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1.
Afr J Lab Med ; 13(1): 2375, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39228902

RESUMO

Background: The clinical presentations of coronavirus disease 2019 (COVID-19) exhibit significant variation, ranging from asymptomatic cases to mortality resulting from severe pneumonia. Host genetics can partially explain this variation. Objective: This study evaluated possible associations between severity and outcome of COVID-19 and single nucleotide polymorphism (SNP) rs2285666 in the ACE2 gene and SNP rs2070788 in the TMPRSS2 gene. Methods: The study included a sample of 100 consecutive adult patients admitted to the COVID-19 Isolation and Intensive Care Units of the Zagazig University Hospitals, Zagazig, Egypt from July 2021 to November 2021. For rs2285666, polymerase chain reaction-restriction fragment length polymorphism was carried out. For rs2070788, real-time polymerase chain reaction was performed. Results: For rs2285666, the GA genotype was the most frequent among female patients (39% [16/41]) and the A genotype was more prevalent among male patients (54.2% [32/59]). For rs2070788, the AA genotype was the most frequent among all patients (46% [46/100]). No rs2285666 or rs2070788 genotypes or allele frequencies had significant associations with either severity or outcomes of patients. Conclusion: This study found no significant associations of COVID-19 severity or outcomes of patients with genotypes or allele frequencies of the rs2285666 SNP in the ACE2 gene or the rs2070788 SNP of the TMPRSS2 gene. The search for other genetic associations with COVID-19 infection is still required. What this study adds: The study reveals that host genetics explain the variation observed in the disease. Specific genetic variants can confer either increased susceptibility or resistance to the disease.

2.
Explor Drug Sci ; 2(3): 322-338, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39118806

RESUMO

Aim: This study was aimed at finding the binding site on the human E-cadherin for Ala-Asp-Thr Cyclic 5 (ADTC5), ADTC7, and ADTC9 peptides as blood-brain barrier modulator (BBBM) for determining their mechanism of action in modulating the blood-brain barrier (BBB). Methods: ADTC7 and ADTC9 were derivatives of ADTC5 where the Val6 residue in ADTC5 was replaced by Glu6 and Tyr6 residues, respectively. The binding properties of ADTC5, ADTC7, and ADTC9 to the extracellular-1 (EC1) domain of E-cadherin were evaluated using chemical shift perturbation (CSP) method in the two dimensional (2D) 1H-15N-heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR) spectroscopy. Molecular docking experiments were used to determine the binding sites of these peptides to the EC1 domain of E-cadherin. Results: This study indicates that ADTC5 has the highest binding affinity to the EC1 domain of E-cadherin compared to ADTC7 and ADTC9, suggesting the importance of the Val6 residue as shown in our previous in vitro study. All three peptides have a similar binding site at the hydrophobic binding pocket where the domain swapping occurs. ADTC5 has a higher overlapping binding site with ADTC7 than that of ADTC9. Binding of ADTC5 on the EC1 domain influences the conformation of the EC1 C-terminal tail. Conclusions: These peptides bind the domain swapping region of the EC1 domain to inhibit the trans-cadherin interaction that creates intercellular junction modulation to increase the BBB paracellular porosity.

3.
Cureus ; 16(6): e62316, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39006625

RESUMO

Technetium-99m pyrophosphate (Tc-99m PYP) cardiac imaging is a simple, widely available, noninvasive method to identify patients with transthyretin-type cardiac amyloidosis (ATTR), and it has remarkably high diagnostic accuracy with very high sensitivity and specificity. Visual scores of 0, 1, 2, and 3 indicate non-myocardial uptake, uptake less than rib, equal to rib, and greater than rib uptake, respectively. Semiquantitative assessment using the heart-to-contralateral lung ratio of more than 1.5 at 1 hour accurately distinguishes ATTR from the cardiac amyloid light chain subtype. However, there are several incidental non-cardiac findings that can be seen in planar images, rotating single-photon emission computed tomography (SPECT) images, maximum intensity projection images, or computed tomography images acquired for attenuation correction. These findings may lead to the early detection of a noncardiac condition that may require additional treatment. The intent of this review is to demonstrate several incidental noncardiac abnormalities that have an impact on patient management and follow-up.

4.
J Phys Chem Lett ; 15(21): 5689-5695, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38767955

RESUMO

Lead-chloride perovskites are promising candidates for optoelectronic applications, such as visible-blind UV photodetection. It remains unclear how the deep defects in this wide-bandgap material impact the carrier recombination dynamics. In this work, we study the defect properties of MAPbCl3 (MA = CH3NH3) based on photoluminescence (PL) measurements. Our investigations show that apart from the intrinsic emission, four sub-bandgap emissions emerge, which are very likely to originate from the radiative recombination of excitons bound to several intrinsic vacancy and interstitial defects. The intensity of various emission features can be tuned by adjusting the type and ratio of precursors used during synthesis. Our study not only provides important insights into the defect property and carrier recombination mechanism in this class of material but also demonstrates efficient strategies for defect passivation and engineering, paving the way for further development of lead-chloride perovskite-based optoelectronic devices.

5.
Bioresour Bioprocess ; 11(1): 36, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38647805

RESUMO

Cell separation using microfluidics has become an effective method to isolate biological contaminants from bodily fluids and cell cultures, such as isolating bacteria contaminants from microalgae cultures and isolating bacteria contaminants from white blood cells. In this study, bacterial cells were used as a model contaminant in microalgae culture in a passive microfluidics device, which relies on hydrodynamic forces to demonstrate the separation of microalgae from bacteria contaminants in U and W-shaped cross-section spiral microchannel fabricated by defocusing CO2 laser ablation. At a flow rate of 0.7 ml/min in the presence of glycine as bacteria chemoattractant, the spiral microfluidics devices with U and W-shaped cross-sections were able to isolate microalgae (Desmodesmus sp.) from bacteria (E. coli) with a high separation efficiency of 92% and 96% respectively. At the same flow rate, in the absence of glycine, the separation efficiency of microalgae for U- and W-shaped cross-sections was 91% and 96%, respectively. It was found that the spiral microchannel device with a W-shaped cross-section with a barrier in the center of the channel showed significantly higher separation efficiency. Spiral microchannel chips with U- or W-shaped cross-sections were easy to fabricate and exhibited high throughput. With these advantages, these devices could be widely applicable to other cell separation applications, such as separating circulating tumor cells from blood.

6.
Saudi Pharm J ; 32(4): 101986, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38487020

RESUMO

Concerns about the social and economic collapse, high mortality rates, and stress on the healthcare system are developing due to the coronavirus onslaught in the form of various species and their variants. In the recent past, infections brought on by coronaviruses severe acute respiratory syndrome coronaviruses (SARS-CoV and SARS-CoV-2) as well as middle east respiratory syndrome coronavirus (MERS-CoV) have been reported. There is a severe lack of medications to treat various coronavirus types including MERS-CoV which is hazard to public health due to its ability for pandemic spread by human-to-human transmission. Here, we utilized sinapic acid (SA) against papain-like protease (PLpro), a crucial enzyme involved in MERS-CoV replication, because phytomedicine derived from nature has less well-known negative effects. The thermal shift assay (TSA) was used in the current study to determine whether the drug interact with the recombinant MERS-CoV PLpro. Also, inhibition assay was conducted as the hydrolysis of fluorogenic peptide from the Z-RLRGG-AMC-peptide bond in the presence of SA to determine the level of inhibition of the MERS-CoV PLpro. To study the structural binding efficiency Autodock Vina was used to dock SA to the MERS-CoV PLpro and results were analyzed using PyMOL and Maestro Schrödinger programs. Our results show a convincing interaction between SA and the MERS protease, as SA reduced MERS-CoV PLpro in a dose-dependent way IC50 values of 68.58 µM (of SA). The TSA showed SA raised temperature of melting to 54.61 °C near IC50 and at approximately 2X IC50 concentration (111.5 µM) the Tm for SA + MERS-CoV PLpro was 59.72 °C. SA was docked to MERS-CoV PLpro to identify the binding site. SA bound to the blocking loop (BL2) region of MERS-CoV PLpro interacts with F268, E272, V275, and P249 residues of MERS-CoV PLpro. The effectiveness of protease inhibitors against MERS-CoV has been established and SA is already known for broad range biological activity including antiviral properties; it can be a suitable candidate for anti-MERS-CoV treatment.

7.
Pharmaceutics ; 16(2)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38399350

RESUMO

The journal retracts the article, "Thymoquinone-Loaded Soy-Phospholipid-Based Phytosomes Exhibit Anticancer Potential against Human Lung Cancer Cells" [...].

8.
Appl Immunohistochem Mol Morphol ; 32(2): 102-110, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37982568

RESUMO

BACKGROUND: It will be important to understand the molecular pathways of gastric cancer (GC) occurrence and progression, thus detecting predictive and prognostic biomarkers of GC. Pyrroline-5-carboxylate reductase 1 (PYCR1) was upregulated in many cancers, suggesting its possible roles in carcinogenesis and tumor metastases. Barrier-of-autointegration factor 1 (BANF1) is a protein family that plays essential roles in maintaining the integrity of an intact cellular genome. Rho-GTPs are molecular switches that control many signal transduction pathways in normal cells, including 3 subgroups from 1 to 3 (DLC1-3). DLC-3, known as StAR-related lipid transfer domain protein 8 (STARD8), and its role in cancers were not sufficiently studied. The study aimed to investigate the significance of PYCR1, BANF1, and STARD8 protein expression in GC tissues and normal gastric mucosa retrieved from patients with GC to detect prognostic roles of expression. PATIENTS AND METHODS: Specimens were collected from 100 patients with gastric carcinoma. After the application of the inclusion criteria of the study, we prepared 100 paraffin blocks from samples of the 100 included patients; each block included samples from gastric carcinoma and adjacent non-neoplastic gastric mucosa. We assessed the expression of PYCR1, BANF1, and STARD8 using immunohistochemistry in all studied samples. We followed patients for the detection of disease progression and survival rates. We correlate PYCR1, BANF1, and STARD8 expression with clinical, pathologic, and prognostic parameters. RESULTS: Overexpression of PYCR1 and BANF1 and decreased expression of STARD8 was found in gastric carcinoma tissues than adjacent non-neoplastic gastric mucosa ( P <0.001), and was positively associated with high grade ( P =0.006), depth of tumor invasion, presence of lymph nodes metastases and advanced stage ( P =0.001), high incidence of GC progression, recurrence, unfavorable disease-free survival ( P =0.003) and unfavorable overall survival rates ( P <0.001). Thus, it was revealed that; in univariate and multivariate analyses, levels of PYCR1, BANF1, and STARD8 are associated with the overall survival rate of GC patients. CONCLUSIONS: We showed that overexpression of PYCR1 and BANF1 and decreased expression of STARD8 in GC tissues was associated with poor prognosis and GC progression.


Assuntos
Carcinoma , Neoplasias Gástricas , Humanos , Biomarcadores Tumorais/metabolismo , Intervalo Livre de Doença , Proteínas Ativadoras de GTPase , Prognóstico , Neoplasias Gástricas/metabolismo , Proteínas Supressoras de Tumor
9.
Curr Probl Cardiol ; 49(1 Pt C): 102130, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37858847

RESUMO

BACKGROUND: Recent advances in the treatment of breast cancer have resulted in improved overall cancer survival; however, cancer therapy related cardiac dysfunction is considered a major adverse effect of several chemotherapeutic agents, particularly anthracyclines. Hence, there is a need to develop proper cardioprotective strategies to limit myocardial injury following chemotherapy. OBJECTIVE: To evaluate the effect of statin therapy on prevention of anthracycline- induced cardiotoxicity in female patients with breast cancer. PATIENTS AND METHODS: The current study is a prospective, randomized, single-blind, placebo-controlled trial in which we enrolled a total of 110 female patients with newly diagnosed breast cancer who received anthracycline based chemotherapy. Patients were randomly assigned in 1:1 ratio into two groups, study group in which patients received 40 mg of oral atorvastatin and control group in which patients received placebo. A comprehensive echocardiographic examination was performed to all patients prior to receiving the chemotherapy and after 6 months, assessment of LV ejection fraction was done by 3D-echocardiography. All echocardiographers were blinded to all the patients' characteristics and assignment to either group. RESULTS: The mean age of patients assigned to the control group was 49.8±10.51 years old, while patients assigned to the intervention group had mean age of 47.84± 9.16 years old, both the control group and the intervention group were similar in demographic data and baseline clinical characteristics. There was a highly significant difference between the two groups regarding both the absolute LVEF assessed by 3D- echocardiography at 6 months and the percentage of change compared to baseline values, patients assigned to the control group had mean LVEF of 52.92% at 6 months with percentage of change reaching -7.06%, while those assigned to the intervention group had mean LVEF reaching 56.22% at 6 months with a percentage of change reaching -3.64% (P-value: 0.008 and 0.004 for the absolute value and percentage of change respectively). There was a significant difference between the two groups regarding incidence of development of cancer therapy related cardiac dysfunction (CTRCD); defined as drop in LVEF more than 10% and to a value below 53% assessed by 3D echocardiography, among the control group 15 patients (30%) developed CTRCD after 6 months from starting Anthracyclines based chemotherapy, while, among the intervention group only 6 patients (12%) developed CTRCD. (P-value= 0.027) CONCLUSION: Prophylactic use of atorvastatin may prevent the development of cancer therapy related cardiac dysfunction in breast cancer patients receiving anthracycline based chemotherapy.


Assuntos
Neoplasias da Mama , Cardiopatias , Inibidores de Hidroximetilglutaril-CoA Redutases , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Antraciclinas/efeitos adversos , Antibióticos Antineoplásicos/efeitos adversos , Atorvastatina/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Ecocardiografia/métodos , Cardiopatias/induzido quimicamente , Cardiopatias/diagnóstico por imagem , Cardiopatias/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Estudos Prospectivos , Método Simples-Cego , Volume Sistólico , Função Ventricular Esquerda
10.
Heliyon ; 9(11): e21998, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38045190

RESUMO

This research article examines the reaction-diffusion process in an immobilized enzyme batch reactor. The model incorporates strongly non-linear factors that are associated with standard Michaelis-Menten kinetics. The non-linear reaction-diffusion equations for substrate and product concentrations have been approximated analytically. Employing two different semi-analytical methods, Akbari-Ganji's method (AGM) and the modified Adomian decomposition method (MADM), to compute the dimensionless steady-state solutions to the system of non-linear differential equations for all values of reaction parameters. In addition, the dynamics of the mean integrated effectiveness factor of penicillin acylase in porous spherical particles have been presented for the determination of the local effectiveness factor. In order to gauge the potency of our proposed solution, we compare two semi-analytical results with a numerical result that are in good agreement across the whole concentration range. The proposed formulation aims to simulate the dynamic performance of the system utilizing the parameters and would enhance the determination of the optimum particle size for enzyme catalysts.

11.
J Appl Genet ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38085436

RESUMO

Prostate-specific membrane antigen (PSMA) is a protein frequently found to be overexpressed in various non-prostate cancer types. Our investigation, based on data from the TCGA databases, revealed a wide range of differential PSMA (encoded by FOLH1 gene) mRNA expressions across several cancer types, with notable findings in triple-negative breast carcinoma. This preclinical study delves into the molecular underpinnings of utilizing PSMA-targeting radiopharmaceuticals within specific breast cancer subtypes. We conducted a transcriptomic expression analysis of PSMA across different subtypes of breast cancer, focusing particularly on the triple-negative breast cancer (TNBC) subset. Our analysis encompassed 1100 patients from The Cancer Genome Atlas dataset. We observed a broad distribution of PSMA mRNA expressions across various subgroups within these cancer types. Notably, a subset of triple-negative breast cancer exhibited higher PSMA mRNA expression compared to non-triple-negative breast cancer. Intriguingly, we found that higher PSMA mRNA expression was associated with favorable outcomes in terms of distant metastasis-free and relapse-free survival in patients. Within a subset of TNBC patients, there is a prevalent overexpression of PSMA, which appears to be linked with improved relapse-free and distant metastasis-free survival. Our study succinctly highlights the significance of PSMA overexpression in TNBC and its potential impact on patient outcomes and provides a clear and concise overview of the study's contributions to breast cancer research.

12.
Int J Pharm ; 648: 123593, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37956722

RESUMO

Based on our previous report, the study was extended to investigate the impact of miconazole nitrate (MCN) loaded cationic/anionic nanoemulsions and nanoemulsion gels on permeation behaviour across artificial-membrane, EpiDerm, and rat skin. Nanoemulsions and gels were evaluated for size, charge, viscosity, size-distribution, pH, and percent entrapment efficiency (%EE). In vitro drug diffusion across artificial membrane and EpiDerm were conducted to get diffusion coefficients. Permeation profiles were studied using rat skin to investigate mechanistic insight of formulated mediated permeation followed by CLSM (confocal laser scanning microscopy), SEM (scanning electron microscopy), AFM (atomic force microscopy), and irritation studies. Results showed that MCNE11-Rh (probed cationic nanoemulsion at pH âˆ¼ 7.2) and MNE11-Rh (probed anionic nanoemulsion at pH âˆ¼ 7.2) showed size values of 158 nm and 145 nm, respectively whereas MCNE11-GR (probed cationic nanoemulsion gel at pH âˆ¼ 6.8) and MNE11-GR (probed anionic nanoemulsion gel at pH âˆ¼ 6.8) exhibited size values 257 nm and 243 nm, respectively. The %EE values were found to be as 91.5 % and 89.6 % for MCNE11-Rh and MNE11-Rh, respectively. The gels (∼6000 cP) elicited relatively high viscosity than nanoemulsions (∼3300 - 3500 cP). MCNE11-GR showed the highest values of permeation flux, diffusion rate, diffusion coefficient (D), and permeation coefficient (P) across artificial membrane, EpiDerm, and rat skin which may be attributed to three potential factors (cationic charge, composition, and hydration by the hydrophilic gel) working in tandem. Transepidermal water loss (TEWL) by the MCNE11-GR was maximum (14.4 g/m2h) than control (6.1 g/m2h) indicating augmented interaction of MCNE11-Rh with skin components. Conclusively, cationic nanoemulsion gel was promising carrier for enhanced permeation and the drug access to the dermal region to treat deep seated fungal infections.


Assuntos
Membranas Artificiais , Miconazol , Ratos , Animais , Administração Cutânea , Pele , Géis/química , Emulsões/química , Tamanho da Partícula
13.
ACS Omega ; 8(44): 41755-41764, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37970055

RESUMO

A nanoemulsion-based polyherbal mouthwash (PHFX) of Curcuma longa hydroalcoholic extract was developed and evaluated for its antibacterial effects against a variety of Gram-positive and Gram-negative oral pathogens in comparison to standard chlorhexidine acetate (CHD-A) (positive control). Various nanoemulsion-based mouthwashes of C. longa extract were produced using an aqueous phase titration approach via construction of pseudoternary phase diagrams. The developed nanoemulsion-based PHFX was studied for thermodynamic stability tests. Selected formulations (PHFX1-PHFX5) were characterized physicochemically for droplet diameter, polydispersity index (PDI), refractive index (RI), transmittance, and pH. The drug release studies were performed using the dialysis method. Based on the minimum droplet diameter (26.34 nm), least PDI (0.132), optimal RI (1.337), maximum %T (99.13), optimal pH (6.45), and maximum cumulative drug release (98.2%), formulation PHFX1 (containing 0.5% w/w of C. longa extract, 1.5% w/w of clove oil, 7.0% w/w of Tween-80, 7.0% w/w of Transcutol-HP, and 84.0% w/w of water) was selected for antimicrobial studies in comparison to standard CHD-A. The antibacterial effects and minimum inhibitory concentration were studied against various Gram-positive oral pathogens such as Streptococcus mutans, Staphylococcus aureus, Streptococcus pneumoniae, and Bacillus subtilis and Gram-negative oral pathogens such as Escherichia coli and Klebsiella pneumoniae. The antibacterial effects of PHFX1 were found to be significant over standard CHD-A against most Gram-positive and Gram-negative oral pathogens. The antimicrobial studies showed that the formulation PHFX1 was effective against all oral pathogens even at 3- to 4-fold lower working concentrations. These findings indicated the potential of nanoemulsion-based mouthwash in the treatment of a variety of oral pathogen infections.

14.
BMC Ophthalmol ; 23(1): 462, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974078

RESUMO

BACKGROUND: V pattern identification is essential for proper strabismus management. Graded recession is a tailored approach to treat inferior oblique overaction (IOOA). The aim is to evaluate the efficacy of graded recession of inferior oblique muscle for correction of different grades of V pattern. METHODS: Forty patients from 3 to 18 years old with V pattern strabismus and primary IOOA were evaluated by prism cover test to assess the grade of IOOA and amplitude of V-pattern. Graded recession of IO muscle depends on the amplitude of the V-pattern and degree of IOOA. Eight mm recession for amplitude 15 PD to 20 PD and mild IOOA (10 PD-15 PD or + 1) ,10 mm recession for amplitude 20-30 PD and moderate IOOA (15-25 PD or + 2) and maximum recession for amplitude more than 30 PD and marked IOOA (≥ 25 PD or + 3). Simultaneous correction of the horizontal deviation was performed. Follow up after I week,1 month ,3 month and 6-month. Trial Registration Number (TRN) (NCT05786053) on 23/3/2023. RESULTS: The mean age of the study patients was 9 ± 4.261. Twenty patients (50%) had V-pattern esotropia, 12 (30%) exotropia, 4 (10%) orthotropic and four (10%) had Dissociated vertical deviation (DVD). Four cases 10% were of grade 1, 20 cases (50%) grade 2 and 16 cases (40%) were of grade 3. Of eighty eyes, 66 eyes (82.5%) were fully corrected with no residual IOOA, and 14 eyes (17.5%) were under corrected. V-pattern was corrected in 28 cases 70% and only 12cases (30%) had residual V-pattern grade 1. CONCLUSIONS: Graded recession is an effective procedure for correction of V pattern strabismus with various grades of primary inferior oblique overaction. It can be tailored according to the the degree of IO overaction which is significantly related to the grade of V pattern. The 8 mm recession for IO was significantly related to recurrence or inadequate break of the V pattern in our studied cases. The grade of IOOA correlates with the amplitude of V-pattern. The amount of recession was planned according to preoperative IOOA and grade of V-pattern with frequent undercorrections obtained by the standard 8 mm recession. A + 2 overaction merits a 10-mm recession of the inferior oblique. A + 3 or + 4 overaction merits a 14-mm maximal recession.


Assuntos
Transtornos da Motilidade Ocular , Doenças Orbitárias , Estrabismo , Humanos , Pré-Escolar , Criança , Adolescente , Músculos Oculomotores/cirurgia , Resultado do Tratamento , Procedimentos Cirúrgicos Oftalmológicos/métodos , Visão Binocular , Estrabismo/cirurgia , Estudos Retrospectivos
15.
J Phys Chem Lett ; 14(40): 9136-9144, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37795957

RESUMO

The surface quality of lead halide perovskite crystals can extremely influence their optoelectronic properties and device performance. Here, we report a surface engineering crystallization technique in which we in situ grow a polycrystalline methylammonium lead tribromide (MAPbBr3) film on top of bulk mm-sized single crystals. Such MAPbBr3 crystals with a MAPbBr3 passivating film display intense green emission under UV light. X-ray photoelectron spectroscopy demonstrates that these crystals with emissive surfaces are compositionally different from typical MAPbBr3 crystals that show no emission under UV light. Time-resolved photoluminescence and electrical measurements indicate that the MAPbBr3 film/MAPbBr3 crystals possess less surface defects compared to the bare MAPbBr3 crystals. Therefore, X-ray detectors fabricated using the surface-engineered MAPbBr3 crystals provide an almost 5 times improved sensitivity to X-rays and a more stable baseline drift with respect to the typical MAPbBr3 crystals.

16.
Sci Rep ; 13(1): 12623, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537206

RESUMO

CO2 laser ablation is a rapid and precise technique for machining microfluidic devices. And also, low-cost epoxy resin (ER) proved the great feasibility of fabricating these devices using the CO2 laser ablation technique in our previous studies. However, such a technique has shown negative impacts on such ER-based microfluidics as rough surface microchannels, and thermal defects. Therefore, incorporating different proportions of boric acid (BA) into epoxy resin formulation was proposed to obviate the genesis of these drawbacks in ER-based microfluidics. The structural and optical properties of plain ER- and B-doped ER-based chips were characterized by Fourier transform infrared (FT-IR) and UV/Vis spectral analyses. Furthermore, their thermal properties were studied by thermo-gravimetric (TGA) and differential scanning calorimetric (DSC) analysis. A CO2 laser ablation machine was used in vector mode to draw the designed micro-channel pattern onto plain ER- and B-doped ER-based chips. The quality of microchannels engraved onto these chips was assessed using 3D laser microscopy. This microscopic examination showed a noticeable reduction in the surface roughness and negligible bulge heights in the laser-ablated micro-channels. On the other hand, overall and specific migration using gravimetric methods and gas chromatography-mass spectrometry (GC-MS), respectively, and PCR compatibility test were performed to explore the convenience of these micro-plates for the biological reactions. These findings validated the applicability of B-doped ER-based microfluidics in bio-analytical applications as a result of the effective role of boric acid in enhancing the thermal properties of these chips leading to get micro-channels with higher quality with no effect on the biological reactions.

17.
RSC Adv ; 13(32): 22538-22548, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37497095

RESUMO

In this study, a newly-designed copper(ii) complex of metformin and l-proline which was immobilized on Fe3O4 MNPs was developed. The structure of the catalyst platform was fully characterized using spectroscopic analyses. Moreover, the catalytic activity of [Fe3O4@Cu(ii)(Met)(Pro-H)2] was investigated in a one-pot synthesis of a variety of functionalized ethers in reasonable to excellent yields through Ullman reaction in an aqueous environment using various aryl halides, phenol, and Cs2CO3 and without using any external Cu-reducing agents. Notably, gentle catalytic conditions, quick reaction times, applicability, low cost, and preventing dangerous chemicals and solvents during synthesis and catalytic application are some of the superior properties of the [Fe3O4@Cu(ii)(Met)(Pro-H)2] complex. Furthermore, the catalyst can be reused for several runs (at least eight times) without remarkable loss in efficiency.

18.
ACS Appl Mater Interfaces ; 15(23): 28166-28174, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37259773

RESUMO

One major concern toward the performance and stability of halide perovskite-based optoelectronic devices is the formation of metallic lead that promotes nonradiative recombination of charge carriers. The origin of metallic lead formation is being disputed whether it occurs during the perovskite synthesis or only after light, electron, or X-ray beam irradiation or thermal annealing. Here, we show that the quantity of metallic lead detected in perovskite crystals depends on the concentration and composition of the precursor solution. Through a controlled crystallization process, we grew black-colored mixed dimethylammonium (DMA)/methylammonium (MA) lead tribromide crystals. The black color is suggested to be due to the presence of small lead clusters. Despite the unexpected black coloring, the crystals show higher crystallinity and less defect density with respect to the standard yellow-colored DMA/MAPbBr3 crystals, as indicated by X-ray rocking curve and dark current measurements, respectively. While the formation of metallic lead could still be induced by external factors, the precursor solution composition and concentration can facilitate the formation of metallic lead during the crystallization process. Our results indicate that additional research is required to fully understand the perovskite precursor solution chemistry.

20.
World J Microbiol Biotechnol ; 39(8): 212, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37256458

RESUMO

Biofilm-related infections substantially contribute to bacterial illnesses, with estimates indicating that at least 80% of such diseases are linked to biofilms. Biofilms exhibit unique metabolic patterns that set them apart from their planktonic counterparts, resulting in significant metabolic reprogramming during biofilm formation. Differential glycolytic enzymes suggest that central metabolic processes are markedly different in biofilms and planktonic cells. The glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is highly expressed in Staphylococcus aureus biofilm progenitors, indicating that changes in glycolysis activity play a role in biofilm development. Notably, an important consideration is a correlation between elevated cyclic di-guanylate monophosphate (c-di-GMP) activity and biofilm formation in various bacteria. C-di-GMP plays a critical role in maintaining the persistence of Pseudomonas aeruginosa biofilms by regulating alginate production, a significant biofilm matrix component. Furthermore, it has been demonstrated that S. aureus biofilm development is initiated by several tricarboxylic acid (TCA) intermediates in a FnbA-dependent manner. Finally, Glucose 6-phosphatase (G6P) boosts the phosphorylation of histidine-containing protein (HPr) by increasing the activity of HPr kinase, enhancing its interaction with CcpA, and resulting in biofilm development through polysaccharide intercellular adhesion (PIA) accumulation and icaADBC transcription. Therefore, studying the metabolic changes associated with biofilm development is crucial for understanding the complex mechanisms involved in biofilm formation and identifying potential targets for intervention. Accordingly, this review aims to provide a comprehensive overview of recent advances in metabolomic profiling of biofilms, including emerging trends, prevailing challenges, and the identification of potential targets for anti-biofilm strategies.


Assuntos
Biofilmes , Staphylococcus aureus , Staphylococcus aureus/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Metabolômica , Fosforilação , Regulação Bacteriana da Expressão Gênica , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo
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