Efficiency of Crystal Violet Stain to Study Mitotic Figures in Oral Epithelial Dysplasia

AIM: To evaluate mitotic activity in the different grades of oral epithelial dysplasia using 1% crystal violet stain. MATERIAL AND METHODS: A descriptive study was conducted in the Department of Histopathology of the Post Graduate Medical Institute, Lahore on a total of thirty-three cases of the Oral Epithelial Dysplasia (OED). Fresh, frozen paraffin-embedded archival tissue blocks were collected from Lahore General Hospital, Lahore & Oral & Maxillofacial Surgery Department of Nawaz Sharif Hospital, Yakki Gate, Lahore. The representative sections were taken and, after processing, mounted on glass slides and stained with H&E and crystal violet stains. The stained slides were then examined under an optical microscope. The efficacy of 1% crystal violet stain to identify mitotic figures in the different grades of oral epithelial dysplasia was assessed with the sample t-test. A difference of p < 0.05 was considered to be significant. RESULTS: A comparison of the mitotic figure count in two categories in sections stained with both stains showed a statistically significant difference. An increase in the mean mitotic count was noted in the sections of OED stained with crystal violet in comparison to the sections of OED stained with H&E which was statistically significant (p = 0.00). CONCLUSION: Counting of mitotic cell is the rapid and simplest way of evaluating the proliferative activity of cells. Crystal violet stain can be a rationalised step in the staining of mitotic figures compared to the usual H&E staining and can be employed as a selective stain during routine histopathological procedures

Sestrin2 suppression aggravates oxidative stress and apoptosis in endothelial cells subjected to pharmacologically induced endoplasmic reticulum stress

Endoplasmic reticulum (ER) stress is an inflammatory response that contributes to endothelial dysfunction, a hallmark of cardiovascular diseases, in close interplay with oxidative stress. Recently, Sestrin2 (SESN2) emerged as a novel stress-inducible protein protecting cells from oxidative stress. We investigated here, for the first time, the impact of SESN2 suppression on oxidative stress and cell survival in human endothelial cells subjected to pharmacologically (thapsigargin)-induced ER stress and studied the underlying cellular pathways. We found that SESN2 silencing, though did not specifically induce ER stress, it aggravated the effects of thapsigargin-induced ER stress on oxidative stress and cell survival. This was associated with a dysregulation of Nrf-2, AMPK and mTORC1 signaling pathways. Furthermore, SESN2 silencing aggravated, in an additive manner, apoptosis caused by thapsigargin. Importantly, SESN2 silencing, unlike thapsigargin, caused a dramatic decrease in protein expression and phosphorylation of Akt, a critical pro-survival hub and component of the AMPK/Akt/mTORC1 axis. Our findings suggest that patients with conditions characterized by ER stress activation, such as diabetes, may be at higher risk for cardiovascular complications if their endogenous ability to stimulate and/or maintain expression levels of SESN2 is disturbed or impaired. Therefore, identifying novel or repurposing existing pharmacotherapies to enhance and/or maintain SESN2 expression levels would be beneficial in these conditions

Mechanisms of Amyloid Proteins Aggregation and Their Inhibition by Antibodies, Small Molecule Inhibitors, Nano-particles and Nano-bodies

Protein misfolding and aggregation can be induced by a wide variety of factors, such as dominant disease-associated mutations, changes in the environmental conditions (pH, temperature, ionic strength, protein concentration, exposure to transition metal ions, exposure to toxins, posttranslational modifications including glycation, phosphorylation, and sulfation). Misfolded intermediates interact with similar intermediates and progressively form dimers, oligomers, protofibrils, and fibrils. In amyloidoses, fibrillar aggregates are deposited in the tissues either as intracellular inclusion or extracellular plaques (amyloid). When such proteinaceous deposit occurs in the neuronal cells, it initiates degeneration of neurons and consequently resulting in the manifestation of various neurodegenerative diseases. Several different types of molecules have been designed and tested both in vitro and in vivo to evaluate their anti-amyloidogenic efficacies. For instance, the native structure of a protein associated with amyloidosis could be stabilized by ligands, antibodies could be used to remove plaques, oligomer-specific antibody A11 could be used to remove oligomers, or prefibrillar aggregates could be removed by affibodies. Keeping the above views in mind, in this review we have discussed protein misfolding and aggregation, mechanisms of protein aggregation, factors responsible for aggregations, and strategies for aggregation inhibition

The Role of Amyloids in Alzheimer\u27s and Parkinson\u27s Diseases

With varying clinical symptoms, most neurodegenerative diseases are associated with abnormal loss of neurons. They share the same common pathogenic mechanisms involving misfolding and aggregation, and these visible aggregates of proteins are deposited in the central nervous system. Amyloid formation is thought to arise from partial unfolding of misfolded proteins leading to the exposure of hydrophobic surfaces, which interact with other similar structures and give rise to form dimers, oligomers, protofibrils, and eventually mature fibril aggregates. Accumulating evidence indicates that amyloid oligomers, not amyloid fibrils, are the most toxic species that causes Alzheimer\u27s disease (AD) and Parkinson\u27s disease (PD). AD has recently been recognized as the ‘twenty-first century plague’, with an incident rate of 1% at 60 years of age, which then doubles every fifth year. Currently, 5.3 million people in the US are afflicted with this disease, and the number of cases is expected to rise to 13.5 million by 2050. PD, a disorder of the brain, is the second most common form of dementia, characterized by difficulty in walking and movement. Keeping the above views in mind, in this review we have focused on the roles of amyloid in neurodegenerative diseases including AD and PD, the involvement of amyloid in mitochondrial dysfunction leading to neurodegeneration, are also considered in the review

Geospatial assessment of early summer heatwaves, droughts, and their relationship with vegetation and soil moisture in the arid region of Southern Punjab, Pakistan

This study focuses on the spatiotemporal analysis of early summer heatwaves, droughts, and their relationship with vegetation and soil moisture from 2013 to 2022 in South Punjab, Pakistan. The study uses a unique approach of utilizing a combination of meteorological-based maximum air temperature Tmax derived from Modern-Era Retrospective analysis for Research and Applications V.2 (MERRA-2) and remotely sensed land surface temperature (LST) to calculate heatwave metrics. Station-based precipitation (P) and remote sensing-based temperature condition index (TCI) are utilized to calculate droughts. The normalized difference vegetation index (NDVI) and the normalized difference water index (NDWI) are used to analyze the relationship between extreme events with vegetation and soil moisture. The results reveal a significant rise in the region's heatwave frequency, duration, and intensity. Spatiotemporal analysis of the SPI and TCI shows the occurrence of droughts in more heatwave years. Negative Pearson correlation R = 0.5–0.9 and coefficient of determination R2 of 0.76–0.86 of the NDVI and NDWI with drought and heatwave metrics represents a significant (<0.01) relationship and direct response of vegetation and soil moisture towards extreme events. The study affirms the hydrological vulnerability of arid regions due to extreme events and marks the attention to appropriate mitigation and adaptation strategies in the future. HIGHLIGHTS The unusual early summer heat waves in the region made it vulnerable to negative impacts on vegetation and water.; The long-term linear relationship between the Tmax, LST, heatwave metrics, drought indices with vegetation and water reveals a strong linear interdependence.; The region is vulnerable to negative impacts of climate change in the form of agriculture loss which may cause food insecurity.

Nanoparticle Formulations in the Diagnosis and Therapy of Alzheimer\u27s Disease

Alzheimer\u27s disease (AD) is one of the most common age-related diseases that occurs because of the deposition of amyloid fibrils in a form of extracellular plaques containing β-amyloid peptide (Aβ) and tangles are found as intracellular deposit in the brain made up of twisted strands of aggregated microtubule binding protein. Scores of small molecule inhibitors have been designed for the treatment of AD. However some of these drugs cannot pass through the brain-blood-barrier (BBB). To overcome this problem, various nanoparticles (NPs) or nanomedicines (NMs) have been synthesized. These nanoparticles exploit the existing physiological mechanisms of passing through the BBB, including receptor- and adsorptive-mediated transcytosis that facilitate the transcellular transport of nanoparticle from the blood to the brain. During the last decades, varieties of nanoparticles that differ in the composition have been developed, and they have the potential application in the diagnostics and therapy of AD. The most common NP formulations that have major impact in the diagnosis and therapy of AD include polymeric NPs (PPs), gold NPs, gadolinium NPs, selenium NPs, protein-based NPs, polysaccharide-based NPs, etc. The goal of this review is to provide discussion of the application of different types of NP formulations in the diagnosis and therapy of AD

Comparison of Efficiency-Based Optimal Load Distribution for Modular SSTs with Biologically Inspired Optimization Algorithms

The battle of currents between AC and DC reignited as a result of the development in the field of power electronics. The efficiency of DC distribution systems is highly dependent on the efficiency of distribution converter, which calls for optimized schemes for the efficiency enhancement of distribution converters. Modular solid-state transformers (SSTs) play a vital role in DC distribution networks and renewable energy systems (RES). This paper deals with efficiency-based load distribution for solid-state transformers (SSTs) in DC distribution networks. The aim is to achieve a set of minimum inputs that are consistent with the output while considering the constraints and efficiency. As the main feature of modularity is associated with a three-stage structure of SSTs, this modular structure is optimized using ant lion optimizer (ALO) and validated by applying it to the EIA (Energy Information Agency) DC distribution network which contains SSTs. In the DC distribution grid, modular SSTs provide the promising conversion of DC power from medium voltage to lower DC range (400 V). The proposed algorithm is simulated in MATLAB and also compared with two other metaheuristic algorithms. The obtained results prove that the proposed method can significantly reduce the input requirements for producing the same output while satisfying the specified constraints

Comparison of Efficiency-Based Optimal Load Distribution for Modular SSTs with Biologically Inspired Optimization Algorithms

The battle of currents between AC and DC reignited as a result of the development in the field of power electronics. The efficiency of DC distribution systems is highly dependent on the efficiency of distribution converter, which calls for optimized schemes for the efficiency enhancement of distribution converters. Modular solid-state transformers (SSTs) play a vital role in DC distribution networks and renewable energy systems (RES). This paper deals with efficiency-based load distribution for solid-state transformers (SSTs) in DC distribution networks. The aim is to achieve a set of minimum inputs that are consistent with the output while considering the constraints and efficiency. As the main feature of modularity is associated with a three-stage structure of SSTs, this modular structure is optimized using ant lion optimizer (ALO) and validated by applying it to the EIA (Energy Information Agency) DC distribution network which contains SSTs. In the DC distribution grid, modular SSTs provide the promising conversion of DC power from medium voltage to lower DC range (400 V). The proposed algorithm is simulated in MATLAB and also compared with two other metaheuristic algorithms. The obtained results prove that the proposed method can significantly reduce the input requirements for producing the same output while satisfying the specified constraints