ObjectiveBased on the theory of "spleen governing transportation and transformation"， this study investigates the efficacy of Atractylodis Macrocephalae Rhizoma processed with Aurantii Fructus Immaturus juice（AMR-AFI） in improving slow-transit constipation（STC）， as well as the synergistic regulatory mechanism involving the microbiota-metabolism axis， thereby elucidating the scientific basis of its processing theory. MethodsAnimals were randomly divided into the control group， model group， positive drug（mosapride） group（3 mg·kg^-1）， and low-， medium-， and high-dose groups of AMR-AFI（3.9， 7.8， 15.6 g·kg^-1）. Except for the control group， the remaining five groups were induced with STC using loperamide hydrochloride. Following modeling， interventions were administered. All groups received continuous administration for 15 d， during which fecal samples， colon tissue， and serum were collected. Constipation improvement was assessed by measuring fecal moisture content and small intestinal propulsion rate， histological morphology of colonic tissue was observed via hematoxylin-eosin（HE） staining， and the levels of interleukin（IL）-6， tumor necrosis factor（TNF）-α， and IL-2 in serum were detected using enzyme-linked immunosorbent assay（ELISA）. Furthermore， the microbial community structure in mouse feces was analyzed by 16S rRNA sequencing， while transcriptomic sequencing was employed to screen differentially expressed genes in colonic tissue， followed by gene ontology（GO） and Kyoto Encyclopedia of Genes and Genomes（KEGG） enrichment analyses. Finally， Spearman correlation analysis was conducted to explore the association between differential microbiota and differential genes. ResultsCompared with the control group， the intestinal propulsion rate and fecal moisture content in the model group were significantly decreased（P<0.01）， while serum levels of IL-6， TNF-α， and IL-2 were significantly elevated（P<0.01）. HE staining showed damage and shedding of colonic mucosal epithelial cells， along with a reduction in goblet cells in the model group. In comparison with the model group， all treatment groups improved the pathological state of the colonic mucosa to varying degrees and reduced serum levels of IL-6， TNF-α， and IL-2（P<0.01）. Among these， the high-dose group of AMR-AFI significantly increased the intestinal propulsion rate and fecal moisture content of rats（P<0.05， P<0.01）. Further transcriptomic analysis revealed that a total of 104 differentially expressed genes were identified from comparisons between the model group and the control group， as well as between the model group and the high-dose group of AMR-AFI. These genes were mainly enriched in pathways closely related to STC pathogenesis， such as arachidonic acid metabolism and aldosterone-regulated sodium reabsorption. 16S rRNA sequencing results indicated that AMR-AFI reversed the structural imbalance of the gut microbiota in model mice， increased species richness， downregulated the relative abundance of pro-inflammatory bacteria such as Parasutterella， and enriched beneficial and butyrate-producing bacteria， including Lachnospiraceae_NK4A136_group， Ruminococcaceae， and Lachnospiraceae. Spearman correlation analysis further showed that the beneficial bacteria enriched in the AMR-AFI group were negatively correlated with genes involved in the arachidonic acid metabolic pathway and positively correlated with genes in the aldosterone-regulated sodium reabsorption pathway. In contrast， pro-inflammatory bacteria in the model group exhibited the opposite correlation trends. ConclusionAMR-AFI can effectively exert synergistic therapeutic effects on STC by regulating intestinal microbiota， arachidonic acid-mediated inflammatory metabolism， and aldosterone-regulated water-salt balance pathways.

ObjectiveBased on the theory of "spleen governing transportation and transformation"， this study investigates the efficacy of Atractylodis Macrocephalae Rhizoma processed with Aurantii Fructus Immaturus juice（AMR-AFI） in improving slow-transit constipation（STC）， as well as the synergistic regulatory mechanism involving the microbiota-metabolism axis， thereby elucidating the scientific basis of its processing theory. MethodsAnimals were randomly divided into the control group， model group， positive drug（mosapride） group（3 mg·kg^-1）， and low-， medium-， and high-dose groups of AMR-AFI（3.9， 7.8， 15.6 g·kg^-1）. Except for the control group， the remaining five groups were induced with STC using loperamide hydrochloride. Following modeling， interventions were administered. All groups received continuous administration for 15 d， during which fecal samples， colon tissue， and serum were collected. Constipation improvement was assessed by measuring fecal moisture content and small intestinal propulsion rate， histological morphology of colonic tissue was observed via hematoxylin-eosin（HE） staining， and the levels of interleukin（IL）-6， tumor necrosis factor（TNF）-α， and IL-2 in serum were detected using enzyme-linked immunosorbent assay（ELISA）. Furthermore， the microbial community structure in mouse feces was analyzed by 16S rRNA sequencing， while transcriptomic sequencing was employed to screen differentially expressed genes in colonic tissue， followed by gene ontology（GO） and Kyoto Encyclopedia of Genes and Genomes（KEGG） enrichment analyses. Finally， Spearman correlation analysis was conducted to explore the association between differential microbiota and differential genes. ResultsCompared with the control group， the intestinal propulsion rate and fecal moisture content in the model group were significantly decreased（P<0.01）， while serum levels of IL-6， TNF-α， and IL-2 were significantly elevated（P<0.01）. HE staining showed damage and shedding of colonic mucosal epithelial cells， along with a reduction in goblet cells in the model group. In comparison with the model group， all treatment groups improved the pathological state of the colonic mucosa to varying degrees and reduced serum levels of IL-6， TNF-α， and IL-2（P<0.01）. Among these， the high-dose group of AMR-AFI significantly increased the intestinal propulsion rate and fecal moisture content of rats（P<0.05， P<0.01）. Further transcriptomic analysis revealed that a total of 104 differentially expressed genes were identified from comparisons between the model group and the control group， as well as between the model group and the high-dose group of AMR-AFI. These genes were mainly enriched in pathways closely related to STC pathogenesis， such as arachidonic acid metabolism and aldosterone-regulated sodium reabsorption. 16S rRNA sequencing results indicated that AMR-AFI reversed the structural imbalance of the gut microbiota in model mice， increased species richness， downregulated the relative abundance of pro-inflammatory bacteria such as Parasutterella， and enriched beneficial and butyrate-producing bacteria， including Lachnospiraceae_NK4A136_group， Ruminococcaceae， and Lachnospiraceae. Spearman correlation analysis further showed that the beneficial bacteria enriched in the AMR-AFI group were negatively correlated with genes involved in the arachidonic acid metabolic pathway and positively correlated with genes in the aldosterone-regulated sodium reabsorption pathway. In contrast， pro-inflammatory bacteria in the model group exhibited the opposite correlation trends. ConclusionAMR-AFI can effectively exert synergistic therapeutic effects on STC by regulating intestinal microbiota， arachidonic acid-mediated inflammatory metabolism， and aldosterone-regulated water-salt balance pathways.

Background/Aims: Dysregulated cholesterol metabolism is a hallmark of hepatocellular carcinoma (HCC) that drives tumor initiation and progression. However, clinical targeting of cholesterol metabolism has yielded limited benefits due to stringent feedback in tumor cells. Identifying a central mediator capable of restoring cholesterol homeostasis within the cell’s intrinsically fine-tuned regulatory framework is urgently needed. Methods: We integrated a proteomic dataset from patients with cholesterol-dysregulated HCC into a global cholesterol metabolic regulatory network to identify potential therapeutic targets for disrupted cholesterol homeostasis. The prognostic significance of the candidate targets was further validated in an independent cohort through immunohistochemistry. Functional and mechanistic studies were conducted in vitro using HCC cell lines and in vivo using mouse models. The pharmacological efficacy of the candidate agent was evaluated in both subcutaneous and orthotopic HCC mouse models. Results: ER lipid raft-associated 1 (ERLIN1), a pivotal regulator of cholesterol metabolism reprogramming, was identified as an independent favorable prognostic indicator in HCC. ERLIN1 constrains HCC progression both in vitro and in vivo by stabilizing the INSIG1–SCAP–SREBP2 axis and maintaining the metabolic balance of intracellular cholesterol. Under hypoxia, impaired factor-inhibiting hypoxia-1-dependent hydroxylation of ASB11 at asparagine residues 90 and 92 enhances ASB11-mediated ERLIN1 degradation. Pharmacological targeting of this axis using zoledronic acid (ZoA) attenuated HCC progression by weakening the ASB11–ERLIN1 interaction and restoring cholesterol homeostasis. Conclusions ERLIN1 represents a druggable metabolic vulnerability in cholesterol-dysregulated HCC. Targeting the ASB11–ERLIN1 axis with the clinically approved ZoA reestablishes cholesterol homeostasis and offers a promising therapeutic strategy to overcome the current limitations of cholesterol-targeted HCC therapies.

OBJECTIVE To clarify the current development status of clinical pharmacist training bases and the pharmacist workforce in China， and to provide evidence for standardizing base construction and promoting the high-quality development of hospital pharmacy. METHODS Questionnaires were distributed to all clinical pharmacist training bases for urgently-needed health professionals and clinical pharmacist training bases under the Chinese Hospital Association that had been approved by the end of 2023 to collect data including base profiles and pharmacist staffing conditions. Expert teams carried out field investigations to verify the collected data. Descriptive statistical analyses were conducted on the quantity， type and regional distribution of training bases， and the influencing factors of pharmacist staffing in the bases were analyzed. RESULTS Field surveys were completed covering 297 training bases across 31 provincial-level administrative regions. Among the base hospitals， 87.88% were Grade A tertiary general hospitals， and 65.32% were located in provincial capitals. The eastern region had the largest number of bases （136， accounting for 45.79%）， followed by the western region （79， 26.60%）. Great disparities existed among provinces in terms of base quantity and hospital scale. The median proportion of pharmaceutical technical personnel in base hospitals was 4.05%， and the median number of clinical pharmacists per 100 hospital beds was 0.53. Both indicators reached the highest in the eastern region （0.57， 4.43%） and the lowest in the northeastern region （0.45， 3.01%）. A total of 3 627 full-time clinical pharmacists were employed in all surveyed bases， among whom 83.68% held clinical pharmacist training certificates， 35.43% possessed senior professional titles， and 78.19% had postgraduate or higher educational background. The total annual training capacity of the surveyed bases was 4 291 trainees， with obvious differences in annual training capacity across regions and provinces. Training specialties covered 19 specialized disciplines plus one general discipline， and no province could deliver training for all 20 specialties simultaneously. Multivariate Logistic regression analysis showed that geographic region exerte d a significant impact on the proportion of pharmaceutical technical personnel （≥4%） （ P ＜0.05）， while the approval time of training bases and hospital scale had significant effects on the number of clinical pharmacists per 100 beds （≥0.6） （ P ＜0.05）. CONCLUSIONS China’s clinical pharmacist training system has basically matured and taken initial shape. The distribution of clinical pharmacist training resources is generally consistent with regional population and economic development levels. However， the allocation of pharmaceutical staff and clinical pharmacists has not yet met national standards and clinical service demands.

OBJECTIVE To clarify the current development status of clinical pharmacist training bases and the pharmacist workforce in China， and to provide evidence for standardizing base construction and promoting the high-quality development of hospital pharmacy. METHODS Questionnaires were distributed to all clinical pharmacist training bases for urgently-needed health professionals and clinical pharmacist training bases under the Chinese Hospital Association that had been approved by the end of 2023 to collect data including base profiles and pharmacist staffing conditions. Expert teams carried out field investigations to verify the collected data. Descriptive statistical analyses were conducted on the quantity， type and regional distribution of training bases， and the influencing factors of pharmacist staffing in the bases were analyzed. RESULTS Field surveys were completed covering 297 training bases across 31 provincial-level administrative regions. Among the base hospitals， 87.88% were Grade A tertiary general hospitals， and 65.32% were located in provincial capitals. The eastern region had the largest number of bases （136， accounting for 45.79%）， followed by the western region （79， 26.60%）. Great disparities existed among provinces in terms of base quantity and hospital scale. The median proportion of pharmaceutical technical personnel in base hospitals was 4.05%， and the median number of clinical pharmacists per 100 hospital beds was 0.53. Both indicators reached the highest in the eastern region （0.57， 4.43%） and the lowest in the northeastern region （0.45， 3.01%）. A total of 3 627 full-time clinical pharmacists were employed in all surveyed bases， among whom 83.68% held clinical pharmacist training certificates， 35.43% possessed senior professional titles， and 78.19% had postgraduate or higher educational background. The total annual training capacity of the surveyed bases was 4 291 trainees， with obvious differences in annual training capacity across regions and provinces. Training specialties covered 19 specialized disciplines plus one general discipline， and no province could deliver training for all 20 specialties simultaneously. Multivariate Logistic regression analysis showed that geographic region exerte d a significant impact on the proportion of pharmaceutical technical personnel （≥4%） （ P ＜0.05）， while the approval time of training bases and hospital scale had significant effects on the number of clinical pharmacists per 100 beds （≥0.6） （ P ＜0.05）. CONCLUSIONS China’s clinical pharmacist training system has basically matured and taken initial shape. The distribution of clinical pharmacist training resources is generally consistent with regional population and economic development levels. However， the allocation of pharmaceutical staff and clinical pharmacists has not yet met national standards and clinical service demands.

OBJECTIVE To investigate the current status of quality management in clinical pharmacist training bases in China， and to provide references for the standardized development and improvement of these bases. METHODS A combined approach of questionnaire survey and on-site investigation was adopted， targeting the healthcare highly sought-after talent （clinical pharmacist） training bases in 31 provinces of China as well as the clinical pharmacist training bases affiliated with the Chinese Hospital Association. A training quality management evaluation index system consisting of 25 tertiary indicators was established. Investigations were conducted from two dimensions： structural quality of training and quality management of training processes. Data were statistically analyzed using descriptive statistical methods. RESULTS On-site investigations were completed for 297 clinical pharmacist training bases across the 31 provinces， among which 284 were affiliated with the Chinese Hospital Association and 271 were healthcare highly sought-after talent （clinical pharmacist） training bases. In terms of structural quality， the core indicator compliance rate for hospital-level training systems exceeded 80%， the rate of special fund utilization for designated purposes reached 80.13%， and the overall compliance rate for software and hardware facilities surpassed 88%. A total of 1 348 preceptors were employed across the training bases， among whom those with senior professional titles and full-time specialist clinical pharmacists as lead preceptors accounted for 62.91% and 94.36%， respectively. Regarding process quality， the compliance rate for “establishment of clinical practice teaching groups in accordance with regulations during clinical department rotations” was 85.19%， and 79.80% and 76.09% of the bases were found to implement strict confidentiality in theoretical examinations and meet the required scale of assessment cases， respectively. However， formal documents of corresponding training management regulations were formulated in only 57.91% of the bases， and the completeness and standardization rate of training manual completion was merely 47.47%. In addition， considerable disparities in quality management levels were observed among provinces， with issues in training process quality being particularly prominent. CONCLUSIONS The management system， hardware facilities， and preceptor staffing of clinical pharmacist training bases in China are relatively well-established， yet notable variations in quality management exist among training bases across different provinces.

Objective:To explore the intimal injury of two kinds of hemostatic clips under different clamping forces, and to optimize and verify the calculation formula of minimum occlusion force (MOF), so as to provide theoretical basis for selecting appropriate hemostatic clips to reduce vascular injury.Methods:A total of 96 male SD rats with body weight ranging from 280 to 300 g (Animal Experimental Center of Shanxi Medical University) were randomly assigned to metal hemostatic clip group ( n=48) and disposable hemostatic clip group ( n=48) by random number table method. Each group was further divided into four subgroups with clamping forces of 0.3, 0.6, 0.9 and 1.2 N for abdominal aortic injury experiments. The damage to the vascular intima was observed under a scanning electron microscope. A vascular closure model was established for mathematical analysis to derive the theoretical calculation formula of the arterial blood management factor (MOF). According to blood pressure (BP), blood vessel diameter (D) and hemostatic clamp width (W), the average values of theoretical and actual MOF data were analyzed by paired t test to verify the accuracy of the formula. From January 2021 to December 2022, six patients (with 12 branch arteries) who presented with oral and maxillofacial malignancies at the Department of Oral and Maxillofacial Surgery, Shanxi Medical University School and Hospital of Stomatology, were included to validate the accuracy of the MOF formula. Results:Under electron microscopy, when the clamping force was 0.3 N, the one-time hemostatic clip caused very little damage to the vascular intima (grade 1 injury), with only a few folds being flattened. When the clamping force was 0.6 N, both types of hemostatic clips caused partial peeling of the intima surface (grade 2-3 injury). However, when the clamping force was adjusted to 0.9 and 1.2 N, the damage caused by both types of hemostatic clips was more severe (grade 3-4 injury), with large areas of intima peeling or even disappearance. In some specimens of the metal hemostatic clip group, the damage even reached the muscular layer. Vascular closure model analysis showed that MOF=2×(1/2×π×D×W×BP), the mean diameter of abdominal aorta of 24 SD rats was (1.41±0.07) mm, the blood pressure was (83.29±11.56) mmHg (1 mmHg=0.133 kPa). The theoretical MOF value was (0.096±0.015) N, the actual clamping force (ACF) was (0.095±0.012) N, there was no statistical significance between the two groups ( t=-0.35, P=0.725). In clinical application, the MOF calculation formula was used to select the appropriate hemostatic clip for 12 arteries, successfully blocking the blood flow, verifying the accuracy of the formula. Conclusions:Hemostatic clips can cause damage to the inner membrane of blood vessels, and the greater the clamping force, the more severe the damage. Disposable hemostatic clips have certain advantages in avoiding excessive damage to the inner membrane of blood vessels. The theoretical MOF calculation formula has a certain degree of reliability and can be used as a reference to select the appropriate hemostatic clip with low damage.

Objective:To investigate the prevalence of and risk factors associated with Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and high-risk human papillomavirus (HPV) coinfections among patients with newly diagnosed syphilis at a hospital in Nanjing. Methods:A cross-sectional study was conducted on patients with newly diagnosed syphilis at the STD Clinic, Hospital of Dermatology, Chinese Academy of Medical Sciences in Nanjing, China from May 2023 to April 2024. Urethral, cervical or rectal swabs were collected according to the gender and types of sexual behavior of the patients. Screening tests for CT, NG and HPV infections were then performed by nucleic acid amplification testing. High-risk HPV testing was performed only in female patients. Univariate analysis was carried out to investigate risk factors associated with CT infection. The chi-square test, chi-square test with continuity correction, or Fisher's exact test was chosen based on the sample size and expected values.Results:A total of 111 newly diagnosed syphilis patients with test specimens were collected, including 71 males (64%) and 40 females (36%), and their ages ranged from 16 to 87 years; there were 82 patients with early syphilis and 29 with late latent syphilis; the number of sexual partners in the past 3 months ranged from 0 to 3. Among the 60 male patients with early syphilis, 1 (1.7%) was co-infected with NG, and 12 (20%) with CT; among the 16 men who have sex with men, 7 (43.8%) were co-infected with CT, while 5 (11.4%) of the 44 heterosexual patients were co-infected with CT, showing a significant difference in CT infection rates between the two groups ( χ2 = 5.80, P = 0.016). Among the 22 female patients with early syphilis, 1 (4.5%) was co-infected with NG, and 8 (36.4%) with CT; among the 12 female patients aged < 25 years, 8 (66.7%) were infected with CT, while none of the 7 patients aged 25-44 years or the 3 patients aged ≥ 45 years were infected with CT, showing a significant difference in CT infection rates among the 3 age groups ( P = 0.005) ; among the 16 female patients with 1 sexual partner in the past 3 months, 3 were infected with CT, while 5 were infected with CT in the 6 female patients with 2-3 sexual partners in the past 3 months, with a significant difference in CT infection rates between the two groups ( P = 0.011). Out of the 40 female patients with syphilis, 16 (40%) were co-infected with high-risk HPV; the HPV infection rates did not differ among different age groups (age groups of < 25 years, 25-44 years, ≥ 45 years: 8/14, 2/9, 6/17, respectively; P = 0.265) . Conclusion:The CT infection rate was relatively high in patients with newly diagnosed early syphilis, and a relatively high infection rate of high-risk HPV was observed in female patients with syphilis aged < 25 years.

OBJECTIVE To develop a prediction model for durable clinical benefit （DCB） in patients with advanced esophageal squamous cell carcinoma （ESCC） receiving programmed death-1 （PD-1） inhibitor. METHODS The clinical data of patients with advanced ESCC who received PD-1 inhibitor in Jieyang People’s Hospital were retrospectively collected between January 2020 to December 2023. Predictors were screened by least absolute shrinkage and selection operator （Lasso） regression， and a multivariable Logistic regression model was developed to predict DCB. A nomogram was constructed based on the model. Internal validation of the prediction model was performed by using the Bootstrap method， and the model was evaluated by the receiver operating characteristic （ROC） curve， calibration curve， and decision curve analysis. RESULTS A total of 91 patients with advanced ESCC were included. The results of Lasso regression combined with Logistic regression analysis indicated that the baseline lymphocyte monocyte ratio （LMR） [odds ratio （OR）＝1.97， 95% confidence interval （CI）： 1.15-3.36， P＝0.013]， albumin （ALB） content （OR＝1.35， 95%CI： 1.13-1.60， P＜0.001）， body mass index （BMI） category 1 [normal vs. low： OR＝ 0.28， 95%CI （0.09-0.96）， P＝0.042]， BMI category 2 [overweight-obesity vs. low： OR＝0.08， 95%CI （0.01-0.59）， P＝0.013]， and treatment regimen [monotherapy vs. monotherapy combination therapy： OR＝0.07， 95%CI （0.01-0.50）， P＝0.008] were predictive factors for patients with advanced ESCC to achieve DCB when treated with PD-1 inhibitor. A prediction model was constructed based on the above indicators. Internal validation of the model using the Bootstrap method showed an area under the curve of 0.831 （95%CI： 0.746-0.904）， with specificity of 74.4% and sensitivity of 75.0%. The Hosmer-Lemeshow test yielded χ2＝ 9.930， P＝0.270， and the calibration curve slope was close to 1. The decision curve analysis demonstrated that the model exhibited good clinical utility within a threshold range of 0.1 to 1.0. CONCLUSIONS The prediction model based on baseline LMR， ALB content， BMI， and treatment regimen demonstrates robust predictive performance and clinical utility for assessing therapeutic efficacy of PD-1 inhibitor in the treatment of advanced ESCC.

Objective:To investigate the role and possible mechanism of tripartite motif-containing protein 72 (Trim72) in acute viral myocarditis (AVMC) in mice.Methods:A mouse model of AVMC was established by intraperitoneal injection of Coxsackievirus B3 (CVB3, 2.0 × 10 5 PFU/mouse). Forty mice were randomly divided into the negative control (NC) + phosphate-buffered saline (PBS) group (NC+PBS group), Trim72 overexpression + PBS group (Trim72 + PBS group), NC + CVB3 group, and Trim72 + CVB3 group ( n = 10). Fourteen days before modeling, mice in each group were injected with adeno-associated virus type 9 vector (AAV9) encoding either negative control or Trim72 overexpression (5.0 × 10 11 VG/mouse) via tail vein. Subsequently, PBS or CVB3 was injected intraperitoneally in the PBS and CVB3 groups, respectively. After seven days, the surviving mice were euthanized, and the heart and serum samples were collected. HE and TUNEL staining were used to observe the cardiac pathological changes and cardiomyocyte apoptosis, respectively. The mRNA expression levels of Trim72 and pro-inflammatory cytokines TNF-α, IL-6, and IL-1β in myocardial tissues of each group were detected by RT-qPCR. The protein levels of cTnI, TNF-α, IL-6, and IL-1β in serum were detected by ELISA. The expression levels of Trim72, apoptosis-related proteins (Bax, Bcl-2, Cleaved caspase-3, Caspase-3), TLR4, p-p65, and p65 were detected by Western blot. Results:The protein and mRNA expression levels of Trim72 in myocardial tissues of mice in the NC+CVB3 group were significantly downregulated compared with those in the NC + PBS group ( P<0.05). Compared with the NC + CVB3 group, Trim72 overexpression significantly increased the protein and mRNA expression of Trim72 in myocardial tissues ( P<0.05), ameliorated myocardial inflammatory injury, decreased the apoptotic index of cardiomyocytes ( P<0.05), and reduced the levels of pro-inflammation cytokines TNF-α, IL-6, and IL-1β in the myocardium and serum ( P<0.05). Additionally, Trim72 overexpression also downregulated the protein expression of Bax, Cleaved caspase-3/Caspase-3, TLR4, and p-p65, and upregulated the protein expression of Bcl-2 in myocardial tissues ( P<0.05). There was no significant difference in the indexes of mice between the NC + PBS and Trim72 + PBS groups ( P>0.05). Conclusions:Trim72 overexpression attenuates AVMC in mice by inhibiting myocardial inflammatory injury and apoptotic imbalance, and the mechanism may be related to the negative regulation of the TLR4/NF-κB signaling pathway.