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1.
J Hum Hypertens ; 37(8): 701-708, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36008598

RESUMO

Previous work in mouse models shows that urinary TNF-α levels become elevated when dietary salt (NaCl) intake increases. To examine if this relationship exists in humans, we conducted a secondary analysis of the Dietary Approaches to Stop Hypertension (DASH)-Sodium trial to determine levels of urinary TNF-α in 367 subjects categorized by race, sex, and blood pressure. The DASH-Sodium trial is a multicenter feeding trial in which subjects were randomly assigned to either the DASH or control diet, and high, medium, and low sodium in random order. Multivariable linear regression was used to model baseline TNF-α and a mixed model was used to model TNF-α as a function of dietary intervention. At baseline, with all subjects on a "typical American diet", urinary TNF-α levels were lowest in Black, p = 0.002 and male subjects, p < 0.001. After randomization to either the DASH or control diet, with increasing levels of sodium, urinary TNF-α levels increased only in subjects on the control diet, p < 0.05. As in the baseline analysis, TNF-α levels were highest in White females, then White males, Black females and lowest in Black males. The results indicate that urinary TNF-α levels in DASH-Sodium subjects are regulated by NaCl intake, modulated by the DASH diet, and influenced by both race and sex. The inherent differences between subgroups support studies in mice showing that increases in renal TNF-α minimize the extent salt-dependent activation of NKCC2.


Assuntos
Abordagens Dietéticas para Conter a Hipertensão , Hipertensão , Sódio na Dieta , Feminino , Humanos , Masculino , Animais , Camundongos , Sódio/urina , Fator de Necrose Tumoral alfa , Cloreto de Sódio , Fatores Raciais , Dieta Hipossódica , Pressão Sanguínea , Cloreto de Sódio na Dieta
2.
Artigo em Inglês | MEDLINE | ID: mdl-35712686

RESUMO

Background and objectives: In recent years, immune-checkpoint inhibitors (ICIs) particularly atezolizumab is on the rise in treating advanced malignancies. With its increased clinical use, various electrolyte abnormalities have been reported in the literature. In this review, we have addressed the question of significant electrolyte abnormalities associated with atezolizumab. Materials and methods: Following PRISMA guidelines, we performed a thorough literature search in four databases including PubMed, Cochrane Library, Embase, and Clinicaltrials.gov. We included only randomized controlled trials from 2010 till March 2021. After a comprehensive screening of 1587 articles, we selected 14 articles for our review and tabulated the results. Following MeSH terms were used: "electrolyte abnormalities", "immune checkpoint inhibitors", "atezolizumab". Results: Non-small cell lung cancer (n = 1270) and metastatic urothelial carcinoma (n = 1164) were the most common malignancies among 3160 patients. The most common electrolyte abnormality was hypomagnesemia (4.7%). Hyponatremia, hypophosphatemia, hypercalcemia and hypokalemia were found in 2.3%, 0.63%, 0.25% and 0.06% patients respectively. For patients taking atezolizumab, hypomagnesemia was most frequently found in non-small cell lung carcinoma patients (9.4%), while urothelial metastatic carcinoma patients most commonly had hyponatremia (5.15%). Hypokalemia though insignificant was observed only in patients with metastatic renal cell carcinoma (2.85%). Conclusion: Since the use of atezolizumab is on the rise for the treatment of various cancers, more studies need to be conducted to better understand its safety and toxicity profile.

3.
J Inorg Biochem ; 165: 128-135, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27453532

RESUMO

New first-row transition-metal compounds with the ligand norharmane (9H-Pyrido[3,4-b]indole; Hnor) are reported. The compounds have the general formula [M(LL)(Hnor)(NO3)2](MeOH)0-1 (M=Co, Ni, Cu, Zn; LL=2,2'-bipyridyl (bpy), 1,10-phenanthroline (phen)) and have been characterized by physical and analytical methods. X-ray structural analysis revealed that the compound of formula [Cu(phen)(Hnor)(NO3)2], (1) has a distorted 6-coordinated octahedrally-based geometry, with a planar-based [CuN3O] core, where Cu-L varies between 1.99 and 2.04Å and two weak axial CuO contacts (2.209 and 2.644Å) from two different nitrates. Based on spectroscopic similarities, the other compounds appear to have the same or very similar coordination geometries. The compounds showed clear cell growth inhibitory effects in two different cancer cell lines in vitro, with the copper and zinc complexes being the most toxic and in fact almost comparable to cisplatin. Flow-cytometry analysis confirmed induction of apoptosis in cancer cells treated with the compounds. Interestingly, co-incubation of the cells with metal complexes and CuCl2 induced an increase in the cytotoxic effects, most likely due to the conversion of the metal compounds in the corresponding, and most active, copper analogues.


Assuntos
Carbolinas , Citotoxinas , Metais/química , Células A549 , Carbolinas/química , Carbolinas/farmacologia , Cisplatino/química , Cisplatino/farmacologia , Citotoxinas/síntese química , Citotoxinas/química , Citotoxinas/farmacologia , Humanos
4.
Artigo em Inglês | MEDLINE | ID: mdl-27002605

RESUMO

We have synthesized two new complexes of platinum (1) and ruthenium (2) with α-amino acid, l-alanine, and 2,3-dihydroxybenzaldehyde derived Schiff base (L). The ligand and both complexes were characterized by using elemental analysis and several other spectroscopic techniques viz; IR, (1)H, (13)C NMR, EPR, and ESI-MS. Furthermore, the protein-binding ability of synthesized complexes was monitored by UV-visible, fluorescence and circular dichroism techniques with a model protein, human serum albumin (HSA). Both the PtL2 and RuL2 complexes displayed significant binding towards HSA. Also, in vitro cytotoxicity assay for both complexes was carried out on human hepatocellular carcinoma cancer (HepG2) cell line. The results showed concentration-dependent inhibition of cell viability. Moreover, the generation of reactive oxygen species was also evaluated, and results exhibited substantial role in cytotoxicity.


Assuntos
Aminoácidos/farmacologia , Complexos de Coordenação/farmacologia , Platina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Rutênio/farmacologia , Bases de Schiff/farmacologia , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Complexos de Coordenação/síntese química , Células Hep G2 , Humanos , Concentração Inibidora 50 , Cinética , Lisossomos/metabolismo , Vermelho Neutro/metabolismo , Ligação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína , Bases de Schiff/síntese química , Albumina Sérica/química , Albumina Sérica/metabolismo , Espectrometria de Fluorescência
5.
J Inorg Biochem ; 153: 346-354, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26384162

RESUMO

Three new compounds containing the bis(triphenylphosphane)iminium cation (PPN(+)) with ClO4(-), BF4(-) and [AgCl2](-) as counter anions have been synthesized and structurally characterized. The two derivatives with ClO4(-) and BF4(-) were found to be isostructural by single crystal X-ray diffraction. Interestingly, the three compounds show extremely potent antiproliferative effects against the human cancer cell line SKOV3. To gain insights into the possible mechanisms of biological action, several intracellular targets have been considered. Thus, DNA binding has been evaluated, as well as the effects of the compounds on the mitochondrial function. Furthermore, the compounds have been tested as possible inhibitors of the seleno-enzyme thioredoxin reductase.


Assuntos
Antineoplásicos/química , Inibidores Enzimáticos/química , Compostos Organometálicos/química , Compostos de Prata/química , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , DNA/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Mitocôndrias/efeitos dos fármacos , Dados de Sequência Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Ligação Proteica , Ratos , Tiorredoxina Dissulfeto Redutase/química , Tiorredoxina Dissulfeto Redutase/metabolismo
6.
ACS Appl Mater Interfaces ; 7(30): 16525-35, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26214855

RESUMO

Understanding the interface-induced effects of heteronanostructured catalysts remains a significant challenge due to their structural complexity, but it is crucial for developing novel applied catalytic materials. This work reports a systematic characterization and catalytic evaluation of MnOx nanoparticle-dispersed CeO2 nanocubes for two important industrial applications, namely, diesel soot oxidation and continuous-flow benzylamine oxidation. The X-ray diffraction and Raman studies reveal an unusual lattice expansion in CeO2 after the addition of MnOx. This interesting observation is due to conversion of smaller sized Ce(4+) (0.097 nm) to larger sized Ce(3+) (0.114 nm) in cerium oxide led by the strong interaction between MnOx and CeO2 at their interface. Another striking observation noticed from transmission electron microscopy, high angle annular dark-field scanning transmission electron microscopy, and electron energy loss spectroscopy studies is that the MnOx species are well-dispersed along the edges of the CeO2 nanocubes. This remarkable decoration leads to an enhanced reducible nature of the cerium oxide at the MnOx/CeO2 interface. It was found that MnOx/CeO2 heteronanostructures efficiently catalyze soot oxidation at lower temperatures (50% soot conversion, T50 ∼660 K) compared with that of bare CeO2 nanocubes (T50 ∼723 K). Importantly, the MnOx/CeO2 heteronanostructures exhibit a noticeable steady performance in the oxidation of benzylamine with a high selectivity of the dibenzylimine product (∼94-98%) compared with that of CeO2 nanocubes (∼69-91%). The existence of a strong synergistic effect at the interface sites between the CeO2 and MnOx components is a key factor for outstanding catalytic efficiency of the MnOx/CeO2 heteronanostructures.

7.
J Inorg Biochem ; 140: 1-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25042730

RESUMO

Four different-anion Ag(I) compounds with the ligand norharmane (9H-Pyrido[3,4-b]indole; Hnor) and having the general formula [Ag(Hnor)2](anion) (anion=ClO4(-), NO3(-) and BF4(-)) [Ag(Hnor)2(MeCN)](PF6) are reported, and studied in detail regarding their coordination mode and in vitro antiproliferative effects. X-ray structural analysis revealed that the complex with the PF6(-) anion has a MeCN solvent molecule weakly coordinated to Ag(I), making the metal coordination T-shaped, while the other compounds present the classical linear Ag(I) coordination. The compounds showed certain cell growth inhibitory effects in two different cancer cell lines, with the perchlorate containing complex being the most toxic and in fact comparable to cisplatin. Notably, the compounds are stable in visible light; and the luminescence in the solid state was found to be extremely weak, whereas in MeOH solution all compounds show a moderate to weak emission band at 375 nm, when excited at 290 nm.


Assuntos
Proliferação de Células/efeitos dos fármacos , Harmina/análogos & derivados , Luz , Neoplasias Pulmonares/patologia , Prata/química , Carbolinas , Linhagem Celular Tumoral , Harmina/síntese química , Harmina/química , Harmina/farmacologia , Humanos , Espectroscopia de Prótons por Ressonância Magnética , Difração de Raios X
8.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): o2246, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22798900

RESUMO

In the crystal structure of the title compound, C(6)H(6)NO(2) (+)·NO(3) (-), the protonated cations are linked by N-H⋯O hydrogen bonds into chains along the b axis. The cations and anions are also linked by N-H⋯O and O-H⋯O hydrogen bonds. C-H⋯O inter-actions also occur. In the cation, the ring makes a dihedral angle of 10.1 (3)° with the carboxylate group.

9.
J Adv Prosthodont ; 4(2): 61-71, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22737309

RESUMO

PURPOSE: To compare the changes in the occlusal vertical dimension, activity of masseter muscles and biting force after insertion of immediate denture constructed with conventional, tooth-supported and Implant-supported immediate mandibular complete denture. MATERIALS AND METHODS: Patients were selected and treatment was carried out with all the three different concepts i.e, immediate denture constructed with conventional (Group A), tooth-supported (Group B) and Implant-supported (Group C) immediate mandibular complete dentures. Parameters of evaluation and comparison were occlusal vertical dimension measured by radiograph (at three different time intervals), Masseter muscle electromyographic (EMG) measurement by EMG analysis (at three different positions of jaws) and bite force measured by force transducer (at two different time intervals). The obtained data were statistically analyzed by using ANOVA-F test at 5% level of significance. If the F test was significant, Least Significant Difference test was performed to test further significant differences between variables. RESULTS: Comparison between mean differences in occlusal vertical dimension for tested groups showed that it was only statistically significant at 1 year after immediate dentures insertion. Comparison between mean differences in wavelet packet coefficients of the electromyographic signals of masseter muscles for tested groups was not significant at rest position, but significant at initial contact position and maximum voluntary clench position. Comparison between mean differences in maximum biting force for tested groups was not statistically significant at 5% level of significance. CONCLUSION: Immediate complete overdentures whether tooth or implant supported prosthesis is recommended than totally mucosal supported prosthesis.

10.
J Adv Prosthodont ; 4(2): 97-102, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22737315

RESUMO

PURPOSE: Study was conducted to determine and assess the effect of different type of denture adhesives on the incisal bite force of complete denture wearers until the dislodgement of upper denture, using pressure transducer. MATERIALS AND METHODS: 30 patients out of 100 were included in the study. Based on the Kapur's method of scoring denture retention and stability, these patients were divided into 3 groups- Group A - Clinically good dentures; Group B - Clinically fair dentures; and Group C - Clinically poor dentures. A custom made occlusal force meter was constructed based on the load cell type of pressure transducers. Different adhesives (powder, paste and adhesive strips) were used in the study. Complete denture wearers were asked to bite on the load cell and the readings of incisal bite force were recorded. The readings of incisal bite force were subjected to statistical analysis using Repeated measures ANOVA followed by post-hoc bonferroni test. RESULTS: The result suggests that denture adhesives improved the incisal bite force of complete denture wearers significantly The incisal bite force (in kg) in Group A without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 2.48 (± 0.16), 3.43 (± 0.11), 6.01 (± 0.11), 3.22 (± 0.09) respectively. The incisal bite force (in kg) in Group B without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 1.87 (± 0.18), 3.35 (± 0.14), 5.34 (± 0.18), 3.21 (± 0.12) respectively. The incisal bite force (in kg) in Group C without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 1.00 (± 0.17), 3.07 (± 0.14), 4.37 (± 0.26), 2.99 (± 0.14) respectively. CONCLUSION: Within the limitations of the study, it was concluded that the use of denture adhesive was found to be significantly effective in improving the incisal bite force of complete dentures until the dislodgement of upper denture. Fittydent paste adhesive was found to be more effective than the powder and strips adhesives. The improvement in incisal bite force was found to be higher in Group C in comparison to that of Group A and Group B.

11.
Dalton Trans ; 41(15): 4566-74, 2012 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-22361783

RESUMO

When the ligand 1,4,5-triazanaphthalene (abbreviated as tan) is reacted with Cu(II) BF(4)(-) and ClO(4)(-) salts, a variety of mononuclear compounds has been found, all with the [Cu(tan)(4)] unit and varying amounts of weakly coordinating axial ligands and lattice solvents. Reproducible compounds formed include two purple compounds, analyzing as [Cu(tan)(4)](ClO(4))(2)(CH(3)OH)(2)(H(2)O) (1) and [Cu(tan)(4)](BF(4))(2)(CH(3)OH)(1.5)(H(2)O) (3), and two blue compounds, analyzing as [Cu(tan)(4)](ClO(4))(2)(H(2)O)(2) (2) and [Cu(tan)(4)](2)(BF(4))(2)(H(2)O)(2) (4). Upon standing at room temperature, red-coloured, mixed-valence dinuclear-based 3D coordination polymers are formed by conversion of the purple/blue products, of which [Cu(2)(tan)(4)](n)(BF(4))(3n) (5) and the isomorphic methanol-water adduct [Cu(tan)(4)](n)(BF(4))(3n)(CH(3)OH)(n)(H(2)O)(5n) (5A) are presented in this paper. In addition a fully reduced dinuclear Cu(I) compound of formula [Cu(2)(tan)(3)(ClO(4))(2)] (7) has been observed, and structurally characterized, as a rare three-blade propeller structure, with a Cu-Cu distance of 2.504 Å.

12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): o302, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22346940

RESUMO

In the title pyrimidine derivative, C(4)H(4)ClN(3), the 2-chloro and 4-amino substituents almost lie in the mean plane of the pyrimidine ring, with deviations of 0.003 (1) Šfor the Cl atom, and 0.020 (1) Šfor the N atom. In the crystal, molecules are linked via pairs of N-H⋯N hydrogen bonds, forming inversion dimers. These dimers are further linked via N-H⋯N hydrogen bonds, forming an undulating two-dimensional network lying parallel to (100).

13.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-32800

RESUMO

PURPOSE: To compare the changes in the occlusal vertical dimension, activity of masseter muscles and biting force after insertion of immediate denture constructed with conventional, tooth-supported and Implant-supported immediate mandibular complete denture. MATERIALS AND METHODS: Patients were selected and treatment was carried out with all the three different concepts i.e, immediate denture constructed with conventional (Group A), tooth-supported (Group B) and Implant-supported (Group C) immediate mandibular complete dentures. Parameters of evaluation and comparison were occlusal vertical dimension measured by radiograph (at three different time intervals), Masseter muscle electromyographic (EMG) measurement by EMG analysis (at three different positions of jaws) and bite force measured by force transducer (at two different time intervals). The obtained data were statistically analyzed by using ANOVA-F test at 5% level of significance. If the F test was significant, Least Significant Difference test was performed to test further significant differences between variables. RESULTS: Comparison between mean differences in occlusal vertical dimension for tested groups showed that it was only statistically significant at 1 year after immediate dentures insertion. Comparison between mean differences in wavelet packet coefficients of the electromyographic signals of masseter muscles for tested groups was not significant at rest position, but significant at initial contact position and maximum voluntary clench position. Comparison between mean differences in maximum biting force for tested groups was not statistically significant at 5% level of significance. CONCLUSION: Immediate complete overdentures whether tooth or implant supported prosthesis is recommended than totally mucosal supported prosthesis.


Assuntos
Humanos , Força de Mordida , Mordeduras e Picadas , Prótese Dentária Fixada por Implante , Prótese Total , Revestimento de Dentadura , Dentaduras , Eletromiografia , Músculo Masseter , Músculos , Próteses e Implantes , Dente , Transdutores , Dimensão Vertical
14.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-25533

RESUMO

PURPOSE: Study was conducted to determine and assess the effect of different type of denture adhesives on the incisal bite force of complete denture wearers until the dislodgement of upper denture, using pressure transducer. MATERIALS AND METHODS: 30 patients out of 100 were included in the study. Based on the Kapur's method of scoring denture retention and stability, these patients were divided into 3 groups- Group A - Clinically good dentures; Group B - Clinically fair dentures; and Group C - Clinically poor dentures. A custom made occlusal force meter was constructed based on the load cell type of pressure transducers. Different adhesives (powder, paste and adhesive strips) were used in the study. Complete denture wearers were asked to bite on the load cell and the readings of incisal bite force were recorded. The readings of incisal bite force were subjected to statistical analysis using Repeated measures ANOVA followed by post-hoc bonferroni test. RESULTS: The result suggests that denture adhesives improved the incisal bite force of complete denture wearers significantly The incisal bite force (in kg) in Group A without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 2.48 (+/- 0.16), 3.43 (+/- 0.11), 6.01 (+/- 0.11), 3.22 (+/- 0.09) respectively. The incisal bite force (in kg) in Group B without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 1.87 (+/- 0.18), 3.35 (+/- 0.14), 5.34 (+/- 0.18), 3.21 (+/- 0.12) respectively. The incisal bite force (in kg) in Group C without using adhesives, with powder adhesive, with paste adhesive and with adhesive strips was found to be 1.00 (+/- 0.17), 3.07 (+/- 0.14), 4.37 (+/- 0.26), 2.99 (+/- 0.14) respectively. CONCLUSION: Within the limitations of the study, it was concluded that the use of denture adhesive was found to be significantly effective in improving the incisal bite force of complete dentures until the dislodgement of upper denture. Fittydent paste adhesive was found to be more effective than the powder and strips adhesives. The improvement in incisal bite force was found to be higher in Group C in comparison to that of Group A and Group B.


Assuntos
Humanos , Adesivos , Força de Mordida , Mordeduras e Picadas , Retenção de Dentadura , Prótese Total , Dentaduras , Polivinil , Leitura , Transdutores de Pressão
15.
J Adv Prosthodont ; 3(4): 186-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22259701

RESUMO

PURPOSE: Porcelain fused to metal (PFM) crowns provide the best treatment option for teeth that have a large or defective restoration. More than 20% of teeth with PFM crowns or bridges require non-surgical root canal treatment (NSRCT). This may be due to the effect of restorative procedures and the possible leakage of bacteria and or their by-products, which leads to the demise of the tooth pulp. Thus, this study was planned to compare the ability of the restorative materials to seal perforated PFM specimens. MATERIALS AND METHODS: The study evaluates the ability of amalgam, composite or compomer restorative materials to close perforated PFM specimen's in-vitro. Ninety PFM specimens were constructed using Ni-Cr alloys and feldspathic porcelain, and then they were divided into 3 groups: amalgam (A), composite + Exite adhesive bond (B) and compomer + Syntac adhesive bond (C). All the PFM samples were embedded in an acrylic block to provide complete sealing of the hole from the bottom side. After the aging period, each group was further divided into 3 equal subgroups according to the thermocycling period (one week for 70 cycles, one month for 300 cycles and three months for 900 cycles). Each subgroup was put into containers containing dye (Pelikan INK), one maintained at 5℃ and the other at 55℃, each cycle for 30 sec time. The data obtained was analyzed by SPSS, 2006 using one way ANOVA test and student t-test and significant difference level at (P<.01). RESULTS: The depth of dye penetration was measured at the interfaces of PFM and filling materials using Co-ordinate Vernier Microscope. The lowest levels of the dye penetration for the three groups, as well as subgroups were during the first week. The values of dye leakage had significantly increased by time intervals in subgroups A and C. CONCLUSION: It was seen that amalgam showed higher leakage than composite while compomer showed the lowest level of leakage.

16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): o2922, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22219954

RESUMO

Both the acetyl and phenyl substituents of the central pyrazole ring in the title compound, C(24)H(20)N(2)O(3)S, are twisted with respect to the pyrazole ring, with the twist involving the phenyl ring being greater [67.4 (1) and 29.6 (2)°]. The tolyl substituent is disordered over two positions in a 1:1 ratio; the mean planes of the aromatic ring are aligned at 67.7 (3) and 69.4 (3)° with respect to the pyrazole ring.

17.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-116677

RESUMO

PURPOSE: Porcelain fused to metal (PFM) crowns provide the best treatment option for teeth that have a large or defective restoration. More than 20% of teeth with PFM crowns or bridges require non-surgical root canal treatment (NSRCT). This may be due to the effect of restorative procedures and the possible leakage of bacteria and or their by-products, which leads to the demise of the tooth pulp. Thus, this study was planned to compare the ability of the restorative materials to seal perforated PFM specimens. MATERIALS AND METHODS: The study evaluates the ability of amalgam, composite or compomer restorative materials to close perforated PFM specimen's in-vitro. Ninety PFM specimens were constructed using Ni-Cr alloys and feldspathic porcelain, and then they were divided into 3 groups: amalgam (A), composite + Exite adhesive bond (B) and compomer + Syntac adhesive bond (C). All the PFM samples were embedded in an acrylic block to provide complete sealing of the hole from the bottom side. After the aging period, each group was further divided into 3 equal subgroups according to the thermocycling period (one week for 70 cycles, one month for 300 cycles and three months for 900 cycles). Each subgroup was put into containers containing dye (Pelikan INK), one maintained at 5degrees C and the other at 55degrees C, each cycle for 30 sec time. The data obtained was analyzed by SPSS, 2006 using one way ANOVA test and student t-test and significant difference level at (P<.01). RESULTS: The depth of dye penetration was measured at the interfaces of PFM and filling materials using Co-ordinate Vernier Microscope. The lowest levels of the dye penetration for the three groups, as well as subgroups were during the first week. The values of dye leakage had significantly increased by time intervals in subgroups A and C. CONCLUSION: It was seen that amalgam showed higher leakage than composite while compomer showed the lowest level of leakage.


Assuntos
Humanos , Adesivos , Envelhecimento , Ligas , Bactérias , Coroas , Porcelana Dentária , Cavidade Pulpar , Dente
18.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 7): o1597, 2009 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21582871

RESUMO

In the title Schiff base, C(18)H(14)N(4)O, the amido -NH- unit is connected to one of the two pyridyl N atoms at an N(-H)⋯N distance of 2.624 (2) Å. The mol-ecular packing features an inter-molecular C-H⋯N R(2) (2)(6) hydrogen-bonding ring motif.

19.
Acta Crystallogr C ; 60(Pt 7): o531-2, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15237188

RESUMO

In the title compound, C18H15OP.C11H8O2, co-crystallization of triphenylphosphine oxide with 1-naphthoic acid yields a supramolecular structure held together by one O-H...O and three C-H...O hydrogen bonds. The O-H...O hydrogen bond [O...O = 2.592 (2) A] has little effect on the O=P bond distance.

20.
Acta Crystallogr C ; 59(Pt 4): O179-80, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12682400

RESUMO

In the title compound, C(18)H(15)OP.C(7)H(5)ClO(2), the triphenylphosphine oxide molecule forms a single directed hydrogen bond with the 3-chlorobenzoic acid molecule, with an O.O=P distance of 2.607 (2) A. The C-Cl and C=O bonds adopt a cisoid conformation in the 3-chlorobenzoic acid molecule.

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