ObjectivePhotoacoustic pump-probe imaging can effectively eliminate the interference of blood background signal in traditional photoacoustic imaging, and realize the imaging of weak phosphorescence molecules and their triplet lifetimes in deep tissues. However, background differential noise in photoacoustic pump-probe imaging often leads to large fitting results of phosphorescent molecule concentration and triplet lifetime. Therefore, this paper proposes a novel triplet lifetime fitting method for photoacoustic pump-probe imaging. By extracting the phase of the triplet differential signal and the background noise, the fitting bias caused by the background noise can be effectively corrected. MethodsThe advantages and feasibility of the proposed algorithm are verified by numerical simulation, phantom and in vivo experiments, respectively. ResultsIn the numerical simulation, under the condition of noise intensity being 10% of the signal amplitude, the new method can optimize the fitting deviation from 48.5% to about 5%, and has a higher exclusion coefficient (0.88>0.79), which greatly improves the fitting accuracy. The high specificity imaging ability of photoacoustic pump imaging for phosphorescent molecules has been demonstrated by phantom experiments. In vivo experiments have verified the feasibility of the new fitting method proposed in this paper for fitting phosphoometric lifetime to monitor oxygen partial pressure content during photodynamic therapy of tumors in nude mice. ConclusionThis work will play an important role in promoting the application of photoacoustic pump-probe imaging in biomedicine.

ObjectiveAs a second messenger in intracellular signal transduction, Ca²⁺ plays an important role in cell migration. Previous studies have demonstrated that extracellular Ca²⁺ influx can promote electric field-guided cell migration, known as electrotaxis. However, the effect of intracellular Ca²⁺ flow on electrotaxis is unclear. Therefore, in this study, we investigate the effect of Ca²⁺ flux on the electrotaxis of Dictyostelium discoideum. MethodsThe electrotaxis of Dictyostelium discoideum was investigated by applying a direct current (DC) electric field. Cell migration was recorded using a real-time imaging system. Calcium channel inhibitors, the extracellular Ca²⁺ chelator EGTA, Ca²⁺-free DB buffer, and caffeine were applied to investigate the impact of intra- and extracellular Ca²⁺ flow on electrotaxis. The involvement of G proteins and ERK2 in directed cell migration mediated by endoplasmic reticulum Ca²⁺ release was explored using mutants. ResultsDictyostelium discoideum migrated toward the cathode in the electric field in a voltage-dependent manner. The intracellular Ca²⁺ concentration of the cells was significantly increased in the electric field. Inhibition of both extracellular Ca²⁺ influx and intracellular Ca²⁺ release suppressed cell electrotaxis migration. Inhibition of endoplasmic reticulum Ca²⁺ release induced by caffeine significantly impaired the electrotaxis of Dictyostelium discoideum. Deletion of Gα2, Gβ, Gγ, and Erk2 notably reduced the electrotaxis of the cells. Enhancing Ca²⁺ release mediated by caffeine restored the electrotaxis of the Gα2^-, Gβ ^-, and Erk2^- mutant cells partially or completely, but did not restore electrotaxis in the Gγ^- mutant cells. ConclusionCa²⁺ release from the endoplasmic reticulum regulates electrotaxis migration in Dictyostelium discoideum and is involved in the regulation of cell electrotaxis by G proteins and ERK2.

The innate immune response is the first line of defense for the host against viral infections. Targeted degradation of pathogenic microorganisms through autophagy, in conjunction with pattern recognition receptors synergistically inducing the production of interferon (IFN), constitutes an important pathway for the body to resist viral infections. Rubicon, a Run domain Beclin 1-interacting and cysteine-rich domain protein, has an inhibitory effect on autophagy and IFN production. On the one hand, Rubicon, as a component of the phosphoinositide 3-kinase (PI3K) complex, interacts with different domains of vacuolar protein sorting 34 (Vps34), ultraviolet radiation resistance associated gene (UVRAG), guanosine triphosphate (GTP) kinase, and RAS oncogene family member 7 (Rab7) to mediate the inhibition of autophagy maturation; on the other hand, Rubicon inhibits the ubiquitination of nuclear factor κB essential modulator (NEMO) and the dimerization of interferon regulatory factor 3 (IRF3), thereby blocking the signal transduction related to IFN production. Research has revealed that various viruses, such as Kaposi's sarcoma-associated herpesvirus (KSHV), hepatitis B virus (HBV), Sendai virus (SeV), and hepatitis C virus (HCV), achieve innate immune evasion by regulating the expression or function of Rubicon. Rubicon is expected to be a new target for antiviral therapy.
Humans ; Autophagy/immunology* ; Immunity, Innate ; Interferons/immunology* ; Immune Evasion ; Animals ; Virus Diseases/virology* ; Signal Transduction ; Viruses/immunology* ; Intracellular Signaling Peptides and Proteins/immunology* ; Autophagy-Related Proteins

PURPOSE: Assessing fluid responsiveness relying on central venous oxygen saturation (ScvO₂) yields varied outcomes across several studies. This study aimed to determine the ability of the change in ScvO₂ (ΔScvO₂) to detect fluid responsiveness in ventilated septic shock patients and potential influencing factors. METHODS: In this prospective, single-center study, all patients conducted from February 2023 to January 2024 received fluid challenge. Oxygen consumption was measured by indirect calorimetry, and fluid responsiveness was defined as an increase in cardiac index (CI) ≥ 10% measured by transthoracic echocardiography. Multivariate linear regression analysis was conducted to evaluate the impact of oxygen consumption, arterial oxygen saturation, CI, and hemoglobin on ScvO₂ and its change before and after fluid challenge. The Shapiro-Wilk test was used for the normality of continuous data. Data comparison between fluid responders and non-responders was conducted using a two-tailed Student t-test, Mann Whitney U test, and Chi-square test. Paired t-tests were used for normally distributed data, while the Wilcoxon signed-rank test was used for skewed data, to compare data before and after fluid challenge. RESULTS: Among 49 patients (31 men, aged (59 ± 18) years), 27 were responders. The patients had an acute physiology and chronic health evaluation II score of 24 ± 8, a sequential organ failure assessment score of 11 ± 4, and a blood lactate level of (3.2 ± 3.1) mmol/L at enrollment. After the fluid challenge, the ΔScvO₂ (mmHg) in the responders was greater than that in the non-responders (4 ± 6 vs. 1 ± 3, p = 0.019). Multivariate linear regression analysis suggested that CI was the only independent influencing factor of ScvO₂, with R² = 0.063, p = 0.008. After the fluid challenge, the change in CI became the only contributing factor to ΔScvO₂ (R² = 0.245, p < 0.001). ΔScvO₂ had a good discriminatory ability for the responders and non-responders with a threshold of 4.4% (area under the curve = 0.732, p = 0.006). CONCLUSION ΔScvO₂ served as a reliable surrogate marker for ΔCI and could be utilized to assess fluid responsiveness, given that the change in CI was the sole contributing factor to the ΔScvO₂. In stable hemoglobin conditions, the absolute value of ScvO₂ could serve as a monitoring indicator for adequate oxygen delivery independent of oxygen consumption.
Humans ; Shock, Septic/blood* ; Male ; Female ; Middle Aged ; Prospective Studies ; Oxygen Saturation ; Aged ; Fluid Therapy ; Oxygen/blood* ; Oxygen Consumption ; Adult

PURPOSE: To investigate the incidence and influencing factors of bone loss in patients with spinal cord injury (SCI). METHODS: A retrospective case-control study was conducted. Patients with SCI in our hospital from January 2019 to March 2023 were collected. According to the correlation between bone mineral density (BMD) at different sites, the patients were divided into the lumbar spine group and the hip joint group. According to the BMD value, the patients were divided into the normal bone mass group (t > -1.0 standard deviation) and the osteopenia group (t ≤ -1.0 standard deviation). The influencing factors accumulated as follows: gender, age, height, weight, cause of injury, injury segment, injury degree, time after injury, start time of rehabilitation, motor score, sensory score, spasticity, serum value of alkaline phosphatase, calcium, and phosphorus. The trend chart was drawn and the influencing factors were analyzed. SPSS 26.0 was used for statistical analysis. Correlation analysis was used to test the correlation between the BMD values of the lumbar spine and bilateral hips. Binary logistic regression analysis was used to explore the influencing factors of osteoporosis after SCI. p < 0.05 was considered statistically significant. RESULTS: The incidence of bone loss in patients with SCI was 66.3%. There was a low concordance between bone loss in the lumbar spine and the hip, and the hip was particularly susceptible to bone loss after SCI, with an upward trend in incidence (36% - 82%). In this study, patients with SCI were divided into the lumbar spine group (n = 100) and the hip group (n = 185) according to the BMD values of different sites. Then, the lumbar spine group was divided into the normal bone mass group (n = 53) and the osteopenia group (n = 47); the hip joint group was divided into the normal bone mass group (n = 83) and the osteopenia group (n = 102). Of these, lumbar bone loss after SCI is correlated with gender and weight (p = 0.032 and < 0.001, respectively), and hip bone loss is correlated with gender, height, weight, and time since injury (p < 0.001, p = 0.015, 0.009, and 0.012, respectively). CONCLUSIONS The incidence of bone loss after SCI was high, especially in the hip. The incidence and influencing factors of bone loss in the lumbar spine and hip were different. Patients with SCI who are male, low height, lightweight, and long time after injury were more likely to have bone loss.
Humans ; Spinal Cord Injuries/complications* ; Male ; Female ; Retrospective Studies ; Incidence ; Adult ; Bone Density ; Middle Aged ; Case-Control Studies ; Osteoporosis/etiology* ; Lumbar Vertebrae ; Bone Diseases, Metabolic/etiology* ; Aged ; Risk Factors

Objective:To compare the efficacy of Wnt3a factor and small molecule compound CHIR99021 in culturing colorectal cancer organoid, and to explore the feasibility of replacing Wnt3a with CHIR99021.Methods:The organoids were cultured using 2 culture systems containing Wnt3a or CHIR99021, based on the colorectal cancer cell line HCT116 and rectal cancer tissue from one patient (surgical specimen from the Department of Gastrointestinal Surgery, Zhongshan Hospital Affiliated to Dalian University), including Wnt3a cell organoid, CHIR99021 cell organoid, Wnt3a tissue organoid, and CHIR99021 tissue organoid. The growth of organoids was observed under the optical microscope. The pathological characteristics of organoids and the rectal cancer tissue were analyzed by hematoxylin-eosin (HE) staining and immunohistochemical (IHC) staining, which included cytokeratin(CK) 7, CK20, Ki-67, and stemness marker CD133. The expression of β-catenin (a key Wnt pathway protein) was analyzed by Western blotting (WB) method. The half maximal inhibitory concentration (IC50) values of Wnt3a and CHIR99021 cell organoids were analyzed by drug susceptible test and GraphPad Prism 9.0 software. Independent sample- t test was used for statistical analysis. Results:Under the optical microscope, the size of CHIR99021 cell organoid was relatively uniform, while the size of the Wnt3a cell organoid was uneven, compact and dense spherical structure was formed in both organoids. HE staining showed tumor features including increased nuclear-cytoplasmic ratio and obvious nuclear atypia in the Wnt3a and CHIR99021 cell organoids. The results of IHC staining showed that CK7 was negative, and CK20 and Ki-67 were positive in the Wnt3a and CHIR99021 cell organoids. The results of WB method showed that the relative expression level of β-catenin of the CHIR99021 cell organoid was higher than that of the Wnt3a cell organoid (0.89±0.09 vs. 0.26±0.04), and the difference was statistically significant ( t=13.80, P<0.001). The results of drug susceptible test demonstrated that the IC50 value of the Wnt3a and CHIR99021 cell organoid was 10.91 and 14.55 μmol/L, respectively. Further IHC staining showed that CD133 was positive in the Wnt3a and CHIR99021 cell organoids, with stronger intensity in the CHIR99021 cell organoid. The pathological characteristics of Wnt3a and CHIR99021 tissue organoid were consistent with those of the rectal cancer tissue of the patient, with all CK7 being negative and CK20 and Ki-67 being positive. Conclusions:Both Wnt3a and CHIR99021 can successfully establish colorectal cancer organoids with consistent pathological characteristics. The IC50 value of the CHIR99021 cell organoid is high, which is related to the increased stemness of organoids. The pathological characteristics of Wnt3a and CHIR99021 tissue organoid are consistent with those of the rectal cancer tissue from the patient.

Depression is a heterogeneous mental disorder in which the interaction between genetic susceptibility and environ-mental factors plays a key role in its pathogenesis.Although the specific mechanisms of the disease still need to be thoroughly studied and elucidated,there is now a broad consensus that epi-genetic markers have a central influence on its mechanism of ac-tion.DNA methylation of brain-derived neurotrophic factor(BD-NF)is not only regarded as a promising epigenetic biomarker of pathology,but may also help predict the efficacy of antidepres-sants.In this paper we reviewed the gene structure of BDNF and its DNA methylation regulation mechanism,and also analyzed the changes of DNA methylation of this factor in depression pa-tients and animal models,aiming to provide new ideas and theo-retical support for clinical research.

Objective:To evaluate the effectiveness of yttrium aluminum garnet (Nd∶YAG) laser vitreolysis in the treatment of symptomatic vitreous opacity.Methods:An observational case series study was performed.Forty-four eyes of 44 patients diagnosed as physiological vitreous opacity in Shenzhen Eye Hospital from June 2021 to September 2022 and treated with Nd∶YAG laser vitreolysis were enrolled.Before treatment and 2 months after last treatment, best corrected visual acuity (BCVA) evaluated with standard logarithmic visual acuity chart, floater areas calculated through infrared fundus photography, and objective scattering index (OSI) obtained by the Optical Quality Analysis System (OQAS) were recorded.The occurrence of complications during the follow-up period was recorded.The differences in each indicator were compared, and a simple linear regression model was used to analyze the relationship between floater area and OSI.This study adhered to the Declaration of Helsinki and was approved by the Medical Ethics Committee of Shenzhen Eye Hospital (No.2021-6-3).Patients were informed of the study methods and purposes.Written informed consent was obtained from each subject.Results:There was no significant difference in BCVA before and after Nd∶YAG laser vitreolysis ( t=-0.478, P=0.635).The floater area before laser treatment was (3.043±1.942)mm 2, which was significantly larger than (1.074±0.735)mm 2 after laser treatment ( t=0.769, P<0.001).The OSI before laser treatment was 1.976±0.975, which was significantly greater than 1.560±0.796 after laser treatment ( t=0.730, P<0.001).The results of linear regression analysis showed that the OSI=1.45+ 0.16× floater area ( F=5.681, P=0.020).No patient had visual acuity loss or intraocular pressure increase and no traumatic cataract or retinal damage occurred. Conclusions:After laser treatment, the floater area decreased, the OSI decreased, and the visual quality of patients improved.The OSI from OQAS Ⅱ and floater area can be used as quantitative evaluation indicators to objectively evaluate the effectiveness of Nd∶YAG laser vitreolysis.

OBJECTIVES: To investigate the molecular mechanism by which He's Yangchao Formula improves ovarian function in premature ovarian insufficiency (POI) mice through intestinal flora modulation. METHODS: Forty female ICR mice (aged 6-8 weeks) were intraperitoneally injected with cyclophosphamide (150 mg/kg) to establish a POI model, while 10 untreated mice served as the blank control. Successfully modeled mice were randomly divided into four groups (n=10/group): low-dose He's Yangchao Formula (6 g crude herb/kg), high-dose He's Yangchao Formula (25 g crude herb/kg), positive control (estradiol), and model control (distilled water). Treatments were admin-istered daily by gavage for 6 weeks. Vaginal exfoliated cells were stained with Wright-Giemsa solution to monitor estrous cycles. Serum estradiol and follicle-stimulating hormone (FSH) levels were measured by ELISA. Ovarian FSH receptor (FSHR) expression was assessed by immunohistochemistry. Glycolysis-related proteins pyruvate kinase M2 (PKM2) and glucose transporter 4 (GLUT4) were analyzed by Western blotting and immuno-fluorescence. Fecal samples from blank control, model control, and high-dose groups underwent metagenomic sequencing to evaluate intestinal microbiota diversity and com-position. RESULTS: He's Yangchao Formula restored estrous cyclicity, increased serum estradiol (P<0.05), decreased serum FSH (P<0.05), and upregulated FSHR expression in granulosa cells (P<0.05). Metagenomic analysis revealed significant structural differences in intestinal flora among blank control, model control, and high-dose groups (P<0.01). The high-dose group showed reduced abundance of conditional pathogens (e.g., Alistipes, Prevotella, Odoribacter, Blautia, Rikenella) compared to the model control (P<0.05). Functional enrichment analysis indicated involvement of glycolysis-related pathways. Concordantly, PKM2 and GLUT4 expression was downregulated in the model control but upregulated in He's Yangchao Formula groups (P<0.05). CONCLUSIONS He's Yangchao Formula ameliorates POI in mice by remodeling intestinal flora structure, enhancing glycolytic activity, improving ovarian sex hormone secretion, increasing granulosa cell FSHR expression, and restoring estrous cyclicity.

Extracellular vesicles (EVs) are membrane-bound vesicles secreted by cells, including exosomes, microvesicles, and apoptotic bodies, which play critical roles in intercellular communication, material transport, and signal transduction. In recent years, increasing evidence has highlighted the essential function of EVs in early embryo development. By carrying bioactive molecules such as proteins, nucleic acids (e.g., mRNA and miRNA), and lipids, EVs regulate embryonic gene expression, cell proliferation, differentiation, and the microenvironment. Studies have shown that EVs derived from various segments of the female reproductive tract can enhance embryonic developmental potential, improve embryo quality, and facilitate implantation. Additionally, EVs secreted by embryos themselves participate in intercellular communication and play pivotal roles during embryogenesis. This review summarizes recent advances in understanding the functions of EVs in early embryo development, discusses their roles in mediating cell-cell communication and regulating gene expression, and explores their potential applica-tions in reproductive medicine and clinical practice, offering new perspectives for optimizing assisted reproductive technologies.