GDF-15 Attenuates the Epithelium-Mesenchymal Transition and Alleviates TGFß2-Induced Lens Opacity.

Purpose: We sought to evaluate the efficacy of growth differentiation factor (GDF)-15 treatment for suppressing epithelial-mesenchymal transition (EMT) and alleviating transforming growth factor ß2 (TGFß2)-induced lens opacity. Methods: To test whether GDF-15 is a molecule that prevents EMT, we pretreated the culture with GDF-15 in neural progenitor cells, retinal pigment epithelial cells, and lens epithelial cells and then treated with factors that promote EMT, GDF-11, and TGFß2, respectively. To further investigate the efficacy of GDF-15 on alleviating lens opacity, we used mouse lens explant culture to mimic secondary cataracts. We pretreated the lens culture with GDF-15 and then added TGFß2 to develop lens opacity (n = 3 for each group). Western blot and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to measure EMT protein and gene expression, respectively. Results: In cell culture, GDF-15 pretreatment significantly attenuated EMT marker expression in cultured cells induced by treatment with GDF-11 or TGFß2. In the lens explant culture, GDF-15 pretreatment also reduced mouse lens opacity induced by exposure to TGFß2. Conclusions: Our results indicate that GDF-15 could alleviate TGFß2-induced EMT and is a potential therapeutic agent to slow or prevent posterior capsular opacification (PCO) progression after cataract surgery. Translational Relevance: Cataracts are the leading cause of blindness worldwide, with the only current treatment involving surgical removal of the lens and replacement with an artificial lens. However, PCO, also known as secondary cataract, is a common complication after cataract surgery. The development of an adjuvant that slows the progression of PCO will be beneficial to the field of anterior complications.

Understanding and alleviating informal caregiver burden through the development and validation of a caregiver strain index-based model in Taiwan.

BACKGROUND: Quantifying the informal caregiver burden is important for understanding the risk factors associated with caregiver overload and for evaluating the effectiveness of services provided in Long-term Care (LTC). OBJECTIVE: This study aimed to develop and validate a Caregiver Strain Index (CSI)-based score for quantifying the informal caregiver burden, while the original dataset did not fully cover evaluation items commonly included in international assessments. Subsequently, we utilized the CSI-based score to pinpoint key caregiver burden risk factors, examine the initial timing of LTC services adoption, and assess the impact of LTC services on reducing caregiver burden. METHODS: The study analyzed over 28,000 LTC cases in Southern Taiwan from August 2019 to December 2022. Through multiple regression analysis, we identified significant risk factors associated with caregiver burden and examined changes in this burden after utilizing various services. Survival analysis was employed to explore the relationship between adopting the first LTC services and varying levels of caregiver burden. RESULTS: We identified 126 significant risk factors for caregiver burden. The most critical factors included caregiving for other disabled family members or children under the age of three (ß = 0.74, p < 0.001), the employment status of the caregiver (ß = 0.30-0.53, p < 0.001), the frailty of the care recipient (ß = 0.28-0.31, p < 0.001), and the behavioral symptoms of dementia in care recipients (ß = 0.28-2.60, p < 0.05). Generally, caregivers facing higher burdens sought LTC services earlier, and providing home care services alleviated the caregiver's burden. CONCLUSION: This comprehensive study suggests policy refinements to recognize high-risk caregivers better early and provide timely support to improve the overall well-being of both informal caregivers and care recipients.

Vitamin C alleviates hyperglycemic stress in retinal pigment epithelial cells.

BACKGROUND: Retinal pigment epithelial cells (RPECs) are a type of retinal cells that structurally and physiologically support photoreceptors. However, hyperglycemia has been shown to play a critical role in the progression of diabetic retinopathy (DR), which is one of the leading causes of vision impairment. In the diabetic eye, the high glucose environment damages RPECs via the induction of oxidative stress, leading to the release of excess reactive oxygen species (ROS) and triggering apoptosis. In this study, we aim to investigate the antioxidant mechanism of Vitamin C in reducing hyperglycemia-induced stress and whether this mechanism can preserve the function of RPECs. METHODS AND RESULTS: ARPE-19 cells were treated with high glucose in the presence or absence of Vitamin C. Cell viability was measured by MTT assay. Cleaved poly ADP-ribose polymerase (PARP) was used to identify apoptosis in the cells. ROS were detected by the DCFH-DA reaction. The accumulation of sorbitol in the aldose reductase (AR) polyol pathway was determined using the sorbitol detection assay. Primary mouse RPECs were isolated from adult mice and identified by Rpe65 expression. The mitochondrial damage was measured by mitochondrial membrane depolarization. Our results showed that high glucose conditions reduce cell viability in RPECs while Vitamin C can restore cell viability, compared to the vehicle treatment. We also demonstrated that Vitamin C reduces hyperglycemia-induced ROS production and prevents cell apoptosis in RPECs in an AR-independent pathway. CONCLUSIONS: These results suggest that Vitamin C is not only a nutritional necessity but also an adjuvant that can be combined with AR inhibitors for alleviating hyperglycemic stress in RPECs.

Mismatch repair enzymes regulate telomere recombination in Saccharomycescerevisiae.

DNA mismatch repair (MMR) is a crucial mechanism that ensures chromosome stability and prevents the development of various human cancers. Apart from its role in correcting mismatches during DNA replication, MMR also plays a significant role in regulating recombination between non-identical sequences, a process known as homeologous recombination. Telomeres, the protective ends of eukaryotic chromosomes, possess sequences that are not perfectly homologous. While telomerase primarily maintains telomere length in the yeast Saccharomyces cerevisiae, recombination between telomeres becomes a major pathway for length maintenance in cells lacking telomerase. This study investigates the participation of MMR in telomere recombination. Our findings reveal that mutations in MMR genes activate type I recombination. Notably, among the MMR proteins, MutSα (Msh2 and Msh6) and MutLα (Mlh1 and Pms1) exerted the most pronounced effects on telomere recombination. We also found that yeast cells containing simple human telomeric TTAGGG DNA sequences preferentially utilize type II recombination to maintain their telomeres, highlighting the influence of the heterogeneous nature of yeast telomeric sequences on type II recombination. Furthermore, our observations indicate that MMR activity is indispensable for its impact on telomere recombination. Collectively, these results contribute to a more comprehensive understanding of the role of MMR in telomere recombination.

Increased risk of sudden sensorineural hearing loss in patients with cervical spondylosis.

Whether cervical spondylosis (CS) is a risk factor for sudden sensorineural hearing loss (SSNHL) remains unclear. This study used national population-based data to investigate the risk of SSNHL in patients with CS in Taiwan of different ages and sexes. This study used data covering 2 million people in Taiwan, which were obtained from the National Health Insurance Research Database. The data that support the findings of this study are available from National Health Insurance Research Database but restrictions apply to the availability of these data, which were used under license for the current study, and so are not publicly available. Data are however available from the corresponding authors upon reasonable request and with permission of National Health Insurance Research Database. This retrospective cohort study enrolled 91,587 patients with a newly diagnosed CS between January 2000 and December 2018. Case and control cohorts were matched 1:1 according to age, sex, and comorbidities. SSNHL incidence rate and risk were compared between the groups. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). The mean follow-up period was 8.80 (SD = 4.12) and 8.24 (SD = 4.09) years in the CS and control cohorts, respectively. The incidence rate of SSNHL in the CS cohort (85.28 per 100 000 person-years) was 1.49-fold significantly higher than that in the non-CS cohort (57.13 per 100,000 person-years) (95% CI 1.32-1.68, P < .001). After age, sex, and selected comorbidities were adjusted for, CS exhibited an independent risk factor for SSNHL (adjusted HR = 1.52; 95% CI 1.34-1.71, P < .001). An age-stratified analysis in this study demonstrated a strong and highly significant association between CS and SSNHL in patients aged < 35 years (IRR = 2.28, 95% CI 1.18-4.39, P = .013). This large-scale Taiwanese-population-based retrospective study found that CS was associated with an increased risk of SSNHL. Acute hearing loss in patients with CS, particularly at a young age, should be carefully evaluated, and prompt treatment for SSNHL should be initiated.

Predicting Long-Term Care Service Demands for Cancer Patients: A Machine Learning Approach.

BACKGROUND: Long-term care (LTC) service demands among cancer patients are significantly understudied, leading to gaps in healthcare resource allocation and policymaking. OBJECTIVE: This study aimed to predict LTC service demands for cancer patients and identify the crucial factors. METHODS: 3333 cases of cancers were included. We further developed two specialized prediction models: a Unified Prediction Model (UPM) and a Category-Specific Prediction Model (CSPM). The UPM offered generalized forecasts by treating all services as identical, while the CSPM built individual predictive models for each specific service type. Sensitivity analysis was also conducted to find optimal usage cutoff points for determining the usage and non-usage cases. RESULTS: Service usage differences in lung, liver, brain, and pancreatic cancers were significant. For the UPM, the top 20 performance model cutoff points were adopted, such as through Logistic Regression (LR), Quadratic Discriminant Analysis (QDA), and XGBoost (XGB), achieving an AUROC range of 0.707 to 0.728. The CSPM demonstrated performance with an AUROC ranging from 0.777 to 0.837 for the top five most frequently used services. The most critical predictive factors were the types of cancer, patients' age and female caregivers, and specific health needs. CONCLUSION: The results of our study provide valuable information for healthcare decisions, resource allocation optimization, and personalized long-term care usage for cancer patients.

Aldose reductase inhibition decelerates optic nerve degeneration by alleviating retinal microglia activation.

As part of the central nervous system (CNS), retinal ganglion cells (RGCs) and their axons are the only neurons in the retina that transmit visual signals from the eye to the brain via the optic nerve (ON). Unfortunately, they do not regenerate upon injury in mammals. In ON trauma, retinal microglia (RMG) become activated, inducing inflammatory responses and resulting in axon degeneration and RGC loss. Since aldose reductase (AR) is an inflammatory response mediator highly expressed in RMG, we investigated if pharmacological inhibition of AR can attenuate ocular inflammation and thereby promote RGC survival and axon regeneration after ON crush (ONC). In vitro, we discovered that Sorbinil, an AR inhibitor, attenuates BV2 microglia activation and migration in the lipopolysaccharide (LPS) and monocyte chemoattractant protein-1 (MCP-1) treatments. In vivo, Sorbinil suppressed ONC-induced Iba1 + microglia/macrophage infiltration in the retina and ON and promoted RGC survival. Moreover, Sorbinil restored RGC function and delayed axon degeneration one week after ONC. RNA sequencing data revealed that Sorbinil protects the retina from ONC-induced degeneration by suppressing inflammatory signaling. In summary, we report the first study demonstrating that AR inhibition transiently protects RGC and axon from degeneration, providing a potential therapeutic strategy for optic neuropathies.

Flap endonuclease Rad27 cleaves the RNA of R-loop structures to suppress telomere recombination.

The long non-coding telomeric RNA transcript TERRA, in the form of an RNA-DNA duplex, regulates telomere recombination. In a screen for nucleases that affects telomere recombination, mutations in DNA2, EXO1, MRE11 and SAE2 cause severe delay in type II survivor formation, indicating that type II telomere recombination is mediated through a mechanism similar to repairing double-strand breaks. On the other hand, mutation in RAD27 results in early formation of type II recombination, suggesting that RAD27 acts as a negative regulator in telomere recombination. RAD27 encodes a flap endonuclease that plays a role in DNA metabolism, including replication, repair and recombination. We demonstrate that Rad27 suppresses the accumulation of the TERRA-associated R-loop and selectively cleaves TERRA of R-loop and double-flapped structures in vitro. Moreover, we show that Rad27 negatively regulates single-stranded C-rich telomeric DNA circles (C-circles) in telomerase-deficient cells, revealing a close correlation between R-loop and C-circles during telomere recombination. These results demonstrate that Rad27 participates in telomere recombination by cleaving TERRA in the context of an R-loop or flapped RNA-DNA duplex, providing mechanistic insight into how Rad27 maintains chromosome stability by restricting the accumulation of the R-loop structure within the genome.

The Role of Aldose Reductase in Beta-Amyloid-Induced Microglia Activation.

The occurrence of Alzheimer's disease has been associated with the accumulation of beta-amyloid (ß-amyloid) plaques. These plaques activate microglia to secrete inflammatory molecules, which damage neurons in the brain. Thus, understanding the underlying mechanism of microglia activation can provide a therapeutic strategy for alleviating microglia-induced neuroinflammation. The aldose reductase (AR) enzyme catalyzes the reduction of glucose to sorbitol in the polyol pathway. In addition to mediating diabetic complications in hyperglycemic environments, AR also helps regulate inflammation in microglia. However, little is known about the role of AR in ß-amyloid-induced inflammation in microglia and subsequent neuronal death. In this study, we confirmed that AR inhibition attenuates increased ß-amyloid-induced reactive oxygen species and tumor necrosis factor α secretion by suppressing ERK signaling in BV2 cells. In addition, we are the first to report that AR inhibition reduced the phagocytotic capability and cell migration of BV2 cells in response to ß-amyloid. To further investigate the protective role of the AR inhibitor sorbinil in neurons, we co-cultured ß-amyloid-induced microglia with stem cell-induced neurons. sorbinil ameliorated neuronal damage in both cells in the co-culture system. In summary, our findings reveal AR regulation of microglia activation as a novel therapeutic target for Alzheimer's disease.

Cerebral Complications of Snakebite Envenoming: Case Studies.

There are an estimated 5.4 million snakebite cases every year. People with snakebite envenoming suffer from severe complications, or even death. Although some review articles cover several topics of snakebite envenoming, a review of the cases regarding cerebral complications, especially rare syndromes, is lacking. Here, we overview 35 cases of snakebite by front-fanged snakes, including Bothrops, Daboia, Cerastes, Deinagkistrodon, Trimeresurus, and Crotalus in the Viperidae family; Bungarus and Naja in the Elapidae family, and Homoroselaps (rare cases) in the Lamprophiidae family. We also review three rare cases of snakebite by rear-fanged snakes, including Oxybelis and Leptodeira in the Colubridae family. In the cases of viper bites, most patients (17/24) were diagnosed with ischemic stroke and intracranial hemorrhage, leading to six deaths. We then discuss the potential underlying molecular mechanisms that cause these complications. In cases of elapid bites, neural, cardiac, and ophthalmic disorders are the main complications. Due to the small amount of venom injection and the inability to deep bite, all the rear-fanged snakebites did not develop any severe complications. To date, antivenom (AV) is the most effective therapy for snakebite envenoming. In the six cases of viper and elapid bites that did not receive AV, three cases (two by viper and one by elapid) resulted in death. This indicates that AV treatment is the key to survival after a venomous snakebite. Lastly, we also discuss several studies of therapeutic agents against snakebite-envenoming-induced complications, which could be potential adjuvants along with AV treatment. This article organizes the diagnosis of hemotoxic and neurotoxic envenoming, which may help ER doctors determine the treatment for unidentified snakebite.

Evaluation of RevX solution extract as a potential inhibitor of the main protease of SARS-CoV-2-In vitro study and molecular docking.

The main protease (Mpro) of SARS-CoV-2 is a protease necessary for viral polyprotein processing and maturation. Mpro cleaves the polypeptide sequence after the glutamine residues. There is no known cellular protease with this substrate specificity in humans; therefore, it is considered an attractive drug target. Previously, fermented sorghum extract RevX (trademark of Revolutrx INC.) solution significantly alleviated physical decline and complications in a patient with lung adenocarcinoma, suggesting the role of bioactive components in RevX solution. To further explore whether the bioactive components in RevX solution exhibit other biological activities, such as antiviral effects, we investigated its inhibitory effect on the Mpro of SARS-CoV-2 virus. We report herein that the solid extract of the RevX solution exhibits an efficacious Mpro inhibitory activity, with IC50 of 2.07 ± 0.38 µg/mL. Molecular docking of sterol-like components in the RevX extracts identified by MS shows that the three sterol-like molecules can bind to the active region of the GC376-Mpro complex, supporting the structure-function relationship. Combined with its ability to significantly alleviate the body's immunity decline and to inhibit the activity of SARS-CoV-2 Mpro, RevX solution may provide a possible alternative supportive treatment for patients with COVID-19.

Upper Airway Small Cell Carcinoma / Carcinoma de células pequeñas en vías respiratorias superiores

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Palladium-catalyzed cycloisomerizations of diarylacetylenes: synthesis, structures, and physical properties of highly substituted naphthalenes and 8,8 a-dihydrocyclopenta[a]indenes.

Depending on the electronic properties of their substituents, the major products generated by palladium-catalyzed cycloisomerizations of diarylalkynes are either highly substituted 8,8a-dihydrocyclopenta[a]indenes 3 or naphthalenes 4. The structures of these compounds were verified by X-ray crystallographic analysis. Many functional groups tolerated the reaction conditions evaluated in this study. The isotope-labeled experiments indicated that added water has a critical role in forming both classes of compounds. The photophysical and electrochemical properties of cycloadducts 3 and their analogues were systematically studied and compared with computational predictions based on density functional theory. Dihydrocyclopenta[a]indenes 3 in either solid or liquid form display strong luminescence, whereas cyclopenta[a]indene 11 j is practically nonfluorescent. The functional groups directly attached to the backbone of compound 3 significantly influenced physical properties. The steric effect arising from the aryl substituents caused different luminescence phenomena, including aggregation-induced and -enhanced emission.

High-performance p-channel organic semiconducting candidates based on benzo[1,2-k;4,5-k']difluoranthene derivatives.

Orbital promises: Frontier orbital analyses showed that the small lambda(+) value of 8,17-di-n-hexylbenzo[1,2-k;4,5-k']difluoranthene (DH-BDF) is owed to the nonbonding character of the BDF framework. The calculated adiabatic ionic potential and hole mobility indicates that this compound is a p-type air-stable organic field-effect transistor, which promises to be a soluble, stable and high-performance p-type organic semiconductor.