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.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Platycodonis Radix is the dry root of Platycodon grandiflorum of Campanulaceae, which has a variety of pharmacological effects and is a commonly used bulk Chinese medicine. In this study, the chloroplast genome sequences of six P. grandiflorum from different producing areas has been sequenced with Illumina HiSeq X Ten platform. The specific DNA barcodes were screened, and the germplasm resources and genetic diversity were analyzed according to the specific barcodes. The total length of the chloroplast genome of 6 P. grandiflorum samples was 172 260-172 275 bp, and all chloroplast genomes showed a typical circular tetrad structure and encoded 141 genes. The comparative genomics analysis and results of amplification efficiency demonstrated that trnG-UCC and ndhG_ndhF were the potential specific DNA barcodes for identification the germplasm resources of P. grandiflorum. A total of 305 P. grandiflorum samples were collected from 15 production areas in 9 provinces, for which the fragments of trnG-UCC and ndhG_ndhF were amplificated and the sequences were analyzed. The results showed that trnG-UCC and ndhG_ndhF have 5 and 11 mutation sites, respectively, and 5 and 7 haplotypes were identified, respectively. The combined analysis of the two sequences formed 13 haplotypes (named Hap1-Hap13), and Hap4 is the main genotype, followed by Hap1. The unique haplotypes possessed by the three producing areas can be used as DNA molecular tags in this area to distinguish from the germplasm resources of P. grandiflorum from other areas. The haplotype diversity, nucleotide diversity and genetic distance were 0.94, 4.79×10^-3 and 0.000 0-0.020 3, respectively, suggesting that the genetic diversity was abundant and intraspecific kinship was relatively close. This study laid a foundation for the identification of P. grandiflorum, the protection and utilization of germplasm resources, and molecular breeding.

Objective To investigate the impact of emodin(EM)on vascular endothelial cell injury in rats with diabetes macroangiopathy by regulating hypoxia inducible factor-1α(HIF-1α)/vascular endothelial growth factor(VEGF)signaling pathway.Methods SD rats were divided into blank group and modeling group,the rats in the modeling group were fed with high fat and high sugar combined with N-nitro-L-arginine methyl ester to build the diabetes macroangiopathy model,and the blank group was fed with ordinary diet.The vascular endothelial cells successfully isolated from the thoracic aorta of rats in blank group and modeling group were named control group and model group,respectively.The vascular endothelial cells in the modeling group were divided into model group,dimethyloxallyl glycine(DMOG)group(10 μmol·L-1DMOG),combined group(80 mg·L-1EM+10 μmol·L-1 DMOG)and experimental-L,-M,-H groups(20,40,80 mg·L-1 EM).The apoptosis of rat vascular endothelial cells was detected by flow cytometry;Western blot was applied to detect the expression of HIF-1αand VEGF proteins in rat vascular endothelial cells.Results The apoptosis rates of vascular endothelial cells in experimental-M,-H groups,DMOG group,combined group,model group and control group were(10.18±0.36)％,(6.28±0.20)％,(24.96±1.18)％,(12.36±0.49)％,(18.76±0.68)％and(4.59±0.26)％;HIF-1α protein levels were 0.96±0.07,0.78±0.06,2.03±0.12,1.05±0.13,1.58±0.12 and 0.69±0.05;VEGF protein levels were 0.59±0.05,0.23±0.02,0.98±0.06,0.63±0.04,0.86±0.07 and 0.11±0.01.The above indexes in the model group were compared with the control,DMOG,experimental-M and experimental-H groups,and the above indexes in the combined group were compared with the experimental-H group,and the differences were statistically significant(all P＜0.05).Conclusion EM may inhibit HIF-1α/VEGF pathway to improve vascular endothelial cell injury in rats with diabetes macroangiopathy.

Objective To study the antioxidant activity and organ protection of different components of Panax notoginseng polysaccharide(PNPS)in D-galactose-induced oxidative damage aging model mice.Methods KM mice were randomly divided into normal group,model group,vitamin C(VC)group(given 200 mg·kg-1 VC),crude polysaccharide from Panax notoginseng(CPPN)group,neutral polysaccharide from Panax notoginseng(NPPN)group and acidic polysaccharide from Panax notoginseng(APPN-Ⅰ,APPN-Ⅱ,APPN-Ⅲ)group(given 400 mg·kg-1 CPPN,NPPN,APPN-Ⅰ,APPN-Ⅱ,APPN-Ⅲ,respectively).Except for the normal group,oxidative injury aging mouse models were established by intraperitoneal injection of 1 g·kg-1 D-galactose.The mice were sacrificed after continuous administration for 42 days,and serum and liver homogenate were prepared.Malondialdehyde(MDA)was determined by thiobarbituric acid method;superoxide dismutase(SOD)was determined by tetrazole salt method;glutathione peroxidase(GSH-Px)was determined by double antibody sandwich method.Results Serum SOD in the normal group,model group,VC group,CPPN group,NPPN group and APPN-Ⅰ,APPN-Ⅱ,APPN-Ⅲ groups were(15.07±0.69),(12.79±1.51),(15.56±1.01),(13.69±0.96),(14.27±0.64),(14.31±0.99),(14.18±0.79)and(15.85±0.89)U·mL-1;serum GSH-Px were(105.35±4.97),(90.36±4.31),(111.51±7.00),(113.03±8.06),(118.77±5.19),(123.60±8.08),(131.65±3.60)and(149.22±13.32)ng·L-1;serum MDA were(1.72±0.26),(4.16±0.92),(2.26±0.59),(2.82±0.47),(2.46±0.50),(1.98±0.41),(2.39±0.39)and(2.07±0.24)nmol·mL-1;the liver SOD were(234.22±3.84),(205.04±7.28),(234.63±6.37),(214.99±17.66),(234.13±3.63),(234.63±3.44),(233.87±5.63)and(235.42±2.33)U·mgprot-1;liver GSH-Px were(274.27±23.72),(207.00±15.22),(257.68±16.39),(249.79±18.78),(252.62±10.92),(256.25±21.83),(261.20±17.52)and(263.16±17.98)ng·L-1;liver MDA were(35.70±3.52),(49.65±6.32),(36.15±2.48),(39.17±4.29),(37.40±6.19),(35.34±4.06)and(35.90±5.36),(33.31±7.64)nmol·mgprot-1.Compared with the normal group,SOD,GSH-Px in serum and liver of mice in the model group were significantly reduced,and the content of MDA was significantly increased(all P＜0.01).After treatment with different components of Panax notoginseng polysaccharide,the oxidative indicators in mice were significantly improved,among which APPN-Ⅲ have the best antioxidant activity,which could significantly increase the activities of SOD,GSH-Px in serum and liver,and reduce the content of MDA(all P＜0.01).Conclusion Different components of Panax notoginseng polysaccharide have antioxidant activity and organ protection in vivo,among which APPN-Ⅲ has the best antioxidant activity and has a good organ protection effect.

Objective To compare the efficacy and safety of empagliflozin and linagliptin in the treatment of patients with type 2 diabetes mellitus(T2DM)with heart failure(HF).Methods Patients with T2DM and HF were randomly into control group and treatment group.Both groups were treated with individualized anti-HF and metformin-based hypoglycemic therapy.On this basis,the control group was given linagliptin orally(5 mg each time,once a day),while the treatment group was given oral administration of empagliflozin 10 mg every day.Patients in both groups were treated continuously for 6 months.The clinical efficacy and blood glucose indicators[fasting blood glucose(FBG),2 h postprandial blood glucose(2 h PBG),hemoglobin A1c(HbA1c)],cardiac molecular markers[N-terminal pro-brain natriuretic peptide(NT-proBNP),fibroblast growth factor 23(FGF23),copeptin(CPP)]and caridac function indicators[left ventricular end-diastolic diameter(LVEDD),left ventricular ejection fraction(LVEF),left ventricular remodeling index(LVRI)]before and after treatment were compared,and the adverse drug reactions were recorded.Results There were 40 cases in treatment group and 40 cases in control group.After treatment,the total effective rates in treatment group and control group were 97.50％(39 cases/40 cases)and 80.00％(32 cases/40 cases),with no significant difference(P＜0.05).The FBG levels in treatment group and control group were(7.64±1.18)and(7.83±1.24)mmol·L-1;2 h PBG levels were(8.97±1.46)and(9.04±1.35)mmol·L-1;HbA1c levels were(7.58±1.27)％and(7.65±1.42)％,all with no significant difference(all P＞0.05).The NT-proBNP levels in treatment group and control group were(612.53±204.62)and(1 045.24±316.75)pg·mL-1;FGF23 levels were(362.74±62.61)and(493.27±74.64)μg·L-1;CPP levels were(12.58±3.43)and(16.87±4.36)pmol·L-1;LVEDD values were(51.19±2.36)and(53.35±2.24)mm;LVEF values were(52.69±3.38)％and(50.28±3.75)％;LVRI values were(2.62±0.29)and(2.96±0.33)kg·L-1,all with significant difference(all P＜0.05).The incidence rates of adverse reactions in treatment group and control group were 5.00％(2 cases/40 cases)and 10.00％(4 cases/40 cases),with no significant difference(P＞0.05).Conclusion Both empagliflozin and linagliptin can effectively reduce the blood glucose in patients with T2DM complicated with HF.Empagliflozin can better promote the improvement of cardiac function in patients without significantly increase the incidence of adverse drug reactions.