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1.
Genes Dev ; 34(17-18): 1177-1189, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32792353

RESUMEN

Dysregulation of the ubiquitin-proteasomal system (UPS) enables pathogenic accumulation of disease-driving proteins in neurons across a host of neurological disorders. However, whether and how the UPS contributes to oligodendrocyte dysfunction and repair after white matter injury (WMI) remains undefined. Here we show that the E3 ligase VHL interacts with Daam2 and their mutual antagonism regulates oligodendrocyte differentiation during development. Using proteomic analysis of the Daam2-VHL complex coupled with conditional genetic knockout mouse models, we further discovered that the E3 ubiquitin ligase Nedd4 is required for developmental myelination through stabilization of VHL via K63-linked ubiquitination. Furthermore, studies in mouse demyelination models and white matter lesions from patients with multiple sclerosis corroborate the function of this pathway during remyelination after WMI. Overall, these studies provide evidence that a signaling axis involving key UPS components contributes to oligodendrocyte development and repair and reveal a new role for Nedd4 in glial biology.


Asunto(s)
Diferenciación Celular , Proteínas de Microfilamentos/metabolismo , Ubiquitina-Proteína Ligasas Nedd4/metabolismo , Regeneración Nerviosa/genética , Enfermedades del Sistema Nervioso/genética , Oligodendroglía/fisiología , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Proteínas de Unión al GTP rho/metabolismo , Animales , Regulación del Desarrollo de la Expresión Génica , Humanos , Ratones , Ratones Noqueados , Esclerosis Múltiple/fisiopatología , Vaina de Mielina/genética , Enfermedades del Sistema Nervioso/fisiopatología , Oligodendroglía/citología , Estabilidad Proteica , Ubiquitinación/genética
2.
Cell ; 149(7): 1565-77, 2012 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-22726442

RESUMEN

Secreted Wnt morphogens are signaling molecules essential for embryogenesis, pathogenesis, and regeneration and require distinct modifications for secretion, gradient formation, and activity. Whether Wnt proteins can be posttranslationally inactivated during development and homeostasis is unknown. Here we identify, through functional cDNA screening, a transmembrane protein Tiki1 that is expressed specifically in the dorsal Spemann-Mangold Organizer and is required for anterior development during Xenopus embryogenesis. Tiki1 antagonizes Wnt function in embryos and human cells via a TIKI homology domain that is conserved from bacteria to mammals and acts likely as a protease to cleave eight amino-terminal residues of a Wnt protein, resulting in oxidized Wnt oligomers that exhibit normal secretion but minimized receptor-binding capability. Our findings identify a Wnt-specific protease that controls head formation, reveal a mechanism for morphogen inactivation through proteolysis-induced oxidation-oligomerization, and suggest a role of the Wnt amino terminus in evasion of oxidizing inactivation. TIKI proteins may represent potential therapeutic targets.


Asunto(s)
Tipificación del Cuerpo , Cabeza/embriología , Proteínas de la Membrana/metabolismo , Metaloproteasas/metabolismo , Vía de Señalización Wnt , Proteínas de Xenopus/metabolismo , Xenopus/embriología , Secuencia de Aminoácidos , Animales , Embrión no Mamífero/metabolismo , Regulación del Desarrollo de la Expresión Génica , Células HEK293 , Células HeLa , Humanos , Proteínas de la Membrana/genética , Metaloproteasas/genética , Datos de Secuencia Molecular , Organizadores Embrionarios/metabolismo , Alineación de Secuencia , Xenopus/metabolismo , Proteínas de Xenopus/genética
3.
Proc Natl Acad Sci U S A ; 120(35): e2304112120, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37607236

RESUMEN

Wnt signaling plays an essential role in developmental and regenerative myelination in the central nervous system. The Wnt signaling pathway is composed of multiple regulatory layers; thus, how these processes are coordinated to orchestrate oligodendrocyte (OL) development remains unclear. Here, we show CK2α, a Wnt/ß-catenin signaling Ser/Thr kinase, phosphorylates Daam2, inhibiting its function and Wnt activity during OL development. Intriguingly, we found Daam2 phosphorylation differentially impacts distinct stages of OL development, accelerating early differentiation followed by decelerating maturation and myelination. Application toward white matter injury revealed CK2α-mediated Daam2 phosphorylation plays a protective role for developmental and behavioral recovery after neonatal hypoxia, while promoting myelin repair following adult demyelination. Together, our findings identify a unique regulatory node in the Wnt pathway that regulates OL development via protein phosphorylation-induced signaling complex instability and highlights a new biological mechanism for myelin restoration.


Asunto(s)
Sustancia Blanca , Fosforilación , Vaina de Mielina , Vía de Señalización Wnt
4.
Bioinformatics ; 39(11)2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37971954

RESUMEN

MOTIVATION: In the medical field, multiple terminology bases coexist across different institutions and contexts, often resulting in the presence of redundant terms. The identification of overlapping terms among these bases holds significant potential for harmonizing multiple standards and establishing unified framework, which enhances user access to comprehensive and well-structured medical information. However, the majority of terminology bases exhibit differences not only in semantic aspects but also in the hierarchy of their classification systems. The conventional approaches that rely on neighborhood-based methods such as GCN may introduce errors due to the presence of different superordinate and subordinate terms. Therefore, it is imperative to explore novel methods to tackle this structural challenge. RESULTS: To address this heterogeneity issue, this paper proposes a multi-view alignment approach that incorporates the hierarchical structure of terminologies. We utilize BERT-based model to capture the recursive relationships among different levels of hierarchy and consider the interaction information of name, neighbors, and hierarchy between different terminologies. We test our method on mapping files of three medical open terminologies, and the experimental results demonstrate that our method outperforms baseline methods in terms of Hits@1 and Hits@10 metrics by 2%. AVAILABILITY AND IMPLEMENTATION: The source code will be available at https://github.com/Ulricab/Bert-Path upon publication.


Asunto(s)
Programas Informáticos , Vocabulario Controlado , Semántica , Benchmarking , Estándares de Referencia
5.
Phys Rev Lett ; 132(8): 086101, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38457702

RESUMEN

The exploration of solid-solid phase transition suffers from the uncertainty of how atoms in two crystal structures match. We devised a theoretical framework to describe and classify crystal-structure matches (CSM). Such description fully exploits the translational and rotational symmetries and is independent of the choice of supercells. This is enabled by the use of the Hermite normal form, an analog of reduced echelon form for integer matrices. With its help, exhausting all CSMs is made possible, which goes beyond the conventional optimization schemes. In an example study of the martensitic transformation of steel, our enumeration algorithm finds many candidate CSMs with lower strains than known mechanisms. Two long-sought CSMs accounting for the most commonly observed Kurdjumov-Sachs orientation relationship and the Nishiyama-Wassermann orientation relationship are unveiled. Given the comprehensiveness and efficiency, our enumeration scheme provide a promising strategy for solid-solid phase transition mechanism research.

6.
Ecotoxicol Environ Saf ; 271: 115963, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38232526

RESUMEN

As a fungicide with the characteristics of high effectiveness, internal absorption and broad spectrum, imazalil is widely used to prevent and treat in fruits and vegetables. Here, pregnant C57BL/6 mice were exposed to imazalil at dietary levels of 0, 0.025‰, and 0.25‰ through drinking water during pregnancy and lactation. We then analyzed the phenotype, metabolome, and expression of related genes and proteins in the livers of mice. There was a marked decrease in the body and liver weights of male offspring mice after maternal imazalil exposure, while this effect on the dam and female offspring was slight. Metabolomics analyses revealed that imazalil significantly altered the metabolite composition of liver samples from both dams and offspring. The preliminary results of the analysis indicated that glucolipid metabolism was the pathway most significantly affected by imazalil. We performed a coabundance association analysis of metabolites with significant changes in the pathway of glycolipid metabolism, and IMZ altered the networks of both dams and offspring compared with the network in control mice, especially in male offspring. The hepatic triglyceride, non-esterified fatty acid and glucose levels were increased significantly in the dams but decreased significantly in male offspring after maternal imazalil exposure. Furthermore, the expression levels of genes associated with glycolipid metabolism and m6A RNA methylation were significantly affected by maternal intake of imazalil. Imazalil-induced glucolipid metabolism disturbance was highly correlated with m6A RNA methylation. In conclusion, maternal imazalil exposure resulted in glucolipid metabolism disturbance and abnormal m6A RNA methylation in the livers of dams and offspring mice. We expected that the information acquired in this study will provide novel evidence for understanding the effect of maternal imazalil exposure on potential health risks.


Asunto(s)
Imidazoles , Hígado , Metilación de ARN , Embarazo , Ratones , Masculino , Femenino , Animales , Ratones Endogámicos C57BL , Hígado/metabolismo , Glucolípidos/metabolismo
7.
J Cell Sci ; 134(2)2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33310913

RESUMEN

Wnt signaling plays a critical role in development across species and is dysregulated in a host of human diseases. A key step in signal transduction is the formation of Wnt receptor signalosomes, during which a large number of components translocate to the membrane, cluster together and amplify downstream signaling. However, the molecular processes that coordinate these events remain poorly defined. Here, we show that Daam2 regulates canonical Wnt signaling via the PIP2-PIP5K axis through its association with Rac1. Clustering of Daam2-mediated Wnt receptor complexes requires both Rac1 and PIP5K, and PIP5K promotes membrane localization of these complexes in a Rac1-dependent manner. Importantly, the localization of Daam2 complexes and Daam2-mediated canonical Wnt signaling is dependent upon actin polymerization. These studies - in chick spinal cord and human and monkey cell lines - highlight novel roles for Rac1 and the actin cytoskeleton in the regulation of canonical Wnt signaling and define Daam2 as a key scaffolding hub that coordinates membrane translocation and signalosome clustering.


Asunto(s)
Proteínas Portadoras , Vía de Señalización Wnt , Animales , Línea Celular , Pollos , Análisis por Conglomerados , Haplorrinos , Humanos , Ratones , Proteínas de Microfilamentos , Fosforilación , Médula Espinal/metabolismo , Proteína de Unión al GTP rac1/genética , Proteína de Unión al GTP rac1/metabolismo , Proteínas de Unión al GTP rho
8.
Phys Rev Lett ; 130(7): 070601, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36867808

RESUMEN

A quantum instruction set is where quantum hardware and software meet. We develop characterization and compilation techniques for non-Clifford gates to accurately evaluate its designs. Applying these techniques to our fluxonium processor, we show that replacing the iSWAP gate by its square root SQiSW leads to a significant performance boost at almost no cost. More precisely, on SQiSW we measure a gate fidelity of up to 99.72% and averaging at 99.31%, and realize Haar random two-qubit gates with an average fidelity of 96.38%. This is an average error reduction of 41% for the former and a 50% reduction for the latter compared to using iSWAP on the same processor.

9.
Neural Comput ; 35(9): 1543-1565, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37437205

RESUMEN

In this letter, we use composite optimization algorithms to solve sigmoid networks. We equivalently transfer the sigmoid networks to a convex composite optimization and propose the composite optimization algorithms based on the linearized proximal algorithms and the alternating direction method of multipliers. Under the assumptions of the weak sharp minima and the regularity condition, the algorithm is guaranteed to converge to a globally optimal solution of the objective function even in the case of nonconvex and nonsmooth problems. Furthermore, the convergence results can be directly related to the amount of training data and provide a general guide for setting the size of sigmoid networks. Numerical experiments on Franke's function fitting and handwritten digit recognition show that the proposed algorithms perform satisfactorily and robustly.

10.
EMBO Rep ; 22(12): e53200, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-34633730

RESUMEN

Astrocytes display extraordinary morphological complexity that is essential to support brain circuit development and function. Formin proteins are key regulators of the cytoskeleton; however, their role in astrocyte morphogenesis across diverse brain regions and neural circuits is unknown. Here, we show that loss of the formin protein Daam2 in astrocytes increases morphological complexity in the cortex and olfactory bulb, but elicits opposing effects on astrocytic calcium dynamics. These differential physiological effects result in increased excitatory synaptic activity in the cortex and increased inhibitory synaptic activity in the olfactory bulb, leading to altered olfactory behaviors. Proteomic profiling and immunoprecipitation experiments identify Slc4a4 as a binding partner of Daam2 in the cortex, and combined deletion of Daam2 and Slc4a4 restores the morphological alterations seen in Daam2 mutants. Our results reveal new mechanisms regulating astrocyte morphology and show that congruent changes in astrocyte morphology can differentially influence circuit function.


Asunto(s)
Astrocitos , Proteínas de Microfilamentos/genética , Proteínas de Unión al GTP rho/genética , Forminas , Morfogénesis , Bulbo Olfatorio/metabolismo , Proteómica , Simportadores de Sodio-Bicarbonato
11.
Nutr Neurosci ; 26(5): 445-455, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35385370

RESUMEN

Brain aging is a complex biological process often associated with a decline in cognitive functions and motility. Astaxanthin (AST) is a strong antioxidant capable of crossing the blood-brain barrier. The effect of AST on brain aging and its physiological and molecular mechanism are still unclear. The study aimed to investigate whether AST from AstaReal A1010 improved brain aging by inducing autophagy in SAMP10 mice. Different concentrations of AstaReal A1010 were intragastrically administered to 6-month-old SAMP10 mice for 3 months. The results demonstrated that AST delayed age-related cognitive decline, motor ability and neurodegeneration, upregulated the expression levels of autophagy-related genes beclin-1 and LC3 in the brain. It may induce autophagy by regulating IGF-1/Akt/mTOR and IGF-1/Akt/FoxO3a signaling. Treatment with autophagy inhibitor 3-methyladenine (3MA) partly reversed the anti-aging effect of AST. In conclusion, our findings suggest that AST may induce autophagy by regulating IGF-1/Akt/mTOR and IGF-1/Akt/FoxO3a signaling, thereby delaying age-related neurodegeneration and cognitive decline in SAMP10 mice.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina , Proteínas Proto-Oncogénicas c-akt , Ratones , Animales , Factor I del Crecimiento Similar a la Insulina/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Envejecimiento/fisiología , Encéfalo/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/farmacología , Autofagia
12.
BMC Med Inform Decis Mak ; 23(1): 34, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788504

RESUMEN

In recent years, relation extraction on unstructured texts has become an important task in medical research. However, relation extraction requires a large amount of labeled corpus, manually annotating sequences is time consuming and expensive. Therefore, efficient and economical methods for annotating sequences are required to ensure the performance of relational extraction. This paper proposes a method of subsequence and distant supervision based active learning. The method is annotated by selecting information-rich subsequences as a sampling unit instead of the full sentences in traditional active learning. Additionally, the method saves the labeled subsequence texts and their corresponding labels in a dictionary which is continuously updated and maintained, and pre-labels the unlabeled set through text matching based on the idea of distant supervision. Finally, the method combines a Chinese-RoBERTa-CRF model for relation extraction in Chinese medical texts. Experimental results test on the CMeIE dataset achieves the best performance compared to existing methods. And the best F1 value obtained between different sampling strategies is 55.96%.


Asunto(s)
Aprendizaje Basado en Problemas , Aprendizaje Automático Supervisado , Lenguaje , China , Obras Médicas de Referencia
13.
Int J Mol Sci ; 24(17)2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37686435

RESUMEN

Vanillin holds significant importance as a flavoring agent in various industries, including food, pharmaceuticals, and cosmetics. The CoA-dependent pathway for the biosynthesis of vanillin from ferulic acid involved feruloyl-CoA synthase (Fcs) and enoyl-CoA hydratase/lyase (Ech). In this research, the Fcs and Ech were derived from Streptomyces sp. strain V-1. The sequence conservation and structural features of Ech were analyzed by computational techniques including sequence alignment and molecular dynamics simulation. After detailed study for the major binding modes and key amino acid residues between Ech and substrates, a series of mutations (F74W, A130G, A130G/T132S, R147Q, Q255R, ΔT90, ΔTGPEIL, ΔN1-11, ΔC260-287) were obtained by rational design. Finally, the yield of vanillin produced by these mutants was verified by whole-cell catalysis. The results indicated that three mutants, F74W, Q147R, and ΔN1-11, showed higher yields than wild-type Ech. Molecular dynamics simulations and residue energy decomposition identified the basic residues K37, R38, K561, and R564 as the key residues affecting the free energy of binding between Ech and feruloyl-coenzyme A (FCA). The large changes in electrostatic interacting and polar solvating energies caused by the mutations may lead to decreased enzyme activity. This study provides important theoretical guidance as well as experimental data for the biosynthetic pathway of vanillin.


Asunto(s)
Liasas , Enoil-CoA Hidratasa/genética , Benzaldehídos , Aminoácidos
14.
Bioinformatics ; 37(20): 3610-3617, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34037691

RESUMEN

MOTIVATION: Medical terminology normalization aims to map the clinical mention to terminologies coming from a knowledge base, which plays an important role in analyzing electronic health record and many downstream tasks. In this article, we focus on Chinese procedure terminology normalization. The expressions of terminology are various and one medical mention may be linked to multiple terminologies. Existing studies based on learning to rank does not fully consider the quality of negative samples during model training and the importance of keywords in this domain-specific task. RESULTS: We propose a combined recall and rank framework to solve these problems. A pair-wise Bert model with deep metric learning is used to recall candidates. Previous methods either train Bert in a point-wise way or based on a multi-class classification problem, which may lead serious efficiency problems or not be effective enough. During model training, we design a novel online negative sampling algorithm to activate the pair-wise method. To deal with multi-implication scenarios, we train the task of implication number prediction together with the recall task in a multi-task learning setting, since these two tasks are highly complementary. In rank step, we propose a keywords attentive mechanism to focus on domain-specific information such as procedure sites and procedure types. Finally, a fusion block merges the results of the recall and the rank model. Detailed experimental analysis shows our proposed framework has a remarkable improvement on both performance and efficiency. AVAILABILITY AND IMPLEMENTATION: The source code will be available at https://github.com/sxthunder/CMTN upon publication.

15.
Ann Clin Microbiol Antimicrob ; 21(1): 12, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35303873

RESUMEN

BACKGROUND: Legionellosis remains a public health problem. The most common diagnostic method to detect Legionella pneumophila (L. pneumophila) is culture. Polymerase chain reaction (PCR) is a fast and accurate method for this detection in environmental samples. METHODS: Four databases were searched for studies that evaluated the detection efficiency of PCR in L. pneumophila. The quality evaluation was conducted using Review Manager 5.3. We used Meta-DiSc 1.4 software and the Stata 15.0 software to create forest plots, a meta-regression, a bivariate boxplot and a Deeks' funnel plot. RESULTS: A total of 18 four-fold tables from 16 studies were analysed. The overall pooled sensitivity and specificity of PCR was 94% and 72%, respectively. The positive likelihood ratio (RLR) and negative likelihood ratio (NLR) was 2.73 and 0.12, respectively. The result of the diagnostic odds ratio (DOR) was 22.85 and the area under the curve (AUC) was 0.7884. CONCLUSION: Establishing a laboratory diagnostic tool for L. pneumophila detection is important for epidemiological studies. In this work, PCR demonstrated a promising diagnostic accuracy for L. pneumophila.


Asunto(s)
Legionella pneumophila , Bases de Datos Bibliográficas , Microbiología Ambiental , Humanos , Legionella pneumophila/genética , Legionella pneumophila/aislamiento & purificación , Oportunidad Relativa , Reacción en Cadena de la Polimerasa/métodos , Sensibilidad y Especificidad
16.
J Clin Lab Anal ; 36(2): e24238, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35034374

RESUMEN

OBJECTIVES: Even today, tuberculosis (TB) remains a leading public health problem; yet, the current diagnostic methods still have a few shortcomings. Lipoarabinomannan (LAM) provides an opportunity for TB diagnosis, and urine LAM detection seems to have a promising and widely applicable prospect. DESIGN OR METHODS: Four databases were systematically searched for eligible studies, and the quality of the studies was evaluated using the quality assessment of diagnostic accuracy studies-2 (QUADAS-2). Graphs and tables were created to show sensitivity, specificity, likelihood ratios, diagnostic odds ratio (DOR), the area under the curve (AUC), and so on. RESULTS: Based on the included 67 studies, the pooled sensitivity of urine LAM was 48% and specificity was 89%. In the subgroup analyses, the FujiLAM test had higher sensitivity (69%) and specificity (92%). Furthermore, among patients infected with human immunodeficiency virus (HIV), 50% of TB patients were diagnosed using a urine LAM test. Besides, the CD4+ cell count was inversely proportional to the sensitivity. CONCLUSIONS: Urine LAM is a promising diagnostic test for TB, particularly using the FujiLAM in HIV-infected adults whose CD4+ cell count is ≤100 per µl. Besides, the urine LAM test shows various sensitivities and specificities in different subgroups in terms of age, HIV infection status, CD4+ cell count, and testing method.


Asunto(s)
Lipopolisacáridos/orina , Tuberculosis/diagnóstico , Adulto , Recuento de Linfocito CD4 , Niño , Infecciones por VIH/complicaciones , Humanos , Mycobacterium tuberculosis , Sensibilidad y Especificidad , Tuberculosis/complicaciones , Tuberculosis/orina
17.
Hepatobiliary Pancreat Dis Int ; 21(2): 106-112, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34583911

RESUMEN

Mammalian target of rapamycin (mTOR) inhibitor as an attractive drug target with promising antitumor effects has been widely investigated. High quality clinical trial has been conducted in liver transplant (LT) recipients in Western countries. However, the pertinent studies in Eastern world are paucity. Therefore, we designed a clinical trial to test whether sirolimus can improve recurrence-free survival (RFS) in hepatocellular carcinoma (HCC) patients beyond the Milan criteria after LT. This is an open-labeled, single-arm, prospective, multicenter, and real-world study aiming to evaluate the clinical outcomes of early switch to sirolimus-based regimens in HCC patients after LT. Patients with a histologically proven HCC and beyond the Milan criteria will be enrolled. The initial immunosuppressant regimens are center-specific for the first 4-6 weeks. The following regimens integrated sirolimus into the regimens as a combination therapy with reduced calcineurin inhibitors based on the condition of patients and centers. The study is planned for 4 years in total with a 2-year enrollment period and a 2-year follow-up. We predict that sirolimus conversion regimen will provide survival benefits for patients particular in the key indicator RFS as well as better quality of life. If the trial is conducted successfully, we will have a continued monitoring over a longer follow-up time to estimate indicator of overall survival. We hope that the outcome will provide better evidence for clinical decision-making and revising treatment guidelines based on Chinese population data. Trial register: Trial registered at http://www.chictr.org.cn: ChiCTR2100042869.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Trasplante de Hígado , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/cirugía , Humanos , Inmunosupresores/efectos adversos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/cirugía , Trasplante de Hígado/métodos , Estudios Multicéntricos como Asunto , Recurrencia Local de Neoplasia/tratamiento farmacológico , Estudios Prospectivos , Calidad de Vida , Sirolimus/efectos adversos , Resultado del Tratamiento
18.
J Prosthet Dent ; 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35963711

RESUMEN

STATEMENT OF PROBLEM: Whether early loaded implants have similar clinical outcomes to delayed loaded implants is unclear. PURPOSE: The purpose of this systematic review and meta-analysis was to compare the outcomes of early and delayed loading dental implants. MATERIAL AND METHODS: Comprehensive searches of the MEDLINE, EMBASE, and Ovid databases were enriched by hand searches. Only human randomized controlled trials (RCTs) that compared the clinical efficacy of early and delayed loading were included. The survival rates and marginal bone level (MBL) changes were pooled and analyzed by risk ratios (RRs) and weighted mean differences (WMDs), respectively. The subgroup analyses, which were based on the Mantel-Haenszel and inverse-variance methods, included the types of prosthesis, implant time, occlusion, number of missing teeth, operation methods, dental position, healing methods, and type of first restoration. A funnel plot was used for heterogeneity analysis. RESULTS: Eighteen trials were included from the initial 601 articles. The dental implant survival rates for the early and delayed loading were similar (P>.05). Regarding the marginal bone level changes, the 2 loading protocols also reached a comparable clinical outcome (P>.05). CONCLUSIONS: Early implant loading should achieve the same clinical efficacy as the delayed loading method.

19.
Microb Pathog ; 160: 105191, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34571151

RESUMEN

BACKGROUND: Recent studies have revealed that gut microbiota play an important part in the regulation of the immune function. With the development of newer detection methods, our cognition of the human gut microbiota continues to evolve with startling speed, but our understanding of the changes in the structure and function of gut microbiota before and after renal transplantation and the practical applications of this knowledge are still in their infancy. METHODS: We prospectively recruited 10 renal transplant recipients and collected serial fecal specimens (N = 30) before the operation, and on the 7th and 30th day after the operation, and characterized their gut microbiota structure through deep sequencing of the 16S rRNA V4-V5 variable region and analyzed the presence of metabolites using LC-MS methods. RESULTS: A decrease in the relative abundance of overall gut microbiota was detected in post-transplantation samples compared to that in pre-transplantation samples. Principal coordinate analysis (PCoA) inhibited a obvious separation between the three groups, and the linear discriminant analysis effect size (LEfSe) method showed that Clostridiales, Clostridia, Ruminococcaceae, Faecalibacterium, and Veillonellaceae were all significantly more abundant in the fecal specimens from the pre-transplantation group while Bacilli, Enterococcaceae, and Enterococcus were significantly more abundant in the fecal specimens from the four weeks post-transplantation group. Anaerostipes and Clostridia-bacterium were detected in the fecal samples from the one week post-transplantation group. Analysis of community composition did not reveal any significant difference between the pre-transplantation group and the post-transplantation group. The metabolic profiling of the volunteers before renal transplantation were distinct from the post-transplantation profiling, which gather together in PCA (Fig. 4A). After renal transplantation, the metabolic profiling of post-transplantation specimens revealed marked diversity and complexity. CONCLUSIONS: Our research indicated remarkable variations in the gut microbiota and metabolites following renal transplantation, and that the gut microbiota and metabolites of patients with uremia were relatively stable and showed reasonable concordance. Distinct microbial compositions and metabolites were observed in patients after transplantation.


Asunto(s)
Microbioma Gastrointestinal , Trasplante de Riñón , Heces , Humanos , ARN Ribosómico 16S/genética , Receptores de Trasplantes
20.
Phys Rev Lett ; 126(18): 185501, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34018788

RESUMEN

Starting from Shannon's definition of dynamic entropy, we propose a theory to describe the rare-event-determined dynamic states in condensed matter and their transitions and apply it to high-pressure ice VII. A dynamic intensive quantity named dynamic field, rather than the conventional thermodynamic intensive quantities such as temperature and pressure, is taken as the controlling variable. The dynamic entropy versus dynamic field curve demonstrates two dynamic states in the stability region of ice VII and dynamic ice VII. Their microscopic differences were assigned to the dynamic patterns of proton transfer. This study puts a similar dynamical theory used in earlier studies of glass models on a simpler and more fundamental basis, which could be applied to describe the dynamic states of more realistic condensed matter systems.

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