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1.
J Texture Stud ; 54(6): 835-844, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37340614

RESUMO

During videofluoroscopic swallowing study (VFSS), barium sulfate (BaSO4 ) is commonly added into food samples as a radiopaque contrast media for bolus visualization and examination. Accordingly, the consistency and flow behavior of barium stimuli can differ significantly from their non-barium counterparts. Such differences may have a subsequent impact on the validity of VFSS. Therefore, in this study, effects of barium sulfate on the shear and extensional rheological properties and IDDSI (International Dysphagia Diet Standardization Initiative) flow consistency of liquids prepared using various commercial thickening powders were investigated. Results showed that all barium stimuli exhibited shear thinning behavior but with significantly higher shear viscosity compared to the non-barium counterparts. A shift factor of viscosity at shear rate 50 s-1 with values in range of 1.21-1.73 could be used to describe the increase in the viscosity for samples thickened with gum-based thickeners. However, the change in the viscosity was not invariant for the stimuli prepared starch-based thickener. The addition of BaSO4 had a negative impact on extensional properties of samples by demonstrating a faster filament rupture. The extent of impact on the decrease in filament breakup time was more pronounced in xanthan > guar gum ≈ tara gum-based thickeners. Based on the IDDSI flow test, no significant effect of BaSO4 was found on the gum-based thickeners, whereas there was a marked effect in the starch-based sample. These results can be used beneficially to assist clinicians in the dysphagia diagnosis for matching rheological properties of the barium stimuli to enhance effectiveness dysphagia interventions.


Assuntos
Transtornos de Deglutição , Humanos , Deglutição , Sulfato de Bário/farmacologia , Bário/farmacologia , Pós , Aditivos Alimentares/farmacologia , Amido
2.
Acta Biomater ; 164: 577-587, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37019167

RESUMO

Cytotoxicity and cellular uptake of spherical barium sulphate microparticles (diameter 1 µm) were studied with three different cell lines, i.e. THP-1 cells (monocytes; model for a phagocytosing cell line), HeLa cells (epithelial cells; model for a non-phagocytosing cell line), and human mesenchymal stem cells (hMSCs; model for non-phagocytosing primary cells). Barium sulphate is a chemically and biologically inert solid which allows to distinguish two different processes, e.g. the particle uptake and potential adverse biological reactions. Barium sulphate microparticles were surface-coated by carboxymethylcellulose (CMC) which gave the particles a negative charge. Fluorescence was added by conjugating 6-aminofluorescein to CMC. The cytotoxicity of these microparticles was studied by the MTT test and a live/dead assay. The uptake was visualized by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The particle uptake mechanism was quantified by flow cytometry with different endocytosis inhibitors in THP-1 and HeLa cells. The microparticles were easily taken up by all cell types, mostly by phagocytosis and micropinocytosis, within a few hours. STATEMENT OF SIGNIFICANCE: The interaction of particles and cells is of primary importance in nanomedicine, drug delivery, and nanotoxicology. It is commonly assumed that cells take up only nanoparticles unless they are able to phagocytosis. Here, we demonstrate with chemically and biologically inert microparticles of barium sulphate that even non-phagocytosing cells like HeLa and hMSCs take up microparticles to a considerable degree. This has considerable implication in biomaterials science, e.g. in case of abrasive debris and particulate degradation products from implants like endoprostheses.


Assuntos
Sulfato de Bário , Fagocitose , Humanos , Células HeLa , Sulfato de Bário/farmacologia , Sulfato de Bário/metabolismo , Endocitose , Macrófagos/metabolismo , Tamanho da Partícula
3.
PLoS One ; 17(2): e0263061, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35192627

RESUMO

Cold-water coral (CWC) reefs are numerous and widespread along the Norwegian continental shelf where oil and gas industry operate. Uncertainties exist regarding their impacts from operational discharges to drilling. Effect thresholds obtained from near-realistic exposure of suspended particle concentrations for use in coral risk modeling are particularly needed. Here, nubbins of Desmophyllum pertusum (Lophelia pertusa) were exposed shortly (5 days, 4h repeated pulses) to suspended particles (bentonite BE; barite BA, and drill cuttings DC) in the range of ~ 4 to ~ 60 mg.l-1 (actual concentration). Physiological responses (respiration rate, growth rate, mucus-related particulate organic carbon OC and particulate organic nitrogen ON) and polyp mortality were then measured 2 and 6 weeks post-exposure to assess long-term effects. Respiration and growth rates were not significantly different in any of the treatments tested compared to control. OC production was not affected in any treatment, but a significant increase of OC:ON in mucus produced by BE-exposed (23 and 48 mg.l-1) corals was revealed 2 weeks after exposure. Polyp mortality increased significantly at the two highest DC doses (19 and 49 mg.l-1) 2 and 6 weeks post-exposure but no significant difference was observed in any of the other treatments compared to the control. These findings are adding new knowledge on coral resilience to short realistic exposure of suspended drill particles and indicate overall a risk for long-term effects at a threshold of ~20 mg.l-1.


Assuntos
Adaptação Fisiológica , Antozoários/efeitos dos fármacos , Sulfato de Bário/farmacologia , Bentonita/farmacologia , Material Particulado/farmacologia , Taxa Respiratória/efeitos dos fármacos , Animais , Antozoários/crescimento & desenvolvimento , Carbono/química , Carbono/metabolismo , Recifes de Corais , Indústrias Extrativas e de Processamento/métodos , Humanos , Longevidade/efeitos dos fármacos , Nitrogênio/química , Nitrogênio/metabolismo , Noruega , Taxa Respiratória/fisiologia , Água/química
4.
Sci Rep ; 9(1): 8163, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160608

RESUMO

We have shown that barium [from BaSO4 nanoparticles (NPs)] was cleared from the lungs faster than other poorly soluble NPs and translocated mostly to bone. We now studied barium biokinetics in rats during Study 1: two-year inhalation exposure to 50 mg/m3 BaSO4 NP aerosols, and Study 2: single intratracheal (IT) instillation of increasing doses of BaSO4 NPs or BaCl2. Study 1 showed that lung barium content measured by inductively coupled plasma mass spectrometry increased during 360 days of BaSO4 NP aerosol exposures. An equilibrium was established from that time until 2 years. Barium concentrations in BaSO4-exposed animals were in the order (lungs > lymph nodes > hard bone > bone marrow > liver). In Study 2, there was an increase in lung barium post-IT instillation of BaSO4 NPs while barium from BaCl2 was mostly cleared by day 28. Transmission electron microscopy showed intact BaSO4 NPs in alveolar macrophages and type II epithelial cells, and in tracheobronchial lymph nodes. Using stimulated Raman scattering microscopy, specific BaSO4 Raman spectra were detected in BaSO4 NP-instilled lungs and not in other organs. Thus, we posit that barium from BaSO4 NPs translocates from the lungs mainly after dissolution. Barium ions are then incorporated mostly into the bone and other organs.


Assuntos
Sulfato de Bário/farmacologia , Pulmão/efeitos dos fármacos , Nanopartículas/química , Distribuição Tecidual/efeitos dos fármacos , Aerossóis/química , Aerossóis/farmacologia , Animais , Sulfato de Bário/química , Exposição por Inalação , Macrófagos Alveolares/efeitos dos fármacos , Ratos
5.
Contrast Media Mol Imaging ; 2019: 5215923, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31110469

RESUMO

Purpose: Barium sulfate and lead oxide are commonly used for angiographic studies, but there is no report on the comparison of two contrast agents in angiography of cervical spinal cord. This study was aimed to compare the microvascular architecture of cervical spinal cord in rats after angiography with the barium sulfate agent to the lead oxide agent. Methods: Twelve adult Sprague-Dawley rats were randomly divided into the barium sulfate group (n=6) and the lead oxide group (n=6). Each rat was perfused under the same protocol using either two contrast agents. The angiography was evaluated with the vascular number at different ranks. The cervical spinal cord samples were scanned using micro-CT with low resolution and high resolution. The microvascular parameters, including ratio of vascular volume to tissue volume (VV/TV), vascular number (V.N), diameter (V.Dm), separation (V.Sp), connectivity density (Conn.D), structure model index (SMI), percentage, and volume of vessels at different diameters were measured. Results: The perfusion was better in the barium sulfate group, with more blood vessel trees of rank II and III visible compared to the lead oxide group. Low-resolution micro-CT analysis showed no difference in microvascular parameters except SMI between the two groups. High-resolution micro-CT analysis results showed that V.N and Conn.D of barium sulfate group were 60% and 290% more than those of the lead oxide group; however, V.Sp was 41% less than the lead oxide group. The percentage of vessels with diameter of 10 µm and 20 µm, and the volume of vessels with diameter of less than 100 µm was higher in the barium sulfate group than in the lead oxide group. The SMI index in the barium sulfate group was higher than that in the lead oxide group at both low resolution and high resolution. Conclusions: Compared with lead oxide, barium sulfate is more suitable for perfusion of cervical spinal cord microvessels, and cheap and nontoxic with high resolution.


Assuntos
Sulfato de Bário/farmacologia , Medula Cervical/diagnóstico por imagem , Meios de Contraste/farmacologia , Chumbo/farmacologia , Óxidos/farmacologia , Animais , Sulfato de Bário/química , Medula Cervical/patologia , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/química , Humanos , Imageamento Tridimensional/métodos , Chumbo/química , Óxidos/química , Ratos , Ratos Sprague-Dawley , Medula Espinal/diagnóstico por imagem , Microtomografia por Raio-X/métodos
6.
J Endod ; 44(9): 1376-1380, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30078570

RESUMO

INTRODUCTION: We evaluated the radiopacity and antibacterial properties of various concentrations of double antibiotic paste (DAP) containing barium sulfate (BaSO4) or zirconium oxide (ZrO2) radiopaque agents. METHODS: The radiopacity of 1, 10, and 25 mg/mL DAP containing 30% (w/v) BaSO4 or ZrO2, DAP-free radiopaque pastes, and commercially available radiopaque calcium hydroxide (Ca[OH]2) were evaluated according to ISO 6876/2001 with slight modifications (n = 6 per group). Dentin samples (n = 70) infected anaerobically for 3 weeks with bacterial biofilms obtained from a root canal of an immature tooth with pulpal necrosis were treated with similar experimental pastes or received no treatment (n = 7). After 1 week, the pastes were rinsed off, and biofilm disruption assays were conducted. To show the residual antibacterial effects, sterile dentin samples (n = 70) were pretreated for 1 week with the same pastes (n = 7). The pastes were rinsed off, and the samples were immersed in phosphate-buffered saline for 24 hours and infected anaerobically with the same bacterial biofilm mentioned earlier for 3 weeks before conducting biofilm disruption assays. Sterile dentin blocks were used in both antibacterial analyses as negative control groups (n = 7). Wilcoxon rank sum tests were used for statistical analyses. RESULTS: No tested concentrations of BaSO4 DAP or ZrO2 DAP showed significant differences from Ca(OH)2 in radiopacity. However, all tested concentrations of BaSO4 DAP, ZrO2 DAP, and Ca(OH)2 exhibited significant direct antibacterial effects. ZrO2 DAP at 1 mg/mL and Ca(OH)2 did not show significant residual antibacterial effects. CONCLUSIONS: BaSO4 DAP at 1 mg/mL provided significantly superior residual antibacterial effects and comparable radiopacity with the commercially available Ca(OH)2.


Assuntos
Antibacterianos/farmacologia , Sulfato de Bário/farmacologia , Biofilmes/efeitos dos fármacos , Ciprofloxacina/farmacologia , Necrose da Polpa Dentária/microbiologia , Polpa Dentária/microbiologia , Metronidazol/farmacologia , Endodontia Regenerativa , Irrigantes do Canal Radicular/farmacologia , Zircônio/farmacologia , Formas de Dosagem , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana , Enterococcus faecalis/fisiologia , Humanos
7.
J Contemp Dent Pract ; 19(6): 680-683, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29959296

RESUMO

AIM: The study aimed to evaluate the efficacy of root canal sealer's antimicrobial activity against Enterococcus faecalis. MATERIALS AND METHODS: Root canal sealers with the brands Endoflas FS, AH Plus, and Tubli-Seal EWT were selected. Enterococcus faecalis organisms' zone of inhibition was measured. Tukey post hoc tests and one-way analysis of variance (ANOVA) were used to compare the data among study groups and within its group. The data were said to be statistically significant with an established p-value less than 0.05. RESULTS: The maximum zone of inhibition (23.20 ± 1.202 mm) was shown by Endoflas FS sealer; AH Plus and Tubli-Seal showed the inhibition zone of (18.42 ± 1.023) and (16.88 ± 0.962) respectively, following Endoflas FS. The ANOVA test showed p < 0.0001, which is highly statistically significant. AH Plus and Endoflas FS showed a statistically significant difference of 0.04 and 0.001 in between groups, and there was no statistically significant difference in the Tubli-Seal group from Tukey post hoc test. CONCLUSION: The study showed that Endoflas FS sealer has a significant antimicrobial effect against E. faecalis. CLINICAL SIGNIFICANCE: In clinical situation, despite perfect che-momechanical root canal preparation, persistence of microorganisms may reinfect the root canal. Therefore, endodontic root canal sealers play a major role in the eradication of bacteria. The polymicrobial nature of endodontic infection plays a main role during the usage of endodontic sealer with antimicrobial agents, which in turn reduces the failure of endodontic treatment.


Assuntos
Anti-Infecciosos/farmacologia , Sulfato de Bário/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Resinas Epóxi/farmacologia , Hidrocarbonetos Iodados/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Cimento de Óxido de Zinco e Eugenol/farmacologia , Combinação de Medicamentos , Testes de Sensibilidade Microbiana
8.
Dysphagia ; 33(6): 818-826, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29882104

RESUMO

The modified barium swallow study (MBSS) is a commonly used radiographic procedure for diagnosis and treatment of swallowing disorders. Despite attempts by dysphagia specialists to standardize the MBSS, most institutions have not adopted such standardized procedures. High variability of assessment patterns arguably contribute to variability of treatment recommendations made from diagnostic information derived from the MBSS report. An online survey was distributed to speech-language pathologists (SLPs) participating in American Speech Language Hearing Association (ASHA) listservs. Sixty-three SLPs who treat swallowing disorders participated. Participating SLPs reviewed two MBSS reports and chose physiologic treatment targets (e.g., tongue base retraction) based on each report. One report primarily contained symptomatology (e.g., aspiration, pharyngeal residue) with minimal information on impaired physiology (e.g., laryngeal incompetence, reduced hyolaryngeal elevation/excursion). In contrast, the second report contained a clear description of impaired physiology to explain the dysphagia symptoms. Fleiss kappa coefficients were used to analyze inter-rater agreement across the high and low physiology report types. Results revealed significantly higher inter-rater agreement across clinicians when reviewing reports with clear explanation(s) of physiologic impairment relative to reports that primarily focused on symptomatology. Clinicians also reported significantly greater satisfaction and treatment confidence following review of reports with clear description(s) of impaired physiology.


Assuntos
Sulfato de Bário/farmacologia , Transtornos de Deglutição/diagnóstico , Deglutição/fisiologia , Fluoroscopia/métodos , Laringe/diagnóstico por imagem , Faringe/diagnóstico por imagem , Atitude do Pessoal de Saúde , Meios de Contraste/farmacologia , Transtornos de Deglutição/fisiopatologia , Transtornos de Deglutição/terapia , Humanos , Laringe/fisiopatologia , Otorrinolaringologistas , Planejamento de Assistência ao Paciente , Seleção de Pacientes , Faringe/fisiopatologia , Reprodutibilidade dos Testes , Estados Unidos
9.
Radiology ; 288(1): 245-251, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29737955

RESUMO

Purpose To prospectively compare small bowel distention provided by, as well as patient acceptance of, two different neutral (negative) oral contrast materials used for cross-sectional enterography in a pediatric population. Materials and Methods In this noninferiority study, 66 pediatric patients undergoing clinical computed tomographic (CT) or magnetic resonance (MR) enterography were randomized to receive either a flavored beverage for neutral abdominal and pelvic imaging (Breeza; Beekley Medical, Bristol, Conn) or a low-density barium sulfate suspension. Patients were blinded to the oral contrast material administered and were asked to rate taste, texture, and their perceived health state (where 0 was very bad and 10 was very good). Ingested volume of the prescribed weight-based oral contrast material preparation was recorded. Maximum small bowel diameter was measured in all four abdominal quadrants. Mean bowel diameter as well as taste, texture, and health state scores were compared between cohorts by using t tests; proportions were compared by using Fisher exact tests. Results Thirty-three patients each received Breeza and barium sulfate suspension, respectively. No difference was found in age (Breeza, 13.5 years ± 2.6 [standard deviation]; barium sulfate suspension, 13.9 years ± 2.8; P = .49), sex distribution (15 girls each; P > .99), or health state (P = .21) between cohorts. Twenty-eight of 33 (84.8%) and 17 of 33 (51.5%) patients completed the Breeza and barium sulfate suspension preparations, respectively (P = .007). Breeza received higher scores for taste (6.1 ± 2.5 vs 2.7 ± 2.5; P < .0001) and texture (7.3 ± 2.3 vs 3.6 ± 2.9; P < .0001). No difference was found in bowel distention between Breeza and barium sulfate suspension (1.63 cm ± 0.24 vs 1.69 cm ± 0.25; P = .44). Conclusion The neutral oral contrast materials Breeza and low-density barium sulfate suspension provide similar small bowel distention. Patients receiving Breeza are more likely to ingest the entire prescribed volume.


Assuntos
Sulfato de Bário/farmacologia , Bebidas , Meios de Contraste/farmacologia , Aumento da Imagem/métodos , Intestino Delgado/diagnóstico por imagem , Satisfação do Paciente/estatística & dados numéricos , Abdome/diagnóstico por imagem , Administração Oral , Adolescente , Meios de Contraste/administração & dosagem , Dilatação Patológica/induzido quimicamente , Feminino , Humanos , Intestino Delgado/efeitos dos fármacos , Imageamento por Ressonância Magnética , Masculino , Pediatria/métodos , Pelve/diagnóstico por imagem , Estudos Prospectivos , Paladar , Tomografia Computadorizada por Raios X/métodos
10.
Anticancer Res ; 38(1): 247-251, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29277779

RESUMO

BACKGROUND: Maintaining the function of blood vessels is important for the control of hepatocellular carcinoma (HCC) during treatment with repeated transcatheter arterial chemoembolization (TACE). This study was designed to compare the vascular damage caused by miriplatin (MPT), which has been commonly used for TACE, with the damage caused by epirubicin (EPI). MATERIALS AND METHODS: We used the portal vein of healthy rats for the administration of the drug (MPT or EPI) and/or soybean oil as vehicle. After 2 days, angiography was performed by X-ray computer tomography. RESULTS: The influence of soybean oil on blood vessel function was volume-dependent. EPI showed dose-dependent effects on angiography, and 0.5 mg EPI led to severe (grade 4) blood flow disturbance in all animals. The effect of 1 mg MPT on blood vessels was mild (grade 1) in all animals and not different from that of soybean oil alone. CONCLUSION: Less vascular damage is caused by MPT than by EPI, suggesting that MPT is a useful drug for TACE in HCC.


Assuntos
Antineoplásicos/efeitos adversos , Epirubicina/efeitos adversos , Fígado/efeitos dos fármacos , Compostos Organoplatínicos/efeitos adversos , Angiografia , Animais , Antineoplásicos/administração & dosagem , Sulfato de Bário/farmacologia , Quimioembolização Terapêutica , Epirubicina/administração & dosagem , Feminino , Humanos , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Compostos Organoplatínicos/administração & dosagem , Ratos Sprague-Dawley , Óleo de Soja/administração & dosagem , Tomografia Computadorizada por Raios X
11.
Intern Med ; 56(23): 3159-3165, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29021456

RESUMO

Objective This study aimed to evaluate swallowing dysfunction in patients with spinal and bulbar muscular atrophy and to identify the most appropriate method of assessing swallowing dysfunction using a videofluoroscopic swallowing study. Methods In the videofluoroscopic swallowing study, patients were instructed to swallow 3 mL of 40% weight/volume barium sulfate twice, and the pharyngeal residue was measured. We used three different methods to quantify the pharyngeal barium residue and an eight-point scale to evaluate the laryngeal penetration leading to aspiration pneumoniae. Patients We assessed 111 patients with spinal and bulbar muscular atrophy who weren't undergoing disease-specific treatment. Results Our results showed that the pharyngeal barium residue after initial swallowing correlated better with the bulbar-related functional rating scales than that after multiple deglutition. This correlation was vague when the data from patients whose barium residue was >50% were eliminated. In addition, evaluating the pharyngeal residue after initial swallowing proved to be the most sensitive method with regard to laryngeal penetration. Conclusion This study showed that the pharyngeal barium residue after initial swallowing was the most appropriate parameter for quantitatively assessing the degree of dysphagia using a videofluoroscopic swallowing study and suggests that this method may predict laryngeal penetration and aspiration in patients with spinal and bulbar muscular atrophy.


Assuntos
Atrofia Bulboespinal Ligada ao X/complicações , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sulfato de Bário/farmacologia , Atrofia Bulboespinal Ligada ao X/fisiopatologia , Deglutição , Transtornos de Deglutição/fisiopatologia , Feminino , Fluoroscopia/métodos , Humanos , Laringe , Masculino , Pessoa de Meia-Idade , Pneumonia Aspirativa
12.
J Clin Pediatr Dent ; 41(6): 450-455, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28937906

RESUMO

OBJECTIVES: An association between root canal sealers and periapical lesions in primary dentition has been suggested, yet the chemical-protein interactions that may be involved in it have not been studied. The present study explored root sealer components' effect on periapical tissue proteins using bioinformatics tools. STUDY DESIGN: For each chemical component of Endoflas F.S. root sealing material we identified the known and predicted target proteins, using STITCH (search tool for interactions of chemicals http://stitch.embl.de/ ). Identified target proteins were grouped into functional categories using the annotation clustering tool from DAVID, the Database for Annotation, Visualization and Integrated Discovery ( http://david.abcc.ncifcrf.gov/ ). STRING Protein-Protein Interaction network database identified associations between the proteins. RESULTS: Sixteen proteins identified with STITCH served as input to DAVID annotation clustering tool. Only ZnO and Eugenol targeted proteins had statistically significant annotations. Gene Ontology terms of ZnO and Eugenol targeted proteins demonstrated that these proteins respond to mechanical stimulus and to oxidative stress. They highlight these proteins' role in the positive regulation of transcription, gene expression, cell proliferation and apoptosis, and their complementary role in the negative regulation of cell death. CONCLUSION: When stimulated by Zinc Oxide, Eugenol and Calcium hydroxide, chemical-protein and subsequent protein-protein interactions result in cell proliferation in the periapical area. Our findings indicate that certain root sealers components may cause enlargement of the permanent tooth follicle. Dentists should be aware of this phenomenon and radiographically monitor root canal treated teeth until shedding.


Assuntos
Sulfato de Bário/farmacologia , Hidrocarbonetos Iodados/farmacologia , Tecido Periapical/efeitos dos fármacos , Proteínas/efeitos dos fármacos , Proteínas/fisiologia , Cimento de Óxido de Zinco e Eugenol/farmacologia , Combinação de Medicamentos
13.
Mutagenesis ; 32(1): 13-22, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26861493

RESUMO

In the course of a 2-year combined chronic toxicity-carcinogenicity study performed according to Organisation for Economic Co-operation and Development (OECD) Test Guideline 453, systemic (blood cell) genotoxicity of two OECD representative nanomaterials, CeO2 NM-212 and BaSO4 upon 3- or 6-month inhalation exposure to rats was assessed. DNA effects were analysed in leukocytes using the alkaline Comet assay, gene mutations and chromosome aberrations were measured in erythrocytes using the flow cytometric Pig-a gene mutation assay and the micronucleus test (applying both microscopic and flow cytometric evaluation), respectively. Since nano-sized CeO2 elicited lung effects at concentrations of 5mg/m3 (burdens of 0.5mg/lung) in the preceding range-finding study, whereas nano-sized BaSO4 did not induce any effect, female rats were exposed to aerosol concentrations of 0.1 up to 3mg/m3 CeO2 or 50mg/m3 BaSO4 nanomaterials (6h/day; 5 days/week; whole-body exposure). The blood of animals treated with clean air served as negative control, whereas blood samples from rats treated orally with three doses of 20mg/kg body weight ethylnitrosourea at 24h intervals were used as positive controls. As expected, ethylnitrosourea elicited significant genotoxicity in the alkaline Comet and Pig-a gene mutation assays and in the micronucleus test. By contrast, 3- and 6-month CeO2 or BaSO4 nanomaterial inhalation exposure did not elicit significant findings in any of the genotoxicity tests. The results demonstrate that subchronic inhalation exposure to different low doses of CeO2 or to a high dose of BaSO4 nanomaterials does not induce genotoxicity on the rat hematopoietic system at the DNA, gene or chromosome levels.


Assuntos
Aberrações Cromossômicas/induzido quimicamente , Dano ao DNA , Exposição por Inalação , Leucócitos/efeitos dos fármacos , Mutação , Nanoestruturas/toxicidade , Animais , Sulfato de Bário/farmacologia , Sulfato de Bário/toxicidade , Cério/farmacologia , Cério/toxicidade , DNA/efeitos dos fármacos , Feminino , Leucócitos/metabolismo , Testes de Mutagenicidade , Nanoestruturas/química , Ratos
14.
Dis Esophagus ; 29(1): 22-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25327483

RESUMO

Barium esophagrams are a frequently performed test, and radiological observations about potential abnormal esophageal motility, such as tertiary contractions, are commonly reported. We sought to assess the correlation between tertiary waves, and in particular isolated tertiary waves, on esophagrams and findings on non-synchronous high-resolution esophageal manometry. We retrospectively reviewed reports of esophagrams performed at a tertiary referral center and identified patients in whom tertiary waves were observed and a high-resolution esophageal manometry had been performed. We defined two groups; group 1 was defined as patients with isolated tertiary waves, whereas group 2 had tertiary waves and evidence of achalasia or an obstructing structural abnormality on the esophagram. We collected data on demographics, dysphagia score, associated findings on esophagram, and need for intervention. We reviewed the reports of 2100 esophagrams of which tertiary waves were noted as an isolated abnormality in 92, and in association with achalasia or a structural obstruction in 61. High-resolution manometry was performed in 17 patients in group 1, and five had evidence of a significant esophageal motility disorder and 4 required any intervention. Twenty-one patients in group 2 underwent manometry, and 18 had a significant esophageal motility disorder. An isolated finding of tertiary waves on an esophagram is rarely associated with a significant esophageal motility disorder that requires intervention. All patients with isolated tertiary waves who required intervention had a dysphagia to liquids. Tertiary contractions, in the absence of dysphagia to liquids, indicate no significant esophageal motility disorder.


Assuntos
Transtornos da Motilidade Esofágica , Esôfago , Adulto , Idoso , Sulfato de Bário/farmacologia , Meios de Contraste/farmacologia , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/fisiopatologia , Transtornos da Motilidade Esofágica/diagnóstico , Transtornos da Motilidade Esofágica/fisiopatologia , Esôfago/diagnóstico por imagem , Esôfago/fisiopatologia , Feminino , Humanos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Peristaltismo/fisiologia , Radiografia , Estudos Retrospectivos , Estatística como Assunto
15.
Eur Arch Otorhinolaryngol ; 273(3): 735-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25708412

RESUMO

Recurrent neck lesions associated with third or fourth branchial arch fistula are much less common than those of second arch and usually present with acute suppurative thyroiditis or neck abscess. Our aim is to describe clinical features, management and treatment outcomes of 64 cases of congenital pyriform sinus fistula (PSF). Medical record of these 64 patients (33 males, 31 females) treated at the First Affiliated Hospital of Zhengzhou University from 2011 to 2014 were reviewed. The patients comprised 33 males and 31 females, and their ages ranged from 18 months to 47 years (median 10 years, mean 12.7 years). Neck abscess and recurrent infection was the mode of presentation in 37 cases (57.8 %), 4 patients (6.3 %) presented with acute suppurative thyroiditis, neck mass was the mode of presentation in 17 cases (26.6 %), 2 patients (3.1 %) presented with neck mass with respiratory distress, and cutaneous discharging fistula was the mode of presentation in 1 cases (1.6 %). The remaining 3 patients (4.7 %) presented with cutaneous discharging fistula with neck infection. Investigations performed include barium swallow, CT scan, and ultrasound which were useful in delineating PSF tract preoperatively. Barium swallow was taken as the gold standard for diagnosis. Our patients were treated by fistulectomy with hemithyroidectomy, fistulectomy, fistulectomy with endoscopic electric cauterization, endoscopic electric cauterization or endoscopic coblation cauterization, respectively. Histopathologic examination of the surgical specimens revealed that they were lined with ciliated epithelium, stratified cuboid epithelium with chronic inflammatory cell infiltration and fibrosis. Voice hoarseness occurred after operation in seven patients, but disappeared 1 week later. PSF recurred in 6 patients, 4 of them were cured by a successful re-excision. One patient was cured by successful endoscopic electric cauterization. The other 1 has remained asymptomatic for 5 months. In our series, mean follow-up period was 13.3 months and median follow-up period was 12.5 months (range 2-40 months). Presence of congenital PSF should be suspected when intra-thyroidal abscess formation occurs as the gland is resistant to infection. Strong clinical suspicion, barium swallow study, CT scan and ultrasound are the key to diagnosis. Both fistulectomy with hemithyroidectomy and endoscopic treatment have comparable success rate. Endoscopic coblation cauterization may prove a useful and equally effective method of treatment for PSF in future.


Assuntos
Abscesso , Cauterização , Cirurgia Endoscópica por Orifício Natural , Pescoço , Seio Piriforme , Fístula do Sistema Respiratório , Tireoidectomia , Tireoidite Supurativa , Abscesso/diagnóstico , Abscesso/etiologia , Abscesso/cirurgia , Adolescente , Sulfato de Bário/farmacologia , Região Branquial/anormalidades , Cauterização/efeitos adversos , Cauterização/métodos , China , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Cirurgia Endoscópica por Orifício Natural/efeitos adversos , Cirurgia Endoscópica por Orifício Natural/métodos , Pescoço/diagnóstico por imagem , Pescoço/cirurgia , Seio Piriforme/anormalidades , Seio Piriforme/cirurgia , Recidiva , Reoperação/métodos , Fístula do Sistema Respiratório/complicações , Fístula do Sistema Respiratório/congênito , Fístula do Sistema Respiratório/diagnóstico , Fístula do Sistema Respiratório/fisiopatologia , Estudos Retrospectivos , Tireoidectomia/efeitos adversos , Tireoidectomia/métodos , Tireoidite Supurativa/diagnóstico , Tireoidite Supurativa/etiologia , Tireoidite Supurativa/cirurgia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
16.
Methods Mol Biol ; 1309: 227-37, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25981779

RESUMO

Magnetic gradients have the valuable property of exerting a repulsive ponderomotive force onto diamagnetic compounds. A carefully designed gradient and proper positioning of biological material can be used to manipulate gravisensing organelles such as amyloplasts of higher plants and other statoliths such as the BaSO4-filled vesicles of Characean algae. This chapter describes the main considerations of magnetic gradients and their application as a localized force field to manipulate (sort) cellular organelles based on their magnetic properties. Many of the inferences from such activities have yet to be investigated.


Assuntos
Caráceas/crescimento & desenvolvimento , Sensação Gravitacional , Campos Magnéticos , Plastídeos/efeitos da radiação , Actinas/metabolismo , Sulfato de Bário/farmacologia , Caráceas/efeitos dos fármacos , Caráceas/efeitos da radiação , Plastídeos/efeitos dos fármacos , Plastídeos/metabolismo
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 137-47, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25218222

RESUMO

In the present study, we reported that the synthesis and characterization of pure and diverse mole Co-doped BaSO4 nanoparticles have been synthesized by chemical precipitation technique. X-ray diffraction analysis (XRD) brought out the information about the synthesized products is orthorhombic structure and highly crystalline in nature. The average grain size of the samples was determined by using the Debye-Scherer's equation. The existence of functional groups and band area of the samples were confirmed by Fourier transform infrared (FTIR) spectroscopy. The direct and indirect band gap energy of pure and doped samples was carried out using UV-VIS-DRS. The surface micrograph, morphological distribution and elemental compositions of the synthesized products were assessed by scanning electron microscopy (SEM) and Energy dispersive X-ray (EDS). Thermo gravimetric and differential thermal analysis (TG-DTA) techniques were analyzed thermal behaviour of pure and Co-doped samples. Finally, antibacterial activities found the Gram-positive and Gram-negative bacteria are more active in transporter, dehydrogenize and periplasmic enzymatic activities of pure and doped samples.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Sulfato de Bário/síntese química , Sulfato de Bário/farmacologia , Precipitação Química , Cobalto/química , Nanopartículas/química , Antibacterianos/química , Bactérias/efeitos dos fármacos , Sulfato de Bário/química , Análise Diferencial Térmica , Humanos , Luz , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura , Espalhamento de Radiação , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Termogravimetria , Difração de Raios X
18.
Patol Fiziol Eksp Ter ; (3): 89-93, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26852602

RESUMO

We investigated contribution mediator mechanism in the development of the phenomenon of inhibition induced by barium sulfate luminol-dependent chemiluminescence (SLCHL) of blood under the influence of nonsteroidal anti-inflammatory drugs (NSAIDs) in patients with intolerance to these drugs. It was found that the phenomenon of suppression SLCHL blood under the influence of NSAIDs in patients with intolerance is mediated by the participation of mediators, and the contribution of H1--and H2--histamine receptors, 5-HT2 serotonin receptors and Cys-leukotriene receptors in the development of that phenomenon depends on the chemical nature of NSAIDs and the clinical manifestations of intolerance.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Sulfato de Bário/farmacologia , Hipersensibilidade a Drogas/sangue , Mediadores da Inflamação/sangue , Medições Luminescentes , Luminol/farmacologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Head Neck ; 37(8): 1193-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25044292

RESUMO

BACKGROUND: The purpose of this study was to determine if persistent changes in the duration of bolus movement through the pharynx and bolus movement coordination with pharyngeal swallowing gestures occur after treatment of oropharyngeal carcinoma with chemoradiation therapy. METHODS: The timing of bolus movement and coordination with swallowing gestures was evaluated in 30 patients using a modified barium swallowing study at least 1 year after completion of treatment. Patients were recruited irrespective of any swallowing complaints. The mean of each measure from the study subjects was compared to those from a group of age-matched controls. RESULTS: Bolus transit duration in the study population was unchanged compared with normal controls. Unlike normal controls, the patients were found to allow the bolus to arrive in the vallecula before the initiation of swallowing gestures that resulted in a swallow. Earlier opening of the upper esophageal sphincter was found for a 1-cc bolus (p = .004). For the 20 cc bolus size, the onset of hyoid and aryepiglottic fold elevation was delayed (p = .029 and .037, respectively). Gesture timing did not change to accommodate larger bolus sizes, as it normally does, resulting in a delay in airway protection for the 20-cc bolus. CONCLUSION: Patients are able to move a liquid bolus through the pharynx in a timely manner. However, patients are unable to modify swallowing gestures to safely protect the airway.


Assuntos
Carcinoma/terapia , Quimiorradioterapia/efeitos adversos , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Deglutição , Neoplasias Orofaríngeas/terapia , Idoso , Sulfato de Bário/farmacologia , Estudos de Casos e Controles , Meios de Contraste/farmacologia , Fluoroscopia , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Medição de Risco , Fatores de Tempo , Gravação em Vídeo
20.
J Biomed Mater Res A ; 102(1): 141-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23613219

RESUMO

Monitoring the degradation of calcium phosphate-based bone substitute materials in vivo by means of noninvasive techniques (e.g., radiography) is often a problem due to the chemical resemblance of those substitutes with the mineral phase of bone. In the view of that, the present study aimed at enhancing the radiopacity of calcium phosphate cement enriched with poly(lactic-co-glycolic acid) (CPC-PLGA) microspheres, by adding tantalum oxide (Ta2O5) or the more traditional radiopacifier barium sulfate (BaSO4). The radiopacifying capacity of these radiopacifiers was first evaluated in vitro by microcomputed tomography (µCT). Thereafter, both radiopacifiers were tested in vivo using a distal femoral condyle model in rabbits, with subsequent ex vivo µCT analysis in parallel with histomorphometry. Addition of either one of the radiopacifiers proved to enhance radiopacity of CPC-PLGA in vitro. The in vivo experiment showed that both radiopacifiers did not induce alterations in biological performance compared to plain CPC-PLGA, hence both radiopacifiers can be considered safe and biocompatible. The histomorphometrical assessment of cement degradation and bone formation showed similar values for the three experimental groups. Interestingly, µCT analysis showed that monitoring cement degradation becomes feasible upon incorporation of either type of radiopacifier, albeit that BaSO4 showed more accuracy compared to Ta2O5.


Assuntos
Sulfato de Bário/farmacologia , Substitutos Ósseos/farmacologia , Fosfatos de Cálcio/farmacologia , Meios de Contraste/farmacologia , Fêmur/diagnóstico por imagem , Ácido Láctico/farmacologia , Óxidos/farmacologia , Ácido Poliglicólico/farmacologia , Tantálio/farmacologia , Microtomografia por Raio-X , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos
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