examination were superior to the MoCA in discriminating SCC from aMCI and AD. All instruments had similar accuracy among those with low literacy (primary school and lower educational level or illiterate). CONCLUSIONS: To distinguish between SCC, aMCI, and AD in a sample of older Turkish adults, the Qmci-TR may be preferable. In very low literacy, the choice of the instrument appears less important.


Assuntos
Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Alfabetização , Programas de Rastreamento , Testes de Estado Mental e Demência/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Escolaridade , Feminino , Humanos , Masculino , Turquia
19.
Plant Sci ; 278: 64-69, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30471730

RESUMO

RNA editing in chloroplasts and mitochondria is performed by hypothetical editosomes. The MORF family proteins are essential components of these editosomes. In Arabidopsis, MORF2 and MORF9 are involved in the editing of most sites in chloroplasts. In this work, we performed immunoprecipitation and mass spectrometry assays of transgenic lines expressing MORF2-4xMYC and MORF9-4xMYC to identify interacting proteins. We found that MORF2 and MORF9 are present in the same complex. Blue-Native PAGE analysis of chloroplast protein complexes also revealed that both MORF2 and MORF9 are part of a complex of approximately 140 kDa, suggesting the existence of tight MORF2-MORF9 interaction in chloroplasts. The editing of ndhD-1 (ndhD-C2) site was reported to be blocked in both morf2 and morf9. RNA immunoprecipitation assays showed that MORF2 and MORF9 are tightly associated with the editing site of ndhD-1. However, in an RNA-EMSA assay MORF2 and MORF9 could not directly bind to transcripts harboring the editing site of ndhD-1. Taken together, these results indicate that the MORF2-MORF9 heterodimer is the core members of editosomes in chloroplasts, while they are not responsible for RNA editing site recognition.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/genética , Cloroplastos/genética , Proteínas Mitocondriais/fisiologia , Edição de RNA , Proteínas de Ligação a RNA/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Eletroforese em Gel de Poliacrilamida , Imunoprecipitação , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Plantas Geneticamente Modificadas/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
20.
Aust N Z J Obstet Gynaecol ; 58(6): E33-E34, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30536517
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