ObjectiveTo investigate the effect of Tougu Xiaotong capsules （TGXTC） on the regulation of chondrocyte PANoptosis， delay of chondrocyte degeneration， and improvement of the symptoms in knee osteoarthritis （KOA）. MethodsIn vivo experiments： 50 male C57BL/6 mice were randomly assigned into five groups （n=10 per group）： sham operation group， model group， low-dose TGXTC group （7.2 g·kg^-1）， high-dose TGXTC group （14.4 g·kg^-1）， and diclofenac sodium group （0.05 g·kg^-1）. Except for the sham group， KOA models were established in all other groups using the modified Hulth method. Following successful model induction， the TGXTC groups received daily oral gavage of 7.2 or 14.4 g·kg^-1 for 6 weeks， while the diclofenac sodium group received 0.05 g·kg^-1 solution daily over the same duration. Model evaluation was performed using Lequesne MG score； micro-computed tomography （micro-CT） was used to scan the knee， hematoxylin-eosin （HE） staining and safranin O-fast green staining were used to observe the morphology of cartilage， transmission electron microscopy （TEM） was used to determine ultrastructural changes of PANoptosis. Multiple immunofluorescence （IF） co-localization assays was performed to detect the co-localization of cleaved Caspase-3， receptor-interacting protein 3 （RlPK3）， and the N-terminal domain of gasdermin D （GSDMD-N） in cartilage tissue， while western blot was employed to detect the expression levels of cleaved Caspase-3， RIPK3， and GSDMD-N. In vitro experiments： The knee cartilages of 4-week-old SD rats were isolated， and a chondrocyte in vitro culture system was established through mechanical digestion with 0.2% type Ⅱ collagenase. Second-generation chondrocytes were divided into three groups： the control group， the model group （pretreated with 10 mg·L^-1 lipopolysaccharide （LPS） for 24 h followed by treatment with 1 μmol·L^-1 nigericin for 4 h）， and the TGXTC treatment group （pretreated with 10 mg·L^-1 LPS for 24 h， followed by exposure to 1 μmol·L^-1 nigericin for 4 h and subsequently treated with 100 mg·L^-1 TGXTC for an additional 24 h）. The levels of reactive oxygen species （ROS）， apoptosis， necroptosis， and pyroptosis of chondrocytes were evaluated via fluorescence microscopy following staining with ROS detection， AO/EB and YO-PRO-1/PI staining kits. Transmission electron microscopy was utilized to investigate the ultrastructural changes associated with PANoptosis in cartilage tissue of KOA mice. Inflammatory cytokine levels （IL-1β and IL-18） were measured using ELISA. Western blot was conducted to assess protein expressions related to PANoptosis， including cleaved Caspase-3， cleaved Caspase-8， RIPK3， ZBP1， GSDMD-N， and NLRP3. ResultsCompared with the sham group， the Lequesne MG scores were significantly up-regulated（P<0.01） in the model group， and the pathological changes of cartilage were significantly， with joint spaces narrower， osteophyte formation increased， secere abrasion of cartilage surface. Ultrastructural analysis revealed pronounced chondrocyte apoptosis， necroptosis， and pyroptosis， along with markedly elevated expression of cleaved Caspase-3， RlPK3， and GSDMD-N in cartilage tissue （P<0.01）. In addition， The mean fluorescence intensities of ROS， orange-red fluorescence in AO/EB staining， green fluorescence and red fluorescence in YO-PRO-1/PI staining were increased of chondrocyte in the model group （P<0.01） . The levels of inflammatory factors IL-1β and IL-18 in the supernatant were increased （P<0.01）. The expression of PANoptosis related proteins （cleaved Caspase-3， cleaved Caspase-8， RIPK3， ZBP1， GSDMD-N， and NLRP3） were also significantly upregulated（P<0.05）. Compared to the model group， the TGXTC group demonstrated a significant improvement in various parameters of mice. These included a reduction in the Lequesne MG score， an increase in joint space， a decrease in osteophyte formation， diminished cartilage damage， reduced release of ROS， and alleviation of apoptotic， necroptotic， and pyroptotic processes in chondrocytes. Additionally， mitochondrial swelling and endoplasmic reticulum dilation were also mitigated. The levels of ROS as well as IL-1β and IL-18 were significantly decreased （P<0.05）. Furthermore， the expression levels of proteins associated with PANoptosis in cartilage tissue showed marked reductions （P<0.05）. Similar results were observed in chondrocytes： cleaved Caspase-3， cleaved Caspase-8， RIPK3， ZBP1， GSDMD-N， and NLRP3 exhibited significant decreases as well （P<0.05）. ConclusionTGXTC may mitigate chondrocytes degeneration and alleviate KOA symptoms by reducing oxidative stress and suppressing the activation of PANoptosis pathways.

ObjectiveTo investigate the effect of Tougu Xiaotong capsules （TGXTC） on the regulation of chondrocyte PANoptosis， delay of chondrocyte degeneration， and improvement of the symptoms in knee osteoarthritis （KOA）. MethodsIn vivo experiments： 50 male C57BL/6 mice were randomly assigned into five groups （n=10 per group）： sham operation group， model group， low-dose TGXTC group （7.2 g·kg^-1）， high-dose TGXTC group （14.4 g·kg^-1）， and diclofenac sodium group （0.05 g·kg^-1）. Except for the sham group， KOA models were established in all other groups using the modified Hulth method. Following successful model induction， the TGXTC groups received daily oral gavage of 7.2 or 14.4 g·kg^-1 for 6 weeks， while the diclofenac sodium group received 0.05 g·kg^-1 solution daily over the same duration. Model evaluation was performed using Lequesne MG score； micro-computed tomography （micro-CT） was used to scan the knee， hematoxylin-eosin （HE） staining and safranin O-fast green staining were used to observe the morphology of cartilage， transmission electron microscopy （TEM） was used to determine ultrastructural changes of PANoptosis. Multiple immunofluorescence （IF） co-localization assays was performed to detect the co-localization of cleaved Caspase-3， receptor-interacting protein 3 （RlPK3）， and the N-terminal domain of gasdermin D （GSDMD-N） in cartilage tissue， while western blot was employed to detect the expression levels of cleaved Caspase-3， RIPK3， and GSDMD-N. In vitro experiments： The knee cartilages of 4-week-old SD rats were isolated， and a chondrocyte in vitro culture system was established through mechanical digestion with 0.2% type Ⅱ collagenase. Second-generation chondrocytes were divided into three groups： the control group， the model group （pretreated with 10 mg·L^-1 lipopolysaccharide （LPS） for 24 h followed by treatment with 1 μmol·L^-1 nigericin for 4 h）， and the TGXTC treatment group （pretreated with 10 mg·L^-1 LPS for 24 h， followed by exposure to 1 μmol·L^-1 nigericin for 4 h and subsequently treated with 100 mg·L^-1 TGXTC for an additional 24 h）. The levels of reactive oxygen species （ROS）， apoptosis， necroptosis， and pyroptosis of chondrocytes were evaluated via fluorescence microscopy following staining with ROS detection， AO/EB and YO-PRO-1/PI staining kits. Transmission electron microscopy was utilized to investigate the ultrastructural changes associated with PANoptosis in cartilage tissue of KOA mice. Inflammatory cytokine levels （IL-1β and IL-18） were measured using ELISA. Western blot was conducted to assess protein expressions related to PANoptosis， including cleaved Caspase-3， cleaved Caspase-8， RIPK3， ZBP1， GSDMD-N， and NLRP3. ResultsCompared with the sham group， the Lequesne MG scores were significantly up-regulated（P<0.01） in the model group， and the pathological changes of cartilage were significantly， with joint spaces narrower， osteophyte formation increased， secere abrasion of cartilage surface. Ultrastructural analysis revealed pronounced chondrocyte apoptosis， necroptosis， and pyroptosis， along with markedly elevated expression of cleaved Caspase-3， RlPK3， and GSDMD-N in cartilage tissue （P<0.01）. In addition， The mean fluorescence intensities of ROS， orange-red fluorescence in AO/EB staining， green fluorescence and red fluorescence in YO-PRO-1/PI staining were increased of chondrocyte in the model group （P<0.01） . The levels of inflammatory factors IL-1β and IL-18 in the supernatant were increased （P<0.01）. The expression of PANoptosis related proteins （cleaved Caspase-3， cleaved Caspase-8， RIPK3， ZBP1， GSDMD-N， and NLRP3） were also significantly upregulated（P<0.05）. Compared to the model group， the TGXTC group demonstrated a significant improvement in various parameters of mice. These included a reduction in the Lequesne MG score， an increase in joint space， a decrease in osteophyte formation， diminished cartilage damage， reduced release of ROS， and alleviation of apoptotic， necroptotic， and pyroptotic processes in chondrocytes. Additionally， mitochondrial swelling and endoplasmic reticulum dilation were also mitigated. The levels of ROS as well as IL-1β and IL-18 were significantly decreased （P<0.05）. Furthermore， the expression levels of proteins associated with PANoptosis in cartilage tissue showed marked reductions （P<0.05）. Similar results were observed in chondrocytes： cleaved Caspase-3， cleaved Caspase-8， RIPK3， ZBP1， GSDMD-N， and NLRP3 exhibited significant decreases as well （P<0.05）. ConclusionTGXTC may mitigate chondrocytes degeneration and alleviate KOA symptoms by reducing oxidative stress and suppressing the activation of PANoptosis pathways.

Objective:To observe the changes in serum estradiol (E 2) levels in pregnant women of different gestational weeks and their predictive value for early intrauterine pregnancy outcomes. Methods:A retrospective study was conducted involving 375 pregnant women who were treated at the Affiliated Yangming Hospital of Ningbo University (Yuyao People's Hospital) from September 2021 to September 2023. The clinical data were categorized based on pregnancy outcomes into three groups: a normal pregnancy group ( n = 150), a threatened miscarriage with continued pregnancy group ( n = 150), and a miscarriage group ( n = 75). The serum estradiol (E 2) levels at different gestational weeks were compared among the three groups: 5 to < 6 weeks (35-41 days), 6 to < 7 weeks (42-48 days), and 7 to 8 weeks (49-55 days). The predictive value of serum E 2 levels for early intrauterine pregnancy outcomes across different gestational weeks was analyzed using Receiver Operating Characteristic (ROC) curves. Results:In the normal pregnancy group, the serum E 2 levels at different gestational weeks were as follows: (1 691.87 ± 532.21) pmol/L for 5 to < 6 weeks, (2 376.64 ± 788.36) pmol/L for 6 to < 7 weeks, and (3 576.30 ± 1,190.06) pmol/L for 7 to 8 weeks. These values were significantly higher than those in the threatened miscarriage with continued pregnancy group [(1 409.28 ± 473.49) pmol/L, (1 893.13 ± 563.15) pmol/L, (2 035.79 ± 612.47) pmol/L, t = 5.15, 11.68, 6.60, all P < 0.05] and the miscarriage group [(906.49 ± 338.09) pmol/L, (923.63 ± 365.39) pmol/L, (950.27 ± 378.89) pmol/L, t = 16.19, 15.45, 21.50, all P < 0.05]. The serum E 2 levels at different gestational weeks in the threatened miscarriage with continued pregnancy group were significantly higher than those in the miscarriage group ( t = 7.48, 10.81, 8.89, all P < 0.05). Both the normal pregnancy group and the threatened miscarriage with continued pregnancy group showed an increasing trend in serum E 2 levels with advancing gestational weeks ( t = 6.74, 18.55, 7.58, 9.82, 11.81, 2.24, all P < 0.05). In contrast, the serum E 2 levels in the miscarriage group also increased with advancing gestational weeks, but the differences were not statistically significant ( P > 0.05). The results from the receiver operating characteristic curve analysis indicated that the areas under the curve for predicting early intrauterine pregnancy outcomes based on serum E 2 levels at different gestational weeks were 0.857, 0.810, and 0.839, demonstrating excellent diagnostic efficacy. Conclusions:Dynamic monitoring of serum E 2 levels is beneficial for predicting early intrauterine pregnancy outcomes and providing guidance for clinical diagnosis and treatment.

BACKGROUND:Our previous research found that Tougu Xiaotong Capsules can be used not only for the treatment of osteoarthritis,but also for rheumatoid arthritis and gouty arthritis.However,the specific mechanism of action of"Same Treatment for Different Diseases"is still unclear.OBJECTIVE:To identify the main effects and mechanisms of Tougu Xiaotong Capsules in the treatment of osteoarthritis,rheumatoid arthritis and gouty arthritis with the treating principle of"Same Treatment for Different Diseases"by the methodologies of integrated pharmacology,molecular docking techniques and molecular dynamics simulation.METHODS:The active chemical components of Tougu Xiaotong Capsules and their corresponding targets were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP)and the Swiss Target Prediction database.The disease genes for osteoarthritis,rheumatoid arthritis and gouty arthritis were obtained from the GeneCards and OMIM databases.Cytoscape 3.7.2 software was used to construct a drug-component-disease-target network diagram and a protein-protein interaction network.Gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were conducted using the Daivd database.Molecular docking simulations were performed on the CB-DOCK2 website,and molecular dynamics simulations were carried out using the GROMACS 2020.6 software.RESULTS AND CONCLUSION:(1)A total of 50 active components of Tougu Xiaotong Capsules were screened,with 184 potential targets and 29 intersection targets across the three types of arthritis.(2)The gene ontology enrichment analysis of the intersection targets indicated that the key gene functions of Tougu Xiaotong Capsules in treating the three types of arthritis were found to be cellular response to lipopolysaccharide,inflammatory response,extracellular matrix,protein binding,and zinc ion binding.(3)Kyoto Encyclopedia of Genes and Genomes enrichment analysis identified key pathways as interleukin-17 signaling pathway,tumor necrosis factor signaling pathway,NOD-like receptor and Toll-like receptor signaling pathways.(4)Six core targets[interleukin-6,interleukin-1β,prostaglandin endoperoxide synthase 1,prostaglandin endoperoxide synthase 2,cytochrome P450 1A2(CYP1A2)and C-X-C chemokine ligand 8]were determined based on the protein-protein interaction network.(5)Molecular docking results confirmed that(+)-catechin,β-sitosterol,kaempferol,myricetin,and wallichilide had good structure-activity relationships.Molecular dynamics simulations further confirmed the stable binding of CYP1A2 with wallichilide,corroborating the network pharmacology and molecular docking results.Therefore,Tougu Xiaotong Capsules may regulate the interleukin-17 signaling pathway,tumor necrosis factor signaling pathway,and other signaling pathways by targeting interleukin-1β,prostaglandin endoperoxide synthase 1,prostaglandin endoperoxide synthase 2 and CYP1A2,exert an effect of"Same Treatment for Different Diseases"on osteoarthritis,rheumatoid arthritis and gouty arthritis.

Objective This study aims to discuss and summarize the management system for drugs used in clinical trials,with the objective of elevating the management standards.Methods Considering the situation of diverse departmental needs and the multi-campus structure,the study analyzed and explored the management of drugs for clinical trials to build a corresponding management system,including pharmacy construction,equipment,personnel qualifications,data management,drug reception,storage,distribution,and recycling protocols.The effecttivness of the system was evaluated through comparative analysis of data from 2022 to 2023 at our hospital.Result Improvements in the management of drugs for clinical trials were observed in 2023 across varous aspects.Conclusion Refining the management system of drugs for clinical trials can enhance Good Clinical Practice(GCP)supervision and service,providing an important reference for the management system.

Objective To investigate extended high-frequency hearing in young adults and to analyse its char-acteristics.Methods A total of 230 freshmen(101 males and 129 females,aged 17-19 years old)from the class of 2023 at the Air Force Medical University underwent audiometric tests,including acoustic impedance,conventional frequency and extended high-frequency audiometry,and distortion product otoacoustic emissions(DPOAE).Ac-cording to the results of extended high-frequency audiometry,the students were divided into normal and abnormal groups,and the hearing thresholds at conventional frequencies were compared between the two groups.Results Of the 230 students,47.83％(110/230)showed abnormal extended high-frequency hearing.The hearing thresholds of the right ear were 1 to 3 dB higher than those of the left ear at most frequencies.The hearing thresholds of the ab-normal group were higher than those of the normal group in the conventional frequencies(P＜0.05).The difference in extended high-frequency thresholds between the two groups increased with higher frequency.Conclusion Ex-tended high-frequency hearing loss occurs earlier,and has a higher prevalence in young adults,and right ear hearing is worse than that of left ear.Extended high-frequency audiometry can be used as a predictive tool for detecting con-ventional frequency hearing loss.

Objective To investigate extended high-frequency hearing in young adults and to analyse its char-acteristics.Methods A total of 230 freshmen(101 males and 129 females,aged 17-19 years old)from the class of 2023 at the Air Force Medical University underwent audiometric tests,including acoustic impedance,conventional frequency and extended high-frequency audiometry,and distortion product otoacoustic emissions(DPOAE).Ac-cording to the results of extended high-frequency audiometry,the students were divided into normal and abnormal groups,and the hearing thresholds at conventional frequencies were compared between the two groups.Results Of the 230 students,47.83％(110/230)showed abnormal extended high-frequency hearing.The hearing thresholds of the right ear were 1 to 3 dB higher than those of the left ear at most frequencies.The hearing thresholds of the ab-normal group were higher than those of the normal group in the conventional frequencies(P＜0.05).The difference in extended high-frequency thresholds between the two groups increased with higher frequency.Conclusion Ex-tended high-frequency hearing loss occurs earlier,and has a higher prevalence in young adults,and right ear hearing is worse than that of left ear.Extended high-frequency audiometry can be used as a predictive tool for detecting con-ventional frequency hearing loss.

Objective:To evaluate the efficacy and safety of nebulized inhalation of recombinant human interferon (IFN) α1b injection in the treatment of respiratory syncytial virus (RSV) associated lower respiratory tract infections (pneumonia and bronchiolitis) in children.Methods:A randomized, double-blind, parallel, placebo-controlled add-on design was used.Children with pneumonia or bronchiolitis aged 2 months to 5 years who tested positive for RSV antigen within 72 hours of onset from 30 clinical trial sites including Beijing Children′s Hospital, Capital Medical University between February 2021 and December 2022 were included in this study and randomly divided into 2 groups at a ratio of 1∶1 based on a stratified-block method.Both groups received basic treatments such as cough control, asthma relieving, expectorant treatment, fever reduction, oxygen therapy, etc.The experimental group received additional nebulized inhalation of IFN α1b injection at a dose of 2.0 μg/(kg·time), twice a day.The control group received nebulized inhalation of placebo twice a day.Clinical efficacy was evaluated based on indicators such as the duration of clinical symptoms and signs, and the Kaplan-Meier method was used to calculate the median and 95% CI of the duration of clinical symptoms and signs.The Log-rank test was used to compared data between groups.Safety was assessed through the incidence of adverse reactions and laboratory tests, and the Chi-square test was used to analyze the difference between groups. Results:There were 123 children in the experimental group and 122 children in the control group.The median durations of all the 5 clinical symptoms and signs [including shortness of breath, wheezing, dyspnea (visible retractions), decreased transcutaneous oxygen saturation, and abnormal mental state] in the experimental group after treatment were slightly shortened than those in the control group [2.7 d(95% CI: 1.9-3.0 d)] vs.[2.9 d(95% CI: 2.6-3.6 d), P=0.027].The improvement in dyspnea (retractions) was especially pronounced in the experimental group, with a relief rate of 50.0% (0, 100%) on the first day of administration[compared with 0 (0, 50.0%) in the control group ( Z=2.002, P=0.025)].The median duration of dyspnea in the experimental group was nearly 1 day shorter than that in the control group [1.0 d(95% CI: 0.7-1.7 d) vs.1.8 d(95% CI: 1.0-2.5 d), P=0.046].There were no significant difference in hospital stay [6.0(5.0, 8.0) d vs.6.5(5.0, 8.0) d, Z=0.675, P=0.500], oxygen therapy duration [32.0(14.0, 96.3) h vs.39.0 (24.0, 83.2) h, Z=0.094, P=0.925], the recovery rate from clinical symptoms during treatment [(105/106, 99.1%) vs.(96/101, 95.0%)], and recurrence rate [(0/106, 0) vs.(2/101, 2.0%)] between the 2 groups (all P>0.05).However, the above-mentioned four indicators in the experimental group showed a trend of clinical benefits.The quantitative virus detection results showed that the RSV viral load in both groups decreased after treatment compared to before treatment.After 2 days of treatment, the decline rate of RSV viral load from the baseline was 0.90 lg copies/(mL·d) in the experimental group and 0.25 lg copies/(mL·d)in the control group, with a statistically significant difference ( P<0.05).Furthermore, there was no statistically significant difference in the incidence of adverse reactions between the 2 groups ( P>0.05).Importantly, no drug-related serious adverse reactions occurred in both groups. Conclusions:The nebulized inhalation therapy of IFN α1b demonstrates efficacy and safety in treating pediatric RSV associated lower respiratory tract infections.It particularly offers outstanding clinical therapeutic value for severe children.

Objective:To evaluate the efficacy and safety of nebulized inhalation of recombinant human interferon (IFN) α1b injection in the treatment of respiratory syncytial virus (RSV) associated lower respiratory tract infections (pneumonia and bronchiolitis) in children.Methods:A randomized, double-blind, parallel, placebo-controlled add-on design was used.Children with pneumonia or bronchiolitis aged 2 months to 5 years who tested positive for RSV antigen within 72 hours of onset from 30 clinical trial sites including Beijing Children′s Hospital, Capital Medical University between February 2021 and December 2022 were included in this study and randomly divided into 2 groups at a ratio of 1∶1 based on a stratified-block method.Both groups received basic treatments such as cough control, asthma relieving, expectorant treatment, fever reduction, oxygen therapy, etc.The experimental group received additional nebulized inhalation of IFN α1b injection at a dose of 2.0 μg/(kg·time), twice a day.The control group received nebulized inhalation of placebo twice a day.Clinical efficacy was evaluated based on indicators such as the duration of clinical symptoms and signs, and the Kaplan-Meier method was used to calculate the median and 95% CI of the duration of clinical symptoms and signs.The Log-rank test was used to compared data between groups.Safety was assessed through the incidence of adverse reactions and laboratory tests, and the Chi-square test was used to analyze the difference between groups. Results:There were 123 children in the experimental group and 122 children in the control group.The median durations of all the 5 clinical symptoms and signs [including shortness of breath, wheezing, dyspnea (visible retractions), decreased transcutaneous oxygen saturation, and abnormal mental state] in the experimental group after treatment were slightly shortened than those in the control group [2.7 d(95% CI: 1.9-3.0 d)] vs.[2.9 d(95% CI: 2.6-3.6 d), P=0.027].The improvement in dyspnea (retractions) was especially pronounced in the experimental group, with a relief rate of 50.0% (0, 100%) on the first day of administration[compared with 0 (0, 50.0%) in the control group ( Z=2.002, P=0.025)].The median duration of dyspnea in the experimental group was nearly 1 day shorter than that in the control group [1.0 d(95% CI: 0.7-1.7 d) vs.1.8 d(95% CI: 1.0-2.5 d), P=0.046].There were no significant difference in hospital stay [6.0(5.0, 8.0) d vs.6.5(5.0, 8.0) d, Z=0.675, P=0.500], oxygen therapy duration [32.0(14.0, 96.3) h vs.39.0 (24.0, 83.2) h, Z=0.094, P=0.925], the recovery rate from clinical symptoms during treatment [(105/106, 99.1%) vs.(96/101, 95.0%)], and recurrence rate [(0/106, 0) vs.(2/101, 2.0%)] between the 2 groups (all P>0.05).However, the above-mentioned four indicators in the experimental group showed a trend of clinical benefits.The quantitative virus detection results showed that the RSV viral load in both groups decreased after treatment compared to before treatment.After 2 days of treatment, the decline rate of RSV viral load from the baseline was 0.90 lg copies/(mL·d) in the experimental group and 0.25 lg copies/(mL·d)in the control group, with a statistically significant difference ( P<0.05).Furthermore, there was no statistically significant difference in the incidence of adverse reactions between the 2 groups ( P>0.05).Importantly, no drug-related serious adverse reactions occurred in both groups. Conclusions:The nebulized inhalation therapy of IFN α1b demonstrates efficacy and safety in treating pediatric RSV associated lower respiratory tract infections.It particularly offers outstanding clinical therapeutic value for severe children.

According the Good Clinical Practice(GCP)and programmatic requirements,we analyze the management characteristics and the costs of drugs for clinical trials in different specialties from the drug management;The characteristics of the management of drugs for different specialties was summarize and the differential factors that may affect the management cost was explored,so as to provide theoretical support for the research institutions to utilize the resources in a rational and efficient way.This article provides a guarantee for the drug management with the aim of enhancing the quality and efficiency of clinical trials.