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1.
Sensors (Basel) ; 23(17)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37687910

RESUMO

Wearable assistant devices play an important role in daily life for people with disabilities. Those who have hearing impairments may face dangers while walking or driving on the road. The major danger is their inability to hear warning sounds from cars or ambulances. Thus, the aim of this study is to develop a wearable assistant device with edge computing, allowing the hearing impaired to recognize the warning sounds from vehicles on the road. An EfficientNet-based, fuzzy rank-based ensemble model was proposed to classify seven audio sounds, and it was embedded in an Arduino Nano 33 BLE Sense development board. The audio files were obtained from the CREMA-D dataset and the Large-Scale Audio dataset of emergency vehicle sirens on the road, with a total number of 8756 files. The seven audio sounds included four vocalizations and three sirens. The audio signal was converted into a spectrogram by using the short-time Fourier transform for feature extraction. When one of the three sirens was detected, the wearable assistant device presented alarms by vibrating and displaying messages on the OLED panel. The performances of the EfficientNet-based, fuzzy rank-based ensemble model in offline computing achieved an accuracy of 97.1%, precision of 97.79%, sensitivity of 96.8%, and specificity of 97.04%. In edge computing, the results comprised an accuracy of 95.2%, precision of 93.2%, sensitivity of 95.3%, and specificity of 95.1%. Thus, the proposed wearable assistant device has the potential benefit of helping the hearing impaired to avoid traffic accidents.


Assuntos
Perda Auditiva , Dispositivos Eletrônicos Vestíveis , Humanos , Ambulâncias , Audição , Acidentes de Trânsito
2.
Environ Microbiol ; 24(3): 1308-1325, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34708512

RESUMO

Terpios hoshinota is an aggressive, space-competing sponge that kills various stony corals. Outbreaks of this species have led to intense damage to coral reefs in many locations. Here, the first large-scale 16S rRNA gene survey across three oceans revealed that bacteria related to the taxa Prochloron, Endozoicomonas, SAR116, Ruegeria, and unclassified Proteobacteria were prevalent in T. hoshinota. A Prochloron-related bacterium was the most dominant and prevalent cyanobacterium in T. hoshinota. The complete genome of this uncultivated cyanobacterium and pigment analysis demonstrated that it has phycobiliproteins and lacks chlorophyll b, which is inconsistent with the definition of Prochloron. Furthermore, the cyanobacterium was phylogenetically distinct from Prochloron, strongly suggesting that it should be a sister taxon to Prochloron. Therefore, we proposed this symbiotic cyanobacterium as a novel species under the new genus Candidatus Paraprochloron terpiosi. Comparative genomic analyses revealed that 'Paraprochloron' and Prochloron exhibit distinct genomic features and DNA replication machinery. We also characterized the metabolic potentials of 'Paraprochloron terpiosi' in carbon and nitrogen cycling and propose a model for interactions between it and T. hoshinota. This study builds a foundation for the study of the T. hoshinota microbiome and paves the way for better understanding of ecosystems involving this coral-killing sponge.


Assuntos
Antozoários , Cianobactérias , Microbiota , Poríferos , Animais , Antozoários/microbiologia , Recifes de Corais , Cianobactérias/metabolismo , Poríferos/genética , Prevalência , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Simbiose
3.
Soft Matter ; 17(2): 397-409, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33174582

RESUMO

The columnar mesophase, in which the molecular or supramolecular building blocks with rod-like geometry pack into two-dimensional (2D) lattices, is an important class of mesomorphic structure having been found in various liquid crystalline materials for practical applications. The cylindrical micelles assembled by amphiphilic surfactants may also form columnar mesophases with the micelle packing symmetry being tunable by the molecular characteristics of the surfactants. In this study, we demonstrate that a positively charged tree-like polymer, poly(amidoamine) (PAMAM) G4 dendrimer, acted as an effective structure-directing agent for the columnar mesophase of a common anionic surfactant, sodium dodecyl sulfate (SDS), via their electrostatic interaction. By adjusting the dendrimer charge density and the nominal binding ratio (Xn) of SDS to dendrimer, the electrostatic complexes self-assembled to form a body-centered cubic (BCC) sphere phase, wherein the dendrimers were staggered between the interspaces of the SDS spherical micelles packed in the BCC lattice. Four types of 2D columnar mesophase composed of SDS cylindrical micelles and dendrimers were accommodated within the interstitial tunnels, including the hexagonal columnar phase (Colhex), simple rectangular columnar phase (Colsr), oblique columnar phase (Colob) and centered rectangular columnar phase (Colcr). A detailed analysis of the geometry of the dendrimer in the columnar mesophases revealed that the structural transition was governed by the interplay among the lateral and axial deformations of the dendrimer, and the deformation of the SDS micelle cross section for achieving effective charge matching and accommodation of the dendrimer. The present study demonstrated the power of the dendrimer in directing the long-range ordered packing of oppositely charged cylinders to yield a rich structural polymorphism of the columnar mesophase that may be exploited for the development of functional materials.

4.
Nature ; 510(7505): 427-31, 2014 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-24814342

RESUMO

Sulphur is an essential element for life and is ubiquitous in living systems. Yet how the sulphur atom is incorporated into many sulphur-containing secondary metabolites is poorly understood. For bond formation between carbon and sulphur in primary metabolites, the major ionic sulphur sources are the persulphide and thiocarboxylate groups on sulphur-carrier (donor) proteins. Each group is post-translationally generated through the action of a specific activating enzyme. In all reported bacterial cases, the gene encoding the enzyme that catalyses the carbon-sulphur bond formation reaction and that encoding the cognate sulphur-carrier protein exist in the same gene cluster. To study the production of the 2-thiosugar moiety in BE-7585A, an antibiotic from Amycolatopsis orientalis, we identified a putative 2-thioglucose synthase, BexX, whose protein sequence and mode of action seem similar to those of ThiG, the enzyme that catalyses thiazole formation in thiamine biosynthesis. However, no gene encoding a sulphur-carrier protein could be located in the BE-7585A cluster. Subsequent genome sequencing uncovered a few genes encoding sulphur-carrier proteins that are probably involved in the biosynthesis of primary metabolites but only one activating enzyme gene in the A. orientalis genome. Further experiments showed that this activating enzyme can adenylate each of these sulphur-carrier proteins and probably also catalyses the subsequent thiolation, through its rhodanese domain. A proper combination of these sulphur-delivery systems is effective for BexX-catalysed 2-thioglucose production. The ability of BexX to selectively distinguish sulphur-carrier proteins is given a structural basis using X-ray crystallography. This study is, to our knowledge, the first complete characterization of thiosugar formation in nature and also demonstrates the receptor promiscuity of the A. orientalis sulphur-delivery system. Our results also show that co-opting the sulphur-delivery machinery of primary metabolism for the biosynthesis of sulphur-containing natural products is probably a general strategy found in nature.


Assuntos
Actinomycetales/enzimologia , Actinomycetales/genética , Proteínas de Transporte/metabolismo , Ligases/química , Enxofre/metabolismo , Tioaçúcares/metabolismo , Actinomycetales/metabolismo , Proteínas de Transporte/química , Domínio Catalítico , Genoma Bacteriano/genética , Ligases/genética , Ligases/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína
5.
Breast Cancer Res ; 21(1): 87, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31383035

RESUMO

BACKGROUND: Approximately two thirds of patients with localized triple-negative breast cancer (TNBC) harbor residual disease (RD) after neoadjuvant chemotherapy (NAC) and have a high risk-of-recurrence. Targeted therapeutic development for TNBC is of primary significance as no targeted therapies are clinically indicated for this aggressive subset. In view of this, we conducted a comprehensive molecular analysis and correlated molecular features of chemorefractory RD tumors with recurrence for the purpose of guiding downstream therapeutic development. METHODS: We assembled DNA and RNA sequencing data from RD tumors as well as pre-operative biopsies, lymphocytic infiltrate, and survival data as part of a molecular correlative to a phase II post-neoadjuvant clinical trial. Matched somatic mutation, gene expression, and lymphocytic infiltrate were assessed before and after chemotherapy to understand how tumors evolve during chemotherapy. Kaplan-Meier survival analyses were conducted categorizing cancers with TP53 mutations by the degree of loss as well as by the copy number of a locus of 18q corresponding to the SMAD2, SMAD4, and SMAD7 genes. RESULTS: Analysis of matched somatic genomes pre-/post-NAC revealed chaotic acquisition of copy gains and losses including amplification of prominent oncogenes. In contrast, significant gains in deleterious point mutations and insertion/deletions were not observed. No trends between clonal evolution and recurrence were identified. Gene expression data from paired biopsies revealed enrichment of actionable regulators of stem cell-like behavior and depletion of immune signaling, which was corroborated by total lymphocytic infiltrate, but was not associated with recurrence. Novel characterization of TP53 mutation revealed prognostically relevant subgroups, which were linked to MYC-driven transcriptional amplification. Finally, somatic gains in 18q were associated with poor prognosis, likely driven by putative upregulation of TGFß signaling through the signal transducer SMAD2. CONCLUSIONS: We conclude TNBCs are dynamic during chemotherapy, demonstrating complex plasticity in subclonal diversity, stem-like qualities, and immune depletion, but somatic alterations of TP53/MYC and TGFß signaling in RD samples are prominent drivers of recurrence, representing high-yield targets for additional interrogation.


Assuntos
Biomarcadores Tumorais , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Variações do Número de Cópias de DNA , Feminino , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Estimativa de Kaplan-Meier , Mutação , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Neoplasia Residual , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Transdução de Sinais , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/mortalidade , Proteína Supressora de Tumor p53/genética
6.
Phys Rev Lett ; 123(23): 238002, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868485

RESUMO

Manipulating building-block nanomaterials to form an ordered superstructure in a dilute and spacer-free solution phase challenges the existing 5-nm node lithography and nanorobotics. The cooperative nature of nanocrystals, polymers, and cells can lead to superarrays or colloidal crystals. For known highly ordered systems, the characteristic length of materials, defined as the shortest dimension of objects, is generally larger than their separations. A spacer (small-molecule surfactant or polymer) is typically required to diminish short range van der Waals attraction, which results in a glassy or liquid state. Herein we propose a new concept of achieving highly ordered nano-objects in a dilute and spacer-free system via the synergistic effects of excellent solvation and appropriate constraints on rotational motion. As a proof of concept, this study demonstrates that aluminosilicate nanotubes (AlSiNTs) suspended in water under dilute conditions (e.g., 1.0 wt%) can spontaneously form hexagonal arrays with an intertubular distance as large as tens of nanometers. The separation distance of the ordered superstructure is also tunable via controlling the concentration and length of nanotubes. These superaligned structures are probed using small-angle x-ray scattering and cryo-TEM characterizations, with underlying mechanisms investigated at an atomic level using molecular dynamics simulations. The concept and discovery of this work can open up opportunities to a variety of applications including visible-UV photonics and nanolithography, and may be generalizable to other nano-object systems that fulfill similar requirements.

7.
Development ; 141(12): 2402-13, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24850856

RESUMO

The ability of adult stem cells to reside in a quiescent state is crucial for preventing premature exhaustion of the stem cell pool. However, the intrinsic epigenetic factors that regulate spermatogonial stem cell quiescence are largely unknown. Here, we investigate in mice how DNA methyltransferase 3-like (DNMT3L), an epigenetic regulator important for interpreting chromatin context and facilitating de novo DNA methylation, sustains the long-term male germ cell pool. We demonstrated that stem cell-enriched THY1(+) spermatogonial stem/progenitor cells (SPCs) constituted a DNMT3L-expressing population in postnatal testes. DNMT3L influenced the stability of promyelocytic leukemia zinc finger (PLZF), potentially by downregulating Cdk2/CDK2 expression, which sequestered CDK2-mediated PLZF degradation. Reduced PLZF in Dnmt3l KO THY1(+) cells released its antagonist, Sal-like protein 4A (SALL4A), which is associated with overactivated ERK and AKT signaling cascades. Furthermore, DNMT3L was required to suppress the cell proliferation-promoting factor SALL4B in THY1(+) SPCs and to prevent premature stem cell exhaustion. Our results indicate that DNMT3L is required to delicately balance the cycling and quiescence of SPCs. These findings reveal a novel role for DNMT3L in modulating postnatal SPC cell fate decisions.


Assuntos
Células-Tronco Adultas/metabolismo , DNA (Citosina-5-)-Metiltransferases/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Espermatogônias/metabolismo , Alelos , Animais , Proliferação de Células , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Epigênese Genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Heterozigoto , Masculino , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt/metabolismo , Testículo/metabolismo , Fatores de Transcrição/metabolismo , Dedos de Zinco
9.
J Formos Med Assoc ; 114(6): 553-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26062968

RESUMO

Treatment and disposition of homeless patients with schizophrenia represent a great challenge in clinical practice. We report a case of this special population, and discuss the development of homelessness, the difficulty in disposition, their utilization of health services, and possible applications of mandatory community treatment in this group of patients. A 51-year-old homeless female was brought to an emergency department for left femur fracture caused by an assault. She was diagnosed with schizophrenia about 20 years ago but received little help from mental health services over the decades. During hospitalization, her psychotic symptoms were only partially responsive to treatment. Her family refused to handle caretaking duties. The social welfare system was mobilized for long-term disposition. Homeless patients with schizophrenia are characterized by family disruption, poor adherence to health care, and multiple emergency visits and hospitalization. We hope this article can provide information about the current mental health policy to medical personnel. It is possible that earlier intervention and better outcome can be achieved by utilizing mandatory community treatment in the future, as well as preventing patients with schizophrenia from losing shelters.


Assuntos
Psiquiatria Comunitária/normas , Pessoas Mal Alojadas/psicologia , Serviços de Saúde Mental/estatística & dados numéricos , Esquizofrenia/terapia , Seguridade Social/legislação & jurisprudência , Serviço Hospitalar de Emergência , Feminino , Fraturas do Colo Femoral/diagnóstico , Hospitalização , Habitação , Humanos , Programas Obrigatórios/legislação & jurisprudência , Pessoa de Meia-Idade , Taiwan
10.
J Adv Res ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38548265

RESUMO

INTRODUCTION: The clinical presentations of dry eye disease (DED) and depression (DEP) often comanifest. However, the robustness and the mechanisms underlying this association were undetermined. OBJECTIVES: To this end, we set up a three-segment study that employed multimodality results (meta-analysis, genome-wide association study [GWAS] and Mendelian randomization [MR]) to elucidate the association, common pathways and causality between DED and DEP. METHODS: A meta-analysis comprising 26 case-control studies was first conducted to confirm the DED-DEP association. Next, we performed a linkage disequilibrium (LD)-adjusted GWAS and targeted phenotype association study (PheWAS) in East Asian TW Biobank (TWB) and European UK Biobank (UKB) populations. Single-nucleotide polymorphisms (SNPs) were further screened for molecular interactions and common pathways at the functional gene level. To further elucidate the activated pathways in DED and DEP, a systemic transcriptome review was conducted on RNA sequencing samples from the Gene Expression Omnibus. Finally, 48 MR experiments were implemented to examine the bidirectional causation between DED and DEP. RESULTS: Our meta-analysis showed that DED patients are associated with an increased DEP prevalence (OR = 1.83), while DEP patients have a concurrent higher risk of DED (OR = 2.34). Notably, cross-disease GWAS analysis revealed that similar genetic architecture (rG = 0.19) and pleiotropic functional genes contributed to phenotypes in both diseases. Through protein-protein interaction and ontology convergence, we summarized the pleiotropic functional genes under the ontology of immune activation, which was further validated by a transcriptome systemic review. Importantly, the inverse variance-weighted (IVW)-MR experiments in both TWB and UKB populations (p value <0.001) supported the bidirectional exposure-outcome causation for DED-to-DEP and DEP-to-DED. Despite stringent LD-corrected instrumental variable re-selection, the bidirectional causation between DED and DEP remained. CONCLUSION: With the multi-modal evidence combined, we consolidated the association and causation between DED and DEP.

11.
Microbiol Resour Announc ; 12(1): e0087722, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36541816

RESUMO

Endozoicomonas euniceicola EF212T and Endozoicomonas gorgoniicola PS125T were isolated from soft corals (Eunicea fusca and Plexaura sp., respectively) and sequenced using a PacBio Sequel IIe sequencer. This is the first report of the genome sequences of culturable octocoral-isolated Endozoicomonas strains.

12.
J Acute Med ; 12(3): 122-125, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36313605

RESUMO

Japanese encephalitis (JE) is critical epidemic encephalitis caused by the JE virus (JEV) in Southeast Asia. The World Health Organization defined "acute encephalitis syndrome" (AES) as an acute onset of fever with a change of mental status and/or new-onset seizure, mainly for the surveillance of JE. The key clues for the diagnosis include the patient age group of unvaccinated era or waning vaccine-induced immunity and the history of possible mosquito bites in epidemic areas. We report a 47-year old man who is in an unvaccinated era with potential waning immunity. The patient presented with fever and altered mental status for 2 days. He was speechless and could not follow commands. The patient had gone camping in the countryside a week before the visit. At the emergency department, neck stiffness was noted. There was a leukocytosis with a left shift by blood cell count. The brain computed tomography was essentially normal. The cerebrospinal fluid (CSF) sample via lumbar puncture showed leukocytosis, a high protein level, and a low sugar level in comparison to serum tests. Further antibody test of CSF confirmed the diagnosis. Magnetic resonance imaging (MRI) of the brain revealed a high signal in the right thalamus and a mildly swollen left caudate nucleus 4 days after admission. He was extubated and finally discharged with partial dependency on activities of daily living. This case reminds us of the JE in AES. Emergency physicians should be aware of the suspicious case of unvaccinated age or waning immunity and possible mosquito bites in epidemic areas. The role of MRI on JE was also discussed in this article.

13.
Sci Adv ; 8(27): eabo2431, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35857470

RESUMO

Bacteria commonly form aggregates in a range of coral species [termed coral-associated microbial aggregates (CAMAs)], although these structures remain poorly characterized despite extensive efforts studying the coral microbiome. Here, we comprehensively characterize CAMAs associated with Stylophora pistillata and quantify their cell abundance. Our analysis reveals that multiple Endozoicomonas phylotypes coexist inside a single CAMA. Nanoscale secondary ion mass spectrometry imaging revealed that the Endozoicomonas cells were enriched with phosphorus, with the elemental compositions of CAMAs different from coral tissues and endosymbiotic Symbiodiniaceae, highlighting a role in sequestering and cycling phosphate between coral holobiont partners. Consensus metagenome-assembled genomes of the two dominant Endozoicomonas phylotypes confirmed their metabolic potential for polyphosphate accumulation along with genomic signatures including type VI secretion systems allowing host association. Our findings provide unprecedented insights into Endozoicomonas-dominated CAMAs and the first direct physiological and genomic linked evidence of their biological role in the coral holobiont.

14.
J Clin Oncol ; 40(4): 345-355, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34910554

RESUMO

PURPOSE: Patients with triple-negative breast cancer (TNBC) with residual disease after neoadjuvant chemotherapy (NAC) have high risk of recurrence with prior data suggesting improved outcomes with capecitabine. Targeted agents have demonstrated activity across multiple cancer types. BRE12-158 was a phase II, multicenter trial that randomly allocated patients with TNBC with residual disease after NAC to genomically directed therapy versus treatment of physician choice (TPC). PATIENTS AND METHODS: From March 2014 to December 2018, 193 patients were enrolled. Residual tumors were sequenced using a next-generation sequencing test. A molecular tumor board adjudicated all results. Patients were randomly allocated to four cycles of genomically directed therapy (arm A) versus TPC (arm B). Patients without a target were assigned to arm B. Primary end point was 2-year disease-free survival (DFS) among randomly assigned patients. Secondary/exploratory end points included distant disease-free survival, overall survival, toxicity assessment, time-based evolution of therapy, and drug-specific outcomes. RESULTS: One hundred ninety-three patients were randomly allocated or were assigned to arm B. The estimated 2-year DFS for the randomized population only was 56.6% (95% CI, 0.45 to 0.70) for arm A versus 62.4% (95% CI, 0.52 to 0.75) for arm B. No difference was seen in DFS, distant disease-free survival, or overall survival for the entire or randomized populations. There was increased uptake of capecitabine for TPC over time. Patients randomly allocated later had less distant recurrences. Circulating tumor DNA status remained a significant predictor of outcome with some patients demonstrating clearance with postneoadjuvant therapy. CONCLUSION: Genomically directed therapy was not superior to TPC for patients with residual TNBC after NAC. Capecitabine should remain the standard of care; however, the activity of other agents in this setting provides rationale for testing optimal combinations to improve outcomes. Circulating tumor DNA should be considered a standard covariate for trials in this setting.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Capecitabina/uso terapêutico , DNA Tumoral Circulante/genética , Terapia Neoadjuvante , Medicina de Precisão , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Capecitabina/efeitos adversos , Tomada de Decisão Clínica , Intervalo Livre de Doença , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Neoplasia Residual , Seleção de Pacientes , Valor Preditivo dos Testes , Fatores de Tempo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia
15.
J Neurochem ; 118(2): 288-303, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21554323

RESUMO

Spinocerebellar ataxia type 17 (SCA17) is an autosomal dominant inherited disorder characterized by degeneration of spinocerebellar tracts and selected brainstem neurons owing to the expansion of a CAG repeat of the human TATA-binding protein (hTBP) gene. To gain insight into the pathogenesis of this hTBP mutation, we generated transgenic mice with the mutant hTBP gene driven by the Purkinje specific protein (Pcp2/L7) gene promoter. Mice with the expanded hTBP allele developed ataxia within 2-5 months. Behavioral analysis of L7-hTBP transgenic mice showed reduced fall latency in a rotarod assay. Purkinje cell degeneration was identified by immunostaining of calbindin and IP3R1. Reactive gliosis and neuroinflammation occurred in the transgenic cerebellum, accompanied by up-regulation of GFAP and Iba1. The L7-hTBP transgenic mice were thus confirmed to recapitulate the SCA17 phenotype and were used as a disease model to explore the potential of granulocyte-colony stimulating factor in SCA17 treatment. Our results suggest that granulocyte-colony stimulating factor has a neuroprotective effect in these transgenic mice, ameliorating their neurological and behavioral deficits. These data indicate that the expression of the mutant hTBP in Purkinje cells is sufficient to produce cell degeneration and an ataxia phenotype, and constitutes a good model for better analysis of the neurodegeneration in SCA17.


Assuntos
Modelos Animais de Doenças , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Ataxias Espinocerebelares/genética , Proteína de Ligação a TATA-Box/genética , Animais , Feminino , Humanos , Camundongos , Camundongos Transgênicos , Fenótipo , Ataxias Espinocerebelares/metabolismo , Ataxias Espinocerebelares/prevenção & controle , Proteína de Ligação a TATA-Box/uso terapêutico
16.
Commun Biol ; 4(1): 996, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34426638

RESUMO

Most of Earth's bacteria have yet to be cultivated. The metabolic and functional potentials of these uncultivated microorganisms thus remain mysterious, and the metagenome-assembled genome (MAG) approach is the most robust method for uncovering these potentials. However, MAGs discovered by conventional metagenomic assembly and binning are usually highly fragmented genomes with heterogeneous sequence contamination. In this study, we combined Illumina and Nanopore data to develop a new workflow to reconstruct 233 MAGs-six novel bacterial orders, 20 families, 66 genera, and 154 species-from Lake Shunet, a secluded meromictic lake in Siberia. With our workflow, the average N50 of reconstructed MAGs greatly increased 10-40-fold compared to when the conventional Illumina assembly and binning method were used. More importantly, six complete MAGs were recovered from our datasets. The recovery of 154 novel species MAGs from a rarely explored lake greatly expands the current bacterial genome encyclopedia.


Assuntos
Bactérias/isolamento & purificação , Genoma Bacteriano , Sequenciamento de Nucleotídeos em Larga Escala , Lagos/microbiologia , Metagenoma , Sequenciamento por Nanoporos , Bactérias/genética , Sibéria
17.
Microb Genom ; 7(5)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33952388

RESUMO

Endolithic microbial symbionts in the coral skeleton may play a pivotal role in maintaining coral health. However, compared to aerobic micro-organisms, research on the roles of endolithic anaerobic micro-organisms and microbe-microbe interactions in the coral skeleton are still in their infancy. In our previous study, we showed that a group of coral-associated Prosthecochloris (CAP), a genus of anaerobic green sulphur bacteria, was dominant in the skeleton of the coral Isopora palifera. Though CAP is diverse, the 16S rRNA phylogeny presents it as a distinct clade separate from other free-living Prosthecochloris. In this study, we build on previous research and further characterize the genomic and metabolic traits of CAP by recovering two new high-quality CAP genomes - Candidatus Prosthecochloris isoporae and Candidatus Prosthecochloris sp. N1 - from the coral I. palifera endolithic cultures. Genomic analysis revealed that these two CAP genomes have high genomic similarities compared with other Prosthecochloris and harbour several CAP-unique genes. Interestingly, different CAP species harbour various pigment synthesis and sulphur metabolism genes, indicating that individual CAPs can adapt to a diversity of coral microenvironments. A novel high-quality genome of sulfate-reducing bacterium (SRB)- Candidatus Halodesulfovibrio lyudaonia - was also recovered from the same culture. The fact that CAP and various SRB co-exist in coral endolithic cultures and coral skeleton highlights the importance of SRB in the coral endolithic community. Based on functional genomic analysis of Ca. P. sp. N1, Ca. P. isoporae and Ca. H. lyudaonia, we also propose a syntrophic relationship between the SRB and CAP in the coral skeleton.


Assuntos
Antozoários/microbiologia , Chlorobi/classificação , Chlorobi/genética , Chlorobi/metabolismo , Genômica , Filogenia , Sulfatos/metabolismo , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , DNA Bacteriano/genética , Desulfovibrionaceae , Genoma , Metagenoma , RNA Ribossômico 16S/genética
18.
Mol Ther Nucleic Acids ; 20: 480-490, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32278307

RESUMO

Current antiviral therapy fails to cure chronic hepatitis B virus (HBV) infection because of persistent covalently closed circular DNA (cccDNA). CRISPR/Cas9-mediated specific cleavage of cccDNA is a potentially curative strategy for chronic hepatitis B (CHB). However, the CRISPR/Cas system inevitably targets integrated HBV DNA and induces double-strand breaks (DSBs) of host genome, bearing the risk of genomic rearrangement and damage. Herein, we examined the utility of recently developed CRISPR/Cas-mediated "base editors" (BEs) in inactivating HBV gene expression without cleavage of DNA. Candidate target sites of the SpCas9-derived BE and its variants in HBV genomes were screened for generating nonsense mutations of viral genes with individual guide RNAs (gRNAs). SpCas9-BE with certain gRNAs effectively base-edited polymerase and surface genes and reduced HBV gene expression in cells harboring integrated HBV genomes, but induced very few insertions or deletions (indels). Interestingly, some point mutations introduced by base editing resulted in simultaneous suppression of both polymerase and surface genes. Finally, the episomal cccDNA was successfully edited by SpCas9-BE for suppression of viral gene expression in an in vitro HBV infection system. In conclusion, Cas9-mediated base editing is a potential strategy to cure CHB by permanent inactivation of integrated HBV DNA and cccDNA without DSBs of the host genome.

19.
JAMA Oncol ; 6(9): 1410-1415, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32644110

RESUMO

Importance: A significant proportion of patients with early-stage triple-negative breast cancer (TNBC) are treated with neoadjuvant chemotherapy. Sequencing of circulating tumor DNA (ctDNA) after surgery, along with enumeration of circulating tumor cells (CTCs), may be used to detect minimal residual disease and assess which patients may experience disease recurrence. Objective: To determine whether the presence of ctDNA and CTCs after neoadjuvant chemotherapy in patients with early-stage TNBC is independently associated with recurrence and clinical outcomes. Design, Setting, and Participants: A preplanned secondary analysis was conducted from March 26, 2014, to December 18, 2018, using data from 196 female patients in BRE12-158, a phase 2 multicenter randomized clinical trial that randomized patients with early-stage TNBC who had residual disease after neoadjuvant chemotherapy to receive postneoadjuvant genomically directed therapy vs treatment of physician choice. Patients had blood samples collected for ctDNA and CTCs at time of treatment assignment; ctDNA analysis with survival was performed for 142 patients, and CTC analysis with survival was performed for 123 patients. Median clinical follow-up was 17.2 months (range, 0.3-58.3 months). Interventions: Circulating tumor DNA was sequenced using the FoundationACT or FoundationOneLiquid Assay, and CTCs were enumerated using an epithelial cell adhesion molecule-based, positive-selection microfluidic device. Main Outcomes and Measures: Primary outcomes were distant disease-free survival (DDFS), disease-free survival (DFS), and overall survival (OS). Results: Among 196 female patients (mean [SD] age, 49.6 [11.1] years), detection of ctDNA was significantly associated with inferior DDFS (median DDFS, 32.5 months vs not reached; hazard ratio [HR], 2.99; 95% CI, 1.38-6.48; P = .006). At 24 months, DDFS probability was 56% for ctDNA-positive patients compared with 81% for ctDNA-negative patients. Detection of ctDNA was similarly associated with inferior DFS (HR, 2.67; 95% CI, 1.28-5.57; P = .009) and inferior OS (HR, 4.16; 95% CI,1.66-10.42; P = .002). The combination of ctDNA and CTCs provided additional information for increased sensitivity and discriminatory capacity. Patients who were ctDNA positive and CTC positive had significantly inferior DDFS compared with those who were ctDNA negative and CTC negative (median DDFS, 32.5 months vs not reached; HR, 5.29; 95% CI, 1.50-18.62; P = .009). At 24 months, DDFS probability was 52% for patients who were ctDNA positive and CTC positive compared with 89% for those who were ctDNA negative and CTC negative. Similar trends were observed for DFS (HR, 3.15; 95% CI, 1.07-9.27; P = .04) and OS (HR, 8.60; 95% CI, 1.78-41.47; P = .007). Conclusions and Relevance: In this preplanned secondary analysis of a randomized clinical trial, detection of ctDNA and CTCs in patients with early-stage TNBC after neoadjuvant chemotherapy was independently associated with disease recurrence, which represents an important stratification factor for future postneoadjuvant trials. Trial Registration: ClinicalTrials.gov Identifier: NCT02101385.


Assuntos
DNA Tumoral Circulante/genética , Recidiva Local de Neoplasia/tratamento farmacológico , Células Neoplásicas Circulantes/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adolescente , Adulto , DNA Tumoral Circulante/efeitos dos fármacos , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Adulto Jovem
20.
NPJ Breast Cancer ; 3: 24, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28685160

RESUMO

Next-generation sequencing to detect circulating tumor DNA is a minimally invasive method for tumor genotyping and monitoring therapeutic response. The majority of studies have focused on detecting circulating tumor DNA from patients with metastatic disease. Herein, we tested whether circulating tumor DNA could be used as a biomarker to predict relapse in triple-negative breast cancer patients with residual disease after neoadjuvant chemotherapy. In this study, we analyzed samples from 38 early-stage triple-negative breast cancer patients with matched tumor, blood, and plasma. Extracted DNA underwent library preparation and amplification using the Oncomine Research Panel consisting of 134 cancer genes, followed by high-coverage sequencing and bioinformatics. We detected high-quality somatic mutations from primary tumors in 33 of 38 patients. TP53 mutations were the most prevalent (82%) followed by PIK3CA (16%). Of the 33 patients who had a mutation identified in their primary tumor, we were able to detect circulating tumor DNA mutations in the plasma of four patients (three TP53 mutations, one AKT1 mutation, one CDKN2A mutation). All four patients had recurrence of their disease (100% specificity), but sensitivity was limited to detecting only 4 of 13 patients who clinically relapsed (31% sensitivity). Notably, all four patients had a rapid recurrence (0.3, 4.0, 5.3, and 8.9 months). Patients with detectable circulating tumor DNA had an inferior disease free survival (p < 0.0001; median disease-free survival: 4.6 mos. vs. not reached; hazard ratio = 12.6, 95% confidence interval: 3.06-52.2). Our study shows that next-generation circulating tumor DNA sequencing of triple-negative breast cancer patients with residual disease after neoadjuvant chemotherapy can predict recurrence with high specificity, but moderate sensitivity. For those patients where circulating tumor DNA is detected, recurrence is rapid.

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