ObjectiveCerebrospinal fluid (CSF) plays a crucial role in maintaining the homeostasis of the central nervous system (CNS). CSF rapidly exchanges with interstitial fluid (ISF) via the glymphatic system within the brain parenchyma. CSF-ISF circulation and its associated mechanisms are often referred to as the brain lymphatic system. This system is connected directly to meningeal lymphatic vessels (mLVs), jointly performing the function of clearing metabolic waste from the CNS. Emerging evidence indicates that this system is closely associated with the onset and progression of neurodegenerative diseases (NDs) such as Alzheimer’s disease (AD). Importantly, abnormal CSF circulation is not only a downstream consequence of AD pathology, but also a risk factor. In AD, the dynamics of CSF flow within the CNS are diminished, immune dysregulation occurs, and this may increase the risk of AD by exacerbating the burden of amyloid β-protein (Aβ). In the mouse model of AD, impaired CSF flow compromises this clearance function, leading to cognitive deficits. Clinically, acupuncture at cognition-related acupoints is commonly used for the prevention and treatment of AD. However, whether its therapeutic effects are mediated through the modulation of CSF dynamics remains unclear. This study aimed to evaluate the impact of acupuncture on CSF flow and investigate its acupoint specificity. MethodsMice were randomly assigned to experimental groups for the different electroacupuncture groups with the following acupoints: Baihui point (GV 20), Ear point, Neiguan point (PC 6), and Tianshu point (ST 25). Wild-type mice on a C57BL/6J background were used as controls. Fluorescent tracer was injected into the cisterna magna to label CSF flow. Fluorescence imaging was employed to assess the distribution of CSF within the brain before and after acupuncture stimulation. ResultsFollowing tracer injection into the cisterna magna, fluorescence signals rapidly reached the cerebellum and medulla—the regions closest to the injection site. Fluorescence intensity was higher in ventral brain regions compared to dorsal regions, likely due to greater vascular density in ventral areas facilitating CSF-ISF exchange. Electroacupuncture at the GV 20 produced the most pronounced enhancement of CSF across the whole brain, while stimulation at the ST 25 primarily augmented flow within subcortical regions. In contrast, electroacupuncture at the Ear point or the PC 6 had no observable effect on CSF in mice. ConclusionElectroacupuncture promotes CSF flow into the brain parenchyma in an acupoint-specific manner, with GV 20 exhibiting the most pronounced enhancement of CSF dynamics. These findings suggest that acupuncture-mediated facilitation of CSF flow may represent a potential therapeutic strategy for preventing or delaying age-related cognitive decline.

ObjectiveThe malaria parasites remodel the host erythrocyte structure by exporting parasite proteins that interact with the membrane skeleton proteins of red blood cells (RBCs), facilitating their intracellular survival and pathogenicity. Skeleton-binding protein 1 (SBP1) is a conserved exported protein across Plasmodium species. In Plasmodium falciparum, SBP1 has been reported to interact with erythrocyte membrane skeleton proteins 4.1R and spectrin, while its contribution to erythrocyte remodeling and parasite virulence in Plasmodium berghei (Pb) remains unclear. This study aims to determine whether PbSBP1 associates with the host cytoskeletal protein 4.1R and to investigate its role in the remodeling of host RBCs and the pathogenicity of Plasmodium berghei. MethodsIn Plasmodium berghei, the relationship between PbSBP1 and the erythrocyte cytoskeletal protein 4.1R was examined using co-immunoprecipitation. A Pbsbp1 gene knockout mutant of Plasmodium berghei (Pbsbp1∆) was generated based on the principle of double crossover homologous recombination. The deformability of erythrocytes infected with Pbsbp1∆ parasites was assessed using microfluidic methods. Microchannels with an array of cylindrical pillars were used to detect modifications in infected RBC deformability. The infected RBCs were squashed between the rows and recovered between the columns and the transit velocity (μm/s) of infected RBCs travelling through the microchannel was recorded. The component of the erythrocyte membrane skeleton junctional complex, tropomodulin (TMOD), was fluorescently labeled, and the cytoskeletal network of infected erythrocytes was imaged using super-resolution stochastic optical reconstruction microscopy (STORM) to analyze ultrastructural changes in the cytoskeleton of wild-type (WT) and Pbsbp1∆-infected erythrocytes. Actin-based junctional complexes were displayed as individual clusters by the labeled TMOD in the STORM images, and the cluster densities and distances between adjacent clusters of infected RBCs were calculated. Additionally, rodent malaria models (BALB/c mice) and experimental cerebral malaria models (C57BL/6 mice) were employed to monitor the growth of Pbsbp1∆ and WT parasites during the intraerythrocytic stage and their capacity to induce cerebral malaria in mice. ResultsPbSBP1 may participate in the remodeling of infected erythrocytes through direct or indirect interaction with the erythrocyte cytoskeletal protein 4.1R. Microfluidic assays revealed that the deformability of erythrocytes infected with Pbsbp1∆ parasites was significantly enhanced compared to those infected with WT parasites. STORM imaging further demonstrated that the ultrastructure of the erythrocyte cytoskeleton in Pbsbp1∆-infected cells was altered relative to that in WT-infected erythrocytes. The distances between nearest neighbors of clusters had a tendency to increase while the cluster densities were decreased in Pbsbp1∆-infected RBCs compared to WT-infected RBCs. Subsequent phenotypic analysis indicated that the growth rate of Pbsbp1∆ parasites during the intraerythrocytic stage was significantly slower than that of WT parasites, and their ability to induce cerebral malaria in mice was also attenuated. These findings suggest that PbSBP1 is involved in the remodeling of the erythrocyte membrane skeleton, likely through its direct or indirect interaction with protein 4.1R, thereby regulating the deformability of infected erythrocytes and influencing the pathogenicity of the blood-stage parasites. ConclusionThis study establishes a role for PbSBP1 in host erythrocyte remodeling and parasite virulence, providing new research strategies for the prevention and treatment of malaria.

ObjectiveTo explore the effects of Yimei Baijiang formula （YMBJF） on colitis-associated colorectal cancer （CAC） and the nuclear factor kappaB （NF-κB） signaling pathway in mice. MethodsSixty male Balb/c mice of 4-6 weeks old were randomized into 6 groups： Normal， model， capecitabine （0.83 g·kg^-1）， and low-， medium-， and high-dose （4.63， 9.25， 18.50 g·kg^-1， respectively） YMBJF. The mouse model of CAC was established by combining azoxymethane （AOM， 10 mg·kg^-1） and dextran sulfate sodium （DSS， 2%）. At the 5^th week after the start of modeling， the capecitabine group and the YMBJF groups were respectively administrated with the corresponding doses of drugs by gavage once a day for a total of 6 weeks. The body weights and general conditions of mice were measured and observed， and the disease activity index （DAI） was scored. The tumors in the colorectal tissue were counted， and the colorectal length was measured. The histological features of the colorectal tissue in each group of mice were observed by hematoxylin-eosin （HE） staining. The levels of inflammatory cytokines including interleukin-6 （IL-6）， interleukin-1β （IL-1β）， and tumor necrosis factor-α （TNF-α） in the serum were determined by enzyme-linked immunosorbent assay （ELISA）. The expression and localization of proliferating cell nuclear antigen-67 （Ki67）， proliferating cell nuclear antigen （PCNA）， and phosphorylated nuclear transcription factor-κB p65 （p-NF-κB p65） proteins were observed by immunohistochemistry （IHC）. The apoptosis of tumor cells was observed by the TUNEL assay. The mRNA levels of IL-6，IL-1β， TNF-α， nuclear transcription factor-κB p65 （NF-κB p65）， NF-κB inhibitor alpha （IκBα）， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） in the colorectal tissue were quantified by Real-time polymerase chain reaction（Real-time PCR）. The protein levels of NF-κB p65， phosphorylated （p）-NF-κB p65， IκBα， p-IκBα， Bcl-2， and Bax in the colorectal tissue were determined by Western blot. ResultsCompared with the model group， each YMBJF group showed decreases in DAI and tumor number （P0.01）， and the medium-dose and high-dose YMBJF groups showed increases in colorectal length （P0.05）. In addition， each YMBJF group showed alleviated colorectal mucosal pathological injury， declined levels of IL-6， IL-1β， and TNF-α in the serum （P0.05）， reduced expression of Ki67 and PCNA （P0.01）， and down-regulated expression of p-NF-κB p65 （P0.05）. The apoptosis in the medium-dose and high-dose YMBJF groups increased （P0.01）. Each YMBJF group and the capecitabine group showed down-regulated mRNA levels of IL-1β， TNF-α， IL-6， NF-κB p65， and Bcl-2 （P0.05） and up-regulated mRNA levels of IκBα and Bax （P0.05）. The mRNA level of IκBα was up-regulated， and that of Bcl-2 was down-regulated （P0.05） in the high-dose YMBJF group. The protein levels of p-IκBα and Bcl-2 were down-regulated （P0.05） in each YMBJF group. The protein levels of IκBα and Bax were up-regulated in the medium-dose and high-dose YMBJF groups （P0.01）， while those of NF-κB p65 and p-NF-κB p65 were down-regulated （P0.05）. ConclusionYMBJF can reduce the number of tumors， reduce the levels of inflammatory factors， promote tumor cell apoptosis， and inhibit tumor cell proliferation by regulating the direct effector molecules of the NF-κB signaling pathway in the mouse model of CRC.

ObjectiveTo explore the effects of Yimei Baijiang formula （YMBJF） on colitis-associated colorectal cancer （CAC） and the nuclear factor kappaB （NF-κB） signaling pathway in mice. MethodsSixty male Balb/c mice of 4-6 weeks old were randomized into 6 groups： Normal， model， capecitabine （0.83 g·kg^-1）， and low-， medium-， and high-dose （4.63， 9.25， 18.50 g·kg^-1， respectively） YMBJF. The mouse model of CAC was established by combining azoxymethane （AOM， 10 mg·kg^-1） and dextran sulfate sodium （DSS， 2%）. At the 5^th week after the start of modeling， the capecitabine group and the YMBJF groups were respectively administrated with the corresponding doses of drugs by gavage once a day for a total of 6 weeks. The body weights and general conditions of mice were measured and observed， and the disease activity index （DAI） was scored. The tumors in the colorectal tissue were counted， and the colorectal length was measured. The histological features of the colorectal tissue in each group of mice were observed by hematoxylin-eosin （HE） staining. The levels of inflammatory cytokines including interleukin-6 （IL-6）， interleukin-1β （IL-1β）， and tumor necrosis factor-α （TNF-α） in the serum were determined by enzyme-linked immunosorbent assay （ELISA）. The expression and localization of proliferating cell nuclear antigen-67 （Ki67）， proliferating cell nuclear antigen （PCNA）， and phosphorylated nuclear transcription factor-κB p65 （p-NF-κB p65） proteins were observed by immunohistochemistry （IHC）. The apoptosis of tumor cells was observed by the TUNEL assay. The mRNA levels of IL-6，IL-1β， TNF-α， nuclear transcription factor-κB p65 （NF-κB p65）， NF-κB inhibitor alpha （IκBα）， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） in the colorectal tissue were quantified by Real-time polymerase chain reaction（Real-time PCR）. The protein levels of NF-κB p65， phosphorylated （p）-NF-κB p65， IκBα， p-IκBα， Bcl-2， and Bax in the colorectal tissue were determined by Western blot. ResultsCompared with the model group， each YMBJF group showed decreases in DAI and tumor number （P0.01）， and the medium-dose and high-dose YMBJF groups showed increases in colorectal length （P0.05）. In addition， each YMBJF group showed alleviated colorectal mucosal pathological injury， declined levels of IL-6， IL-1β， and TNF-α in the serum （P0.05）， reduced expression of Ki67 and PCNA （P0.01）， and down-regulated expression of p-NF-κB p65 （P0.05）. The apoptosis in the medium-dose and high-dose YMBJF groups increased （P0.01）. Each YMBJF group and the capecitabine group showed down-regulated mRNA levels of IL-1β， TNF-α， IL-6， NF-κB p65， and Bcl-2 （P0.05） and up-regulated mRNA levels of IκBα and Bax （P0.05）. The mRNA level of IκBα was up-regulated， and that of Bcl-2 was down-regulated （P0.05） in the high-dose YMBJF group. The protein levels of p-IκBα and Bcl-2 were down-regulated （P0.05） in each YMBJF group. The protein levels of IκBα and Bax were up-regulated in the medium-dose and high-dose YMBJF groups （P0.01）， while those of NF-κB p65 and p-NF-κB p65 were down-regulated （P0.05）. ConclusionYMBJF can reduce the number of tumors， reduce the levels of inflammatory factors， promote tumor cell apoptosis， and inhibit tumor cell proliferation by regulating the direct effector molecules of the NF-κB signaling pathway in the mouse model of CRC.

ObjectiveCerebrospinal fluid (CSF) plays a crucial role in maintaining the homeostasis of the central nervous system (CNS). CSF rapidly exchanges with interstitial fluid (ISF) via the glymphatic system within the brain parenchyma. CSF-ISF circulation and its associated mechanisms are often referred to as the brain lymphatic system. This system is connected directly to meningeal lymphatic vessels (mLVs), jointly performing the function of clearing metabolic waste from the CNS. Emerging evidence indicates that this system is closely associated with the onset and progression of neurodegenerative diseases (NDs) such as Alzheimer’s disease (AD). Importantly, abnormal CSF circulation is not only a downstream consequence of AD pathology, but also a risk factor. In AD, the dynamics of CSF flow within the CNS are diminished, immune dysregulation occurs, and this may increase the risk of AD by exacerbating the burden of amyloid β-protein (Aβ). In the mouse model of AD, impaired CSF flow compromises this clearance function, leading to cognitive deficits. Clinically, acupuncture at cognition-related acupoints is commonly used for the prevention and treatment of AD. However, whether its therapeutic effects are mediated through the modulation of CSF dynamics remains unclear. This study aimed to evaluate the impact of acupuncture on CSF flow and investigate its acupoint specificity. MethodsMice were randomly assigned to experimental groups for the different electroacupuncture groups with the following acupoints: Baihui point (GV 20), Ear point, Neiguan point (PC 6), and Tianshu point (ST 25). Wild-type mice on a C57BL/6J background were used as controls. Fluorescent tracer was injected into the cisterna magna to label CSF flow. Fluorescence imaging was employed to assess the distribution of CSF within the brain before and after acupuncture stimulation. ResultsFollowing tracer injection into the cisterna magna, fluorescence signals rapidly reached the cerebellum and medulla—the regions closest to the injection site. Fluorescence intensity was higher in ventral brain regions compared to dorsal regions, likely due to greater vascular density in ventral areas facilitating CSF-ISF exchange. Electroacupuncture at the GV 20 produced the most pronounced enhancement of CSF across the whole brain, while stimulation at the ST 25 primarily augmented flow within subcortical regions. In contrast, electroacupuncture at the Ear point or the PC 6 had no observable effect on CSF in mice. ConclusionElectroacupuncture promotes CSF flow into the brain parenchyma in an acupoint-specific manner, with GV 20 exhibiting the most pronounced enhancement of CSF dynamics. These findings suggest that acupuncture-mediated facilitation of CSF flow may represent a potential therapeutic strategy for preventing or delaying age-related cognitive decline.

Objective To study the oral health status of officers and soldiers in a certain unit,so as to provide a basis for the formulation and implementation of oral health support plans.Methods A total of 437 officers and soldiers in a certain unit were enrolled to assess their oral health status through questionnaire survey and clinical examination.Results The prevalences of dental caries and periodontal diseases were 87.6%(383/437)and 90.4%(395/437),respectively;the detection rates of impacted third molars,recurrent aphthous stomatitis,other mucosal diseases,and temporomandibular joint disorders were 12.6%(55/437),54.2%(237/437),29.5%(129/437),and 19.2%(84/437),respectively.In terms of oral medical needs,23.3%(102/437)patients did not need treatment,66.1%(289/437)required elective treatment,9.2%(40/437)required early treatment,and 1.4%(6/437)required urgent treatment.Conclusion Officers and soldiers in this study have a variety of oral diseases,with periodontal diseases having the highest prevalence.Supportting plans should be formulated based on the characteristics of the prevalence of oral diseases among them,and regular oral diagnosis and treatment should be carried out to prevent the development and progression of oral diseases.

Objective To summarize the results of different perioperative anticoagulation protocols for elderly patients with atrial fibrillation(AF)undergoing catheter radiofrequency ablation in our center.Methods A total of 197 elderly AF patients undergoing catheter radiofrequency ablation by a single operator in the First and Sixth Medical Centers of Chinese PLA General Hospital from January 2021 to December 2023 were retrospectively recruited,and the results of relevant exami-nations were collected.Based on the use of different direct oral anticoagulants,they were divided into dabigatran(n=125)and rivaroxaban(n=72)groups.During the procedure,the appropriate dose of unfractionated heparin was administered according to the initial activated clotting time(ACT)with a self-made formula.The time and rate of ACT were recorded,and perioperative ad-verse reactions such as bleeding and thrombosis were observed.Results There were no statistical differences between the two groups in baseline data,including age,gender,BMI,medical history,CHA2DS2-VASc score,HAS-BLED score,and left atrial anteroposterior diameter(P＞0.05).The baseline ACT value was obviously shorter(149.73+23.52 s vs 157.91±24.58 s,P=0.032),the initial heparin dose was significantly higher(0.71±0.12 mg/kg vs 0.65±0.13 mg/kg,P=0.031),and the rate of ACT reaching the target within 15 min was notably lower(60％vs 74％,P＜0.05)in the dabigatran group than the rivaroxaban group.But no significant difference was observed in the rate of ACT reaching the target in 45 min after additional heparin administration according to the formula(86％vs 88％,P＞0.05).The dabigatran group used higher dose of heparin during the procedure than the rivaroxaban group(0.99±0.30 mg/kg vs 0.85±0.31 mg/kg,P=0.009).Peri-cardial effusion was observed in one patient of the rivaroxaban group,and hematoma at the site of femoral vein puncture was seen in one patients of the dabigatran group in 1 d after procedure,which was treated surgically.No other severe complications occurred.Conclusion For elderly pa-tients with AF undergoing catheter ablation therapy,continuous perioperative anticoagulation and individualized application of unfractionated heparin based on initial ACT value can rapidly achieve ACT targets and improve anticoagulation efficacy.

Aim To investigate the effect and mechanism of angiotensin Ⅱ(Ang Ⅱ)on ferroptosis in white adi-pocytes.Methods The 3T3-L1 preadipocytes were differentiated into white adipocytes by inducer stimulation.The experiment was divided into control group,Ang Ⅱ group,Ang Ⅱ+Fer-1(ferroptosis inhibitor)group and Ang Ⅱ+PFT-α(p53 inhibitor)group.Ang Ⅱ was used to treat cells.RT-qPCR and Western blot were used to detect the expression levels of ferroptosis factors and adipokines.JC-1 kit was used to detect mitochondrial membrane potential(MMP)level.Iron ion kit was used to detect intracellular iron content.Glutathione(GSH)kit was used to detect GSH content.Fer-1 and Ang Ⅱ were added to treat cells to detect the the changes of ferroptosis level.The expression of p53 and spermidine/spermine N1-acetyltransferase 1(SAT1)protein was detected.Subsequently,PFT-α and Ang Ⅱ were added to co-treat cells to detect the changes of p53 and SAT1 protein expression,and to observe the effect of inhibiting p53 expression on the expression levels of ferroptosis factors and adipokines.Results 3T3-L1 cells were successfully differentiated into white adipocytes by stimulator-induced differentiation.Ang Ⅱ induced ferroptosis in white adipocytes.RT-qPCR results showed that compared with control group,the mRNA expression of anti-ferroptosis factor glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11)and iron regulatory protein 1(IRP-1)was down-regulated in Ang Ⅱ group,and the mRNA expression of pro-ferroptosis factor acyl-CoA synthetase of long-chain family member 4(ACSL4)was up-regulated.Western blot results showed that compared with control group,the protein expression of SLC7A11 and GPX4 was down-regulated in Ang Ⅱ group,and the protein expression of ACSL4 was up-regulated.Ang Ⅱ treatment increased the content of intracellular iron ions and decreased the levels of GSH and MMP.Compared with Ang Ⅱ group,the mRNA expression of IRP-1 and SLC7A11 was up-regulated in Ang Ⅱ+Fer-1 group.Ang Ⅱ induced changes in the expression profile of adipokines in white adipocytes.Western blot results showed that compared with control group,the protein ex-pression of pro-inflammatory adipokine leptin(LEP),resistin(RETN),interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)was up-regulated in Ang Ⅱ group,and the protein expression of anti-inflammatory adipokine adiponectin(AD-PN)and omentin 1(ITLN1)was down-regulated.In addition,Ang Ⅱ increased the protein expression of p53 and SAT1.Inhibition of p53 expression can improve the level of ferroptosis and adipokine expression in white adipocytes trea-ted with Ang Ⅱ.Western blot results showed that compared with Ang Ⅱ group,the protein expression of p53 and SAT1 was down-regulated in Ang Ⅱ+PFT-α group,the protein expression of SLC7A11 and GPX4 was up-regulated,and the protein expression of ACSL4 was down-regulated.The protein expression of ADPN was up-regulated in Ang Ⅱ+PFT-αgroup,and the protein expression of TNF-α,LEP and RETN was down-regulated.Conclusion Ang Ⅱ induces fer-roptosis in white adipocytes through activating the p53/SAT1 signaling pathway.

Objective To summarize the results of different perioperative anticoagulation protocols for elderly patients with atrial fibrillation(AF)undergoing catheter radiofrequency ablation in our center.Methods A total of 197 elderly AF patients undergoing catheter radiofrequency ablation by a single operator in the First and Sixth Medical Centers of Chinese PLA General Hospital from January 2021 to December 2023 were retrospectively recruited,and the results of relevant exami-nations were collected.Based on the use of different direct oral anticoagulants,they were divided into dabigatran(n=125)and rivaroxaban(n=72)groups.During the procedure,the appropriate dose of unfractionated heparin was administered according to the initial activated clotting time(ACT)with a self-made formula.The time and rate of ACT were recorded,and perioperative ad-verse reactions such as bleeding and thrombosis were observed.Results There were no statistical differences between the two groups in baseline data,including age,gender,BMI,medical history,CHA2DS2-VASc score,HAS-BLED score,and left atrial anteroposterior diameter(P＞0.05).The baseline ACT value was obviously shorter(149.73+23.52 s vs 157.91±24.58 s,P=0.032),the initial heparin dose was significantly higher(0.71±0.12 mg/kg vs 0.65±0.13 mg/kg,P=0.031),and the rate of ACT reaching the target within 15 min was notably lower(60％vs 74％,P＜0.05)in the dabigatran group than the rivaroxaban group.But no significant difference was observed in the rate of ACT reaching the target in 45 min after additional heparin administration according to the formula(86％vs 88％,P＞0.05).The dabigatran group used higher dose of heparin during the procedure than the rivaroxaban group(0.99±0.30 mg/kg vs 0.85±0.31 mg/kg,P=0.009).Peri-cardial effusion was observed in one patient of the rivaroxaban group,and hematoma at the site of femoral vein puncture was seen in one patients of the dabigatran group in 1 d after procedure,which was treated surgically.No other severe complications occurred.Conclusion For elderly pa-tients with AF undergoing catheter ablation therapy,continuous perioperative anticoagulation and individualized application of unfractionated heparin based on initial ACT value can rapidly achieve ACT targets and improve anticoagulation efficacy.

Objective:To examine the manifestations and causes of administrative burden among primary healthcare professionals,and to explore its impact on job burnout through the mediating role of role conflict,providing theoretical and empirical support for governance-level burden-reduction strategies.Methods:An exploratory sequential mixed-methods design was employed,focusing on primary healthcare professionals in Shandong Province.In the first phase,in-depth interviews were conducted with 175 participants;in the second phase,a questionnaire survey of 1,096 participants and follow-up interviews with 107 participants were carried out.Results:The proportions of respondents who reported"heavy"or"very heavy"burdens were 62.7%for inspection,54.8%for documentation,51.8%for reporting,and 24.4%for meetings.Structural equation modeling showed that administrative burden had a direct effect on job burnout(0.150)and an indirect effect through role conflict(0.093).Qualitative findings further indicated that administrative burden largely stemmed from public health traceability requirements and medical insurance policies,and operated through both resource-based and value-based conflicts.Conclusions:Primary healthcare professionals face considerable administrative burdens,which may heighten job burnout through role conflict.Governance reforms should optimize inspection and assessment,streamline data reporting,refine record-keeping,and promote collaborative governance to break the chain of institutional pressure leading to burnout.