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 explore the molecular epidemiological characteristics of carbapenem-resistant Klebsiella pneumoniae(CRKP),and reveal its mechanism of resistance to ceftazidime/avibactam(CZA).Methods CZA-re-sistant CRKP strains initially isolated from the Affiliated Hospital of Xuzhou Medical University from January 2021 to September 2023 were collected.The carriage of 5 carbapenemase genes(blaKPC,blaNDM,blaOXA,blaVIM,blaIMp)were detected with gene amplification method and colloidal gold method.The relative copy number and expression level of Klebsiella pneumoniae(KP)carbapenemase-producing KP(KPC-KP)was detected with real-time quantita-tive polymerase chain reaction(RT-qPCR),mutation sites of KPC mutation strains were analyzed with whole-ge-nome sequencing,and epidemic characteristics of CRKP and resistance mechanism to CZA were analyzed.Results A total of 73 CZA-resistant CRKP strains were isolated,with 37(50.68％)being KPC and NDM co-producing strains,33(45.21％)NDM-producing alone(23 strains producing NDM-5 and 10 strains producing NDM-1),and 3 KPC-producing alone.KP-2842 strain was identified as ST11-type KPC-33 variant,KP-2127 and KP-2189 strains produced KPC-2.Compared with KP ATCC BAA-1705,the copy number of blaKPC in these strains up-regulated by 1.04-3.86 fold,and the expression increased by 6.66-12.93 fold,respectively.Colloidal gold and PCR methods demonstrated good consistency and the ability to detect the enzyme co-producing and KPC-33 variant.Conclusion In this hospital,the resistance of CRKP to CZA is primarily mediated by the metalloenzyme NDM,with co-produc-tion of NDM and KPC being a characteristic of CRKP.High copy number and expression level of blaKPC-2 also con-tribute to CZA resistance.This study identified the KPC-33 variant for the first time in ST11-type CRKP in Jiangsu Province.

This study was aimed at understanding the trends in,and scope of,severe fever with thrombocytopenia syndrome(SFTS)in Nanjing,analyzing the spatial distribution pattern,detecting high incidence cluster areas and key popula-tions,and scientifically guiding prevention and control strategies and measures.We obtained data on SFTS cases from 2010 to 2023 in Nanjing from the China Disease Control and Prevention Information System,and described the time,popu-lation,and spatial distribution characteristics.We used joinpoint regression to calculate the annual percentage change(APC)in incidence,then used FleXScan spatial clustering scan analysis to explore spatial clustering areas at the street level.A total of 507 SFTS cases were reported from 2010 to 2023 in Nanjing.The APC was 31.8％(95％CI:22.5％-41.9％,P＜0.001),and the reported incidence in 2023 was 1.42/100 000(134 cases).The seasonal indices from May to August were 2.7,2.1,3.0,and 1.3,respectively,accounting for 76.1％of the total cases.The median age was 66(IQR:55,73)years,which gradually increased from 59 years in 2010-2011 to 68 in 2022-2023(P＜0.001);94.1％of cases were in individuals 45 years or older.Farmers,homemakers/unemployed individuals,and retirees accounted for 90.1％.The epidemic area increased from 11 streets in four districts in 2010-2011 to 58 streets in 11 dis-tricts in 2022-2023.Except for 2012-2013,global spatial autocorrelation analysis showed positive Moran's I values(0.224-0.526,P＜0.001),and FlexScan scan indicated that several streets in Lishui District and Jiangning District were the most likely clusters.Four streets in Pukou District were the secondary clusters from 2018 to 2023,and three streets in Luhe District in 2022-2023 were the secondary clusters(all P＜0.05).The reported incidence of SFTS in Nanjing showed a rapid upward trend,with spread of epidemic areas.The spatial distribution pattern was clustered.Strengthened training in diagnosis and treatment technology and detection ability of medical institutions,surveillance in high-incidence areas,tracing of case flow,and health education of tick and disease prevention knowledge are recommended.

Objective: To evaluate the household secondary attack rates of the SARS-CoV-2 Delta variant and the associated factors. Methods: A COVID-19 outbreak caused by the Delta variant occurred in Nanjing in July 2021. A total of 235 cases with current addresses in Nanjing were reported from 171 households. The subjects in this study were selected from household close contact(s) of infected cases. The information on household index cases and their contacts were collected, and the household secondary attack rate (HSAR) and the risk factors were analyzed by the multi-factor logistic regression model. Results: A total of 234 cases of household close contacts and 64 household secondary cases were reported from 103 households, and the HSAR was 27.4% (64/234, 95%CI:22.0% to 33.4%). The proportions of household size for 2 to 3, 4 to 5, and 6 to 9 were 64.1% (66), 26.2% (27) and 9.7% (10), respectively. A total of 35 cases of household cluster outbreaks were reported (35/103, 34.0%). The number of the first case in the household (FCH) was 103 and males accounted for 27.2% (28 cases), with the median age (Q₁, Q₃) of 49 (9, 56). The number of household close contacts was 234 and males accounted for 59.0% (138 cases), with the median age (Q₁, Q₃) of 42 (20, 55) and the median exposure period (Q₁, Q₃) of 3 (1, 3) days. The multi-factor logistic regression model showed that the higher HSAR was observed in the FCH with the features of airport staff (OR=2.913, 95%CI:1.469-5.774), detection from home quarantine screening (OR=6.795, 95%CI:1.761-26.219) and detection from mass screening (OR=4.239, 95%CI:1.098-16.368). Meanwhile, higher HSAR was observed in cases with longer household exposure (OR=1.221, 95%CI:1.040-1.432), non-vaccination (OR=2.963, 95%CI:1.288-6.813) and incomplete vaccinations (OR=2.842, 95%CI:0.925-8.731). Conclusion: The generation interval of the Delta variant is shortened, and the ability of transmission within the household is enhanced. In the outbreak in Nanjing, the associated factors of HSAR are occupation, detection route, vaccination and exposure period.
Male ; Humans ; SARS-CoV-2 ; COVID-19/epidemiology* ; Incidence ; Family Characteristics

Hard capsules of traditional Chinese medicine(TCM) have different degrees of hygroscopicity, which affects the stability and efficacy of drugs. In this paper, 30 kinds of commercially available TCM capsules were used as the research object. The hygroscopicity curves of capsule contents, capsule shells, and capsules were tested respectively, and the first-order kinetic equation was used for fitting. The results show that during the 24 h hygroscopicity process, the capsule shell can reduce the weight gain caused by the hygroscopicity of the contents by 0.80%-53.0% and the hygroscopicity rate of the capsule contents by 1.74%-91.3%, indicating that the capsule shell has a strong delay effect on the hygroscopicity of the contents of the TCM capsules. Seven physical parameters of the contents of 30 kinds of TCM capsules were determined, and 14 prescription process-related parameters were sorted out. A partial least squares model for predicting the hygroscopicity rate of the contents of TCM capsules(with shell) for 24 h was established. It is found that the hygroscopicity rate of the capsule shell is positively correlated with the hygroscopicity of the contents of TCM capsules(with shell), suggesting that the capsule shell with a low hygroscopicity rate is helpful for moisture prevention. In addition, the pre-treatment process route of the preparation and the type of molding raw materials affect the hygroscopicity. A larger proportion of the extract in the capsule content and a smaller proportion of the fine powder of the decoction pieces indicate stronger hygroscopicity of the capsule content. The 24 h hygroscopicity rate of 15% was used as the classification node of hygroscopicity strength, and the hygroscopicity rate constant of 0.58 was used as the classification node of hygroscopicity speed. The classification system of hygroscopicity behaviors of TCM capsules was established: the varieties with strong and fast hygroscopicity accounted for about 6.67%, while those with strong and slow hygroscopicity accounted for about 33.3%; the varieties with weak and fast hygroscopicity accounted for about 26.7%, while those with weak and slow hygroscopicity accounted for about 33.3%. The classification system is helpful to quantify and compare the hygroscopicity behavior of different TCM capsules and provides a reference for the quality improvement, moisture prevention technologies, and material research of TCM capsules.
Medicine, Chinese Traditional ; Wettability ; Capsules ; Powders ; Technology ; Drugs, Chinese Herbal

Objective To evaluate the pharmacokinetics of multiple doses of ampiroxicam tablets in Chinese healthy subjects .Methods A randomized, open study was conducted.Twelve subjects were orally administrated with 27 mg ampiroxicam tablets, once a day for 11 days. The blood samples were collected on the 8th , 9th , and 10th day before ad-ministration.On the 11 th day, the blood and urine samples were collected at different time points after administration , and the concentrations of am-piroxicam in serum and urine were determinated by HPLC method . Results One subject exited on the 7th day.The main pharmacokinetics parameters of 11 subjects after oral doses for 11 days were as follows:Cmax were(8.14 ±2.81) mg? L-1; t1 /2β was (50.10 ±18.10 ) h; tmax was (5.60 ±4.10) h; AUC0 -∞ was (837.05 ±441.47 ) mg? h? L respectively.Urinary recovery rate was (0.55 ±0.51 )% from zero to 192 hours, respectively.Conclusion After multiple dosing, there was a very high trough concentration before dosing because of a very long half -life of ampiroxicam.Blood concentration and pharmacokinetic parameters are individually different, and little drug is excreted by kidney.

The clinical results of the application of pedicled vascularized bone graft (VBG) from Lister's tubercle vs. traditional bone graft (TBG) were evaluated and compared. Thirteen cases of symptomatic scaphoid nonunion were treated between January 2011 and December 2012, including 7 cases subject to VBG and the rest 6 cases to TBG, respectively. Outcomes were assessed by modified Mayo wrist score system. All cases were followed up for an average period of 3.5 months after operation. The results showed that total scores in VBG group were 86.4±9.4 after operation with excellent result in 4 cases, good in 2 and acceptable in one, and those in TBG group were 71.7±9.3 after operation with good result in 2 cases, acceptable in 3 and disappointing in one. Total score of wrist function was significantly improved in VBG group as compared with TBG group (P<0.05). Our study suggests that VBG method is more effective for treating scaphoid nonunion than TBG method.
Adult ; Bone Transplantation ; methods ; Female ; Fractures, Ununited ; surgery ; Hand Strength ; physiology ; Humans ; Male ; Middle Aged ; Pain ; physiopathology ; Range of Motion, Articular ; physiology ; Retrospective Studies ; Scaphoid Bone ; blood supply ; injuries ; surgery ; Surgical Flaps ; blood supply ; Treatment Outcome ; Wrist ; blood supply ; physiopathology ; Young Adult

BACKGROUNDThere are different materials used for anterior cruciate ligament (ACL) reconstruction. It has been reported that both autologous grafts and allografts used in ACL reconstruction can cause bone tunnel enlargement. This study aimed to observe the characteristics of bone tunnel changes and possible causative factors following ACL reconstruction using Ligament Advanced Reinforcement System (LARS) artificial ligament.

METHODSForty-three patients underwent ACL reconstruction using LARS artificial ligament and were followed up for 3 years. X-ray and CT examinations were performed at 1, 3, 6, 12, 24, and 36 months after surgery, to measure the width of tibial and femoral tunnels. Knee function was evaluated according to the Lysholm scoring system. The anterior and posterior stability of the knee was measured using the KT-1000 arthrometer.

RESULTSAccording to the Peyrache grading method, grade 1 femoral bone tunnel enlargement was observed in three cases six months after surgery. No grade 2 or grade 3 bone tunnel enlargement was found. The bone tunnel enlargement in the three cases was close to the articular surface with an average tunnel enlargement of (2.5 ± 0.3) mm. Forty cases were evaluated as grade 0. The average tibial and femoral tunnel enlargements at the last follow-up were (0.8 ± 0.3) and (1.1 ± 0.3) mm, respectively. There was no statistically significant difference in bone tunnel width changes at different time points (P > 0.05). X-ray and CT measurements were consistent.

CONCLUSIONSThere was no marked bone tunnel enlargement immediately following ACL reconstruction using LARS artificial ligament. Such enlargement may, however, result from varying grafting factors involving the LARS artificial ligament or from different fixation methods.

Adult ; Anterior Cruciate Ligament ; diagnostic imaging ; surgery ; Anterior Cruciate Ligament Reconstruction ; methods ; Female ; Humans ; Male ; Middle Aged ; Radiography ; Reconstructive Surgical Procedures ; methods ; Transplantation, Autologous ; Transplantation, Homologous ; Young Adult

BACKGROUNDA new fluroquinolone antibacterial agent, antofloxacin hydrochloride, developed in China, is an 8-NH(2) derivant of levofloxacin. The purpose of the study was to evaluate the pharmacokinetic characteristics of single and multiple oral doses of antofloxacin hydrochloride in Chinese healthy male volunteers.

METHODSAn open-label, non-randomized, single and multiple dose clinical trial was conducted. In single dose study, 12 subjects took 200 mg antofloxacin hydrochloride. In multiple dose study, 12 subjects took antofloxacin hydrochloride 400 mg once on day 1 and 200 mg once daily from day 2 to day 7. HPLC was used to assay the serum and urinary concentrations of antofloxacin.

RESULTSIn single dose study, the maximum concentration of drug in serum (C(max)), the time to reach C(max) (T(max)), and the area under the serum concentration-time curve (AUC (0-∞)) of antofloxacin were (1.89 ± 0.65) mg/L, (1.29 ± 0.26) hours, and (25.24 ± 7.26) mg×h(-1)×L(-1), respectively. Accumulating elimination rate of antoflocaxin from urine within 120 hours was 39.1%. In multiple dose study, blood concentration of antofloxiacin achieved stable state on day 2 after dosing. The minimum concentration drug in serum (C(min)), AUCss, mean concentration of drug in serum (C(av)), and degree of fluctuation (DF) were (0.73 ± 0.18) mg/L, (47.59 ± 7.85) mg×h(-1)×L(-1), (1.98 ± 0.33) mg/L, and 1.74 ± 0.60, respectively. On day 7 after dosing, T(max), C(max), and AUC (0-∞) was (1.14 ± 0.50) hours, (2.52 ± 0.38) mg/L, and (48.77 ± 8.44) mg×h(-1)×L(-1), respectively. Accumulating elimination rate of antofloxaxin from urine within 120 hours after the last dosing was 60.06%.

CONCLUSIONSThe regimen of 400 mg loading dose given on the first treatment day and then 200 mg dose once daily results in satisfactory serum drug concentration.

Administration, Oral ; Adolescent ; Adult ; Anti-Bacterial Agents ; administration & dosage ; blood ; pharmacokinetics ; urine ; Chromatography, High Pressure Liquid ; Humans ; Levofloxacin ; Male ; Ofloxacin ; administration & dosage ; analogs & derivatives ; blood ; pharmacokinetics ; urine ; Young Adult

OBJECTIVETo investigate the expressions of homeobox transcription factor-2 (CDX(2)) and E-cadherin and their relations to the clinicopathological characteristics of gastric carcinoma.

METHODSImmunohistochemistry was performed on 83 human gastric carcinoma specimens and 40 normal gastric mucosa specimens for examining the expressions of CDX(2) and E-cadherin, and the relations of their expression with the tumor differentiation, infiltration and metastasis were analyzed.

RESULTSAccording to the LaurAn classification, the positive expression rate of CDX(2) in intestinal type of gastric carcinoma was 56.86%, and 34.38% in the diffuse type, showing significant difference between the two types (P<0.05). The positivity rate of E-cadherin was also significantly different between the two types (66.67% vs 28.13%, P<0.01). In regard to tumor differentiation, the positivity of CDX(2) and E-cadherin expressions was significantly different between moderately to well differentiated tumors and poorly differentiated ones (P<0.01). The tumors infiltrating mucosal and submucosal layers were significantly different from those infiltrating the muscular and serous membrane layer in the positivity of CDX(2) and E-cadherin expressions (P<0.01), which were also different for the presence of lymph node metastasis (P<0.05). Regression analysis did not reveal significant correlations between CDX(2) and E-cadherin expression in gastric carcinoma (P>0.05).

CONCLUSIONThe abnormal expression of CDX(2) and E-cadherin plays an important role in the development of gastric carcinoma, especially the intestinal type. CDX(2) and E-cadherin may serve as useful markers to predict the prognosis of patients with gastric carcinoma.

Adult ; Aged ; Biomarkers, Tumor ; genetics ; metabolism ; CDX2 Transcription Factor ; Cadherins ; genetics ; metabolism ; Female ; Homeodomain Proteins ; genetics ; metabolism ; Humans ; Male ; Middle Aged ; Stomach Neoplasms ; genetics ; metabolism ; pathology