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1.
Nature ; 578(7796): 572-576, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051590

RESUMO

Levels of gene expression underpin organismal phenotypes1,2, but the nature of selection that acts on gene expression and its role in adaptive evolution remain unknown1,2. Here we assayed gene expression in rice (Oryza sativa)3, and used phenotypic selection analysis to estimate the type and strength of selection on the levels of more than 15,000 transcripts4,5. Variation in most transcripts appears (nearly) neutral or under very weak stabilizing selection in wet paddy conditions (with median standardized selection differentials near zero), but selection is stronger under drought conditions. Overall, more transcripts are conditionally neutral (2.83%) than are antagonistically pleiotropic6 (0.04%), and transcripts that display lower levels of expression and stochastic noise7-9 and higher levels of plasticity9 are under stronger selection. Selection strength was further weakly negatively associated with levels of cis-regulation and network connectivity9. Our multivariate analysis suggests that selection acts on the expression of photosynthesis genes4,5, but that the efficacy of selection is genetically constrained under drought conditions10. Drought selected for earlier flowering11,12 and a higher expression of OsMADS18 (Os07g0605200), which encodes a MADS-box transcription factor and is a known regulator of early flowering13-marking this gene as a drought-escape gene11,12. The ability to estimate selection strengths provides insights into how selection can shape molecular traits at the core of gene action.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , Seleção Genética/genética , Secas , Evolução Molecular , Flores/genética , Flores/crescimento & desenvolvimento , Aptidão Genética/genética , Oryza/crescimento & desenvolvimento , Fotossíntese/genética , Folhas de Planta/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Fatores de Tempo , Fatores de Transcrição/metabolismo
2.
Plant Cell ; 33(4): 1118-1134, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-33580702

RESUMO

Telomeres are highly repetitive DNA sequences found at the ends of chromosomes that protect the chromosomes from deterioration duringcell division. Here, using whole-genome re-sequencing and terminal restriction fragment assays, we found substantial natural intraspecific variation in telomere length in Arabidopsis thaliana, rice (Oryza sativa), and maize (Zea mays). Genome-wide association study (GWAS) mapping in A. thaliana identified 13 regions with GWAS-significant associations underlying telomere length variation, including a region that harbors the telomerase reverse transcriptase (TERT) gene. Population genomic analysis provided evidence for a selective sweep at the TERT region associated with longer telomeres. We found that telomere length is negatively correlated with flowering time variation not only in A. thaliana, but also in maize and rice, indicating a link between life-history traits and chromosome integrity. Our results point to several possible reasons for this correlation, including the possibility that longer telomeres may be more adaptive in plants that have faster developmental rates (and therefore flower earlier). Our work suggests that chromosomal structure itself might be an adaptive trait associated with plant life-history strategies.


Assuntos
Flores/fisiologia , Variação Genética , Fenômenos Fisiológicos Vegetais/genética , Telômero/genética , Arabidopsis/genética , Tamanho do Genoma , Genoma de Planta , Estudo de Associação Genômica Ampla , Oryza/genética , Seleção Genética , Sequências de Repetição em Tandem , Telomerase/genética , Fatores de Tempo , Zea mays/genética
3.
Catheter Cardiovasc Interv ; 103(4): 587-596, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38341624

RESUMO

BACKGROUND: Pulsta valve is increasingly used for percutaneous pulmonary valve implantation (PPVI) in patients with a large native right ventricular outflow tract (RVOT). This study aims to elucidate the outcomes of Pulsta valve implantation within the native RVOT and assess its adaptability to various native main pulmonary artery (PA) anatomies. METHODS: A multicenter retrospective study included 182 patients with moderate to severe pulmonary regurgitation in the native RVOT who underwent PPVI with Pulsta valves® between February 2016 and August 2023 at five Korean and Taiwanese tertiary referral centers. RESULTS: Pulsta valve implantation was successful in 179 out of 182 patients (98.4%) with an average age of 26.7 ± 11.0 years. The median follow-up duration was 29 months. Baseline assessments revealed enlarged right ventricle (RV) volume (mean indexed RV end-diastolic volume: 163.1 (interquartile range, IQR: 152.0-180.3 mL/m²), which significantly decreased to 123.6(IQR: 106.6-137.5 mL/m2  after 1 year. The main PA types were classified as pyramidal (3.8%), straight (38.5%), reverse pyramidal (13.2%), convex (26.4%), and concave (18.1%) shapes. Pulsta valve placement was adapted, with distal main PA for pyramidal shapes and proximal or mid-PA for reverse pyramidal shapes. Two patients experienced Pulsta valve embolization to RV, requiring surgical removal, and one patient encountered valve migration to the distal main PA, necessitating surgical fixation. CONCLUSIONS: Customized valve insertion sites are pivotal in self-expandable PPVI considering diverse native RVOT shape. The rather soft and compact structure of the Pulsta valve has characteristics to are adaptable to diverse native RVOT geometries.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Pulmonar , Valva Pulmonar , Humanos , Adolescente , Adulto Jovem , Adulto , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Ventrículos do Coração , Estudos Retrospectivos , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/cirurgia , Resultado do Tratamento , Insuficiência da Valva Pulmonar/diagnóstico por imagem , Insuficiência da Valva Pulmonar/etiologia , Insuficiência da Valva Pulmonar/cirurgia , Cateterismo Cardíaco
4.
World J Urol ; 42(1): 119, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446234

RESUMO

BACKGROUND: The management of patients with ureteral calculi in the emergency department (ED) remains challenging due to high revisit rates. PURPOSE: To identify predictors of revisits among patients with ureteral calculi in the ED. DESIGN, SETTING, AND PARTICIPANTS: Data from patients who presented at a tertiary academic hospital in Seoul, Republic of Korea, between February 2018 and December 2019, were analyzed retrospectively. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Variables, including the respiratory rate (RR), estimated glomerular filtration rate (eGFR), duration of pain, number of analgesic doses, location of ureteral calculi, and ED length of stay (LOS) were examined using logistic regression. We also examined some additional variables included in the STONE and CHOKAI scoring systems to examine their association with revisit. RESULTS: Significant predictors of revisits included the number of analgesic doses and the location of ureteral calculi. Patients who required multiple analgesic doses or those with proximal or mid-ureteral calculi were more likely to revisit the ED. Although the STONE and CHOKAI scores could predict uncomplicated ureteral calculi, we found that the CHOKAI score is a valuable tool for predicting the likelihood of patient revisits (p = 0.021). CONCLUSIONS: Effective pain management and consideration of calculi location are important for predicting patient revisits. More research is required to validate findings, develop precise predictive models, and empower tailored care for high-risk patients. In patients with ureteral calculi in the ED, the number of analgesics given and stone location predict return visits. Proximal ureteral calculi on CT may require early urologic intervention to prevent pain-related revisits.


Assuntos
Cálculos Ureterais , Humanos , Cálculos Ureterais/complicações , Cálculos Ureterais/terapia , Manejo da Dor , Readmissão do Paciente , Estudos Retrospectivos , Dor , Analgésicos
5.
Proc Natl Acad Sci U S A ; 118(37)2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34497122

RESUMO

Some of the most spectacular adaptive radiations begin with founder populations on remote islands. How genetically limited founder populations give rise to the striking phenotypic and ecological diversity characteristic of adaptive radiations is a paradox of evolutionary biology. We conducted an evolutionary genomics analysis of genus Metrosideros, a landscape-dominant, incipient adaptive radiation of woody plants that spans a striking range of phenotypes and environments across the Hawaiian Islands. Using nanopore-sequencing, we created a chromosome-level genome assembly for Metrosideros polymorpha var. incana and analyzed whole-genome sequences of 131 individuals from 11 taxa sampled across the islands. Demographic modeling and population genomics analyses suggested that Hawaiian Metrosideros originated from a single colonization event and subsequently spread across the archipelago following the formation of new islands. The evolutionary history of Hawaiian Metrosideros shows evidence of extensive reticulation associated with significant sharing of ancestral variation between taxa and secondarily with admixture. Taking advantage of the highly contiguous genome assembly, we investigated the genomic architecture underlying the adaptive radiation and discovered that divergent selection drove the formation of differentiation outliers in paired taxa representing early stages of speciation/divergence. Analysis of the evolutionary origins of the outlier single nucleotide polymorphisms (SNPs) showed enrichment for ancestral variations under divergent selection. Our findings suggest that Hawaiian Metrosideros possesses an unexpectedly rich pool of ancestral genetic variation, and the reassortment of these variations has fueled the island adaptive radiation.


Assuntos
Adaptação Fisiológica , Evolução Molecular , Especiação Genética , Myrtaceae/fisiologia , Polimorfismo Genético , Tolerância a Radiação , Radiação Ionizante , Genética Populacional , Myrtaceae/efeitos da radiação , Fenótipo
6.
Pediatr Cardiol ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438790

RESUMO

Ventricular septal defect (VSD) is a common congenital heart disease. However, consensus on the utility of echocardiography in predicting spontaneous closure (SC) of VSD remains lacking. This study aimed to identify and validate significant predictors of SC through a predictive scoring system. This retrospective study included medical records of 712 echocardiography instances performed on 304 patients diagnosed with VSD from 2016 to 2020 in their first year of life. A novel scoring system for predicting the SC of VSD was developed and validated using another dataset from different hospitals. Of the 304 patients, 215 (70.7%) had perimembranous (PM) VSDs and 89 had muscular (29.3%) VSDs. The median follow-up periods were 36.2 (interquartile range [IQR], 13-59) months and 13.7 9 (IQR, 5-37.4) days for PM and muscular VSDs, respectively. The overall SC rate during follow-up was 29.3%. Pulmonary hypertension (HTN), concomitant left ventricle (LV)-right atrium (RA) shunt, VSD size to aortic valve (AV) annulus size ratio, and left ventricular end-diastolic dimension (LVEDD) z-score were significant risk factors affecting SC of VSD. The "P-VSD" score, a new scoring system, demonstrated an area under the curve for predictability of 0.769. Pulmonary HTN, concomitant LV-RA shunt, LVEDD z-score, and VSD size-to-AV annulus size ratio at diagnosis were significantly associated with non-SC VSD after infancy. The P-VSD score can predict the SC of VSD in clinical settings and simplify the identification and appropriate management of high-risk patients.

7.
J Integr Neurosci ; 23(6): 122, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38940090

RESUMO

BACKGROUND: Rheum tanguticum root, cataloged as "Daehwang" in the Korean Pharmacopeia, is rich in various anthraquinones known for their anti-inflammatory and antioxidant properties. Formulations containing Daehwang are traditionally employed for treating neurological conditions. This study aimed to substantiate the antiepileptic and neuroprotective efficacy of R. tanguticum root extract (RTE) against trimethyltin (TMT)-induced epileptic seizures and hippocampal neurodegeneration. METHODS: The constituents of RTE were identified by ultra-performance liquid chromatography (UPLC). Experimental animals were grouped into the following five categories: control, TMT, and three TMT+RTE groups with dosages of 10, 30, and 100 mg/kg. Seizure severity was assessed daily for comparison between the groups. Brain tissue samples were examined to determine the extent of neurodegeneration and neuroinflammation using histological and molecular biology techniques. Network pharmacology analysis involved extracting herbal targets for Daehwang and disease targets for epilepsy from multiple databases. A protein-protein interaction network was built using the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, and pivotal targets were determined by topological analysis. Enrichment analysis was performed using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) tool to elucidate the underlying mechanisms. RESULTS: The RTE formulation was found to contain sennoside A, sennoside B, chrysophanol, emodin, physcion, (+)-catechin, and quercetin-3-O-glucuronoid. RTE effectively inhibited TMT-induced seizures at 10, 30, and 100 mg/kg dosages and attenuated hippocampal neuronal decay and neuroinflammation at 30 and 100 mg/kg dosages. Furthermore, RTE significantly reduced mRNA levels of tumor necrosis factor (TNF-α), glial fibrillary acidic protein (GFAP), and c-fos in hippocampal tissues. Network analysis revealed TNF, Interleukin-1 beta (IL-1ß), Interleukin-6 (IL-6), Protein c-fos (FOS), RAC-alpha serine/threonine-protein kinase (AKT1), and Mammalian target of rapamycin (mTOR) as the core targets. Enrichment analysis demonstrated significant involvement of R. tanguticum components in neurodegeneration (p = 4.35 × 10-5) and TNF signaling pathway (p = 9.94 × 10-5). CONCLUSIONS: The in vivo and in silico analyses performed in this study suggests that RTE can potentially modulate TMT-induced epileptic seizures and neurodegeneration. Therefore, R. tanguticum root is a promising herbal treatment option for antiepileptic and neuroprotective applications.


Assuntos
Anticonvulsivantes , Modelos Animais de Doenças , Epilepsia , Hipocampo , Fármacos Neuroprotetores , Extratos Vegetais , Raízes de Plantas , Rheum , Compostos de Trimetilestanho , Animais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/administração & dosagem , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Rheum/química , Raízes de Plantas/química , Masculino , Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Epilepsia/induzido quimicamente , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Simulação por Computador , Farmacologia em Rede , Mapas de Interação de Proteínas , Ratos
8.
Sensors (Basel) ; 24(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38610298

RESUMO

Radial pulse diagnosis is the most common method to examine the human health state in Traditional East Asian Medicine (TEAM). A cold stress-related suboptimal health state (subhealth) is often undetectable during routine medical examinations, however, it can be detected through the palpation of specific pulse waves, particularly a 'tight pulse', in TEAM. Therefore, this study examined a correlation between 'tight pulse' and vascular changes in the radial artery (RA) induced by a cold pressor trial (CPT). Twenty healthy subjects underwent sequentially control trial and CPT with room-temperature and ice-cold water, respectively, on the right forearm. The radial pulse and vascular changes were then examined on the left arm. The radial pulse scores for frequencies of 'tight pulse' with strong arterial tension increased after the CPT compared with the control trial. The pulse scores were reversely correlated with the RA thickness and volumes in ultrasonography, but not with changes in the systolic/diastolic blood pressure. The RA thickness-based vascular surface and three-dimensional images visualized a 'tight pulse' showing the vasoconstriction and bumpy-/rope-shaped vascular changes in the radial pulse diagnostic region after the CPT. These findings provide valuable insights into the potential integration of clinical radial pulse diagnosis with ultrasonography for cold-related subhealth.


Assuntos
Artéria Radial , Diagnóstico Tradicional pelo Pulso , Humanos , Resposta ao Choque Frio , Frequência Cardíaca , Temperatura Baixa
9.
Nano Lett ; 23(15): 6859-6867, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37470721

RESUMO

Nanomaterials hybridized with biological components have widespread applications. among many candidates, peptides are attractive in that their peptide sequences can self-assemble with the surface of target materials with high specificity without perturbing the intrinsic properties of nanomaterials. Here, a 1D hybrid nanomaterial was developed through self-assembly of a designed peptide. A hexagonal coiled-coil motif geometrically matched to the diameter of the inorganic nanomaterial was fabricated, whose hydrophobic surface was wrapped along the axis of the hydrophobic core of the coiled coil. Our morphological and spectroscopic analyses revealed rod-shaped, homogeneous peptide-inorganic nanomaterial complexes. Culturing embryonic stem cells on surfaces coated with this peptide-assembled single-chain atomic crystal increased the growth and adhesion of the embryonic stem cells. The hybridized nanomaterial also served as an ECM for brain organoids, accelerating the maturation of neurons. New methods to fabricate hybrid materials through peptide assembly can be applied.


Assuntos
Peptídeos , Células-Tronco Pluripotentes , Peptídeos/farmacologia , Peptídeos/química , Sequência de Aminoácidos , Neurônios , Diferenciação Celular
10.
Nano Lett ; 23(13): 6269-6275, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37099317

RESUMO

Tailoring the electrical properties of one-dimensional (1D) van der Waals (vdW) materials is desirable for their applications toward electronic devices by exploiting their unique characteristics. However, 1D vdW materials have not been extensively investigated for modulation of their electrical properties. Here we control doping levels and types of 1D vdW Nb2Pd3Se8 over a wide energy range by immersion in AuCl3 or ß-nicotinamide adenine dinucleotide (NADH) solutions, respectively. Through spectroscopic analyses and electrical characterizations, we confirm that the charges were effectively transferred to Nb2Pd3Se8, and the dopant concentration was adjusted to the immersion time. Furthermore, we make the axial p-n junction of 1D Nb2Pd3Se8 by a selective area p-doping using the AuCl3 solution, which exhibits rectifying behavior with an Iforward/Ireverse of 81 and an ideality factor of 1.2. Our findings could pave the way to more practical and functional electronic devices based on 1D vdW materials.

11.
Mol Biol Evol ; 39(9)2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36073358

RESUMO

Deleterious genetic variation is maintained in populations at low frequencies. Under a model of stabilizing selection, rare (and presumably deleterious) genetic variants are associated with increase or decrease in gene expression from some intermediate optimum. We investigate this phenomenon in a population of largely Oryza sativa ssp. indica rice landraces under normal unstressed wet and stressful drought field conditions. We include single nucleotide polymorphisms, insertion/deletion mutations, and structural variants in our analysis and find a stronger association between rare variants and gene expression outliers under the stress condition. We also show an association of the strength of this rare variant effect with linkage, gene expression levels, network connectivity, local recombination rate, and fitness consequence scores, consistent with the stabilizing selection model of gene expression.


Assuntos
Oryza , Alelos , Expressão Gênica , Variação Genética , Mutação INDEL , Oryza/genética
12.
Small ; : e2308936, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054614

RESUMO

Pulmonary arterial hypertension (PAH) is a severe medical condition characterized by elevated blood pressure in the pulmonary arteries. Nitric oxide (NO) is a gaseous signaling molecule with potent vasodilator effects; however, inhaled NO is limited in clinical practice because of the need for tracheal intubation and the toxicity of high NO concentrations. In this study, inhalable NO-releasing microspheres (NO inhalers) are fabricated to deliver nanomolar NO through a nebulizer. Two NO inhalers with distinct porous structures are prepared depending on the molecular weights of NO donors. It is confirmed that pore formation can be controlled by regulating the migration of water molecules from the external aqueous phase to the internal aqueous phase. Notably, open porous NO inhalers (OPNIs) can deliver NO deep into the lungs through a nebulizer. Furthermore, OPNIs exhibit vasodilatory and anti-inflammatory effects via sustained NO release. In conclusion, the findings suggest that OPNIs with highly porous structures have the potential to serve as tools for PAH treatment.

13.
Audiol Neurootol ; 28(4): 255-261, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36754035

RESUMO

INTRODUCTION: The Carhart notch is a well-known sign of stapes fixation. However, previous studies have reported that the Carhart notch is not specific to stapes fixation and is also present in other middle ear diseases. Therefore, this study investigated the diagnostic value of threshold gap between air conduction and bone conduction (ABG) for stapes fixation, instead of the bone conduction dip representing the Carhart notch. METHODS: A total of 199 ears that underwent exploratory tympanotomy were enrolled in this retrospective study. They were categorized into three groups according to surgical findings: stapes fixation (SF), other ossicle fixation (OF), and chain disconnection (CD). Preoperative pure-tone audiograms and impedance audiograms were compared between the groups. RESULTS: The incidence of the Carhart notch did not differ between the groups. The ABG at 2,000 Hz showed a good diagnostic performance for distinguishing between the SF and CD groups (area under the curve, AUC = 0.816, p < 0.001), but poor performance for distinguishing between the SF and OF groups (AUC = 0.662, p = 0.003). Bone conduction at 2,000 Hz showed a moderate performance for distinguishing between the SF and CD groups (AUC = 0.707, p < 0.001) and did not show statistically significant results for distinguishing between the SF and OF groups (AUC = 0.594, p = 0.080). The tympanic membrane compliance was significantly higher in the CD group than in the SF group (p = 0.001). CONCLUSIONS: The Carhart notch was not a specific finding of SF. The sensitivity and specificity of ABG ≤15 dB at 2,000 Hz for distinguishing between SF and CD were 60.4% and 89.2%, respectively. To prepare for surgical interventions in patients with conductive hearing loss but a normal tympanic membrane, clinicians should comprehensively consider these results.


Assuntos
Otosclerose , Cirurgia do Estribo , Humanos , Estribo , Otosclerose/cirurgia , Estudos Retrospectivos , Audiometria de Tons Puros/efeitos adversos , Audiometria de Tons Puros/métodos , Limiar Auditivo , Cirurgia do Estribo/métodos , Perda Auditiva Condutiva/diagnóstico , Perda Auditiva Condutiva/cirurgia , Perda Auditiva Condutiva/etiologia , Condução Óssea , Resultado do Tratamento
14.
Ear Hear ; 44(1): 223-231, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35973050

RESUMO

OBJECTIVES: Despite growing interest in the genetic contribution to cochlear implant (CI) outcomes, only a few studies with limited samples have examined the association of CI outcomes with genetic etiologies. We analyzed CI outcomes using known predictors and genetic testing results to obtain a comprehensive understanding of the impact of genetic etiologies. DESIGN: We retrospectively reviewed the medical records and images of patients who underwent cochlear implantation and genetic testing at a single tertiary medical institution, between May 2008 and December 2020. After excluding those whose speech test results were unavailable, and those in whom the implant was removed due to complications, such as infection or device failure, 203 patients were included in this study. The participants were categorized into adult (≥19 years), child (2-18 years), and infant (<24 months) groups. Outcomes were measured based on categories of auditory perception, monosyllable, disyllable, and sentence scores. For the infant group, the Infant-Toddler Meaningful Auditory Integration Scale score was used. RESULTS: Among the 203 participants, a causative genetic variant was identified in 117 (57.6%) individuals. The presence of a causative variant was significantly associated with better CI outcomes in the infant group (ß = 0.23; 95% confidence interval, 0.01 to 0.47; p = 0.044), but not in the child and adult groups. In the genetically confirmed patients without cochlear malformation, genetic variants involving the spiral ganglion was a poor prognostic factor in the child group (ß = -57.24; 95% confidence interval, -90.63 to -23.75; p = 0.004). CONCLUSIONS: The presence of known genetic etiology of hearing loss was associated with better CI outcomes in the infant group, but not in the child and adult groups. A neural-type genetic variant was a poor prognostic factor in the genetically diagnosed child subgroup without cochlear malformation. Careful genetic counseling should be performed before cochlear implantation.


Assuntos
Implante Coclear , Implantes Cocleares , Percepção da Fala , Adulto , Lactente , Humanos , Implante Coclear/métodos , Estudos Retrospectivos , Resultado do Tratamento , Testes Genéticos
15.
PLoS Genet ; 16(7): e1008872, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32673310

RESUMO

Transposable elements (TEs) are genomic parasites that selfishly replicate at the expense of host fitness. Fifty years of evolutionary studies of TEs have concentrated on the deleterious genetic effects of TEs, such as their effects on disrupting genes and regulatory sequences. However, a flurry of recent work suggests that there is another important source of TEs' harmful effects-epigenetic silencing. Host genomes typically silence TEs by the deposition of repressive epigenetic marks. While this silencing reduces the selfish replication of TEs and should benefit hosts, a picture is emerging that the epigenetic silencing of TEs triggers inadvertent spreading of repressive marks to otherwise expressed neighboring genes, ultimately jeopardizing host fitness. In this Review, we provide a long-overdue overview of the recent genome-wide evidence for the presence and prevalence of TEs' epigenetic effects, highlighting both the similarities and differences across mammals, insects, and plants. We lay out the current understanding of the functional and fitness consequences of TEs' epigenetic effects, and propose possible influences of such effects on the evolution of both hosts and TEs themselves. These unique evolutionary consequences indicate that TEs' epigenetic effect is not only a crucial component of TE biology but could also be a significant contributor to genome function and evolution.


Assuntos
Elementos de DNA Transponíveis/genética , Epigênese Genética , Evolução Molecular , Inativação Gênica , Animais , Repressão Epigenética/genética , Regulação da Expressão Gênica/genética , Insetos/genética , Mamíferos/genética , Plantas/genética
16.
Proc Natl Acad Sci U S A ; 117(20): 11109-11117, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32358189

RESUMO

Outer hair cells (OHCs) play an essential role in hearing by acting as a nonlinear amplifier which helps the cochlea detect sounds with high sensitivity and accuracy. This nonlinear sound processing generates distortion products, which can be measured as distortion-product otoacoustic emissions (DPOAEs). The OHC stereocilia that respond to sound vibrations are connected by three kinds of extracellular links: tip links that connect the taller stereocilia to shorter ones and convey force to the mechanoelectrical transduction channels, tectorial membrane-attachment crowns (TM-ACs) that connect the tallest stereocilia to one another and to the overlying TM, and horizontal top connectors (HTCs) that link adjacent stereocilia. While the tip links have been extensively studied, the roles that the other two types of links play in hearing are much less clear, largely because of a lack of suitable animal models. Here, while analyzing genetic combinations of tubby mice, we encountered models missing both HTCs and TM-ACs or HTCs alone. We found that the tubby mutation causes loss of both HTCs and TM-ACs due to a mislocalization of stereocilin, which results in OHC dysfunction leading to severe hearing loss. Intriguingly, the addition of the modifier allele modifier of tubby hearing 1 in tubby mice selectively rescues the TM-ACs but not the HTCs. Hearing is significantly rescued in these mice with robust DPOAE production, indicating an essential role of the TM-ACs but not the HTCs in normal OHC function. In contrast, the HTCs are required for the resistance of hearing to damage caused by noise stress.


Assuntos
Células Ciliadas Auditivas Externas/fisiologia , Ruído , Emissões Otoacústicas Espontâneas/fisiologia , Som , Estimulação Acústica , Animais , Células Ciliadas Auditivas Externas/citologia , Perda Auditiva , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Modelos Animais , Emissões Otoacústicas Espontâneas/genética , Estereocílios/fisiologia , Membrana Tectorial
17.
J Korean Med Sci ; 38(48): e355, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38084023

RESUMO

BACKGROUND: Mutations in mitochondrial DNA (mtDNA) are associated with several genetic disorders, including sensorineural hearing loss. However, the prevalence of mtDNA mutations in a large cohort of Korean patients with hearing loss has not yet been investigated. Thus, this study aimed to investigate the frequency of mtDNA mutations in a cohort of with pre- or post-lingual hearing loss of varying severity. METHODS: A total of 711 Korean families involving 1,099 individuals were evaluated. Six mitochondrial variants associated with deafness (MTRNR1 m.1555A>G, MTTL1 m.3243A>G, MTCO1 m.7444G>A and m.7445A>G, and MTTS1 m.7471dupC and m.7511T>C) were screened using restriction fragment length polymorphism. The prevalence of the six variants was also analyzed in a large control dataset using whole-genome sequencing data from 4,534 Korean individuals with unknown hearing phenotype. RESULTS: Overall, 12 of the 711 (1.7%) patients with hearing loss had mtDNA variants, with 10 patients from independent families positive for the MTRNR1 m.1555A>G mutation and 2 patients positive for the MTCO1 m.7444G>A mutation. The clinical characteristics of patients with the mtDNA variants were characterized by post-lingual progressive hearing loss due to the m.1555A>G variant (9 of 472; 1.9%). In addition, 18/4,534 (0.4%) of the Korean population have mitochondrial variants associated with hearing loss, predominantly the m.1555A>G variant. CONCLUSION: A significant proportion of Korean patients with hearing loss is affected by the mtDNA variants, with the m.1555A>G variant being the most prevalent. These results clarify the genetic basis of hearing loss in the Korean population and emphasize the need for genetic testing for mtDNA variants.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva , Humanos , Prevalência , Perda Auditiva Neurossensorial/epidemiologia , Perda Auditiva Neurossensorial/genética , Mutação , DNA Mitocondrial/genética , República da Coreia/epidemiologia
18.
Nano Lett ; 22(13): 5198-5206, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35728001

RESUMO

Over the past few years, many efforts have been devoted to growing single-crystal graphene due to its great potential in future applications. However, a number of issues remain for single-crystal graphene growth, such as control of nanoscale defects and the substrate-dependent nonuniformity of graphene quality. In this work, we demonstrate a possible route toward single-crystal graphene by combining aligned nucleation of graphene nanograins on Cu/Ni (111) and sequential heat treatment over pregrown graphene grains. By use of a mobile hot-wire CVD system, prealigned grains were stitched into one continuous film with up to ∼97% single-crystal domains, compared to graphene grown on polycrystalline Cu, which was predominantly high-angle tilt boundary (HATB) domains. The single-crystal-like graphene showed remarkably high thermal conductivity and carrier mobility of ∼1349 W/mK at 350 K and ∼33 600 (38 400) cm2 V-1 s-1 for electrons (holes), respectively, which indicates that the crystallinity is high due to suppression of HATB domains.

19.
Geriatr Nurs ; 53: 6-11, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37399614

RESUMO

OBJECTIVE: In this study, we compared the proportion of antibiotic resistance between patients who visited the emergency department (ED) with urinary tract infection (UTI) from long-term care hospitals (LTCH), which is a type of long-term care facilities (LTCF) and the community. We assessed the resulting difference in prognosis. METHOD: Older adults who visited the ED between January and December 2019 and were diagnosed with UTI were divided into community residents and LTCH residents. We investigated the antibiotics sensitivity rates, end of therapy (EOT), and the patient's outcomes were evaluated. RESULTS: The antibiotic resistance rate was higher in LTCH residents. LTCH residents had a higher in hospital mortality rate compared to community residents. EOT was found to be longer, and admission rate and in-hospital mortality rate were also higher in LTCH residents. CONCLUSION: LTCF residents had a higher rate of antibiotic resistance and a poor prognosis.


Assuntos
Assistência de Longa Duração , Infecções Urinárias , Humanos , Idoso , Infecções Urinárias/tratamento farmacológico , Casas de Saúde , Antibacterianos/uso terapêutico , Resistência Microbiana a Medicamentos , Hospitais , Estudos Retrospectivos
20.
Medicina (Kaunas) ; 59(8)2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37629690

RESUMO

Background and Objectives: Analysis of urine stone composition is one of the most important factors in urolithiasis treatment. This study investigated whether a convolutional neural network (CNN) can show decent results in predicting urinary stone composition even in single-use flexible ureterorenoscopic (fURS) images with relatively low resolution. Materials and Methods: This study retrospectively used surgical images from fURS lithotripsy performed by a single surgeon between January 2018 and December 2021. The ureterorenoscope was a single-use flexible ureteroscope (LithoVue, Boston Scientific). Among the images taken during surgery, a single image satisfying the inclusion and exclusion criteria was selected for each stone. Cases were divided into two groups according to whether they contained any calcium oxalate (the Calcium group) or none (the Non-calcium group). From 506 total cases, 207 stone surface images were finally included in the study. In the CNN model, the transfer learning method using Resnet-18 as a pre-trained model was used, and only endoscopic digital images and stone classification data were input to achieve minimally supervised learning. Results: There were 175 cases in the Calcium group and 32 in the Non-calcium group. After training and validation, the model was tested using the test set, and the total accuracy was 81.8%. Recall and precision of the test results were 88.2% and 88.2% in the Calcium group and 60.0% and 60.0% in the Non-calcium group, respectively. The area under the receiver operating characteristic curve of the model, which represents its classification performance, was 0.82. Conclusions: Single-use flexible ureteroscopes have financial benefits but low vision quality compared with reusable digital flexible ureteroscopes. As far as we know, this is the first artificial intelligence study using single-use fURS images. It is meaningful that the CNN performed well even under these difficult conditions because these results can further expand the possibilities of its use.


Assuntos
Cálculos Urinários , Urolitíase , Humanos , Ureteroscópios , Ureteroscopia , Inteligência Artificial , Estudos Retrospectivos , Urolitíase/cirurgia , Cálculos Urinários/cirurgia , Redes Neurais de Computação
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