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1.
J Chem Theory Comput ; 20(11): 4778-4789, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38775818

RESUMO

Conical intersection (CI) seams are configuration spaces of a molecular system where two or more (spin) adiabatic electronic states are degenerate in energy. They play essential roles in photochemistry because nonradiative decays often occur near the minima of the seam, i.e., the minimum energy CIs (MECIs). Thus, it is important to explore the CI seams and discover the MECIs. Although various approaches exist for CI seam exploration, most of them are local in nature, requiring reasonable initial guesses of geometries and nuclear gradients during the search. Global search algorithms, on the other hand, are powerful because they can fully sample the configurational space and locate important MECIs missed by local algorithms. However, global algorithms are often computationally expensive for large systems due to their poor scalability with respect to the number of degrees of freedom. To overcome this challenge, we develop the parallel on-the-fly Crystal algorithm to globally explore the CI seam space, taking advantage of its superior scaling behavior. Specifically, Crystal is coupled with on-the-fly evaluations of the excited and ground state energies using multireference electronic structure methods. Meanwhile, the algorithm is parallelized to further boost its computational efficiency. The effectiveness of this new algorithm is tested for three types of molecular photoswitches of significant importance in material and biomedical sciences: photostatin (PST), stilbene, and butadiene. A rudimentary implementation of the algorithm is applied to PST and stilbene, resulting in the discovery of all previously identified MECIs and several new ones. A refined version of the algorithm, combined with a systematic clustering technique, is applied to butadiene, resulting in the identification of an unprecedented number of energetically accessible MECIs. The results demonstrate that the parallel on-the-fly Crystal algorithm is a powerful tool for automated global CI seam exploration.

2.
J Comput Chem ; 45(15): 1261-1278, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38635333

RESUMO

In this work, the Crystal  code, developed previously by the authors to find "holes" as well as legitimate transition states in existing potential energy surface (PES) functions [JPC Lett. 11, 6468 (2020)], is retooled to perform on-the-fly "direct dynamics"-type PES explorations, as well as automatic construction of new PES functions. In all of these contexts, the chief advantage of Crystal  over other methods is its ability to globally map the PES, thereby determining the most relevant regions of configuration space quickly and reliably-even when the dimensionality is rather large. Here, Crystal  is used to generate a uniformly spaced grid of density functional theory (DFT) or ab initio points, truncated over the relevant regions, which can then be used to either: (a) hone in precisely on PES features such as minima and transition states, or; (b) create a new PES function automatically, via interpolation. Proof of concept is demonstrated via application to three molecular systems: water (H 2 O), (reduced-dimensional) methane (CH 4 ), and methylene imine (CH 2 NH).

3.
Nanoscale ; 16(9): 4678-4690, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38317511

RESUMO

The NLRP3 inflammasome, a multiprotein complex responsible for triggering the release of pro-inflammatory cytokines, plays a crucial role in inducing the inflammatory response associated with sepsis. While small molecule inhibitors of the NLRP3 inflammasome have been investigated for sepsis management, delivering NLRP3 inhibitors has been accompanied by several challenges, primarily related to the drug formulation, delivery route, stability, and toxicity. Many existing inflammasome inhibitors either show higher liver toxicity or require a high dosage to efficiently impede the inflammasome complex assembly. Moreover, the potential synergistic effects of combining multiple inflammasome inhibitors in sepsis therapy remain largely unexplored. Therefore, a rational approach is essential for presenting the potential administration of NLRP3 small molecule inhibitors to inhibit NLRP3 inflammasome activation effectively. In this context, we present a lipid nanoparticle-based dual-drug delivery system loaded with MCC 950 and disulfiram, demonstrating markedly higher efficiency compared to an equivalent amount of free-drug combinations and individual drug nanoparticles in vitro. This combination therapy substantially improved the in vivo survival rate of mice for LPS-induced septic peritonitis. Additionally, the synergistic approach illustrated a significant reduction in the expression of active caspase-1 as well as IL-1ß inhibition integral components in the NLRP3 pathway. This study underscores the importance of integrating combination therapies facilitated by nanoparticle delivery to address the limitations of small molecule inflammasome inhibitors.


Assuntos
Inflamassomos , Sepse , Animais , Camundongos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Caspase 1/metabolismo , Citocinas , Sepse/tratamento farmacológico , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia
4.
Front Cell Dev Biol ; 11: 1271178, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37766964

RESUMO

Introduction: Cranial neural crest (CNC) cells are induced at the border of the neural plate by a combination of FGF, Wnt, and BMP4 signaling. CNC then migrate ventrally and invade ventral structures where they contribute to craniofacial development. Methods: We used loss and gain of function experiments to determine phenotypes associated with the perturbation of Adam11 expression in Xenopus Laevis. Mass spectrometry to identify partners of Adam11 and changes in protein expression in CNC lacking Adam11. We used mouse B16 melanoma to test the function of Adam11 in cancer cells, and published database analysis to study the expression of ADAM11 in human tumors. Results: Here we show that a non-proteolytic ADAM, Adam11, originally identified as a putative tumor suppressor binds to proteins of the Wnt and BMP4 signaling pathway. Mechanistic studies concerning these non-proteolytic ADAM lack almost entirely. We show that Adam11 positively regulates BMP4 signaling while negatively regulating ß-catenin activity. In vivo, we show that Adam11 influences the timing of neural tube closure and the proliferation and migration of CNC. Using both human tumor data and mouse B16 melanoma cells, we further show that ADAM11 levels similarly correlate with Wnt or BMP4 activation levels. Discussion: We propose that ADAM11 preserves naïve cells by maintaining low Sox3 and Snail/Slug levels through stimulation of BMP4 and repression of Wnt signaling, while loss of ADAM11 results in increased Wnt signaling, increased proliferation and early epithelium to mesenchyme transition.

5.
bioRxiv ; 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37398217

RESUMO

Cranial neural crest (CNC) cells are induced at the border of the neural plate by a combination of FGF, Wnt, and BMP4 signaling. CNC then migrate ventrally and invade ventral structures where they contribute to craniofacial development. Here we show that a non-proteolytic ADAM, Adam11, originally identified as a putative tumor suppressor binds to proteins of the Wnt and BMP4 signaling pathway. Mechanistic studies concerning these non-proteolytic ADAM lack almost entirely. We show that Adam11 positively regulates BMP4 signaling while negatively regulating ß-catenin activity. By modulating these pathways, Adam11 controls the timing of neural tube closure and the proliferation and migration of CNC. Using both human tumor data and mouse B16 melanoma cells, we further show that ADAM11 levels similarly correlate with Wnt or BMP4 activation levels. We propose that ADAM11 preserve naïve cells by maintaining low Sox3 and Snail/Slug levels through stimulation of BMP4 and repression of Wnt signaling, while loss of ADAM11 results in increased Wnt signaling, increased proliferation and early epithelium to mesenchyme transition.

6.
J Phys Chem A ; 127(31): 6385-6399, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37494557

RESUMO

The ongoing shift toward clean, sustainable energy is a primary driving force behind hydrogen fuel research. Safe and effective storage of hydrogen is a major challenge (particularly for mobile applications) and requires a detailed understanding of the atomic level interactions of hydrogen with its host materials. The light mass of hydrogen, however, implies that quantum effects are important, so a quantum dynamical treatment is required to properly account for these effects in computational simulations. As one such example, we describe herein the hydrogen exchange dynamics between a hydride and a dihydrogen ligand in the [FeH(H2)(PH3)4]+ model complex. A global three-dimensional (3D) potential energy surface (PES) was constructed by fitting to and interpolating from a discrete set of grid points computed using density functional theory; exact quantum dynamical calculations were then carried out on the 3D PES using discrete variable representation basis sets. Energy levels and their quantum tunneling splittings were computed up to 3000 cm-1 above the ground state. Within that energy range, all three fundamentals have been identified using wave function plots, as well as the first three overtones of the exchange (reaction coordinate) motion and several of its combination bands. From the tunneling splittings, the Boltzmann-averaged tunneling rates were computed. The Arrhenius plot of the total exchange rate shows a clear transition around 150 K, below which the activation energy is essentially zero and above which it is less than half of the electronic structure barrier. This indicates that exchange rates are governed by quantum tunneling throughout the relevant temperature range with the low-temperature regime dominated by a single quantum (ground) state. This work is the first-ever fully quantum dynamical study to investigate the hydrogen exchange dynamics between hydride and dihydrogen ligands coordinated to a transition-metal complex.

7.
Development ; 150(4)2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36789951

RESUMO

Monoclonal antibodies are powerful and versatile tools that enable the study of proteins in diverse contexts. They are often utilized to assist with identification of subcellular localization and characterization of the function of target proteins of interest. However, because there can be considerable sequence diversity between orthologous proteins in Xenopus and mammals, antibodies produced against mouse or human proteins often do not recognize Xenopus counterparts. To address this issue, we refined existing mouse monoclonal antibody production protocols to generate antibodies against Xenopus proteins of interest. Here, we describe several approaches for the generation of useful mouse anti-Xenopus antibodies to multiple Xenopus proteins and their validation in various experimental approaches. These novel antibodies are now available to the research community through the Developmental Study Hybridoma Bank (DSHB).


Assuntos
Anticorpos Monoclonais , Proteínas de Xenopus , Animais , Camundongos , Hibridomas , Xenopus laevis , Proteínas de Xenopus/genética
8.
Head Neck Pathol ; 16(3): 645-650, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34751896

RESUMO

The current pandemic of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a global, unanticipated public health crisis. Another emerging challenge is the prevalence of "black fungus", or mucormycosis, among patients who recovered from COVID-19 infection. A retrospective study was conducted on 12 patients in a post-COVID recovery phase who developed mucormycosis. The study parameters evaluated lymphocyte count, CD4+ T cell status, and associated systemic co-morbidities for the patient, namely diabetes. The interventions during the treatment for COVID were also recorded to include administration of oxygen, ventilator assistance (invasive and non-invasive)/oxygen support, and steroid use. The possible relationship between low lymphocyte and CD4+ counts with diabetes and fungal growth was evaluated. It was observed that the majority of the patients who had a positive history for diabetes with low lymphocyte and CD4+ counts were more susceptible to opportunistic fungal infections. Most of the patients, but not all, had a history of receiving oxygen or assisted ventilation, as well as steroids, during the treatment for COVID infection. These interventions may be considered as accessory contributing factors for fungal infection. Post-exposure to SARS-CoV-2, therapies should be targeted at prevention of functional exhaustion of lymphocytes and maintaining optimal lymphocyte and subset counts in susceptible hosts for the prevention of opportunistic fungal infections. The relationship between functional exhaustion of the lymphocyte, diabetes, and COVID mandates further research.


Assuntos
COVID-19 , Diabetes Mellitus , Mucormicose , Micoses , Humanos , Oxigênio , Estudos Retrospectivos , SARS-CoV-2
9.
IEEE Trans Nanobioscience ; 21(2): 175-183, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34928801

RESUMO

Silicon (Si)-based mid-infrared (MIR) photonics has promising potential for realizing next-generation ultra-compact spectroscopic systems for various applications such as label-free and damage-free gas sensing, medical diagnosis, and defense. The epitaxial growth of Ge1-xSnx alloy on Si substrate provides the promising technique to extend the cut-off wavelength of Si photonics to MIR range by Sn alloying. Here, we present the theory and simulation of heterojunction p-i-n MIR photodetectors (PDs) with Ge0.87Sn0.13/Ge0.92Sn0.08 quantum-wells with an additional Ge0.91Sn0.09 layer to elongate the photoabsorption path in the MIR spectrum. The incorporation of QW pairs (N) enables the light-matter interaction due to the carrier and optical confinement in the active region. As a result, the spectral response of the device is enhanced in the MIR range. Devices with varying N were compared in terms of various figure-of merits including dark-current, a photocurrent-to-dark current ratio, detectivity, spectral responsivity, and noise equivalent power (NEP). Additionally, parasitic capacitance-dependent RC and 3dB bandwidth were also studied using a small-signal equivalent circuit model. The proposed device exhibited the extended photodetection wavelength at  âˆ¼ 3370 nm and [Formula: see text] up to  âˆ¼ 7.3×103 with a dark current of  âˆ¼ 56.3 nA for N=8 at 300 K. At a bias of -3V, the proposed device achieved the spectral responsivity of 0.86 A/W at 2870 nm and 0.55 A/W at 3300 nm, detectivity more than 2.5×109 Jones and a NEP less than 2.1×10-13 WHz-0.5 for N=8 at 3250 nm. The calculated 3dB bandwidth of 47.8 GHz, the signal-to-noise ratio (SNR), and linear dynamic range (LDR) of 93 dB and 74 dB were achieved at 3300 nm for N=8 . Thus, these results indicate that the proposed GeSn-based QW p-i-n PDs pave the pathway towards the realization of new and high-performance detectors for sensing in the MIR regime.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33882814

RESUMO

Cancer, a set of diseases characterized by abnormal cell growth resulting from alteration in the expression pattern of diverse genes, is one of the prominent causes of mortality and morbidity worldwide. This modification of various genes leads to altered signalling cascades and changes in the molecular network. These changes eventually give rise to cellular dysfunction and then to systemic failure causing death. Of the several pathways that are aberrantly activated in cancer, Notch signalling pathway is a prominent one. Notch signalling pathway is a juxtracrine signalling pathway which activates the genes associated with cell proliferation, survival and angiogenesis. Notch signalling pathway components are seen to be upregulated in several types of cancer. Oral squamous cell carcinoma (OSCC) is a predominant category of oral cancer where aberrant activation of Notch signalling causes tumour progression and metastasis. In this review, we discuss the Notch signalling pathway, its components, forms and its role in the progression and metastasis of oral squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Humanos , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Receptores Notch/genética , Receptores Notch/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço
11.
J Phys Chem Lett ; 11(15): 6468-6474, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32687368

RESUMO

Potential energy surfaces (PESs) play an indispensable role in molecular dynamics but are notoriously difficult to flesh out properly in large-dimensional spaces. In particular, the undetected presence of PES holes, i.e., unphysical saddle points beyond which the potential energy drops arbitrarily, can have devastating effects on both classical and quantum dynamics calculations. In this study, the Crystal algorithm is developed as a tool for efficiently and accurately finding PES holes, as well as legitimate saddle points, even in very large-dimensional configuration spaces. The approach is applied to three large-dimensional PESs for molecular systems of current interest: uracil, naphthalene, and formic acid dimer. Low-lying PES holes are discovered and located for the first two systems-including naphthalene, for which no holes were previously suspected, to the best of our knowledge. Likewise, the double-well, double-proton-transfer isomerization saddle point for formic acid dimer is also located.

12.
J Chem Phys ; 152(21): 214102, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32505158

RESUMO

We have developed an algorithm to detect holes in multi-dimensional real-valued surfaces-such as the potential energy surfaces (PESs) that describe the nuclear motion of molecules in the context of the Born-Oppenheimer approximation. For our purposes, a PES "hole" is defined as an unphysical saddle point, beyond which the potential energy drops (typically) without limit to negative infinity. PES holes are numerical artifacts that can arise when fitting PES functional forms to discrete ab initio data-even when the data is of high quality, and/or for comparatively few degrees of freedom (DOF). Often undetected, PES holes can have devastating effects on subsequent dynamical calculations, especially if they occur at low energies. In this paper, we present a highly efficient algorithm designed to systematically identify hole configurations and energies. The method is applied to a variety of molecular PESs ranging up to 30 DOF. A number of evidently previously undetected PES holes are reported here-surprisingly, even for PESs that have been available for decades. The code itself (Crystal) is presented together with a user manual. These tools may be of great benefit for PES developers, who can use the information they provide to fix holes, once identified. More generally, the methodology can be applied in any context involving multi-dimensional surfaces.

13.
Materials (Basel) ; 13(7)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244720

RESUMO

This paper reports on high-accuracy simulation of a grating structure based fiber optic plasmonic sensor for salivary cortisol sensing. Gratings of SiO2 and SiC (one at a time) in combination with a thin Ag layer are considered to be in direct contact with analyte medium (solutions containing different concentrations of cortisol) considering that the groove regions are also filled with analyte. The optimization of Ag layer thickness is carried out to achieve maximum power loss (PL) corresponding to cortisol concentration variation. The variation of PL (in dB) spectra with the angle of incidence (α) is the sensing mechanism of the proposed scheme. Sensing performance is extensively analyzed in terms of sensitivity, limit-of-detection (LOD) and figure-of-merit (FOM) that incorporates both the sensitivity and the width of the corresponding PL curves. While the sensitivity and FOM values are significantly large, the results also reveal that in angular interrogation mode (AIM), an average LOD of 9.9 pg/mL and 9.8 pg/mL is obtained for SiO2 and SiC-based sensor designs, respectively. When the intensity interrogation method (IIM) in place of AIM is considered, an average LOD of 22.6 fg/mL and 68.17 fg/mL is obtained for SiO2 and SiC-based sensor designs, respectively. LOD (with IIM, in particular) is considerably better than the present-state-of-art related to cortisol monitoring. Pragmatic model for possible practical implementation of sensor scheme is also discussed. The involvement of optical fiber in the proposed sensor design makes it possible to implement it as a flexible sensor or for wearable solution for cortisol detection via sweat monitoring as well as for measuring cortisol level in aquaculture tanks where concentration levels are much lower than 10 ng/mL.

14.
Indian J Crit Care Med ; 24(1): 66-68, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32148352

RESUMO

The annual incidence rates of venous thromboembolism are approximately 1 per 1,000 persons per year in adult population. Deep vein thrombosis (DVT) most frequently occurs in the setting of underlying illness, and anatomical abnormalities are rarely considered as an etiology for it. A well-described anatomical cause for DVT is "May-Thurner syndrome" (MTS), which occurs as a result of compression of the left common iliac vein by the overlying right common iliac artery. This syndrome most often affects young to middle-aged women. Pulmonary embolism (PE) occurs very rarely in these patients. Anticoagulation therapy alone is not enough in these patients. We report a case of 27-year-old male who had both left DVT and PE caused by MTS and was treated with endovascular management along with long-term anticoagulation. HOW TO CITE THIS ARTICLE: Baburao A, Singh A, Babu A, Pandey A. May-Thurner Syndrome: A Forgotten Cause of Venous Thromboembolism. Indian J Crit Care Med 2020;24(1):66-68.

15.
J Chem Phys ; 151(1): 014114, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31272171

RESUMO

In this article, we use momentum-symmetrized phase-space Gaussians to calculate the vibrational energy eigenstates of the OCHCO+ cation. A potential energy surface provided by Bowman's group was used, albeit refit to a sixth order anharmonic force field. We have developed the "Crystal" algorithm to implement various basis set truncation strategies for our calculations. These calculations were performed using the SwitchBLADE code, designed by our group, which constructs and diagonalizes the vibrational Hamiltonian matrix in order to compute energy eigenstates. A theoretical overview of the Crystal algorithm is presented, as is a discussion of how best to truncate the basis for a floppy double-well system. Specific vibrational transition frequency results for OCHCO+ are also presented and analyzed.

16.
Appl Opt ; 58(16): 4518-4525, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251266

RESUMO

Two-dimensional (2D) heterostructure-based fluoride fiber surface plasmon resonance (SPR) sensor designs are simulated and analyzed while emphasizing figure of merit (FOM) enhancement in the near-infrared (NIR) spectral region. Through simultaneous optimization of NIR wavelength and Ag layer thickness, exceptionally large FOM values of 15,650.75 RIU-1 and 12,409.30 RIU-1 are achieved for BlueP/MoS2-based and BlueP/WS2-based fiber SPR sensors, respectively. The results are explained in terms of tunable radiation damping, power loss, and corresponding field enhancement. These FOM values are significantly greater than recently reported sensors. The BlueP/MoS2-based sensor with 48.8 nm Ag film and at 738.4 nm wavelength provides an all-round large FOM.

17.
Materials (Basel) ; 12(9)2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083414

RESUMO

Two-dimensional (2D) heterostructure materials show captivating properties for application in surface plasmon resonance (SPR) sensors. A fluoride fiber-based SPR sensor is proposed and simulated with the inclusion of a 2D heterostructure as the analyte interacting layer. The monolayers of two 2D heterostructures (BlueP/MoS2 and BlueP/WS2, respectively) are considered in near infrared (NIR). In NIR, an HBL (62HfF4-33BaF2-5LaF3) fluoride glass core and NaF clad are considered. The emphasis is placed on figure of merit (FOM) enhancement via optimization of radiation damping through simultaneous tuning of Ag thickness (dm) and NIR wavelength (λ) at the Ag-2D heterostructure-analyte interfaces. Field distribution analysis is performed in order to understand the interaction of NIR signal with analyte at optimum radiation damping (ORD) condition. While the ORD leads to significantly larger FOM for both, the BlueP/MoS2 (FOM = 19179.69 RIU-1 (RIU: refractive index unit) at dm = 38.2 nm and λ = 813.4 nm)-based sensor shows massively larger FOM compared with the BlueP/WS2 (FOM = 7371.30 RIU-1 at dm = 38.2 nm and λ = 811.2 nm)-based sensor. The overall sensing performance was more methodically evaluated in terms of the low degree of photodamage of the analyte, low signal scattering, high power loss, and large field variation. The BlueP/MoS2-based fiber SPR sensor under ORD conditions opens up new paths for biosensing with highly enhanced overall performance.

18.
J Indian Prosthodont Soc ; 18(3): 226-230, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30111911

RESUMO

STATEMENT OF PROBLEM: Various osteotomy modalities seem to have an impact on the primary and secondary stability of the dental implant. The available literature lacks the comparison of various available osteotomy modalities used for the dental implant placement and its effects on the initial surgical bone removal. PURPOSE: The purpose of this study is to compare and evaluate the osteotomy sites created using standard drill, bone trephine, and alveolar expanders for dental implant surgery. MATERIALS AND METHODS: The study was done on ten goat hemimandibles. Three osteotomy sites were prepared at the inferior border of the mandible using standard drill, trephine, and alveolar expander in each hemimandibles and the sites were subjected to cone-beam computed tomography (CBCT). The CBCT images obtained were compared for the amount of cortical bone and bone marrow loss at osteotomy sites in different techniques. RESULTS: The mean and standard deviation of loss of cortical bone with standard drills, trephines, and alveolar expanders was 3.62 ± 4.216 × 10-2, 3.6 ± 4.681 × 10-16 and 3.15 ± 7.071 × 10-2. At the middle-third region, the loss of marrow bone was 3.38 ± 7.88 × 10-2, 2.15 ± 8.498 × 10-2 and 0.03 ± 9.487 × 10-2, and at lower third region, it was 2.3 ± 4.714 × 10-2, 0.02 ± 6.325 × 10-2, and 0.0, respectively. CONCLUSION: CBCT images showed minimum bone loss with the use of alveolar expander which may be due to the lateral bone condensation rather the removal of the marrow. Trephine showed less marrow removal in comparison to the standard drill used for dental implant surgery.

19.
J Maxillofac Oral Surg ; 17(1): 71-74, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29382998

RESUMO

PURPOSE: The aim of the study is to compare the post reduction squealae of transmucosal miniplate fixation technique for stabilization of palatal fractures with intra-arch wiring technique. MATERIALS AND METHOD: This study was prospectively undertaken on 16 patients, dividing them into two treatment arms based on random sampling methodology (Group A & B). For patients in Group A, intra-arch wire stabilization technique and in Group B trans-mucosal miniplate stabilization technique was used. The pre-operative and post-operative occlusion and time taken for stabilization in both the techniques was compared. RESULTS: The mean time taken for reduction and stabilization of palatal fracture in group A was 10.9 ± 2.21 min and in group B was 14.2 ± 1.13 min. Four out of eight study patients in group A required post reduction interception to stabilize occlusion postoperatively, whereas none of the patients in group B needed any post operative intervention. CONCLUSION: The post operative occlusal stability was found better in study patients included in group B when compared to group A patients, although satisfactory post-operative occlusion was obtained even in group A with post-operative interception for occlusal stability.

20.
Oral Maxillofac Surg ; 20(3): 259-64, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27283723

RESUMO

PURPOSE: To determine systemic absorption of dexamethasone by detection of plasma concentration using high performance liquid chromatography following its administration along with local anesthetic agent as a mixture via pterygomandibular space. METHODS: A prospective randomized double-blind clinical study was undertaken to analyze the plasma concentration of dexamethasone after intra-space pterygomandibular injection along with local anesthesia. The study was performed as per split mouth model where the mandibular quadrant allocation was done on a random basis considering each of the 30 patients is included in the two study interventions (SS and CS). For the study site (SS) procedures, dexamethasone was administered as a mixture (2 % lignocaine with 1:200,000 epinephrine and 4 mg dexamethasone) intra-space. In the control site (CS) procedures, a regular standard inferior alveolar nerve block was administered, and dexamethasone was given as intramuscular injection. The plasma dexamethasone determination was done in venous blood 30- and 60-min post injection using high performance liquid chromatography (HPLC). The clinical parameters like pain; swelling; and mouth opening on the first, third, and seventh post-operative day were analyzed and compared. RESULTS: No significant difference was found in the clinical parameters assessed; comparative evaluation showed less swelling in the SS interventions. The plasma concentration of dexamethasone for the CS interventions was 226 ± 47 ng/ml at 30-min and 316 ± 81.6 ng/ml at 60-min post injection, and for SS, it was 221 ± 81.6 ng/ml at 30-min and 340 ± 105 ng/ml at 60-min post injection. On inter-site (CS and SS) comparison, no statistically significant difference was ascertained in dexamethasone plasma concentration at 30-min post injection (P = 0.77) and at 60-min post injection. (P = 0.32). CONCLUSION: Intra-space (pterygomandibular space) administration of dexamethasone can achieve statistically similar plasma concentration of the drug as when the same dose is administered intramuscularly with demonstration of similar clinical effects.


Assuntos
Anestesia Dentária , Anestesia Local , Cromatografia Líquida de Alta Pressão/métodos , Dexametasona/administração & dosagem , Dexametasona/farmacocinética , Epinefrina/administração & dosagem , Lidocaína/administração & dosagem , Dente Serotino/cirurgia , Absorção pela Mucosa Oral , Extração Dentária , Adulto , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Injeções , Masculino , Mandíbula/efeitos dos fármacos , Estudos Prospectivos , Escala Visual Analógica
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