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1.
Eur J Pharmacol ; : 176830, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39032761

RESUMO

Understanding the agonist concentration-response curve (CRC) is the cornerstone in pharmacology. While CRC parameters, agonist potency (EC50) and efficacy (maximum response, Imax) are well-studied, the role of unliganded gating (minimum response, Imin) on CRC is often overlooked. This study explores the effect of unliganded gating on agonist response in muscle-type acetylcholine (ACh) receptors, focusing on the underexplored role of Imin in modulating EC50 and Imax. Three Gain-of-Function (GOF) mutations that increase, and two Loss-of-Function (LOF) mutations that decrease the unliganded gating equilibrium constant (L0) were studied using automated patch-clamp electrophysiology. GOF mutations enhanced agonist potency, whereas LOF mutations reduced it. The calculated CRC aligned well with empirical results, indicating that agonist CRC can be estimated from knowledge of L0. Reduction in agonist efficacy due to LOF mutations was calculated and subsequently validated using single-channel patch-clamp electrophysiology, a factor often obscured in normalized CRC. The study also evaluated the combined impact of mutations (L0) on CRC, confirming the predictive model. Further, no significant energetic coupling between distant residues (>15Å) was found, indicating that the mutations' effects are localized and do not alter overall agonist affinity. These findings substantiate the role of unliganded gating in modulating agonist responses and establishes a predictive model for estimating CRC parameters from known changes in L0. The study highlights the importance of intrinsic activity in receptor theory.

2.
Sci Rep ; 14(1): 12644, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38825631

RESUMO

The present work employs density functional theory to explore the structural, optoelectronic, and thermoelectric attributes of the halide-based double perovskite A2GeSnF6 (A = K, Rb, and Cs) compounds. The stable phonon dispersion spectrum affirms dynamical stability, whereas the enthalpy of formation and tolerance factor evaluated collectively verify structural stability. Considering the Tran Blaha modified Becke Johnson potentials (mBJ), the predicted direct band gaps along the symmetry point are 3.19 eV for K2GeSnF6, 3.16 eV for Rb2GeSnF6 and 3.12 eV Cs2GeSnF6. According to an in-depth examination of the optoelectronic features, A2GeSnF6 (A = K, Rb, and Cs), double perovskites are assuring contenders for optoelectronic devices due to their suitable bandgap. The extremely high figure of merit values (0.94-0.97) obtained from the numerical calculation of power factor and thermal conductivity suggest the intriguing prospects of these compositions for thermoelectric devices. These studies offer a perceptive comprehension of the materials for their potential applications in the future.

3.
Cureus ; 16(5): e60068, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38860103

RESUMO

This case report focuses on the clinical development of a 32-year-old female patient's lobular capillary hemangioma and provides valuable insights into the atypical nature of this tumor. Low-level laser therapy (LLLT) that follows diode laser intervention can be regarded as a novel and evidence-based approach to therapeutic management. The application of a diode laser causes the vascular elements that comprise the bulk of the lesion to coagulate, which in turn causes the lesion's size to decrease. The biological processes that lead to quick tissue regeneration are also activated by LLLT. The suggested therapeutic approach ensures that the patient will heal in the best possible way while also optimizing their comfort and safety. It extends beyond the mere removal of wounds. The case report demonstrates how well dual laser therapy works to lessen common postoperative issues that are commonly seen in traditional surgical therapies for lobular capillary hemangioma such as excessive bleeding and infection. The precise application of the diode laser minimizes damage to surrounding tissues, thereby enhancing the healing process. Additionally, following surgery, LLLT helps reduce pain and inflammation, which improves patient outcomes. The potential of diode laser and LLLT therapies for treating vascular lesions, including lobular capillary hemangioma, is evidenced by their therapeutic advantages. This encourages wider clinical applications and field research. The presented case report offers valuable clinical significance by highlighting an innovative therapeutic approach for lobular capillary hemangioma, a vascular lesion that can present challenges in management.

4.
Cureus ; 16(4): e58347, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38756302

RESUMO

Clinicians should be well-versed in the anatomy, variations, and teeth anomalies. Developmental disturbances of the teeth can lead to alterations in size, shape, number, structure, and eruption of the teeth. Developmental disturbances can lead to germination, fusion, concrescence, dilaceration, talons, cusps, dens in dente, etc. Protostylid, an additional cusp on the buccal aspect of the maxillary molar, which is a rare clinical finding, can lead to plaque accumulation, making oral hygiene maintenance difficult. This leads to clinical attachment loss and bone loss. This condition may often go undiagnosed. It should be diagnosed to prevent further complications. This case has been reported to make clinicians aware of the importance of diagnosing the case at the earliest possible time so that complications can be prevented and management is easier. From the perspective of forensic dentistry, this morphological feature, though uncommon, may be useful for the classification and identification of victims in mass causalities and bite marks on bodies or inanimate objects. This is one of the rarest cases of protostylids reported to date. This may not only pose a significant problem in endodontic therapy due to morphological alterations in root canals and periodontal therapy due to grove formation leading to an inability to maintain a plaque-free area (bone loss) but also be of very significant interest from the perspective of forensic dentistry.

5.
Lancet ; 403(10440): 1973-1974, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38763147
6.
RSC Adv ; 14(25): 17364-17379, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38813122

RESUMO

The investigation of binary and filled skutterudite structures, particularly PtSb3 and GdPt4Sb12, has gained significant attention, becoming a focal point in scientific research. This comprehensive report delves into the intrinsic characteristics of these structures using Density Functional Theory (DFT). Initially, we assess the structural stability of PtSb3 and GdPt4Sb12 by examining their total ground state energy and cohesive energy, employing the Brich Murnaghan equation of state to determine stability in various configurations. Further insights are gained by exploring second-order elastic constants (SOEC's) to extend our understanding of structural stability. The electronic structures are then meticulously defined through a quantum mechanical treatment, employing a combination of two distinct spin-polarized approximation schemes: Perdew-Burke-Ernzerhof Generalised Gradient Approximation (PBE-GGA) and Tran-Blaha modified Becke-Johnson (TB-mBJ). The resulting band structures reveal a symmetry in electronic behavior, showcasing spin-magnetic moments of 3 µB and 7.58 µB per formula unit, with the primary contributions emanating from the Pt 3d and Pt4+ 3d-transition elements. To gauge thermal stability, we evaluate the phonon-dependent Grüneisen parameter (γ) across specific temperature ranges. The study extends to exploring transport properties as a function of chemical potential (µ - EF) at various temperatures. The findings suggest that these designed materials hold substantial potential for diverse applications, particularly in conventional spin-based and thermoelectric technologies. The comprehensive insights obtained through this investigation pave the way for a deeper understanding and broader implications in various technological domains.

7.
Lancet ; 403(10435): 1435-1436, 2024 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615680
8.
EBioMedicine ; 103: 105093, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569318

RESUMO

BACKGROUND: Human restricted genes contribute to human specific traits in the immune system. CHRFAM7A, a uniquely human fusion gene, is a negative regulator of the α7 nicotinic acetylcholine receptor (α7 nAChR), the highest Ca2+ conductor of the ACh receptors implicated in innate immunity. Understanding the mechanism of how CHRFAM7A affects the immune system remains unexplored. METHODS: Two model systems are used, human induced pluripotent stem cells (iPSC) and human primary monocytes, to characterize α7 nAChR function, Ca2+ dynamics and decoders to elucidate the pathway from receptor to phenotype. FINDINGS: CHRFAM7A/α7 nAChR is identified as a hypomorphic receptor with mitigated Ca2+ influx and prolonged channel closed state. This shifts the Ca2+ reservoir from the extracellular space to the endoplasmic reticulum (ER) leading to Ca2+ dynamic changes. Ca2+ decoder small GTPase Rac1 is then activated, reorganizing the actin cytoskeleton. Observed actin mediated phenotypes include cellular adhesion, motility, phagocytosis and tissue mechanosensation. INTERPRETATION: CHRFAM7A introduces an additional, human specific, layer to Ca2+ regulation leading to an innate immune gain of function. Through the actin cytoskeleton it drives adaptation to the mechanical properties of the tissue environment leading to an ability to invade previously immune restricted niches. Human genetic diversity predicts profound translational significance as its understanding builds the foundation for successful treatments for infectious diseases, sepsis, and cancer metastasis. FUNDING: This work is supported in part by the Community Foundation for Greater Buffalo (Kinga Szigeti) and in part by NIH grant R01HL163168 (Yongho Bae).


Assuntos
Citoesqueleto de Actina , Sinalização do Cálcio , Células-Tronco Pluripotentes Induzidas , Receptor Nicotínico de Acetilcolina alfa7 , Humanos , Citoesqueleto de Actina/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Cálcio/metabolismo , Monócitos/metabolismo , Imunidade Inata , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Fagocitose
9.
Sci Rep ; 14(1): 8918, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637539

RESUMO

Here, we present systematic investigation of the structural and mechanical stability, electronic profile and thermophysical properties of f-electron based XNPO3 (X = Na, Cs, Ca, Ra) perovskites by first principles calculations. The structural optimization, tolerance factor criteria depicts the cubic structural stability of these alloys. Further, the stability of these materials is also determined by the cohesive and formation energy calculations along with mechanical stability criteria. The electronic structure is explored by calculating band structure and density of states which reveal the well-known half-metallic nature of the materials. Further, we have calculated different thermodynamic parameters including specific heat capacity, thermal expansion, Gruneisen parameter and their variation with temperature and pressure. The thermoelectric effectiveness of these materials is predicted in terms of Seebeck coefficient, electrical conductivity and power factor. All-inclusive we can say that calculated properties of these half-metallic materials extend their route in spintronics, thermoelectric and radioisotope generators device applications.

11.
Sci Rep ; 13(1): 22834, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129465

RESUMO

By using density functional theory, we have explored the structural, electro-mechanical, thermophysical and thermoelectric properties of CoZrSi and CoZrGe Heusler alloys. The ground state stability was determined by optimising the energy in various configurations like type I, II, and III. It was found that these alloys stabilized in the ferromagnetic phase in type I. We employed the Generalised Gradient Approximation and modified Becke-Johnson potentials to explore the electronic structure. The band structures of each of these Heusler alloys exhibit a half-metallic nature. Additionally, the computed second-order elastic parameters reveal their ductile nature of them. To understand the stability of the alloys at different pressures and temperatures, we investigated various thermodynamic parameters using the Quasi-Harmonic Debye model. We obtained the transport coefficients using the Boltzmann theory. Our findings indicate that these alloys can be used in spintronics and thermoelectric domains.

12.
ACS Omega ; 8(50): 48113-48129, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38144122

RESUMO

Through intricate calculations, the density functional theory (DFT) implemented in the Wien2k code was employed to comprehensively investigate a wide range of material characteristics. Our study encompasses an exhaustive analysis of structural stability, electronic properties, magnetic behaviors, transport phenomena, mechanical responses, and thermodynamic profiles of two notable instances of filled Skutterudites, namely, CeNi4P12 and DyCo4Sb12, which have been thoroughly explored. These computations were performed using the WIEN 2K code, combining local orbitals and the full-potential linearized augmented plane-wave approach. The findings provided insight into the wide range of properties of these materials. In this methodology, the exchange-correlation potential relies on the local-density approximation. We conducted the calculations with and without incorporating spin-orbit interactions. The results obtained provide information about the lattice constant, bulk modulus, and pressure derivative. The stability, as indicated by the P-V graphical plot, suggests that there are no structural phase transitions from the cubic symmetry structure. Notably, our work includes an examination of Curie temperatures, which are pivotal in understanding magnetic phase transitions. The validated elastic properties further support the material's stability and corroborate its ductile nature. These alloys should be considered for spintronic and thermoelectric applications due to their estimated transport characteristics and the observed ductile nature. To enhance our understanding of the thermal stability of antimony-based compounds, we have made reliable estimations of the thermophysical characteristics. By integrating theoretical insights with practical implications, we bridge the gap between fundamental understanding and material design applications. Using DFT in the Wien2k framework, we discover connections and patterns among different properties, showing how to create materials with specific functions and better performance. This approach not only advances our fundamental comprehension of materials but also promises innovation across various technological domains.

13.
Heliyon ; 9(11): e21594, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027865

RESUMO

Due to increased awareness regarding the health-promoting profile of millets, inclination towards their consumption has increased considerably. In the Himalayan region of India, cultivars of the two species of barnyard millet, namely Indian (Echinochloa frumentacea) and Japanese barnyard millet (E. esculenta), are grown. To compare the dehulled grain recovery, grain physical parameters, nutritional profile and antioxidant activity, an experiment was carried out at ICAR-VPKAS, Almora, Uttarakhand hills for two years using released and popular cultivars of Indian barnyard millet (VL 207 and VL 172) and Japanese barnyard millet (PRJ-1). The results indicated that the whole grain yield of Japanese barnyard millet cultivar PRJ-1 was significantly higher than Indian Barnyard millet cultivars VL 172 and VL 207; however, the dehulled grain recovery was considerably higher in VL 172 and VL 207 than PRJ-1. Similarly, the physical grain parameters were significantly higher in PRJ-1, but most dehulled grain parameters were at par in cultivars of both species. The nutritional estimation of dehulled grains of both species did not show remarkable differences for most traits. Still, crude fibre, Mn, and Zn were high in PRJ-1, while total digestible nutrients and phosphorous were high in VL 172 and VL 207. Dehulled grains exhibited much more crude protein, ash, minerals, and total digestible nutrients, but the husk accumulated significantly higher crude fibre and total polyphenols.

15.
RSC Adv ; 13(43): 29959-29974, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37842682

RESUMO

We conducted a comprehensive analysis of the fundamental properties of CoHfSi and CoHfGe half-Heusler alloys using density functional theory simulations implemented in Wien2k. To begin, structural optimization revealed that both alloys effectively adopt a cubic C1b structure, with Y1 as the dominant ferromagnetic phase. Electronic properties were computed using various approximation schemes, including the Generalized Gradient Approximation and the modified Becke-Johnson potential. The examination of electronic band structures and their accompanying density of states using the modified Becke-Johnson functional approach unveiled their half-metallic nature. In this context, the spin-up channel exhibited semiconductor behaviour, while the spin-down channel displayed metallic characteristics. Additionally, the spin-splitting observed in their resulting band structures contributed to a net magnetism within their lattice structure, making them promising candidates for spintronic applications. We also scrutinized Seebeck coefficients, electrical conductivity, thermal conductivity, and power factor to gain a better understanding of their thermoelectric properties.

17.
Sci Rep ; 13(1): 16882, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803067

RESUMO

Here, we investigated the structural, mechanical, electronic, magnetic, thermodynamic and thermoelectric properties of Strontium based simple perovskites SrMO3 (M = Pa, Np, Cm, Bk) by using density functional theory. First and foremost, the ground state stability of these perovskites was initially evaluated by optimizing their total ground state energies in distinct ferromagnetic and non-magnetic configurations. The structural stability in terms of their ground state energies defines that these alloys stabilize in ferromagnetic rather than competing non-magnetic phase. From the understandings of mechanical parameters these alloys are characterized to be ductile in nature. After that, two approximation schemes namely Generalized Gradient approximation and Tran-Blaha modified Becke-Johnson potential have been used to find their intimate electronic structures which displays the half-metallic nature of these alloys. Further, we have verified temperature and pressure effect on these alloys. Finally, the transport properties have been evaluated within the selected temperature range of 150-900 K. In view of this, the different transport parameters along with half-metallic nature advocate their possible applications in thermoelectric and spintronics devices.

18.
RSC Adv ; 13(40): 27873-27886, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37731830

RESUMO

Using the density functional theory methodology, we have thoroughly examined KRu4As12 and KRu4Sb12 skutterudites, including their structural, electronic, mechanical, transport, and thermodynamic properties. First and foremost, using the Birch-Murnaghan equation of state, the structural stability has been calculated in terms of their total ground state and cohesive energies. With the use of the approximation approaches GGA and GGA + mBJ, the electrical structure and density of the states reveal their metallic nature. This demonstration predicts the dominant ferromagnetic spin configuration of materials by considering their electronic behavior and magnetic interactions. The ductile behavior of these alloys is also addressed by their mechanical qualities, which indicate how they might be used in engineering and industrial settings. Moreover, the semi-classical Boltzmann transport theory has been employed to examine the Seebeck coefficient as well as the electric and thermal conductivities. The general tendency of these compounds demonstrates their various potential uses as electrode materials. The quasi-harmonic Debye approximation is a method used to analyze the stability of a system under high pressures and accounts for the temperature dependency of thermodynamics. It combines the quasi-harmonic approximation, which considers the anharmonicity of vibrations, with the Debye model, which describes the vibrational modes of a solid. This approach allows for a more accurate representation of the system's behavior at different temperatures and pressures. By implementing this approximation, researchers can gain insights into the stability and thermodynamic properties of materials under extreme conditions.

19.
Sci Rep ; 13(1): 12795, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550338

RESUMO

The structural stability, optoelectronic and magnetic characteristics of K2NaMI6 (M = Mn, Co, and Ni) halide double perovskites have been demonstrated to be explained using density functional theory computations. The prominent generalized gradient approximation and integration of the mBJ potential are implemented to estimate the exchange-correlation potential, which is the only unidentified parameter in the state-of-the-art formulism. The structural optimization, mechanical stability criteria, and tolerance factor demonstrate the reliability of the double perovskites in a cubic structure with Fm3m symmetry. The elastic constants facilitated mechanical stability and revealed the brittle nature of these double perovskites. The spin-polarized electronic band profile and the behaviour of the dielectric constant and absorption coefficient in the spin-up and down channels show the presence of half-metallic nature in these materials. Additionally, we examined magnetism and the genesis of the half-metallic gap in this article. The half-metallic and magnetic properties are attributed to the unpaired electrons in the split d-orbitals of the M-sited elements in the crystal field. The Mn-, Co-, and Ni-based double perovskites were found to possess total magnetic moments of 4 µB, 4 µB, and 1 µB, respectively, with the transition metal atoms comprising up the majority of this magnetic moment. The Fermi level's perfect spin polarisation promotes the potential application of double perovskites in spintronic technology.

20.
Lancet ; 402(10396): 94, 2023 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-37423220
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