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1.
Nicotine Tob Res ; 26(3): 333-341, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-37589502

RESUMEN

INTRODUCTION: Nicotine dependence follows a chronic course that is characterized by repeated relapse, often driven by acute stress and rewarding memories of smoking retrieved from related contexts. These two triggers can also interact, with stress influencing retrieval of contextual memories. However, the roles of these processes in nicotine dependence remain unknown. AIMS AND METHODS: We investigated how acute stress biases memory for smoking-associated contexts among smokers (N = 65) using a novel laboratory paradigm. On day 1, participants formed associations between visual stimuli of items (either neutral or related to smoking) and places (background scenes). On day 2 (24 hours later), participants were exposed to an acute laboratory-based stressor (socially evaluated cold pressor test; N = 32) or a matched control condition (N = 33) prior to being tested on their memory recognition and preferences for each item and place. We distinguished the accuracy of memory into specific (ie, precisely correct) or gist (ie, lure items with similar content) categories. RESULTS: Results demonstrated that the stressor significantly induced physiological and subjective perceived stress responses, and that stressed smokers exhibited a memory bias in favor of smoking-related items. In addition, the stressed group displayed greater preference for both smoking-related items and places that had been paired with the smoking-related items. We also found suggestive evidence that stronger smoking-related memory biases were associated with more severe nicotine dependence (ie, years of smoking). CONCLUSIONS: These results highlight the role of stress in biasing smokers toward remembering contexts associated with smoking, and amplifying their preference for these contexts. IMPLICATIONS: The current study elucidates the role of acute stress in promoting memory biases favoring smoking-related associations among smokers. The results suggest that the retrieval of smoking-biased associative memory could be a crucial factor in stress-related nicotine seeking. This may lead to a potential intervention targeting the extinction of smoking-related context memories as a preventive strategy for stress-induced relapse.


Asunto(s)
Tabaquismo , Humanos , Fumadores , Fumar , Nicotina/farmacología , Recurrencia
2.
Psychol Sci ; 34(10): 1146-1162, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37682597

RESUMEN

Generalizing from past experiences to novel situations is critical for adaptive behavior, whereas overgeneralization can promote maladaptive responses (e.g., context-inappropriate fear in anxiety). Here, we propose that overgeneralizing alcohol-related associations characterizes risky drinking. We conducted two online experiments assessing generalization of alcohol-related gains (Study 1) and losses (Study 2) among individuals who engaged in light or risky patterns of drinking (Study 1: N = 88, 24-44 years old; Study 2: N = 87, 21-44 years old). After learning to associate cards with alcohol and non-alcohol-related outcomes, participants chose whether to play with cards varying in perceptual similarity to those shown during conditioning. Finally, participants completed a surprise recognition memory test for all outcomes. Although both groups showed comparable conditioning, we found that risky drinkers overgeneralized alcohol-related gains and losses. Risky drinkers also showed a bias toward recognizing alcohol-related images. These results indicate a novel role for overgeneralization of alcohol-related gains and losses as a mechanism associated with risky drinking.


Asunto(s)
Consumo de Bebidas Alcohólicas , Etanol , Humanos , Adulto Joven , Adulto , Asunción de Riesgos , Miedo , Ansiedad
3.
Glob Chang Biol ; 24(12): 5815-5827, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30230661

RESUMEN

Rising atmospheric CO2 concentration directly stimulates plant productivity and affects nutrient dynamics in the soil. However, the influence of CO2 enrichment on soil bacterial communities remains elusive, likely due to their complex interactions with a wide range of plant and soil properties. Here, we investigated the bacterial community response to a decade long preindustrial-to-future CO2 gradient (250-500 ppm) among three contrasting soil types using 16S rRNA gene amplicon sequencing. In addition, we examined the effect of seasonal variation and plant species composition on bacterial communities. We found that Shannon index (H') and Faith's phylogenetic diversity (PD) did not change in response to the CO2 gradient (R2  = 0.01, p > 0.05). CO2 gradient and season also had a negligible effect on overall community structure, although silty clay soil communities were better structured on a CO2 gradient (p < 0.001) among three soils. Similarly, CO2 gradient had no significant effect on the relative abundance of different phyla. However, we observed soil-specific variation of CO2 effects in a few individual families. For example, the abundance of Pirellulaceae family decreased linearly with CO2 gradient, but only in sandy loam soils. Conversely, the abundance of Micromonosporaceae and Gaillaceae families increased with CO2 gradient in clay soils. Soil water content (SWC) and nutrient properties were the key environmental constraints shaping bacterial community structure, one manifestation of which was a decline in bacterial diversity with increasing SWC. Furthermore, the impact of plant species composition on community structure was secondary to the strong influence of soil properties. Taken together, our findings indicate that bacterial communities may be largely unresponsive to indirect effects of CO2 enrichment through plants. Instead, bacterial communities are strongly regulated by edaphic conditions, presumably because soil differences create distinct environmental niches for bacteria.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Dióxido de Carbono/análisis , Pradera , Microbiología del Suelo , Suelo/química , Bacterias/genética , Filogenia , Plantas/genética , ARN Bacteriano , ARN Ribosómico 16S/genética , Texas
4.
Microb Ecol ; 76(4): 856-865, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29569048

RESUMEN

Phosphorus (P) is a nutrient of primary importance in all living systems, and it is especially important in streams and rivers which are sensitive to anthropogenic P inputs and eutrophication. Microbes are accepted as the primary mineralizers and solubilizers of P improving bioavailability for organisms at all trophic levels. Here, we use a genomics approach with metagenome sequencing of 24 temperate streams and rivers representing a total P (TP) gradient to identify relationships between functional genes, functional gene groupings, P, and organisms within the P biogeochemical cycle. Combining information from network analyses, functional groupings, and system P levels, we have constructed a System Relational Overview of Gene Groupings (SROGG) which is a cohesive system level representation of P cycle gene and nutrient relationships. Using SROGG analysis in concert with other statistical approaches, we found that the compositional makeup of P cycle genes is strongly correlated to environmental P whereas absolute abundance of P genes shows no significant correlation to environmental P. We also found orthophosphate (PO43-) to be the dominant factor correlating with system P cycle gene composition with little evidence of a strong organic phosphorous correlation present even in more oligotrophic streams.


Asunto(s)
Archaea/metabolismo , Bacterias/metabolismo , Metagenoma , Metagenómica , Fósforo/metabolismo , Ríos/microbiología , Contaminantes Químicos del Agua/metabolismo , Archaea/genética , Arkansas , Bacterias/genética , Genes Arqueales/genética , Genes Bacterianos , Oklahoma
5.
Microb Ecol ; 75(1): 64-73, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28721504

RESUMEN

Phosphorus (P) is a key biological element with important and unique biogeochemical cycling in natural ecosystems. Anthropogenic phosphorus inputs have been shown to greatly affect natural ecosystems, and this has been shown to be especially true of freshwater systems. While the importance of microbial communities in the P cycle is widely accepted, the role, composition, and relationship to P of these communities in freshwater systems still hold many secrets. Here, we investigated combined bacterial and archaeal communities utilizing 16S ribosomal RNA (rRNA) gene sequencing and computationally predicted functional metagenomes (PFMs) in 25 streams representing a strong P gradient. We discovered that 16S rRNA community structure and PFMs demonstrate a degree of decoupling between structure and function in the system. While we found that total phosphorus (TP) was correlated to the structure and functional capability of bacterial and archaeal communities in the system, turbidity had a stronger, but largely independent, correlation. At TP levels of approximately 55 µg/L, we see sharp differences in the abundance of numerous ecologically important taxa related to vegetation, agriculture, sediment, and other ecosystem inhabitants.


Asunto(s)
Archaea/aislamiento & purificación , Bacterias/aislamiento & purificación , Microbiota , Fósforo/análisis , Ríos/microbiología , Archaea/clasificación , Archaea/genética , Archaea/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Biodiversidad , Ecosistema , Metagenoma , Fósforo/metabolismo , Filogenia , Ríos/química
6.
J Oral Maxillofac Surg ; 75(11): 2441.e1-2441.e13, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28826784

RESUMEN

PURPOSE: To evaluate the accuracy of virtual surgical simulation combined with digital teeth alignment and the applicability of this technique to the diagnosis and establishment of a 3-dimensional (3D) visualized treatment objective for orthognathic surgery by comparing virtual simulation images with actual post-treatment images. MATERIALS AND METHODS: This retrospective study included patients who underwent computed tomography (CT) before and after treatment. The 3D digital images were constructed from the initial CT images and dental cast scan data, and virtual surgical simulation combined with digital teeth alignment was performed. Accuracy of the virtual simulation was analyzed by comparing the distances of skeletal and dental landmarks in the horizontal, sagittal, and coronal reference planes with those on post-treatment images using the Wilcoxon signed rank test. Intraclass correlation coefficients were calculated to evaluate the degree of concordance between the 2 images. RESULTS: The study sample included 11 patients (mean age, 18.8 yr). Most landmarks had differences smaller than 2 mm in the 3 reference planes between virtual simulation and post-treatment images; these differences were not statistically significant (P > .05). Most skeletal landmarks, except the A point, B point, and gonion, showed normal to high concordance between the virtual simulation and post-treatment images in the 3 reference planes (P < .05); dental landmarks exhibited a broad range of concordance. CONCLUSION: The 3D virtual surgical simulation combined with digital teeth alignment using pretreatment CT images yielded results sufficiently accurate to be used for the diagnosis and establishment of visualized treatment objectives for orthognathic surgery.


Asunto(s)
Simulación por Computador , Imagenología Tridimensional , Maloclusión de Angle Clase III/diagnóstico por imagen , Maloclusión de Angle Clase III/cirugía , Procedimientos Quirúrgicos Ortognáticos/métodos , Cirugía Asistida por Computador , Tomografía Computarizada por Rayos X , Diente/diagnóstico por imagen , Adolescente , Femenino , Humanos , Masculino , Proyectos Piloto , Estudios Retrospectivos
7.
J Oral Maxillofac Surg ; 73(1): 134-51, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25315304

RESUMEN

In orthognathic surgery, it is important to have a planned postoperative occlusion. A 3-dimensional preoperative simulation, based on 3-dimensional optically scanned occlusion data, can predict how the planned postoperative occlusion will affect the maxilla-mandibular relationship that results from orthognathic surgery. In this study we modified the planned postoperative occlusion, based on computer-aided design/computer-aided manufacturing-engineered preoperative surgical simulations. This modification made it possible to resolve the facial asymmetry of the patient successfully with a simple bilateral intraoral vertical ramus osteotomy and no additional maxillary or mandibular surgery.


Asunto(s)
Simulación por Computador , Diseño Asistido por Computadora , Oclusión Dental , Procedimientos Quirúrgicos Ortognáticos/métodos , Planificación de Atención al Paciente , Cirugía Asistida por Computador/métodos , Cefalometría/métodos , Asimetría Facial/cirugía , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Maloclusión de Angle Clase III/cirugía , Maloclusión de Angle Clase III/terapia , Mandíbula/cirugía , Osteotomía Mandibular/instrumentación , Osteotomía Mandibular/métodos , Modelos Anatómicos , Métodos de Anclaje en Ortodoncia/métodos , Impresión Tridimensional , Prognatismo/cirugía , Tomografía Computarizada por Rayos X/métodos , Técnicas de Movimiento Dental/métodos , Adulto Joven
8.
J Oral Maxillofac Surg ; 72(10): 2032-42, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24780609

RESUMEN

PURPOSE: Stereolithographic guidance, increasingly used in orthognathic surgery, has not been completely verified for genioplasty. This study compared the accuracy of manual measurement with that of a stereolithographic guide in vitro. MATERIALS AND METHODS: Thirty rapid prototype (RP) mandibular models (15 pairs) were included in the experimental (stereolithographic) and control (manual) groups (15 each). Surgical simulation was performed in the 2 groups by advancing the chin 5 mm and then vertically reducing the chin 5 mm using Mimics software. In the stereolithographic group, genioplasty was performed on mandibular RP models using a 3-dimensionally printed surgical guide based on surgical simulation results. In the control group, it was performed using an osteotomy line drawn according to simulation measurements. For the 2 groups, anterior horizontal transverse error and anterior and posterior vertical errors were compared, as were data from the osteotomized chin segment and the preoperative surgical simulation. Positional difference error was calculated and the differences were evaluated with t tests. RESULTS: For advancement genioplasty, the absolute anterior transverse error value was 0.47 ± 0.35 (mean ± standard deviation) with the stereolithographic guide, less than with the manual method (0.77 ± 0.45; P = .001). For reduction genioplasty, the absolute anterior vertical error value was 0.27 ± 0.23 mm with the stereolithographic guide versus 0.58 ± 0.49 mm with the manual method (P < .001). CONCLUSION: Use of a stereolithographic surgical guide increased accuracy, but the difference in mean error values between methods was only approximately 0.3 mm. The superior accuracy may not be compelling in favor of stereolithographic surgical guides.


Asunto(s)
Simulación por Computador , Diseño Asistido por Computadora , Mentoplastia/métodos , Interfaz Usuario-Computador , Cefalometría/métodos , Mentón/anatomía & histología , Mentón/cirugía , Tomografía Computarizada de Haz Cónico/métodos , Mentoplastia/instrumentación , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Mandíbula/anatomía & histología , Mandíbula/cirugía , Osteotomía Mandibular/instrumentación , Modelos Anatómicos , Planificación de Atención al Paciente , Cirugía Asistida por Computador/instrumentación , Cirugía Asistida por Computador/métodos
9.
J Craniofac Surg ; 25(6): 2051-5, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25377965

RESUMEN

BACKGROUND: Three-dimensional printing and computer-assisted surgery demand a high-precision three-dimensional mesh model created from computed tomography (CT) imaging data using an image-based meshing algorithm. We aimed to evaluate the three-dimensional geometric accuracy of surface meshes produced from CT images with commercially available software packages. METHODS: The CT images were acquired for 3 human dry skulls and 10 manufactured plastic skulls. Four commercially available software packages were used to produce the surface meshes in stereolithography (STL) file format. These CT-based STL surface meshes were registered and compared with three-dimensional optical-scanned reference mesh surface for evaluating the accuracy of the STL mesh produced with each software package. RESULTS: The surface geometries produced by the CT-image-based meshing process were all relatively accurate; differences from the three-dimensional optical-scanned data were in the voxel or subvoxel range. However, when comparisons with the three-dimensional optical-scanned surface data were performed in individual anatomic regions, we found significantly different accuracies of the CT-based STL surface meshes produced by the different software packages. CONCLUSIONS: We found that all 4 software packages showed reasonably good meshing accuracies for clinical use. However, the range of errors inherent in the CT-image-based meshing process demands that caution should be taken in selecting and manipulating the software to avoid potential errors in specific clinical applications.


Asunto(s)
Tomografía Computarizada de Haz Cónico/normas , Imagenología Tridimensional/normas , Cráneo/diagnóstico por imagen , Algoritmos , Cadáver , Humanos , Imagenología Tridimensional/métodos , Cráneo/cirugía , Programas Informáticos/normas , Cirugía Asistida por Computador/métodos
10.
J Appl Psychol ; 109(3): 386-401, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37856408

RESUMEN

Decades of negotiations research has emphasized the importance of having alternatives. Negotiators with high-value outside offers tend to have greater power and claim higher values in the focal negotiation. We extend this line of work by proposing that the source of alternatives-that is, who negotiators receive an alternative offer from-can significantly shape their negotiation behavior and outcomes. Specifically, we examine how negotiators' behavior changes when they face a counterpart who has an offer from their rival. Four studies demonstrate that this situation enhances negotiators' motivation to outperform their counterpart's alternative by reaching an agreement with the counterpart. This in turn leads the focal negotiator to make less aspirational first offers and eventually claim less value in final agreements. Our findings highlight the importance of considering the existing relationships among actors directly and indirectly involved in a negotiation, reveal a novel motive that can guide negotiators' behavior and outcomes, and uncover a previously unexplored negotiation strategy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Negociación , Humanos
11.
Imaging Sci Dent ; 54(1): 93-104, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38571777

RESUMEN

Chronic nonbacterial osteomyelitis (CNO) is histologically characterized by nonspecific osteitis. This inflammatory disorder, which lacks an infectious origin, typically presents with chronic pain and swelling at the affected site that can persist for months or even years. However, it is rare for CNO to affect the mandible. A 10-year-old girl presented with a primary complaint of pain in her left mandible. She had no significant medical or dental history. On examination, swelling was visible on the left buccal side, and imaging revealed radiolucent bone deterioration within the left mandible. This case report presents the radiological changes observed over a 12-year follow-up period. Variations in radiopacity, radiolucency, and periosteal reactions were noted periodically. This case highlights the radiological characteristics and findings that are crucial for the diagnosis of CNO, a condition for which no clear diagnostic criteria are currently available.

12.
Arch Oral Biol ; 164: 105999, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38815512

RESUMEN

OBJECTIVE: The aim of this study was to understand the temporal and spatial distribution of canonical endochondral ossification (CEO) and non-canonical endochondral ossification (NCEO) of the normal growing rat condyle, and to evaluate their histomorphological changes following the simultaneous hypotrophy of the unilateral masticatory closing muscles with botulinum toxin (BTX). DESIGN: 46 rats at postnatal 4 weeks were used for the experiment and euthanized at postnatal 4, 8, and 16 weeks. The right masticatory muscles of rats in experimental group were injected with BTX, the left being injected with saline as a control. The samples were evaluated using 3D morphometric, histological, and immunohistochemical analysis with three-dimensional regional mapping of endochondral ossifications. RESULTS: The results showed that condylar endochondral ossification changed from CEO to NCEO at the main articulating surface during the experimental period and that the BTX-treated condyle presented a retroclined smaller condyle with an anteriorly-shifted narrower articulating surface. This articulating region showed a thinner layer of the endochondral cells, and a compact distribution of flattened cells. These were related to the load concentration, decreased cellular proliferation with thin cellular layers, reduced extracellular matrix, increased cellular differentiation toward the osteoblastic bone formation, and accelerated transition of the ossification types from CEO to NCEO. CONCLUSION: The results suggest that endochondral ossification under loading tended to show more NCEO, and that masticatory muscular hypofunction by BTX had deleterious effects on endochondral bone formation and changed the condylar growth vector, resulting in a retroclined, smaller, asymmetrical, and deformed condyle with thin cartilage.


Asunto(s)
Cóndilo Mandibular , Músculos Masticadores , Osteogénesis , Animales , Cóndilo Mandibular/efectos de los fármacos , Cóndilo Mandibular/crecimiento & desarrollo , Ratas , Osteogénesis/efectos de los fármacos , Músculos Masticadores/efectos de los fármacos , Ratas Wistar , Toxinas Botulínicas/farmacología , Inmunohistoquímica , Masculino , Toxinas Botulínicas Tipo A/farmacología
13.
J Oral Maxillofac Surg ; 71(2): 366-75, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22695020

RESUMEN

PURPOSE: The aim of this study was to verify the accuracy of 2 registration methods (marker-based registration and marker-free registration) during mandibular navigation surgery. MATERIALS AND METHODS: Two point-to-point registration methods (marker-based registration and marker-free registration) were tested using software and navigation equipment: 1) 3 implanted orthodontic screws and 2) 3 anatomic points on the cusp tips of the teeth (central incisor and first molars bilaterally). RESULTS: For the navigation equipment, the 3-point matching method of screw references was more accurate for all anatomic areas except the coronoid process and second premolar alveolar area. The registration error was largest for the condyle area. Errors were larger than 2.0 mm in the condyle, condyle neck, sigmoid notch, coronoid process, posterior border, lingula, and angle areas. In the oblique ridge, mental foramen, and dentoalveolar areas, the registration error using screws was smaller than 1.5 mm. For the software, tooth cusp references were more accurate for anatomic areas such as the mental foramen and dentoalveolar areas, but not the molar area. In all cases, the registration error was smaller than 1.0 mm, and that for the first molar was similar between the tooth tip overlap and the screw overlap. CONCLUSIONS: Registration using screws generally was more accurate than registration using tooth cusps for mandibular navigation surgery. However, tooth tip references can be used for registration in dentoalveolar surgery.


Asunto(s)
Marcadores Fiduciales , Mandíbula/cirugía , Cirugía Asistida por Computador/estadística & datos numéricos , Proceso Alveolar/anatomía & histología , Puntos Anatómicos de Referencia/anatomía & histología , Diente Premolar/anatomía & histología , Tornillos Óseos , Diente Canino/anatomía & histología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Incisivo/anatomía & histología , Cóndilo Mandibular/anatomía & histología , Diente Molar/anatomía & histología , Métodos de Anclaje en Ortodoncia/instrumentación , Programas Informáticos , Cirugía Asistida por Computador/instrumentación , Cirugía Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Ápice del Diente/anatomía & histología , Corona del Diente/anatomía & histología
14.
Oral Radiol ; 39(1): 180-190, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35578091

RESUMEN

OBJECTIVES: This study was conducted to evaluate the accuracy of navigation process according to the type of tracking methods and registration markers. The target registration errors (TREs) were measured at seven anatomical landmarks of the mandible. METHODS: Four different experiments were performed to obtain the TREs using two tracking methods, the optical tracker (Polaris) and the electromagnetic (EM) tracker (Aurora), and two types of registration markers, invasive and noninvasive markers. All comparisons of TREs were statistically analyzed using SPSS and Python-based statistical package. RESULTS: The average TRE values obtained from the four experiments were as follows: (1) 0.85 mm (± 0.07) using invasive marker and Aurora, (2) 1.06 mm (± 0.12) using invasive marker and Polaris, (3) 1.43 mm (± 0.15) using noninvasive marker and Aurora, and (4) 1.57 mm (± 0.23) using noninvasive marker and Polaris. Comparisons between all the experimental results revealed statistically significant differences except for the type of tracking system. Although the comparison between the modality of the tracking system showed no significant differences, the EM-based approach consistently demonstrated better performances than the optical type in all comparisons. CONCLUSIONS: This study demonstrates that irrespective of the tracking modality, using invasive marker is a better choice in terms of accuracy. When using noninvasive marker, it is important to consider the increased TREs. In this study, the noninvasive marker caused a maximum increment of TREs of 0.81 mm compared with the invasive marker. Furthermore, using an EM-based tracker with invasive marker may result in the best accuracy for navigation.


Asunto(s)
Cirugía Asistida por Computador , Humanos , Cirugía Asistida por Computador/métodos , Tomografía Computarizada por Rayos X , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Fenómenos Electromagnéticos , Fantasmas de Imagen
15.
Environ Sci Technol ; 46(11): 5824-33, 2012 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-22533634

RESUMEN

The functional gene diversity and structure of microbial communities in a shallow landfill leachate-contaminated aquifer were assessed using a comprehensive functional gene array (GeoChip 3.0). Water samples were obtained from eight wells at the same aquifer depth immediately below a municipal landfill or along the predominant downgradient groundwater flowpath. Functional gene richness and diversity immediately below the landfill and the closest well were considerably lower than those in downgradient wells. Mantel tests and canonical correspondence analysis (CCA) suggested that various geochemical parameters had a significant impact on the subsurface microbial community structure. That is, leachate from the unlined landfill impacted the diversity, composition, structure, and functional potential of groundwater microbial communities as a function of groundwater pH, and concentrations of sulfate, ammonia, and dissolved organic carbon (DOC). Historical geochemical records indicate that all sampled wells chronically received leachate, and the increase in microbial diversity as a function of distance from the landfill is consistent with mitigation of the impact of leachate on the groundwater system by natural attenuation mechanisms.


Asunto(s)
Bacterias/genética , Genes Bacterianos/genética , Variación Genética , Agua Subterránea/microbiología , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Contaminantes Químicos del Agua/análisis , Contaminación del Agua/análisis , Biodegradación Ambiental , Ciclo del Carbono/genética , Análisis por Conglomerados , Monitoreo del Ambiente , Agua Subterránea/química , Compuestos Orgánicos/análisis , Azufre/metabolismo
16.
J Craniofac Surg ; 23(3): e199-202, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22627432

RESUMEN

Greater palatine nerve block anesthesia (GPNBA) is a local anesthetic procedure used for maxillary and nasal treatment. Investigation of the three-dimensional anatomic location of the greater palatine foramen (GPF) is important for successful local anesthesia. The study aim was to provide standards for anatomic structures in the oral cavity that can be easily referred to in GPNBA. Maxillary computed tomography data were obtained from patients between 8 and 16 years of age whose maxillary incisors and first molars had already erupted (the growth group, n = 103); changes in the maxilla were observed over time in this group. Reference values for GPNBA in adults were measured in 107 patients older than 18 years. Maxillary computed tomography images were reconstructed three-dimensionally. Regression analysis demonstrates that all maxillary measurements in the growth group except for the distance from the posterior nasal spine to the GPF in the coronal plane correlated significantly with age. In adults, the mean perpendicular distance from the interdental alveolar bone between the left and right central incisors (1alvB) to the GPF in the coronal plane was 46.16 mm, and the mean distance from 1alvB to the GPF was 51.05 mm. The mean distance from the maxillary central incisor to the GPF was 57.58 mm. The mean angle between the line from the maxillary central incisor to each GPF and the sagittal plane was 16.49 degrees. The mean perpendicular distance from the anterior nasal spine to the GPF in the coronal plane was 43.49 mm, whereas the mean perpendicular distance from the GPF to the bone plane was 12.67 mm, and the mean perpendicular distance from the GPF to the occlusal plane was 22.13 mm. These measurements can be used to find the height of the GPF. In adults, the measured perpendicular distance from the incisive foramen to the GPF in the coronal plane was 32.04 mm, and the perpendicular distance from the median of the line that connects both of the contact points between the maxillary tuberosity and the pterygoid plate to the GPF in the coronal plane was 5.23 mm. Three-dimensional reference values relative to the anatomic structures in the oral cavity may increase the success rate of GPNBA and reduce complications. Although the maxillary growth pattern was analyzed, a limitation of this study is that maxillary anatomic measurements were not analyzed with regard to race or ethnicity.


Asunto(s)
Anestesia Local/métodos , Imagenología Tridimensional , Maxilar/anatomía & histología , Bloqueo Nervioso/métodos , Paladar Duro/inervación , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Maxilar/diagnóstico por imagen , Paladar Duro/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador , Valores de Referencia , Análisis de Regresión
17.
J Craniofac Surg ; 23(4): 1071-6, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22777443

RESUMEN

To determine whether three-dimensionally reconstructed images of skulls created by stitching multiple cone beam computed tomographic (CBCT) images are as accurate as single images obtained using multidetector computed tomography (MDCT), 10 skull models were scanned using an optical three-dimensional scanner, MDCT, and CBCT. Cone beam CT images at 3 different levels of the skull were manually superimposed and stitched. The reconstructed CBCT images at each level were aligned and fused using computer software and then compared to the nominal reference image obtained from the optical three-dimensional scanner by determining positional errors. The reconstructed MDCT images were also compared, and the differences in the mean errors for the 3 image types compared with the nominal reference image data were evaluated. There were no significant differences between the MDCT images and the manually merged CBCT images (Wilcoxon signed rank test, P = 0.017). In contrast, there were significant differences between the MDCT images and the software-aligned CBCT images (P = 0.005). Manual stitching of CBCT sectional images at different levels can provide accurate anatomic details of the oral and maxillofacial regions.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Imagenología Tridimensional/métodos , Tomografía Computarizada Multidetector , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Cráneo/diagnóstico por imagen , Humanos , Modelos Anatómicos , Reproducibilidad de los Resultados , Estadísticas no Paramétricas
18.
Toxics ; 10(9)2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36136489

RESUMEN

Triclosan (TCS) is a widely used chemical whose effects on human health remains elusive. TCS may play a role in a variety of health issues, including endocrine dysfunction, irregular embryonic development, and immune suppression. It is possible that TCS's penetrative abilities across all body barriers, including the blood-brain barrier, may make bioaccumulation the primary driver of these issues. In addition, chronic overuse of this chemical in everyday life may further contribute to the already increasing problem of antibiotic resistance. TCS research has steadily increased since its transition from medical to commercial use over the last 50 years. However, there are some clear gaps in the depth of this research as the safety of this agent is not fully agreed upon. The Food and Drug Administration recently issued regulatory rules regarding TCS in some commercial products; however, it is still found in a variety of goods marketed as "antimicrobial" or "antibacterial". The purpose of this bibliometric study is to analyze research trends in this field and determine the amount of global attention TCS has received as to its relevancy in human health. Documenting and determining research concentration trends related to this field may outline where additional research is most necessary, as well as demonstrate the most valuable research produced and its relation to the advancement of our understanding of TCS. We found there to be a shift in research from TCS and its role in medical environments, to research based on the indirect effects of TCS through environmental contaminations, such as the propagation of antibiotic resistance. This shift was coupled with an increase in global research related to this field and identified China as a significant contributor. Although TCS has received notice, the simple fact of its continued use in so many common products, as well as the unclear understanding of its direct health impacts, reinforces the need for additional and more conclusive research before it has possible irreversible effects on our environment and health.

19.
Imaging Sci Dent ; 52(2): 231-238, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35799964

RESUMEN

Intraosseous xanthoma of the mandible is a rare benign disorder. A 17-year-old male patient presented with a suspected abscess in the right mandibular third molar, detected on a panoramic radiograph. The patient had no history of systemic or lipid-related metabolic diseases and complained of no specific symptoms or pain. A radiographic examination revealed a heterogeneous radiolucency extending from the apical to the distal aspect of the right mandibular third molar tooth germ. The lesion measured 9×16×24 mm (antero-posterior×mediolateral×supero-inferior) and showed a relatively well-defined, multilocular, foamy appearance with hyperostotic borders spreading to the inferior alveolar nerve canal. After excisional biopsy, a diagnosis of central xanthoma was made. The lesion recurred, and intraoral vertical ramus osteotomy was done near the lesion. For the treatment of xanthoma of the mandible, extensive and delicate surgical treatment under general anesthesia should be considered.

20.
Turk J Orthod ; 35(1): 46-54, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35370134

RESUMEN

Traumatic tooth avulsion can lead to ankylosis, which may interfere with growth of the alveolar bone in a growing patient. The resulting difference in alveolar bone height and position can lead to esthetic problems such as open bite. A growing 13-year-old female patient presented skeletal Class III malocclusion with bone ankylosis of a maxillary anterior tooth. Even after 2 years of orthopedic and orthodontic treatment, little improvement was achieved regarding the positions of the anterior maxillary teeth, or the vertical position of the maxillary right central incisor. Therefore, surgical treatment by single-tooth osteotomy (STO) and corticotomy for the anterior ankylosed tooth were considered and performed using a CAD/CAM surgical guide, based on presurgical computer-based simulation surgery. Orthodontic and orthopedic treatments were completed at 10 months after surgery. The patient showed a favorable course of healing, with no mobility issues or gingival recession 3 years after single-tooth osteotomy and corticotomy surgeries. A favorable outcome was finally achieved by applying orthopedic treatment combined with STO and corticotomy for the anterior ankylosed tooth. Orthodontic treatment with minimally surgical method is recommended in an adolescent patient with skeletal Class III malocclusion and anterior open bite.

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