Impact of minimally invasive surgery on immune function and stress response in gastric cancer patients.

BACKGROUND: Gastric cancer remains a leading cause of cancer-related mortality globally. Traditional open surgery for gastric cancer is often associated with significant morbidity and prolonged recovery. AIM: To evaluate the effectiveness of laparoscopic minimally invasive surgery as an alternative to traditional open surgery for gastric cancer, focusing on its potential to reduce trauma, accelerate recovery, and achieve comparable oncological outcomes. METHODS: This study retrospectively analyzed 203 patients with gastric cancer who underwent surgery at the Shanghai Health Medical College Affiliated Chongming Hospital from January 2020 to December 2023. The patients were divided into two groups: Minimally invasive surgery group (n = 102), who underwent laparoscopic gastrectomy, and open surgery group (n = 101), who underwent traditional open gastrectomy. We compared surgical indicators (surgical incision size, intraoperative blood loss, surgical duration, and number of lymph nodes dissected), recovery parameters (time to first flatus, time to start eating, time to ambulation, and length of hospital stay), immune function (levels of IgA, IgG, and IgM), intestinal barrier function (levels of D-lactic acid and diamine oxidase), and stress response (levels of C-reactive protein, interleukin-6, and procalcitonin). RESULTS: The minimally invasive surgery group demonstrated significantly better outcomes in terms of surgical indicators, including smaller incisions, less blood loss, shorter surgery time, and more lymph nodes dissected (P < 0.05 for all). Recovery was also faster in the minimally invasive surgery group, with earlier return of bowel function, earlier initiation of diet, quicker mobilization, and shorter hospital stays (P < 0.05 for all). Furthermore, patients in the minimally invasive surgery group had better preserved immune function, superior intestinal barrier function, and a less pronounced stress response postoperatively (P < 0.05 for all). CONCLUSION: Laparoscopic minimally invasive surgery for gastric cancer not only provides superior surgical indicators and faster recovery but also offers advantages in preserving immune function, protecting intestinal barrier function, and mitigating the stress response compared to traditional open surgery. These findings support the broader adoption of laparoscopic techniques in the management of gastric cancer.

Antitumor effects of a Sb-rich polyoxometalate on non-small-cell lung cancer by inducing ferroptosis and apoptosis.

Polyoxometalates (POMs) are a class of anionic metal-oxygen clusters with versatile biological activities. Over the past decade, an increasing number of POMs, especially Sb-rich POMs, have been proven to exert antitumor activity. However, the antitumor effects and mechanisms of POMs in the treatment of non-small cell lung cancer (NSCLC) remain largely unexplored. This study employed a Sb-rich {Sb21Tb7W56} POM (POM-1) for NSCLC therapy and investigated its mechanism of action. Our results demonstrated that POM-1 exhibited cytotoxicity against H1299 and A549 cells with IC50 values of 3.245 µM and 3.591 µM, respectively. The migration and invasion were also inhibited by 28.05% and 76.18% in H1299 cells, as well as 36.88% and 36.98% in A549 cells at a concentration of 5 µM. In a tumor xenograft mouse model, POM-1 suppressed tumor growth by 76.92% and 84.62% at doses of 25 and 50 mg kg-1, respectively. Transcriptomic analysis indicated the alteration of ferroptosis and apoptosis signaling pathways in POM-treated NSCLC cells. Subsequent experimentation confirmed the induction of ferroptosis, evidenced by 5.6-fold elevated lipid peroxide levels with treatment of 5 µM POM-1, alongside increased expression of ferroptosis-associated proteins. Additionally, the apoptosis induced by POM-1 was also validated by the 19.67% and 30.1% increase in apoptotic cells in H1299 and A549 cells treated with 5 µM POM-1, respectively, as well as the upregulated activation of caspase-3. In summary, this study reveals, for the first time, ferroptosis as the antitumor mechanism of Sb-rich POM, and that synergism with ferroptosis and apoptosis is a highly potent antitumor strategy for POM-based antitumor therapy.

Prognostic significance of oligodendrocyte transcription factor 2 expression in glioma patients: A systematic review and meta-analysis.

BACKGROUND: Gliomas are the most common primary central nervous system neoplasm. Despite recent advances in the diagnosis and treatment of gliomas, patient prognosis remains dismal. Therefore, it is imperative to identify novel diagnostic biomarkers and therapeutic targets of glioma to effectively improve treatment outcomes. AIM: To investigate the association between oligodendrocyte transcription factor 2 (Olig2) expression and the outcomes of glioma patients. METHODS: The PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure databases were searched for studies (published up to October 2023) that investigated the relationship between Olig2 expression and prognosis of glioma patients. The quality of the studies was assessed using the Newcastle Ottawa Scale. Data analyses were performed using Stata Version 12.0 software. RESULTS: A total of 1205 glioma patients from six studies were included in the meta-analysis. High Olig2 expression was associated with better outcomes in glioma patients [hazard ratio (HR): 0.81; 95% (confidence interval) CI: 0.51-1.27; P = 0.000]. Furthermore, the results of subgroup meta-analysis showed that high expression of Olig2 was associated with poor overall survival in European patients (HR: 1.34; 95%CI: 0.79-2.27) and better prognosis in Asian patients (HR: 0.43; 95%CI: 0.22-0.84). The sensitivity analysis showed that no single study had a significant effect on pooled HR, and there was also no indication of publication bias according to the Egger's and Begger's P value test or funnel plot test. CONCLUSION: High Olig2 expression may have a positive impact on the prognosis of glioma patients, and should be investigated further as a prognostic biomarker and therapeutic target for glioma.

Effect of phytohormones on the carbon sequestration performance of CO2 absorption-microalgae conversion system under low light restriction.

Microalgae have the potential to fix CO2 into valuable compounds. Low photosynthetic efficiency caused by low light was one of the challenges faced by microalgae carbon sequestration. In this study, Melatonin (MT) and indole-propionic acid (IPA) were used to alleviate the growth inhibition of Spirulina in CAMC system under low light restriction. The results showed that MT and IPA increased biomass and carbon fixation capacity. 10 mg/L IPA group achieved the maximum biomass and carbon fixation capacity, which were 17.11% and 21.46% higher than control. MT and IPA promoted the synthesis of chlorophyll, which in turn captured more light energy for microalgae growth. The increase of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) activities enhanced the resistance of microalgae to low light stress. MT and IPA promoted the secretion of extracellular polymeric substances (EPS) which was benefit to protect cells. The maximum phycocyanin content and yield was found in 10 mg-IPA group, which was 20.67% and 46.67% higher than control. MT and IPA improved the synthesis of carbohydrates and proteins and increased carbohydrates and proteins yield. This indicated that adding phytohormones was an effective method to alleviate the growth of microalgae restricted by low light stress, which provided a theoretical guidance for the application of CAMC system in CO2 capture and resource utilization.

Exploring the impact of pre-anastomosis cerebral microcirculation on cerebral hyperperfusion syndrome in superficial temporal artery-middle cerebral artery bypass surgery of moyamoya disease.

Significance: Cerebral hyperperfusion syndrome (CHS), characterized by neurologic deficits due to postoperative high cerebral perfusion, is a serious complication of superficial temporal artery-middle cerebral artery (STA-MCA) surgery for moyamoya disease (MMD). Aim: We aim to clarify the importance of assessing pre-anastomosis cerebral microcirculation levels by linking the onset of CHS to pre- and post-anastomosis hemodynamics. Approach: Intraoperative laser speckle contrast imaging (LSCI) measured changes in regional cerebral blood flow (rCBF) and regional blood flow structuring (rBFS) within the cerebral cortical microcirculation of 48 adults with MMD. Results: Following anastomosis, all MMD patients exhibited a significant increase in rCBF ( 279.60 % ± 120.00 % , p < 0.001 ). Changes in rCBF and rBFS showed a negative correlation with their respective baseline levels (rCBF, p < 0.001 ; rBFS, p = 0.005 ). Baseline rCBF differed significantly between CHS and non-CHS groups ( p = 0.0049 ). The areas under the receiver operating characteristic (ROC) curve for baseline rCBF was 0.753. Hemorrhagic MMD patients showed higher baseline rCBF than ischemic patients ( p = 0.036 ), with a marked correlation between pre- and post-anastomosis rCBF in hemorrhagic cases ( p = 0.003 ), whereas ischemic MMD patients did not. Conclusion: Patients with low levels of pre-anastomosis baseline CBF induce a dramatic increase in post-anastomosis and show a high risk of postoperative CHS.

Development and validation of a prognostic nomogram for esophageal cancer patients based on SEER Asian population.

This study aims to develop and validate a nomogram for predicting overall survival (OS) in Asian patients with Esophageal Cancer (EC). Data from Asian EC patients were collected from the Surveillance, Epidemiology, and End Results (SEER) database. The patients were randomly divided into training and validation cohorts in a 7:3 ratio. The Least Absolute Shrinkage and Selection Operator (LASSO) regression was used for initial variable selection, followed by multivariate Cox regression analysis to identify independent prognostic factors. A nomogram was subsequently constructed based on these factors. The predictive performance of the nomogram was evaluated using receiver operating characteristic (ROC) curves and calibration curves, while the clinical utility of the nomogram was assessed through decision curve analysis (DCA). The LASSO regression and multivariate Cox regression analysis identified age, sex, marital status, tumor size, M stage, surgery, and chemotherapy as independent prognostic factors. The ROC curve results demonstrated that the area under the curve (AUC) values for predicting 1-year, 3-year, and 5-year OS in the training cohort were 0.770, 0.756, and 0.783, respectively. In the validation cohort, the AUC values were 0.814, 0.763, and 0.771, respectively. Calibration curves indicated a high concordance between predicted and actual OS. The DCA demonstrated that the nomogram has significant clinical applicability. This nomogram provides reliable predictions and valuable guidance for personalized survival estimates and high-risk patient identification.

Risk factors and prognostic factors associated with retinal detachment and visual outcomes in acute retinal necrosis.

OBJECTIVE: To investigate the risk factors and prognostic factors that affect the long-term clinical outcomes of acute retinal necrosis (ARN). METHODS: A retrospective study of patients with ARN who underwent treatment and completed follow-up in our ophthalmology department from 2011 to 2021 was conducted. The incidence and risk factors of retinal detachment (RD) and prognostic factors affecting long-term clinical outcomes, such as late-onset RD and final vision loss (< 20/200), were analyzed. RESULTS: Totally 59 ARN patients (65 eyes) with an average follow-up of 48.9 months were enrolled. During the follow-up period, RD occurred in 34 eyes (52.3%). The risk factors for RD included quadrants of involved retinal necrosis (odds ratio [OR], 4.181; 95% confidence interval [CI], 1.950-10.834) and initial intraocular viral load (OR, 1.721; 95% CI, 1.071-3.083). Early intravitreal antiviral treatment (OR, 1.204; 95% CI, 1.040-1.480) was independently associated with a decreased risk of late-onset RD. The factors independently associated with an increased risk of final vision loss were worse initial visual acuity (OR, 3.895; 95% CI, 1.551-13.662) and late-onset RD (OR, 8.043; 95% CI, 1.380-67.216). In addition, we utilized the fluctuating magnitude of viral load to quantify the extent of its reduction in comparison to its original value following the initial intravitreal antiviral injection (IAI). This ratio was strongly related to initial intraocular IL-8 concentration (Spearman correlation coefficient=-0.741, P = 0.000) and moderately related to the initial degree of aqueous flare (Spearman correlation coefficient=-0.508, P = 0.010). CONCLUSION: RD is a common and severe complication of ARN with multiple risk factors, such as initial retinitis involvement area and initial intraocular viral load. Active local antiviral therapy may reduce the risk of late-onset RD. The antiviral medication should be adjusted according to the inflammatory state. Therefore, timely detection of causative viruses and intensive systemic and local antiviral therapy is crucial for preserving visual function in ARN patients.

Rapid progress of an iris metastasis from esophageal cancer: a case report and review of literature.

This case report details a rare instance of rapid iris metastasis from esophageal cancer in a 59-year-old man. A literature review was conducted to explore recent advances in detecting, diagnosing, and treating intraocular metastatic malignancies. Positron emission tomography-computed tomography played a crucial role in identifying primary sites and systemic metastases. Local treatment combined with systemic therapy effectively reduced tumor size, preserved useful vision, and improved the patient's survival rate. A comparison was made of the characteristics of iris metastases from esophageal cancer and lung cancer, including age, gender, tumor characteristics, and treatment. The challenges associated with diagnosis and treatment are discussed, highlighting the implications for clinical practice.

Enhancement of motor neuron development and function in zebrafish by sialyllacto-N-tetraose b.

Background: Sialyllacto-N-tetraose b (LSTb) is a component of human milk oligosaccharides. Due to its low concentration, the impact of LSTb on neurodevelopment remains largely unexplored. It is worth studying whether LSTb should be added to infant formula to simulate breast milk. This study aimed to investigate the effect of LSTb on the development of motor neurons of the central nervous system using a transgenic zebrafish model. Methods: Transgenic (Tg) zebrafish line (Hb9:GFP) was incubated with LSTb, and the axonal growth of caudal primary (CaP) neurons was assessed. Locomotor behavior was evaluated, and RNA sequencing (RNA-seq) was performed to identify the differentially expressed genes (DEGs). The expression of Slit2 and Slit3, genes involved in axon guidance, was further analyzed through real-time polymerase chain reaction (real-time PCR) and whole-mount in situ hybridization. Results: There was a significant increase in the number and length of CaP axon branches, suggesting that LSTb promotes CaP development. Behavioral analysis revealed enhanced locomotor activity in LSTb-treated larvae, indicating improved motor function. RNA-seq analysis identified 5,847 DEGs related to central nervous system neuron differentiation, including Slit2 and Slit3, which are known to contribute to axon guidance. In situ hybridization confirmed increased Slit2 expression in the central nervous system of LSTb-treated larvae. Conclusions: LSTb significantly influences motor neuron development, potentially through the upregulation of Slit2 and Slit3. This research provides valuable insights into the role of LSTb in neurodevelopment.

Adaptive self-supervised learning for sequential recommendation.

Sequential recommendation typically utilizes deep neural networks to mine rich information in interaction sequences. However, existing methods often face the issue of insufficient interaction data. To alleviate the sparsity issue, self-supervised learning is introduced into sequential recommendation. Despite its effectiveness, we argue that current self-supervised learning-based (i.e., SSL-based) sequential recommendation models have the following limitations: (1) using only a single self-supervised learning method, either contrastive self-supervised learning or generative self-supervised learning. (2) employing a simple data augmentation strategy in either the graph structure domain or the node feature domain. We believe that they have not fully utilized the capabilities of both self-supervised methods and have not sufficiently explored the advantages of combining graph augmentation schemes. As a result, they often fail to learn better item representations. In light of this, we propose a novel multi-task sequential recommendation framework named Adaptive Self-supervised Learning for sequential Recommendation (ASLRec). Specifically, our framework combines contrastive and generative self-supervised learning methods adaptively, simultaneously applying different perturbations at both the graph topology and node feature levels. This approach constructs diverse augmented graph views and employs multiple loss functions (including contrastive loss, generative loss, mask loss, and prediction loss) for joint training. By encompassing the capabilities of various methods, our model learns item representations across different augmented graph views to achieve better performance and effectively mitigate interaction noise and sparsity. In addition, we add a small proportion of random uniform noise to item representations, making the item representations more uniform and mitigating the inherent popularity bias in interaction records. We conduct extensive experiments on three publicly available benchmark datasets to evaluate our model. The results demonstrate that our approach achieves state-of-the-art performance compared to 14 other competitive methods: the hit rate (HR) improved by over 14.39%, and the normalized discounted cumulative gain (NDCG) increased by over 18.67%.

Resting-state EEG features modulated by depressive state in healthy individuals: insights from theta PSD, theta-beta ratio, frontal-parietal PLV, and sLORETA.

Depressive states in both healthy individuals and those with major depressive disorder exhibit differences primarily in symptom severity rather than symptom type, suggesting that there is a spectrum of depressive symptoms. The increasing prevalence of mild depression carries lifelong implications, emphasizing its clinical and social significance, which parallels that of moderate depression. Early intervention and psychotherapy have shown effective outcomes in subthreshold depression. Electroencephalography serves as a non-invasive, powerful tool in depression research, with many studies employing it to discover biomarkers and explore underlying mechanisms for the identification and diagnosis of depression. However, the efficacy of these biomarkers in distinguishing various depressive states in healthy individuals and in understanding the associated mechanisms remains uncertain. In our study, we examined the power spectrum density and the region-based phase-locking value in healthy individuals with various depressive states during their resting state. We found significant differences in neural activity, even among healthy individuals. Participants were categorized into high, middle, and low depressive state groups based on their response to a questionnaire, and eyes-open resting-state electroencephalography was conducted. We observed significant differences among the different depressive state groups in theta- and beta-band power, as well as correlations in the theta-beta ratio in the frontal lobe and phase-locking connections in the frontal, parietal, and temporal lobes. Standardized low-resolution electromagnetic tomography analysis for source localization comparing the differences in resting-state networks among the three depressive state groups showed significant differences in the frontal and temporal lobes. We anticipate that our study will contribute to the development of effective biomarkers for the early detection and prevention of depression.

Macrocycle-Based Supramolecular Drug Delivery Systems: A Concise Review.

Efficient delivery of therapeutic agents to the lesion site or specific cells is an important way to achieve "toxicity reduction and efficacy enhancement". Macrocycles have always provided many novel ideas for drug or gene loading and delivery processes. Specifically, macrocycles represented by crown ethers, cyclodextrins, cucurbit[n]urils, calix[n]arenes, and pillar[n]arenes have unique properties, which are different cavity structures, good biocompatibility, and good stability. Benefited from these diverse properties, a variety of supramolecular drug delivery systems can be designed and constructed to effectively improve the physical and chemical properties of guest molecules as needed. This review provides an outlook on the current application status and main limitations of macrocycles in supramolecular drug delivery systems.

Constructing a Transient Ischemia Attack Model Utilizing Flexible Spatial Targeting Photothrombosis with Real-Time Blood Flow Imaging Feedback.

Transient ischemic attack (TIA) is an early warning sign of stroke and death, necessitating suitable animal models due to the associated clinical diagnostic challenges. In this study, we developed a TIA model using flexible spatially targeted photothrombosis combined with real-time blood flow imaging feedback. By modulating the excitation light using wavefront technology, we precisely created a square light spot (50 × 250 µm), targeted at the distal middle cerebral artery (dMCA). The use of laser speckle contrast imaging (LSCI) provided real-time feedback on the ischemia, while the excitation light was ceased upon reaching complete occlusion. Our results demonstrated that the photothrombus formed in the dMCA and spontaneously recanalized within 10 min (416.8 ± 96.4 s), with no sensorimotor deficits or infarction 24 h post-TIA. During the acute phase, ischemic spreading depression occurred in the ipsilateral dorsal cortex, leading to more severe ischemia and collateral circulation establishment synchronized with the onset of dMCA narrowing. Post-reperfusion, the thrombi were primarily in the sensorimotor and visual cortex, disappearing within 24 h. The blood flow changes in the dMCA were more indicative of cortical ischemic conditions than diameter changes. Our method successfully establishes a photochemical TIA model based on the dMCA, allowing for the dynamic observation and control of thrombus formation and recanalization and enabling real-time monitoring of the impacts on cerebral blood flow during the acute phase of TIA.

Iron-Catalyzed Multicomponent C-H Alkylation of in Situ Generated Imines via Photoinduced Ligand-to-Metal Charge Transfer.

Herein, we describe a novel photoinduced iron-catalyzed strategy for multicomponent C-H alkylation of in situ generated imines. By utilizing the alkyl radicals generated through iron-mediated photocatalytic C-H activation, the imines formed in situ are further subjected to addition reactions, resulting in the synthesis of various secondary and tertiary amine products. This method is simple to operate and does not require additional oxidants. It is applicable to inert alkane substrates such as cyclic alkanes, cyclic ethers, toluene, and ketones. The reaction is also compatible with various aromatic amines, alkyl amines, halogenated aromatic amines, as well as aromatic aldehydes, alkyl aldehydes, and cinnamaldehyde, among other different types of aldehydes.

Screening and characterization of a novel linear B-cell epitope on orf virus F1L protein.

Background: Orf, also known as contagious ecthyma (CE), is an acute, contagious zoonotic disease caused by the orf virus (ORFV). The F1L protein is a major immunodominant protein on the surface of ORFV and can induce the production of neutralizing antibodies. Methods: The prokaryotic expression system was used to produce the recombinant F1L protein of ORFV, which was subsequently purified and used to immunize mice. Positive hybridoma clones were screened using an indirect enzyme-linked immunosorbent assay (ELISA). The reactivity and specificity of the monoclonal antibody (mAb) were verified through Western blot and indirect immunofluorescence (IFA). The linear antigenic epitope specific to the mAb was identified through Western blot, using truncated F1L proteins expressed in eukaryotic cells. A multiple sequence alignment of the ORFV reference strains was performed to evaluate the degree of conservation of the identified epitope. Results: After three rounds of subcloning, a mAb named Ba-F1L was produced. Ba-F1L was found to react with both the exogenously expressed F1L protein and the native F1L protein from ORFV-infected cells, as confirmed by Western blot and IFA. The mAb recognized the core epitope 103CKSTCPKEM111, which is highly conserved among various ORFV strains, as shown by homologous sequence alignment. Conclusion: The mAb produced in the present study can be used as a diagnostic reagent for detecting ORFV and as a basic tool for exploring the mechanisms of orf pathogenesis. In addition, the identified linear epitope may be valuable for the development of epitope-based vaccines.

Long-term blood pressure variability and risk of cardiovascular diseases in populations with different blood pressure status: an ambispective cohort study.

OBJECTIVE: We aimed to investigate the correlation between long-term blood pressure variability (BPV) and the risk of cardiovascular diseases (CVDs) among population with different blood pressure statuses (normotension, well-controlled hypertension, and uncontrolled hypertension). METHODS: In this ambispective cohort study, CVD-free residents aged over 50 years were consecutively enrolled from two community health service centers (CHCs) in Tianjin, China from April 2017 to May 2017. Information on blood pressure was retrospectively extracted from electronic medical records of CHCs between January 2010 and May 2017, and the occurrence of new-onset CVDs was prospectively observed during follow-up until September 2019. Long-term variation of SBP and DBP was assessed using four indicators: SD, coefficient of variation (CV), average successive variability (ASV), and average real variability (ARV). Cox proportional hazards regression model was developed to identify the potential impact of BPV on the incidence of CVDs. The receiver operating characteristic curve (ROC) was utilized to evaluate the predictive value of BPV indicators for the occurrence of CVDs. RESULTS: Of 1275 participants included, 412 (32.3%) experienced new CVD events during the median 7.7 years of follow-up, with an incidence density of 499/10 000 person-year in the whole cohort. Cox regression analysis revealed that almost all SBP and DBP variability indicators (except for SBP-SD) were significantly related to the risk of CVDs, especially among individuals with well-controlled hypertension. A trend toward an increased risk of CVDs across BPV quartiles was also observed. Moderate predictive abilities of BPV were observed, with the area under ROC curves ranging between 0.649 and 0.736. For SBP variability, SD had the lowest predictive ability, whereas for DBP variability, ARV had the lowest predictive ability. No significant association of CVDs with SBP-SD was found in all analyses, no matter as a continuous or categorical variable. CONCLUSION: Elevated long-term BPV is associated with an increased risk of CVDs, especially among individuals with well-controlled hypertension. CV and ASV had higher predictive values than SD and ARV.

Study on adsorption of kaolinite and gold thiosulfate.

The adsorption behavior of gold thiosulfate ions on the surface of kaolinite was studied using a combination of experimental research and quantum chemical calculations. Under the condition of a stirring time of 30 min, a stirring speed of 500 r·min-1, and a mass ratio of 30% kaolinite in the slurry, when the initial gold concentration of 56.50 mg·L-1,the adsorption rate of gold-thiosulfate ions from a kaolinite-containing solution was 7.44%. The results of Fourier transform infrared spectroscopy (FTIR) and energy dispersive spectroscopy (EDS) showed that the physical and chemical adsorption of kaolinite and gold thiosulfate occurred in solution. Quantum chemical calculations were performed using the CASTEP module in Materials Studio. The adsorption energy of gold thiosulfate on the surface of kaolinite (001) was calculated as - 438.01 kJ·mol-1.The calculated H76-O289 distance was 1.615 Å. Mulliken Charge population analysis and bond population analysis showed that gold thiosulfate ions form relatively stable bonds on the kaolinite surface (001). In the process of thiosulfate immersion, part of gold is adsorbed by kaolinite, which affects the extraction of gold. These results indicate that during the leaching process of gold thiosulfate, kaolinite has the ability to "catch" gold, which affects the leaching efficiency.

Ergodic speckle contrast optical coherence tomography velocimetry of rapid blood flow.

Visualizing a 3D blood flow velocity field through noninvasive imaging is crucial for analyzing hemodynamic mechanisms in areas prone to disorders. However, traditional correlation-based optical coherence tomography (OCT) velocimetry techniques have a maximum measurable flow velocity depending on the A-line rate. We presented the ergodic speckle contrast OCT (ESCOCT) to break the bottleneck in measuring the rapid blood flow velocity. It achieved a measurement of blood flow velocity ranging from 9.5 to 280 mm/s using a 100 kHz swept-source (SS) OCT based on 100 A-repeats scanning mode. Addressing the non-ergodic problem of temporal OCT signals by integrating more consecutive A-scans, ESCOCT can enable the estimation for lower velocity flows by increasing A-repeats. ESCOCT provided a wide dynamic range with no upper limit on measuring blood flow velocity with an adequate signal-to-noise ratio and improved the sensitivity and accuracy of the hemodynamic assessment.

Impact of O-acetylation on chitin oligosaccharides modulating inflammatory responses in LPS-induced RAW264.7 cells and mice.

Chitin oligosaccharides have garnered significant attention due to their biological activities, particularly their immunomodulatory properties. However, O-acetylation in chemically preparing chitin oligosaccharides seems inevitable and leads to some uncertainty on the bioactivity of chitin oligosaccharides. In this study, an O-acetyl-free chitin oligosaccharides and three different O-acetylated chitin oligosaccharides with degree of polymerization ranging from 2 to 6 were prepared using ammonia hydrolysis, and their structures and detailed components were further characterized with FTIR, NMR and MS. Subsequently, the effects of O-acetylation on the immunomodulatory activity of chitin oligosaccharides were investigated in vitro and in vivo. The results suggested that the chitin oligosaccharides with O-acetylation exhibited better inflammatory inhibition than pure chitin oligosaccharides, significantly reducing the expression of inflammatory factors, such as IL-6 and iNOS, in the LPS-induced RAW264.7 macrophage. The chitin oligosaccharides with a degree of O-acetylation of 93 % was found to effectively alleviate LPS-induced endotoxemia in mice, including serum inflammation indices reduction and damage repairment of the intestinal liver, and kidney tissues.