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1.
Proc Natl Acad Sci U S A ; 121(16): e2322924121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38607933

RESUMO

Many Mendelian disorders, such as Huntington's disease (HD) and spinocerebellar ataxias, arise from expansions of CAG trinucleotide repeats. Despite the clear genetic causes, additional genetic factors may influence the rate of those monogenic disorders. Notably, genome-wide association studies discovered somewhat expected modifiers, particularly mismatch repair genes involved in the CAG repeat instability, impacting age at onset of HD. Strikingly, FAN1, previously unrelated to repeat instability, produced the strongest HD modification signals. Diverse FAN1 haplotypes independently modify HD, with rare genetic variants diminishing DNA binding or nuclease activity of the FAN1 protein, hastening HD onset. However, the mechanism behind the frequent and the most significant onset-delaying FAN1 haplotype lacking missense variations has remained elusive. Here, we illustrated that a microRNA acting on 3'-UTR (untranslated region) SNP rs3512, rather than transcriptional regulation, is responsible for the significant FAN1 expression quantitative trait loci signal and allelic imbalance in FAN1 messenger ribonucleic acid (mRNA), accounting for the most significant and frequent onset-delaying modifier haplotype in HD. Specifically, miR-124-3p selectively targets the reference allele at rs3512, diminishing the stability of FAN1 mRNA harboring that allele and consequently reducing its levels. Subsequent validation analyses, including the use of antagomir and 3'-UTR reporter vectors with swapped alleles, confirmed the specificity of miR-124-3p at rs3512. Together, these findings indicate that the alternative allele at rs3512 renders the FAN1 mRNA less susceptible to miR-124-3p-mediated posttranscriptional regulation, resulting in increased FAN1 levels and a subsequent delay in HD onset by mitigating CAG repeat instability.


Assuntos
Doença de Huntington , MicroRNAs , Humanos , Regiões 3' não Traduzidas/genética , Endodesoxirribonucleases , Exodesoxirribonucleases/genética , Estudo de Associação Genômica Ampla , Doença de Huntington/genética , MicroRNAs/genética , Enzimas Multifuncionais
2.
Gastroenterology ; 164(7): 1293-1309, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36898552

RESUMO

BACKGROUND & AIMS: Intrahepatic cholangiocarcinomas (iCCs) are characterized by their rarity, difficult diagnosis, and overall poor prognosis. The iCC molecular classification for developing precision medicine strategies was investigated. METHODS: Comprehensive genomic, transcriptomic, proteomic, and phosphoproteomic analyses were performed on treatment-naïve tumor samples from 102 patients with iCC who underwent surgical resection with curative intent. An organoid model was constructed for testing therapeutic potential. RESULTS: Three clinically supported subtypes (stem-like, poorly immunogenic, and metabolism) were identified. NCT-501 (aldehyde dehydrogenase 1 family member A1 [ALDH1A1] inhibitor) exhibited synergism with nanoparticle albumin-bound-paclitaxel in the organoid model for the stem-like subtype. The oncometabolite dysregulations were associated with different clinical outcomes in the stem-like and metabolism subtypes. The poorly immunogenic subtype harbors the non-T-cell tumor infiltration. Integrated multiomics analysis not only reproduced the 3 subtypes but also showed heterogeneity in iCC. CONCLUSIONS: This large-scale proteogenomic analysis provides information beyond that obtained with genomic analysis, allowing the functional impact of genomic alterations to be discerned. These findings may assist in the stratification of patients with iCC and in developing rational therapeutic strategies.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Proteogenômica , Humanos , Proteômica , Prognóstico , Colangiocarcinoma/genética , Colangiocarcinoma/cirurgia , Colangiocarcinoma/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/patologia
3.
Am J Hum Genet ; 107(1): 96-110, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32589923

RESUMO

A recent genome-wide association study of Huntington disease (HD) implicated genes involved in DNA maintenance processes as modifiers of onset, including multiple genome-wide significant signals in a chr15 region containing the DNA repair gene Fanconi-Associated Nuclease 1 (FAN1). Here, we have carried out detailed genetic, molecular, and cellular investigation of the modifiers at this locus. We find that missense changes within or near the DNA-binding domain (p.Arg507His and p.Arg377Trp) reduce FAN1's DNA-binding activity and its capacity to rescue mitomycin C-induced cytotoxicity, accounting for two infrequent onset-hastening modifier signals. We also idenified a third onset-hastening modifier signal whose mechanism of action remains uncertain but does not involve an amino acid change in FAN1. We present additional evidence that a frequent onset-delaying modifier signal does not alter FAN1 coding sequence but is associated with increased FAN1 mRNA expression in the cerebral cortex. Consistent with these findings and other cellular overexpression and/or suppression studies, knockout of FAN1 increased CAG repeat expansion in HD-induced pluripotent stem cells. Together, these studies support the process of somatic CAG repeat expansion as a therapeutic target in HD, and they clearly indicate that multiple genetic variations act by different means through FAN1 to influence HD onset in a manner that is largely additive, except in the rare circumstance that two onset-hastening alleles are present. Thus, an individual's particular combination of FAN1 haplotypes may influence their suitability for HD clinical trials, particularly if the therapeutic agent aims to reduce CAG repeat instability.


Assuntos
Endodesoxirribonucleases/genética , Exodesoxirribonucleases/genética , Doença de Huntington/genética , Enzimas Multifuncionais/genética , Linhagem Celular , Estudo de Associação Genômica Ampla/métodos , Células HEK293 , Haplótipos/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética
4.
New Phytol ; 240(2): 757-769, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37518950

RESUMO

Mitragynine, an analgesic alkaloid from the plant Mitragyna speciosa (kratom), offers a safer alternative to clinical opioids such as morphine, owing to its more favorable side effect profile. Although kratom has been traditionally used for stimulation and pain management in Southeast Asia, the mitragynine biosynthesis pathway has remained elusive. We embarked on a search for mitragynine biosynthetic genes from the transcriptomes of kratom and other members of the Rubiaceae family. We studied their functions in vitro and in vivo. Our investigations led to the identification of several reductases and an enol methyltransferase that forms a new clade within the SABATH methyltransferase family. Furthermore, we discovered a methyltransferase from Hamelia patens (firebush), which catalyzes the final step. With the tryptamine 4-hydroxylase from the psychedelic mushroom Psilocybe cubensis, we accomplished the four-step biosynthesis for mitragynine and its stereoisomer, speciogynine in both yeast and Escherichia coli when supplied with tryptamine and secologanin. Although we have yet to pinpoint the authentic hydroxylase and methyltransferase in kratom, our discovery completes the mitragynine biosynthesis. Through these breakthroughs, we achieved the microbial biosynthesis of kratom opioids for the first time. The remarkable enzyme promiscuity suggests the possibility of generating derivatives and analogs of kratom opioids in heterologous systems.


Assuntos
Mitragyna , Alcaloides de Triptamina e Secologanina , Analgésicos Opioides , Mitragyna/genética , Extratos Vegetais , Triptaminas , Oxigenases de Função Mista
5.
Exp Dermatol ; 32(12): 2048-2061, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37767872

RESUMO

The skin is the largest organ in the human body, and histologically consists of the epidermis, dermis and subcutaneous tissue. Humans maintain a cooperative symbiotic relationship with their skin microbiota, a complex community of bacteria, fungi and viruses that live on the surface of the skin, and which act as a barrier to protect the body from the inside and outside. The skin is a 'habitat' and vast 'ecosystem' inhabited by countless microbes; as such, relationships have been forged through millions of years of coevolution. It is not surprising then that microbes are key participants in shaping and maintaining essential physiological processes. In addition to maintaining barrier function, the unique symbiotic microbiota that colonizes the skin increases the immune response and provides protection against pathogenic microbes. This review examines our current understanding of skin microbes in shaping and enhancing the skin barrier, as well as skin microbiome-host interactions and their roles in skin diseases, such as atopic dermatitis (AD). We also report on the current status of AD therapeutic drugs that target the skin microbiome, related research on current therapeutic strategies, and the limitations and future considerations of skin microbiome research. In particular, as a future strategy, we discuss the need for a skin-on-a-chip-based microphysiological system research model amenable to biomimetic in vitro studies and human skin equivalent models, including skin appendages.


Assuntos
Dermatite Atópica , Microbiota , Dermatopatias , Humanos , Pele/patologia , Dermatopatias/patologia , Epiderme/patologia
6.
Int J Mol Sci ; 24(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37108676

RESUMO

Cholangiocarcinoma is a malignant epithelial tumor arising from bile ducts that is frequently fatal. Diagnosis is difficult due to tumor location in the biliary tract. Earlier diagnosis requires less invasive methods of identifying effective biomarkers for cholangiocarcinoma. The present study investigated the genomic profiles of cell-free DNA (cfDNA) and DNA from corresponding primary cholangiocarcinomas using a targeted sequencing panel. Somatic mutations in primary tumor DNA and circulating tumor DNA (ctDNA) were compared and clinical applications of ctDNA validated in patients with cholangiocarcinoma. A comparison of primary tumor DNA and ctDNA identified somatic mutations in patients with early cholangiocarcinomas that showed clinical feasibility for early screening. The predictive value of single-nucleotide variants (SNVs) of preoperative plasma cfDNA positive for somatic mutations of the primary tumor was 42%. The sensitivity and specificity of postoperative plasma SNVs in detecting clinical recurrence were 44% and 45%, respectively. Targetable fibroblast growth factor receptor 2 (FGFR2) and Kirsten rat sarcoma virus (KRAS) mutations were detected in 5% of ctDNA samples from patients with cholangiocarcinoma. These findings showed that genomic profiling of cfDNA was useful in clinical evaluation, although ctDNA had limited ability to detect mutations in cholangiocarcinoma patients. Serial monitoring of ctDNA is important clinically and in assessing real-time molecular aberrations in cholangiocarcinoma patients.


Assuntos
Neoplasias dos Ductos Biliares , Ácidos Nucleicos Livres , Colangiocarcinoma , DNA Tumoral Circulante , Humanos , DNA Tumoral Circulante/genética , Biomarcadores Tumorais/genética , DNA de Neoplasias/genética , Ácidos Nucleicos Livres/genética , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/genética , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Mutação , Sequenciamento de Nucleotídeos em Larga Escala/métodos
7.
BMC Nurs ; 22(1): 297, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37653385

RESUMO

BACKGROUND: Competency in infection control is crucial for implementing nursing best practices to ensure patient safety. However, research is lacking on the infection control education received by nursing students prior to entering clinical settings as nurses. This study aimed to explore how nursing students conceptualize infection control care in undergraduate nursing programs. METHODS: This study employed a qualitative research method using phenomenography. Universities providing undergraduate nursing programs in Korea. Thirty nursing students: 10 students each from the 2nd, 3rd, and 4th years of five undergraduate programs. Data were collected from May 2019 to February 2020 through semi-structured interviews and analyzed using a phenomenographic analysis procedure. RESULTS: Six descriptive categories were derived inductively for nursing students' frames of reference regarding infection control care and six descriptive categories of how nursing students learned about infection control care. The structural framework of the identified categories, about how nursing students learn about infection control care, was presented as an outcome space. CONCLUSIONS: Given that nursing students demonstrate diverse conceptualizations of infection control and are at varying levels of learning, professors and clinical mentors need to develop theoretical education and clinical practice opportunities that consider these differences.

8.
Hum Mol Genet ; 29(18): 3044-3053, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-32876667

RESUMO

Recent genome-wide association studies of age-at-onset in Huntington's disease (HD) point to distinct modes of potential disease modification: altering the rate of somatic expansion of the HTT CAG repeat or altering the resulting CAG threshold length-triggered toxicity process. Here, we evaluated the mouse orthologs of two HD age-at-onset modifier genes, FAN1 and RRM2B, for an influence on somatic instability of the expanded CAG repeat in Htt CAG knock-in mice. Fan1 knock-out increased somatic expansion of Htt CAG repeats, in the juvenile- and the adult-onset HD ranges, whereas knock-out of Rrm2b did not greatly alter somatic Htt CAG repeat instability. Simultaneous knock-out of Mlh1, the ortholog of a third HD age-at-onset modifier gene (MLH1), which suppresses somatic expansion of the Htt knock-in CAG repeat, blocked the Fan1 knock-out-induced acceleration of somatic CAG expansion. This genetic interaction indicates that functional MLH1 is required for the CAG repeat destabilizing effect of FAN1 loss. Thus, in HD, it is uncertain whether the RRM2B modifier effect on timing of onset may be due to a DNA instability mechanism. In contrast, the FAN1 modifier effects reveal that functional FAN1 acts to suppress somatic CAG repeat expansion, likely in genetic interaction with other DNA instability modifiers whose combined effects can hasten or delay onset and other CAG repeat length-driven phenotypes.


Assuntos
Proteínas de Ciclo Celular/genética , Endodesoxirribonucleases/genética , Exodesoxirribonucleases/genética , Proteína Huntingtina/genética , Doença de Huntington/genética , Enzimas Multifuncionais/genética , Proteína 1 Homóloga a MutL/genética , Ribonucleotídeo Redutases/genética , Idade de Início , Animais , Modelos Animais de Doenças , Genes Modificadores/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Doença de Huntington/patologia , Camundongos , Camundongos Knockout , Fenótipo , Expansão das Repetições de Trinucleotídeos/genética
9.
New Phytol ; 235(2): 743-758, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35403705

RESUMO

Hybridization and polyploidization are pivotal to plant evolution. Genetic crosses between distantly related species are rare in nature due to reproductive barriers but how such hurdles can be overcome is largely unknown. Here we report the hybrid genome structure of xBrassicoraphanus, a synthetic allotetraploid of Brassica rapa and Raphanus sativus. We performed cytogenetic analysis and de novo genome assembly to examine chromosome behaviors and genome integrity in the hybrid. Transcriptome analysis was conducted to investigate expression of duplicated genes in conjunction with epigenome analysis to address whether genome admixture entails epigenetic reconfiguration. Allotetraploid xBrassicoraphanus retains both parental chromosomes without genome rearrangement. Meiotic synapsis formation and chromosome exchange are avoided between nonhomologous progenitor chromosomes. Reconfiguration of transcription network occurs, and less divergent cis-elements of duplicated genes are associated with convergent expression. Genome-wide DNA methylation asymmetry between progenitors is largely maintained but, notably, B. rapa-originated transposable elements are transcriptionally silenced in xBrassicoraphanus through gain of DNA methylation. Our results demonstrate that hybrid genome stabilization and transcription compatibility necessitate epigenome landscape adjustment and rewiring of cis-trans interactions. Overall, this study suggests that a certain extent of genome divergence facilitates hybridization across species, which may explain the great diversification and expansion of angiosperms during evolution.


Assuntos
Brassicaceae , Genoma de Planta , Brassicaceae/genética , Metilação de DNA/genética , Hibridização Genética
10.
Biomacromolecules ; 23(4): 1652-1661, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35312288

RESUMO

With the ability to design their sequences and structures, peptides can be engineered to realize a wide variety of functionalities and structures. Herein, computational design was used to identify a set of 17 peptides having a wide range of putative charge states but the same tetrameric coiled-coil bundle structure. Calculations were performed to identify suitable locations for ionizable residues (D, E, K, and R) at the bundle's exterior sites, while interior hydrophobic interactions were retained. The designed bundle structures spanned putative charge states of -32 to +32 in units of electron charge. The peptides were experimentally investigated using spectroscopic and scattering techniques. Thermal stabilities of the bundles were investigated using circular dichroism. Molecular dynamics simulations assessed structural fluctuations within the bundles. The cylindrical peptide bundles, 4 nm long by 2 nm in diameter, were covalently linked to form rigid, micron-scale polymers and characterized using transmission electron microscopy. The designed suite of sequences provides a set of readily realized nanometer-scale structures of tunable charge that can also be polymerized to yield rigid-rod polyelectrolytes.


Assuntos
Peptídeos , Polímeros , Dicroísmo Circular , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular , Peptídeos/química , Polímeros/química
11.
Curr Cardiol Rep ; 24(11): 1547-1555, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36048306

RESUMO

PURPOSE OF REVIEW: Artificial intelligence (AI) techniques have the potential to remarkably change the practice of cardiology in order to improve and optimize outcomes in heart failure and specifically cardiomyopathies, offering us novel tools to interpret data and make clinical decisions. The aim of this review is to describe the contemporary state of AI and digital health applied to cardiomyopathies as well as to define a potential pivotal role of its application by physicians in clinical practice. RECENT FINDINGS: Many studies have been undertaken in recent years on cardiomyopathy screening especially using AI-enhanced electrocardiography (ECG). Even with mild left ventricular (LV) dysfunction, AI-ECG screening for amyloidosis, hypertrophic cardiomyopathy, or dilated cardiomyopathy is now feasible. Introduction of AI-ECG in routine clinical care has resulted in higher detection of LV systolic dysfunction; however, clinical research on a broader scale with diverse populations is necessary and ongoing. In the area of cardiac-imaging, AI automatically assesses the thickness and characteristics of myocardium to differentiate cardiomyopathies, but research on its prognostic capability has yet to be conducted. AI is also being applied to cardiomyopathy genomics, especially to predict pathogenicity of variants and identify whether these variants are clinically actionable. While the implementation of AI in the diagnosis and treatment of cardiomyopathies is still in its infancy, an ever-growing clinical research strategy will ascertain the clinical utility of these AI tools to help improve diagnosis of and outcomes in cardiomyopathies. We also need to standardize the tools used to monitor the performance of AI-based systems which can then be used to expedite decision-making and rectify any hidden biases. Given its potential important role in clinical practice, healthcare providers need to familiarize themselves with the promise and limitations of this technology.


Assuntos
Inteligência Artificial , Cardiomiopatias , Humanos , Genômica , Cardiomiopatias/diagnóstico
12.
Int J Mol Sci ; 23(4)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35216228

RESUMO

Currently, the mechanism of progression of atopic dermatitis (AD) is not well understood because there is no physiologically appropriate disease model in terms of disease complexity and multifactoriality. Type 2 inflammation, mediated by interleukin (IL)-4 and IL-13, plays an important role in AD. In this study, full-thickness human skin equivalents consisting of human-derived cells were fabricated from pumpless microfluidic chips and stimulated with IL-4 and IL-13. The morphological properties, gene expression, cytokine secretion and protein expression of the stimulated human skin equivalent (HSE) epidermis were investigated. The results showed epidermal and spongy formations similar to those observed in lesions in AD, and decreased expression of barrier-related filaggrin, loricrin and involucrin genes and proteins induced by IL-4Rα signaling. In addition, we induced the expression of carbonic anhydrase II (CAII), a gene specifically expressed in the epidermis of patients with AD. Thus, AD human skin equivalents can be used to mimic the key pathological features of atopic dermatitis, overcoming the limitations of existing studies that rely solely on mouse models and have been unable to translate their effects to humans. Our results will be useful for future research on the development of therapeutic agents for atopic dermatitis.


Assuntos
Dermatite Atópica/metabolismo , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Pele/metabolismo , Animais , Dermatite Atópica/tratamento farmacológico , Eczema/tratamento farmacológico , Eczema/metabolismo , Eczema/patologia , Epiderme/efeitos dos fármacos , Epiderme/metabolismo , Epiderme/patologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/patologia , Dispositivos Lab-On-A-Chip , Proteínas de Membrana/farmacologia , Ratos , Pele/efeitos dos fármacos , Pele/patologia
13.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362303

RESUMO

Indole-3-lactic acid (I3LA) is a well-known metabolite involved in tryptophan metabolism. Indole derivatives are involved in the differentiation of immune cells and the synthesis of cytokines via the aryl hydrocarbon receptors for modulating immunity, and the indole derivatives may be involved in allergic responses. I3LA was selected as a candidate substance for the treatment of atopic dermatitis (AD), and its inhibitory effect on AD progression was investigated. Full-thickness human skin equivalents (HSEs) consisting of human-derived cells were generated on microfluidic chips and stimulated with major AD-inducing factors. The induced AD-HSEs were treated with I3LA for 7 days, and this affected the AD-associated genetic biomarkers and increased the expression of the major constituent proteins of the skin barrier. After the treatment for 14 days, the surface became rough and sloughed off, and there was no significant difference between the increased AD-related mRNA expression and the skin barrier protein expression. Therefore, the short-term use of I3LA for approximately one week is considered to be effective in suppressing AD.


Assuntos
Dermatite Atópica , Humanos , Interleucina-13/metabolismo , Triptofano/farmacologia , Triptofano/metabolismo , Interleucina-4/metabolismo , Células Th2 , Pele/metabolismo , Indóis/farmacologia , Indóis/metabolismo , Citocinas/metabolismo
14.
Molecules ; 27(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36234876

RESUMO

Agastache rugosa (baechohyang) is one of the most important aromatic plants native to the Republic of Korea. A. rugosa fragrance has been used to prepare incense since the Goryeo Dynasty in Korea. The present study aimed to explore the variation in the composition of essential oils from A. rugosa among native populations in Korea. The seeds of A. rugosa were collected from 90 different sites in Korea and seedlings were raised in the nursery. Essential oils were extracted from these populations by the steam distillation extraction method and their chemical compositions were analyzed by GC-MS. The yield of essential oils of A. rugosa ranged between 0.11% and 0.86%. A total of 204 components were identified from 90 populations of A. rugosa. Out of 204 components, 32 components were common in more than 40 individuals of A. rugosa and these 32 components were selected for principal component analysis (PCA). On the basis of the essential oil compositions, six chemotypes-estragole, pulegone, methyl eugenol, menthone, isopulegone, and nepetalactone-were distinguished according to their major components. As a result of the cluster analysis, 90 individuals of A. rugosa could be classified into three groups: estragole, methyl eugenol, and pulegone. A. rugosa exhibited significant chemical diversity among the individuals. The distribution of chemotypes is associated with the collection of seeds, suggesting that genetic diversity may influence the variations in the chemical compositions and concentrations within the species. This chemical diversity serves as the background to select cultivars for the cultivation and industrial applications of A. rugosa cultivars with high essential oil yield and concentration of its chemical components.


Assuntos
Agastache , Mentha , Óleos Voláteis , Agastache/química , Derivados de Alilbenzenos , Anisóis , Monoterpenos Cicloexânicos , Eugenol/análogos & derivados , Humanos , Óleos Voláteis/química , Vapor
15.
Physiol Rev ; 94(3): 951-86, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24987009

RESUMO

Much is known about the mechanotransducer (MT) channels mediating transduction in hair cells of the vertrbrate inner ear. With the use of isolated preparations, it is experimentally feasible to deliver precise mechanical stimuli to individual cells and record the ensuing transducer currents. This approach has shown that small (1-100 nm) deflections of the hair-cell stereociliary bundle are transmitted via interciliary tip links to open MT channels at the tops of the stereocilia. These channels are cation-permeable with a high selectivity for Ca(2+); two channels are thought to be localized at the lower end of the tip link, each with a large single-channel conductance that increases from the low- to high-frequency end of the cochlea. Ca(2+) influx through open channels regulates their resting open probability, which may contribute to setting the hair cell resting potential in vivo. Ca(2+) also controls transducer fast adaptation and force generation by the hair bundle, the two coupled processes increasing in speed from cochlear apex to base. The molecular intricacy of the stereocilary bundle and the transduction apparatus is reflected by the large number of single-gene mutations that are linked to sensorineural deafness, especially those in Usher syndrome. Studies of such mutants have led to the discovery of many of the molecules of the transduction complex, including the tip link and its attachments to the stereociliary core. However, the MT channel protein is still not firmly identified, nor is it known whether the channel is activated by force delivered through accessory proteins or by deformation of the lipid bilayer.


Assuntos
Células Ciliadas Auditivas/fisiologia , Audição/fisiologia , Mecanotransdução Celular , Animais , Humanos
16.
J Am Chem Soc ; 143(31): 12315-12327, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34324336

RESUMO

Efficient viral or nonviral delivery of nucleic acids is the key step of genetic nanomedicine. Both viral and synthetic vectors have been successfully employed for genetic delivery with recent examples being DNA, adenoviral, and mRNA-based Covid-19 vaccines. Viral vectors can be target specific and very efficient but can also mediate severe immune response, cell toxicity, and mutations. Four-component lipid nanoparticles (LNPs) containing ionizable lipids, phospholipids, cholesterol for mechanical properties, and PEG-conjugated lipid for stability represent the current leading nonviral vectors for mRNA. However, the segregation of the neutral ionizable lipid as droplets in the core of the LNP, the "PEG dilemma", and the stability at only very low temperatures limit their efficiency. Here, we report the development of a one-component multifunctional ionizable amphiphilic Janus dendrimer (IAJD) delivery system for mRNA that exhibits high activity at a low concentration of ionizable amines organized in a sequence-defined arrangement. Six libraries containing 54 sequence-defined IAJDs were synthesized by an accelerated modular-orthogonal methodology and coassembled with mRNA into dendrimersome nanoparticles (DNPs) by a simple injection method rather than by the complex microfluidic technology often used for LNPs. Forty four (81%) showed activity in vitro and 31 (57%) in vivo. Some, exhibiting organ specificity, are stable at 5 °C and demonstrated higher transfection efficiency than positive control experiments in vitro and in vivo. Aside from practical applications, this proof of concept will help elucidate the mechanisms of packaging and release of mRNA from DNPs as a function of ionizable amine concentration, their sequence, and constitutional isomerism of IAJDs.


Assuntos
Dendrímeros/química , Portadores de Fármacos/química , Nanopartículas/química , RNA Mensageiro/metabolismo , Tensoativos/química , Animais , Dendrímeros/síntese química , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Estudo de Prova de Conceito , Tensoativos/síntese química
17.
BMC Cardiovasc Disord ; 21(1): 251, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34020593

RESUMO

BACKGROUND: Patients with acute myocardial infarction (AMI) are usually treated with angiotensin-converting enzyme inhibitors (ACEIs), or angiotensin receptor blockers (ARBs) if ACEIs are not tolerated. However, there is no data regarding the impact of switching from ACEIs to ARBs on long-term clinical outcomes in AMI patients with preserved left ventricular (LV) systolic function especially beyond 1 year. To investigate the effectiveness of treatment with ACEIs or ARBs on clinical outcomes over 3 years in AMI patients with preserved LV systolic function following percutaneous coronary intervention. METHOD: It is a prospective cohort study using data from a nationwide large scale registry with 53 hospitals involved in treatment of acute myocardial infarction (AMI) in Korea. Between March 2011 and September 2015, we enrolled 6236 patients with AMI who underwent primary percutaneous coronary intervention and had a left ventricular ejection fraction ≥ 50%. Main outcome measures composite of total death or recurrent AMI over 3 years after AMI. Patients were divided into an ACEI group (n = 2945), ARB group (n = 2197), or no renin-angiotensin system inhibitor (RASI) treatment (n = 1094). We analyzed patients who changed treatment. Inverse probability of treatment weighting (IPTW) analysis was also performed. RESULTS: After the adjustment with inverse probability weighting, the primary endpoints at 1 year, AMI patients receiving ACEIs showed overall better outcomes than ARBs [ARBs hazard ratio (HR) compared with ACEIs 1.384, 95% confidence interval (CI) 1.15-1.71; P = 0.003]. However, 33% of patients receiving ACEIs switched to ARBs during the first year, while only about 1.5% switched from ARBs to ACEIs. When landmark analysis was performed from 1 year to the end of the study, RASI group showed a 31% adjusted reduction in primary endpoint compared to patients with no RASI group (HR, 0.74; 95% CI 0.56-0.97; P = 0.012). CONCLUSIONS: This result suggests that certain patients got benefit from treatment with ACEIs in the first year if tolerated, but switching to ARBs beyond the first year produced similar outcomes. RASI beyond the first year reduced death or recurrent AMI in AMI patients with preserved LV systolic function. CRIS Registration number: KCT0004990.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Sistema Renina-Angiotensina/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos , Idoso , Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Substituição de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Estudos Prospectivos , Recidiva , Sistema de Registros , República da Coreia , Medição de Risco , Fatores de Risco , Sístole , Fatores de Tempo , Resultado do Tratamento
18.
Heart Vessels ; 36(10): 1514-1524, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33687543

RESUMO

Peripheral arterial disease (PAD) and heart failure share common risks and are associated with increased morbidity and mortality. However, it is unknown whether cardiac function can be an independent predictor of long-term mortality in patients with PAD. In total, 902 patients who underwent percutaneous transluminal angioplasty for PAD were enrolled. The patients were categorized into three groups according to the left ventricular ejection fraction (LVEF): reduced EF (< 40%, n = 62); mid-range EF (40-49%, n = 76); and preserved EF (≥ 50%, n = 764). Echocardiographic (EF, ratio of mitral inflow velocity to annular velocity E/e' ≥ 15, and others) and clinical parameters were tested using stepwise logistic regression analysis to determine independent predictors of 5-year mortality. A higher proportion of patients with reduced EF had ischemic heart disease than those with preserved EF (77.4% vs. 56.8%, p < 0.001). Up to 5 years, patients with reduced EF and mid-range EF showed a higher incidence of total death than those with normal EF. However, there was no difference in the incidence of myocardial infarction, stroke, and revascularization among the three groups. After multivariable adjustment, the ratio of E/e' ≥ 15 was the only strong predictor of total mortality (hazard ratio 6.14; 95% confidence interval 3.7-10.1; p < 0.01). Patients with PAD and reduced EF undergoing PTA had a higher incidence of total death during the 5-year follow-up. Initial tissue Doppler E/e' ≥ 15, a non-invasive estimate of left atrial filling pressure, was the only independent predictor of long-term mortality. The relationship between PAD and HF.


Assuntos
Doença Arterial Periférica , Angioplastia , Diástole , Ecocardiografia , Insuficiência Cardíaca/terapia , Humanos , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia , Volume Sistólico , Disfunção Ventricular Esquerda , Função Ventricular Esquerda
19.
Ann Noninvasive Electrocardiol ; 26(3): e12839, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33719135

RESUMO

INTRODUCTION: The detection and monitoring of electrolyte imbalance is essential for appropriate management of many metabolic diseases; however, there is no tool that detects such imbalances reliably and noninvasively. In this study, we developed a deep learning model (DLM) using electrocardiography (ECG) for detecting electrolyte imbalance and validated its performance in a multicenter study. METHODS AND RESULTS: This retrospective cohort study included two hospitals: 92,140 patients who underwent a laboratory electrolyte examination and an ECG within 30 min were included in this study. A DLM was developed using 83,449 ECGs of 48,356 patients; the internal validation included 12,091 ECGs of 12,091 patients. We conducted an external validation with 31,693 ECGs of 31,693 patients from another hospital, and the result was electrolyte imbalance detection. During internal, the area under the receiving operating characteristic curve (AUC) of a DLM using a 12-lead ECG for detecting hyperkalemia, hypokalemia, hypernatremia, hyponatremia, hypercalcemia, and hypocalcemia were 0.945, 0.866, 0.944, 0.885, 0.905, and 0.901, respectively. The values during external validation of the AUC of hyperkalemia, hypokalemia, hypernatremia, hyponatremia, hypercalcemia, and hypocalcemia were 0.873, 0.857, 0.839, 0.856, 0.831, and 0.813 respectively. The DLM helped to visualize the important ECG region for detecting each electrolyte imbalance, and it showed how the P wave, QRS complex, or T wave differs in importance in detecting each electrolyte imbalance. CONCLUSION: The proposed DLM demonstrated high performance in detecting electrolyte imbalance. These results suggest that a DLM can be used for detecting and monitoring electrolyte imbalance using ECG on a daily basis.


Assuntos
Inteligência Artificial , Eletrocardiografia/métodos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Desequilíbrio Hidroeletrolítico/diagnóstico
20.
BMC Geriatr ; 21(1): 160, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33663416

RESUMO

BACKGROUND: Studies reported the relationship between behavioural and psychological symptoms of dementia (BPSD), cognitive function, caregiver burden, and therapeutic effects. However, the causal relationship between BPSD in community-dwelling patients with Alzheimer's disease (AD) and caregiver burden is yet to be established. This study aimed to classify BPSD in patients with AD and identify the relationship between BPSD and the factors affecting family caregiver burden. METHODS: Path analysis was conducted at a neurology outpatient clinic of a tertiary general hospital in South Korea. The medical records of 170 patients, aged ≥50 years, diagnosed with or suspected for AD were retrospectively reviewed. We investigated cognitive function (Korean version of the Mini-Mental-State Exam), dementia stages (Korean version of the Expanded Clinical Dementia Rating scale), depression (Short-form Geriatric Depression Scale-Korea), activities of daily living (ADL; Korean version of the Barthel Activities of Daily Living index), instrumental activities of daily living (IADL; Seoul-Instrumental Activities of Daily Living), and BPSD and caregiver burden (Korean Neuropsychiatric Inventory). Considering the characteristic features of BPSD with various symptoms, BPSD was classified using factor analysis. Factor extraction was performed using principal component analysis, followed by Varimax factor rotation. RESULTS: Mean total BPSD score was 17.66 ± 20.67, and the mean score for family caregiver burden was 9.65 ± 11.12. Symptom cluster-1 (hyperactivity symptoms) included disinhibition, irritability, and agitation/aggression. Symptom cluster-2 (psychosis symptoms) included hallucinations, anxiety, elation/euphoria, delusions, and depression/dysphoria. Symptom cluster-3 (physical behaviour symptoms) included appetite and eating abnormalities, apathy/indifference, aberrant motor behaviour, sleep, and night-time behaviour disturbances. Dementia stages, ADL, and IADL had indirect effects on family caregiver burden through hyperactivity, psychosis, and physical behaviour symptoms, indicating that BPSD exerted a complete mediating effect. CONCLUSIONS: Unlike previous studies, we classified BPSD symptoms into similar symptom clusters to evaluate its effect on caregiver burden, rather than collectively investigating the 12 symptoms of BPSD. As the dementia stage worsens, symptom clusters in BPSD serve as a medium between ADL and IADL degradation and for the increase in caregivers' burden. The development and implementation of therapeutic, nursing interventions, and policies focusing on dementia stages, ADL, and IADL, delaying and preventing BPSD can alleviate family caregivers' burden.


Assuntos
Doença de Alzheimer , Demência , Atividades Cotidianas , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/terapia , Sobrecarga do Cuidador , Cuidadores , Demência/diagnóstico , Humanos , Escalas de Graduação Psiquiátrica , República da Coreia , Estudos Retrospectivos
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