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1.
RSC Adv ; 14(19): 13374-13383, 2024 Apr 22.
Article En | MEDLINE | ID: mdl-38660528

Carbon-based perovskite solar cells (PSCs) have emerged as a hopeful alternative in the realm of photovoltaics. They are considered promising due to their affordability, remarkable durability in humid environments, and impressive electrical conductivity. One approach to address the cost issue is to use affordable counter electrodes in PSCs that do not require organic hole transport materials (HTMs). This study utilized an innovative and economical method to create NiOx/PANI nanocomposites. Later, these nanoparticles were integrated into a carbon paste to act as an HTM. This incorporation is intended to optimize charge extraction, improve interfacial contact, align energy levels, reduce energy loss, minimize charge recombination, and protect the perovskite (FAPbI3) surface from degradation. The optoelectronic properties of these devices were investigated, and all cells showed improved efficiency compared to control cells. The NiOx/PANI doped carbon (NiOx/PANI+CE) exhibited excellent performance due to strong hole conductivity, well-aligned energy levels, and the formation of stepwise band alignment at the perovskite interface.

2.
Int J Biol Macromol ; 263(Pt 2): 130211, 2024 Apr.
Article En | MEDLINE | ID: mdl-38423902

Nanocatalysts are vital in several domains, such as chemical processes, energy generation, energy preservation, and environmental pollution mitigation. An experimental study was conducted at room temperature to evaluate the catalytic activity of the new gelatin-chitosan hydrogel/CuO/Fe3O4 nanocomposite in the asymmetric Hantzsch reaction. All components of the nanocomposite exhibit a synergistic effect as a Lewis acid, promote the reaction. Dimedone, ammonium acetate, ethyl acetoacetate, and other substituted aldehydes were used to synthesize diverse polyhydroquinoline derivatives. The nanocomposite exhibited exceptional efficacy (over 90 %) and durability (retaining 80 % of its original capacity after 5 cycles) as a catalyst in the one-pot asymmetric synthesis of polyhydroquinoline derivatives. Also, turnover numbers (TON) and turnover frequency (TOF) have been checked for catalyst (TON and TOF = 50,261 and 100,524 h-1) and products. The experiment demonstrated several benefits, such as exceptional product efficacy, rapid reaction time, functioning at ambient temperature without specific requirements, and effortless separation by the use of an external magnet after the reaction is finished. The results suggest the development of a magnetic nanocatalyst with exceptional performance. The composition of the Ge-CS hydrogel/CuO/Fe3O4 nanocomposite was thoroughly analyzed using several methods including FT-IR, XRD, FE-SEM, EDX, VSM, BET, and TGA. These analyses yielded useful information into the composition and characteristics of the nanocomposite, hence further enhancing the knowledge of its possible uses.


Chitosan , Nanocomposites , Nanoparticles , Chitosan/chemistry , Copper/chemistry , Gelatin , Spectroscopy, Fourier Transform Infrared , Hydrogels , Magnetic Phenomena , Oxides , Nanocomposites/chemistry
3.
Int J Biol Macromol ; 260(Pt 1): 129367, 2024 Mar.
Article En | MEDLINE | ID: mdl-38218269

The study focused on creating a novel and environmentally friendly nanocatalyst using cellulose (Cell), ß-Cyclodextrin (BCD), graphene oxide (GO), Cu2O, and Fe3O4.The nanocatalyst was prepared by embedding GO and Cu2O into Cell-BCD hydrogel, followed by the in-situ preparation of Fe3O4 magnetic nanoparticles to magnetize the nanocomposite. The effectiveness of this nanocatalyst was evaluated in the one-pot, three-component symmetric Hantzsch reaction for synthesizing 1,4-dihydropyridine derivatives with high yield under mild conditions. This novel nanocatalyst has the potential for broad application in various organic transformations due to its effective catalytic activity, eco-friendly nature, and ease of recovery.


Cyclodextrins , Graphite , Nanocomposites , Nanoparticles , Hydrogels , Magnetic Phenomena , Cellulose
4.
Pathol Res Pract ; 251: 154848, 2023 Nov.
Article En | MEDLINE | ID: mdl-37862919

Despite the development of numerous therapies, cancer remains an incurable disease due to various factors, including drug resistance produced by cancer cells. MicroRNAs (miRNAs) regulate different target genes involved in biological and pathological processes, including cancer, through post-transcriptional mechanisms. The development of drug resistance in cancer treatment is a significant barrier because it decreases drug uptake, cellular transport, and changes in proteins involved in cell proliferation, survival, and apoptotic pathways. Numerous studies have found a connection between miRNAs and the development of drug resistance in cancer cells. This paper provides a broad overview of how miRNAs regulate signaling pathways and influence treatment resistance in different cancers.


MicroRNAs , Neoplasms , Humans , MicroRNAs/metabolism , Comprehension , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic/genetics , Neoplasms/drug therapy , Neoplasms/genetics , Signal Transduction
5.
Pathol Res Pract ; 248: 154675, 2023 Aug.
Article En | MEDLINE | ID: mdl-37531833

A significant number of women are identified with breast cancer (BC) every year, making it among the most prevalent malignancies and one of the leading causes of mortality globally. Despite significant progress in understanding BC pathogenesis and treatment options, there is still a need to identify new therapeutic targets and develop more effective treatments. LncRNAs have been discovered as biomarkers and a promising target for various cancers, including BC. PVT1 is a particular one of these lncRNAs, and research has indicated that it has a significant impact on the appearance and progression of BC.PVT1 is an attractive therapeutic target for BC due to its role in promoting cancer cell growth, metastasis and invasion. In addition to its potential as a treatment strategy, PVT1 may also have diagnostic value in BC. In this article, we will discuss targeting PVT1 as a treatment strategy for BC.


Breast Neoplasms , RNA, Long Noncoding , Humans , Female , Breast Neoplasms/genetics , Breast Neoplasms/pathology , RNA, Long Noncoding/genetics , Gene Expression Regulation, Neoplastic/genetics
6.
Pathol Res Pract ; 249: 154664, 2023 Sep.
Article En | MEDLINE | ID: mdl-37573621

Oxidative stress is a physiological condition that occurs when there is an imbalance between the production of reactive oxygen species (ROS) and the cell's antioxidant defense system. ROS are highly reactive molecules that can cause damage to cellular structures such as DNA, proteins, and lipids. the regulation of ROS levels and the antioxidant defense system is crucial for cancer prevention and treatment. Strategies to enhance antioxidant defenses or induce oxidative stress selectively in cancer cells are being developed as potential therapeutic approaches. targeting oxidative stress in cancer treatment is an active area of research with several potential therapeutic approaches being investigated. Developing selective and effective therapies that target oxidative stress in cancer cells while sparing normal cells will be crucial for improving cancer treatment outcomes.


Antioxidants , Neoplasms , Humans , Reactive Oxygen Species/metabolism , Antioxidants/metabolism , Oxidative Stress/physiology , Proteins/metabolism , Neoplasms/metabolism
8.
Article En | MEDLINE | ID: mdl-34379967

BACKGROUND: Topical corticosteroid (TCS) abuse is rampant and results in steroid addiction labeled as topical steroid-dependent or damaged face (TSDF). Indian market is replete with triple combination creams containing TCS sold as over-the-counter products at low cost, luring people to use them without prescription. The resultant damage if detected late is irreversible and difficult to treat. Dermoscopy can help in the early identification of features of TSDF at a preclinical stage resulting in better prognosis. However, the literature on the same is limited. AIMS: This study is undertaken to characterize dermoscopic features of TSDF and to correlate them with potency and duration of application of the TCS. METHODS: One hundred and thirty-two patients aged 18 years or above, with clinical symptoms and signs suggestive of TSDF and with history of application of TCS on the face for a period of more than one month, were enrolled in the study. Their demographic details, clinical features, and dermoscopy findings were recorded using a predesigned structured format. Comparison of dermoscopic findings with clinical examination, gender, potency of TCS, and duration of TCS use was done using Chi-square test, Fisher's exact test, and one-tailed Z-test. RESULTS: Mean age of the patients was 31.7 ± 8.1 years. Male to female ratio was 2:9. Sixty-nine (52.3%) patients abused TCS for more than one year. Clinical findings noted in the patients were erythema (81.1%), hyperpigmentation (80.3%), and hypertrichosis (68.2%). The most common dermoscopy findings seen were brown globules (96.2%), red diffuse areas (92.4%), vessels (87.1%), white structureless areas (86.4%), and hypertrichosis (80.3%). Red diffuse areas, vessels, brown globules, white structureless areas, and white hair were observed in a statistically higher proportion of cases dermoscopically. Y-shaped vessels and brown globules were seen in significantly higher number of patients, using TCS for more than three months and in those continuing it beyond six months, polygonal vessels were predominant. LIMITATIONS: Lack of histopathological correlation is the limitation of our study. Furthermore, brown globules seen in 96.2% patients of TSDF on dermoscopy may have been over-estimated and not always signify TSDF; instead, it could represent melasma for which patient applied TCS. CONCLUSION: Dermoscopy in TSDF can help dermatologists in a multitude of ways from confirming the diagnosis to differentiating from other causes of red face and predicting the approximate duration of TCS abuse.


Dermoscopy , Drug Eruptions/pathology , Glucocorticoids/adverse effects , Administration, Topical , Adult , Cross-Sectional Studies , Erythema/chemically induced , Erythema/pathology , Female , Humans , Male , Telangiectasis/chemically induced , Telangiectasis/pathology
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