Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
J Helminthol ; 96: e90, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36573372

RESUMO

Limited studies provide direct evidence of Clonorchis sinensis adults in the early stage of gallbladder stone formation. Our current research systematically studied 33 gallbladder stones resembling adult worms and shed light on the definite connection of C. sinensis infection with concomitant cholelithiasis. A total of 33 gallbladder stones resembling adult C. sinensis worms were systematically analysed. Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray energy spectrometry were used to analyse the composition and microstructure. Meanwhile, a histopathological examination of the stone was carried out. The 33 gallbladder stones resembling adult C. sinensis worms included nine calcium carbonate (CaCO3) stones, 12 bilirubinate stones and 12 mixed stones. Clonorchis sinensis eggs were found in 30 cases, including all CaCO3 and mixed stones. Parasite tissues were detected in 12 cases, which were mainly CaCO3 stones or bilirubinate-CaCO3 mixed stones. The outer layer of stones was wrapped with 12.88% calcium salt, as revealed by X-ray energy spectrometry, while surprisingly, many C. sinensis eggs were found in the inner part of these stones. Based on our current findings, we concluded that calcification and packaging occurred after C. sinensis adult entrance into the gallbladder, subsequently leading to the early formation of CaCO3 or bilirubinate-CaCO3 mixed gallbladder stones. This discovery highlights definite evidence for C. sinensis infection causing gallbladder stones.


Assuntos
Clonorchis sinensis , Cálculos Biliares , Animais , Cálculos Biliares/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
2.
Int Endod J ; 52(6): 887-898, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30661246

RESUMO

AIM: To investigate simultaneously the effect of voxel size and fracture width on the accuracy of detecting vertical root fractures (VRFs) in non-root filled teeth when using cone beam computed tomography. METHODOLOGY: Fifty-one of 161 extracted human permanent teeth (16 anterior teeth, 132 premolars and 13 mandibular molars) were selected randomly for VRF induction with two fracture widths. All teeth were scanned with four CBCT units at different voxel sizes provided by the units. Three observers classified the presence or absence of VRF using a 5-point scale. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and area under the ROC curve (AUC) were calculated. AUCs amongst voxel sizes and between the fracture widths were compared using the Z test. Intra- and inter-observer agreement was assessed using weighted Cohen kappa. RESULTS: For the NewTom VGi and ProMax 3D Mid CBCT unit, no significant differences were found amongst voxel sizes for the AUCs, irrespective of the fracture width (P > 0.05). There were significant differences between images scanned with voxel size 250 and 160 µm (P = 0.02), and images scanned with voxel size 250 and 80 µm for AUCs in the narrow VRF group for the 3D Accuitomo 170 unit (P = 0.03). For i-CAT FLX, significant differences were found between the voxel protocols of 300 µm and of the other three voxel sizes for AUC, sensitivity and NPV (P < 0.05). Significant differences between the wide and the narrow VRF groups for AUCs were found for 3D Accuitomo 170 (P = 0.01) and ProMax 3D Mid (P < 0.01). CONCLUSIONS: Cone beam computed tomography was accurate for detecting VRF in non-root filled teeth. Fracture width had an effect on the detection of VRF. The effect of the voxel size on the detection of VRF depended on the CBCT unit used.


Assuntos
Fraturas dos Dentes , Dente Pré-Molar , Tomografia Computadorizada de Feixe Cônico , Humanos , Dente Molar , Sensibilidade e Especificidade , Raiz Dentária
3.
Int Endod J ; 49(7): 646-54, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26102215

RESUMO

The aim of this review was to evaluate whether CBCT is reliable for the detection of root fractures in teeth without root fillings, and whether the voxel size has an impact on diagnostic accuracy. The studies published in PubMed, Web of Science, ScienceDirect, Cochrane Library, Embase, Scopus, CNKI and Wanfang up to May 2014 were the data source. Studies on nonroot filled teeth with the i-CAT (n = 8) and 3D Accuitomo CBCT (n = 5) units were eventually selected. In the studies on i-CAT, the pooled sensitivity was 0.83 and the pooled specificity was 0.91; in the 3D Accuitomo studies, the pooled sensitivity was 0.95 and pooled specificity was 0.96. The i-CAT group comprised 5 voxel size subgroups and the 3D Accuitomo group contained 2 subgroups. For the i-CAT group, there was a significant difference amongst the five subgroups (0.125, 0.2, 0.25, 0.3 and 0.4 mm; P = 0.000). Pairwise comparison revealed that 0.125 mm voxel subgroup was significantly different from those of 0.2, 0.25 and 0.3 mm voxel subgroups, but not from the 0.4 mm voxel subgroup. There were no significant differences amongst any other two subgroups (by α' = 0.005). No significant difference was found between 0.08 mm and 0.125 mm voxel subgroups (P = 0.320) for the 3D Accuitomo group. The present review confirms the detection accuracy of root fractures in CBCT images, but does not support the concept that voxel size may play a role in improving the detection accuracy of root fractures in nonroot filled teeth.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Fraturas dos Dentes/diagnóstico por imagem , Raiz Dentária/lesões , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fraturas dos Dentes/diagnóstico , Raiz Dentária/diagnóstico por imagem
4.
Int J Hyperthermia ; 24(4): 337-45, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18465418

RESUMO

In magnetic nanoparticle hyperthermia for cancer treatment, controlling the heat distribution and temperature elevations is an immense challenge in clinical applications. In this study we evaluate magnetic nanofluid transport and heat distribution induced by commercially available magnetic nanoparticles injected into the extracellular space of biological tissue using agarose gel with porous structures similar to human tissue. The nanofluid distribution in the gel is examined via digital images of the nanofluid spreading in the gel. A radio-frequency electromagnetic field is applied to the gel following the nanofluid injection and the initial rates of temperature rise at various locations are measured to obtain the specific absorption rate (SAR) distribution. By adjusting the gel concentration and injection flow rate, the results have demonstrated that a relatively low injection rate leads to a spherically shaped nanofluid distribution in the gels which is desirable for controlling temperature elevations. The SAR distribution shows that the nanoparticle distribution in the gel is not uniform with a high concentration of the nanoparticles close to the injection site. We believe that the experimental study is the first step towards providing guidance for designing better treatment protocol for future clinical applications.


Assuntos
Magnetismo , Nanopartículas , Neoplasias/terapia , Humanos , Sefarose
6.
J Oral Pathol Med ; 24(9): 407-12, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8537914

RESUMO

Growth characteristics and lysyl oxidase activity of fibroblasts derived from human normal mucosa (NM) and oral submucous fibrosis (OSF) associated with betel nut chewing were compared in cell cultures. The growth rates of cultured cells were identified by plating 5 x 10(5) cells/35 mm culture dish (Day 0) and every 24 hours cell proliferation was determined by quantifying the cell number (using a hemocytometer). The third to seventh passages were used. A medium without serum but supplemented with 5 mg/ml bovine serum albumin was substituted for the original medium at the subconfluent period and cultured for an additional 24 h. The medium was collected and used for assays of protein content and lysyl oxidase activity. Lysyl oxidase activity was assayed with [4,5-3H]--lysine labelled purified chick--embryo aorta elastin substrate. After incubation for 10 h at 37 degrees C, the enzyme activity was measured from 3HHO (tritiated water) separated by ultrafiltration using Amicon C-10 micro-concentrators. The results showed the mean doubling time of OSF fibroblasts was 3.2 days and of NM fibroblasts was 3.6 days. NM fibroblasts became confluent at day 6 as determined by cell number, while OSF fibroblasts were confluent by Day 5. Furthermore, the immunoenzymatic assay for BrdUrd incorporation revealed that OSF fibroblasts proliferate significantly faster than NM fibroblasts under standard culture conditions. Both total protein content (10.84 +/- 1.15 mg/ml) and lysyl oxidase activity (3558.6 +/- 345.5 cpm/10(6) cell) in OSF fibroblasts were greater than in NM fibroblasts (6.35 +/- 0.96 mg/ml and 2436.0 +/- 352.6 cpm/10(6) cell). The results of this study provide evidence that fibroblasts derived from oral submucous fibrosis (OSF) tissue and normal mucosa (NM), although similar in many respects, exhibit specific differences in proliferation rates and lysyl oxidase activity. Moreover, collagen deposition in OSF tissue may, at least in part, be ascribed to increased lysyl oxidase activity.


Assuntos
Areca , Fibroblastos/enzimologia , Fibrose Oral Submucosa/enzimologia , Plantas Medicinais , Proteína-Lisina 6-Oxidase/metabolismo , Adolescente , Adulto , Animais , Bovinos , Contagem de Células , Divisão Celular , Células Cultivadas , Embrião de Galinha , Colágeno/análise , Colágeno/metabolismo , Meios de Cultura Livres de Soro , Elastina/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Mucosa Bucal/enzimologia , Mucosa Bucal/patologia , Fibrose Oral Submucosa/patologia , Proteína-Lisina 6-Oxidase/análise , Proteínas/análise , Proteínas/metabolismo , Soroalbumina Bovina , Taiwan
7.
J Oral Pathol Med ; 28(2): 59-63, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9950251

RESUMO

Oral submucous fibrosis (OSF), a chronic oral mucosal condition commonly found in south Asians, is a disorder characterized by a quantitative as well as a qualitative alteration of collagen deposition within the subepithelial layer of the oral mucosa. Since degradation of collagen by fibroblast phagocytosis is an important pathway for physiological remodelling of soft connective tissues, we have investigated phagocytosis of collagen- and fibronectin-coated latex beads by fibroblast cultures with an in vitro model system. Coated fluorescent latex beads were incubated with human oral mucosa fibroblasts and the fluorescence associated with internalized beads was measured by flow cytometry. Cells from normal tissues that had been incubated with beads for 16 h contained a mean of 75% collagen phagocytic cells and 70% fibronectin phagocytic cells; however, about 15% and 10% of phagocytic cells individually contained more than twice the mean number of beads per cell. In contrast, cells from OSF tissues exhibited a 40% reduction of the proportions of collagen phagocytic cells (mean=35%) and a 48% decrease of the proportions of fibronectin phagocytic cells (mean=22%), none of the cells having a high number of beads as compared to normal fibroblasts. OSF lesions appear to contain fibroblasts with marked deficiencies in collagen and fibronectin phagocytosis. To investigate if inhibition of phagocytosis could be demonstrated in vitro, normal fibroblast cultures were incubated with areca nut alkaloids (arecoline, arecaidine). The cultures had a dose-dependent reduction in the proportions of phagocytic cells. On the other hand, corticosteroid used in the treatment of OSF exhibited a dose-dependent enhancement in the proportion of phagocytic cells. Therefore, our hypothesis for OSF, although oversimplified, is that betel nut alkaloids (arecoline, arecaidine) inhibit fibroblast phagocytosis and this provides a mechanism for the development of OSF. The benefit of a local intralesional injection of corticosteroid is also possibly, at least in part, through an enhancement of fibroblast collagen phagocytosis.


Assuntos
Areca/efeitos adversos , Mucosa Bucal/imunologia , Fibrose Oral Submucosa/etiologia , Fibrose Oral Submucosa/imunologia , Plantas Medicinais , Administração Tópica , Adolescente , Adulto , Anti-Inflamatórios/farmacologia , Arecolina/efeitos adversos , Arecolina/análogos & derivados , Células Cultivadas , Criança , Colágeno/metabolismo , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/imunologia , Fibronectinas/metabolismo , Glucocorticoides , Humanos , Masculino , Mucosa Bucal/citologia , Mucosa Bucal/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Triancinolona/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA