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1.
Int J Immunogenet ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809236

RESUMO

Vitamin D deficiency is widespread and poses a significant health concern, as emerging research links it to allergic diseases owing to its immunomodulatory functions. The optimal functioning of vitamin D and its activation depend on its nuclear receptor, vitamin D receptor (VDR). Genetic variants of VDR have been explored as potential factors in autoimmune and allergic diseases, with limited studies on their association with allergic rhinitis (AR). The present investigation aims to analyse the role of three VDR genetic variants - TaqI, FokI and BsmI - in AR susceptibility and their impact on VDR mRNA and serum vitamin D levels. A total of 550 subjects, consisting of 250 AR cases and 300 age- and gender-matched controls, underwent genotyping by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). VDR mRNA and vitamin D levels were determined by quantitative real-time PCR and chemiluminescence, respectively. Although TaqI did not exhibit significant differences, FokI demonstrated a noteworthy association with AR, particularly with the CC genotype (odds ratio [OR]: 3.34; confidence interval [CI]: 1.79-6.23). Similarly, BsmI revealed an increased risk for AR, with the GA + AA genotypes showing a 2.2-fold elevated risk (OR: 2.20; CI: 1.53-3.16). VDR mRNA expression was threefold lower in AR patients (p < .0001), accompanied by reduced serum vitamin D levels (p < .0001). In addition, CC (p = .01) and AA (p = .02) genotypes of FokI and BsmI were associated with reduced VDR mRNA levels, whereas TaqI showed no such association. Similarly, heterozygous genotypes of TaqI and FokI, as well as homozygous AA of BsmI, correlated with lower serum vitamin D levels (p < .001). This study emphasizes the intricate relationship among VDR genetic variations, altered VDR activity, immune modulation and vitamin D metabolism in AR. Further research involving diverse populations is crucial for confirming and generalizing these findings, paving the way for personalized therapeutic interventions in vitamin D-related disorders.

2.
Am J Emerg Med ; 82: 37-41, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38781784

RESUMO

BACKGROUND: Emergency Department (ED) Observation Units (OU) can provide safe, effective care for low risk patients with intracranial hemorrhages. We compared current ED OU use for patients with subdural hematomas (SDH) to the validated Brain Injury Guidelines (BIG) to evaluate the potential impact of implementing this risk stratification tool. METHODS: Retrospective cohort of patients ≥18 years old with SDH of any cause from 2014 to 2020 to evaluate for potential missed OU cases. Missed OU cases were defined as patients with an initial Glasgow Coma Score (GCS) of 15 with hospital length of stays (LOS) <2 days, who did not meet the composite outcome and were not cared for in the OU or discharged from the ED. Composite outcome included in-hospital death or transition to hospice care, neurosurgical intervention, GCS decline, and worsening SDH size. Secondary outcomes were whether application of BIG would increase ED OU use or reduce CT use. RESULTS: 264 patients met inclusion criteria over 5.3 year study timeframe. Mean age was 61 years (range 19-93) and 61.4% were male. SDH were traumatic in 76.9% and 60.2% of the cohort had additional injuries. The admission rate was 81.4% (n = 215). Fourteen (6.5%) missed OU cases were identified (2.6/year). Retrospective application of BIG resulted in 82.6% (n = 217) at BIG 3, 10.2% (n = 27) at BIG 2 and 7.6% (n = 20) at BIG 1. Application of BIG would not have decreased admission rates (82.6% BIG 3) and BIG 1 and 2 admissions were often for medical co-morbidities. The composite outcome was met in 50% of BIG 3, 22% of BIG 2, and no BIG 1 patients. CONCLUSION: In a level 1 trauma center with an established observation unit, current clinical care processes missed very few patients who could be discharged or placed in ED OU for SDH. Hospital admissions in BIG 1/2 were driven by co-morbidities and/or injuries, limiting applicability of BIG to this population.

4.
Ann Neurol ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738750

RESUMO

OBJECTIVE: For stroke patients with unknown time of onset, mismatch between diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) can guide thrombolytic intervention. However, access to MRI for hyperacute stroke is limited. Here, we sought to evaluate whether a portable, low-field (LF)-MRI scanner can identify DWI-FLAIR mismatch in acute ischemic stroke. METHODS: Eligible patients with a diagnosis of acute ischemic stroke underwent LF-MRI acquisition on a 0.064-T scanner within 24 h of last known well. Qualitative and quantitative metrics were evaluated. Two trained assessors determined the visibility of stroke lesions on LF-FLAIR. An image coregistration pipeline was developed, and the LF-FLAIR signal intensity ratio (SIR) was derived. RESULTS: The study included 71 patients aged 71 ± 14 years and a National Institutes of Health Stroke Scale of 6 (interquartile range 3-14). The interobserver agreement for identifying visible FLAIR hyperintensities was high (κ = 0.85, 95% CI 0.70-0.99). Visual DWI-FLAIR mismatch had a 60% sensitivity and 82% specificity for stroke patients <4.5 h, with a negative predictive value of 93%. LF-FLAIR SIR had a mean value of 1.18 ± 0.18 <4.5 h, 1.24 ± 0.39 4.5-6 h, and 1.40 ± 0.23 >6 h of stroke onset. The optimal cut-point for LF-FLAIR SIR was 1.15, with 85% sensitivity and 70% specificity. A cut-point of 6.6 h was established for a FLAIR SIR <1.15, with an 89% sensitivity and 62% specificity. INTERPRETATION: A 0.064-T portable LF-MRI can identify DWI-FLAIR mismatch among patients with acute ischemic stroke. Future research is needed to prospectively validate thresholds and evaluate a role of LF-MRI in guiding thrombolysis among stroke patients with uncertain time of onset. ANN NEUROL 2024.

5.
RSC Adv ; 14(22): 15791-15803, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38752155

RESUMO

Because of their distinctive characteristics, ferroelectric perovskites are considered among the most potent and auspicious candidates for energy storage and pulsed power devices. But their energy storage properties and switching capabilities need to be further enhanced which can be done by substitutions of appropriate cations. Hence, a series of lead-free Ba1-xSrxNiO3 (x = 0.00, 0.33, 0.67, and 1.00) ceramics was fabricated using a sol-gel auto combustion technique. Rietveld's refinement of X-ray diffraction plots verified the complete development of the required hexagonal perovskite structure. Scanning electron microscopy images revealed a gradual increase in average grain sizes and agglomeration with the increase in Sr-content. Moreover, the existence of all the constituent elements exactly in proportion to their stoichiometric ratios was verified by energy dispersive X-ray spectroscopy. The characteristic parameters of ferroelectric materials such as ferroelectric response, electrical conductivity, and switching charge density were also determined. The P-E loops indicated that with the increase in Sr-content, the coercive field, remanent polarization, and maximum polarization all decreased gradually, but the recoverable energy density (Wrec) increased as the loops became slimmer. The maximum value of Wrec was found in the Ba0.33Sr0.67NiO3 sample. Moreover, SrNiO3 exhibited minimum energy loss with the highest efficiency of ∼47.21%. The existence of a current barrier in all the samples was proved from the low leakage current values (∼10-7 A). In addition, the pure SrNiO3 showed a low electrical conductivity and minimum value of switching charge density. All these findings make SrNiO3 a promising candidate for fast switching and energy storage applications.

6.
Discov Oncol ; 15(1): 108, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587694

RESUMO

BACKGROUND: Fragile histidine triad (FHIT) has been documented to play a vital role in various cancers including acute lymphoblastic leukemia (ALL). Keeping in view the plausible role of FHIT gene, we aimed to examine DNA promoter hypermethylation and mRNA expression in ALL cases in Kashmir (North India). METHODS: A total of 66 cases of ALL were analyzed for FHIT mRNA expression and promoter methylation by qRT-PCR and Methylation Specific-PCR (MS-PCR) respectively. RESULTS: FHIT mRNA expression showed significantly decreased expression in ALL cases with mean fold change of 9.24 ± 5.44 as compared to healthy controls (p = 0.01). The pattern of FHIT deregulation in ALL cases differed significantly between decreased and increased expression (p < 0.0001). A threefold decreased expression was observed in 75% of ALL cases than healthy controls (- 3.58 ± 2.32). ALL patients with FHIT gene promoter hypermethylation presented significantly higher in 80% (53/66) of cases (p = 0.0005). The association of FHIT gene hypermethylation and its subsequent expression showed FHIT mRNA expression as significantly lower in ALL cases with hypermethylation (p = 0.0008). B-ALL cases exhibited a highly significant association between the methylation pattern and its mRNA expression (p = 0.000). In low range WBC group, a significant association was found between increased expression (26%) of the cases and methylated (4%)/unmethylated group 86% (p = 0.0006). CONCLUSION: The present study conclude that FHIT gene hypermethylation and its altered expression may be linked in the pathogenesis of ALL and provide an evidence for the role of FHIT in the development of ALL.

7.
Cureus ; 16(3): e55902, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38595903

RESUMO

Gastric cancer stands as a significant global health concern, particularly prevalent in Eastern Asia, with high mortality rates urging urgent attention and research efforts. This article comprehensively explores the epidemiology, anatomy, risk factors, pathophysiology, clinical presentation, diagnosis, staging, treatment modalities, prevention strategies, and survival rates associated with gastric cancer. Notably, Helicobacter pylori infection, dietary choices, and intricate stomach anatomy play pivotal roles in disease development. Early detection, utilizing staging, grading, and genetic testing for personalized treatment approaches is emphasized. Treatment modalities encompass surgery, chemotherapy, radiation therapy, targeted therapy, and immunotherapy. Prevention strategies involve lifestyle changes, screening, and genetic counseling. Survival rates vary by stage, highlighting the need for individualized care. In conclusion, a collaborative global effort is essential to address the impact of gastric cancer and improve outcomes.

8.
Dalton Trans ; 53(17): 7477-7497, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38596884

RESUMO

In order to quench the thirst for efficient energy storage devices, a novel praseodymium-based state-of-the-art three-dimensional metal-organic framework (MOF), {[Pr(pdc)2]Me2NH2}n (YK-1), has been synthesized by using a simple solvothermal method employing a readily available ligand. YK-1 was characterised by single-crystal XRD and crystallographic analysis. The electrochemical measurements of YK-1 show that it exhibits a specific capacitance of 363.5 F g-1 at a current density of 1.5 A g-1 with 83.8% retention after 5000 cycles. In order to enhance its electrochemical performance for practical application, two composites of YK-1 with graphene oxide (GO) and functionalised multi-walled carbon nanotubes (FCNTs), namely YK-1@GO and YK-1@FCNT, were fabricated by employing a facile ultrasonication technique. The as-synthesized MOF and the composites were characterized by PXRD, FTIR, SEM, and TEM techniques. YK-1@GO and YK-1@FCNT offer enhanced specific capacitances of 488.2 F g-1 and 730.2 F g-1 at the same current density with 93.8% and 97.7% capacity retention after 5000 cycles, respectively (at 16 A g-1). Fascinated by the outstanding results shown by YK-1@FCNT, a symmetric supercapacitor device (SSC) based on it was fabricated. The assembled SSC achieved a remarkable energy density (87.6 W h kg-1) and power density (750.2 W kg-1) at a current density of 1 A g-1, along with very good cycling stability of 91.4% even after 5000 GCD cycles. The SSC device was able to power up several LED lights and even operated a DC brushless fan for a significant amount of time. To the best of our knowledge, the assembled SSC device exhibits the highest energy density among the MOF composite-based SSCs reported so far.

9.
Genet Med ; 26(7): 101143, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38641995

RESUMO

PURPOSE: Neurodevelopmental disorders exhibit clinical and genetic heterogeneity, ergo manifest dysfunction in components of diverse cellular pathways; the precise pathomechanism for the majority remains elusive. METHODS: We studied 5 affected individuals from 3 unrelated families manifesting global developmental delay, postnatal microcephaly, and hypotonia. We used exome sequencing and prioritized variants that were subsequently characterized using immunofluorescence, immunoblotting, pulldown assays, and RNA sequencing. RESULTS: We identified biallelic variants in ZFTRAF1, encoding a protein of yet unknown function. Four affected individuals from 2 unrelated families segregated 2 homozygous frameshift variants in ZFTRAF1, whereas, in the third family, an intronic splice site variant was detected. We investigated ZFTRAF1 at the cellular level and signified it as a nucleocytoplasmic protein in different human cell lines. ZFTRAF1 was completely absent in the fibroblasts of 2 affected individuals. We also identified 110 interacting proteins enriched in mRNA processing and autophagy-related pathways. Based on profiling of autophagy markers, patient-derived fibroblasts show irregularities in the protein degradation process. CONCLUSION: Thus, our findings suggest that biallelic variants of ZFTRAF1 cause a severe neurodevelopmental disorder.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38528801

RESUMO

OBJECTIVES: Studies have investigated miR-125a for its predictable role in recurrent pregnancy loss (RPL) cases to regulate many biological events required for the maintenance of pregnancy by regulating its confirmed target genes LIFR, ERBB2 and STAT3. METHODS: The present study included 40 cases of women with at least two RPLs in ≤20 weeks of gestation against 40 healthy multiparous women without a previous history of abortion. Expression analysis of ERBB2, LIFR, STAT3 and miR-125a was conducted by quantitative real-time PCR (qPCR). RESULTS: The expression of miR-125a was significantly lower in the plasma of RPL cases (P = 0.0001) and showed a significantly increased mean expression level in product of conception (2.56-fold, P < 0.0001). Among the target gene of miR-125a, ERBB2 and STAT3 gene expression level was significantly increased (2.58-fold, P = 0.04; 1.87-fold, P = 0.025), respectively in RPL cases while the LIFR gene revealed comparable expression (P = 0.64). Furthermore, expression analysis of ERBB2 gene with respect to its regulatory miR-125a cases depicted a significant association (P = 0.0005). Kaplan-Meier survival analysis revealed cases with low miR-125a expression had significantly shorter time to miscarriages, (log-rank P = 0.02). Also, decreased expression of miR-125a significantly conferred >2-fold increased risk for RPL (HR = 2.34: P < 0.05). CONCLUSION: The overall conclusion of the study was that altered miR-125a expression may cause deregulation in target genes LIFR, ERBB2 and STAT3 resulting in adverse consequence in the outcome of pregnancy.

11.
Anaesth Rep ; 12(1): e12281, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464955

RESUMO

The presentation of acute and rapidly deteriorating airway pathology can be a highly challenging situation for any hospital team. Cricoid chondromas are a challenging and potentially unfamiliar airway pathology requiring the combined expertise of anaesthetists, ear, nose and throat surgeons and a wider peri-operative team familiar with managing airway emergencies. Airway lesions which cause rigid and fixed stenosis require careful management and present additional challenges compared to soft tissue lesions. An important consideration in fixed airway stenosis is the external diameter of tracheal tubes compared to the diameter of the airway at its narrowest point. These are challenging cases to manage and a multi-disciplinary approach to the safe management of unfamiliar and critical airway pathology should be adopted.

13.
J Neurosurg ; : 1-6, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457788

RESUMO

OBJECTIVE: A growing body of literature suggests that preoperative opioid exposure is an independent predictor of poor outcomes in surgical patients. No outcomes data exist on preoperative opioid use and craniotomies/craniectomies. The objective of this study was to determine the impact of preoperative opioid use on 90-day adverse events after craniotomy or craniectomy. METHODS: A single-center retrospective cohort study of 2445 patients undergoing a craniotomy/craniectomy between January 1, 2013, and October 1, 2018, was conducted. Baseline demographics, pre- and postoperative opioid use (morphine milligram equivalents [MMEs]), and surgical metrics were recorded. Patients were categorized based on whether they took prescription opioids preoperatively, defined as within 1 month of surgery, or were opioid naive. The outcomes were mortality and adverse events 90 days after craniotomy/craniectomy. RESULTS: Overall, 26.6% of patients composed the preoperative opioid group. The median daily MME intake among this group was 34.6 (IQR 14.1-90) MMEs. Lower employment rates (p < 0.001), uninsured status (p = 0.016), and intravenous drug use (p = 0.006) were associated with preoperative opioid use. Preoperative opioid use was associated with increased venous thromboembolism (p = 0.001), acute kidney injury (p = 0.002), acute respiratory failure (p < 0.001), myocardial infarction (p = 0.002), delirium (p < 0.001), and infection (p < 0.001). Preoperative opioid use was an independent predictor of overall 90-day adverse events (OR 1.643, 95% CI 1.289-2.095; p < 0.001) and 90-day mortality (OR 1.690, 95% CI 1.254-2.277; p < 0.001). CONCLUSIONS: Preoperative opioid use was independently associated with 90-day postoperative adverse events and mortality. Opioid use increases vulnerability in craniotomy/craniectomy patients and necessitates close monitoring to improve outcomes.

14.
Environ Geochem Health ; 46(2): 65, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321197

RESUMO

Rice-based integrated farming system improves the productivity and profitability by recycling resources efficiently. In the sub-humid tropics, rice production without sufficient nutrient replenishment often leads to soil health and fertility degradation. There has been very limited research on soil health and fertility after adopting a multi-enterprising rice-based integrated farming system (IFS), notably in the rice-fish-livestock and agroforestry system, when compared to a conventional farming system (CS). Therefore, the present study analyzed the dynamics of soil properties, soil bacterial community structure and their possible interaction mechanisms, as well as their effect on regulating soil quality and production in IFS, IFSw (water stagnant area of IFS) and CS. The results indicated that soil nutrient dynamics, bacterial diversity indices (Shannon index, Simpson index, Chao 1, ACE and Fisher index) and system productivity were higher in IFSw and IFS compared to CS. Moreover, relative operational taxonomic units of dominant bacterial genera (Chloroflexi, Acidobacteria, Verrucomicrobia, Planctomycetes, Cyanobacteria, Crenarchaeota and Gemmatimonadetes) were also higher in IFSw and IFS compared to CS. Mean soil quality index (SQI) was highest in IFSw (0.780 ± 0.201) followed by IFS (0.770 ± 0.080) and CS (0.595 ± 0.244). Moreover, rice equivalent yields (REY) and rice yields were well correlated with the higher levels of soil biological indices (SQIBiol) in IFS. Overall, our results revealed that rice-based IFS improved the soil health and fertility and ensuing crop productivity through positive interaction with soil bacterial communities and nutrient stoichiometry leading to agroecosystem sustainability.


Assuntos
Oryza , Solo , Solo/química , Clima Tropical , Agricultura/métodos , Bactérias , Microbiologia do Solo
15.
Opt Express ; 32(3): 4376-4386, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297640

RESUMO

Numerical analysis of Dyakonov waves generation has been carried out at uniaxial chiral-plasma planar interface. The extended electromagnetic wave theory is utilized, and an impedance boundary conditions approach is employed to obtain characteristics equation. Effective mode index and attenuation under the different values of collisional frequency, plasma frequency and chirality in the THz frequency range for three cases for uniaxial chiral media are discussed. These results can be used in the field of photonics and integrated optics to fabricate nanophotonic devices in the THz frequency range.

16.
Eur Rev Med Pharmacol Sci ; 28(3): 1194-1201, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38375724

RESUMO

OBJECTIVE: This study aimed to investigate the association between serum galanin (GAL) and neuron-specific enolase (NSE) levels in children with convulsive status epilepticus (CSE) and their relationship with abnormal electroencephalogram (EEG) patterns. Additionally, the study assessed the effectiveness of a combination therapy involving midazolam, diazepam, and phenobarbital in treating CSE. PATIENTS AND METHODS: The research involved 100 children diagnosed with CSE and included a control group of 50 healthy children. Serum GAL and NSE levels were measured, and EEGs were analyzed for abnormalities in the CSE group. Comparisons were made between the healthy control group and the CSE group, particularly within the first 24 hours after persistent seizures. The severity of EEG abnormalities was correlated with GAL and NSE levels. The treatment consisted of an observation group that received the triple therapy of midazolam, diazepam, and phenobarbital, while a control group received diazepam and phenobarbital. Clinical efficacy, symptom improvement, Status Epilepticus Severity Score (STESS), and adverse reactions were evaluated. RESULTS: The results indicated elevated levels of GAL and NSE in the CSE group, with higher levels noted within 24 hours after persistent seizures. Furthermore, a positive correlation was observed between the severity of EEG abnormalities and GAL and NSE levels. The group receiving the triple therapy demonstrated superior efficacy, faster resolution of seizures and fever, reduced STESS scores, and fewer adverse reactions than the control group. In conclusion, this study highlights the positive correlation between serum GAL and NSE levels and the severity of EEG abnormalities in pediatric CSE. The triple therapy approach is effective in treating CSE, leading to improved clinical symptoms, reduced brain damage, and enhanced safety. CONCLUSIONS: The study concludes that serum GAL and NSE levels in children with convulsive status epilepticus are positively correlated with the degree of EEG abnormalities. The combination therapy involving midazolam, diazepam, and phenobarbital is effective in treating children with convulsive status epilepticus, significantly improving clinical symptoms, reducing brain damage, and ensuring safety.


Assuntos
Lesões Encefálicas , Estado Epiléptico , Criança , Humanos , Midazolam/uso terapêutico , Galanina , Estado Epiléptico/diagnóstico , Estado Epiléptico/tratamento farmacológico , Convulsões/tratamento farmacológico , Diazepam/uso terapêutico , Fenobarbital/uso terapêutico , Eletroencefalografia , Lesões Encefálicas/tratamento farmacológico , Fosfopiruvato Hidratase , Anticonvulsivantes/uso terapêutico
17.
Interv Neuroradiol ; : 15910199241227262, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38258391

RESUMO

BACKGROUND: The modified Rankin Scale (mRS) is a clinician-reported scale that measures the degree of disability in patients who suffered a stroke. Patients' perception of a meaningful recovery from severe stroke, expected value of a stroke intervention, and the effect of disparities are largely unknown. METHODS: We conducted a survey of patients, their family members, and accompanying visitors to understand their personal preferences and expectations for acute strokes potentially eligible for acute endovascular intervention using a hypothetical scenario of a severe stroke in a standardized questionnaire. RESULTS: Of 164 survey respondents, 65 (39.6%) were the patient involved, 93 (56.7%) were a family member, and six (3.7%) were accompanied visitors (friends, other). Minimally acceptable disability after a stroke intervention was considered as mRS 2 by 42 respondents (25.6%), as mRS 3 by 79 (48.2%), and as mRS 4 by 43 (26.2%) respondents. Race was associated with different views on this question (p < 0.001; Hispanic and Black patients being more likely to accept disability than Caucasian and Asian patients), while sex (p = 0.333) and age (p = 0.560) were not. Sixty-three respondents (38.4%) viewed minimally acceptable probability of improvement with an intervention as over 50%, 57 (34.8%) as 10-50%, and 44 (26.8%) as less than 10%. CONCLUSIONS: A wide range of acceptable outcomes were reported regardless of gender or age. However, race was associated with different acceptable outcome. This is an important finding to demonstrate because of the persistent racial and ethnic disparities in the utilization of endovascular therapy for acute stroke in the United States.

18.
Org Biomol Chem ; 22(4): 753-758, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38165787

RESUMO

Regioselective arylation of carbazoles is reported using dual palladium-photoredox catalysis. Controlled monoarylation and diarylation of symmetrical and unsymmetrical carbazoles were achieved under mild reaction conditions with a broad substrate scope and functional group tolerance. Steric and electronic control the regioselectivity of the arylation of unsymmetrical carbazoles. Late-stage functionalization of a caprofen drug derivative and large-scale synthesis of mono- and di-arylated carbazoles were demonstrated to showcase the synthetic versatility of the method. Finally, we also showcased the synthesis of hyellazole analogues (a marine alkaloid) in a short route using our strategy.

19.
J Biomol Struct Dyn ; 42(5): 2698-2713, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37154523

RESUMO

Lipid peroxidation (LPO) is a biological process that frequently occurs under physiological conditions. Undue oxidative stress increases the level of LPO; which may further contribute to the development of cancer. 4-Hydroxy-2-nonenal (HNE), one of the principal by-products of LPO, is present in high concentrations in oxidatively stressed cells. HNE rapidly reacts with various biological components, including DNA and proteins; however, the extent of protein degradation by lipid electrophiles is not well understood. The influence of HNE on protein structures will likely have a considerable therapeutic value. This research elucidates the potential of HNE, one of the most researched phospholipid peroxidation products, in modifying low-density lipoprotein (LDL). In this study, we tracked the structural alterations in LDL by HNE using various physicochemical techniques. To comprehend the stability, binding mechanism and conformational dynamics of the HNE-LDL complex, computational investigations were carried out. LDL was altered in vitro by HNE, and the secondary and tertiary structural alterations were examined using spectroscopic methods, such as UV-visible, fluorescence, circular dichroism and fourier transform infrared spectroscopy. Carbonyl content, thiobarbituric acid-reactive-substance (TBARS) and nitroblue tetrazolium (NBT) reduction assays were used to examine changes in the oxidation status of LDL. Thioflavin T (ThT), 1-anilinonaphthalene-8-sulfonic (ANS) binding assay and electron microscopy were used to investigate aggregates formation. According to our research, LDL modified by HNE results in changes in structural dynamics, oxidative stress and the formation of LDL aggregates. The current investigation must characterize HNE's interactions with LDL and comprehend how it can change their physiological or pathological functions.Communicated by Ramaswamy H. Sarma.


Assuntos
Aldeídos , Lipoproteínas LDL , Humanos , Lipoproteínas LDL/química , Lipoproteínas LDL/metabolismo , Aldeídos/metabolismo , Aldeídos/farmacologia , Oxirredução , Peroxidação de Lipídeos
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