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.

The early response of plant auxin gene family Aux/IAA (auxin/indole-3-acetic acid) and its interaction with auxin response factor (ARF) are important pattern to regulate plant growth and development. This work identified 28 StoIAA and 24 StoARF members based on the whole genome data of the medicinal plant Senna tora L., which were classified into 10 and 8 subfamilies, respectively. Phylogenetic tree and collinearity analysis showed that S. tora has close evolutionary relationship with the IAA and ARF homologous genes of Glycine max, Medicago truncatula, and the segment duplication events dominate the expansion of StoIAA and StoARF. Gene structure analysis showed that the vast majority of StoIAA and StoARF contain characteristic conserved domain. Transcriptome data showed that StoIAAs and StoARFs were expressed in leaves, roots and seeds, some members had tissue specific expression. The StoIAA and StoARF promoter region most contain functional elements related to stress response, growth and development, hormone induction and secondary metabolism. In addition, gene expression analysis showed that many StoIAAs and StoARFs can quickly respond to drought and salt stress and exhibited same expression patterns under both stress condition. The yeast two-hybrid experiment confirmed that StoARF8 and StoARF10 exhibit varying degrees of interaction with multiple StoIAA proteins, respectively. The above results provide a basis for further biological functional analysis of the Aux/IAA and ARF gene family of S. tora.

Human physiological indicators have become an important standard for assessing health in modern society.Traditional detection methods often require a separate laboratory,complex operation process and long detection time,so it is urgent to develop portable,fast and accurate on-site detection technologies for bioanalysis.Point-of-care testing(POCT),which differs from traditional laboratory testing,can realize the rapid in situ detection of biomarkers without the complicated analytical process of the laboratory.Smartphones,which are an essential tool in our daily life,not only have independent operating systems and built-in storage functions,but also have high-definition cameras,which have great application potential in POCT visualization.The combination of various biosensing technologies and smartphones has developed into a new direction in the field of POCT.This review mainly introduced the research progress of smartphone-based visual biosensors in POCT in recent years,including colorimetric sensors,fluorescence sensors,chemiluminescence sensors and electrochemiluminescence sensors.Finally,the problems faced by smart-phone-based visual biosensors in the application of POCT were summarized,and their future development was prospected.

Objective To observe the effects of amyloid-β(Aβ)receptor PirB on mouse astrocyte proliferation and reactive astrogliosis in vitro.Methods Mouse primary astrocytes were cultured,and divided into control group,Aβ group,Aβ+0.2 μmol/L PEP group,Aβ+0.4 μmol/L PEP group,Aβ+Fluspirilene group,Aβ+GFP-LV group,and Aβ+mPirB-LV group.The mouse astrocytes were treated with soluble PirB extracellular peptide PEP or PirB inhibitor Fluspirilene,respectively,to inhibit endogenous PirB receptor,or overexpressed PirB gene via lentivirus transfection and then treated with Aβ1-42 oligomers.The proliferation of astrocytes was observed by RTCA and EdU methods,and the mRNA expression levels of S-100 calcium-binding protein B(S-100β),Vimentin,Nestin and amyloid precursor protein(APP)associated with reactive astrogliosis of astrocytes were observed by real-time PCR,and the expression level of glial fibrillary acid protein(GFAP)was detected by Western-blotting.Results The results of RTCA monitoring showed that normalized cell index(NCI)values of each group decreased sharply after treatment,and then increased gradually and tended to be stable.The results of EdU staining showed that the proliferative activity of astrocytes was significantly enhanced in the Aβ group(P<0.05)compared with control group;Compared with Aβ group,cell proliferation activity in Aβ + 0.2 μmol/L PEP group,Aβ+0.4 μmol/L PEP group and Aβ+Fluspirilene group were significantly decreased(P<0.01 or P<0.001).The results of real-time PCR showed that compared with control group,mRNA expressions of GFAP,S-100β,Vimentin,Nestin,APP and PirB in Aβ group were significantly increased(P<0.05);Compared with Aβ group,mRNA expressions of GFAP,S-100β,Vimentin,Nestin,APP and PirB in Aβ+0.4 μmol/L PEP group were significantly decreased(P<0.01);Compared with Aβ+GFP-LV group,mRNA expressions of GFAP,S-100β,Vimentin,Nestin,APP and PirB in Aβ +mPirB-LV group were significantly increased(P<0.05).The results of Western blotting showed that compared with control group,the expression of GFAP in Aβ group was significantly increased(P<0.05);Compared with Aβ group,the expression of GFAP in Aβ+0.4 μmol/L PEP group was significantly decreased(P<0.05).Conclusions PirB is an upstream molecule which could regulate astrocyte proliferation and reactive astrogliosis,and inhibiting PirB receptor in astrocytes may be a potential treatment for Alzheimer's disease.

ObjectiveA growing body of research suggests a strong link between metabolic imbalance and Alzheimer’s disease (AD). In recent years, the development of metabolomics makes it possible to study the characteristic changes of peripheral metabolism in AD. Serum levels of tryptophan and tyrosine were associated with mild cognitive impairment (MCI) and AD. The purpose of this study is to further characterize tryptophan and tyrosine levels in MCI and AD. MethodsWe stratified 765 participants from the Alzheimer’s Disease Neuroimaging Initiative-1 (ADNI-1) cohort into cognitively normal (CN; n=207), stable mild cognitive impairment (sMCI; n=201), progressive mild cognitive impairment (pMCI; n=171), and dementia due to AD (n=186). Serum tryptophan and tyrosine were analyzed for diagnostic value of MCI and AD. To evaluate the relationships between serum tryptophan and tyrosine and cerebrospinal fluid (CSF) biomarkers, brain structure (magnetic resonance imaging, MRI), cerebral glucose metabolism (¹⁸F-fluorodeoxyglucose-positron emission tomography, FDG-PET), and cognitive declines, through different cognitive subgroups. ResultsSerum tryptophan was decreased in patients with AD, pMCI or sMCI compared with CN. Serum tyrosine was decreased in patients with AD or pMCI compared with CN. Serum tryptophan has diagnostic value for pMCI and AD. Serum tyrosine has diagnostic value for AD. ConclusionSerum tryptophan and tyrosine contribute to the early diagnosis of AD. The detection of tryptophan and tyrosine can contribute to the pathogenesis of AD. Serum tryptophan and tyrosine were not significantly associated with core AD markers, cognitive function, brain structure and brain metabolism, so serum tryptophan and tyrosine may not be good peripheral AD biomarkers.

Objective To study the pharmacokinetic characteristics of lamotrigine tablets in Chinese healthy subjects under fasting and fed conditions,and to evaluate the bioequivalence and safety profiles between the domestic test preparation and the original reference preparation.Methods Twenty-four Chinese healthy male and female subjects were enrolled under fasting and fed conditions,18 male and 6 female subjects under fasting conditions,17 male and 7 female subjects under fed conditions.A random,open,single-dose,two preparations,two sequences and double-crossover design was used.Plasma samples were collected over a 72-hour period after give the test or reference preparations 50 mg under fasting and fed conditions.The concentration of lamotrigine in plasma was detected by liquid chromatography-tandem mass spectrometry,and the main pharmacokinetic parameters were calculated to evaluate the bioequivalence by WinNonLin 8.1 program.Results The main pharmacokinetic parameters of single-dose the tested and reference preparations were as follows:The fasting condition Cmax were(910.93±248.02)and(855.87±214.36)ng·mL-1;tmax were 0.50(0.25,4.00)and 1.00(0.25,3.50)h;t1/2 were(36.1±9.2)and(36.0±8.2)h;AUC0_72h were(27 402.40±4 752.00)and(26 933.90±4 085.80)h·ng·mL-1.The fed condition Cmax were(701.62±120.67)and(718.95±94.81)ng·mL-1;tmax were 4.00(1.00,5.00)and 4.00(0.50,5.00)h;t1/2 were(44.2±12.4)and(44.0±12.0)h;AUC0-72h were(30 253.20±7 018.00)and(30 324.60±6 147.70)h·ng·mL-1.The 90％confidence intervals of the geometric mean ratios of Cmax and AUC0-72 hfor the test preparation and reference preparation were all between 80.00％and 125.00％under fasting and fed conditions.Conclusion Two kinds of lamotrigine tablets are bioequivalent,and have similar safety in Chinese healthy male and female subjects under fasting and fed conditions.

Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannan-binding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP. Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays. Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05). Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.

Objective:To investigate the association between solid fuel use for heating, smoking, and respiratory diseases.Methods:This study is based on the Qingdao project of the China Kadoorie Biobank. After screening, 26 165 individuals were included in the study. We employed Cox proportional hazards regression models, stratified by risk age (in 5-year intervals) and sex while adjusting for confounding variables such as occupation and physical activity level to analyze the association between solid fuel use for heating, smoking, and increased risk of respiratory diseases.Results:Among the 26 165 participants, the average age of those using solid fuel for heating was (52.57±10.31) years, with females constituting 58.04% and former/current smokers accounting for 65.38%. The results indicated that both the solid fuel group and the former/current smoking group had a higher risk of respiratory diseases, with hazard ratios ( HR) (95% CI) of 1.21 (1.04-1.41) and 1.41 (1.16-1.71), respectively. For the duration of solid fuel use, the HR (95% CI) for 20 years or more, it was 1.27 (1.07-1.51). The multiplicative interaction term between solid fuel use and smoking was statistically significant. Conclusions:The use of solid fuel for heating and smoking significantly increases the risk of respiratory diseases, and there may be a multiplicative interaction between solid fuel use and smoking.

AIM To explore the effects of Zishui Qinggan Decoction on the mouse model of depression induced by chronic restraint stress(CRS)via ERK/GSK3β/CREB/BDNF signaling pathway.METHODS Except for those of the blank group,the mice of other groups were induced into depression models by CRS,and divided into the model group,the fluoxetine hydrochloride group(10 mg/kg)and the low,medium and high dose Zishui Qinggan Decoction groups(8.835,17.670 and 35.340 g/kg)for the corresponding drug intervention and simultanous CRS treatment.The mice had their sugar water preference experiment and behavior experiment on the 7th and 14th day after administration;the observation of the hippocampal morphological changes by HE staining,the detection of the superoxide dismutase(SOD)activity and malondialdehyde(MDA)level in serum by kits,the detection of levels of serum 5-hydroxytryptamine(5-HT),tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)by ELISA,the detection of the hippocampal mRNA expressions of BDNF,TNF-α and IL-1β by RT-qPCR method,and the detection of the hippocampal protein expressions of ERK1/2,p-ERK1/2,GSK3β,p-GSK3β,CREB and BDNF by Western blot method 14 days after administration.RESULTS Compared with the model group,after 14 days of administration,both fluoxetine hydrochloride group and medium-dose Zishui Qinggan Decoction group displayed increased preference rate of sugar water(P<0.01),shortened immobility time of tail suspension and forced swimming(P<0.01),improved hippocampal damage of nerve cells,decreased levels of serum MDA,TNF-α and IL-1β(P<0.05,P<0.01),increased SOD activity and 5-HT level(P<0.05,P<0.01),decreased hippocampal mRNA expressions of TNF-α and IL-1β(P<0.01),and decreased expressions of BDNF mRNA and p-ERK1/2,p-GSK3β,CREB and BDNF proteins(P<0.05,P<0.01).CONCLUSION Zishui Qinggan Decoction can improve the depression-like behaviors in mice exposed to CRS,and its mechanism may be related to the regulation of hippocampal ERK/GSK3β/CREB/BDNF signaling pathway.

【Objective】 To explore the feasibility of en-bloc resection of bladder tumors by flexible cystoscope combined with laparoscopic instruments through urethra and to provide reference for the clinical application of this technique. 【Methods】 Self-designed and processed transurethral single-hole PORT and Olympus electronic cystoscope were used as observation mirror; Φ1.8 mm soft grasper, tissue scissors, electric hook, and ultrasonic scalpel were used as instruments; the porcine bladder was used as a model.The PORT was placed through the urethra, and the cystoscope was inserted to observe the inner wall of the bladder and the condition of the mucosa.After the lesion site was identified in the bladder cavity, the soft grasper was inserted to pull the mucosa to be removed, which was then fixed with tension at the target position to maintain a satisfactory feild of view.The surgeon held the cystoscope in the left hand, and operated the laparoscopic instruments into the bladder cavity through the PORT with the right hand.Observing with the cystoscope and lifting and pulling the mucosa with the grasper, the surgeon simulated the cutting and pushing actions to realize the en-bloc resection of the lesioned mucosa. 【Results】 The mucosa at 4 different locations were successfully resected on 2 in vitro porcine bladder models. 【Conclusion】 The in vitro experiments show that the combination of flexible electronic cystoscope and laparoscopic instruments achieves synergistic effects in en-bloc resection of bladder tumor by transurethral single-hole laparoscope without additional iatrogenic bladder injury caused by percutaneous bladder incision.This method is feasible in the treatment of bladder tumors, and has the potential of clinical application after further optimization.