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1.
Heliyon ; 10(14): e34505, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39149058

RESUMO

Absolute value equations (AVEs) play a crucial role in solving various complexities across scientific computing, engineering, management science, and operations research. This article presents two fixed-point iteration schemes designed for such AVEs. Furthermore, we show some convergence conditions under specific circumstances. Lastly, the theoretical findings are validated using numerical examples, which emphasize the distinct advantages offered by the newly developed schemes. These results are highly promising and may stimulate future research in this domain.

2.
Heliyon ; 10(15): e34930, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39144939

RESUMO

The natural convection in cavities is frequently used in fluid mechanics and heat transfer engineering, such as heat exchangers, electronics, solar collectors, and growing crystals. However, the physics of natural convection flow and heat transfer in cavities with split baffles is least understood. The fundamental aim of this research is to investigate the impact of heated split baffles positioned at various locations on steady-state free convection within a sinusoidal corrugated star cavity. In this model configuration, the outer wavy enclosure is maintained at a constant temperature of T c , while the inner split baffles are heated at a constant temperature of T h . The finite element method is employed to discretize and solve the governing equations describing the fluid flow and heat transfer within the enclosure. This numerical approach aimed to analyze the effects of baffle inclination angles, baffle spacing, Rayleigh number on the fluid dynamics and convective thermal transport characteristics. The variation in velocity and temperature profile is illustrated through the streamlines and isotherm contours. Moreover, the numerical result is displayed in term N u a v g of the heat transfer, which are analyzed for inside space of baffles and angles of the baffle ( θ = 0 0 , 45 0 , 90 0 ) . The key finding demonstrates that increasing the Rayleigh numbers and the different positions (up, central, down) of inner vertical split baffles enhances the magnitude of the velocity by 88.1 % , 85.9 and 89.6 % respectively. Furthermore, for the inner rectangular split baffle angles of 0 ° , 45 ° , and 90 ° , and within the Rayleigh number range of 10 4 to 10 6 , the N u a v g exhibits significant variations, with maximum increases of 71.9 % , 46.7 % and a subsequent decrease of 45.9 % .

3.
Top Curr Chem (Cham) ; 382(3): 27, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033235

RESUMO

Supramolecular polymers are polymeric materials of monomeric fragments, held jointly by reversible and directional non-covalent interactions such as multiple hydrogen-bonding, charge transfer effects, host-guest interactions, metal coordination, and aromatic stacking. This review article on the Hamilton-based supramolecular polymers aims to shed light on the molecular recognition achievements by the Hamilton-based polymeric systems, evaluate Hamilton receptor's future prospects, and capitalize its potential applications in supramolecular chemistry. To the best of our knowledge, this is the first elaborative and sole manuscript in which polymeric Hamilton receptors are being exposed in detail. The first portion of this manuscript is related to the importance and urgency of polymers along with the historic background of Hamilton receptors. The middle section discloses the potential applications of Hamilton-type receptors in various fields, e.g., dendrimers, mechanically polymeric rotaxanes, and self-assemblies. The final section of the manuscript discloses the future aspects and the importance of novel polymer-based Hamilton-type receptors in the modern era. We believe that this first review in this emerging yet immature field will be useful to inspire scientists around the world to find the unseen future prospects, thereby boosting the field related to this valued artificial receptor in the province of supramolecular chemistry and also in other domains of scientific fields and technology, as well.


Assuntos
Polímeros , Polímeros/química , Substâncias Macromoleculares/química , Rotaxanos/química , Dendrímeros/química , Estrutura Molecular , Receptores Artificiais/química , Receptores Artificiais/metabolismo , Ligação de Hidrogênio
4.
J Mater Chem B ; 12(24): 5950-5956, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38804847

RESUMO

Therapeutic applications have sparked increased interest in the use of synthetic anion receptors for ion transport across lipid membranes. In this context, the construction of synthetic transmembrane transporters for the physiologically important chloride ion is currently of enormous interest. As a result, considerable effort is being devoted to the design and synthesis of artificial transmembrane chloride ion transporters. However, only inadequate progress has been made in developing macrocyclic chloride ion transporters using the fundamental principles of supramolecular chemistry, and hence this field entails fostering investigations. In this investigation, the synthesis of two new double walled trifluorophenyl/phthalimide extended calix[4]pyrrole (C4P) receptors (3 and 7) has been successfully reported. 1H-NMR titration and HRMS studies confirmed the 1 : 1 binding stoichiometry of the chloride ion with these receptors in the solution phase (only receptor 3b was studied by 1H-NMR). Regarding ion transport of 3b and 7, when studied in the HPTS-based vesicular system, 3b showed better activity with an EC50 value of 0.39 µM. The detailed ion transport studies on 3b have revealed that ion transport occurs through the Cl-/NO3- antiport mode.


Assuntos
Calixarenos , Porfirinas , Membrana Celular/química , Membrana Celular/metabolismo , Modelos Moleculares , Conformação Molecular , Porfirinas/química , Calixarenos/química , Ftalimidas/química , Flúor/química , Cloretos/química , Íons/química
5.
Microbiol Spectr ; 12(6): e0361723, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38624222

RESUMO

We conducted a comprehensive analysis of the total microbiome and transcriptionally active microbiome communities in the roots and root nodules of Prosopis cineraria, an important leguminous tree in arid regions of many Asian countries. Mature P. cineraria trees growing in the desert did not exhibit any detected root nodules. However, we observed root nodules on the roots of P. cineraria growing on a desert farm and on young plants growing in a growth chamber, when inoculated with rhizosphere soil, including with rhizosphere soil from near desert tree roots that had no nodules. Compared to nearby soil, non-nodulated roots were enriched with Actinobacteria (e.g., Actinophytocola sp.), whereas root nodules sampled from the desert farm and growth chamber had abundant Alphaproteobacteria (e.g., Ensifer sp.). These nodules yielded many microbes in addition to such nitrogen-fixing bacteria as Ensifer and Sinorhizobium species. Significant differences exist in the composition and abundance of microbial isolates between the nodule surface and the nodule endosphere. Shotgun metagenome analysis of nodule endospheres revealed that the root nodules comprised over 90% bacterial DNA, whereas metatranscriptome analysis showed that the plant produces vastly more transcripts than the microbes in these nodules. Control inoculations demonstrated that four out of six Rhizobium, Agrobacterium, or Ensifer isolates purified from P. cineraria nodules produced nodules in the roots of P. cineraria seedlings under greenhouse conditions. The best nodulation was achieved when seedlings were inoculated with a mixture of those bacterial strains. Though root nodulation could be achieved under water stress conditions, nodule number and nodule biomass increased with copious water availability. .IMPORTANCEMicrobial communities were investigated in roots and root nodules of Prosopis cineraria, a leguminous tree species in arid Asian regions that is responsible for exceptionally important contributions to soil fertility in these dramatically dry locations. Soil removed from regions near nodule-free roots on these mature plants contained an abundance of bacteria with the genetic ability to generate nodules and fix nitrogen but did not normally nodulate in their native rhizosphere environment, suggesting a very different co-evolved relationship than that observed for herbaceous legumes. The relative over-expression of the low-gene-density plant DNA compared to the bacterial DNA in the nodules was also unexpected, indicating a very powerful induction of host genetic contributions within the nodule. Finally, the water dependence of nodulation in inoculated seedlings suggested a possible link between early seedling growth (before a deep root system can be developed) and the early development of nitrogen-fixing capability.


Assuntos
Clima Desértico , Microbiota , Prosopis , Rizosfera , Nódulos Radiculares de Plantas , Microbiologia do Solo , Nódulos Radiculares de Plantas/microbiologia , Prosopis/microbiologia , Prosopis/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Simbiose , Árvores/microbiologia , Fixação de Nitrogênio , Filogenia
6.
ACS Omega ; 9(8): 9098-9108, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434898

RESUMO

In recent years, truxenes and related polyaromatic hydrocarbons (PAHs) have engrossed ample interest of the scientific community because of their ease of synthesis, functionalizations, and use as building blocks for the synthesis of fullerene fragments, liquid crystals, larger polyarenes, and C3-tripod materials. In the present work, we have disclosed an ingenious method for the construction of various indolo-truxene hybrid molecules in good yields (52-90%), by means of the acid-catalyzed cotrimerization, Friedel-Crafts acylation, and Fischer indole synthesis, and fully characterized them through the standard spectroscopic techniques. The photophysical properties of the thus-prepared compounds have also been investigated using steady-state absorption and fluorescence and time-resolved fluorescence spectroscopy techniques. Moreover, the density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations have been studied to correlate them with the measured photophysical properties of the synthesized indolo-truxene derivatives.

7.
RSC Adv ; 14(11): 7786-7796, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38444971

RESUMO

In this paper, we have design, synthesized and fully characterized a new meso-fluorescein substituted one-walled calix[4]pyrrole (C4P7), obtained from simple and easily available starting materials such as fluorescein, 4-hydroxyacetophenone and pyrrole. The anion sensing studies reveal that the C4P7 system displays selective and sensitive naked-eye sensing towards fluoride, phosphate, and acetate anions with the limit of detection of 4.27 mg L-1, 6.4 mg L-1, and 5.94 mg L-1, respectively. Moreover, the C4P7 receptor displays good results of binding (host-guest, 1 : 1) towards a variety of anions. The 1 : 1 binding stoichiometry was further confirmed by means of Job's plots. TD-DFT calculations showed that the HOMO-LUMO gap decreases in all the complexes (C4P7@anions) in comparison to the free C4P7 system. The authors are of the opinion that this work may provide a good platform to explore calix[4]pyrrole chemistry in the arena of recognition/sensing of biologically significant analytes in future studies.

8.
Int Urol Nephrol ; 56(8): 2607-2613, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38549000

RESUMO

INTRODUCTION: Ureteropelvic junction obstruction (UPJO) is a commonly encountered abnormality and it can lead to serious consequences such as renal dysplasia eventually resulting in loss of kidney. Hence, early diagnosis and timely management remains the cornerstone of the treatment. The most anticipated technique amongst modern day urologist is the robot-assisted laparoscopic pyeloplasty (RALP). The study aims to determine early post-operative outcomes of robot-assisted laparoscopic transperitoneal pyeloplasty procedure in patients presenting with unilateral ureteropelvic junction obstruction to establish the local perspective. METHODOLOGY: This is a descriptive study involving patients with ureteropelvic junction obstruction in a tertiary care facility in Karachi; Sindh Institute of Urology and Transplant (SIUT). A total of 46 participants were recruited. Robot-assisted laparoscopic transperitoneal dismembered Hynes-Anderson pyeloplasty was performed by a single surgeon with over 3 years of experience in the presence of the researcher. Early postoperative outcome total operative time, length of hospital stay, console time and blood loss were noted by the researcher as per operational definition. Data were analyzed on SPSS Version 22. RESULTS: Mean age in our study was 46.51 years with the standard deviation of ± 10.87. Whereas, mean length of hospital stay, total operative time, total blood loss, console time, pre-hemoglobin, posthemoglobin, height, weight and BMI in our study was 1.19 ± 0.40 days, 64.58 ± 17.59 min, 9.56 ± 6.13 ml, 30.17 ± 4.99 min, 12.66 ± 1.47 ml, 11.79 ± 1.93 ml, 165.62 ± 8.23 cm, 68.34 ± 8.23 kg and 24.85 ± 3.34 kg/m2, respectively. CONCLUSION: Recent advancements in technology have yielded the latest RALP technique which has been proven significantly better than existing approaches and similar results are reported by this study demonstrating improvement in peri-operative and post-operative outcomes ultimately ameliorating the quality of life of patients with UPJO.


Assuntos
Pelve Renal , Procedimentos Cirúrgicos Robóticos , Obstrução Ureteral , Procedimentos Cirúrgicos Urológicos , Humanos , Obstrução Ureteral/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Pelve Renal/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto , Procedimentos Cirúrgicos Urológicos/métodos , Laparoscopia/métodos , Fatores de Tempo , Tempo de Internação , Duração da Cirurgia
9.
Anticancer Agents Med Chem ; 24(5): 379-388, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38305390

RESUMO

BACKGROUND: Platinum complexes are commonly used for cancer chemotherapy; however, they are not only highly-priced but also have various side effects. It is, therefore, important to design affordable anticancer drugs with minimal side effects. METHODS: We synthesized a new gold(I) complex, PF6{(BDPEA)(TPPMS) digold(I)} (abbreviated as PBTDG) and tested its cytotoxicity in MCF-7 breast cancer cells. We also evaluated the effects of PBTDG on mitochondrial membrane potential, generation of reactive oxygen species (ROS) and apoptosis in breast cancer cells. RESULTS: The IC50 values for PBTDG and sorafenib were found to be 1.48 µM and 4.45 µM, respectively. Exposure to PBTDG caused significant and concentration-dependent depletion of ATP and disruption of mitochondrial membrane potential. PBTDG induced 2.6, 3.6, and 5.7-fold apoptosis for 1 µM, 3 µM, and 10 µM concentrations, respectively. The induction of apoptosis by the same concentrations of sorafenib was 1.2, 1.3, and 1.6-fold, respectively. The low concentration of PBTDG (1 µM) induced the generation of ROS by 99.83%, which was significantly higher than the ROS generation caused by the same concentration of sorafenib (73.76%). The ROS induction caused by higher concentrations (5 µM) of PBTDG and sorafenib were 104.95% and 122.11%, respectively. CONCLUSION: The lower concentration of PBTDG produced similar cytotoxicity and apoptotic effects that were caused by a comparatively higher concentration of known anticancer drug (sorafenib). The anticancer effects of PBTDG are attributed to its tendency to disrupt mitochondrial membrane potential, induction of apoptosis and generation of ROS. Further studies are warranted to test the anticancer effects of PBTDG in animal models of cancer.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Animais , Espécies Reativas de Oxigênio , Sorafenibe/farmacologia , Antineoplásicos/farmacologia , Células MCF-7 , Apoptose , Linhagem Celular Tumoral , Potencial da Membrana Mitocondrial
10.
Molecules ; 28(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38138453

RESUMO

Thin films of zinc oxide (ZnO) doped with transition metals have recently gained significant attention due to their potential applications in a wide range of optoelectronic devices. This study focuses on ZnO thin films doped with the transition metals Co, Fe, and Zr, exploring various aspects of their structural, morphological, optical, electrical, and photoluminescence properties. The thin films were produced using RF and DC co-sputtering techniques. The X-ray diffraction (XRD) analysis revealed that all the doped ZnO thin films exhibited a stable wurtzite crystal structure, showcasing a higher structural stability compared to the undoped ZnO, while the atomic force microscopy (AFM) imaging highlighted a distinctive granular arrangement. Energy-dispersive X-ray spectroscopy was employed to confirm the presence of transition metals in the thin films, and Fourier-transform infrared spectroscopy (FTIR) was utilized to investigate the presence of chemical bonding. The optical characterizations indicated that doping induced changes in the optical properties of the thin films. Specifically, the doped ZnO thin film's bandgap experienced a significant reduction, decreasing from 3.34 to 3.30 eV. The photoluminescence (PL) analysis revealed distinguishable emission peaks within the optical spectrum, attributed to electronic transitions occurring between different bands or between a band and an impurity. Furthermore, the introduction of these transition metals resulted in decreased resistivity and increased conductivity, indicating their positive influence on the electrical conductivity of the thin films. This suggests potential applications in solar cells and light-emitting devices.

11.
RSC Adv ; 13(43): 30420-30428, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37849701

RESUMO

Two novel fluorescein as well as benzo-12-crown-4 ether functionalized dipyrromethane receptors (DPM3 and DPM4) have successfully been synthesized. The anion (used as their TBA salts) binding studies of thus prepared DPM3 and DPM4 receptors were evaluated by the UV-visible spectrophotometric titrations. Binding affinities as well as the stoichiometry were determined through the UV-visible titrations data with the involvement of the BindFit (v0.5) package available online at https://supramolecular.org. Moreover, binding events were validated by means of the comparison of the partial 1H-NMR spectrum of the simple host molecule with that of the host-guest complex, and the 1 : 1 stoichiometry were further confirmed by the Job's method of continuous variation. From the results, we observed the binding constant (Ka) values of DPM3/DPM4 with various tested anions in the range of 516.07 M-1 to 63789.81 M-1, depending upon the nature/shape/size of the anions. Moreover, the anion-π interactions were confirmed by the partial 1H-NMR spectral data, and further supported by the literature reported systems. The authors hope that such types of valued receptors will be benefitted in future for the recognizing/binding of a variety of biologically important anions.

12.
Int J Mycobacteriol ; 12(3): 310-315, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37721238

RESUMO

Background: Nontuberculous mycobacteria (NTM) are increasingly identified as causes of protracted pulmonary infections. Antibiotic susceptibility testing requires microdilution methods, which are often unavailable in laboratories in resource-poor settings. We report cumulative antibiograms for the most frequently isolated clinical pulmonary NTM from Pakistan to inform empiric antibiotic management of initial NTM infections. Methods: We analyzed data from 2018 to 2022 for the most frequently isolated and clinically relevant NTM isolated from respiratory specimens, i.e., Mycobacterium avium complex (MAC), Mycobacterium abscessus group (MAG), and Mycobacterium kansasii (MK). Antibiograms were developed using the Clinical Laboratory Standards Institute's M39ED5 standard. Percentage susceptibilities and 95% confidence intervals (CI) were calculated. Results: Over 4 years, 529 NTM, comprising 209 MAC, 249 MAG, and 71 MK were analyzed. For MAC and MAG, where clarithromycin (CLR)-based regimens are recommended, CLR was active for 94.8% (95% CI 91.3-96.9), and 77.5% (95% CI 71.4-82.7) isolates, respectively. Combination regimens comprising 3 active drugs CLR + linezolid (LZD) + moxifloxacin for MAC and CLR + LZD + Amikacin for MAG had 98.4% (95% CI 95.9-99.4) and 68.9% (95% CI 62.3-74.8) coverage for pulmonary disease, respectively. For MK, 91.5% (95% CI 82.8-96.1) isolates were susceptible to rifampin (RIF), with a combination of RIF + CLR covering 88.7% (95% CI 79.3-94.2) of MK pulmonary infections, respectively. Conclusions: These data can inform empiric treatment guidance for the most common NTM pulmonary infections, i.e., for MAC, MAG, and MK disease in Pakistan.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Infecção por Mycobacterium avium-intracellulare , Mycobacterium kansasii , Humanos , Complexo Mycobacterium avium , Paquistão , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina , Linezolida , Rifampina/uso terapêutico , Testes de Sensibilidade Microbiana
13.
PeerJ Comput Sci ; 9: e1521, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705660

RESUMO

Cybersecurity guarantees the exchange of information through a public channel in a secure way. That is the data must be protected from unauthorized parties and transmitted to the intended parties with confidentiality and integrity. In this work, we mount an attack on a cryptosystem based on multivariate polynomial trapdoor function over the field of rational numbers Q. The developers claim that the security of their proposed scheme depends on the fact that a polynomial system consisting of 2n (where n is a natural number) equations and 3n unknowns constructed by using quasigroup string transformations, has infinitely many solutions and finding exact solution is not possible. We explain that the proposed trapdoor function is vulnerable to a Gröbner basis attack. Selected polynomials in the corresponding Gröbner basis can be used to recover the plaintext against a given ciphertext without the knowledge of the secret key.

14.
Heliyon ; 9(7): e18183, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37501952

RESUMO

A Multi-Criteria Recommender System (MCRS) represents users' preferences on several factors of products and utilizes these preferences while making product recommendations. In recent studies, MCRS has demonstrated the potential of applying Multi-Criteria Decision Making methods to make effective recommendations in several application domains. However, eliciting actual user preferences is still a major challenge in MCRS since we have many criteria for each product. Therefore, this paper proposes a three-phase adaptive genetic algorithm-based approach to discover user preferences in MCRS. Initially, we build a model by assigning weights to multi-criteria features and then learn the preferences on each criteria during similarity computation among users through a genetic algorithm. This allows us to know the actual preference of the user on each criteria and find other like-minded users for decision making. Finally, products are recommended after making predictions. The comparative results demonstrate that the proposed genetic algorithm based approach outperforms both multi-criteria and single criteria based recommender systems on the Yahoo! Movies dataset based on various evaluation measures.

15.
J Imaging ; 9(2)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36826961

RESUMO

A rapidly spreading epidemic, COVID-19 had a serious effect on millions and took many lives. Therefore, for individuals with COVID-19, early discovery is essential for halting the infection's progress. To quickly and accurately diagnose COVID-19, imaging modalities, including computed tomography (CT) scans and chest X-ray radiographs, are frequently employed. The potential of artificial intelligence (AI) approaches further explored the creation of automated and precise COVID-19 detection systems. Scientists widely use deep learning techniques to identify coronavirus infection in lung imaging. In our paper, we developed a novel light CNN model architecture with watershed-based region-growing segmentation on Chest X-rays. Both CT scans and X-ray radiographs were employed along with 5-fold cross-validation. Compared to earlier state-of-the-art models, our model is lighter and outperformed the previous methods by achieving a mean accuracy of 98.8% on X-ray images and 98.6% on CT scans, predicting the rate of 0.99% and 0.97% for PPV (Positive predicted Value) and NPV (Negative predicted Value) rate of 0.98% and 0.99%, respectively.

16.
Top Curr Chem (Cham) ; 381(1): 7, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36607442

RESUMO

The incorporation of aryl substituents at the meso-positions of calix[4]pyrrole (C4P) scaffolds produces aryl-extended (AE) and super-aryl-extended (SAE) calix[4]pyrroles. The cone conformation of the all-α isomers of "multi-wall" AE-C4Ps and SAE-C4Ps displays deep aromatic clefts or cavities. In particular, "four-wall" receptors feature an aromatic polar cavity closed at one end with four convergent pyrrole rings and fully open at the opposite end. This makes AE- and SAE-C4P scaffolds effective receptors for the molecular recognition of negatively charged ions and neutral guest molecules with donor-acceptor and hydrogen bonding motifs. In addition, adequately functionalized all-α isomers of multi wall AE- and SAE-C4P scaffolds self-assemble into uni-molecular and supra-molecular aggregates displaying capsular and cage-like structures. The self-assembly process requires the presence of template ions or molecules that lock the C4P cone conformation and complementing the inner polar functions and volumes of their cavities. We envisioned performing an in-depth revision of AE- and SAE-C4P scaffolds owing to their importance in different domains such as supramolecular chemistry, biology, material sciences and pharmaceutical chemistry. Herewith, besides the synthetic details on the elaboration of their structures, we also draw attention to their diverse applications. The organization of this review is mainly based on the number of "walls" present in the AE-C4P derivatives and their structural modifications. The sections are further divided based on the C4P functions and applications. The authors are convinced that this review will be of interest to researchers working in the general area of supramolecular chemistry as well as those involved in the study of the binding properties and applications of C4P derivatives.


Assuntos
Porfirinas , Pirróis , Pirróis/química , Porfirinas/química , Modelos Moleculares , Íons/química , Conformação Molecular
17.
Polymers (Basel) ; 15(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36679244

RESUMO

The appropriate combination of semiconducting polymer-inorganic nanocomposites can enhance the existing performance of polymers-only-based photovoltaic devices. Hence, polyaniline (PANI)/zinc oxide (ZnO) nanocomposites were prepared by combining ZnO nanoparticles with PANI in four distinct ratios to optimize their photovoltaic performance. Using a simple coating method, PANI, ZnO, and its nanocomposite, with varying weight percent (wt%) concentrations of ZnO nanoparticles, i.e., (1 wt%, 2 wt%, 3 wt%, and 4 wt%), were fabricated and utilized as an active layer to evaluate the potential for the high-power conversion efficiency of various concentrations, respectively. PANI/ZnO nanocomposites are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-vis) absorption, energy dispersive X-ray (EDX), and I-V measurement techniques. The XRD analysis showed a distinct, narrow peak, which corresponds to the wurtzite ZnO (101) plane. The SEM analysis verified the production of the PANI/ZnO composite by demonstrating that the crystalline ZnO was integrated into the PANI matrix. The elemental composition was determined by energy dispersive X-ray analysis (EDX), which confirmed the existence of PANI and ZnO without any impurities, respectively. Using Fourier transform infrared (FTIR) spectroscopy, various chemical bonds and stretching vibrations were analyzed and assigned to different peaks. The bandgap narrowing with an increasing PANI/ZnO composition led to exceptional optical improvement. The I-V characterization was utilized to investigate the impact of the nanocomposite on the electrical properties of the PANI/ZnO, and various concentrations of ZnO (1 wt%, 2 wt%, 3 wt%, and 4 wt%) in the PANI matrix were analyzed under both light and dark conditions at an STC of 1.5 AM globally. A high PCE of 4.48% was achieved for the PANI/ZnO (3 wt%), which revealed that the conductivity of the PANI/ZnO nanocomposite thin films improved with the increasing nanocomposite concentration.

18.
Life Sci ; 316: 121409, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36681183

RESUMO

Chimeric antigen receptor (CAR) T therapy has shown remarkable success in discovering novel CAR-T cell products for treating malignancies. Despite of successful results from clinical trials, CAR-T cell therapy is ineffective for long-term disease progression. Numerous challenges of CAR-T cell immunotherapy such as cell dysfunction, cytokine-related toxicities, TGF-ß resistance, GvHD risks, antigen escape, restricted trafficking, and tumor cell infiltration still exist that hamper the safety and efficacy of CAR-T cells for malignancies. The accumulated data revealed that these challenges could be overcome with the advanced CRISPR genome editing technology, which is the most promising tool to knockout TRAC and HLA genes, inhibiting the effects of dominant negative receptors (PD-1, TGF-ß, and B2M), lowering the risks of cytokine release syndrome (CRS), and regulating CAR-T cell function in the tumor microenvironment (TME). CRISPR technology employs DSB-free genome editing methods that robustly allow efficient and controllable genetic modification. The present review explored the innovative aspects of CRISPR/Cas9 technology for developing next-generation/universal allogeneic CAR-T cells. The present manuscript addressed the ongoing status of clinical trials of CRISPR/Cas9-engineered CAR-T cells against cancer and pointed out the off-target effects associated with CRISPR/Cas9 genome editing. It is concluded that CAR-T cells modified by CRISPR/Cas9 significantly improved antitumor efficacy in a cost-effective manner that provides opportunities for novel cancer immunotherapies.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Sistemas CRISPR-Cas/genética , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Imunoterapia , Neoplasias/genética , Neoplasias/terapia , Linfócitos T , Microambiente Tumoral
19.
Plant J ; 113(6): 1223-1236, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36633062

RESUMO

Plant cyclic nucleotide gated channels (CNGCs) facilitate cytosolic Ca2+ influx as an early step in numerous signaling cascades. CNGC-mediated Ca2+ elevations are essential for plant immune defense and high temperature thermosensing. In the present study, we evaluated phenotypes of CNGC2, CNGC4, CNGC6, and CNGC12 null mutants in these two pathways. It is shown CNGC2, CNGC4, and CNGC6 physically interact in vivo, whereas CNGC12 does not. CNGC involvement in immune signaling was evaluated by monitoring mutant response to elicitor peptide Pep3. Pep3 response cascades involving CNGCs included mitogen-activated kinase activation mediated by Ca2+ -dependent protein kinase phosphorylation. Pep3-induced reactive oxygen species generation was impaired in cngc2, cngc4, and cngc6, but not in cngc12, suggesting that CNGC2, CNGC4, and CNGC6 (which physically interact) may be components of a multimeric CNGC channel complex for immune signaling. However, unlike cngc2 and cngc4, cngc6 is not sensitive to high Ca2+ and displays no pleiotropic dwarfism. All four cngc mutants showed thermotolerance compared to wild-type, although CNGC12 does not interact with the other three CNGCs. These results imply that physically interacting CNGCs may, in some cases, function in a signaling cascade as components of a heteromeric channel complex, although this may not be the case in other signaling pathways.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transdução de Sinais/genética , Fenótipo , Cálcio/metabolismo
20.
Chem Asian J ; 18(2): e202201080, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36412231

RESUMO

Over the past two decades, non-covalent chemistry has introduced various promising artificial receptors and revolutionized the host-guest chemistry. These versatile receptors have particularly been entertained in sensing and recognizing of diverse neutral molecules and/or ionic entities (e. g. anions, cations and ion-pair) of particular interest. Notably, supramolecular chemistry had given birth to a plethora of important molecules, explored in the chemical, biological, environmental, and pharmacological world to resolve the critical issues related to the human health while keeping environmental concerns in mind. Amongst the various types of supramolecular monotopic receptors (anions, cations, and neutral molecules), heteroditopic receptors (ion-pair receptors) consisting of distinct binding sites in one system for both cation and anion, have gained much interest from the scientific community in recent past because of their unique binding abilities. Interestingly, these promising artificial receptors have shown potential applications in sensing, recognition, transport and extraction processes besides their uses in salt/waste purification. Bearing the importance of these systems in mind, we intended to report the recent developments in ion-pair chemistry. Herein, we divided the whole document into three main sections; first one describes the introduction and history of the ion-pairs receptors. The second portion highlights the synthesis and applications of ion-pair receptors in sensing, recognition, molecular machines, photoswitching behaviour, extraction and transport properties, whereas the last part of this manuscript provides concluding remarks as well as future prospects of ion-pair receptors. We hope that this manuscript will be helpful to stimulating researchers around the globe to find out the hidden opportunities in this and related areas.


Assuntos
Calixarenos , Receptores Artificiais , Humanos , Calixarenos/química , Ânions/química , Sítios de Ligação , Cátions/química
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