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1.
Proc Natl Acad Sci U S A ; 120(22): e2300282120, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37216560

RESUMO

In actinobacteria, an OmpR/PhoB subfamily protein called GlnR acts as an orphan response regulator and globally coordinates the expression of genes responsible for nitrogen, carbon, and phosphate metabolism in actinobacteria. Although many researchers have attempted to elucidate the mechanisms of GlnR-dependent transcription activation, progress is impeded by lacking of an overall structure of GlnR-dependent transcription activation complex (GlnR-TAC). Here, we report a co-crystal structure of the C-terminal DNA-binding domain of GlnR (GlnR_DBD) in complex with its regulatory cis-element DNA and a cryo-EM structure of GlnR-TAC which comprises Mycobacterium tuberculosis RNA polymerase, GlnR, and a promoter containing four well-characterized conserved GlnR binding sites. These structures illustrate how four GlnR protomers coordinate to engage promoter DNA in a head-to-tail manner, with four N-terminal receiver domains of GlnR (GlnR-RECs) bridging GlnR_DBDs and the RNAP core enzyme. Structural analysis also unravels that GlnR-TAC is stabilized by complex protein-protein interactions between GlnR and the conserved ß flap, σAR4, αCTD, and αNTD domains of RNAP, which are further confirmed by our biochemical assays. Taken together, these results reveal a global transcription activation mechanism for the master regulator GlnR and other OmpR/PhoB subfamily proteins and present a unique mode of bacterial transcription regulation.


Assuntos
Actinobacteria , Actinobacteria/genética , Actinobacteria/metabolismo , Ativação Transcricional/genética , Proteínas de Bactérias/metabolismo , Transativadores/metabolismo , Regiões Promotoras Genéticas/genética , Regulação Bacteriana da Expressão Gênica
2.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38012122

RESUMO

Mild cognitive impairment is considered the prodromal stage of Alzheimer's disease. Accurate diagnosis and the exploration of the pathological mechanism of mild cognitive impairment are extremely valuable for targeted Alzheimer's disease prevention and early intervention. In all, 100 mild cognitive impairment patients and 86 normal controls were recruited in this study. We innovatively constructed the individual morphological brain networks and derived multiple brain connectome features based on 3D-T1 structural magnetic resonance imaging with the Jensen-Shannon divergence similarity estimation method. Our results showed that the most distinguishing morphological brain connectome features in mild cognitive impairment patients were consensus connections and nodal graph metrics, mainly located in the frontal, occipital, limbic lobes, and subcortical gray matter nuclei, corresponding to the default mode network. Topological properties analysis revealed that mild cognitive impairment patients exhibited compensatory changes in the frontal lobe, while abnormal cortical-subcortical circuits associated with cognition were present. Moreover, the combination of multidimensional brain connectome features using multiple kernel-support vector machine achieved the best classification performance in distinguishing mild cognitive impairment patients and normal controls, with an accuracy of 84.21%. Therefore, our findings are of significant importance for developing potential brain imaging biomarkers for early detection of Alzheimer's disease and understanding the neuroimaging mechanisms of the disease.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Conectoma , Humanos , Conectoma/métodos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Imageamento por Ressonância Magnética/métodos
3.
J Chem Inf Model ; 64(14): 5413-5426, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38958413

RESUMO

In drug discovery, molecular docking methods face challenges in accurately predicting energy. Scoring functions used in molecular docking often fail to simulate complex protein-ligand interactions fully and accurately leading to biases and inaccuracies in virtual screening and target predictions. We introduce the "Docking Score ML", developed from an analysis of over 200,000 docked complexes from 155 known targets for cancer treatments. The scoring functions used are founded on bioactivity data sourced from ChEMBL and have been fine-tuned using both supervised machine learning and deep learning techniques. We validated our approach extensively using multiple data sets such as validation of selectivity mechanism, the DUDE, DUD-AD, and LIT-PCBA data sets, and performed a multitarget analysis on drugs like sunitinib. To enhance prediction accuracy, feature fusion techniques were explored. By merging the capabilities of the Graph Convolutional Network (GCN) with multiple docking functions, our results indicated a clear superiority of our methodologies over conventional approaches. These advantages demonstrate that Docking Score ML is an efficient and accurate tool for virtual screening and reverse docking.


Assuntos
Aprendizado de Máquina , Simulação de Acoplamento Molecular , Ligantes , Humanos , Descoberta de Drogas/métodos , Proteínas/química , Proteínas/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo , Interface Usuário-Computador
4.
Fungal Genet Biol ; 164: 103751, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36375736

RESUMO

Invasive Aspergillus fumigatus infection is a disease with high morbidity and mortality rates. Abnormalities in sporulation and pigmentation can significantly alter the pathogenicity of A. fumigatus, thus the mechanisms of conidiation and pigment biosynthesis have gained increasing attention. In Aspergillus oryzae, a novel predicted bHLH protein-encoding gene, ecdR, plays a role in asexual development, and its ortholog has also been characterized in A. nidulans. Herein, we determined its role in A. fumigatus by testing whether ecdR deletion affects asexual development, melanin synthesis, and regulation of virulence in this fungus. Our study shows that EcdR controls conidia and melanin production in A. fumigatus. In addition, we found that virulence in the ΔecdR strain was significantly reduced in the infection model of immunodeficiency mice.


Assuntos
Aspergillus fumigatus , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Animais , Camundongos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Virulência/genética , Esporos Fúngicos/genética , Proteínas Fúngicas/genética , Melaninas/genética , Pigmentação/genética
5.
Semin Dial ; 36(6): 454-461, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36726291

RESUMO

INTRODUCTION: Arteriovenous fistula or arteriovenous graft is essential to long-term survival and quality of life in patients receiving hemodialysis. To date, no research has examined the clinical impacts of different puncture methods. This study compared the rope ladder and area puncture techniques in terms of vascular patency, pain, and quality of life among patients receiving hemodialysis. METHODS: A prospective longitudinal study was performed with 6-month follow-up. A total of 98 participants recruited from a hemodialysis center in Taiwan were randomly assigned to receive the rope ladder technique (experimental group) or the area puncture technique (control group). Vascular patency was assessed by examining access flow and percutaneous transluminal angioplasty rate. Pain and quality of life were measured using the Numerical Pain Rating Scale (NPRS) and Kidney Disease Quality of Life Instrument (KDQOL-36™), respectively. All outcome variables were measured repeatedly and analyzed using a generalized estimating equation. RESULTS: Overall, quality of life was significantly better for the experimental group than for the control group (ß = 47.23, p < 0.001). The percutaneous transluminal angioplasty rate was lower for the experimental group than for the control group (12.0% vs. 18.8%). However, no significant differences were found in access flow and pain level between the two groups over time. CONCLUSION: Hemodialysis patients who received the rope ladder puncture technique had a lower percutaneous angioplasty rate and better quality of life than patients who received the area puncture technique, suggesting that the rope ladder technique could be implemented as a routine cannulation method in hemodialysis clinics.


Assuntos
Derivação Arteriovenosa Cirúrgica , Diálise Renal , Humanos , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Qualidade de Vida , Estudos Longitudinais , Estudos Prospectivos , Grau de Desobstrução Vascular , Punções , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Dor , Resultado do Tratamento , Oclusão de Enxerto Vascular
6.
Proc Natl Acad Sci U S A ; 117(3): 1711-1721, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31811023

RESUMO

Drug resistance in fungal pathogens has risen steadily over the past decades due to long-term azole therapy or triazole usage in agriculture. Modification of the drug target protein to prevent drug binding is a major recognized route to induce drug resistance. However, mechanisms for nondrug target-induced resistance remain only loosely defined. Here, we explore the molecular mechanisms of multidrug resistance resulted from an efficient adaptation strategy for survival in drug environments in the human pathogen Aspergillus fumigatus We show that mutants conferring multidrug resistance are linked with mitochondrial dysfunction induced by defects in heme A biosynthesis. Comparison of the gene expression profiles between the drug-resistant mutants and the parental wild-type strain shows that multidrug-resistant transporters, chitin synthases, and calcium-signaling-related genes are significantly up-regulated, while scavenging mitochondrial reactive oxygen species (ROS)-related genes are significantly down-regulated. The up-regulated-expression genes share consensus calcium-dependent serine threonine phosphatase-dependent response elements (the binding sites of calcium-signaling transcription factor CrzA). Accordingly, drug-resistant mutants show enhanced cytosolic Ca2+ transients and persistent nuclear localization of CrzA. In comparison, calcium chelators significantly restore drug susceptibility and increase azole efficacy either in laboratory-derived or in clinic-isolated A. fumigatus strains. Thus, the mitochondrial dysfunction as a fitness cost can trigger calcium signaling and, therefore, globally up-regulate a series of embedding calcineurin-dependent-response-element genes, leading to antifungal resistance. These findings illuminate how fitness cost affects drug resistance and suggest that disruption of calcium signaling might be a promising therapeutic strategy to fight against nondrug target-induced drug resistance.


Assuntos
Aspergillus fumigatus/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Farmacorresistência Fúngica/efeitos dos fármacos , Farmacorresistência Fúngica/fisiologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , Alquil e Aril Transferases/genética , Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Quelantes de Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Quitina Sintase/genética , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Heme/análogos & derivados , Heme/biossíntese , Humanos , Proteínas de Membrana/genética , Mitocôndrias/genética , Doenças Mitocondriais/genética , Fosfoproteínas Fosfatases/metabolismo , Espécies Reativas de Oxigênio , Fatores de Transcrição/metabolismo , Triazóis/farmacologia
7.
Entropy (Basel) ; 25(7)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37510021

RESUMO

In this paper, we investigate an uncertainty diagram and Kirkwood-Dirac (KD) nonclassicality based on discrete Fourier transform (DFT) in a d-dimensional system. We first consider the uncertainty diagram of the DFT matrix, which is a transition matrix from basis A to basis B. Here, the bases A, B are not necessarily completely incompatible. We show that for the uncertainty diagram of the DFT matrix, there is no "hole" in the region of the (nA,nB) plane above and on the line nA+nB=d+1. Then, we present where the holes are in the region strictly below the line and above the hyperbola nAnB=d. Finally, we provide an alternative proof of the conjecture about KD nonclassicality based on DFT.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37574783

RESUMO

BACKGROUND: Fatigue is a common symptom in cancer patients receiving radiotherapy. However, previous studies report inconsistent patterns of fatigue change. AIM: The aim of this study was to estimate changes in fatigue among patients with cancer before, during, and after radiotherapy. METHODS: Five databases (PubMed, SDOL, CINAHL Plus with Full Text, Medline [ProQuest], and ProQuest Dissertations) were searched for studies published from January 2006 to May 2021. Three effect sizes of fatigue change (immediate, short-term, and long-term) were calculated for each primary study using standardized mean difference. A random-effect model was used to combine effect sizes across studies. Subgroup analyses and meta-regression were performed to identify potential categorical and continuous moderators, respectively. RESULTS: Sixty-five studies were included in this meta-analysis. The weighted mean effect size for immediate, short-term, and long-term effects was 0.409 (p < .001; 95% CI [0.280, 0.537]), 0.303 (p < .001; 95% CI [0.189, 0.417]), and 0.201 (p = .05; 95% CI [-0.001, 0.404]), respectively. Studies with prostate cancer patients had a significantly higher short-term (0.588) and long-term weight mean effect size (0.531) than studies with breast (0.128, -0.072) or other cancers (0.287, 0.215). Higher radiotherapy dosage was significantly associated with a higher effect size for both immediate (ß = .0002, p < .05) and short-term (ß = .0002, p < .05) effect. LINKING EVIDENCE TO ACTION: Findings from this meta-analysis indicated that radiotherapy-induced fatigue (RIF) exist for more than 3 months after the completion of treatment. Assessment of radiation-induced fatigue in cancer patients should extend long after treatment completion, especially for patients with prostate cancer and patients receiving a higher radiation dose. Interventions to reduce fatigue tailored for different treatment phases may be developed.

9.
Antimicrob Agents Chemother ; 66(6): e0015122, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35647650

RESUMO

In Aspergillus fumigatus, the most prevalent resistance to azoles results from mutational modifications of the azole target protein Cyp51A, but there are non-cyp51A mutants resistant to azoles, and the mechanisms underlying the resistance of these strains remain to be explored. Here, we identified a novel cytochrome c oxidase, cox7c (W56*), nonsense mutation in the laboratory and found that it caused reduced colony growth and resistance to multiantifungal agents. Meanwhile, we revealed that cold storage is responsible for increased tolerance of conidia to itraconazole (ITC) stress, which further advances azole-resistant mutations (cryopreservation→ITC tolerance→azole resistance). The deletion or mutation of cox7c results explicitly in resistance to antifungal-targeting enzymes, including triazoles, polyenes, and allylamines, required for ergosterol synthesis, or resistance to fungal ergosterol. A high-performance liquid chromatography (HPLC) assay showed that the cox7c knockout strain decreased intracellular itraconazole concentration. In addition, the lack of Cox7c resulted in the accumulation of intracellular heme B. We validated that an endogenous increase in, or the exogenous addition of, heme B was capable of eliciting azole resistance, which was in good accordance with the phenotypic resistance analysis of cox7c mutants. Furthermore, RNA sequencing verified the elevated transcriptional expression levels of multidrug transport genes. Additionally, lower itraconazole-induced reactive oxygen species generation in mycelia of a cox7c-deletion strain suggested that this reduction may, in part, contribute to drug resistance. These findings increase our understanding of how A. fumigatus's direct responses to azoles promote fungal survival in the environment and address genetic mutations that arise from patients or environments.


Assuntos
Aspergillus fumigatus , Azóis , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Aspergillus fumigatus/metabolismo , Azóis/metabolismo , Azóis/farmacologia , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Ergosterol/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Heme/metabolismo , Humanos , Itraconazol/metabolismo , Itraconazol/farmacologia , Testes de Sensibilidade Microbiana , Proteínas Nucleares
10.
J Formos Med Assoc ; 120(1 Pt 1): 250-255, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32417175

RESUMO

BACKGROUND: To better understand population-specific tumor characteristics and behavior of conjunctival melanoma in Asian. METHODS: A retrospective cohort enrolled patients with primary conjunctival melanoma treated and followed up at Chang Gung Memorial Hospital (CGMH) in Taiwan between 1995 and 2015. Basic characteristics such as age, gender, tumor size, cell type, location, and TNM stage were recorded. Prognostic parameters included disease free interval, local recurrence, distant metastasis, and survival were analyzed. RESULTS: There were 20 patients enrolled in the study hospital between 1995 and 2015. All were histological proved by pathologists. Their mean age at diagnosis was 57.8 ± 15.9 years. The mean follow-up time was 68.7 ± 55.8 months. Mean tumor thickness was 6.5 ± 5.9 mm. Six patients developed local recurrence. Twelve patients had distant metastasis. Ten patients died from conjunctival melanoma. The 10 patients had greater mean tumor thickness (8.4 ± 7.5 mm) and shorter mean survival time (40.2 ± 24.1 months). Tumor thickness was found as a prognostic factor for survival time (HR = 1.15, P = 0.01). Age, gender, T stage, and tumor location were not significantly associated with survival. CONCLUSION: Different tumor characteristics were found in this cohort. Higher metastasis and mortality rate could suggest a more aggressive disease pattern. Tumor thickness was indicated as a prognostic factor for survival time and was greater in size in cases with distant metastasis. Early and more invasive intervention with closely follow-up may be indicated in these cases.


Assuntos
Melanoma , Recidiva Local de Neoplasia , Adulto , Idoso , Hospitais , Humanos , Melanoma/epidemiologia , Melanoma/terapia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Taiwan/epidemiologia
11.
Plant Physiol ; 180(2): 813-826, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30898971

RESUMO

Mitochondrial fission occurs frequently in plant cells, but its biological significance is poorly understood because mutants specifically impaired in mitochondrial fission do not show obvious defects in vegetative growth. Here, we revealed that the production of viable pollen was reduced in mutants lacking one of the three main proteins involved in mitochondrial fission in Arabidopsis (Arabidopsis thaliana), DYNAMIN-RELATED PROTEIN3A (DRP3A)/Arabidopsis DYNAMIN-LIKE PROTEIN2A, DRP3B, and ELONGATED MITOCHONDRIA1 (ELM1). In drp3b and elm1, young microspores contained an abnormal number of nuclei, and mature pollen had aberrant accumulation of lipids in their coat and an irregular pollen outer wall. Because the formation of the pollen wall and coat is mainly associated with tapetal function, we used 3D imaging to quantify geometric and textural features of cells and mitochondria in the tapetum at different stages, using isolated single tapetal cells in which the in vivo morphology and volume of cells and mitochondria were preserved. Tapetal cells and their mitochondria changed in the volume and morphology at different developmental stages. Defective mitochondrial fission in the elm1 and drp3b mutants caused changes in mitochondrial status, including mitochondrial elongation, abnormal mitochondrial ultrastructure, a decrease in cross-sectional area, and a slight alteration of mitochondrial distribution, as well as a large reduction in mitochondrial density. Our studies suggest that mitochondrial fission is required for proper mitochondrial status in the tapetum and possibly in pollen as well and therefore plays an important role for the production of viable pollen.


Assuntos
Imageamento Tridimensional , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Pólen/crescimento & desenvolvimento , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Forma Celular , Proteínas de Fluorescência Verde/metabolismo , Mitocôndrias/ultraestrutura , Mutação/genética , Pólen/citologia , Pólen/ultraestrutura
12.
Med Mycol ; 58(4): 543-551, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31290538

RESUMO

Aspergillus fumigatus is a pathogenic fungus responsible for invasive aspergillosis (IA). Typically, it can produce abundant conidia to survive and spread. The infection by A. fumigatus usually occurs in immunocompromised patients due to failed clearance of inhaled conidia. However, the incidence of aspergillosis in immunocompetent hosts has been increasing, the pathogenesis of which is still unknown. Our team previously obtained two clinical nonsporulating A. fumigatus isolates from non-immunocompromised patients, which only have the form of hyphae. This present study demonstrated the in vitro and in vivo characteristics of the two nonsporulating A. fumigatus isolates and verified that their conidiation defects are associated to abolished expression of the sporulation-related central regulatory pathway brlA gene. In addition, we confirmed the mutation site of brlA gene (c.657_660delTCCT) contributes to the nonsporulating phenotype in one clinical isolate. Plate assay showed that the two nonsporulating isolates have a similar resistance to antifungal drugs, cell wall disturbing substances, and oxidative stress compared with the wild-type reference Af293. Most important of all, we employed an immunocompetent mouse model to mimic the pathogenesis of pulmonary aspergillosis in non-immunocompromised patients. It revealed that the hyphae of two nonsporulating isolates and Af293 have similar virulence in immunocompetent hosts. Interestingly, the hyphae fragments of Af293 but not conidia are able to induce invasive aspergillosis in immunocompetent mice. In conclusion, our study indicate that the form of hyphae may play a dominant causative role in pulmonary aspergillosis of immunocompetent hosts rather than conidia.


Assuntos
Aspergillus fumigatus/classificação , Hifas/crescimento & desenvolvimento , Imunocompetência , Aspergilose Pulmonar/microbiologia , Aspergilose Pulmonar/patologia , Animais , Aspergillus fumigatus/isolamento & purificação , Aspergillus fumigatus/patogenicidade , Modelos Animais de Doenças , Farmacorresistência Fúngica/genética , Feminino , Proteínas Fúngicas/genética , Humanos , Hifas/patogenicidade , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Esporos Fúngicos/fisiologia , Fatores de Transcrição/genética , Virulência
13.
Int Ophthalmol ; 38(1): 293-299, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28176171

RESUMO

PURPOSE: To compare the efficacy of intravitreal ranibizumab between non-vitrectomized and vitrectomized eyes with diabetic macular edema (DME). STUDY DESIGN: A retrospective, nonrandomized, and comparative study. METHODS: From May 2013 to March 2016, 148 eyes of 148 patients with treatment-naïve center-involving DME were reviewed in one institution. Forty-six eyes underwent prior vitrectomy at least 3 months ago, and 102 eyes did not receive any vitrectomy. Three monthly then PRN intravitreal ranibizumab treatments were performed in all the patients with monthly follow-up for 6 months. Primary outcome measures included change in central foveal thickness (CFT) and best-corrected visual acuity (BCVA) at month 6. RESULTS: The CFT significantly reduced, and the BCVA significantly improved 6 months after ranibizumab injections in either vitrectomized or non-vitrectomized groups (p < 0.05). There was no difference between vitrectomized and non-vitrectomized eyes in baseline characteristics. Significantly better final BCVA and visual gain were found in non-vitrectomized eyes than in vitrectomized eyes (p = 0.01 and 0.03, respectively). Final CFT and CFT decrease were significantly greater in non-vitrectomized group than in vitrectomized group (p = 0.02 and 0.006, respectively). Injection number of ranibizumab was 4.12 ± 0.58 in non-vitrectomized eyes, significantly less than that in vitrectomized eyes (5.05 ± 0.71) during 6-month period (p < 0.001). There were no severe systemic/ocular adverse effects in both groups. CONCLUSIONS: Intravitreal ranibizumab was helpful for either vitrectomized or non-vitrectomized eyes with DME in short-term follow-up. Anatomical and functional improvements were greater in non-vitrectomized patients than in vitrectomized cases.


Assuntos
Diabetes Mellitus , Edema Macular/terapia , Ranibizumab/administração & dosagem , Vitrectomia , Inibidores da Angiogênese/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Injeções Intravítreas , Macula Lutea/patologia , Edema Macular/diagnóstico , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento , Acuidade Visual
14.
Artigo em Inglês | MEDLINE | ID: mdl-27799210

RESUMO

The rapid and global emergence of azole resistance in the human pathogen Aspergillus fumigatus has drawn attention. Thus, a thorough understanding of its mechanisms of drug resistance requires extensive exploration. In this study, we found that the loss of the putative calcium-dependent protein-encoding gene algA causes an increased frequency of azole-resistant A. fumigatus isolates. In contrast to previously identified azole-resistant isolates related to cyp51A mutations, only one isolate carries a point mutation in cyp51A (F219L mutation) among 105 independent stable azole-resistant isolates. Through next-generation sequencing (NGS), we successfully identified a new mutation (R243Q substitution) conferring azole resistance in the putative A. fumigatus farnesyltransferase Cox10 (AfCox10) (AFUB_065450). High-performance liquid chromatography (HPLC) analysis verified that the decreased absorption of itraconazole in related Afcox10 mutants is the primary reason for itraconazole resistance. Moreover, a complementation experiment by reengineering the mutation in a parental wild-type background strain demonstrated that both the F219L and R243Q mutations contribute to itraconazole resistance in an algA-independent manner. These data collectively suggest that the loss of algA results in an increased frequency of azole-resistant isolates with a non-cyp51A mutation. Our findings indicate that there are many unexplored non-cyp51A mutations conferring azole resistance in A. fumigatus and that algA defects make it possible to isolate drug-resistant alleles. In addition, our study suggests that genome-wide sequencing combined with alignment comparison analysis is an efficient approach to identify the contribution of single nucleotide polymorphism (SNP) diversity to drug resistance.


Assuntos
Aspergillus fumigatus/efeitos dos fármacos , Farmacorresistência Fúngica/genética , Farnesiltranstransferase/genética , Proteínas Fúngicas/genética , Mutação , Antifúngicos/farmacologia , Aspergillus fumigatus/genética , Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Farnesiltranstransferase/metabolismo , Proteínas Fúngicas/metabolismo , Expressão Gênica , Teste de Complementação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Itraconazol/farmacologia , Polimorfismo de Nucleotídeo Único
15.
Br J Neurosurg ; 31(4): 481-483, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27088540

RESUMO

Cerebral syphilitic gumma is extremely rare and easily misdiagnosed. We illustrate a case of a cerebral syphilitic gumma developed in just a few months mimicking a brain tumor in a HIV-negative patient and Treponema pallidum was detected in the cerebral syphilitic gumma.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neurossífilis/diagnóstico , Diagnóstico Diferencial , Erros de Diagnóstico , Soronegatividade para HIV , Humanos , Masculino , Pessoa de Meia-Idade , Sífilis/diagnóstico
16.
Worldviews Evid Based Nurs ; 14(3): 223-236, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28267893

RESUMO

BACKGROUND: Anxiety is a common form of psychological distress in patients with cancer. One recognized nonpharmacological intervention to reduce anxiety for various populations is hypnotherapy or hypnosis. However, its effect in reducing anxiety in cancer patients has not been systematically evaluated. AIM: This meta-analysis was designed to synthesize the immediate and sustained effects of hypnosis on anxiety of cancer patients and to identify moderators for these hypnosis effects. METHODS: Qualified studies including randomized controlled trials (RCT) and pre-post design studies were identified by searching seven electronic databases: Scopus, Medline Ovidsp, PubMed, PsycInfo-Ovid, Academic Search Premier, CINAHL Plus with FT-EBSCO, and SDOL. Effect size (Hedges' g) was computed for each study. Random-effect modeling was used to combine effect sizes across studies. All statistical analyses were conducted with Comprehensive Meta-Analysis, version 2 (Biostat, Inc., Englewood, NJ, USA). RESULTS: Our meta-analysis of 20 studies found that hypnosis had a significant immediate effect on anxiety in cancer patients (Hedges' g: 0.70-1.41, p < .01) and the effect was sustained (Hedges' g: 0.61-2.77, p < .01). The adjusted mean effect size (determined by Duvan and Tweedie's trim-and-fill method) was 0.46. RCTs had a significantly higher effect size than non-RCT studies. Higher mean effect sizes were also found with pediatric study samples, hematological malignancy, studies on procedure-related stressors, and with mixed-gender samples. Hypnosis delivered by a therapist was significantly more effective than self-hypnosis. LINKING EVIDENCE TO ACTION: Hypnosis can reduce anxiety of cancer patients, especially for pediatric cancer patients who experience procedure-related stress. We recommend therapist-delivered hypnosis should be preferred until more effective self-hypnosis strategies are developed.


Assuntos
Ansiedade/terapia , Hipnose , Neoplasias/psicologia , Resultado do Tratamento , Ansiedade/psicologia , Humanos , Neoplasias/terapia
17.
Proc Natl Acad Sci U S A ; 110(35): 14480-5, 2013 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23940319

RESUMO

During evolution, genomes expanded via whole-genome, segmental, tandem, and individual-gene duplications, and the emerged redundant paralogs would be eliminated or retained owing to selective neutrality or adaptive benefit and further functional divergence. Here we show that tandem paralogs can contribute adaptive quantitative benefit and thus have been retained in a lineage-specific manner. In Brassicaceae, a tandem oleosin gene cluster of five to nine paralogs encodes ample tapetum-specific oleosins located in abundant organelles called tapetosomes in flower anthers. Tapetosomes coordinate the storage of lipids and flavonoids and their transport to the adjacent maturing pollen as the coat to serve various functions. Transfer-DNA and siRNA mutants of Arabidopsis thaliana with knockout and knockdown of different tandem oleosin paralogs had quantitative and correlated loss of organized structures of the tapetosomes, pollen-coat materials, and pollen tolerance to dehydration. Complementation with the knockout paralog restored the losses. Cleomaceae is the family closest to Brassicaceae. Cleome species did not contain the tandem oleosin gene cluster, tapetum oleosin transcripts, tapetosomes, or pollen tolerant to dehydration. Cleome hassleriana transformed with an Arabidopsis oleosin gene for tapetum expression possessed primitive tapetosomes and pollen tolerant to dehydration. We propose that during early evolution of Brassicaceae, a duplicate oleosin gene mutated from expression in seed to the tapetum. The tapetum oleosin generated primitive tapetosomes that organized stored lipids and flavonoids for their effective transfer to the pollen surface for greater pollen vitality. The resulting adaptive benefit led to retention of tandem-duplicated oleosin genes for production of more oleosin and modern tapetosomes.


Assuntos
Brassicaceae/genética , Genes de Plantas , Proteínas de Plantas/genética , Pólen , Adaptação Fisiológica , Arabidopsis/genética , Brassicaceae/fisiologia , Dados de Sequência Molecular , Família Multigênica , Mutação , RNA Mensageiro/genética
18.
Fungal Genet Biol ; 81: 250-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25776795

RESUMO

Aspergillus fumigatus (A. fumigatus) commonly produces abundant and heavily melanized infectious conidia, which are the primary agents that cause invasive aspergillosis (IA) in immunocompromised patients. We isolated a white nonsporulating A. fumigatus strain (A1j) from an immunocompetent patient. It was identified by histopathological examination and morphological observation, and subsequently confirmed by DNA sequencing of internal transcribed spacer (ITS) regions and partial ß-tubulin genes. Neither a long waiting time nor passage on various medium types could stimulate the formation of spores and pigment. No significant relative difference was found in sensitivity to antifungal agents or cell wall destabilizing reagents, as compared to wild-type A. fumigatus Af293. Nevertheless, A1j was hypovirulent in the immunosuppressed mice model, consistent with the good result in our patient. RNA deep-sequencing analysis (RNA-seq) revealed that hundreds of transcripts were significantly dysregulated, including those related to pigmentation and sporulation. qRT-PCR confirmed the anergic state of key regulator brlA for sporulation under the induction of conidiation conditions, but without mutation. To the best of our knowledge, this is the first report of a white, nonsporulating A. fumigatus strain infection in an immunocompetent patient. In our opinion, A1j may represent a mutant of typical A. fumigatus, providing a new clue for identification of clinical A. fumigatus isolates. Furthermore, the good prognosis of our patient and the reduced virulence in the mice model infected with A1j highlight the potential of sporulation inhibitors as a new generation of antifungal agents.


Assuntos
Aspergilose/microbiologia , Aspergilose/patologia , Aspergillus fumigatus/crescimento & desenvolvimento , Mutação , Pigmentos Biológicos/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Animais , Aspergillus fumigatus/genética , Aspergillus fumigatus/isolamento & purificação , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Camundongos , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Tubulina (Proteína)/genética , Virulência
19.
Eukaryot Cell ; 13(2): 295-303, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24376003

RESUMO

Calcium-mediated signaling pathways are widely employed in eukaryotes and are implicated in the regulation of diverse biological processes. In Saccharomyces cerevisiae, at least two different calcium uptake systems have been identified: the high-affinity calcium influx system (HACS) and the low-affinity calcium influx system (LACS). Compared to the HACS, the LACS in fungi is not well known. In this study, FigA, a homolog of the LACS member Fig1 from S. cerevisiae, was functionally characterized in the filamentous fungus Aspergillus nidulans. Loss of figA resulted in retardant hyphal growth and a sharp reduction of conidial production. Most importantly, FigA is essential for the homothallic mating (self-fertilization) process; further, FigA is required for heterothallic mating (outcrossing) in the absence of HACS midA. Interestingly, in a figA deletion mutant, adding extracellular Ca(2+) rescued the hyphal growth defects but could not restore asexual and sexual reproduction. Furthermore, quantitative PCR results revealed that figA deletion sharply decreased the expression of brlA and nsdD, which are known as key regulators during asexual and sexual development, respectively. In addition, green fluorescent protein (GFP) tagging at the C terminus of FigA (FigA::GFP) showed that FigA localized to the center of the septum in mature hyphal cells, to the location between vesicles and metulae, and between the junctions of metulae and phialides in conidiophores. Thus, our findings suggest that FigA, apart from being a member of a calcium uptake system in A. nidulans, may play multiple unexplored roles during hyphal growth and asexual and sexual development.


Assuntos
Aspergillus nidulans/metabolismo , Cálcio/metabolismo , Proteínas Fúngicas/genética , Proteínas de Membrana/metabolismo , Reprodução Assexuada , Proteínas de Saccharomyces cerevisiae/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Aspergillus nidulans/genética , Aspergillus nidulans/fisiologia , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Deleção de Genes , Hifas/crescimento & desenvolvimento , Transporte de Íons , Proteínas de Membrana/química , Proteínas de Membrana/genética , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética
20.
Curr Alzheimer Res ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39318217

RESUMO

BACKGROUND: Amnestic Mild Cognitive Impairment (aMCI) is a prodromal phase of Alzheimer's disease. Although recent studies have focused on cortical thickness as a key indicator, cortical complexity has not been exhaustively investigated. OBJECTIVES: To investigate the altered patterns of cortical features in aMCI patients and their correlation with memory function for early identification. METHODS: 25 aMCI patients and 54 normal controls underwent neuropsychological assessments and 3D-T1 MRI scans. Cortical thickness and complexity measures were calculated using CAT12 software. Differences between groups were analyzed using two-sample t-tests, and multiple linear regression was employed to identify features associated with memory function. A support vector machine (SVM) model was constructed using multidimensional structural indicators to evaluate diagnostic performance. RESULTS: aMCI patients exhibited extensive reductions in cortical thickness (pFDR-corrected <0.05), with complexity reduction predominantly in the left parahippocampal, entorhinal, rostral anterior cingulate, fusiform, and orbitofrontal (pFWE-corrected<0.05). Cortical indicators exhibited robust correlations with auditory verbal learning test (AVLT) scores. Specifically, the fractal dimension of the left medial orbitofrontal region was independently and positively associated with AVLT-short delayed score (r=0.348, p=0.002), while the gyrification index of the left rostral anterior cingulate region showed independent positive correlations with AVLT-long delayed and recognition scores (r=0.408, p=0.000; r=0.332, p=0.003). Finally, the SVM model integrating these cortical features achieved an AUC of 0.91, with 82.28% accuracy, 76% sensitivity, and 85.19% specificity. CONCLUSION: Cortical morphological indicators provide important neuroimaging evidence for the early diagnosis of aMCI. Integrating multiple structural indicators significantly improves diagnostic accuracy.

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