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1.
Ann Sci ; : 1-33, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38562005

RESUMO

The study evaluates Paracelsus's and Paracelsian-Weigelian microcosmogonies, i.e. theories concerning the nature and creation of human beings, especially their biblical underpinnings, and particularly in the light of Luther's and Lutheran anthropological and biblical-exegetical stances. The Lutheran approach to the origin and components of human beings-as seen in Luther's early Magnificat Commentary and the Genesis Commentary of his late career-relied on such magisterial principles as adherence to sola scriptura, literal biblical exegesis, and the hermeneutical standard to 'let scripture interpret scripture,' whereas the Paracelsians, Weigelians, and Pseudo-Weigelians-in such works as Paracelus's Astronomia Magna (1537/38) and the anonymous Astrologia Theologizata (1617)-employed such extra-biblical concepts as 'sidereal bodies,' the 'light of nature,' and a microcosm-macrocosm theory based on an alchemical interpretation of the limus terrae of Genesis 2:7. Seventeenth-century Orthodox Lutherans, including Nikolaus Hunnius and Ehregott Daniel Colberg, castigated the 'heretical' in Paracelsus and the Astrologia Theologizata. The study also addresses the authorship of several texts entitled Astrologia Theologizata and speculates on reasons for the tracts' deviations from Paracelsus's views. The case study of Paracelsian-Weigelian microcosmogonies underscores the centuries-long staying power of some of Paracelsus's core theological concepts, which were both seconded by votaries and vituperatively criticized by opponents.

2.
J Forensic Sci ; 69(3): 993-1001, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38402545

RESUMO

Latent fingerprints on plastic substrates can be visualized by using sequential treatments to enhance the contrast between the fingerprint residues and underlying substrate; however, the extent to which these processes affect subsequent DNA analysis is mostly unknown. Latent fingerprints deposited on black plastic by one donor were visualized with single-process fingerprint powders (i.e., white powder, bichromatic powder, or bichromatic magnetic powder) or sequential treatments (i.e., laser → reflected ultraviolet imaging system (RUVIS) → CA fuming → RUVIS → Rhodamine 6G, Ardrox, and MBD (RAM) or CA fuming → RAM/laser → bichromatic magnetic powder). Samples were examined after the addition of each treatment. DNA was collected using cotton swabs, extracted, quantified, and amplified. DNA yields, peak heights, number of alleles obtained, and percentage of DNA profiles eligible for CODIS upload were examined. Latent fingerprints processed with the laser and up to three sequential treatments generated DNA profiles with significantly higher peaks heights than those of the untreated samples. Fingerprints processed with the laser and up to two sequential treatments generated DNA profiles with significantly more alleles. All methods beginning with laser enhancement generated more CODIS-eligible profiles. Additional research is needed to determine the extent to which initial laser enhancement impacts the success of downstream DNA profiling results. Although DNA profile development is not guaranteed due to the variable quantities of DNA contained within latent fingerprints, the selection of an appropriate latent fingerprint visualization method could maximize both fingerprint detection and the generation of CODIS-eligible DNA profiles.


Assuntos
Impressões Digitais de DNA , DNA , Dermatoglifia , Humanos , DNA/isolamento & purificação , Polietileno , Lasers , Reação em Cadeia da Polimerase , Pós , Repetições de Microssatélites , Manejo de Espécimes/métodos , Alelos , Rodaminas , Plásticos
3.
Cell Rep ; 41(11): 111818, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36516772

RESUMO

Oncogenic KRas activates mitochondrial fission through Erk-mediated phosphorylation of the mitochondrial fission GTPase Drp1. Drp1 deletion inhibits tumorigenesis of KRas-driven pancreatic cancer, but the role of mitochondrial dynamics in other Ras-driven malignancies is poorly defined. Here we show that in vitro and in vivo growth of KRas-driven lung adenocarcinoma is unaffected by deletion of Drp1 but is inhibited by deletion of Opa1, the GTPase that regulates inner membrane fusion and proper cristae morphology. Mechanistically, Opa1 knockout disrupts cristae morphology and inhibits electron transport chain (ETC) assembly and activity, which inhibits tumor cell proliferation through loss of NAD+ regeneration. Simultaneous inactivation of Drp1 and Opa1 restores cristae morphology, ETC activity, and cell proliferation indicating that mitochondrial fission activity drives ETC dysfunction induced by Opa1 knockout. Our results support a model in which mitochondrial fission events disrupt cristae structure, and tumor cells with hyperactive fission activity require Opa1 activity to maintain ETC function.


Assuntos
Adenocarcinoma de Pulmão , NAD , Humanos , NAD/metabolismo , Mitocôndrias/metabolismo , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Membranas Mitocondriais/metabolismo , Dinâmica Mitocondrial , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Dinaminas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
4.
J Hazard Mater ; 437: 129339, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35709620

RESUMO

This study examines amendment of Pb-contaminated soil with modified bauxite refinery residue (MBRR) to decrease soil Pb mobility and bioaccessibility. Amendment experiments were conducted using four soils contaminated with Pb from various sources, including smelting, shooting-range activities and Pb-based paint waste. Lead L3-edge X-ray absorption spectroscopy (XAS) indicated that Pb speciation in these soils was a mixture of Pb sorbed to Fe (hydr)oxide and clay minerals, along with Pb bound to organic matter. Amendment with MBRR decreased water-soluble Pb and/or Toxicity Characteristic Leachate Procedure (TCLP) Pb concentrations. Lead L3-edge XAS and X-ray diffraction (XRD) indicated that Pb retention by MBRR occurred via sorption to Fe- and Al-(hydr)oxides at low Pb loadings, in addition to formation of hydrocerussite (Pb3(CO3)2(OH)2) at high loadings. Soil amendment with MBRR had relatively little effect on gastric-phase Pb bioaccessibility; as quantified via the Solubility/Bioavailability Research Consortium, SBRC, in vitro assay. In contrast, amendment with MBRR caused substantial decreases in relative intestinal-phase Pb bioaccessibility (Rel-SBRC-I) due to increased Pb sorption by MBRR's Fe- and Al-hydr(oxide) minerals as simulated GI tract conditions shifted from the gastric- to the intestinal-phase. These decreases in Rel-SBRC-I point to the potential efficacy of using amendment with MBRR to decrease soil Pb bioavailability.


Assuntos
Poluentes do Solo , Óxido de Alumínio , Chumbo , Óxidos/química , Solo/química , Poluentes do Solo/metabolismo
5.
Environ Pollut ; 305: 119305, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35430314

RESUMO

Antimony (Sb) is a toxic metalloid that has been listed as a priority pollutant. The environmental impacts of Sb have recently attracted attention, but its phytotoxicity and biological transformation remain poorly understood. In this study, Sb speciation and transformation in plant roots was quantified by Sb K-edge X-ray absorption spectroscopy. In addition, the phytotoxicity of antimonate (SbV) on six plant species was assessed by measuring plant photosynthesis, growth, and phytochelatin production induced by SbV. Linear combination fitting of the Sb K-edge X-ray absorption near-edge structure (XANES) spectra indicated reduction of SbV was limited to ∼5-33% of Sb. The data confirmed that Sb-polygalacturonic acid was the predominant chemical form in all plant species (up to 95%), indicating Sb was primarily bound to the cell walls of plant roots. Shell fitting of Sb K-edge X-ray absorption fine-structure (EXAFS) spectra confirmed Sb-O and Sb-C were the dominant scattering paths. The fitting indicated that SbV was bound to hydroxyl functional groups of cell walls, via development of a local coordination environment analogous to Sb-polygalacturonic acid. This is the first study to demonstrate the key role of plant cell walls in Sb metabolism.


Assuntos
Antimônio , Fitoquelatinas , Antimônio/química , Raízes de Plantas/metabolismo , Espectroscopia por Absorção de Raios X
6.
J Neurosurg ; : 1-13, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35334465

RESUMO

OBJECTIVE: Magnetic resonance imaging at 7T offers improved image spatial and contrast resolution for visualization of small brain nuclei targeted in neuromodulation. However, greater image geometric distortion and a lack of compatible instrumentation preclude implementation. In this report, the authors detail the development of a stereotactic image localizer and accompanying imaging sequences designed to mitigate geometric distortion, enabling accurate image registration and surgical planning of basal ganglia nuclei. METHODS: Magnetization-prepared rapid acquisition with gradient echo (MPRAGE), fast gray matter acquisition T1 inversion recovery (FGATIR), T2-weighted, and T2*-weighted sequences were optimized for 7T in 9 human subjects to visualize basal ganglia nuclei, minimize image distortion, and maximize target contrast-to-noise and signal-to-noise ratios. Extracranial spatial distortions were mapped to develop a skull-contoured image localizer embedded with spherical silicone fiducials for improved MR image registration and target guidance. Surgical plan accuracy testing was initially performed in a custom-developed MRI phantom (n = 5 phantom studies) and finally in a human trial. RESULTS: MPRAGE and T2*-weighted sequences had the best measures among global measures of image quality (3.8/4, p < 0.0001; and 3.7/4, p = 0.0002, respectively). Among basal ganglia nuclei, FGATIR outperformed MPRAGE for globus pallidus externus (GPe) visualization (2.67/4 vs 1.78/4, p = 0.008), and FGATIR, T2-weighted imaging, and T2*-weighted imaging outperformed MPRAGE for substantia nigra visualization (1.44/4 vs 2.56/4, p = 0.04; vs 2.56/4, p = 0.04; vs 2.67/4, p = 0.003). Extracranial distortion was lower in the head's midregion compared with the base and apex ( 1.17-1.33 mm; MPRAGE and FGATIR, p < 0.0001; T2-weighted imaging, p > 0.05; and T2*-weighted imaging, p = 0.013). Fiducial placement on the localizer in low distortion areas improved image registration (fiducial registration error, 0.79-1.19 mm; p < 0.0001) and targeting accuracy (target registration error, 0.60-1.09 mm; p = 0.04). Custom surgical software and the refined image localizer enabled successful surgical planning in a human trial (fiducial registration error = 1.0 mm). CONCLUSIONS: A skull-contoured image localizer that accounts for image distortion is necessary to enable high-accuracy 7T imaging-guided targeting for surgical neuromodulation. These results may enable improved clinical efficacy for the treatment of neurological disease.

7.
J Forensic Sci ; 67(1): 149-160, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34498754

RESUMO

Forensic examiners must determine whether both latent fingerprint development and DNA profiling can be performed on the same area of an evidence item and, if only one is possible, which examination offers the best chance for identification. Latent fingerprints can be enhanced by targeting different components of fingerprint residues with sequential chemical treatments. This study investigated the effects of single-reagent and sequential latent fingerprint development processes on downstream DNA analysis to determine the point at which latent fingerprint development should be stopped to allow for DNA recovery. Latent fingerprints deposited on copy paper by one donor were developed using three sequential processes: 1,8-diazafluoren-9-one (DFO) â†’ ninhydrin â†’ physical developer (PD); 1,2-indanedione-zinc (IND-Zn) â†’ ninhydrin â†’ PD; and IND-Zn â†’ ninhydrin â†’ Oil Red O (ORO) â†’ PD. Samples were examined after the addition of each chemical treatment. DNA was collected with cotton swabs, extracted, quantified, and amplified. DNA yields, peak heights, number of alleles obtained, and percentage of DNA profiles eligible for CODIS upload were examined. DNA profiles were obtained with varying degrees of success, depending on the number and type of treatments used for latent fingerprint development. The treatments that were found to be the least harmful to downstream DNA analysis were IND-Zn and IND-Zn/laser, and the most detrimental treatments were DFO, DFO/laser, and PD. In general, as the number of treatments increase, the opportunities for DNA loss or damage also increase, and it is preferable to use fewer treatments when developing latent fingerprints prior to downstream DNA processing.


Assuntos
Impressões Digitais de DNA , Dermatoglifia , DNA , Indicadores e Reagentes , Ninidrina , Papel
8.
Med J (Ft Sam Houst Tex) ; (PB 8-21-10/11/12): 40-49, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34714921

RESUMO

OBJECTIVE: The objective of this study was to illustrate the efficacy of a novel imaging analysis technology to capture horizontal and vertical dimensional changes following horizontal alveolar ridge augmentation (HRA). METHODS: Cone-beam computed tomography (CBCT) volumes from 65 HRA sites in 57 patients were available for evaluation, employing a three-dimensional analysis software to overlay preoperative and post-augmentation CBCT volumes. Horizontal and vertical alveolar ridge dimensional (HRD/VRD) changes were recorded considering a panel of patient-, site-, and procedure-related explanatory variables. RESULTS: VRD changes ranged from -2.9 to 3.0 mm, more than half anterior sites losing alveolar ridge height. Mean HRD increase at the 3- and 5-mm levels apical to the alveolar crest amounted to 2.3±1.6 and 2.4±1.3 mm, respectively, membrane fixation and non-resorbable membrane use associated with significantly greater gains. CONCLUSIONS: To date, studies reporting dimensional changes following HRA predominantly rely on serial in situ orofacial caliper recordings omitting vertical alterations. The protocol employed in this study allows simultaneous HRD and VRD evaluations and assures baseline and post-augmentation recordings are made at the same alveolar ridge position. Compared with in situ recording, CBCT overlay analysis may achieve a more complete characterization of dimensional changes following HRA.


Assuntos
Aumento do Rebordo Alveolar , Processo Alveolar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Humanos
9.
Cell Mol Life Sci ; 78(8): 3803-3816, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33580834

RESUMO

Many tumors are now understood to be heterogenous cell populations arising from a minority of epithelial-like cancer stem cells (CSCs). CSCs demonstrate distinctive metabolic signatures from the more differentiated surrounding tumor bulk that confer resistance to traditional chemotherapeutic regimens and potential for tumor relapse. Many CSC phenotypes including metabolism, epithelial-to-mesenchymal transition, cellular signaling pathway activity, and others, arise from altered mitochondrial function and turnover, which are regulated by constant cycles of mitochondrial fusion and fission. Further, recycling of mitochondria through mitophagy in CSCs is associated with maintenance of reactive oxygen species levels that dictate gene expression. The protein machinery that drives mitochondrial dynamics is surprisingly simple and may represent attractive new therapeutic avenues to target CSC metabolism and selectively eradicate tumor-generating cells to reduce the risks of metastasis and relapse for a variety of tumor types.


Assuntos
Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Transição Epitelial-Mesenquimal , Humanos , Mitocôndrias/patologia , Mitofagia , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Espécies Reativas de Oxigênio/metabolismo
10.
J Hazard Mater ; 407: 124819, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33341573

RESUMO

The ageing of a contaminant in soil influences the bioavailability and toxicity of environmental pollutants. Yet, despite arsenic (As) being an important terrestrial contaminant, the effect of As ageing on phytotoxicity has received relatively little research. Research to date has reported predominantly short term (< 0.5 years) experiments. Here, we studied the influence of ageing over 0.25 and 5 years on the phytotoxicity of As (as arsenate) on Cucumis sativus L. (cucumber). The study showed that increasing ageing time of As from 0.25 to 5 years increased the EC10 and EC50 values by 4.0 and 1.76 fold, respectively. The dependence of ageing on soil properties was also examined, although only Freundlich sorption parameters were correlated to the ageing factor (r = 0.68, P = 0.028). Soils with high adsorption capacity also showed the greatest change in toxicity over 5 years. In addition, data was compiled from relevant literature to develop a model for As ecotoxicity. The combined model (n = 54) showed no relationship with pH but was correlated to the oxalate extractable iron content and %clay. Arsenate ecotoxicity (EC50, mg/kg) in the multivariate model was related to oxalate iron content, %clay and ageing time. Thus, the results of this study have significant implications for risk assessment of long-term As contaminated soils.


Assuntos
Arsênio , Poluentes do Solo , Adsorção , Arsênio/toxicidade , Disponibilidade Biológica , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
11.
J Hazard Mater ; 403: 123931, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264981

RESUMO

Naturally arsenic (As) enriched agricultural soils represent a significant global human health risk. In this study, As fractionation and mineralogy were investigated in naturally As-enriched agricultural soils and their corresponding sand, silt and clay fractions. Median As increased generally in the order (mg/kg)∶ silt (280) < bulk (314) < sand (323)

12.
Clin Adv Periodontics ; 11(1): 27-32, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32064774

RESUMO

INTRODUCTION: Schneiderian membrane perforation (SMP), which is usually readily manageable, is the most common intraoperative complication of sinus elevation surgery. Some evidence suggests that SMP is associated with increased risk for postoperative complications, including maxillary sinusitis. Antral wall discontinuity (AWD) is an acquired condition that may increase SMP likelihood and lead to larger, less-manageable perforations. CASE PRESENTATION: A generally healthy patient receiving sinus elevation surgery exhibited an AWD in the palatine process of the maxilla. The osseous defect was isolated intraoperatively, and the Schneiderian membrane was sharply dissected from the palatal connective tissue. Favorable augmentation of the maxillary sinus was noted on cone-beam computed tomography (CBCT) assessment at postoperative month 34. CONCLUSIONS: AWD (fusion of the Schneiderian membrane with the periosteum of the maxilla) is a condition identifiable on preoperative CBCT images, which may increase the incidence and severity of SMP during sinus elevation procedures. Careful assessment for integrity of antral osseous walls before surgery is essential. Presence of AWD may obligate modifications to the surgical plan, or in some cases, contraindicate sinus elevation surgery.


Assuntos
Sinusite Maxilar , Levantamento do Assoalho do Seio Maxilar , Tomografia Computadorizada de Feixe Cônico , Humanos , Maxila , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia
13.
Sci Rep ; 10(1): 18941, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33144635

RESUMO

Mitochondria are highly dynamic organelles that can exhibit a wide range of morphologies. Mitochondrial morphology can differ significantly across cell types, reflecting different physiological needs, but can also change rapidly in response to stress or the activation of signaling pathways. Understanding both the cause and consequences of these morphological changes is critical to fully understanding how mitochondrial function contributes to both normal and pathological physiology. However, while robust and quantitative analysis of mitochondrial morphology has become increasingly accessible, there is a need for new tools to generate and analyze large data sets of mitochondrial images in high throughput. The generation of such datasets is critical to fully benefit from rapidly evolving methods in data science, such as neural networks, that have shown tremendous value in extracting novel biological insights and generating new hypotheses. Here we describe a set of three computational tools, Cell Catcher, Mito Catcher and MiA, that we have developed to extract extensive mitochondrial network data on a single-cell level from multi-cell fluorescence images. Cell Catcher automatically separates and isolates individual cells from multi-cell images; Mito Catcher uses the statistical distribution of pixel intensities across the mitochondrial network to detect and remove background noise from the cell and segment the mitochondrial network; MiA uses the binarized mitochondrial network to perform more than 100 mitochondria-level and cell-level morphometric measurements. To validate the utility of this set of tools, we generated a database of morphological features for 630 individual cells that encode 0, 1 or 2 alleles of the mitochondrial fission GTPase Drp1 and demonstrate that these mitochondrial data could be used to predict Drp1 genotype with 87% accuracy. Together, this suite of tools enables the high-throughput and automated collection of detailed and quantitative mitochondrial structural information at a single-cell level. Furthermore, the data generated with these tools, when combined with advanced data science approaches, can be used to generate novel biological insights.


Assuntos
Mitocôndrias/metabolismo , Software , Animais , Biologia Computacional , Humanos , Processamento de Imagem Assistida por Computador , Mitocôndrias/genética , Dinâmica Mitocondrial/genética , Dinâmica Mitocondrial/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
14.
Nanoscale ; 12(4): 2434-2438, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31746902

RESUMO

We present an in situ nanobeam grazing-incidence X-ray diffraction (nanoGIXD) study of real-sized organic field effect transistors (OFET) under applied voltage. The nano-sized beam allows for spatially resolved monitoring of the structural behavior across the poly(3-hexylthiophene) (P3HT) polymer channel and the interfacial regions of the source and drain gold electrodes before and after the operation cycle. We observe major alterations of the gold contacts, in particular diffusion of Au atoms into the polymer channel and a local reorientation of the recrystallized Au nanocrystallites quantified by Hermans' orientation factors. Therefore, the initially sharp electrode-polymer interfaces are significantly modified as a result of device operation. Our findings demonstrate that nanoGIXD has a high potential to probe functionality and reliability of working organic devices.

15.
Clin Adv Periodontics ; 9(4): 177-184, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31496044

RESUMO

INTRODUCTION: Postoperative discomfort is a documented complication of the epithelialized palatal graft (EPG) procedure, and the expectation of an unpleasant patient experience may cause some practitioners to avoid EPG altogether. However, EPG affords distinct advantages in a variety of clinical situations, and the postoperative discomfort associated with the procedure can be minimized. CASE SERIES: Three generally and periodontally healthy patients with gingival recession defects and minimal zones of attached gingiva received mandibular anterior EPG procedures. In all cases, collagen membranes were trimmed to fit the palatal donor sites and sutured in place. Two patients reported minimal donor site discomfort at any time point. One patient with large bilateral donor sites reported moderate palatal discomfort limited to the first postoperative week. All patients reported overall positive treatment experiences. CONCLUSIONS: Placement of a resorbable collagen membrane at large EPG harvest sites appears to limit topical irritation of the wound and may substantially improve patient comfort postoperatively. Combining local and systemic measures to minimize patient discomfort may render EPG procedures very tolerable for patients. Controlled clinical trials comparing patient-centered outcomes following EPG harvest with and without collagen membrane placement appear warranted.


Assuntos
Gengiva/transplante , Retração Gengival , Palato , Conforto do Paciente , Colágeno , Humanos , Palato/cirurgia , Doadores de Tecidos
16.
Curr Protoc Protein Sci ; 97(1): e88, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31517450

RESUMO

Heterologous expression of the G protein-coupled estrogen receptor (GPER) comes with a suite of challenges intrinsic to membrane proteins. This receptor's low expression levels and tendency to form insoluble aggregates in Escherichia coli and yeast make it a difficult receptor-target to study. In this unit, we detail steps to produce monomeric GPER using a precipitation-based cell-free system. We provide information on the DNA construct for expression, the pipetting scheme for the reaction supplements to generate a master mix, and the cell-free reaction setup. In the last portion of this unit, we outline steps for solubilization and purification, and we provide a viable method for qualitatively observing functionality by liquid chromatography-mass spectrometry detection. © 2019 by John Wiley & Sons, Inc.


Assuntos
Escherichia coli/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/isolamento & purificação , Sistema Livre de Células/metabolismo , Cromatografia Líquida de Alta Pressão , DNA Complementar/metabolismo , Expressão Gênica , Humanos , Espectrometria de Massas em Tandem
17.
Clin Adv Periodontics ; 9(3): 125-134, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31490043

RESUMO

INTRODUCTION: Whether or not laser use provides any meaningful benefit at immediate implant and ridge preservation sites remains an open question in periodontics. However, various lasers have been used in conjunction with tooth extraction and immediate implant placement. Evidence supporting adjunctive laser irradiation at immediate implant and ridge preservation sites is mostly limited to preclinical studies and a small number of case reports. CASE SERIES: Adjunctive neodymium‒doped: yttrium, aluminum, garnet (Nd:YAG) laser irradiation was used at six immediate implant sites and five ridge preservation sites. Three immediate implants were in maxillary incisor positions and three were in premolar positions, two maxillary and one mandibular. All cases exhibited favorable healing and satisfactory clinical outcomes. CONCLUSIONS: Nd:YAG laser energy application with 650-µs pulse duration consistently supported rapid clot formation and graft containment at immediate implant and ridge preservation sites. Histologic analyses and controlled clinical trials comparing ridge preservation and immediate implant procedures with and without laser use are needed. Because cellular responses and clinical outcomes may be exquisitely sensitive to irradiation parameters, studies should report materials and methods in detail.


Assuntos
Implantes Dentários , Terapia a Laser , Extração Dentária , Humanos , Lasers de Estado Sólido , Maxila , Extração Dentária/métodos , Alvéolo Dental
18.
J Periodontol ; 90(6): 595-607, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30578550

RESUMO

BACKGROUND: Crestal bone thickness is a critical determinant of peri-implant tissue stability. This retrospective observational study sought to quantify the buccal bone thickness achieved adjacent to virtual dental implants following guided bone regeneration (GBR) surgery and evaluate the influence of patient- and procedure-related variables on buccal bone thickness. METHODS: Cone-beam computed tomography (CBCT) images acquired from patients who had undergone GBR surgery between July 1, 2012, and November 7, 2016, were used for this analysis. In all cases, the GBR procedure involved a dense polytetrafluoroethylene (dPTFE) barrier membrane and a mineralized cortical particulate freeze-dried bone allograft (FDBA). Eighty-four virtual dental implants were placed at planned locations using CBCT images from 84 patients, and the adjacent buccal bone thickness was measured at each site. The effects of sex, age, estimated baseline ridge width, number of missing teeth in site, site type (tooth-bounded versus terminal position in arch), dental arch (mandibular or maxillary), arch location (anterior or posterior), smoking status, titanium reinforcement in the membrane, membrane fixation, and tenting screw use were assessed. RESULTS: The mean post-GBR buccal bone thickness adjacent to virtual dental implants was 2.24 ± 1.01 mm. Fifty-nine of 84 virtual implants (70%) exhibited buccal bone thickness > 1.9 mm. GBR sites using membrane fixation produced significantly greater virtual implant buccal bone thickness than those without membrane fixation (2.31 ± 0.96 versus 1.15 ± 1.25 mm, P = 0.012). Virtual implant buccal bone thickness also exhibited moderate correlation with estimated initial ridge width (r = 0.43, P < 0.0001). The alveolar ridge at 81 virtual implant sites (96%) was classified as good or satisfactory, meaning dental implants were actually placed at these sites, with or without additional grafting at implant placement. CONCLUSIONS: Observations in this study suggest GBR procedures using dPTFE membranes and FDBA result in favorable ridge dimensions for dental implant placement in most cases. However, additional augmentation at implant surgery may be necessary at ≈ 30% of sites, if buccal bone thickness > 1.9 mm is intended.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Regeneração Óssea , Transplante Ósseo , Implantação Dentária Endóssea , Humanos , Membranas Artificiais , Estudos Retrospectivos
19.
Ecotoxicol Environ Saf ; 148: 738-746, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29179146

RESUMO

Arsenic (As) and copper (Cu) are co-contaminants in the environment but little is known about their ecological impact as mixtures in soil. In this study, we investigated the combined As-Cu interactions on toxicity and uptake as binary mixtures in 5 contrasting soils. The study included solubility, contaminant uptake and toxicity in cucumber (Cucumis sativus L.) as a model plant species. Soils were spiked individually and as a mixtures at 10 different As levels (2, 4, 8 up to 1024mgkg-1). Copper was added with As at two effective concentration levels (EC10Cu and EC50Cu). Arsenic uptake was significantly reduced in the presence of Cu and a higher effect was demonstrated with increasing pore-water pH. Copper accumulation was not significantly influenced by As. An additive response on plant growth was predominant overall when expressed from pore-water parameters with root mean square errors of 12.6 and 13.2 for EC10Cu and EC50Cu treatments, respectively.


Assuntos
Arsênio/toxicidade , Cobre/toxicidade , Cucumis sativus/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Arsênio/metabolismo , Disponibilidade Biológica , Cobre/metabolismo , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/metabolismo , Sinergismo Farmacológico , Poluentes do Solo/metabolismo , Solubilidade , Água/química
20.
Chemosphere ; 187: 357-367, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28863290

RESUMO

Arsenic (As) and zinc (Zn) are common co-contaminants in mining impacted soils. Their interaction on solubility and toxicity when present concurrently is not well understood in natural systems. The aim of this study was to observe their interaction in solubility (soil-solution), bioaccumulation (shoot uptake) and toxicity to cucumber (Cucumis sativa L) conducting 4 weeks pot study in 5 different soils spiked with As (0, 2, 4, 8 to 1024 mg kg-1) individually and with Zn at two phytotoxic doses. The As pore-water concentration was significantly reduced (df = 289, Adjusted R2 = 0.84, p < 0.01) in the presence of Zn in the whole dataset, whereas Zn and Zn2+ activity in pore-water was reduced significantly only in the two alkaline soils. This outcome may be due to adsorption/surface precipitation or tertiary bridging complexation. No homogenous precipitation of zinc arsenate could be established using electron microscopy, XRD or even equilibrium calculations. For bioaccumulation phase, no significant effect of Zn on As uptake was observed except acidic MG soil whereas, Zn uptake was significantly reduced (p < 0.05) by As in whole dataset. However, an additive response was observed mostly except acidic MG soil. The synergistic response (more than additive) was predominant in this soil for a wide range of inhibition concentration (0-80%) at both Zn EC10 and EC50 levels. Since additive response is mostly considered in risk assessment for mixtures, precautions should be implemented for assessment of toxicity for As-Zn mixture in acidic soil due to their synergistic response in some soils.


Assuntos
Arsênio/análise , Cucumis sativus/efeitos dos fármacos , Poluentes do Solo/análise , Solo/química , Zinco/análise , Adsorção , Arsênio/farmacocinética , Arsênio/toxicidade , Cucumis sativus/metabolismo , Interações Medicamentosas , Mineração , Medição de Risco , Poluentes do Solo/farmacocinética , Poluentes do Solo/toxicidade , Solubilidade/efeitos dos fármacos , Água/química , Zinco/farmacocinética , Zinco/toxicidade
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