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1.
Chem Biodivers ; : e202400670, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747034

RESUMEN

Cancer remains a significant global health concern, with mortality rates steadily rising and prompting an urgent search for effective treatments. This study focuses on the medicinal properties of plants from the Phyllanthus genus, specifically Phyllanthus amarus and Phyllanthus niruri, which have shown promise in traditional medicine. Through bioguided fractionation using preparative high-performance liquid chromatography (HPLC), bioactive compounds were isolated and identified using ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry (UHPLC-QTOF-MSE) and nuclear magnetic resonance (NMR) spectroscopy. Chemometric analyses such as principal component analysis (PCA) aided in understanding metabolite distribution. Biological assays demonstrated cytotoxic activities of specific fractions against cancer cell lines, notably the PhyN 4n fraction from P. niruri, which induced S-phase cell cycle arrest and apoptosis in HL60 cells. These findings underscore the anticancer potential of Phyllanthus species and lay the groundwork for future drug development efforts. The study's integration of advanced analytical techniques, chemometrics, and biological assays provides valuable insights for harnessing natural products in the fight against cancer.

2.
Clin Oral Investig ; 27(5): 1801-1814, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36757462

RESUMEN

OBJECTIVE: To assess the accuracy of cone-beam computed tomography (CBCT) for determining gingival thickness. MATERIAL AND METHODS: Searches were undertaken in PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, LIVIVO, and gray literature (Google Scholar and ProQuest) for studies considered eligible according to the following criteria: cross-sectional observational studies, which compared CBCT accuracy with that of transgingival probing when determining gingival thickness, in adult patients with good periodontal health. No language or time restrictions were applied in this systematic review. The risk of bias was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for analytical cross-sectional studies. RESULTS: Six articles were included for qualitative synthesis, involving a pooled sample of 132 patients with a mean age of 29 years (18-51 years). Of these 6 studies, 5 were eligible for quantitative analysis. The meta-analysis showed no statistically significant difference between CBCT and transgingival probing measures of gingival tissue (mean difference of 0.10 (95% CI-0.17-0.38). No significant level of heterogeneity was detected (Tau2-P = 0.0662; I2 = 0%; H2-P = 1.000; Q-P = 1.134). According to the GRADE criterion, confidence in the cumulative evidence was considered low. CONCLUSIONS: CBCT is an accurate method for determining gingival tissue thickness, comparable to the reference standard (transgingival probing). CLINICAL RELEVANCE: CBCT could be considered for gingival thickness measurement when bone thickness is also needed, and thereby aid in the assessment of gingival biotype without the discomfort and anesthesia needed in transgingival probing. TRIAL REGISTRATION: This protocol was registered at the PROSPERO database (International Prospective Register of Systematic Review) under registration number CRD42022326970. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022326970 .


Asunto(s)
Tomografía Computarizada de Haz Cónico , Encía , Adulto , Humanos , Estudios Transversales , Encía/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Examen Físico
3.
Clin Oral Investig ; 27(2): 433-474, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36700991

RESUMEN

OBJECTIVES: To evaluate the influence of image acquisition parameters (voxel, FOV, kVp, mA) on the accuracy of cone-beam computed tomography (CBCT) in detecting vertical root fracture (VRF). MATERIAL AND METHODS: Searches were performed in 6 main databases and the gray literature, without restrictions of language or date. Observational clinical studies (OCS) and in vitro-extracted teeth (IV) studies were considered eligible for inclusion when investigating the accuracy (sensitivity, specificity) of CBCT in detecting VRF in human teeth. The risk of bias was assessed using QUADAS-2, and a meta-analysis was performed using Review Manager v5.4 software and Jamovi software v1.6. RESULTS: A total of 60 out of 132 articles was included after fulfilling the eligibility criteria. Of these, 54 were IV studies while 6 were OCS. In the IV studies, it was seen that smaller FOV sizes tended to present higher accuracy values. The meta-analysis of the 6 OCS showed that the overall sensitivity and specificity values for 0.08 mm and 0.1 mm voxels were greater (0.84 and 0.79, respectively) than the sensitivity and specificity values for 0.125 mm and 0.2 mm voxels (0.70 and 0.55, respectively). CONCLUSIONS: Despite the uncertain risk of bias found for the IV and OCS studies, smaller voxel and FOV sizes seem to provide more accurate VRF detection values when using CBCT. CLINICAL RELEVANCE: This information is crucial for supporting the clinician when prescribing CBCT in cases of a clinical suspicion of VRF, and contributes to the personalization of the CBCT prescription, thereby ensuring greater accuracy in the VRF diagnosis. Registration This protocol was registered at the PROSPERO database (International Prospective Register of Systematic Review) under registration number CRD42020210118.


Asunto(s)
Fracturas Óseas , Tomografía Computarizada de Haz Cónico Espiral , Fracturas de los Dientes , Humanos , Fracturas de los Dientes/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Sensibilidad y Especificidad , Tomografía Computarizada de Haz Cónico/métodos
4.
J Prosthet Dent ; 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37805289

RESUMEN

STATEMENT OF PROBLEM: Surface treatments for resin-ceramics have been developed to obtain a smooth surface and improve color stability. However, a consensus on the best treatment for these materials is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the color stability and roughness of glass-ceramics versus resin-ceramics with different surface treatments. MATERIAL AND METHODS: The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed, and the study was registered in the open science framework (OSF) for in vitro studies. The population, intervention, control, and outcome (PICO) question was "Is there a difference in color stability and roughness between resin-ceramic vs vitreous ceramics in different surface treatment protocols?" A literature search was performed in PubMed/MEDLINE, Embase, Web of Science, Scopus, Cochrane Library, and ProQuest databases up to January 2023. The Joanna Briggs Institute's critical assessment guidelines for quasi-experimental studies were used for quality assessment. The meta-analysis was based on the inverse variance (IV) method (α=.05). RESULTS: A total of 18 laboratory studies were published between 2015 and 2022, with a total of 2160 specimens, all of which were analyzed qualitatively. The meta-analysis indicated significantly less optical alteration for lithium disilicate ceramics (P<.01; MD: 2.69; 95% CI: 2.00-3.39; I²=89%, P<.01), even when compared with resin-ceramics with polish or sealants (P<.01; MD: 2.45; 95% CI: 1.59-3.30; I²=87%, P<.01) and (P<.01; MD: 3.24; 95% CI: 2.02-4.47; I²=89%, P<.01), while there was no significant difference in surface roughness (P=.08; MD: -0.71; CI 95%: -1.52 to 0.09; I²=87%, P<.01) (P=.33; MD: -0.31; CI 95%: -0.94 to 0.32; I²=87%, P<.01), respectively. CONCLUSIONS: Resin-ceramics that have been polished or treated with sealants have lower color stability than glazed glass-ceramics; however, they are similar in terms of surface roughness.

5.
Gen Dent ; 71(4): 58-62, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37358585

RESUMEN

Polyetheretherketone (PEEK) resin is a high-performance thermoplastic polymer that has been introduced as a possible candidate to replace metallic components in dental prostheses. The objective of this integrative review was to compare, through analysis of studies in the literature, the mechanical performance of removable partial denture frameworks and clasps manufactured with PEEK with the performance of cobalt-chromium (Co-Cr) frameworks and clasps. The guiding question was, "Does the use of PEEK as a substitute for Co-Cr alloys for the construction of removable partial denture frameworks result in better mechanical properties?" The PubMed/ MEDLINE, Embase, Web of Science, Scopus, and SciELO databases were searched for articles published through October 2021. The JBI Critical Appraisal Checklist for Quasi-Experimental Studies was used to assess the methodologic quality of the selected in vitro studies. A total of 208 articles were identified. After the exclusion of duplicates and articles that did not meet the inclusion criteria, 7 studies- -4 in vitro and 3 three-dimensional finite element analyses- -published between 2012 and 2021 were included in the integrative review. The appraisal checklist revealed that the reviewed studies had a low risk of bias and high methodologic quality. The results of the review showed that PEEK alloys have adequate mechanical properties for use in clasps and removable partial denture frameworks, but Co-Cr alloys exhibit better mechanical properties and are more suitable in most circumstances.


Asunto(s)
Dentadura Parcial Removible , Humanos , Abrazadera Dental , Aleaciones de Cromo , Polímeros , Polietilenglicoles/uso terapéutico , Cetonas
6.
J Chem Ecol ; 48(7-8): 660-669, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35653012

RESUMEN

In most commercial pine farms in southern Brazil, black capuchin causes damage to wood and financial losses when it removes bark from some pine species to feed upon underlying vascular tissues. Therefore, this study aimed to evaluate the variability of the primary metabolites of phloem saps from 10 different species of pine by NMR spectroscopy, as well as the aroma compounds using SPME-GC-MS. Each technique provided a different set of metabolites that we can correlate to monkey predilection. The PCA showed monosaccharide (detected by NMR) and α-pinene (pine-like and resinous flavor descriptors) as attractive compounds for monkeys. On the other hand, the low content of monosaccharide and the high content of ß-phellandrene (citrus odor descriptor) was observed in less attacked pine species (P. patula). The data fusion on primary metabolites and aroma compounds corroborated the individual analyses, complementing the comprehension of the monkey predilection. Thus, P. elliottii was an avoided tree even with high content of sugars possibly due to its high content of ß-phellandrene (citrus odor). The results are useful for further behavioral studies to determine the role that each highlighted metabolite plays in chemically mediated animal-plant interactions.


Asunto(s)
Citrus , Pinus , Animales , Citrus/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Monosacáridos/metabolismo , Floema/metabolismo , Pinus/química , Sapajus
7.
Genomics ; 113(6): 3523-3532, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34400240

RESUMEN

Serratia marcescens is a global spread nosocomial pathogen. This rod-shaped bacterium displays a broad host range and worldwide geographical distribution. Here we analyze an international collection of this multidrug-resistant, opportunistic pathogen from 35 countries to infer its population structure. We show that S. marcescens comprises 12 lineages; Sm1, Sm4, and Sm10 harbor 78.3% of the known environmental strains. Sm5, Sm6, and Sm7 comprise only human-associated strains which harbor smallest pangenomes, genomic fluidity and lowest levels of core recombination, indicating niche specialization. Sm7 and Sm9 lineages exhibit the most concerning resistome; blaKPC-2 plasmid is widespread in Sm7, whereas Sm9, also an anthropogenic-exclusive lineage, presents highest plasmid/lineage size ratio and plasmid-diversity encoding metallo-beta-lactamases comprising blaNDM-1. The heterogeneity of resistance patterns of S. marcescens lineages elucidated herein highlights the relevance of surveillance programs, using whole-genome sequencing, to provide insights into the molecular epidemiology of carbapenemase producing strains of this species.


Asunto(s)
Serratia marcescens , beta-Lactamasas , Antibacterianos , Humanos , Plásmidos/genética , Serratia marcescens/genética , Secuenciación Completa del Genoma , beta-Lactamasas/genética
8.
J Chem Inf Model ; 61(6): 2516-2522, 2021 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-34014674

RESUMEN

Natural products and their secondary metabolites are promising starting points for the development of drug prototypes and new drugs, as many current treatments for numerous diseases are directly or indirectly related to such compounds. State-of-the-art, curated, integrated, and frequently updated databases of secondary metabolites are thus highly relevant to drug discovery. The SistematX Web Portal, introduced in 2018, is undergoing development to address this need and documents crucial information about plant secondary metabolites, including the exact location of the species from which the compounds were isolated. SistematX also allows registered users to log in to the data management area and gain access to administrative pages. This study reports recent updates and modifications to the SistematX Web Portal, including a batch download option, the generation and visualization of 1H and 13C nuclear magnetic resonance spectra, and the calculation of physicochemical (drug-like and lead-like) properties and biological activity profiles. The SistematX Web Portal is freely available at http://sistematx.ufpb.br.


Asunto(s)
Productos Biológicos , Bases de Datos Factuales , Descubrimiento de Drogas , Espectroscopía de Resonancia Magnética , Plantas
9.
Gynecol Endocrinol ; 37(1): 15-20, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32538231

RESUMEN

METHODS: Thirty-one female C57BL/6J mice were divided into four groups: two were treated with subcutaneous dehydroepiandrosterone (DHEA) implants and divided into normal and hypercaloric diet (HFD). Two were control and divided into normal and HFD. Presence of insulin resistance, growth, and adipocyte markers expression of white and brown adipose tissues and growth and inflammatory cytokines expression of bone marrow adipose tissue were evaluated. RESULTS: Hypercaloric diet groups presented higher total weight gain and huge growth in all fat sites, except bone marrow. They also demonstrated greater expression of adipocyte markers in sites of white adipose tissue. DHEA + HFD group showed more insulin intolerance than all other groups. DHEA shows to abrogate AdipoQ expression in all fatty tissues. CONCLUSIONS: DHEA alone does not influence adipose tissue growth, but contributes to increased insulin resistance and influences the expression of adipokines. Proximal MAT showed different behavior from the other fat depot.


Asunto(s)
Tejido Adiposo/fisiopatología , Resistencia a la Insulina , Síndrome del Ovario Poliquístico/fisiopatología , Animales , Deshidroepiandrosterona , Modelos Animales de Enfermedad , Femenino , Ratones Endogámicos C57BL , Síndrome del Ovario Poliquístico/inducido químicamente
10.
Clin Oral Investig ; 25(8): 5077-5085, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33543383

RESUMEN

OBJECTIVES: To present an image processing framework to improve the detection of vertical root fractures (VRFs) in digital periapical radiography. MATERIALS AND METHODS: Thirty endodontically treated human teeth (15 of them fractured with a metal post inserted into them, and 15 for the control) were enclosed in a dry mandible and radiographed individually. The proposed framework was applied to the raw data, as a preprocessing step, and was composed of four stages: geometric adjustment and negative, denoising, adaptive contrast enhancement, and gamma correction. The contrast-to-noise ratio (CNR) and sharpness of the image's VRF region were used for the objective evaluation of the method. In addition, five examiners evaluated the original and enhanced images, using a 5-point scale to assess confidence. RESULTS: The objective results showed that the proposed framework increased the CNR of the VRF region by 173% compared to the standard preprocessing method provided by the detector's manufacturer. The results found by the human observers indicated that the area under the curve (AUC) and sensitivity of the diagnosis of VRF significantly increased by 4% and 17% (p ≤ 0.05), respectively, when the examiners evaluated the image with the proposed method concomitantly with the image available in the commercial software. However, the specificity was reduced. CONCLUSIONS: The proposed image processing framework can be used as an additional tool to that provided by the manufacturer to increase the sensitivity and AUC of the diagnosis of VRF. CLINICAL RELEVANCE: The proposed method can be easily used in clinical practice to aid VRF detection, since it does not incur high computational costs and does not increase the radiation dose applied to the patient.


Asunto(s)
Fracturas de los Dientes , Diente no Vital , Tomografía Computarizada de Haz Cónico , Humanos , Radiografía Dental Digital , Fracturas de los Dientes/diagnóstico por imagen , Raíz del Diente
11.
Clin Oral Investig ; 25(3): 1099-1105, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32591867

RESUMEN

OBJECTIVES: This study evaluated factors associated with vertical root fracture in endodontically treated teeth, using a cone-beam computed tomography (CBCT) image database. MATERIALS AND METHODS: The sample for this case-control study consisted of 81 CBCT scans of teeth with vertical root fracture (VRF) and 81 CBCT scans of non-fractured teeth, matched by age, sex, and tooth position. The analyzed variables included dentin thickness, an intraradicular post, an adjacent implant, and a missing adjacent tooth. Student's t test test was used to compare the quantitative variables. The chi-square test was used to compare the categorical variables. Logistic regression was performed to evaluate the association between the presence of VRF and the independent factors assessed. RESULTS: The mean dentin thickness of fractured teeth was 1.3 mm, whereas that of non-fractured ones was 1.5 mm (p < 0.001). There was no difference between the fractured and non-fractured groups, regarding implant frequency or missing adjacent tooth (p > 0.05). There were a significantly larger number of teeth with posts in the fractured versus non-fractured group (p = 0.007). However, dentin thickness ≤ 1.3 mm was the only factor associated with VRF in the multiple regression model (OR = 3.60, 95%CI = 1.76-7.37). CONCLUSIONS: Dentin thickness may influence the development of VRF. Dentin thickness ≤ 1.3 mm is associated with a greater likelihood of fracture than ≥ 1.4 mm. CLINICAL RELEVANCE: This study suggests there may be a minimum amount of safe dentin thickness that should be preserved after endodontic instrumentation.


Asunto(s)
Fracturas de los Dientes , Diente no Vital , Estudios de Casos y Controles , Tomografía Computarizada de Haz Cónico , Dentina/diagnóstico por imagen , Humanos , Factores de Riesgo , Fracturas de los Dientes/diagnóstico por imagen , Fracturas de los Dientes/etiología , Raíz del Diente/diagnóstico por imagen , Diente no Vital/diagnóstico por imagen
12.
Clin Oral Investig ; 25(7): 4329-4340, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34050426

RESUMEN

OBJECTIVES: The aim of this systematic review was to examine the evidence of the binary histologic grading system capacity for predicting malignant transformation and to compare it with that of the WHO systems. MATERIAL AND METHODS: A systematic review was conducted, using PubMed, EMBASE, LILACS, Web of Science, Scopus, and LIVIVO databases without any language or timeframe restrictions. Studies were included if they compared the binary and the WHO histologic grading systems in the prediction of malignant transformation of oral epithelial dysplasia (OED). RESULTS: The capacity of the WHO and binary grading systems to predict malignant transformation ranged from 16 to 80% and from 5 to 80%, respectively. The pooled malignant transformation rate of lesions classified as severe dysplasia or carcinoma in situ by the WHO grading was 40% (95% confidence interval (CI), 0.02-0.87; I2 = 92%; P = 0.00), while the corresponding value for lesions classified as high-risk by the binary grading system was 31% (95% CI, 0.00-0.84; I2 = 97%; P = 0.00). Overall, there was no significant difference in prognostication accuracy between the WHO and the binary systems (odds ratio = 2.02; 95% CI, 0.88-4.64). CONCLUSIONS: Although some studies suggest that the binary system is associated with lower inter-rater variability when grading OED, the evidence remains inconclusive on whether this system is superior to that of the WHO at predicting malignant transformation. CLINICAL RELEVANCE: The reproducibility of the binary system has the potential to be better for prognostic purposes. However, there is no high-quality evidence to confirm if this advantage may assist clinicians in decision-making.


Asunto(s)
Neoplasias de la Boca , Lesiones Precancerosas , Transformación Celular Neoplásica , Humanos , Leucoplasia Bucal , Reproducibilidad de los Resultados , Organización Mundial de la Salud
13.
J Prosthet Dent ; 126(2): 223.e1-223.e8, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34099274

RESUMEN

STATEMENT OF PROBLEM: Whether providing an occlusal device for a patient with bruxism and an implant-supported fixed dental prosthesis leads to improved biomechanics is unclear. PURPOSE: The purpose of this 3D finite element analysis (FEA) study was to evaluate the biomechanical behavior of 3-unit implant-supported prostheses under parafunctional forces with and without an occlusal device. MATERIALS AND METHODS: Eight 3D models consisting of a posterior (type IV) maxillary bone block with 3 external hexagon implants (Ø4.0×7.0 mm) and 3-unit implant-supported prostheses with different crown connections (splinted or unsplinted) and an occlusal device under functional and parafunctional loading were simulated. The abutment screws were evaluated by von Mises stress maps, and the bone tissue by maximum principal stress and microstrain maps by using a finite element software program. RESULTS: An occlusal device improved the biomechanical behavior of the prostheses by reducing stress in the abutment screws and stress and strain in the bone tissue. However, the use of an occlusal device was not sufficiently effective to negate the biomechanical benefit of splinting. CONCLUSIONS: The use of splinted crowns in the posterior maxillary region with an occlusal device was the most effective method of reducing stress in the abutment screws and stress and strain in the bone tissue when parafunction was modeled.


Asunto(s)
Implantes Dentales , Prótesis Dental de Soporte Implantado , Fenómenos Biomecánicos , Coronas , Diseño de Prótesis Dental , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Estrés Mecánico
14.
World J Microbiol Biotechnol ; 37(7): 112, 2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-34081209

RESUMEN

Grapevine cultivars are distributed worldwide, nevertheless the fermentation of its grape berries renders distinct wine products that are highly associated to the local fungal community. Despite the symbiotic association between wine and the fungal metabolism, impacting both the terroir and mycotoxin production, few studies have explored the vineyard ecosystem fungal community using both molecular marker sequencing and mycotoxin production assessment. In this study, we investigated the fungal community of three grapevine cultivars (Vitis vinifera L.) in two tropical vineyards. Illumina MiSeq sequencing was performed on two biocompartments: grape berries (GB) and grapevine soil (GS); yielding a total of 578,495 fungal internal transcribed spacer 1 reads, which were used for taxonomic classification. GB and GS fungal communities were mainly constituted by Ascomycota phylum. GS harbors a significant richer and more diverse fungal community than GB. Among GB samples, Syrah grape berries exclusively shared fungal community included wine-associated yeasts (e.g. Saccharomycopsis vini) that may play key roles in wine terroir. Mycotoxin production assessment revealed the high potential of Aspergillus section Flavi and Penicillium section Citrina isolates to produce aflatoxin B1-B2 and citrinin, respectively. This is the first study to employ next-generation sequencing to investigate vineyard associated fungal community in Brazil. Our findings provide valuable insights on the available tools for fungal ecology assessment applied to food products emphasizing the coexistence between classical and molecular tools.


Asunto(s)
ADN Espaciador Ribosómico/genética , Hongos/clasificación , Micotoxinas/metabolismo , Análisis de Secuencia de ADN/métodos , Vitis/microbiología , Brasil , ADN de Hongos/genética , Granjas , Hongos/genética , Hongos/aislamiento & purificación , Hongos/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Microbiología del Suelo , Clima Tropical
15.
J Prosthodont ; 30(2): 119-127, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32893938

RESUMEN

PURPOSE: To evaluate implant and prosthetic survival rates of full-arch rehabilitations retained by three implants in patients with edentulous mandibles. MATERIALS AND METHODS: This systematic review was developed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The focused question was: Are fixed mandibular 3-implant retained prostheses safe and predicable for full-arch mandibular prostheses? The Medline/PubMed and Cochrane Library databases were used to conduct the systematic search for clinical trials on fixed mandibular 3-implant retained prostheses published between 1999 and 2020. Only English-language studies that presented information on implant and prosthetic survival were included. RESULTS: A total of 302 studies were identified, of which 13 addressed the inclusion criteria. Additionally, 574 participants were included in these studies. As reported, 73 (4.57%) of 1596 implants failed, with a survival rate of 95.43%. In addition, the mean survival rate of the presented prostheses was 89.66%. The mean marginal bone loss was 1.09 mm. CONCLUSION: Within the limitations of the present review, implant and prosthetic survival rates of fixed mandibular 3-implant retained prostheses were similar to those of full-arch mandibular prostheses retained by four or more implants. Further research exploring the topic is necessary.


Asunto(s)
Implantes Dentales , Prótesis Mandibular , Prótesis Dental de Soporte Implantado , Fracaso de la Restauración Dental , Estudios de Seguimiento , Humanos , Mandíbula/cirugía
16.
Arch Virol ; 165(6): 1267-1278, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32333117

RESUMEN

Giant viruses of amoebas are a remarkable group of viruses. In addition to their large size and peculiar structures, the genetic content of these viruses is also special. Among the genetic features of these viruses that stand out is the presence of coding regions for elements involved in translation, a complex biological process that occurs in cellular organisms. No viral genome described so far has such a complex genetic arsenal as those of giant viruses, which code for several of these elements. Currently, tupanviruses have the most complete set of translation genes in the known virosphere. In this review, we have condensed what is currently known about translation genes in different groups of giant viruses and theorize about their biological importance, origin, and evolution, and what might possibly be found in the coming years.


Asunto(s)
Virus Gigantes/genética , Mimiviridae/genética , Amoeba/virología , Evolución Molecular , Genoma Viral , Virus Gigantes/patogenicidad , Especificidad del Huésped/genética , Mimiviridae/metabolismo , Mimiviridae/ultraestructura , Filogenia , Biosíntesis de Proteínas , Proteoma/genética , ARN Ribosómico 16S/genética , ARN Viral/genética
17.
Plant Mol Biol ; 101(3): 269-296, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31338671

RESUMEN

KEY MESSAGE: The first transcriptome coupled to metabolite analyses reveals major trends during acerola fruit ripening and shed lights on ascorbate, ethylene signalling, cellular respiration, sugar accumulation, and softening key regulatory genes. Acerola is a fast growing and ripening fruit that exhibits high amounts of ascorbate. During ripening, the fruit experience high respiratory rates leading to ascorbate depletion and a quickly fragile and perishable state. Despite its growing economic importance, understanding of its developmental metabolism remains obscure due to the absence of genomic and transcriptomic data. We performed an acerola transcriptome sequencing that generated over 600 million reads, 40,830 contigs, and provided the annotation of 25,298 unique transcripts. Overall, this study revealed the main metabolic changes that occur in the acerola ripening. This transcriptional profile linked to metabolite measurements, allowed us to focus on ascorbate, ethylene, respiration, sugar, and firmness, the major metabolism indicators for acerola quality. Our results suggest a cooperative role of several genes involved in AsA biosynthesis (PMM, GMP1 and 3, GME1 and 2, GGP1 and 2), translocation (NAT3, 4, 6 and 6-like) and recycling (MDHAR2 and DHAR1) pathways for AsA accumulation in unripe fruits. Moreover, the association of metabolites with transcript profiles provided a comprehensive understanding of ethylene signalling, respiration, sugar accumulation and softening of acerola, shedding light on promising key regulatory genes. Overall, this study provides a foundation for further examination of the functional significance of these genes to improve fruit quality traits.


Asunto(s)
Ácido Ascórbico/química , Etilenos/química , Frutas/fisiología , Malpighiaceae/genética , Malpighiaceae/metabolismo , Transcriptoma , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Proteínas de Plantas/metabolismo , Análisis de Componente Principal , Transducción de Señal
18.
J Virol ; 92(2)2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-29118120

RESUMEN

The inclusion of Mimiviridae members in the putative monophyletic nucleocytoplasmic large DNA virus (NCLDV) group is based on genomic and phylogenomic patterns. This shows that, along with other viral families, they share a set of genes known as core or "hallmark genes," including the gene for the major capsid protein (MCP). Although previous studies have suggested that the maturation of mimivirus MCP transcripts is dependent on splicing, there is little information about the processing of this transcript in other mimivirus isolates. Here we report the characterization of a new mimivirus isolate, called Kroon virus (KV) mimivirus. Analysis of the structure, synteny, and phylogenetic relationships of the MCP genes in many mimivirus isolates revealed a remarkable variation at position and types of intronic and exonic regions, even for mimiviruses belonging to the same lineage. In addition, sequencing of KV and Acanthamoeba polyphaga mimivirus (APMV) MCP transcripts has shown that inside the family, even related giant viruses may present different ways to process the MCP mRNA. These results contribute to the understanding of the genetic organization and evolution of the MCP gene in mimiviruses.IMPORTANCE Mimivirus isolates have been obtained by prospecting studies since 2003. Based on genomic and phylogenomic studies of conserved genes, these viruses have been clustered together with members of six other viral families. Although the major capsid protein (MCP) gene is an important member of the so-called "hallmark genes," there is little information about the processing and structure of this gene in many mimivirus isolates. In this work, we have analyzed the structure, synteny, and phylogenetic relationships of the MCP genes in many mimivirus isolates; these genes showed remarkable variation at position and types of intronic and exonic regions, even for mimiviruses belonging to the same lineage. These results contribute to the understanding of the genetic organization and evolution of the MCP gene in mimiviruses.


Asunto(s)
Proteínas de la Cápside/genética , Evolución Molecular , Regulación Viral de la Expresión Génica , Mimiviridae/genética , Empalme del ARN , Transcripción Genética , Genoma Viral , Mimiviridae/clasificación , Mimiviridae/aislamiento & purificación , Mimiviridae/ultraestructura , Filogenia , ARN Viral , Replicación Viral , Microbiología del Agua
19.
Chem Biodivers ; 16(6): e1900050, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30980460

RESUMEN

The development of studies on emissions of volatile organic compounds (VOCs) by inflorescence of oil palms deserves a special attention regarding the importance to reproduction success and for increase of production. This study aimed to evaluate metabolic profiling of VOCs expelled by male and female inflorescences of different oil palm species (African oil palm, Amazonian Caiaué and the interspecific hybrid BRS-Manicoré), associating the composition variability with main pollinators to improve the comprehension of the plant-insect relationship. The phenylpropanoids, terpenoids and the aliphatic hydrocarbons were predominant classes detected in inflorescences of oil palms and the major compound was estragole. This result may be correlated with attraction of Elaidobius pollinators, since these insects were not attracted by Caiaué, which emitted estragole only in trace amounts. However, Caiaué and the hybrid species were visited by other native species whose frequencies were low and their success as pollinators could not be expected.


Asunto(s)
Aceite de Palma/química , Compuestos Orgánicos Volátiles/química , Animales , Arecaceae/química , Arecaceae/metabolismo , Conducta Animal/efectos de los fármacos , Análisis por Conglomerados , Femenino , Cromatografía de Gases y Espectrometría de Masas , Hidrocarburos/química , Hidrocarburos/farmacología , Masculino , Aceite de Palma/metabolismo , Polinización , Terpenos/química , Terpenos/farmacología , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/farmacología , Gorgojos/fisiología
20.
Rev Med Chil ; 147(12): 1613-1620, 2019 Dec.
Artículo en Español | MEDLINE | ID: mdl-32186625

RESUMEN

Background The consumption of illicit drugs in Chile has increased over the years generating abuse and dependence problems and becoming a public health problem. Aim To build and disseminate a figure in which health personnel can quickly visualize illicit drugs and their common names, and thus be able to associate them with the effects and risks that are expected in the patient. Material and Methods A bibliographic review and compilation of information obtained from dealers and drug abusers. Results A figure and a table were developed. The former illustrates the classification and common names of drugs, while the second indicates the mechanisms of action and effects expected in the body according to each drug of abuse. Conclusions Illicit drugs have several popular names and various mechanisms of action. When confronting drug consumption this information is crucial to provide an adequate treatment and withdrawal management. However, it is important to keep in mind that this work only represents a management guide and that treatment should always focus on the condition and clinical manifestations of the patient.


Asunto(s)
Drogas Ilícitas/clasificación , Trastornos Relacionados con Sustancias , Terminología como Asunto , Chile , Humanos , Cultura Popular
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