RESUMEN
Streptomyces bingchenggensis is an industrial producer of milbemycins, which are important anthelmintic and insecticidal agents. Two-component systems (TCSs), which are typically situated in the same operon and are composed of a histidine kinase and a response regulator, are the predominant signal transduction pathways involved in the regulation of secondary metabolism in Streptomyces. Here, an atypical TCS, AtcR/AtcK, in which the encoding genes (sbi_06838/sbi_06839) are organized in a head-to-head pair, was demonstrated to be indispensable for the biosynthesis of multiple secondary metabolites in S. bingchenggensis. With the null TCS mutants, the production of milbemycin and yellow compound was abolished but nanchangmycin was overproduced. Transcriptional analysis and electrophoretic mobility shift assays showed that AtcR regulated the biosynthesis of these three secondary metabolites by a MilR3-mediated cascade. First, AtcR was activated by phosphorylation from signal-triggered AtcK. Second, the activated AtcR promoted the transcription of milR3. Third, MilR3 specifically activated the transcription of downstream genes from milbemycin and yellow compound biosynthetic gene clusters (BGCs) and nanR4 from the nanchangmycin BGC. Finally, because NanR4 is a specific repressor in the nanchangmycin BGC, activation of MilR3 downstream genes led to the production of yellow compound and milbemycin but inhibited nanchangmycin production. By rewiring the regulatory cascade, two strains were obtained, the yield of nanchangmycin was improved by 45-fold to 6.08 g/L and the production of milbemycin was increased twofold to 1.34 g/L. This work has broadened our knowledge on atypical TCSs and provided practical strategies to engineer strains for the production of secondary metabolites in Streptomyces.IMPORTANCEStreptomyces bingchenggensis is an important industrial strain that produces milbemycins. Two-component systems (TCSs), which consist of a histidine kinase and a response regulator, are the predominant signal transduction pathways involved in the regulation of secondary metabolism in Streptomyces. Coupled encoding genes of TCSs are typically situated in the same operon. Here, TCSs with encoding genes situated in separate head-to-head neighbor operons were labeled atypical TCSs. It was found that the atypical TCS AtcR/AtcK played an indispensable role in the biosynthesis of milbemycin, yellow compound, and nanchangmycin in S. bingchenggensis. This atypical TCS regulated the biosynthesis of specialized metabolites in a cascade mediated via a cluster-situated regulator, MilR3. Through rewiring the regulatory pathways, strains were successfully engineered to overproduce milbemycin and nanchangmycin. To the best of our knowledge, this is the first report on atypical TCS, in which the encoding genes of RR and HK were situated in separate head-to-head neighbor operons, involved in secondary metabolism. In addition, data mining showed that atypical TCSs were widely distributed in actinobacteria.
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Éteres , Macrólidos , Compuestos de Espiro , Streptomyces , Histidina Quinasa/metabolismo , Streptomyces/genética , Proteínas Bacterianas/genéticaRESUMEN
We report a targeted prodrug delivery platform that can deliver a cytostatic nucleobase analog with high drug loading. We chose fluorouracil (5FU), a drug used to treat various cancers, whose active metabolite 5-fluorodeoxyuridine monophosphate (5-FdUMP) is the antineoplastic agent. We use terminal deoxynucleotidyl transferase (TdT) to polymerize 5-fluorodeoxyuridine triphosphate (5-FdUTP) onto the 3'-end of an aptamer. We find that (i) addition of hydrophobic, unnatural nucleotides at the 3'-end of the 5-FdU polynucleotide by TdT leads to their spontaneous self-assembly into nuclease resistant micelles, (ii) aptamers presented on the micelle corona retain specificity for their cognate receptor on tumor cells, and (iii) the micelles deliver 5FU to tumor cells and exhibit greater cytotoxicity than the free drug. The modular design of our platform, consisting of a targeting moiety, a polynucleotide drug, and a self-assembly domain, can be adapted to encompass a range of polymerizable therapeutic nucleotides and targeting units.
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Antineoplásicos , Nanopartículas , Micelas , Polinucleótidos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Fluorouracilo , Nanopartículas/química , Sistemas de Liberación de Medicamentos , Línea Celular TumoralRESUMEN
It is now generally believed that elderly may have slightly higher dietary protein requirements than those of the young-middle-aged adults. We have previously conducted related studies by the indicator amino acid oxidation (IAAO) technique, but more research data are needed to revise the protein requirements of the elderly. The main objective was to reevaluate the dietary protein requirements of healthy Chinese adults (65-80 years) without sarcopenia by using the IAAO technique. Nine healthy adult men and seven healthy adult women participated in the study, with protein intakes ranging from 0·1 to 1·8 g/(kg·d). Diets that delivered energy at a 1·5 resting energy expenditure were isocaloric. The amounts of phenylalanine and tyrosine needed to remain constant for each protein dosage. By applying a nonlinear mixed-effects model analysis on the F13CO2 data, which revealed a breakpoint in F13CO2 in response to graded protein intakes, the mean protein requirement was calculated. The mean estimated average requirement (EAR) for healthy elderly Chinese adults without sarcopenia was determined to be 0·94 g/(kg·d). The protein recommended nutrient intake (RNI) determined using various derivation approaches ranged from 1·13 to 1·36 g/(kg·d). The EAR for Chinese adults without sarcopenia aged 65-80 years in this study is 6·8 % higher than the current recommended EAR (0·88 g/(kg·d)). The RNI derived using various derivation approaches are all greater than the current RNI (0·98 g/(kg·d)). This trial was registered with the Chinese clinical trial registry as ChiCTR2200061382.
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Aminoácidos , Sarcopenia , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aminoácidos/metabolismo , Dióxido de Carbono , Isótopos de Carbono , China , Proteínas en la Dieta , Necesidades Nutricionales , Oxidación-ReducciónRESUMEN
OBJECTIVE: To evaluate the changes in protein requirements of the elderly during the past five years. METHODS: Based on the previous study of protein requirements of 14 elderly in 2017, 4 of these elderly(70-80 y) were included as study participants and protein requirements were re-evaluated using the indicator amino acid oxidation method. There were seven protein levels: 0.1, 0.3, 0.6, 0.9, 1.2, 1.5 and 1.8 g/(kg·d). Maintenance diets were given for the first two days of each protein level. A stable isotope study was conducted on the day 3, using L-~(13)C-phenylalanine as an indicator on the basis of an amino acid rationed diet, which was orally ingested into the body along with the amino acid rationed diet, and breath and urine samples were collected when the metabolism of L-~(13)C-phenylalanine reached steady state in the body. By measuring the kinetic parameters of labeled amino acids in the samples, a nonlinear mixed-effects model was constructed for the protein intake to be tested and the oxidation rate of labeled amino acids. The mean protein requirement of the study population was determined by the protein intake corresponding to the inflection point of the curve. RESULTS: Based on the production rate of ~(13)CO_2 in exhaled breath of four elderly people at different protein levels, the mean protein requirement was 1.05(95%CI 0.51-1.60) g/(kg·d). The protein recommended nutrient intake was 1.31(95%CI 0.64-2.00) g/(kg·d) was estimated by applying the coefficient of variation of the mean protein requirement to derive the recommended nutrient intake. CONCLUSION: Protein requirements in the elderly have increased over a five-year period and sarcopenia may be the main cause of increased protein requirements.
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Aminoácidos , Proteínas en la Dieta , Humanos , Anciano , Isótopos de Carbono , Oxidación-Reducción , Fenilalanina/química , Fenilalanina/metabolismo , Necesidades NutricionalesRESUMEN
PURPOSE: The aim of this study was to describe the clinical impact of commercial laboratories issuing conflicting classifications of genetic variants. METHODS: Results from 2000 patients undergoing a multigene hereditary cancer panel by a single laboratory were analyzed. Clinically significant discrepancies between the laboratory-provided test reports and other major commercial laboratories were identified, including differences between pathogenic/likely pathogenic and variant of uncertain significance (VUS) classifications, via review of ClinVar archives. For patients carrying a VUS, clinical documentation was assessed for evidence of provider awareness of the conflict. RESULTS: Fifty of 975 (5.1%) patients with non-negative results carried a variant with a clinically significant conflict, 19 with a pathogenic/likely pathogenic variant reported in APC or MUTYH, and 31 with a VUS reported in CDKN2A, CHEK2, MLH1, MSH2, MUTYH, RAD51C, or TP53. Only 10 of 28 (36%) patients with a VUS with a clinically significant conflict had a documented discussion by a provider about the conflict. Discrepant counseling strategies were used for different patients with the same variant. Among patients with a CDKN2A variant or a monoallelic MUTYH variant, providers were significantly more likely to make recommendations based on the laboratory-reported classification. CONCLUSION: Our findings highlight the frequency of variant interpretation discrepancies and importance of clinician awareness. Guidance is needed on managing patients with discrepant variants to support accurate risk assessment.
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Variación Genética , Neoplasias , Humanos , Neoplasias/genética , Laboratorios , Pruebas Genéticas/métodos , Predisposición Genética a la EnfermedadRESUMEN
To meet the strict requirements of reducing sulfur emissions, an increasing number of commercial ships have installed exhaust gas cleaning systems (EGCSs). However, wash water produced during the cleaning process is discharged back to the marine environment. We investigated the effects of closed-loop scrubber (natrium-alkali method) wash water on three trophic species. Severe toxic effects were found when Dunaliella salina, Mysidopsis bahia, and Mugilogobius chulae were exposed to 0.63-6.25, 0.63-10, and 1.25-20% concentrations of wash water, respectively. The 50% effective concentration in 96 h (EC50-96 h) for D. salina was 2.48%, and the corresponding total polycyclic aromatic hydrocarbons (PAHs) and heavy metals were 22.81 and 23.67 µg L-1. The 50% lethal concentration in 7 d (LC50-7 d) values for M. bahia and M. chulae were 3.57% and 20.50%, respectively. The lowest observed effect concentration (LOEC) values for M. bahia and M. chulae were 1.25% and 2.5%, respectively, and the corresponding total PAHs and heavy metals were 11.50 and 11.93 and 22.99 and 23.86 µg L-1. M. bahia's body weight was negatively correlated with the amount of wash water. Low concentrations of wash water (0-5%) had no significant effect on the reproduction of M. bahia. Although concentrations of 16 PAHs and 8 heavy metals are known, different compounds might react with each other and form more unknown toxic substances, and the measured toxicity comes from synergistic effects between various pollutants. Therefore, future work is needed to clarify other more toxic contaminants in wash water. We highly recommend that wash water be treated before being discharged to the marine environment.
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Metales Pesados , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Navíos , Monitoreo del Ambiente , Emisiones de Vehículos/toxicidad , Metales Pesados/toxicidad , Metales Pesados/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , AguaRESUMEN
DNA nanotechnology provides an approach to create precise, tunable, and biocompatible nanostructures for biomedical applications. However, the stability of these structures is severely compromised in biological milieu due to their fast degradation by nucleases. Recently, we showed how enzymatic polymerization could be harnessed to grow polynucleotide brushes of tunable length and location on the surface of DNA origami nanostructures, which greatly enhances their nuclease stability. Here, we report on strategies that allow for both spatial and temporal control over polymerization through activatable initiation, cleavage, and regeneration of polynucleotide brushes using restriction enzymes. The ability to site-specifically decorate DNA origami nanostructures with polynucleotide brushes in a spatiotemporally controlled way provides access to "smart" functionalized DNA architectures with potential applications in drug delivery and supramolecular assembly.
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Nanoestructuras , Polinucleótidos , Nanoestructuras/química , ADN/química , Nanotecnología , Sistemas de Liberación de Medicamentos , Conformación de Ácido NucleicoRESUMEN
Streptomyces bingchenggensis is the main industrial producer of milbemycins, which are a group of 16-membered macrocylic lactones with excellent insecticidal activities. In the past several decades, scientists have made great efforts to solve its low productivity. However, a lack of understanding of the regulatory network of milbemycin biosynthesis limited the development of high-producing strains using a regulatory rewiring strategy. SARPs (Streptomyces Antibiotic Regulatory Proteins) family regulators are widely distributed and play key roles in regulating antibiotics production in actinobacteria. In this paper, MilR3 (encoded by sbi_06842) has been screened out for significantly affecting milbemycin production from all the 19 putative SARP family regulators in S. bingchenggensis with the DNase-deactivated Cpf1-based integrative CRISPRi system. Interestingly, milR3 is about 7 Mb away from milbemycin biosynthetic gene cluster and adjacent to a putative type II PKS (the core minimal PKS encoding genes are sbi_06843, sbi_06844, sbi_06845 and sbi_06846) gene cluster, which was proved to be responsible for producing a yellow pigment. The quantitative real-time PCR analysis proved that MilR3 positively affected the transcription of specific genes within milbemycin BGC and those from the type II PKS gene cluster. Unlike previous "small" SARP family regulators that played pathway-specific roles, MilR3 was probably a unique SARP family regulator and played a pleotropic role. MilR3 was an upper level regulator in the MilR3-MilR regulatory cascade. This study first illustrated the co-regulatory role of this unique SARP regulator. This greatly enriches our understanding of SARPs and lay a solid foundation for milbemycin yield enhancement in the near future.
Asunto(s)
Regulación Bacteriana de la Expresión Génica , Streptomyces , Antibacterianos/metabolismo , Desoxirribonucleasas/genética , Streptomyces/genética , Streptomyces/metabolismoRESUMEN
PURPOSE: Design an extended osteotomy guide (EOG) for Le Fort I osteotomy to improve the safety of surgery. MATERIALS AND METHODS: The digital Le Fort I osteotomy guide was designed in MIMICS 23.0. Twenty-eight patients were randomized into 2 groups. Patients in the experimental group used EOG, and patients in the control group used a traditional osteotomy guide (TOG). Virtual designs and actual postoperative outcomes were compared by cone-beam computed tomography. The safety of the operation was confirmed by the accuracy of the osteotomy direction and depth on the inner and posterior walls of the maxilla. RESULTS: All positioning deviations of both osteotomy guides were <0.3 mm (P>0.05). The osteotomy depths on the inner and posterior walls with the EOG and TOG deviated by 0.789±1.179 and 1.811±1.345 mm (P=0.004) and 0.648±0.999 and 1.262±0.942 mm (P=0.030), respectively. The angles of deviation of the osteotomy direction on the inner and posterior walls by the EOG and TOG were 2.025±2.434 and 5.069±2.391 degrees (P<0.001) and 2.772±2.979 and 8.653±4.690 degrees (P<0.001), respectively. CONCLUSIONS: The EOG was more accurate than TOG for manipulating osteotomy direction and depth on the inner and posterior maxillary walls. Thus, EOG could ensure higher surgical safety than TOG.
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Maxilar , Osteotomía Maxilar , Cefalometría/métodos , Tomografía Computarizada de Haz Cónico/métodos , Humanos , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Equipo Ortopédico , Osteotomía Le Fort/métodosRESUMEN
Commercialized multigene panel testing brings unprecedented opportunities to understand germline genetic contributions to hereditary cancers. Most genetic testing companies classify the pathogenicity of variants as pathogenic, benign, or variants of unknown significance (VUSs). The unknown pathogenicity of VUSs poses serious challenges to clinical decision-making. This study aims to assess the frequency of VUSs that are likely pathogenic in disease-susceptibility genes. Using estimates of probands' probability of having a pathogenic mutation (ie, the carrier score) based on a family history probabilistic risk prediction model, we assume the carrier score distribution for probands with VUSs is a mixture of the carrier score distribution for probands with positive results and the carrier score distribution for probands with negative results. Under this mixture model, we propose a likelihood-based approach to assess the frequency of pathogenicity among probands with VUSs, while accounting for the existence of possible pathogenic mutations on genes not tested. We conducted simulations to assess the performance of the approach and show that under various settings, the approach performs well with very little bias in the estimated proportion of VUSs that are likely pathogenic. We also estimate the positive predictive value across the entire range of carrier scores. We apply our approach to the USC-Stanford Hereditary Cancer Panel Testing cohort, and estimate the proportion of probands that have VUSs in BRCA1/2 that are likely pathogenic to be 10.12% [95%CI: 0%, 43.04%]. This approach will enable clinicians to target high-risk patients who have VUSs, allowing for early prevention interventions.
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Neoplasias de la Mama , Predisposición Genética a la Enfermedad , Neoplasias de la Mama/genética , Femenino , Pruebas Genéticas , Humanos , Funciones de Verosimilitud , Mutación , VirulenciaRESUMEN
Combining surface-initiated, TdT (terminal deoxynucleotidyl transferase) catalyzed enzymatic polymerization (SI-TcEP) with precisely engineered DNA origami nanostructures (DONs) presents an innovative pathway for the generation of stable, polynucleotide brush-functionalized DNA nanostructures. We demonstrate that SI-TcEP can site-specifically pattern DONs with brushes containing both natural and non-natural nucleotides. The brush functionalization can be precisely controlled in terms of the location of initiation sites on the origami core and the brush height and composition. Coarse-grained simulations predict the conformation of the brush-functionalized DONs that agree well with the experimentally observed morphologies. We find that polynucleotide brush-functionalization increases the nuclease resistance of DONs significantly, and that this stability can be spatially programmed through the site-specific growth of polynucleotide brushes. The ability to site-specifically decorate DONs with brushes of natural and non-natural nucleotides provides access to a large range of functionalized DON architectures that would allow for further supramolecular assembly, and for potential applications in smart nanoscale delivery systems.
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ADN/química , Nanoestructuras/química , Polinucleótidos/química , ADN Nucleotidilexotransferasa/química , Nucleótidos de Desoxiuracil/química , Conformación de Ácido Nucleico , Polimerizacion , Prueba de Estudio Conceptual , Nucleótidos de Timina/químicaRESUMEN
Black phosphorus is well known for its excellent electromechanical properties. Although it has previously been used for therapeutic drug delivery in cancer, it has never been applied as an electroactive polymer for post-trauma tissue regeneration (e.g., in cardiac muscles and neurons). The major concern currently preventing such applications is its controversial biosafety profile in vivo. Here, we demonstrate the production of a concentrically integrative layer-by-layer bioassembled black phosphorus nanoscaffold. This scaffold has remarkable electrical conductivity, permitting smooth release into the surrounding microenvironment. We confirmed that, under mild oxidative stress, our black phosphorus nanoscaffold induced angiogenesis and neurogenesis and stimulated calcium-dependent axon regrowth and remyelination. Long-term in vivo implantation of this nanoscaffold during severe neurological defect regeneration induced negligible toxicity levels. These results provide new insight into the regenerative capability of manufactured 3D scaffolds using neuroengineered 2D black phosphorus nanomaterials.
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Homeostasis/efectos de los fármacos , Nanoestructuras/química , Neovascularización Fisiológica/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Andamios del Tejido/química , Células A549 , Animales , Células HeLa , Humanos , Células PC12 , Ratas , Ratas Sprague-DawleyRESUMEN
Epidemiological studies demonstrate an association between asthma and mental health disorders, although little is known about the shared genetics and causality of this association. Thus, we aimed to investigate shared genetics and the causal link between asthma and mental health disorders.We conducted a large-scale genome-wide cross-trait association study to investigate genetic overlap between asthma from the UK Biobank and eight mental health disorders from the Psychiatric Genomics Consortium: attention deficit hyperactivity disorder (ADHD), anxiety disorder (ANX), autism spectrum disorder, bipolar disorder, eating disorder, major depressive disorder (MDD), post-traumatic stress disorder and schizophrenia (sample size 9537-394â283).In the single-trait genome-wide association analysis, we replicated 130 previously reported loci and discovered 31 novel independent loci that are associated with asthma. We identified that ADHD, ANX and MDD have a strong genetic correlation with asthma at the genome-wide level. Cross-trait meta-analysis identified seven loci jointly associated with asthma and ADHD, one locus with asthma and ANX, and 10 loci with asthma and MDD. Functional analysis revealed that the identified variants regulated gene expression in major tissues belonging to the exocrine/endocrine, digestive, respiratory and haemic/immune systems. Mendelian randomisation analyses suggested that ADHD and MDD (including 6.7% sample overlap with asthma) might increase the risk of asthma.This large-scale genome-wide cross-trait analysis identified shared genetics and potential causal links between asthma and three mental health disorders (ADHD, ANX and MDD). Such shared genetics implicate potential new biological functions that are in common among them.
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Trastornos de Ansiedad/genética , Asma/genética , Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno Depresivo/genética , Adulto , Niño , Estudio de Asociación del Genoma Completo , Humanos , Reino UnidoRESUMEN
This study aimed to develop of a rapid and effective method to occlude dentinal tubules using carboxymethyl chitosan and lysozyme (CMC/LYZ) nanogels with encapsulated amorphous calcium phosphate (ACP) based on the transformation of ACP to HAP. In this work, CMC/LYZ was used to stabilize ACP and form CMC/LYZ-ACP nanogels, and then the nanogel-encapsulated ACP was applied to exposed dentinal tubule surfaces. The morphology of the nanogels was examined by transmission electron microscopy (TEM). Distribution and quantity of elements in CMC/LYZ-ACP nanogels were determined by element mapping and energy dispersive X-Ray spectroscopy (EDX). Scanning electron microscopy (SEM) images, XRD measurements and nanoindentation were applied to check the efficacy of tubular occlusion. TEM revealed that CMC/LYZ-ACP nanogels were spherical dense gel particles with size approximately 50-500 nm. Element mapping and EDX indicated that C, N, O, Ca, P, and S in the microspheres are thoroughly represented. SEM images shows that the thickness of the coating layer was approximately 1-2 µm and the depth to which the mineralized substance enters the dentinal tubule was approximately 4-8 µm. XRD measurements and nanoindentation indicated that the occluding mineralized substance observed were similar to nature dentin. CMC can form spherical dense nanogels loaded with ACP under the participation of lysozyme. The CMC/LYZ-ACP nanogels could increase the dentinal tubule occluding effectiveness. These results indicated that finding and developing novel nanomaterials of CMC/LYZ-ACP would be an effective strategy for the treatment of dentin hypersensitivity.
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Fosfatos de Calcio/química , Quitosano/análogos & derivados , Sensibilidad de la Dentina/terapia , Diente Molar/patología , Muramidasa/química , Nanopartículas/química , Adolescente , Adulto , Quitosano/química , Dentina/química , Ácido Edético/química , Módulo de Elasticidad , Geles , Humanos , Luz , Microscopía Electrónica de Rastreo , Microesferas , Tamaño de la Partícula , Permeabilidad , Reproducibilidad de los Resultados , Dispersión de Radiación , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , Adulto JovenRESUMEN
In Taiwan, remote healthcare initially focused on telemedicine, with systematic development starting in 2007 through the "Remote Care Pilot Program" and subsequent initiatives. Significant advancements came with the "Remote Health Care Services Development Plan" in 2010, which integratedArtificial intelligence and Information and communications technologies, enhancing smart healthcare in home care. This study investigated strategic gaps in smart healthcare applications for remote home care using a mixed-methods approach, particularly the Analytic Hierarchy Process (AHP). This study identified and ranked strategic gaps, including "legal regulations", "economic factors", "user behavior habits", "policy and culture", and "environment and technology". Findings, based on in-depth interviews with 6 experts and 16 AHP questionnaire samples, highlight "legal regulations" and "user behavior habits" as critical areas needing attention. Addressing these gaps can improve user acceptance and the effectiveness of smart healthcare applications, providing valuable insights for future research and practice in making remote home care more comprehensive and efficient.
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Servicios de Atención de Salud a Domicilio , Telemedicina , Taiwán , Humanos , Encuestas y CuestionariosRESUMEN
Steady-state expression quantitative trait loci (eQTLs) explain only a fraction of disease-associated loci identified through genome-wide association studies (GWASs), while eQTLs involved in gene-by-environment (GxE) interactions have rarely been characterized in humans due to experimental challenges. Using a baboon model, we found hundreds of eQTLs that emerge in adipose, liver, and muscle after prolonged exposure to high dietary fat and cholesterol. Diet-responsive eQTLs exhibit genomic localization and genic features that are distinct from steady-state eQTLs. Furthermore, the human orthologs associated with diet-responsive eQTLs are enriched for GWAS genes associated with human metabolic traits, suggesting that context-responsive eQTLs with more complex regulatory effects are likely to explain GWAS hits that do not seem to overlap with standard eQTLs. Our results highlight the complexity of genetic regulatory effects and the potential of eQTLs with disease-relevant GxE interactions in enhancing the understanding of GWAS signals for human complex disease using non-human primate models.
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Dieta Alta en Grasa , Estudio de Asociación del Genoma Completo , Estudio de Asociación del Genoma Completo/métodos , Dieta Alta en Grasa/efectos adversos , Regulación de la Expresión Génica , Sitios de Carácter Cuantitativo/genética , FenotipoRESUMEN
BACKGROUND: At present, not all Type AO/OTA 42A2 open fractures can be treated by external fixation brackets, not to mention the inconvenience of this technique in clinical practice. External titanium alloy locking plates, which are lightweight and easy-to-operate, can be used as an alternative treatment option for such patients. However, there are few reports of finite element biomechanical analysis on the titanium alloy locking plates and fixation brackets being placed on the medial side of the tibial fracture. In this study, the biomechanical properties of titanium alloy locking plates and fixation brackets for treating Type AO/OTA 42A2 fractures were compared by applying the finite element method, and the results provided data support for the clinical application of the external titanium alloy locking plate technique. METHODS: Type AO/OTA 42A2 fracture models were constructed using CT data of a male volunteer for two external fixation techniques, namely the external titanium alloy locking plate technique and the external fixation bracket technique, according to commonly-used clinical protocols. Then, the four-point bending, axial compression, clockwise rotation and counterclockwise rotation tests under the maximum load were simulated in finite element analysis software. The stress distribution, peak stress and overall tibial displacement data for the two different external fixation techniques were obtained and compared. RESULTS: In the four different test conditions (i.e., four-point bending, axial compression, clockwise torsion, counterclockwise torsion) under the maximum load, the two external fixation techniques showed obvious von Mises stress concentration at the contacts between the screw and tibia, between the screw and titanium alloy locking plate, between the self-tapping self-drilling needle and tibia, between the self-tapping self-drilling needle and the external fixation device, as well as around the fracture end and around the cortical bone at the upper and lower ends of the tibia. The peak stress was ranged 26.67-558.77 MPa, all below the yield stress strength of titanium alloy. The peak tibial displacement of the external titanium alloy locking plate model was smaller than that of the fixation bracket model. In terms of structural stability, the external titanium alloy locking plate technique was superior to the external fixation bracket technique. CONCLUSIONS: When fixing Type AO/OTA 42A2 fractures, external titanium alloy locking plates are not only lightweight and easy-to-operate, but also have better performance in terms of axial compression, bending and torsion resistance. According to the finite element biomechanical analysis, external titanium alloy locking plates are superior to traditional external fixation brackets in treating Type AO/OTA 42A2 fractures and can better meet the needs of clinical application.
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Fijación Interna de Fracturas , Fracturas de la Tibia , Humanos , Masculino , Análisis de Elementos Finitos , Fijación Interna de Fracturas/métodos , Titanio , Fijadores Externos , Fenómenos Biomecánicos , Fijación de Fractura , Placas Óseas , Fracturas de la Tibia/diagnóstico por imagen , Fracturas de la Tibia/cirugíaRESUMEN
Steady-state expression quantitative trait loci (eQTLs) explain only a fraction of disease-associated loci identified through genome-wide association studies (GWAS), while eQTLs involved in gene-by-environment (GxE) interactions have rarely been characterized in humans due to experimental challenges. Using a baboon model, we found hundreds of eQTLs that emerge in adipose, liver, and muscle after prolonged exposure to high dietary fat and cholesterol. Diet-responsive eQTLs exhibit genomic localization and genic features that are distinct from steady-state eQTLs. Furthermore, the human orthologs associated with diet-responsive eQTLs are enriched for GWAS genes associated with human metabolic traits, suggesting that context-responsive eQTLs with more complex regulatory effects are likely to explain GWAS hits that do not seem to overlap with standard eQTLs. Our results highlight the complexity of genetic regulatory effects and the potential of eQTLs with disease-relevant GxE interactions in enhancing the understanding of GWAS signals for human complex disease using nonhuman primate models.
RESUMEN
OBJECTIVE: To evaluate whether the pedicle submental island flap (SIF) can be safely used in the oral tongue squamous cell carcinoma (OTSCC) patients with pathologically node-positive (pN+) neck, especially pN+ at level I. METHODS: Retrospectively, 101 OTSCC patients with SIF reconstruction were enrolled. Oncological outcomes included the total locoregional recurrence, the SIF related locoregional recurrence (SRLR) which referred to the local recurrence at flap and ipsilateral neck recurrence at level I, recurrence free survival (RFS), overall survival (OS), and disease specific survival (DSS). RESULTS: Sixty-one patients were pathologically node-negative (pN0) and 40 were pN+. Thirteen patients experienced locoregional recurrence, of which 5 had a SRLR. The pN+ group had a significantly higher locoregional recurrence rate, lower 5-year RFS, OS and DSS than pN0 group (P < 0.05). Patients with pN0 had a significantly higher neck RFS when compared to those with pN+ either at level I (P = 0.005) or at other levels (P < 0.001). However, the neck RFS was similar between the two subgroups of pN+ (P = 0.550). Especially, patients with pN+ at level I had a significantly higher SRLR rate (P = 0.006) compared to those with pN0 at level I. Multivariate analysis showed that pN+ was an unfavorable factor for tumor recurrence and OS. CONCLUSION: Our data did not support the use of SIF in OTSCC patients with pN+ neck at level I due to an significantly increased SRLR rate compared to those with pN0 neck at level I.
Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Procedimientos de Cirugía Plástica , Neoplasias de la Lengua , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/cirugía , Estudios Retrospectivos , Carcinoma de Células Escamosas/cirugía , Carcinoma de Células Escamosas/patología , Neoplasias de la Lengua/cirugía , Neoplasias de la Lengua/patología , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/patología , Colgajos Quirúrgicos/cirugía , Neoplasias de Cabeza y Cuello/cirugíaRESUMEN
Background: N-linoleyltyrosine (NITyr), one of the anandamide analogs, exerts activity via the endocannabinoid receptors (CB1 and CB2), which showed anti-tumor effects in various tumors. Therefore, we speculated that NITyr might show anti-non-small cell lung cancer (NSCLC) effects via the CB1 or CB2 receptor. The purpose of the investigation was to reveal the anti-tumor ability of NITyr on A549 cells and its mechanisms. Methods: The viability of A549 cells was measured by MTT assay, and the cell cycle and apoptosis were both examined by flow cytometry; in addition, cell migration was tested by wound healing assay. Apoptosis-related markers were measured by immunofluorescence. The downstream signaling pathways (PI3K, ERK, and JNK) of CB1 or CB2 were examined through Western blotting. The expressions of CB1 and CB2 were detected by immunofluorescence. Finally, the AutoDock software was used to validate the binding affinity between the targets, such as CB1 and CB2, with NITyr. Results: We found that NITyr inhibited cell viability, hindered the cell cycle, resulted in apoptosis, and inhibited migration. The CB1 inhibitor, AM251, and the CB2 inhibitor, AM630, weakened the aforementioned phenomenon. The immunofluorescence assay suggested that NITyr upregulated the expression of CB1 and CB2. Western blot analysis indicated that NITyr upregulated the expression of p-ERK, downregulated the expression of p-PI3K, and did not affect p-JNK expression. In conclusion, NITyr showed a role in inhibiting NSCLC through the activation of CB1 and CB2 receptors involved in PI3K and ERK pathways.