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1.
Math Biosci ; 372: 109190, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38631561

RESUMO

This paper proposes a bidimensional modeling framework for Wolbachia invasion, assuming imperfect maternal transmission, incomplete cytoplasmic incompatibility, and direct infection loss due to thermal stress. Our model adapts to various Wolbachia strains and retains all properties of higher-dimensional models. The conditions for the durable coexistence of Wolbachia-carrying and wild mosquitoes are expressed using the model's parameters in a compact closed form. When the Wolbachia bacterium is locally established, the size of the remanent wild population can be assessed by a direct formula derived from the model. The model was tested for four Wolbachia strains undergoing laboratory and field trials to control mosquito-borne diseases: wMel, wMelPop, wAlbB, and wAu. As all these bacterial strains affect the individual fitness of mosquito hosts differently and exhibit different levels of resistance to temperature variations, the model helped to conclude that: (1) the wMel strain spreads faster in wild mosquito populations; (2) the wMelPop exhibits lower resilience but also guarantees the smallest size of the remanent wild population; (3) the wAlbB strain performs better at higher ambient temperatures than others; (4) the wAu strain is not sustainable and cannot persist in the wild mosquito population despite its resistance to high temperatures.


Assuntos
Mosquitos Vetores , Wolbachia , Wolbachia/fisiologia , Wolbachia/patogenicidade , Animais , Mosquitos Vetores/microbiologia , Culicidae/microbiologia , Modelos Biológicos , Conceitos Matemáticos
2.
Protein J ; 43(3): 487-502, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38453735

RESUMO

The present study aims at understanding the effect of organic solvents on the specific proteolytic activity and operational stability of asclepain cI in aqueous-organic media, using correlations between geometrical and structural parameters of asclepain cI. These correlations were determined by molecular dynamics (MD) simulations and the secondary structure of the enzyme validated by Fourier-transform Infrared (FTIR) spectroscopy. Asclepain cI exhibited significantly higher catalytic potential in 29 of the 42 aqueous-organic media tested, composed by 0.1 mM TRIS hydrochloride buffer pH 8 (TCB) and an organic solvent, than in buffer alone. Asclepain cI in water-organic miscible systems showed high FTIR spectral similarity with that obtained in TCB, while in immiscible systems the enzyme acquired different secondary structures than in buffer. Among the conditions studied, asclepain cI showed the highest catalytic potential in 50% v/v ethyl acetate in TCB. According to MD simulations, that medium elicited solvation and flexibility changes around the active center of asclepain cI and conducted to a new secondary structure with the active center preserved. These results provide valuable insights into the elucidation of the molecular mechanism of asclepain cI tolerance to organic solvents and pave the way for its future application for the synthesis of peptides in aqueous-organic media.


Assuntos
Simulação de Dinâmica Molecular , Estrutura Secundária de Proteína , Solventes , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Estabilidade Enzimática
3.
Int Arch Otorhinolaryngol ; 28(1): e107-e114, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38322445

RESUMO

Introduction Cochlear implantation has been considered as the best treatment in patients with severe to profound hearing loss unaidable with hearing aids. The main value of endoscope-assisted cochlear implantation is improved visibility of the RW Objective to assess the value of endoscopic assisted CI surgery via facial recess approach without elevating tympanic anulus. Methods This Prospective case series study non-randomized sample was performed on 50 patients with severe to profound hearing loss unaidable with hearing aids undergoing unilateral endoscopic assisted cochlear implant surgery with round window electrode insertion Results There were 23 male and 27 female patients. Most of the cases were children (41 cases). Of those 50 patients, 39 were prelingually hearing impaired. Four cases had various inner ear abnormalities. The standard mastoidectomy and Posterior Tympanotomy approach were used for all cases. Endoscopic identification of the RW through the PT enabled us to perform regular surgery in all cases. The current study concludes the difference between microscopic exposure and endoscopic exposure represented by Saint Tomas classification found that endoscopic exposure of round window classification is better represented by downgrading in the classification of round window exposure as type I 29(58%), type IIa 18(36%) type IIb 3 (6%) Non were type III by endoscopic exposure compared to microscopic exposure of round window is a type I 7(14%), type II 14(28%), type IIb 22(44%) and type III 7 (14%). Conclusion Endoscopy proved a great value in exposure and identification of RW in CI surgery through posterior tympanotomy approach.

4.
J Biol Chem ; 300(3): 105700, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307383

RESUMO

Selective retrograde transport from endosomes back to the trans-Golgi network (TGN) is important for maintaining protein homeostasis, recycling receptors, and returning molecules that were transported to the wrong compartments. Two important transmembrane proteins directed to this pathway are the Cation-Independent Mannose-6-phosphate receptor (CI-MPR) and the ATP7B copper transporter. Among CI-MPR functions is the delivery of acid hydrolases to lysosomes, while ATP7B facilitates the transport of cytosolic copper ions into organelles or the extracellular space. Precise subcellular localization of CI-MPR and ATP7B is essential for the proper functioning of these proteins. This study shows that both CI-MPR and ATP7B interact with a variant of the clathrin adaptor 1 (AP-1) complex that contains a specific isoform of the γ-adaptin subunit called γ2. Through synchronized anterograde trafficking and cell-surface uptake assays, we demonstrated that AP-1γ2 is dispensable for ATP7B and CI-MPR exit from the TGN while being critically required for ATP7B and CI-MPR retrieval from endosomes to the TGN. Moreover, AP-1γ2 depletion leads to the retention of endocytosed CI-MPR in endosomes enriched in retromer complex subunits. These data underscore the importance of AP-1γ2 as a key component in the sorting and trafficking machinery of CI-MPR and ATP7B, highlighting its essential role in the transport of proteins from endosomes.


Assuntos
Complexo 1 de Proteínas Adaptadoras , ATPases Transportadoras de Cobre , Endossomos , Transporte Proteico , Receptor IGF Tipo 2 , Rede trans-Golgi , Humanos , Endossomos/metabolismo , Células HeLa , Transporte Proteico/genética , Receptor IGF Tipo 2/genética , Receptor IGF Tipo 2/metabolismo , Rede trans-Golgi/genética , Rede trans-Golgi/metabolismo , ATPases Transportadoras de Cobre/genética , ATPases Transportadoras de Cobre/metabolismo , Complexo 1 de Proteínas Adaptadoras/genética , Complexo 1 de Proteínas Adaptadoras/metabolismo , Subunidades gama do Complexo de Proteínas Adaptadoras/metabolismo
5.
Int. arch. otorhinolaryngol. (Impr.) ; 28(1): 107-114, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1557999

RESUMO

Abstract Introduction Cochlear implantation has been considered as the best treatment in patients with severe to profound hearing loss unaidable with hearing aids. The main value of endoscope-assisted cochlear implantation is improved visibility of the RW Objective to assess the value of endoscopic assisted CI surgery via facial recess approach without elevating tympanic anulus. Methods This Prospective case series study non-randomized sample was performed on 50 patients with severe to profound hearing loss unaidable with hearing aids undergoing unilateral endoscopic assisted cochlear implant surgery with round window electrode insertion Results There were 23 male and 27 female patients. Most of the cases were children (41 cases). Of those 50 patients, 39 were prelingually hearing impaired. Fourcases had various inner ear abnormalities. The standard mastoidectomy and Posterior Tympanotomy approach were used for all cases. Endoscopic identification of the RW through the PT enabled us to perform regular surgery in all cases. The current study concludes the difference between microscopic exposure and endoscopic exposure represented by Saint Tomas classification found that endoscopic exposure of round window classification is better represented by downgrading in the classification of round window exposure as type I 29(58%), type IIa 18(36%) type IIb 3 (6%) Non were type III by endoscopic exposure compared to microscopic exposure of round window is a type I 7 (14%), type II 14(28%), type IIb 22(44%) and type III 7 (14%). Conclusion Endoscopy proved a great value in exposure and identification of RW in CI surgery through posterior tympanotomy approach,

6.
Plant Biol (Stuttg) ; 25(5): 740-749, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37158679

RESUMO

Aluminium (Al) is toxic to most plants. Nevertheless, some species accumulate Al without showing toxicity symptoms. Previous studies have evidenced Al in chloroplasts of Al-accumulating species from the Cerrado vegetation in South America. We ask whether Al increases carbon assimilation through enhanced apparent efficiency of Rubisco. Seedlings of the Al-accumulator Qualea grandiflora (Vochysiaceae) were grown in nutrient solution with 0, 740, and 1480 µm Al. Growth parameters, relative leaf water content, Al concentration in organs, gas exchange and apparent carboxylation efficiency (measured from A/Ci curves) were evaluated for 60 days. Plants without Al showed no root growth, necrotic roots, low gas exchange rates, and decreased apparent carboxylation efficiency. Al-treated plants, however, showed new white roots and increased root biomass leading to higher leaf hydration, and apparent carboxylation efficiency was higher in these plants. Increased Al available in the nutrient solution increased Al accumulation in plant organs. Absence of Al compromised root integrity in Q. grandiflora, thus limiting leaf hydration. No positive direct effect of Al on Rubisco was evidenced in Al-treated plants.


Assuntos
Alumínio , Myrtales , Alumínio/toxicidade , Ribulose-Bifosfato Carboxilase , Plantas , Plântula , Folhas de Planta , Raízes de Plantas
8.
Nanomaterials (Basel) ; 13(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36770395

RESUMO

The development of nanomaterials has drawn considerable attention in nanomedicine to advance cancer diagnosis and treatment over the last decades. Gold nanorods (GNRs) and magnetic nanoparticles (MNPs) have been known as commonly used nanostructures in biomedical applications due to their attractive optical properties and superparamagnetic (SP) behaviors, respectively. In this study, we proposed a simple combination of plasmonic and SP properties into hybrid NPs of citrate-coated manganese ferrite (Ci-MnFe2O4) and cetyltrimethylammonium bromide-coated GNRs (CTAB-GNRs). In this regard, two different samples were prepared: the first was composed of Ci-MnFe2O4 (0.4 wt%), and the second contained hybrid NPs of Ci-MnFe2O4 (0.4 wt%) and CTAB-GNRs (0.04 wt%). Characterization measurements such as UV-Visible spectroscopy and transmission electron microscopy (TEM) revealed electrostatic interactions caused by the opposing surface charges of hybrid NPs, which resulted in the formation of small nanoclusters. The performance of the two samples was investigated using magneto-motive ultrasound imaging (MMUS). The sample containing Ci-MnFe2O4_CTAB-GNRs demonstrated a displacement nearly two-fold greater than just using Ci-MnFe2O4; therefore, enhancing MMUS image contrast. Furthermore, the preliminary potential of these hybrid NPs was also examined in magnetic hyperthermia (MH) and photoacoustic imaging (PAI) modalities. Lastly, these hybrid NPs demonstrated high stability and an absence of aggregation in water and phosphate buffer solution (PBS) medium. Thus, Ci-MnFe2O4_CTAB-GNRs hybrid NPs can be considered as a potential contrast agent in MMUS and PAI and a heat generator in MH.

9.
Methods Mol Biol ; 2617: 17-30, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656514

RESUMO

The temperature-inducible λpL/pR-cI857 expression system has been widely used to produce recombinant proteins (RPs), especially when it is necessary to avoid the addition of exogenous materials to induce the expression of recombinant genes, preventing contamination of bioprocesses. The temperature increase favors the formation of inclusion bodies (IBs). The temperature upshift could change the metabolism, productivities, cell viability, IBs architecture, and the host cell proteins inside IBs, affecting downstream to obtain the final product. In this contribution, we focus on the relationship between the bioprocesses using temperature increase as inducer, the heat shock response associated with temperature up-shift, the RP accumulation, and the formation of IBs. Here, we describe how to produce IBs and how culture conditions can modulate the composition and architecture of IBs by modifying the induction temperature in RP production.


Assuntos
Escherichia coli , Corpos de Inclusão , Proteínas Recombinantes , Escherichia coli/genética , Escherichia coli/metabolismo , Corpos de Inclusão/metabolismo , Proteínas Recombinantes/biossíntese , Temperatura
10.
Artigo em Inglês | MEDLINE | ID: mdl-36502482

RESUMO

Because of their adaptability and user-friendliness, internal combustion engines are widely used for a variety of purposes, including the generation of consistent power as well as transportation. As a result, the question of whether or not these engines can make use of bio-oils is an important one today. Bio-oils derived from biomass pyrolysis differ significantly from those derived from petroleum-based fuels and biodiesel. They could, however, be valuable alternatives to fossil fuels in order to attain a carbon-neutral future. Bio-oil obtained from catalytic pyrolysis of Argemone Mexicana seed using titanium oxide (TiO2) nanoparticles was employed in IC engine to check its suitability as an alternative fuel. Engine performance analysis was conducted at B5, B10, B15, B20, B25, and B30 blend for different parameters such as brake thermal efficiency, exhaust gas temperature, and brake-specific fuel consumption with change in engine load. Emission analysis was also carried out for carbon monoxide, hydrocarbon, nitrogen oxides, and carbon dioxide emissions. It was found that B30 blend resembled best performance and the bio-oil produced from catalytic pyrolysis of Argemone mexicana seed can be utilised as a substitute of fossil fuels in IC engine.

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