Membrane proteins are integral components of cellular membranes, accounting for approximately 30% of the mammalian proteome and serving as targets for 60% of FDA-approved drugs. They are critical to both physiological functions and disease mechanisms. Their functional protein-protein interactions form the basis for many physiological processes, such as signal transduction, material transport, and cell communication. Membrane protein interactions are characterized by membrane environment dependence, spatial asymmetry, weak interaction strength, high dynamics, and a variety of interaction sites. Therefore, in situ analysis is essential for revealing the structural basis and kinetics of these proteins. This paper introduces currently available in situ analytical techniques for studying membrane protein interactions and evaluates the characteristics of each. These techniques are divided into two categories: label-based techniques (e.g., co-immunoprecipitation, proximity ligation assay, bimolecular fluorescence complementation, resonance energy transfer, and proximity labeling) and label-free techniques (e.g., cryo-electron tomography, in situ cross-linking mass spectrometry, Raman spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, and structure prediction tools). Each technique is critically assessed in terms of its historical development, strengths, and limitations. Based on the authors’ relevant research, the paper further discusses the key issues and trends in the application of these techniques, providing valuable references for the field of membrane protein research. Label-based techniques rely on molecular tags or antibodies to detect proximity or interactions, offering high specificity and adaptability for dynamic studies. For instance, proximity ligation assay combines the specificity of antibodies with the sensitivity of PCR amplification, while proximity labeling enables spatial mapping of interactomes. Conversely, label-free techniques, such as cryo-electron tomography, provide near-native structural insights, and Raman spectroscopy directly probes molecular interactions without perturbing the membrane environment. Despite advancements, these methods face several universal challenges: (1) indirect detection, relying on proximity or tagged proxies rather than direct interaction measurement; (2) limited capacity for continuous dynamic monitoring in live cells; and (3) potential artificial influences introduced by labeling or sample preparation, which may alter native conformations. Emerging trends emphasize the multimodal integration of complementary techniques to overcome individual limitations. For example, combining in situ cross-linking mass spectrometry with proximity labeling enhances both spatial resolution and interaction coverage, enabling high-throughput subcellular interactome mapping. Similarly, coupling fluorescence resonance energy transfer with nuclear magnetic resonance and artificial intelligence (AI) simulations integrates dynamic structural data, atomic-level details, and predictive modeling for holistic insights. Advances in AI, exemplified by AlphaFold’s ability to predict interaction interfaces, further augment experimental data, accelerating structure-function analyses. Future developments in cryo-electron microscopy, super-resolution imaging, and machine learning are poised to refine spatiotemporal resolution and scalability. In conclusion, in situ analysis of membrane protein interactions remains indispensable for deciphering their roles in health and disease. While current technologies have significantly advanced our understanding, persistent gaps highlight the need for innovative, integrative approaches. By synergizing experimental and computational tools, researchers can achieve multiscale, real-time, and perturbation-free analyses, ultimately unraveling the dynamic complexity of membrane protein networks and driving therapeutic discovery.

Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

Objective To investigate the effect of oral fish oil on wound healing and related indexes in patients with diabetic foot ulcer(DFU).Methods A randomized,double-blind,placebo-controlled design was used to recruit 68 patients with DFU aged 18-80 years old in the hospital,and the baseline clinical data of the patients were collected.The patients were randomly divided into experimental group(32 cases,fish oil soft capsule,3 g/d)and control group(33 cases,corn oil soft capsule,3 g/d)by random number generated by Ex-cel,and the intervention lasted for 12 weeks.The primary endpoints included the proportion of complete wound healing and healing area≥50%.The secondary endpoints included wound area,healing time,inflamma-tion index,glucose metabolism index,nutrition related index and wound reinfection.Additionally,the influen-cing factors of wound healing were analyzed.Results After intervention,the proportion of complete wound healing and healing area≥50%in the experimental group was significantly higher than that in the control group(P=0.007,0.039).In the subjects with complete wound healing,the mean healing time in the experi-mental group was shorter than that in the control group,but the difference was not statistically significant(P=0.132).The reduction area of wound area in the experimental group was significantly larger than that in the control group(P=0.045).The decrease of interleukin(IL)-6 and IL-8 in the experimental group was significantly higher than that in the control group(P<0.05).There was no significant difference in the reduc-tion of C-reactive protein(CRP),tumor necrosis factor-α(TNF-α),neutrophil-to-lymphocyte ratio(NLR),glycated hemoglobin A1c(HbA1c)and platelet-to-lymphocyte ratio(PLR)between the two groups(P>0.05).The improvement of prealbumin(PA)in the experimental group was higher than that in the control group,but the difference was not statistically significant(P>0.05).Multivariate logistic regression analysis showed that oral fish oil intervention(OR=6.771,95%CI:1.787-25.652),HbA1c(OR=4.149,95%CI:1.026-16.770)and ulcer type(OR=4.319,95%CI:1.026-18.173)were the influencing factors of wound healing(P<0.05).Conclusion Oral fish oil promotes wound healing in patients with DFU,which may be re-lated to improving the level of chronic inflammation in the body.

BACKGROUND:Most of the studies on combined orthodontic-orthognathic treatment of skeletal class Ⅲ malocclusions have focused on the improvement of the patient's lateral appearance and recovery in the later stages of the treatment,while there are fewer studies observing the microcosmic nature of the alveolar bone remodeling of the lower anterior teeth. OBJECTIVE:To evaluate the therapeutic effect of lower anterior tooth decompensation and alveolar bone remodeling in patients with skeletal class Ⅲ malocclusion before and after orthodontic-orthognathic treatment based on oral X-ray lateral films and oral cone-beam CT. METHODS:From January 2015 to May 2023,15 patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgery at Qingdao Hospital of Rehabilitation University were enrolled.All patients underwent lateral cephalography and cone beam computed tomography before and after treatment.Cephalometric measurement items related to the angle and line distance,lip/lingual bone cracking length(d-La/d-Li)and bone cracking/bone fenestration of the lower anterior teeth before and after treatment were measured. RESULTS AND CONCLUSION:Lateral X-ray films showed that the amount of alveolar bone remodeling after decompensation of the lower anterior teeth showed significant changes compared to before treatment.The root of the tooth moved significantly towards the center of the alveolar bone,and the specific data was closer to normal data,but there were still some differences compared with normal individuals.Based on the cone-beam CT measurement,the bone cracking/bone fenestration length and width of the alveolar bone were improved in almost all the teeth after orthodontic-orthognathic combined treatment,alveolar bone remodeling in some teeth even reached the level of healthy individuals.Before treatment,most patients often experienced bone fenestration/cracking on the lip/lingual side of the lower incisor due to compensatory tooth growth.However,during the preoperative orthodontic stage,decompensation triggered alveolar bone remodeling and significant changes in tooth angle.Preoperative orthodontic treatment caused the upper anterior teeth to retract and the lower anterior teeth to tilt and control the root,but the amount of decompensation before surgery was often insufficient.In the orthognathic surgery stage,the jaw was removed through the positioning guide plate,the maxilla moved forward,and the mandible retreated.During the postoperative orthodontic process,the effect of fine adjustment was better.Although there is a certain degree of recurrence trend in the position of teeth and jawbones,the postoperative orthodontic treatment is closer to the normal value.

Objective To evaluate the pharmacokinetics characteristics of single-dose of Etripamil nasal spray 70 mg in healthy adult Chinese subjects.Methods This was a single-center,randomized,double-blind,placebo-controlled study.Twelve healthy adult Chinese subjects were randomized to receive single-dose of Etripamil nasal spray 70 mg(n=10)or placebo nasal spray(n=2).Blood and urine samples were collected prior and post dose.Etripamil in plasma and urine were analyzed by liquid chromatography-tandem mass spectrometry.The pharmacokinetic parameters were calculated by WinNonlin non-compartmental model.Results Following the single-dose of Etripamil nasal spray 70 mg in healthy adult Chinese subjects,the peak concentration of Etripamil in plasma was quickly attained,with a Cmax of(66.76±56.61)ng·mL-1 and a median(range)tmax of 4.00(3.00-5.00)min.The plasma concentrations of Etripamil had fallen approximately 65％from peak value at 25 min after dosing,and close to 80％within 50 min.The AUC0-last and AUC0-∞ were(3 104.16±2 654.46)and(4 048.77±2 682.38)ng·min·mL-1,respectively.The urine excretion percentage of Etripamil during 24 h was(0.01±0.01)％.Among the 12 subjects who were treated with Etripamil or placebo,10 subjects reported a total of 29 treatment-emergent adverse events(TEAEs).All of the TEAEs were mild in severity.The most common TEAEs were rhinorrhoea and lacrimation increased.Conclusion Etripamil was quickly absorbed after intranasal administration,followed by rapid distribution and elimination(not primarily excreted by renal);Etripamil 70 mg was safe and well tolerated by the healthy Chinese adult subjects.

Objective:This study aims to evaluate the quality and explore the preliminary clinical applications of a domestically developed hepatitis D virus nucleic acid quantification reagent (abbreviated as"domestic HDV RNA reagent").Methods:The sensitivity and accuracy of the reagent were evaluated in accordance with the WHO HDV RNA international standard, employing the Bio-Rad CFX Opus 96 real-time fluorescence quantitative PCR analysis system. Serial dilutions of pseudo-viruses or cell culture-derived virus were used to determine the linear range of the domestic HDV RNA reagent. Specificity was assessed using positive samples of HAV, HBV, HCV infection, and HEV national reference materials. Precision was evaluated with samples at both high and low concentrations. In a comparative analysis, 30 HDV IgG positive samples were tested using both the domestic HDV RNA reagent and the RoboGene HDV RNA kit based on the ABI 7500 FAST DX system. The Pearson correlation coefficient (r) was used to examine the correlation between the two reagents.Results:The domestic HDV RNA reagent demonstrated a high sensitivity of up to 6 IU/ml, consistent with that of the comparator reagent. The calibration curve for WHO HDV RNA standards had a slope of -3.286, with an amplification efficiency of 101.6%. The linear detection range spanned from 10 to 10 8 IU/ml for eight HDV genotypes. The domestic HDV RNA reagent exhibited exceptional specificity, without cross-reactivity observed with HAV, HBV, HCV, or HEV. Accuracy assessments at five concentration levels met the required standards, with intra-assay precision coefficient of variation ( CV) ranging from 1.20% to 4.20%, and inter-assay precision CV from 1.20% to 7.90%. The detection results for HDV IgG positive samples were highly correlated with the comparator reagent ( r=0.984, P<0.001), achieving a diagnostic accuracy of 100% compared to sequencing results. Conclusion:In this study, the domestic HDV RNA reagent possesses excellent specificity, accuracy, precision, and a broad linear range, attaining a sensitivity level on par with international reagents of the same type.

Objective To evaluate the therapeutic effect of normal mouse serum on radiation pneumonitis in mice and explore the possible mechanism.Methods Mouse models of radiation pneumonitis induced by thoracic radiation exposure were given intravenous injections of 100 μL normal mouse serum or normal saline immediately after the exposure followed by injections once every other day for a total of 8 injections.On the 15th day after irradiation,histopathological changes of the lungs of the mice were examined using HE staining,the levels of TNF-α,TGF-β,IL-1α and IL-6 in the lung tissue and serum were detected using ELISA,and the percentages of lymphocytes in the lung tissue were analyzed with flow cytometry.High-throughput sequencing of exosome miRNA was carried out to explore the changes in the signaling pathways.The mRNA expression levels of the immune-related genes were detected by qRT-PCR,and the protein expressions of talin-1,tensin2,FAK,vinculin,α-actinin and paxillin in the focal adhesion signaling pathway were detected with Western blotting.Results In the mouse models of radiation pneumonitis,injections of normal mouse serum significantly decreased the lung organ coefficient,lowered the levels of TNF-α,TGF-β,IL-1α and IL-6 in the serum and lung tissues,and ameliorated infiltration of CD45+,CD4+and Treg lymphocytes in the lung tissue(all P<0.05).The expression levels of Egfr and Pik3cd genes at both the mRNA and protein levels and the protein expressions of talin-1,tensin2,FAK,vinculin,α-actinin and paxillin were all significantly down-regulated in the mouse models after normal mouse serum treatment.Conclusion Normal mouse serum ameliorates radiation pneumonitis in mice by inhibiting the expressions of key proteins in the Focal adhesion signaling pathway.

Objective:To investigate the current situation of the use of transjugular intrahepatic portosystemic shunt (TIPS) for portal hypertension, which should aid the development of TIPS in China.Methods:The China Portal Hypertension Alliance (CHESS) initiated this study that comprehensively investigated the basic situation of TIPS for portal hypertension in China through network research. The survey included the following: the number of surgical cases, main indications, the development of Early-TIPS, TIPS for portal vein cavernous transformation, collateral circulation embolization, intraoperative portal pressure gradient measurement, commonly used stent types, conventional anticoagulation and time, postoperative follow-up, obstacles, and the application of domestic instruments.Results:According to the survey, a total of 13 527 TIPS operations were carried out in 545 hospitals participating in the survey in 2021, and 94.1% of the hospital had the habit of routine follow-up after TIPS. Most hospitals believed that the main indications of TIPS were the control of acute bleeding (42.6%) and the prevention of rebleeding (40.7%). 48.1% of the teams carried out early or priority TIPS, 53.0% of the teams carried out TIPS for the cavernous transformation of the portal vein, and 81.0% chose routine embolization of collateral circulation during operation. Most of them used coils and biological glue as embolic materials, and 78.5% of the team routinely performed intraoperative portal pressure gradient measurements. In selecting TIPS stents, 57.1% of the hospitals woulel choose Viator-specific stents, 57.2% woulel choose conventional anticoagulation after TIPS, and the duration of anticoagulation was between 3-6 months (55.4%). The limitation of TIPS surgery was mainly due to cost (72.3%) and insufficient understanding of doctors in related departments (77.4%). Most teams accepted the domestic instruments used in TIPS (92.7%).Conclusions:This survey shows that TIPS treatment is an essential part of treating portal hypertension in China. The total number of TIPS cases is far from that of patients with portal hypertension. In the future, it is still necessary to popularize TIPS technology and further standardize surgical indications, routine operations, and instrument application.

Background::Total human immunodeficiency virus (HIV) DNA and integrated HIV DNA are widely used markers of HIV persistence. Droplet digital polymerase chain reaction (ddPCR) can be used for absolute quantification without needing a standard curve. Here, we developed duplex ddPCR assays to detect and quantify total HIV DNA and integrated HIV DNA.Methods::The limit of detection, dynamic ranges, sensitivity, and reproducibility were evaluated by plasmid constructs containing both the HIV long terminal repeat (LTR) and human CD3 gene (for total HIV DNA) and ACH-2 cells (for integrated HIV DNA). Forty-two cases on stable suppressive antiretroviral therapy (ART) were assayed in total HIV DNA and integrated HIV DNA. Correlation coefficient analysis was performed on the data related to DNA copies and cluster of differentiation 4 positive (CD4 +) T-cell counts, CD8 + T-cell counts and CD4/CD8 T-cell ratio, respectively. The assay linear dynamic range and lower limit of detection (LLOD) were also assessed. Results::The assay could detect the presence of HIV-1 copies 100% at concentrations of 6.3 copies/reaction, and the estimated LLOD of the ddPCR assay was 4.4 HIV DNA copies/reaction (95% confidence intervals [CI]: 3.6-6.5 copies/reaction) with linearity over a 5-log 10-unit range in total HIV DNA assay. For the integrated HIV DNA assay, the LLOD was 8.0 copies/reaction (95% CI: 5.8-16.6 copies/reaction) with linearity over a 3-log 10-unit range. Total HIV DNA in CD4 + T cells was positively associated with integrated HIV DNA ( r = 0.76, P <0.0001). Meanwhile, both total HIV DNA and integrated HIV DNA in CD4 + T cells were inversely correlated with the ratio of CD4/CD8 but positively correlated with the CD8 + T-cell counts. Conclusions::This ddPCR assay can quantify total HIV DNA and integrated HIV DNA efficiently with robustness and sensitivity. It can be readily adapted for measuring HIV DNA with non-B clades, and it could be beneficial for testing in clinical trials.

Objective:To evaluate the efficacy and safety of antaitasvir phosphate 100 mg or 200 mg combined with yiqibuvir for 12 weeks in patients with various genotypes of chronic hepatitis C, without cirrhosis or compensated stage cirrhosis.Methods:Patients with chronic hepatitis C (without cirrhosis or compensated stage cirrhosis) were randomly assigned to the antaitasvir phosphate 100 mg+yiqibuvir 600 mg group (100 mg group) or the antaitasvir phosphate 200 mg+yiqibuvir 600 mg group (200 mg group) in a 1∶1 ratio. The drugs were continuously administered once a day for 12 weeks and observed for 24 weeks after drug withdrawal. The drug safety profile was assessed concurrently with the observation of the sustained virological response (SVR12) in the two patient groups 12 weeks following the drug cessation. The intention-to-treat concept was used to define as closely as possible a full analysis set, including all randomized cases who received the experimental drug at least once. The safety set was collected from all subjects who received the experimental drug at least once (regardless of whether they participated in the randomization group) in this study. All efficacy endpoints and safety profile data were summarized using descriptive statistics. The primary efficacy endpoint was SVR12. The primary analysis was performed on a full analysis set. The frequency and proportion of cases were calculated in the experimental drug group (antaitasvir phosphate capsules combined with yiqibuvir tablets) that achieved "HCV RNA