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1.
Cureus ; 16(4): e58806, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38784366

RESUMEN

BACKGROUND: Dentinal hypersensitivity is a brief and painful oral condition that is characterized by an abrupt shooting sensation. Stimulation occurs when hot, cold, sweet, or sour food comes into contact with exposed dentinal tubules. The present study used a scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDX) to investigate the efficacy of Er: YAG, 810 nm diode LASER, and NovaMin Technology in obstructing dentinal tubules. MATERIAL AND METHODS: We extracted the outer layers of 30 human teeth to expose the tubules and then treated the surfaces with 17% ethylenediaminetetraacetic acid (EDTA) to create an etched effect. Three cohorts were created from the portions. Group A was subjected to the application of Erbium:Yttrium-Aluminum-Garnet (Er: YAG) laser with a power output of 2W in the non-contact mode for 1 minute. Group B was subjected to the application of an 810nm diode laser with a power output of 1W in continuous mode for 30 seconds. Group C was subjected to the application of NovaMin paste, which contains a 927 ppm fluoride content. Following the therapy, occluded dentinal tubules were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) for both quantitative and qualitative examination. The data analysis was conducted using a one-way analysis of variance (ANOVA) and Tukey's test, with a significance threshold of 0.05. RESULTS: The average percentages of complete blockage of dentinal tubules in Groups A, B, and C were evaluated using the number of entirely unobstructed dentinal tubules at magnifications of 2000X (F = 3.05, p = 0.064), 5000X (F = 5.33, p = 0.011), and 10000X (F = 8.63, p = 0.001). The count of partially open dentinal tubules seen at magnifications of 2000X, 5000X, and 10000X was F = 10.15 (P < 0.001), F = 5.97 (p = 0.007), and F = 2.12 (p = 0.140) accordingly. CONCLUSION: NovaMin technology has demonstrated more effectiveness in blocking dentinal tubules compared to 810nm diodes and Er: YAG lasers.

2.
Cureus ; 16(3): e55384, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38562336

RESUMEN

INTRODUCTION: The spleen is one of the frequently injured solid organs in abdominal blunt trauma. The standard of care is nonoperative nowadays depending on the hemodynamic stability (World Society of Emergency Surgery (WSES) grade I-III) of the patient due to advancements in treating modalities. Operative interventions are required in hemodynamically unstable patients or failure of nonoperative management. The study was planned to find the clinical spectrum of abdominal blunt trauma, specifically those having splenic trauma, and their subsequent management in an institution. METHODS: This is a retrospective observational study. All included patients with blunt abdominal injuries were treated in a level 1 trauma center between July 2021 and December 2022. Data regarding demographic profile, blood transfusion, pre- and postoperative findings, and management including the period of hospital stay, morbidity, and mortality were collected and analyzed. RESULTS: One hundred sixty-four patients were analyzed, of which 142 were males and 22 were females. The commonest mechanism of injury was motor vehicle collision, followed by falls. Grade III splenic injury was the most common injury, while the predominantly associated injury was rib fracture. The patients were managed preferably through nonoperative management, followed by angioembolization and operative management. The commonest postoperative complication was pneumonia. CONCLUSIONS: Nonoperative management of splenic trauma has evolved as the standard of care replacing operative management in order to sustain its immune function, thereby preventing overwhelming post-splenectomy infection.

3.
RSC Adv ; 14(10): 6762-6775, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38405071

RESUMEN

In this study, we employed density functional theory coupled with the full-potential linearized augmented plane-wave method (FP-LAPW) to investigate the structural, electronic, and magnetic properties of the Ti2FeAs alloy adopting the Hg2CuTi-type structure. Our findings demonstrate that all the examined structures exhibit ferromagnetic (FM) behaviour. By conducting electronic band structure calculations, we observed an energy gap of 0.739 eV for Ti2FeAs in the spin-down state and metallic intersections at the Fermi level in the spin-up state. These results suggest the half-metallic (HM) nature of Ti2FeAs, where the Ti-d and Fe-d electronic states play a significant role near the Fermi level. Additionally, the obtained total magnetic moments are consistent with the Slater-Pauling rule (Mtot = Ztot - 18), indicating 100% spin polarization for these compounds. To explore their optical properties, we employed the dielectric function to compute various optical parameters, including absorption spectra, energy-loss spectra, refractive index, reflectivity, and conductivity. Furthermore, various thermodynamic parameters were evaluated at different temperatures and pressures. The results obtained from the elastic parameters reveal the anisotropic and ductile nature of the Ti2FeAs compound. These findings suggest that Ti2FeAs has potential applications in temperature-tolerant devices and optoelectronic devices as a UV absorber.

4.
RSC Adv ; 14(6): 4165-4178, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38292271

RESUMEN

In this study, the density functional theory (DFT) was employed to study the structural, electronic, optical, and thermoelectric characteristics of half-Heusler (HH) FeTaX (X = P or As). Optimization of the structures was achieved using Perdew-Burke-Ernzerhof (PBE) parametrized generalized gradient approximation (GGA). These HH FeTaX (X = P, As) showed indirect bandgaps of 0.882 eV and 0.748 eV, respectively. The predicted density of states (DOS) spectra suggest that Fe-d and Ta-d states contribute predominantly to both valence and conduction bands, whereas P/As-p states contribute less. Optical properties were investigated to assess their potential in optoelectronic applications. The estimated values of various optical parameters and low loss suggest that the studied HH FeTaX (X = P, As) are suitable for optoelectronic device applications. The thermoelectric responses of the studied HH FeTaX (X = P, As) were computed, and their highest power factors at high temperature reflects their usage in thermoelectric devices.

5.
Indian J Dent Res ; 34(1): 40-44, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37417055

RESUMEN

Background: Apicoectomy conceptualizes surgically maintaining a tooth with an endodontic lesion that cannot be resolved by conventional endodontic (re-) treatment. To achieve this, continuous improvement in surgical techniques, materials and instruments is being done to enhance the outcome of periapical endodontic surgeries. The purpose of this study was to compare, radiographically, the healing kinetics of platelet-rich fibrin (PRF) and mineralized freeze-dried bone allograft (FDBA) in patients undergoing apicoectomy. Materials and Methods: Nineteen patients (aged 18-40 years) were included in the study and randomly assigned to groups A or B, where they received PRF or FDBA, respectively. Following apicoectomy, PRF gel and FDBA graft were prepared and placed in the osseous defect followed by placement of PRF membrane for graft stabilization and flap closure. Radiographic follow-up was done at the 1st, 3rd, 6th and 12th months for evaluation of healing using Molven's criteria. Statistical analysis was done with Pearson's and McNemar's Chi-square tests. Results: A highly significant difference (P = 0.002) in radiographic healing was observed at 6 months. Complete healing was observed in 50% of cases in Group A whereas in Group B, none of the cases presented with complete radiographic healing. However, at the end of 12 months, complete radiographic healing was observed in both groups. Conclusion: Our data suggest that PRF accelerates bone healing as compared to FDBA and is both time and cost-efficient.


Asunto(s)
Fibrina Rica en Plaquetas , Humanos , Aloinjertos/patología , Aloinjertos/trasplante , Apicectomía , Cicatrización de Heridas
6.
J Family Med Prim Care ; 9(8): 4086-4091, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33110814

RESUMEN

CONTEXT: Several studies have reported that PD-L1 has shown therapeutic activity in various tumor types. However, its expression changes in a person on administration of NAC which is reported by very few studies. AIMS: To find out the difference in the expression of PD-L1 by tumor cells after the administration of NAC. SETTINGS AND DESIGN: This prospective study was conducted on 30 patients who were diagnosed with locally advanced breast carcinoma (LABC) between 2017 and 2019 and those who received NAC followed by surgery. METHODS AND MATERIAL: Breast cancer specimens were collected using core needle biopsy prior to administration of NAC and IHC was performed. Frequency and staining intensity of PD-L1 by tumor cells were analyzed. PD-L1 expression was dichotomized into two groups according to the frequency distributions of the H-scores. STATISTICAL ANALYSIS USED: The differences in expression of PD-L1 along with various parameters were analyzed using Chi-square test and Student's t test. RESULTS: The mean age of the patients in our study was 51.37 ± 11.37 years. The response of NAC according to the RECIST criteria showed that most of patients (83.3%) showed complete response. Of the 30 cases, 11 (36.7%) patients were PD-L1 positive before the administration of NAC. We found a significant change in expression from positive to negative status, i.e., seven patients changed from positive to negative (p = 0.036). Upon comparing the PD-L1 expression before NAC, significant association was observed between the primary tumor (T) and tumor stage with high PD-L1 expression (p = 0.020 and P = 0.034). After NAC, 18 (69.2%) patients who were ER positive and 18 (69.2%) patients who were PR positive showed negative PD-L1 expression while none of them were positive in PD-L1 positive patients (p = 0.018 and P = 0.018). CONCLUSION: PD-L1 expression in a same person changes upon administration of NAC which may indirectly be used as a predictor of response to NAC.

7.
Front Chem ; 8: 704, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32923427

RESUMEN

The search for new topological materials that are realistic to synthesize has attracted increasing attention. In this study, we systematically investigated the electronic, mechanical, and topological semimetallic properties, as well as the interesting surface states, of the tetragonal monoxide of platinum, which is realistic to synthesize, via a first-principles approach. Our calculated results indicate that PtO is a novel topological semimetal with double nodal lines in the k z = 0 plane and a pair of triple topological nodal points along the A'-M-A directions. Obvious surface states, including Fermi arc and drum-head-like surfaces, could be found around nodal points and nodal lines. The dynamic and mechanical stabilities of P4 2 /mmc-type PtO were examined in detail via calculation of the phonon dispersion and determination of elastic constants, respectively. Some other mechanical properties, including the bulk modulus, Young's modulus, shear modulus, Poisson's ratio, and Pugh's index, were considered in this study. P4 2 /mmc-type PtO provides a good research platform for investigation of novel behaviors that combine mechanical properties and rich topological elements.

8.
J Mol Graph Model ; 94: 107463, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31593919

RESUMEN

The electronic structures of AuCu3-type XAl3 (X = Sc, Yb, Lu) compounds have been calculated using full potential linearized augmented plane wave (FP-LAPW) method within the density functional theory. The calculations have been performed using PBE-GGA, WC-GGA and PBE-sol GGA approximations. Electronic structures in these materials confirm metallicity. Our estimated ground state properties in case of ScAl3 are found in good agreement with the experimental values, while for YbAl3 and LuAl3 couldn't be compared owing to non-existence of data. Charge density plots illustrate Sc/Yb/Lu-Al bonds are covalent, which signify according to Poisson ratio. For this reason, various elastic modulii, bulk to shear modulus ratios, Cauchy pressures were determined and it was found that XAl3 compounds show brittle nature. Finally, specific heat capacity, Debye temperature and Grüneisen parameter under pressure (0-15 GPa) and temperature (0-1000 K) are also elucidated using quasi harmonic model.


Asunto(s)
Electrónica , Electrones , Temperatura , Termodinámica
9.
RSC Adv ; 9(17): 9522-9532, 2019 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35520698

RESUMEN

In the present paper, double perovskite Ba2InTaO6 was investigated in terms of its structural, electronic, optical, elastic, mechanical, thermodynamic and thermoelectric properties using density-functional theory (DFT). The generalized gradient approximation (GGA) in the scheme of Perdew, Burke and Ernzerhof (PBE) and the modified Becke-Johnson (mBJ) potential were employed for the exchange-correlation potential. The computed lattice constant was found to be in agreement with the available experimental and theoretical results. The electronic profile shows a semiconducting nature. Further analysis of the complex dielectric constant ε(ω), refractive index n(ω), reflectivity R(ω), absorption coefficient α(ω), optical conductivity (ω) and energy loss function were also reported with the incident photon energy. The elastic constants were also calculated and used to determine mechanical properties like Young's modulus (Y), the shear modulus (G), Poisson's ratio (ν) and the anisotropic factor (A). The electrical conductivity (σ/τ) and Seebeck coefficient (S) also demonstrated the semiconducting nature of the compound with electrons as the majority carriers. The value of the power factor was calculated to be 1.20 × 1012 W K-2 m-1 s-1 at 1000 K. From thermodynamic investigations, the heat capacity and Grüneisen parameter were also predicted.

10.
J Mol Model ; 24(3): 52, 2018 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-29441416

RESUMEN

High pressure electronic, elastic, mechanical, and thermodynamic properties of cubic perovskite SnTaO3 have been explored with density function theory (DFT), and the quasi-harmonic Debye model has been applied for the incorporation of high temperature. The experimental lattice constant has been used for the optimization of structure. The optimization results present the paramagnetic (PM) nature of the compound. The spin dependent electronic band structures at ambient conditions and under high pressure present the metallic nature with complete uniformity for the majority and minority spin states. The mechanical properties, such as Young's modulus and bulk modulus, have been calculated and suggest an increase in stiffness and hardness of the material under the application of pressure. The thermodynamic properties, such as specific heat and Grüneisen parameter, have been predicted in the temperature range of 0 to 1000 K and pressure range of 0 to 60 Gpa.

12.
Chemosphere ; 154: 590-598, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27088536

RESUMEN

Eight in situ solidification/stabilization (ISS) amendments were tested to promote in situ chemical oxidation (ISCO) with activated persulfate (PS) in a contaminated soil. A 3% (by weight) dose of all ISS amendments selected for this study completely activated a 1.5% dose of PS within 3 h by raising temperatures above 30 °C (heat activation) and/or increasing pH above 10.5 (alkaline activation). Heat is released by the reaction of CaO with water, and pH increases because this reaction produces Ca(OH)2. Heat activation is preferred because it generates 2 mol of oxidizing radicals per mole of PS, whereas alkaline activation releases only 1. The relative contribution of heat vs. alkaline activation increased with CaO content of the ISS amendment, which was reflected by enhanced contaminant oxidation with increasing CaO content, and was confirmed by comparing to controls promoting purely heat or alkaline (NaOH) activation. The test soil was contaminated with benzene, toluene, ethylbenzene, and xylenes (BTEX) and polycyclic aromatic hydrocarbons (PAH), particularly naphthalene (NAP). ISS-activated PS oxidized between 47% and 84% of the BTEX & NAP, and between 13% and 33% of the higher molecular weight PAH. ISS-activated PS reduced the leachability of BTEX & NAP by 76%-91% and of the 17 PAH by 83%-96%. Combined ISCO/ISS reduced contaminant leachability far than ISCO or ISS treatments alone, demonstrating the synergy that is possible with combined remedies.


Asunto(s)
Derivados del Benceno/aislamiento & purificación , Naftalenos/aislamiento & purificación , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Compuestos de Sodio/química , Contaminantes del Suelo/aislamiento & purificación , Suelo/química , Sulfatos/química , Benceno/química , Benceno/aislamiento & purificación , Derivados del Benceno/química , Biodegradación Ambiental , Naftalenos/química , Oxidación-Reducción , Hidrocarburos Policíclicos Aromáticos/química , Contaminantes del Suelo/química , Tolueno/química , Tolueno/aislamiento & purificación , Xilenos/química , Xilenos/aislamiento & purificación
14.
J Hazard Mater ; 297: 347-55, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26093352

RESUMEN

Laboratory batch reactors were maintained for 32 weeks to test the potential for an in situ remedy that combines chemical oxidation, stabilization, and anaerobic bioremediation in a single application to treat soil from a manufactured gas plant, contaminated with polycyclic aromatic hydrocarbons (PAH) and benzene, toluene, ethylbenzene, and xylenes (BTEX). Portland cement and slaked lime were used to activate the persulfate and to stabilize/encapsulate the contaminants that were not chemically oxidized. Native sulfate-reducing bacteria degraded residual contaminants using the sulfate left after persulfate activation. The ability of the combined remedy to reduce contaminant mass and leachability was compared with NaOH-activated persulfate, stabilization, and sulfate-reducing bioremediation as stand-alone technologies. The stabilization amendments increased pH and temperature sufficiently to activate the persulfate within 1 week. Activation with both stabilization amendments and NaOH removed between 55% and 70% of PAH and BTEX. However, combined persulfate and stabilization significantly reduced the leachability of residual BTEX and PAH compared with NaOH activation. Sulfide, 2-naphthoic acid, and the abundance of subunit A of the dissimilatory sulfite reductase gene (dsrA) were used to monitor native sulfate-reducing bacteria, which were negatively impacted by activated persulfate, but recovered completely within weeks.


Asunto(s)
Biodegradación Ambiental , Oxígeno/química , Hidróxido de Sodio/química , Contaminantes del Suelo/análisis , Suelo , Sulfatos/química , Anaerobiosis , Benceno/análisis , Derivados del Benceno/análisis , Materiales de Construcción , Agua Subterránea , Concentración de Iones de Hidrógeno , Naftalenos/química , Hidrocarburos Policíclicos Aromáticos/análisis , Suelo/química , Sulfuros/química , Temperatura , Tolueno/análisis , Contaminantes del Agua/análisis , Xilenos/análisis
15.
Indian J Dent Res ; 25(1): 78-82, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24748305

RESUMEN

LASER (Light Amplification by Stimulated Emission of Radiation) is a powerful source of light, which has innumerable applications in all the fields of science including medicine and dentistry. It is one such technology that has become a desirable and an inseparable alternative to many traditional surgical procedures being held in the field of dentistry, and orthodontics is no exception. The current article describes the uses of a diode laser as an indispensable tool in an orthodontic office.


Asunto(s)
Terapia por Luz de Baja Intensidad , Ortodoncia/instrumentación , Biopsia , Humanos , Trastornos de la Articulación Temporomandibular/terapia
17.
Amino Acids ; 39(5): 1493-505, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20473534

RESUMEN

Anti-bacterial drug resistance is one of the most critical concerns among the scientist worldwide. The novel antimicrobial decapeptide SD-8 is designed and its minimal inhibitory concentration and therapeutic index (TI) was found in the range of 1-8 µg/ml and 45-360, respectively, against major group of Gram positive pathogens (GPP). The peptide was also found to be least hemolytic at a concentration of 180 µg/ml, i.e., nearly 77 times higher than its average effective concentration. The kinetics assay showed that the killing time is 120 min for methicillin-sensitive Staphylococcus aureus (MSSA) and 90 min for methicillin-resistant S. aureus (MRSA). Membrane permeabilization is the cause of peptide antimicrobial activity as shown by the transmission electron microscopy studies. The peptide showed the anti-inflammatory property by inhibiting COX-2 with a KD and Ki values of 2.36×10(-9) and 4.8×10(-8) M, respectively. The peptide was also found to be effective in vivo as derived from histopathological observations in a Staphylococcal skin infection rat model with MRSA as causative organism.


Asunto(s)
Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Cocos Grampositivos/efectos de los fármacos , Péptidos/farmacología , Animales , Antibacterianos/sangre , Antibacterianos/química , Péptidos Catiónicos Antimicrobianos/sangre , Péptidos Catiónicos Antimicrobianos/química , Cromatografía Líquida de Alta Presión , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa 2/sangre , Inhibidores de la Ciclooxigenasa 2/química , Inhibidores de la Ciclooxigenasa 2/farmacología , Modelos Animales de Enfermedad , Cocos Grampositivos/crecimiento & desarrollo , Hemólisis , Humanos , Cinética , Pruebas de Sensibilidad Microbiana , Péptidos/sangre , Péptidos/química , Ratas , Ratas Wistar , Piel/efectos de los fármacos , Piel/lesiones , Piel/patología , Solubilidad , Resonancia por Plasmón de Superficie
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