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 investigate the diagnostic value of contrast-enhanced ultrasound(CEUS)combined with serum Smad ubiquitin regulatory factor 1(SMURF1)detection for thyroid cancer.Methods A total of 144 suspected thyroid cancer patients admitted to Lishui branch of Zhongda Hospital Affiliated to Southeast University from February 2019 to February 2020 were selected as the study subjects.Based on the histopathological results,they were divided into the thyroid cancer group(76 cases)and the benign group(68 cases).All patients underwent contrast-enhanced ultrasound examination and serum SMURF1 level detection;the diagnostic value of contrast-enhanced ultrasound parameters,serum SMURF1 detection alone,and the combination of the two methods for thyroid cancer were analyzed.Results Contrast-enhanced ultrasound parameters peak intensity(PI),mean perfusion intensity(SImean)and maximum perfusion intensity(SImax)in the thyroid cancer group were lower than those in the benign group,and the level of SMURF1 mRNA was higher than that in the benign group(P<0.05).The sensitivity of contrast-enhanced ultrasound parameter SImax in the diagnosis of thyroid cancer was 82.89%,the specificity was 72.06%,the accuracy was 77.78%,and the Kappa value was 0.552.The sensitivity of serum SMURF1 in the diagnosis of thyroid cancer was 65.79%,the specificity was 94.12%,the accuracy was 79.17%,and the Kappa value was 0.589.The sensitivity,specificity,accuracy and Kappa value of SImax combined with serum SMURF1 in the diagnosis of thyroid cancer were 97.37%,85.29%,91.67%and 0.832,respectively,which were higher than those of SImax and SMURF1 alone(P<0.05),the AUC of the combination of the two methods was 0.927,which was significantly higher than that of the two methods alone(Zcombined vs.SImax=3.999,P<0.001;Zcombined vs.SMURF1=3.270,P=0.001).Conclusion Contrast-enhanced ultrasound combined with serum SMURF1 detection can improve the diagnostic efficiency of thyroid cancer,which may avoid the over-diagnosis on the premise of ensuring the effective diagnosis of thyroid cancer patients.

Objective To investigate the value of the human chorionic gonadotropin(hCG)stimulation test in the diagnosis of disorder of sexual development(DSD)in children.Methods A retrospective analysis was conducted on 132 children with DSD.According to the karyotype,they were divided into three groups:46,XX group(n=10),46,XY group(n=87),and sex chromosome abnormality group(n=35).The above groups were compared in terms of sex hormone levels before and after hCG stimulation test,and the morphological manifestation of the impact of testicular tissue on the results of the hCG stimulation test was analyzed.Results There was no significant difference in the multiple increase of testosterone after stimulation among the three groups(P>0.05).In the 46,XY group,the children with 5α-reductase type 2 deficiency had a testosterone-to-dihydrotestosterone ratio higher than that of the 46,XY DSD children with other causes.Morphological analysis showed that DSD children with testicular tissue demonstrated a significantly higher multiple increase in testosterone after stimulation compared to children without testicular tissue(P<0.05).Conclusions The hCG stimulation test has an important value in assessing the presence and function of testicular interstitial cells in children with different types of DSD,and it is recommended to perform the hCG stimulation test for DSD children with unclear gonadal type.[Chinese Journal of Contemporary Pediatrics,2024,26(2):158-163]

Gut microbiome and their metabolites are closely related to human diseases, which influence the development of diseases by interacting with receptors. G protein-coupled receptor (GPCR) is a receptor superfamily that exists on the surface of cell membrane, which is involved in a wide range of human physiological activities. GPCR is currently considered as important drug targets. Traditional Chinese medicines (TCM) are characterized by multi-components, multi-targets, and multi-pathways. More and more studies have demonstrated that TCM can ultimately intervene in diseases by modulating gut microbiome and their metabolites, affecting their interactions with GPCR. This review discusses the status of gut microbiome and human diseases, the interactions of gut microbiome and their metabolites with GPCR, and the status of GPCR drug development. Based on the above contents, a new model of "TCM-gut microbiome panel-GPCR-disease" is proposed. The interactions between active ingredients of TCM, gut microbiome panel, and GPCR and their effects on disease are elucidated through multi-omics techniques. This review will provide new ideas for analyzing the pharmacological mechanism of TCM efficacy and searching for new targets of TCM.

Immunotherapy is an important breakthrough in canc-er treatment.Unfortunately,low drug concentration in tumor sites almost ineffectively initiates immune responses and thereby severely limits immune therapy applications in clinics.Nanoma-terials are well-recognized drug delivery system in cancer thera-py.Nanographene oxide(NGO)have shown immense perti-nence for anti-cancer drug delivery owing to their ultra-high sur-face area,chemical stability,good biocompatibility and excel-lent photosensitivity.In addition,functionalized modifications on the surface of NGO increase tumor targeting and minimize cy-totoxicity.This study focuses on reviewing the literature and up-dates on NGO in drug delivery and discussing the possibilities and challenges of NGO in cancer synergetic therapy.

Objective: To investigate the species, concentration and seasonal trends of main airborne allergenic pollen in 4 districts and 5 counties of Hohhot City. Methods: The Department of allergy, Beijing Shijitan Hospital Affiliated to Capital Medical University conducted a cross-sectional study about monitoring the airborne allergenic pollen from August 1, 2021 to July 31, 2022 by the gravitational method in 4 districts and 5 counties of Hohhot City, which include Yuquan District, Xincheng District, Huimin District, Saihan District, Tuoketuo County, Helingeer County, Tumotezuoqi County, Wuchuan County and Qingshuihe County. Daily pollens were counted and identified by optical microscopy, and the data were analyzed. Results: The airborne allergenic pollen was collected every month all year round in 4 districts and 5 counties of Hohhot city. Through the whole year of the total quantity of pollens ranged from 24 850 to 50 154 grains per 1 000 mm² and two peaks of pollen concentration in air were observed,which happened in spring (from March to May) and in summer and autumn (from July to September). In spring, the main pollens were tree pollens, which principally distributed in Populus pollen (18.29%), Ulmus pollen (8.36%), Pinus pollen (6.20%), Cupressaceae pollen (5.23%), Betulaceae pollen (2.73%), Salix pollen (1.80%) and Quercus pollen (1.16%). In summer and autumn, the main pollens were weed pollens, which mainly included Artemisia pollen (42.73%), Chenopodiaceae pollen or Amaranthaceae pollen (7.46%), Poaceae pollen (2.26%), Humulus pollen or Cannabis pollen (0.60%). Conclusion: There were two peaks of main airborne allergenic pollen in 4 districts and 5 counties of Hohhot City. In the spring peak of pollen, the main airborne pollens were tree pollens. In the summer and autumn peak of pollen, the main airborne pollens were weed pollens. The Artemisia pollen was the most major airborne pollen in this area.
Humans ; Cross-Sectional Studies ; Pollen ; Hospitals

Objective: To investigate the species, concentration and seasonal trends of main airborne allergenic pollen in 4 districts and 5 counties of Hohhot City. Methods: The Department of allergy, Beijing Shijitan Hospital Affiliated to Capital Medical University conducted a cross-sectional study about monitoring the airborne allergenic pollen from August 1, 2021 to July 31, 2022 by the gravitational method in 4 districts and 5 counties of Hohhot City, which include Yuquan District, Xincheng District, Huimin District, Saihan District, Tuoketuo County, Helingeer County, Tumotezuoqi County, Wuchuan County and Qingshuihe County. Daily pollens were counted and identified by optical microscopy, and the data were analyzed. Results: The airborne allergenic pollen was collected every month all year round in 4 districts and 5 counties of Hohhot city. Through the whole year of the total quantity of pollens ranged from 24 850 to 50 154 grains per 1 000 mm² and two peaks of pollen concentration in air were observed,which happened in spring (from March to May) and in summer and autumn (from July to September). In spring, the main pollens were tree pollens, which principally distributed in Populus pollen (18.29%), Ulmus pollen (8.36%), Pinus pollen (6.20%), Cupressaceae pollen (5.23%), Betulaceae pollen (2.73%), Salix pollen (1.80%) and Quercus pollen (1.16%). In summer and autumn, the main pollens were weed pollens, which mainly included Artemisia pollen (42.73%), Chenopodiaceae pollen or Amaranthaceae pollen (7.46%), Poaceae pollen (2.26%), Humulus pollen or Cannabis pollen (0.60%). Conclusion: There were two peaks of main airborne allergenic pollen in 4 districts and 5 counties of Hohhot City. In the spring peak of pollen, the main airborne pollens were tree pollens. In the summer and autumn peak of pollen, the main airborne pollens were weed pollens. The Artemisia pollen was the most major airborne pollen in this area.
Humans ; Cross-Sectional Studies ; Pollen ; Hospitals

COVID-19 has been prevalent for three years. The virulence of SARS-CoV-2 is weaken as it mutates continuously. However, elderly patients, especially those with underlying diseases, are still at high risk of developing severe infections. With the continuous study of the molecular structure and pathogenic mechanism of SARS-CoV-2, antiviral drugs for COVID-19 have been successively marketed, and these anti-SARS-CoV-2 drugs can effectively reduce the severe rate and mortality of elderly patients. This article reviews the mechanism, clinical medication regimens, drug interactions and adverse reactions of five small molecule antiviral drugs currently approved for marketing in China, so as to provide advice for the clinical rational use of anti-SARS-CoV-2 in the elderly.

The canonical transient receptor potential channel(TRPC)proteins form Ca2+-permeable cation channels that are involved in various heart diseases.However,the roles of specific TRPC proteins in myocardial ischemia/reperfusion(I/R)injury remain poorly understood.We observed that TRPC1 and TRPC6 were highly expressed in the area at risk(AAR)in a coronary artery ligation induced I/R model.Trpc1-/-mice exhibited improved cardiac function,lower serum Troponin T and serum creatine kinase level,smaller infarct volume,less fibrotic scars,and fewer apoptotic cells after myocardial-I/R than wild-type or Trpc6-/-mice.Cardiomyocyte-specific knockdown of Trpc1 using adeno-associated virus 9 mitigated myocardial I/R injury.Furthermore,Trpc1 deficiency protected adult mouse ventricular myocytes(AMVMs)and HL-1 cells from death during hypoxia/reoxygenation(H/R)injury.RNA-sequencing-based transcriptome analysis revealed differential expression of genes related to reactive oxygen species(ROS)generation in Trpc1-/-cardiomyocytes.Among these genes,oxoglutarate dehydrogenase-like(Ogdhl)was markedly downregulated.Moreover,Trpc1 deficiency impaired the calcineurin(CaN)/nuclear factor-kappa B(NF-κB)signaling pathway in AMVMs.Suppression of this pathway inhibited Ogdhl upregulation and ROS generation in HL-1 cells under H/R conditions.Chromatin immunoprecipitation assays confirmed NF-κB binding to the Ogdhl promoter.The cardioprotective effect of Trpc1 deficiency was canceled out by overexpression of NF-κB and Ogdhl in cardiomyocytes.In conclusion,our findings reveal that TRPC1 is upregulated in the AAR following myocardial I/R,leading to increased Ca2+influx into associated cardiomyocytes.Subsequently,this upregulates Ogdhl expression through the CaN/NF-κB signaling pathway,ultimately exacerbating ROS production and aggravating myocardial I/R injury.

With the ongoing epidemic of the Coronavirus disease in China and the widespread development of radiotherapy, radiation-induced lung injury has gradually become a clinical problem that has attracted much attention. The pathogenesis of radiation-induced lung injury is complex, involving an imbalance in the polarization state of alveolar macrophages and an upregulation of alveolar epithelial cell apoptosis. Previous studies have shown that vitamin C is an important antioxidant substance, and preventive use of vitamin C can effectively treat acute lung injury. However, whether prophylactic use of vitamin C can effectively prevent or treat lung injury caused by radioactive substances, and its specific molecular mechanism remains to be studied. The purpose of this study is to investigate whether the prophylactic use of vitamin C to treat the alveolar macrophage cell line RAW 264. 7 and human lung epithelial cells BEAS-2B can effectively control the abnormal polarization of macrophages and the abnormal apoptosis of lung epithelial cells. This study found that after 4 weeks and 8 weeks of radioactive X-ray irradiation, the expression of macrophage M1 polarization state markers such as iNOS was significantly up-regulated (P< 0. 05), and preventive use of vitamin C to treat macrophages and lung epithelial cells can alleviate the polarization state disorder of macrophages and the apoptosis of alveolar epithelial cells caused by external radiation exposure, which is manifested in the down-regulation of the expression of Cleaved Caspase3. In addition, the preventive application of vitamin C treatment can inhibit the MAPK signaling pathway activated by external radiation exposure. Further experimental results showed that the inhibition of the MAPK pathway is the key to inhibiting the M1 polarization of macrophages and the apoptosis of lung epithelial cells. In summary, our findings suggest that vitamin C may play a protective role in acute radiation-induced lung injury by inhibiting macrophage M1 polarization/ promoting macrophage M2 polarization and alleviating alveolar epithelial cell apoptosis. This study will help to better understand the process and mechanism of the preventive effect of vitamin C, a common vitamin, on radiation-induced lung injury.