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Tuberculous dactylitis can cause osteomyelitis, which is a rare extrapulmonary manifestation of tuberculosis, often misdiagnosed due to its nonspecific presentation and resemblance to other conditions like neoplasms. A 15-year-old male patient reported to our clinic with a 1-year history of left index finger pain and swelling following a football-related injury. Despite conservative management, the symptoms had progressively worsened over the past few months. Clinical examination revealed deformity and swelling of the middle phalanx, along with induced pain on range of motion. Bacteriological analysis indicated polymorphic nuclear cells and the presence of coagulase-negative Staphylococcus (Staphylococcus hominis). Radiographic evaluation, including x-ray and magnetic resonance imaging, revealed medullary expansion, trabecular thinning, and focal soft tissue swelling. Magnetic resonance imaging displayed extensive soft tissue and bone marrow involvement, raising concerns of a tumor. An open biopsy was performed, yielding unexpected findings of necrotizing and suppurative granulomatous inflammation, strongly suggesting an ongoing infectious process. The subsequent Quantiferon TB Gold Test confirmed tuberculosis infection. Treatment encompassed debridement, synovectomy, and initiation of an antituberculosis regimen. The patient showed significant improvement after treatment. Timely diagnosis and treatment of tuberculous dactylitis are crucial, as highlighted by the patient's positive response to combined surgical and pharmacological intervention, despite initial diagnostic challenges.

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INTRODUCTION: Emotional intelligence (EI) is reported to be associated with better academic performance. However, few studies from the Middle East have assessed whether EI affects academic performance in dental students. The objective of this study was to evaluate the relationship between EI and academic performance in a sample of Saudi Arabian dental students. METHODS: This cross-sectional, questionnaire-based study included first-year to fifth-year dental students and dental interns who were enrolled at King Saud University (KSU) in Riyadh, Saudi Arabia, for the 2023-2024 academic year. Eligible students were invited to complete the self-administered Schutte Self-Report Emotional Intelligence Test (SSEIT) and a demographic questionnaire between October 2023 and January 2024. Academic performance was assessed based on each student's self-reported overall current grade point average (GPA) and was dichotomized into high GPA (between 4.5 and 5) and low GPA (less than 4.5). RESULTS: Of the 437 eligible students, 330 (75.5%) completed the questionnaires. The logistic regression analysis, after sequentially adjusting for various risk factors, showed significantly better academic performance for those who had higher EI (OR=2.6, P-value=0.02). CONCLUSION: The findings of this study suggest a significant association between EI and academic success. EI is essential for improving academic performance in dental education.

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Introduction: Gait analysis, an expanding research area, employs non-invasive sensors and machine learning techniques for a range of applications. In this study, we investigate the impact of cognitive decline conditions on gait performance, drawing connections between gait deterioration in Parkinson's Disease (PD) and healthy individuals dual tasking. Methods: We employ Explainable Artificial Intelligence (XAI) specifically Layer-Wise Relevance Propagation (LRP), in conjunction with Convolutional Neural Networks (CNN) to interpret the intricate patterns in gait dynamics influenced by cognitive loads. Results: We achieved classification accuracies of 98% F1 scores for PD dataset and 95.5% F1 scores for the combined PD dataset. Furthermore, we explore the significance of cognitive load in healthy gait analysis, resulting in robust classification accuracies of 90% ± 10% F1 scores for subject cognitive load verification. Our findings reveal significant alterations in gait parameters under cognitive decline conditions, highlighting the distinctive patterns associated with PD-related gait impairment and those induced by multitasking in healthy subjects. Through advanced XAI techniques (LRP), we decipher the underlying features contributing to gait changes, providing insights into specific aspects affected by cognitive decline. Discussion: Our study establishes a novel perspective on gait analysis, demonstrating the applicability of XAI in elucidating the shared characteristics of gait disturbances in PD and dual-task scenarios in healthy individuals. The interpretability offered by XAI enhances our ability to discern subtle variations in gait patterns, contributing to a more nuanced comprehension of the factors influencing gait dynamics in PD and dual-task conditions, emphasizing the role of XAI in unraveling the intricacies of gait control.

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Burkitt lymphoma is an aggressive B-cell non-Hodgkin lymphoma (NHL). Primary CNS lymphoma (PCNSL) is a rare disease, and the subtype of Burkitt lymphoma presenting as a sole CNS lesion is an even rarer diagnosis. Acute sudden blindness is a rare presenting symptom of PCNSL or NHL in general. We present an interesting case of a four-year-old boy with dysmorphic features whose visual examination showed a sudden bilateral loss of vision. There was bilateral eye proptosis and complete ptosis. Extraocular muscles were fixed straight. The pupils were fixed and mid dilated bilaterally and there was grade 3/4 papilledema in both eyes. Neuroimaging showed a mass in the base of the skull, extending to orbits and sinuses. A cervical biopsy of the enlarged lymph nodes was taken and a histopathological diagnosis of Burkitt lymphoma was made. Genetic analysis showed a GNB1 mutation, and the patient was diagnosed with Kabuki syndrome by a pediatrician, based on characteristic dysmorphic features. Treatment with steroids and chemotherapy was initiated.

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Introduction: Breast cancer (BC) is the most common cancer affecting women in the United States. Ductal carcinoma in situ (DCIS) is the earliest identifiable pre-invasive BC lesion. Estimates show that 14 to 50% of DCIS cases progress to invasive BC. Methods: Our objective was to identify nuclear matrix proteins (NMP) with specifically altered expression in DCIS and later stages of BC compared to non-diseased breast reduction mammoplasty and a contralateral breast explant culture using mass spectrometry and RNA sequencing to accurately identify aggressive DCIS. Results: Sixty NMPs were significantly differentially expressed between the DCIS and non-diseased breast epithelium in an isogenic contralateral pair of patient-derived extended explants. Ten of the sixty showed significant mRNA expression level differences that matched the protein expression. These 10 proteins were similarly expressed in non-diseased breast reduction cells. Three NMPs (RPL7A, RPL11, RPL31) were significantly upregulated in DCIS and all other BC stages compared to the matching contralateral breast culture and an unrelated non-diseased breast reduction culture. RNA sequencing analyses showed that these three genes were increasingly upregulated with BC progression. Finally, we identified three NMPs (AHNAK, CDC37 and DNAJB1) that were significantly downregulated in DCIS and all other BC stages compared to the isogenically matched contralateral culture and the non-diseased breast reduction culture using both proteomics and RNA sequencing techniques. Discussion: These genes should form the basis of, or contribute to, a molecular diagnostic panel that could identify DCIS lesions likely to be indolent and therefore not requiring aggressive treatment.

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PURPOSE: Inguinal hernias lead to several potentially fatal complications such as strangulation. Assessing the prevalence, risk factors, and beliefs of a population is essential to develop appropriate preventive strategies. This study investigated the prevalence, risk factors, and awareness of inguinal hernia in the adult population of Saudi Arabia. METHODS: This cross-sectional study enrolled 461 adults aged between 18 and 60 years after excluding those aged <18 and >60 years. This study was conducted in five regions of Saudi Arabia (north, west, central, south, and east). A pre-tested questionnaire was used to collect data on the prevalence, perception, and awareness of the participants. Multivariate regression analysis was used to identify risk factors for inguinal hernia. RESULTS: The study revealed that most participants were men n=262 (56.8%), aged between 18 and 25 years n=241 (52.3%), were single n=278 (60.3%), had a bachelor's degree n=225 (48.8%) and earned less than 50,000 Saudi Riyals annually n=285 (61.8%). Most participants resided in urban areas n=366 (79.4%) with their parents n=230 (49.9%). The prevalence of inguinal hernias in adults was low (5.2%). Our results indicated a significant association between family history of inguinal hernia, chronic cough, bronchial asthma, smoking, and inguinal hernia (p < 0.001). Young adults and undergraduates displayed significantly low awareness of inguinal hernias (p < 0.001). CONCLUSION: Family history of inguinal hernia, chronic cough, bronchial asthma, and smoking were factors associated with inguinal hernia. Low awareness levels were observed among young undergraduates, with a moderate overall level of awareness.

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Water scarcity and droughts are among the most challenging issues worldwide, particularly in arid and semi-arid regions like Saudi Arabia. Date palm (Phoenix dactylifera L.), a major crop in Saudi Arabia, is being significantly affected by water scarcity, soil salinity, and desertification. Alternative water sources are needed to conserve freshwater resources and increase date palm production in Saudi Arabia. On the other hand, Saudi Arabia has a significant number of aquaculture farms that generate substantial amounts of wastewater, which can be utilized as an alternative source of irrigation. Therefore, this study aimed to assess the potential of aquaculture wastewater as an alternative irrigation source for date palm orchards. Aquaculture wastewater was collected from 12 different farms (Al-Kharj, Al-Muzahmiya, and Al-Qassim regions, Saudi Arabia) and its quality was analyzed. The impacts of aquaculture wastewater irrigation on soil quality, nutrient availability, nutrient status of date palm trees, and dates fruit quality were assessed in comparison to source water (freshwater) irrigation at Al-Kharj, Al-Muzahmiya, and Al-Qassim regions. The water quality analyses showed higher salinity (EC = 3.31 dSm-1) in farm Q3, while all other farms demonstrated no salinity, sodicity, or alkalinity hazards. Moreover, the aquaculture wastewater irrigation increased soil available P, K, NO3--N, and NH4+-N by 49.31%, 21.11%, 33.62%, and 52.31%, respectively, compared to source water irrigation. On average, date palm fruit weight, length, and moisture contents increased by 26%, 23%, and 43% under aquaculture wastewater irrigation compared to source water irrigation. Further, P, K, Fe, Cu, and Zn contents in date palm leaf were increased by 19.35%, 34.17%, 37.36%, 38.24%, and 45.29%, respectively, under aquaculture wastewater irrigation compared to source water irrigation. Overall, aquaculture wastewater irrigation significantly enhanced date palm plant growth, date palm fruit quality, and soil available nutrients compared to freshwater irrigation. It was concluded that aquaculture wastewater can be used as an effective irrigation source for date palm farms as it enhances soil nutrient availability, date palm growth, and date fruit yield and quality. The findings of this study suggest that aquaculture wastewater could be a viable alternative for conserving freshwater resources and increase date palm production in Saudi Arabia.

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Intracranial meningiomas are the most common primary brain tumors, typically presenting with well-defined imaging characteristics. This case report focuses on a 56-year-old female patient who was referred due to a history of head trauma and an incidental space-occupying finding to investigate the atypical imaging appearances of intracranial meningiomas, focusing on a specific case with distinct radiological findings. Meningiomas are commonly associated with specific radiological features, such as contrast enhancement, dural tail, and hyperostosis. However, this particular case exhibited atypical imaging characteristics that raised concerns about the underlying tumor type. In-depth analysis and subsequent histopathological examination revealed a World Health Organization (WHO) grade II atypical meningioma. This variant of meningioma demonstrated increased cellularity, nuclear atypia, and a high mitotic index, indicating more aggressive tumor behavior. The study highlights the importance of recognizing atypical imaging appearances in meningiomas, as they may indicate higher-grade tumors with a potentially different clinical course and management approach. Accurate identification of these atypical features can contribute to improved diagnostic accuracy and guide appropriate surgical decision-making for patients with intracranial meningiomas.

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BACKGROUND: Academic achievement is essential for all students seeking a successful career. Studying habits and routines is crucial in achieving such an ultimate goal. OBJECTIVES: This study investigates the association between study habits, personal factors, and academic achievement, aiming to identify factors that distinguish academically successful medical students. METHODS: A cross-sectional study was conducted at the College of Medicine, King Saud University, Riyadh, Saudi Arabia. The participants consisted of 1st through 5th-year medical students, with a sample size of 336. The research team collected study data using an electronic questionnaire containing three sections: socio-demographic data, personal characteristics, and study habits. RESULTS: The study results indicated a statistically significant association between self-fulfillment as a motivation toward studying and academic achievement (p = 0.04). The results also showed a statistically significant correlation between recalling recently memorized information and academic achievement (p = 0.05). Furthermore, a statistically significant association between preferring the information to be presented in a graphical form rather than a written one and academic achievement was also found (p = 0.03). Students who were satisfied with their academic performance had 1.6 times greater chances of having a high-grade point average (OR = 1.6, p = 0.08). CONCLUSION: The results of this study support the available literature, indicating a correlation between study habits and high academic performance. Further multicenter studies are warranted to differentiate between high-achieving students and their peers using qualitative, semi-structured interviews. Educating the students about healthy study habits and enhancing their learning skills would also be of value.

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Antibiotic resistance is a major problem and a major global health concern. In total, there are 16 million deaths yearly from infectious diseases, and at least 65% of infectious diseases are caused by microbial communities that proliferate through the formation of biofilms. Antibiotic overuse has resulted in the evolution of multidrug-resistant (MDR) microbial strains. As a result, there is now much more interest in non-antibiotic therapies for bacterial infections. Among these revolutionary, non-traditional medications is quorum sensing inhibitors (QSIs). Bacterial cell-to-cell communication is known as quorum sensing (QS), and it is mediated by tiny diffusible signaling molecules known as autoinducers (AIs). QS is dependent on the density of the bacterial population. QS is used by Gram-negative and Gram-positive bacteria to control a wide range of processes; in both scenarios, QS entails the synthesis, identification, and reaction to signaling chemicals, also known as auto-inducers. Since the usual processes regulated by QS are the expression of virulence factors and the creation of biofilms, QS is being investigated as an alternative solution to antibiotic resistance. Consequently, the use of QS-inhibiting agents, such as QSIs and quorum quenching (QQ) enzymes, to interfere with QS seems like a good strategy to prevent bacterial infections. This review sheds light on QS inhibition strategy and mechanisms and discusses how using this approach can aid in winning the battle against resistant bacteria.

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Lung diseases are almost invariably heterogeneous and progressive, making it imperative to capture temporally and spatially explicit information to understand the disease initiation and progression. Imaging the lung with MRI-particularly in the preclinical setting-has historically been challenging because of relatively low lung tissue density, rapid cardiac and respiratory motion, and rapid transverse (T2*) relaxation. These limitations can largely be mitigated using ultrashort-echo-time (UTE) sequences, which are intrinsically robust to motion and avoid significant T2* decay. A significant disadvantage of common radial UTE sequences is that they require inefficient, center-out k-space sampling, resulting in long acquisition times relative to conventional Cartesian sequences. Therefore, pulmonary images acquired with radial UTE are often undersampled to reduce acquisition time. However, undersampling reduces image SNR, introduces image artifacts, and degrades true image resolution. The level of undersampling is further increased if offline gating techniques like retrospective gating are employed, because only a portion (∼40-50%) of the data is used in the final image reconstruction. Here, we explore the impact of undersampling on SNR and T2* mapping in mouse lung imaging using simulation and in-vivo data. Increased scatter in both metrics was noticeable at around 50% sampling. Parenchymal apparent SNR only decreased slightly (average decrease âˆ¼ 1.4) with as little as 10% sampling. Apparent T2* remained similar across undersampling levels, but it became significantly increased (p < 0.05) below 80% sampling. These trends suggest that undersampling can generate quantifiable, but moderate changes in the apparent value of T2*. Moreover, these approaches to assess the impact of undersampling are straightforward to implement and can readily be expanded to assess the quantitative impact of other MR acquisition and reconstruction parameters.

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BACKGROUND: The COVID-19 pandemic has had a significant impact globally, and understanding the relationship between inflammatory markers and disease progression is crucial for effective management. This retrospective study aimed to examine the association between various inflammatory markers, such as C-reactive protein (CRP), the erythrocyte sedimentation rate (ESR), lactate dehydrogenase (LDH), D-dimer, ferritin, and procalcitonin (PCT), and the characteristics of disease progression and outcomes in individuals affected by COVID-19. METHODS: This study collected raw data from 470 patients who tested positive for SARS-CoV-2 using RT-PCR. RESULTS: The logistic regression analysis revealed that elevated LDH levels were associated with male gender, ICU admission, low oxygen saturation (O2 < 93%), the need for mechanical ventilation, death, and the presence of lung infiltrates. Higher D-dimer levels were associated with older age, diabetes mellitus, cardiac disease, and low oxygen saturation. Ferritin levels were significantly associated with older age, ICU admission, low oxygen saturation, mechanical ventilation, and lung infiltrates. In contrast, CRP was only significant regarding lung infiltrates and procalcitonin levels were not significantly associated with any of the examined factors. CONCLUSION: This study highlights the importance of monitoring key inflammatory markers, such as LDH, D-dimer, and ferritin, as they are significantly associated with the severity of COVID-19 illness. These findings can inform clinical decision-making and guide the development of targeted interventions to improve patient outcomes.

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In this study, we enhanced the corrosion and microbial resistance of aluminum 7075 alloys by applying a thin layer of alumina through plasma electrolytic oxidation (PEO) in an alkali-silicate electrolyte. In addition, the influence of film sealing on coated aluminum alloy 7075 was studied in detail, specifically in oil and water at 100 °C after treatment. The surface and cross-sectional morphology, element composition, and phase composition of the PEO coatings were characterized by using scanning electron microscopy (SEM) assisted with energy-dispersive X-ray spectrometry (EDS) and X-ray diffraction (XRD), respectively. The corrosion resistance of the coating on AA7075 PEO was evaluated before and after post-treatment using hot water and hump oil at 100 °C. This assessment was conducted by using various electrochemical techniques, including open-circuit potential (OCP), linear polarization resistance (LPR), potentiodynamic polarization scan (PD), electrochemical impedance spectroscopy (EIS), and cyclic potentiodynamic scan (CPS). The results showed that the corrosion resistance of the AA7075 alloy was significantly improved after the PEO coating. The AA7075 + SF, among all of the examined alloys, exhibited superior corrosion properties, due to its fat sealing. This is probably due to the formation of a mixed fatty acid layer from oil on the surface of the AA7075 PEO, which synthesizes a hydrophobic layer. Interestingly, the samples treated with PEO showed a great resistance to microbial growth.

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BACKGROUND: Alzheimer's disease (AD) affects approximately 50 million people globally and is expected to triple by 2050. Arctiin is a lignan found in the Arctium lappa L. plant. Arctiin possesses anti-proliferative, antioxidative and anti-adipogenic. OBJECTIVES: We aimed to explore the potential therapeutic effects of Arctiin on rats with AD by evaluating the expression of TLR4, NLRP3, STAT3, TGF-ß, cyclin D1, and CDK2. METHODS: AD was induced in rats by administering 70 mg/kg of aluminum chloride through intraperitoneal injection daily for six weeks. After inducing AD, some rats were treated with 25 mg/kg of Arctiin daily for three weeks through oral gavage. Furthermore, to examine the brain tissue structure, hippocampal sections were stained with hematoxylin/eosin and anti-TLR4 antibodies. The collected samples were analyzed for gene expression and protein levels of TLR4, NLRP3, STAT3, TGF-ß, cyclin D1, and CDK2. RESULTS: In behavioral tests, rats showed a significant improvement in their behavior when treated with Arctiin. Microimages stained with hematoxylin/eosin showed that Arctiin helped to improve the structure and cohesion of the hippocampus, which was previously impaired by AD. Furthermore, Arctiin reduced the expression of TLR4, NLRP3, STAT3, TGF-ß, cyclin D1, and CDK2. CONCLUSION: Arctiin can enhance rats' behavior and structure of the hippocampus in AD rats. This is achieved through its ability to reduce the expression of both TLR4 and NLRP3, hence inhibiting the inflammasome pathway. Furthermore, Arctiin can improve tissue fibrosis by regulating STAT3 and TGF-ß. Lastly, it can block the cell cycle proteins cyclin D1 and CDK2.

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Background: Nomophobia is a public health issue that involves the fear of being without a mobile phone. The study aimed to estimate the prevalence of nomophobia and its relation to psychological factors, including depression and insomnia, among the general population in Makkah Province and Al-Madinah Province, Saudi Arabia. Methods: This analytical cross-sectional study was conducted and data were obtained through a self-administered online questionnaire using the Patient Health Questionnaire-2 (PHQ-2) for depression, the Nomophobia Questionnaire (NMP-Q), and Insomnia Severity Index (ISI). Results: A total of 1022 participants completed the questionnaire. The prevalence of nomophobia was 96.7%. Moderate nomophobia was prevalent (47.8%). Based on the PHQ-2, possible depression was identified in 47.3% of the respondents. 37.1% had sub-threshold insomnia. In terms of personal psychiatric history, the most common mental disorders in the participants included generalized anxiety disorder (9.9%) and major depressive disorder (9.7%). 61.6% of them used mobile devices for more than four hours per day. Conclusion: Nomophobia is prevalent in the Makkah and Al-Madinah provinces in Saudi Arabia. The risk of nomophobia was significantly higher for participants who spent more hours using mobile devices, those with possible depression, and those having irritable bowel syndrome.

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This study presents a rare case of pure choriocarcinoma (PCC) with metastasis to the gastrointestinal tract in a 52-year-old male with a history of mixed germ cell tumor in remission. Despite negative oncology surveillance imaging, serum marker monitoring, and a recent colonoscopy, the patient presented with new-onset melena and dysphagia, leading to further diagnostic evaluation. Endoscopic examination revealed an ulcerated duodenal mass, and a computer tomography (CT)-guided liver biopsy confirmed metastatic PCC. This case highlights the aggressive nature of PCC and the importance of considering gastrointestinal metastasis in patients with atypical symptoms, even when in apparent remission.

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Aberrant activation of the NLRP3 inflammasome is recognized to induce a chronic inflammatory response in the liver, ultimately leading to hepatic fibrosis. HSP90 is suggested to regulate NLRP3 activation and its downstream signaling. This study is the first to explore the potential therapeutic role of pimitespib in mitigating liver fibrosis in rats. The results of the study revealed that pimitespib effectively suppressed hepatic inflammation and fibrogenesis by modulating HSP90's control over the NFκB/NLRP3/caspase-1 axis. In vitro experiments demonstrated that pimitespib reduced LDH levels and increased hepatocyte survival, whereas in vivo, it prolonged the survival of rats with hepatic fibrosis. Additionally, pimitespib exhibited improvements in the function and microscopic characteristics of rat livers. Pimitespib effectively inhibited NFκB, which serves as the priming signal for NLRP3 activation. Pimitespib's inhibitory effect on NLRP3, identified as an HSP90 client protein, plays a central role in the observed anti-fibrotic effect. The simultaneous inhibition of both priming and activation signals of NLRP3 by pimitespib led to a reduction in caspase-1 activity and subsequent suppression of the N-terminal fragment of gasdermin D, ultimately constraining hepatocyte pyroptotic cell death. These diverse effects were associated with a decrease in the transcription of inflammatory mediators IL-1ß, IL-18, and TNF-α, as well as the fibrogenic mediators TGF-ß, TIMP-1, PDGF-BB, and Col1a1. Moreover, pimitespib induced the expression of HSP70, which could further contribute to the repression of fibrosis development. In summary, our findings provide an evolutionary perspective on managing liver fibrosis, positioning pimitespib as a promising candidate for anti-inflammatory and antifibrotic therapy.

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BACKGROUND: This study systematically designed and optimised a transniosomal formulation containing embelin for skin cancer management. The transniosomes were developed using a rotary evaporation method and then optimised using a Box-Behnken design. RESULTS: The optimized embelin-loaded transniosomes (Opt-EMB-TNs) exhibited a vesicle size of 149.01 nm, polydispersity index of 0.184, a zeta potential of -21.14 mV, an entrapment efficiency of 75.6 ± 0.65%, drug loading of 3.36 ± 0.03% and drug release of 80.88 ± 2.55%. The antioxidant potential of Opt-EMB-TNs was found to be 88.54% when compared to standard ascorbic acid. Dermatokinetic studies showed a greater drug deposition in targeted skin areas with Opt-EMB-TN gel compared to the embelin conventional gel (EMB-CF gel). In addition, the penetration depth study of the skin sample revealed that the transniosomal gel containing rhodamine B dye exhibited higher penetration than that of the rhodamine B dye containing hydroalcoholic solution. The efficacy of Opt-EMB-TNs for skin cancer was confirmed by cytotoxicity assay against the B16F10 melanoma cell line. CONCLUSION: The study concluded that the Opt-EMB-TN gel formulation is a promising and effective topical treatment for skin cancer, demonstrating significant potential for further development and clinical application. © 2024 Society of Chemical Industry.

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Branched-chain amino acids (BCAAs) play vital roles in metabolic and physiological processes, with their catabolism initiated by two branched-chain aminotransferase isozymes: cytosolic (BCATc) and mitochondrial (BCATm). These enzymes have tissue and cell-specific compartmentalization and are believed to shuttle metabolites between cells and tissues. Although their expression and localization have been established in most tissues, ocular tissues remain unknown. In this study, we used immunohistochemical analyses to investigate the expression and localization of BCAT enzymes in the normal eye tissues. As expected, BCATc was highly expressed in the neuronal cells of the retina, particularly in the ganglion cell layers, inner nuclear layer, and plexiform layer, with little to no expression in Müller cells. BCATc was also present in the cornea, retinal pigment epithelium (RPE), choroid, ciliary body, and iris but not in the lens. In contrast, BCATm was expressed across all ocular tissues, with strong expression in the Muller cells of the retina, the endothelial and epithelial layers of the cornea, the choroid and iris, and the epithelial cells at the lens's front. The extensive expression and distribution of BCAT isozymes in the ocular tissue, suggests that BCAA transamination is widespread in the eye, potentially aiding in metabolite transport between ocular tissues. The findings provide new insights into the physiological role of BCATs in the eye, particularly within the neuronal retina.

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RATIONALE AND OBJECTIVES: Hyperpolarized xenon (129Xe) MRI is a noninvasive method to assess pulmonary structure and function. To measure lung microstructure, diffusion-weighted imaging-commonly the apparent diffusion coefficient (ADC)-can be employed to map changes in alveolar-airspace size resulting from normal aging and pulmonary disease. However, low signal-to-noise ratio (SNR) decreases ADC measurement certainty, and biases ADC to spuriously low values. Further, these challenges are most severe in regions of the lung where alveolar simplification or emphysematous remodeling generate abnormally high ADCs. Here, we apply Global Local Higher Order Singular Value Decomposition (GLHOSVD) denoising to enhance image SNR, thereby reducing uncertainty and bias in diffusion measurements. MATERIALS AND METHODS: GLHOSVD denoising was employed in simulated images and gas phantoms with known diffusion coefficients to validate its effectiveness and optimize parameters for analysis of diffusion-weighted 129Xe MRI. GLHOSVD was applied to data from 120 subjects (34 control, 39 cystic fibrosis (CF), 27 lymphangioleiomyomatosis (LAM), and 20 asthma). Image SNR, ADC, and distributed diffusivity coefficient (DDC) were compared before and after denoising using Wilcoxon signed-rank analysis for all images. RESULTS: Denoising significantly increased SNR in simulated, phantom, and in-vivo images, showing a greater than 2-fold increase (p < 0.001) across diffusion-weighted images. Although mean ADC and DDC remained unchanged (p > 0.05), ADC and DDC standard deviation decreased significantly in denoised images (p < 0.001). CONCLUSION: When applied to diffusion-weighted 129Xe images, GLHOSVD improved image quality and allowed airspace size to be quantified in high-diffusion regions of the lungs that were previously inaccessible to measurement due to prohibitively low SNR, thus providing insights into disease pathology.