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Background and Aims: The association of immunotherapy in combination with radiation therapy (RT) or chemoradiation with the overall survival (OS) of patients diagnosed with stage IV esophageal cancer (EC) is unknown. The aim of the current study is to explore the association of immunotherapy with OS in patients with advanced stage EC who received chemotherapy, RT, or chemoradiation. Methods: We conducted a cohort study using the National Cancer Database and included patients diagnosed between 2013 and 2020 with stage IV esophageal adenocarcinoma or squamous cell carcinoma. The association of immunotherapy with OS was assessed with Cox proportional hazards regression, adjusted for age at diagnosis, race, sex, stage, histology, Charlson score, education, income, insurance, hospital type, place of living, region, distance to facility, year of diagnosis, and treatment modality. Results: Of 18,260 patients, 2946 (17%) received immunotherapy. In the multivariable COX analysis, patients who received immunotherapy had significantly improved OS compared with no immunotherapy (hazard ratio [HR]: 0.71; 95% confidence interval [CI]: 0.67-0.75; P < .001). Chemotherapy plus immunotherapy was associated with improved OS compared to chemotherapy alone (HR: 0.69; 95% CI: 0.64-0.75; P < .001). RT plus immunotherapy was associated with improved OS compared to RT alone (HR: 0.60; 95% CI: 0.46-0.78; P < .001). Treatment with chemoradiation plus immunotherapy was associated with significantly improved OS compared with chemoradiation alone (HR 0.78; 95% CI: 0.71-0.86; P < .001). Conclusion: The addition of immunotherapy to chemotherapy, RT, and chemoradiation was associated with improved OS compared with chemotherapy alone, RT alone, or chemoradiation alone in patients with stage IV EC.
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Sepsis arises from an uncontrolled inflammatory response triggered by infection or stress, accompanied by alteration in cellular energy metabolism, and a strong correlation exists between these factors. Alpha-ketoglutarate (α-KG), an intermediate product of the TCA cycle, has the potential to modulate the inflammatory response and is considered a crucial link between energy metabolism and inflammation. The scavenger receptor (SR-A5), a significant pattern recognition receptor, assumes a vital function in anti-inflammatory reactions. In the current investigation, we have successfully illustrated the ability of α-KG to mitigate inflammatory factors in the serum of septic mice and ameliorate tissue damage. Additionally, α-KG has been shown to modulate metabolic reprogramming and macrophage polarization. Moreover, our findings indicate that the regulatory influence of α-KG on sepsis is mediated through SR-A5. We also elucidated the mechanism by which α-KG regulates SR-A5 expression and found that α-KG reduced the N6-methyladenosine level of macrophages by up-regulating the m6A demethylase ALKBH5. α-KG plays a crucial role in inhibiting inflammation by regulating SR-A5 expression through m6A demethylation during sepsis. The outcomes of this research provide valuable insights into the relationship between energy metabolism and inflammation regulation, as well as the underlying molecular regulatory mechanism.
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Introduction: A mini-laparotomy for colorectal cancer (CRC) has been reported to shorten postoperative ileus (POI) and hospital stay. Interleukin-6 (IL-6) plays a role in intestinal tissue inflammation, leading to POI. This study investigated the effects of abdominal wounds and IL-6 levels on POI in patients having CRC surgery. Materials and methods: Forty-three patients with CRC underwent bowel resection. Serum samples were collected preoperatively and at 2, 24, and 48â h after surgery for cytokine quantification by ELISA. Clinical data, including time from surgery to first passage of flatus and postoperative hospital stay, demographic and pathological data, and routine blood tests, were compared statistically with abdominal wound length and the postoperative increments of cytokines (designated as Δ). Results: The length of the abdominal wound showed a significant correlation with clinical variables (length of operation time, time of first flatus passage, and length of postoperative hospital stay) and cytokine variables (IL-6(Δ2â h), IL-8(Δ2â h) and IL-10(Δ2â h). Linear regression analysis showed that the abdominal wound length significantly influenced the operation time, time of first flatus passage, and length of postoperative hospital stay (p < 0.001). The length of the abdominal wound showed a significant influence on the IL-6(Δ2â h) and IL-8(Δ2â h) (p < 0.001, respectively) but no influence on IL-10(Δ2â h). IL-6(Δ2â h), but not IL-8(Δ2â h), significantly influenced the time to first flatus passage and length of hospital stay (p = 0.007, p = 0.006, respectively). The mini-laparotomy approach (wound length <7â cm) led to significantly shortened operation time, time of first flatus passage, length of postoperative stay (pâ =â 0.004, p = 0.003, p = 0.006, respectively) as well as reduced postoperative increment of IL-6(Δ2â h) (p = 0.015). The mini-laparotomy for anterior resection surgery significantly influenced operation time, time of first passage of flatus, length of postoperative stay, and IL-6(Δ2â h). Conclusion: Our study is the first to report the complex interaction among the length of the abdominal wound, IL-6 serum level, recovery of the first passage of flatus, and postoperative hospital stay. These results suggest that smaller abdominal wounds and smaller postoperative IL-6 increments were associated with faster recovery of flatus passage and shorter hospital stays.
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OBJECTIVE: Cerebral arteriovenous malformation during pregnancy is rare but lethal disease that usually present with new-onset seizures and headaches mimicking eclampsia. We report a rare case of cerebral arteriovenous malformation with abrupt seizures in the third trimester. CASE REPORT: A 28-year-old primipara was brought to our emergency department at 32 6/7 weeks of gestation with new-onset acute seizures and hypertension. Owing to neurological deterioration, the patient underwent emergency cesarean delivery. However, 24 h after cesarean delivery and eclampsia treatment, the seizures worsened. Computed tomography and magnetic resonance imaging showed unruptured arteriovenous malformation of the right frontal lobe. Subsequently, intraarterial embolization was performed. The patient was discharged 5 days after surgery without neurological sequelae or obstetric complications. CONCLUSION: This case report highlights the differential diagnoses of sudden new-onset seizures in late pregnancy for obstetricians and emergency medicine physicians. Lethal cerebral diseases, apart from eclampsia, should be considered during pregnancy.
Subject(s)
Cesarean Section , Eclampsia , Headache , Intracranial Arteriovenous Malformations , Seizures , Humans , Female , Pregnancy , Eclampsia/diagnosis , Adult , Seizures/etiology , Seizures/diagnosis , Headache/etiology , Diagnosis, Differential , Intracranial Arteriovenous Malformations/complications , Intracranial Arteriovenous Malformations/diagnosis , Intracranial Arteriovenous Malformations/therapy , Magnetic Resonance Imaging , Embolization, Therapeutic , Pregnancy Complications, Cardiovascular/diagnosis , Pregnancy Complications, Cardiovascular/therapy , Tomography, X-Ray Computed , Pregnancy Trimester, ThirdABSTRACT
This study is the first to investigate the effects of external resistance and electrolyte concentration on the performance of a bioelectro-Fenton (BEF) system, involving measurements of power density, H2O2 generation, and bisphenol A (BPA) removal efficiency. With optimized operating conditions (external resistance of 1.12 kΩ and cathodic NaCl concentration of 1,657 mg/L), the BEF system achieved a maximum power density of 38.59 mW/m2, which is about 3.5 times higher than with 1 kΩ external resistance and no NaCl. This system featured a 71.7 % reduction in total internal resistance. The optimized BEF also accelerated the oxygen reduction reaction rate, increasing H2O2 generation by 4.4 times compared to the unoptimized system. Moreover, it exhibited superior BPA degradation performance, removing over 99 % of BPA within 14 hs, representing a 1.1 to 3.3-fold improvement over the unoptimized BEF. By the fifth cycle (70 h), the optimized BEF still removed 70 % of BPA. Optimizing the operating conditions significantly increased the abundance of electrochemically active bacteria (Pseudomonadaceae) from 2.2 % to 20 %, facilitating rapid acclimation. The study demonstrates the strong potential of an optimized BEF system for removing persistent pollutants.
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Background and Objectives: This paper evaluates the efficacy and safety of ureteral access sheath (UAS) utilization in retrograde intrarenal surgery (RIRS). Materials and Methods: We searched PubMed, Embase, and the Cochrane Library up to 30 August 2023. The inclusion criteria comprised English-language original studies on RIRS with or without UAS in humans. The primary outcome was SFR, while the secondary outcomes included intraoperative and postoperative complications, the lengths of the operation and the hospitalization period, and the duration of the fluoroscopy. Subgroup analyses and a sensitivity analysis were performed. Publication bias was assessed using funnel plots and Egger's regression tests. Dichotomous variables were analyzed using odds ratios (ORs) with 95% confidence intervals (CIs), while mean differences (MDs) were employed for continuous variables. Results: We included 22 studies in our analysis. These spanned 2001 to 2023, involving 12,993 patients and 13,293 procedures. No significant difference in SFR was observed between the UAS and non-UAS groups (OR = 0.90, 95% CI 0.63-1.30, p = 0.59). Intraoperative (OR = 1.13, 95% CI 0.75-1.69, p = 0.5) and postoperative complications (OR = 1.29, 95% CI 0.89-1.87, p = 0.18) did not significantly differ between the groups. UAS usage increased operation times (MD = 8.30, 95% CI 2.51-14.10, p = 0.005) and fluoroscopy times (MD = 5.73, 95% CI 4.55-6.90, p < 0.001). No publication bias was detected for any outcome. Conclusions: In RIRS, UAS usage did not significantly affect SFR, complications, or hospitalization time. However, it increased operation time and fluoroscopy time. Routine UAS usage is not supported, and decisions should be patient-specific. Further studies with larger sample sizes and standardized assessments are needed to refine UAS utilization in RIRS.
Subject(s)
Ureter , Humans , Ureter/surgery , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Operative Time , Kidney/surgery , Urologic Surgical Procedures/methods , Urologic Surgical Procedures/statistics & numerical data , Urologic Surgical Procedures/adverse effects , Length of Stay/statistics & numerical dataABSTRACT
Metabolic-associated fatty liver disease (MAFLD) is predominantly associated with metabolic disturbances representing aberrant liver function and increased uric acid (UA) levels. Growing evidences have suggested a close relationship between metabolic disturbances and the gut microbiota. A placebo-controlled, double-blinded, randomized clinical trial was therefore conducted to explore the impacts of daily supplements with various combinations of the probiotics, Lactobacillus fermentum TSF331, Lactobacillus reuteri TSR332, and Lactobacillus plantarum TSP05 with a focus on liver function and serum UA levels. Test subjects with abnormal levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and UA were recruited and randomly allocated into six groups. Eighty-two participants successfully completed the 60-day intervention without any dropouts or occurrence of adverse events. The serum AST, ALT, and UA levels were significantly reduced in all treatment groups (P < 0.05). The fecal microbiota analysis revealed the intervention led to an increase in the population of commensal bacteria and a decrease in pathobiont bacteria, especially Bilophila wadsworthia. The in vitro study indicated the probiotic treatments reduced lipid accumulation and inflammatory factor expressions in HepG2 cells, and also promoted UA excretion in Caco-2 cells. The supplementation of multi-strain probiotics (TSF331, TSR332, and TSP05) together can improve liver function and UA management and may have good potential in treating asymptomatic MAFLD. Trial registration. The trial was registered in the US Library of Medicine (clinicaltrials.gov) with the number NCT06183801 on December 28, 2023.
Subject(s)
Lactobacillus plantarum , Limosilactobacillus fermentum , Limosilactobacillus reuteri , Probiotics , Uric Acid , Humans , Probiotics/administration & dosage , Lactobacillus plantarum/physiology , Male , Uric Acid/blood , Uric Acid/metabolism , Female , Pilot Projects , Middle Aged , Double-Blind Method , Liver/metabolism , Adult , Gastrointestinal Microbiome/drug effects , Hep G2 Cells , Caco-2 Cells , Aspartate Aminotransferases/blood , Feces/microbiology , Alanine Transaminase/bloodABSTRACT
Transmembrane-4 L-six family member-1 (TM4SF1) is an atypical tetraspanin that is highly and selectively expressed in proliferating endothelial cells and plays an essential role in blood vessel development. TM4SF1 forms clusters on the cell surface called TMED (TM4SF1-enriched microdomains) and recruits other proteins that internalize along with TM4SF1 via microtubules to intracellular locations including the nucleus. We report here that tumor growth and wound healing are inhibited in Tm4sf1-heterozygous mice. Investigating the mechanisms of TM4SF1 activity, we show that 12 out of 18 signaling molecules examined are recruited to TMED on the surface of cultured human umbilical vein endothelial cells (HUVEC) and internalize along with TMED; notable among them are PLCγ and HDAC6. When TM4SF1 is knocked down in HUVEC, microtubules are heavily acetylated despite normal levels of HDAC6 protein, and, despite normal levels of VEGFR2, are unable to proliferate. Together, our studies indicate that pathological angiogenesis is inhibited when levels of TM4SF1 are reduced as in Tm4sf1-heterozygous mice; a likely mechanism is that TM4SF1 regulates the intracellular distribution of signaling molecules necessary for endothelial cell proliferation and migration.
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BACKGROUND: Volatile organic compounds (VOC) are major indoor air pollutants. Previous studies reported an association between VOC exposure and allergic diseases. Here, we aimed to explore the relationship between VOC exposure and atopic dermatitis (AD) in adults. METHODS: We prospectively enrolled 31 adult AD patients and 11 healthy subjects as controls. Urine metabolite levels of VOCs, including 1.3-butadiene, acrylamide, benzene, toluene, and xylene, were all determined with liquid chromatography-mass spectrometry. The relationship between AD and log-transformed urine levels of VOC metabolites were examined using a multivariate linear regression model adjusted for age and sex. We also treated mouse bone marrow-derived cells (BMMCs) with 1,3-butadiene and toluene and measured the release of ß-hexosaminidase. RESULTS: Our results demonstrated that creatinine-corrected urine levels of N-Acetyl-S- (3,4-dihydroxybutyl)-L-cysteine (DHBMA), N-Acetyl-S-(2-carbamoyl-2-hydroxyethyl)-L-cysteine (GAMA), and N-Acetyl-S-(benzyl)-L-cysteine (BMA) were all elevated in AD patients compared with controls. In a multivariate linear regression model, creatinine-corrected urine levels of BMA (a toluene metabolite) and DHBMA (a 1,3-butadiene metabolite) appeared elevated in AD patients, although statistical significance was not reached after correction for multiple comparisons. In addition, 1,3-butadiene and toluene could stimulate BMMCs to degranulate as much as compound 48/80. CONCLUSIONS: Some VOCs, such as 1,3-butadiene and toluene, might be associated with AD pathogenesis in adults.
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STATEMENT OF PROBLEM: The complete arch implant-supported treatment concept with 2 angled implants has been widely used for the prosthetic rehabilitation of edentulous patients. While mechanical analysis plays a pivotal role in minimizing suboptimal outcomes or premature failure, it is notably time-consuming. Consequently, clinical treatment planning relies heavily on dentists' subjective judgment and an optimization process is needed. PURPOSE: The purpose of this study was to develop an optimization process for providing immediate recommendations to support decision-making in configuring complete arch implant-supported prostheses. MATERIAL AND METHODS: This research was carried out in 2 phases. The first consisted of collecting a dataset from a total of 2800 finite element simulations by randomly configuring 10 implant design variables with 4 types of mandibles. The dataset was used to train an artificial neural network to predict the biomechanical performance of a given complete arch implant-supported prosthesis design configuration. In the second phase, the artificial neural network was used as the objective function predictor in a particle swarm optimization process to enable immediate recommendations for the implant placement. The optimization process was evaluated for accuracy, computing performance, and adaptability for unseen mandibles. RESULTS: Within the specified design space, the optimization process was able to find an optimal design based on an imported mandible model in 30 seconds. The optimized designs were found to improve peri-implant stress by 11.08 ±6.43%. When verified through finite element analysis, the prediction error was found to be 10.4 ±8.1%. Furthermore, the prediction of the optimal design was highly accurate when tested on 2 unseen mandibles, yielding an error of less than 1.7%. CONCLUSIONS: The suggested approach can quickly provide an optimal implant configuration for each individual and effectively reduce the average peri-implant stress in the mandible.
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Baloxavir acid (BXA) is a pan-influenza antiviral that targets the cap-dependent endonuclease of the polymerase acidic (PA) protein required for viral mRNA synthesis. To gain a comprehensive understanding on the molecular changes associated with reduced susceptibility to BXA and their fitness profile, we performed a deep mutational scanning at the PA endonuclease domain of an A (H1N1)pdm09 virus. The recombinant virus libraries were serially passaged in vitro under increasing concentrations of BXA followed by next-generation sequencing to monitor PA amino acid substitutions with increased detection frequencies. Enriched PA amino acid changes were each introduced into a recombinant A (H1N1)pdm09 virus to validate their effect on BXA susceptibility and viral replication fitness in vitro. The I38 T/M substitutions known to confer reduced susceptibility to BXA were invariably detected from recombinant virus libraries within 5 serial passages. In addition, we identified a novel L106R substitution that emerged in the third passage and conferred greater than 10-fold reduced susceptibility to BXA. PA-L106 is highly conserved among seasonal influenza A and B viruses. Compared to the wild-type virus, the L106R substitution resulted in reduced polymerase activity and a minor reduction of the peak viral load, suggesting the amino acid change may result in moderate fitness loss. Our results support the use of deep mutational scanning as a practical tool to elucidate genotype-phenotype relationships, including mapping amino acid substitutions with reduced susceptibility to antivirals.
Subject(s)
Amino Acid Substitution , Antiviral Agents , Dibenzothiepins , Drug Resistance, Viral , Influenza A Virus, H1N1 Subtype , Morpholines , Pyridones , Triazines , Viral Proteins , Virus Replication , Dibenzothiepins/pharmacology , Drug Resistance, Viral/genetics , Antiviral Agents/pharmacology , Influenza A Virus, H1N1 Subtype/drug effects , Influenza A Virus, H1N1 Subtype/genetics , Triazines/pharmacology , Virus Replication/drug effects , Pyridones/pharmacology , Humans , Morpholines/pharmacology , Viral Proteins/genetics , Animals , Thiepins/pharmacology , RNA-Dependent RNA Polymerase/genetics , High-Throughput Nucleotide Sequencing , Dogs , Madin Darby Canine Kidney Cells , Influenza, Human/virology , Influenza, Human/drug therapy , Oxazines/pharmacologyABSTRACT
Receptor tyrosine kinases (RTKs) control stem cell maintenance vs. differentiation decisions. Casitas B-lineage lymphoma (CBL) family ubiquitin ligases are negative regulators of RTKs, but their stem cell regulatory roles remain unclear. Here, we show that Lgr5+ intestinal stem cell (ISC)-specific inducible Cbl-knockout (KO) on a Cblb null mouse background (iDKO) induced rapid loss of the Lgr5 Hi ISCs with transient expansion of the Lgr5 Lo transit-amplifying population. LacZ-based lineage tracing revealed increased ISC commitment toward enterocyte and goblet cell fate at the expense of Paneth cells. Functionally, Cbl/Cblb iDKO impaired the recovery from radiation-induced intestinal epithelial injury. In vitro, Cbl/Cblb iDKO led to inability to maintain intestinal organoids. Single-cell RNA sequencing in organoids identified Akt-mTOR (mammalian target of rapamycin) pathway hyperactivation upon iDKO, and pharmacological Akt-mTOR axis inhibition rescued the iDKO defects. Our results demonstrate a requirement for Cbl/Cblb in the maintenance of ISCs by fine-tuning the Akt-mTOR axis to balance stem cell maintenance vs. commitment to differentiation.
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Staphylococcus aureus (S. aureus) is a major global health concern, causing various infections and presenting challenges due to antibiotic resistance. In particular, methicillin-resistant S. aureus, vancomycin-intermediate S. aureus (VISA), and vancomycin-resistant S. aureus pose significant obstacles in treating S. aureus infections. Therefore, the critical need for novel drugs to counter these resistant forms is pressing. Two-component systems (TCSs), integral to bacterial regulation, offer promising targets for disruption. In this study, a comprehensive approach, involving pharmacophore-based inhibitor screening, along with biochemical and biophysical analyses were conducted to identify, characterize, and validate potential inhibitors targeting the response regulator VraRC of S. aureus. The constructed pharmacophore model, Phar-VRPR-N3, demonstrated effectiveness in identifying a potent inhibitor, TST1N-224 (IC50 = 60.2 ± 4.0 µM), against the formation of the VraRC-DNA complex. Notably, TST1N-224 exhibited strong binding to VraRC (KD = 23.4 ± 1.2 µM) using a fast-on-fast-off binding mechanism. Additionally, NMR-based molecular modeling revealed that TST1N-224 predominantly interacts with the α9- and α10-helixes of the DNA-binding domain of VraR, where the interactive and functionally essential residues (N165, K180, S184, and R195) act as hotspots for structure-based inhibitor optimization. Furthermore, TST1N-224 evidently enhanced the susceptibility of VISA to both vancomycin and methicillin. Importantly, TST1N-224 distinguished by 1,2,5,6-tetrathiocane with the 3 and 8 positions modified with ethanesulfonates holds significant potential as a lead compound for the development of new antimicrobial agents.
Subject(s)
Anti-Bacterial Agents , Bacterial Proteins , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Bacterial Proteins/antagonists & inhibitors , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Staphylococcus aureus/drug effects , Drug Discovery , Microbial Sensitivity Tests , Drug Evaluation, Preclinical , Molecular Docking Simulation , Methicillin-Resistant Staphylococcus aureus/drug effects , Models, Molecular , PharmacophoreABSTRACT
In oncology, melanoma is a serious concern, often arising from DNA changes caused mainly by ultraviolet radiation. This cancer is known for its aggressive growth, highlighting the necessity of early detection. Our research introduces a novel deep learning framework for melanoma classification, trained and validated using the extensive SIIM-ISIC Melanoma Classification Challenge-ISIC-2020 dataset. The framework features three dilated convolution layers that extract critical feature vectors for classification. A key aspect of our model is incorporating the Off-policy Proximal Policy Optimization (Off-policy PPO) algorithm, which effectively handles data imbalance in the training set by rewarding the accurate classification of underrepresented samples. In this framework, the model is visualized as an agent making a series of decisions, where each sample represents a distinct state. Additionally, a Generative Adversarial Network (GAN) augments training data to improve generalizability, paired with a new regularization technique to stabilize GAN training and prevent mode collapse. The model achieved an F-measure of 91.836% and a geometric mean of 91.920%, surpassing existing models and demonstrating the model's practical utility in clinical environments. These results demonstrate its potential in enhancing early melanoma detection and informing more accurate treatment approaches, significantly advancing in combating this aggressive cancer.
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BACKGROUND: Changing the course duration or timing of subjects in learning pathways would influence medical students' learning outcomes. Curriculum designers need to consider the strategy of reducing cognitive load and evaluate it continuously. Our institution underwent gradual curricular changes characterized by reducing cognitive load since 2000. Therefore, we wanted to explore the impact of this strategy on our previous cohorts. METHODS: This cohort study explored learning pathways across academic years of more than a decade since 2000. Eight hundred eighty-two medical students between 2006 and 2012 were included eventually. Learning outcomes included an average and individual scores of subjects in different stages. Core subjects were identified as those where changes in duration or timing would influence learning outcomes and constitute different learning pathways. We examined whether the promising learning pathway defined as the pathway with the most features of reducing cognitive load has higher learning outcomes than other learning pathways in the exploring dataset. The relationship between features and learning outcomes was validated by learning pathways selected in the remaining dataset. RESULTS: We found nine core subjects, constituting four different learning pathways. Two features of extended course duration and increased proximity between core subjects of basic science and clinical medicine were identified in the promising learning pathway 2012, which also had the highest learning outcomes. Other pathways had some of the features, and pathway 2006 without such features had the lowest learning outcomes. The relationship between higher learning outcomes and cognitive load-reducing features was validated by comparing learning outcomes in two pathways with and without similar features of the promising learning pathway. CONCLUSION: An approach to finding a promising learning pathway facilitating students' learning outcomes was validated. Curricular designers may implement similar design to explore the promising learning pathway while considering potential confounding factors, including students, medical educators, and learning design of the course.
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Cognition , Learning , Humans , Cohort Studies , Students, Medical/psychology , Curriculum , Female , MaleABSTRACT
N-Acetylnorloline synthase (LolO) is one of several iron(II)- and 2-oxoglutarate-dependent (Fe/2OG) oxygenases that catalyze sequential reactions of different types in the biosynthesis of valuable natural products. LolO hydroxylates C2 of 1-exo-acetamidopyrrolizidine before coupling the C2-bonded oxygen to C7 to form the tricyclic loline core. Each reaction requires cleavage of a C-H bond by an oxoiron(IV) (ferryl) intermediate; however, different carbons are targeted, and the carbon radicals have different fates. Prior studies indicated that the substrate-cofactor disposition (SCD) controls the site of H· abstraction and can affect the reaction outcome. These indications led us to determine whether a change in SCD from the first to the second LolO reaction might contribute to the observed reactivity switch. Whereas the single ferryl complex in the C2 hydroxylation reaction was previously shown to have typical Mössbauer parameters, one of two ferryl complexes to accumulate during the oxacyclization reaction has the highest isomer shift seen to date for such a complex and abstracts H· from C7 â¼ 20 times faster than does the first ferryl complex in its previously reported off-pathway hydroxylation of C7. The detectable hydroxylation of C7 in competition with cyclization by the second ferryl complex is not enhanced in 2H2O solvent, suggesting that the C2 hydroxyl is deprotonated prior to C7-H cleavage. These observations are consistent with the coordination of the C2 oxygen to the ferryl complex, which may reorient its oxo ligand, the substrate, or both to positions more favorable for C7-H cleavage and oxacyclization.
Subject(s)
Iron , Ketoglutaric Acids , Ketoglutaric Acids/metabolism , Ketoglutaric Acids/chemistry , Iron/metabolism , Iron/chemistry , Hydroxylation , Cyclization , Oxygenases/metabolism , Oxygenases/chemistry , Bacterial Proteins/metabolism , Bacterial Proteins/chemistryABSTRACT
The role of the cerebellum in amnestic mild cognitive impairment (aMCI), typically a prodromal stage of Alzheimer's disease, is not fully understood. We studied the lobule-specific cerebello-cerebral connectivity in 15 cognitively normal and 16 aMCI using resting-state functional MRI. Our analysis revealed weaker connectivity between the cognitive cerebellar lobules and parietal lobe in aMCI. However, stronger connectivity was observed in the cognitive cerebellar lobules with certain brain regions, including the precuneus cortex, posterior cingulate gyrus, and caudate nucleus in participants with worse cognition. Leveraging these measurable changes in cerebello-parietal functional networks in aMCI could offer avenues for future therapeutic interventions.
Subject(s)
Amnesia , Cerebellum , Cognitive Dysfunction , Magnetic Resonance Imaging , Parietal Lobe , Humans , Cognitive Dysfunction/physiopathology , Cognitive Dysfunction/diagnostic imaging , Male , Female , Aged , Cerebellum/diagnostic imaging , Cerebellum/physiopathology , Parietal Lobe/physiopathology , Parietal Lobe/diagnostic imaging , Amnesia/physiopathology , Amnesia/diagnostic imaging , Neural Pathways/physiopathology , Neural Pathways/diagnostic imaging , Neuropsychological Tests , Middle AgedABSTRACT
Cerebellum is a key-structure for the modulation of motor, cognitive, social and affective functions, contributing to automatic behaviours through interactions with the cerebral cortex, basal ganglia and spinal cord. The predictive mechanisms used by the cerebellum cover not only sensorimotor functions but also reward-related tasks. Cerebellar circuits appear to encode temporal difference error and reward prediction error. From a chemical standpoint, cerebellar catecholamines modulate the rate of cerebellar-based cognitive learning, and mediate cerebellar contributions during complex behaviours. Reward processing and its associated emotions are tuned by the cerebellum which operates as a controller of adaptive homeostatic processes based on interoceptive and exteroceptive inputs. Lobules VI-VII/areas of the vermis are candidate regions for the cortico-subcortical signaling pathways associated with loss aversion and reward sensitivity, together with other nodes of the limbic circuitry. There is growing evidence that the cerebellum works as a hub of regional dysconnectivity across all mood states and that mental disorders involve the cerebellar circuitry, including mood and addiction disorders, and impaired eating behaviors where the cerebellum might be involved in longer time scales of prediction as compared to motor operations. Cerebellar patients exhibit aberrant social behaviour, showing aberrant impulsivity/compulsivity. The cerebellum is a master-piece of reward mechanisms, together with the striatum, ventral tegmental area (VTA) and prefrontal cortex (PFC). Critically, studies on reward processing reinforce our view that a fundamental role of the cerebellum is to construct internal models, perform predictions on the impact of future behaviour and compare what is predicted and what actually occurs.
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INTRODUCTION: Oral hygiene for individuals with disabilities living at home heavily relies on caregiver assistance. This study investigates differences in mouth opening, dental plaque index and halitosis grade among home-dwelling individuals with and without oral massage intervention. It is important to consider that extended bedridden periods, the presence of nasogastric tubes and difficulties in mouth opening can affect caregivers' oral cleaning effectiveness. METHOD: This single-blind controlled experiment spanned 12 weeks. Primary caregivers underwent a 15- to 20-min demonstration. The experimental group received guidance on the Bass brushing method, instructions for using oral cleaning tools and training in oral massage. The control group received guidance on the Bass brushing method and instructions for oral cleaning tools. Measurement tools included basic participant information, oral examination records, mouth opening assessments, dental plaque index evaluations and halitosis ratings. RESULTS: The study included 38 subjects, all over 80 years old with disabilities. Dental plaque index significantly improved after massage (p = 0.001). Compared to their pre-massage conditions, the experimental group showed significant improvements in maximum mouth opening (11.65-20.71 mm, p = 0.001), dental plaque index (98.04%-59.74%, p < 0.0001) and halitosis rating (4.12-3.76, p = 0.034). CONCLUSIONS: Oral massage effectively improved mouth opening, reduced the dental plaque index and lowered halitosis ratings in the experimental group, underscoring its positive impact on oral hygiene. The study's insights can significantly benefit oral care for individuals with disabilities living at home.
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BACKGROUND: Male hypogonadism is not uncommon in people with HIV (PWH), with estimated prevalence ranging from 9% to 16%. Existing data are limited on the serum testosterone levels in PWH in Asian populations. METHODS: We enrolled HIV-positive men who have sex with men (MSM) and had been on stable antiretroviral therapy and MSM without HIV between February 2021 and November 2022. Serum free testosterone levels, sex hormone-binding globulins and other associated hormones were measured. Multiple linear regression analysis was performed to assess the association between serum free testosterone levels and clinical variables collected. RESULTS: A total of 447 MSM with HIV and 124 MSM without HIV were enrolled. Compared with MSM without HIV, MSM with HIV had a higher age (median, 41 versus 29.5 years) and prevalence of symptomatic hypogonadism (8.3% versus 1.6%). Among MSM who were aged <35 years, there were no significant differences in the serum free testosterone levels and prevalences of hypogonadism between the two groups. In multiple linear regression analysis, serum free testosterone level significantly decreased with advanced age (a decrease of 1.14 pg/mL per 1-year increase) and a higher body-mass index (BMI) (a decrease of 1.07 pg/mL per 1-kg/m2 increase), but was not associated with HIV serostatus. CONCLUSION: We found that MSM with HIV had a higher prevalence of symptomatic hypogonadism than MSM without HIV in Taiwan, which could be attributed to age difference. Serum free testosterone levels were negatively correlated with age and BMI, but did not show a significant correlation with HIV serostatus.