Objective:To investigate the changes in sympathetic nerve activity after lower limb immobilization and the role of sympathetic nerve in regulating disuse atrophy of skeletal muscles.Methods:The experiment was divided into the following 3 parts: ① Twelve 8-week-old male C57 mice were randomly divided into a blank control group and a hind limb fixation group ( n=6). The blank control group received no intervention while the hind limb fixation group received splint fixation of the hind limbs for 2 weeks before the musculoskeletal multi-dimensional characterization was completed at the behavioral, pathological and molecular levels. ② Thirty-six 8-week-old male C57 mice were selected and randomly divided into a control group and 5 hind limb fixation groups (for 1, 3, 5, 7 and 14 days) ( n=6). The control group was fed normally until 14 days without any intervention while the 5 hind limb fixation groups were sampled after fixation for 1, 3, 5, 7 and 14 days, respectively. The level of norepinephrine in the serum and the expression level of tyrosine hydroxylase (TH), a marker of sympathetic nerve activity in the paraventricular nucleus of hypothalamus (PVN), were detected to observe the plasticity of sympathetic nerve activity. ③ Eighteen 8-week-old male C57 mice were selected and randomly divided into a blank control group, a hind limb fixation group and a hind limb fixation plus medication group ( n=6). The blank control group received no intervention while the 2 fixation groups were injected with phosphate buffer (PBS) and propranolol hydrochloride solution for 2 consecutive weeks, respectively. The parameters related to the skeletal muscles were compared between the 3 groups. Results:① Compared with the control group, the mass and function of skeletal muscles in the hind limb fixation group were statistically significantly decreased ( P<0.05). ② The levels of serum norepinephrine [(3.27±1.03) ng/mL, (9.21±1.05) ng/mL, (6.36±0.88) ng/mL, (3.84±1.00) ng/mL, and (3.91±0.75) ng/mL] and the PVN TH levels (42.00%±5.38%, 61.67%±5.57%, 55.82%±3.11%, 50.90%±2.53%, and 39.17%±9.07%) in the 5 hind limb fixation groups (for 1, 3, 5, 7 and 14 days) were significantly higher than those in the control group [(1.81±0.72)] ng/mL and 23.33%±5.50%] ( P<0.05). ③ The wet weight of the gastrocnemius muscle [(93.50±4.32) mg] and the cross-section area of the tibial anterior muscle [(1,180.00±95.09) μm 2] in the hind limb fixation plus medication group were increased significantly compared with those in the hind limb fixation group [(80.83±9.99) mg and (907.80±121.00) μm 2] ( P<0.05). Conclusions:Overactivation of the sympathetic nervous system occurs in the mice model of skeletal muscle disuse atrophy after hind limb fixation. Inhibition of sympathetic nerve activity may reduce the severity of skeletal muscle atrophy at the lower limbs.

Objective:To investigate the changes in sympathetic nerve activity after lower limb immobilization and the role of sympathetic nerve in regulating disuse atrophy of skeletal muscles.Methods:The experiment was divided into the following 3 parts: ① Twelve 8-week-old male C57 mice were randomly divided into a blank control group and a hind limb fixation group ( n=6). The blank control group received no intervention while the hind limb fixation group received splint fixation of the hind limbs for 2 weeks before the musculoskeletal multi-dimensional characterization was completed at the behavioral, pathological and molecular levels. ② Thirty-six 8-week-old male C57 mice were selected and randomly divided into a control group and 5 hind limb fixation groups (for 1, 3, 5, 7 and 14 days) ( n=6). The control group was fed normally until 14 days without any intervention while the 5 hind limb fixation groups were sampled after fixation for 1, 3, 5, 7 and 14 days, respectively. The level of norepinephrine in the serum and the expression level of tyrosine hydroxylase (TH), a marker of sympathetic nerve activity in the paraventricular nucleus of hypothalamus (PVN), were detected to observe the plasticity of sympathetic nerve activity. ③ Eighteen 8-week-old male C57 mice were selected and randomly divided into a blank control group, a hind limb fixation group and a hind limb fixation plus medication group ( n=6). The blank control group received no intervention while the 2 fixation groups were injected with phosphate buffer (PBS) and propranolol hydrochloride solution for 2 consecutive weeks, respectively. The parameters related to the skeletal muscles were compared between the 3 groups. Results:① Compared with the control group, the mass and function of skeletal muscles in the hind limb fixation group were statistically significantly decreased ( P<0.05). ② The levels of serum norepinephrine [(3.27±1.03) ng/mL, (9.21±1.05) ng/mL, (6.36±0.88) ng/mL, (3.84±1.00) ng/mL, and (3.91±0.75) ng/mL] and the PVN TH levels (42.00%±5.38%, 61.67%±5.57%, 55.82%±3.11%, 50.90%±2.53%, and 39.17%±9.07%) in the 5 hind limb fixation groups (for 1, 3, 5, 7 and 14 days) were significantly higher than those in the control group [(1.81±0.72)] ng/mL and 23.33%±5.50%] ( P<0.05). ③ The wet weight of the gastrocnemius muscle [(93.50±4.32) mg] and the cross-section area of the tibial anterior muscle [(1,180.00±95.09) μm 2] in the hind limb fixation plus medication group were increased significantly compared with those in the hind limb fixation group [(80.83±9.99) mg and (907.80±121.00) μm 2] ( P<0.05). Conclusions:Overactivation of the sympathetic nervous system occurs in the mice model of skeletal muscle disuse atrophy after hind limb fixation. Inhibition of sympathetic nerve activity may reduce the severity of skeletal muscle atrophy at the lower limbs.

Objective:To study the effects of progesterone on the morphology, proliferation, and secretion of cytokines of human decidual stromal cells (DSCs) in late pregnancy, and to explore the mechanism of progesterone in preventing spontaneous preterm birth.Methods:Human decidual stromal cells in late pregnancy were cultured and treated with different concentrations of progesterone (in the experimental groups, 10 -6 mol/L, 10 -5 mol/L and 10 -4 mol/L progesterone was added to the culture medium respectively, and no progesterone was added to the culture medium of control group). The morphology of DSCs was observed under the microscope, the cell length/width ratio was measured, the proliferation was detected by methyl thiazolyl tetrazolium (MTT) method, and the expressions of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA were detected by RT-qPCR. Results:The length/width ratios of DSCs in progesterone 10 -4 mol/L (5.87±0.19) and 10 -5 mol/L (5.98±0.27) groups were lower than that in control group (6.42±0.19), the differences were statistically significant ( P<0.001, P=0.002). The length/width ratio in the 10 -4 mol/L group was lower than that in the 10 -6 mol/L group (6.28±0.32, P=0.005). The proliferation of DSCs in the 10 -5 mol/L (0.70±0.04) and 10 -4 mol/L (0.78±0.04) groups was higher than that in control group (0.59±0.05; P=0.027, P=0.002), and proliferation of DSCs in 10 -4 mol/L group was higher than that in 10 -6 mol/L group (0.61±0.01, P=0.004). The expression of TNF-α mRNA in each progesterone group was lower than that in control group (all P<0.001) and the expression of TNF-α mRNA in the 10 -5 mol/L and 10 -4 mol/L groups was lower than that in the 10 -6 mol/L group (all P<0.001) . The expressions of IL-6 mRNA decreased gradually in control group, 10 -6 mol/L, 10 -5 mol/L and 10 -4 mol/L groups, the differences were statistically significant (all P<0.001). Conclusion:Progesterone can make the decidual stromal cells wider, promote proliferation, and decrease the expressions of TNF-α and IL-6 mRNA, which may play an important role in the mechanism of progesterone preventing spontaneous preterm birth.

Objective:To study the effects of progesterone on the morphology, proliferation, and secretion of cytokines of human decidual stromal cells (DSCs) in late pregnancy, and to explore the mechanism of progesterone in preventing spontaneous preterm birth.Methods:Human decidual stromal cells in late pregnancy were cultured and treated with different concentrations of progesterone (in the experimental groups, 10 -6 mol/L, 10 -5 mol/L and 10 -4 mol/L progesterone was added to the culture medium respectively, and no progesterone was added to the culture medium of control group). The morphology of DSCs was observed under the microscope, the cell length/width ratio was measured, the proliferation was detected by methyl thiazolyl tetrazolium (MTT) method, and the expressions of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA were detected by RT-qPCR. Results:The length/width ratios of DSCs in progesterone 10 -4 mol/L (5.87±0.19) and 10 -5 mol/L (5.98±0.27) groups were lower than that in control group (6.42±0.19), the differences were statistically significant ( P<0.001, P=0.002). The length/width ratio in the 10 -4 mol/L group was lower than that in the 10 -6 mol/L group (6.28±0.32, P=0.005). The proliferation of DSCs in the 10 -5 mol/L (0.70±0.04) and 10 -4 mol/L (0.78±0.04) groups was higher than that in control group (0.59±0.05; P=0.027, P=0.002), and proliferation of DSCs in 10 -4 mol/L group was higher than that in 10 -6 mol/L group (0.61±0.01, P=0.004). The expression of TNF-α mRNA in each progesterone group was lower than that in control group (all P<0.001) and the expression of TNF-α mRNA in the 10 -5 mol/L and 10 -4 mol/L groups was lower than that in the 10 -6 mol/L group (all P<0.001) . The expressions of IL-6 mRNA decreased gradually in control group, 10 -6 mol/L, 10 -5 mol/L and 10 -4 mol/L groups, the differences were statistically significant (all P<0.001). Conclusion:Progesterone can make the decidual stromal cells wider, promote proliferation, and decrease the expressions of TNF-α and IL-6 mRNA, which may play an important role in the mechanism of progesterone preventing spontaneous preterm birth.

Objective: To analyze the characteristics of trigeminal event-related potentials (tERPs) in different kinds of olfactory disorders (OD), and to evaluate the importance of tERPs for the patients with olfactory dysfunction. Methods: Clinical data of 314 patients with olfactory dysfunction from the Smell and Taste Clinics in Beijing Anzhen Hospital from 2015 to 2021 were retrospectively reviewed, including 158 males and 156 females, aging from 6 to 78 years. The control group consisted of healthy people from medical examination center, who were gender and age matched. The clinical characteristics of OD were analyzed using Sniffin' Sticks test, olfactory event-related potentials (oERPs), tERPs and acoustic rhinometry test. SPSS 17.0 software was used to compare the difference of tERPs between the two groups, and to analyze the related factors affecting trigeminal function. Results: The ratio of tERPs presence was different in OD caused by different reasons: head traumatic OD (54.9%), post-virus infection OD (63.6%), sinonasal inflammatory OD (68.4%) and OD due to other causes (56.9%). Compared with controls, tERPs signals in OD patients showed a significant lower amplitude in the N₁ wave (all P<0.001), and lower amplitude in the P₂ wave in most OD patients (head trauma t=-4.11, P<0.001; sinonasal inflammation t=-2.04, P=0.046; others t=-2.40, P=0.020) except in OD by post-virus infection (t=-1.98, P=0.052). tERPs signals in OD patients by sinonasal inflammation showed longer latency in the N₁ wave (t=2.15, P=0.036), but this difference was not observed in other OD patients (all P>0.05). tERPs signals were significantly correlated with the Sniffin' Sticks score, deficiency of oERPs and nasal minimum cross-sectional area (all P<0.05). Conclusions: OD patients show neurophysiologic deficits in trigeminal function. The absence of tERPs or lower amplitude in N₁ waves are the important characteristics of patients with OD.
Evoked Potentials/physiology* ; Female ; Humans ; Inflammation ; Male ; Olfaction Disorders/etiology* ; Retrospective Studies ; Smell/physiology* ; Virus Diseases/complications*

Objective:To explore the relationship between pathogens in the olfactory cleft area and olfactory disorders in patients with upper respiratory inflammation (URI) during the prevention and control of 2019 novel coronavirus disease (COVID-19).Methods:A total of 234 URI patients including acute upper respiratory infection, chronic rhinosinusitis (CRS), allergic rhinitis (AR) were continuously selected from September 2020 to March 2021 in Beijing Anzhen Hospital and 98 healthy adults were enrolled as controls. The secretions from the olfactory cleft of all subjects were collected with nasal swabs under nasal endoscopy. Multiple real-time fluorescent quantitative polymerase chain reaction detection method was used to detect nucleic acids of 33 types of respiratory pathogenic microorganism. Sniffin′ Sticks olfactory test was performed on all patients with URI. URI patients with olfactory dysfunction were followed up for 9 (8, 10) months ( M ( Q1, Q3)). SPSS 20.0 software was used for statistical analysis. Results:Among the 98 controls, 9 (9.18%) were positive for pathogenic microorganisms, including 1 (1.02%) rhinovirus, 1 (1.02%) parainfluenza virus type 3, 3 (3.06%) enterovirus, 1 (1.02%) staphylococcus aureus and 3 (3.06%) Moraxella catarrhalis. Among the 234 URI patients, 111 (47.44%) had olfactory disorders and 123 (52.56%) had normal sense of smell. In the olfactory disorder group (111 cases), 38 cases (34.23%) were positive for pathogenic microorganisms, and 4 cases (3.60%) were mixed infection, including 11 cases of rhinovirus (9.91%), 5 cases of coronavirus 229E (4.50%), 2 cases of coronavirus OC43/NL63 (1.80%), 3 cases of parainfluenza virus type 1 (2.70%), 2 cases of enterovirus (1.80%), 1 case of influenza B virus type BV (0.90%), 11 cases of Staphylococcus aureus (9.91%), 7 cases of Moraxella catarrhalis (6.31%), and 1 case of Klebsiella pneumoniae (0.90%). In the normal smell group (123 cases), 18 cases (14.63%) were positive for pathogenic microorganisms, and 1 case (0.81%) was mixed infection, including 3 cases of rhinovirus (2.44%), 4 cases of coronavirus 229E (3.25%), 1 case of Influenza virus type 3 (0.81%), 3 cases of enterovirus (2.44%), 3 cases of Staphylococcus aureus (2.44%), 4 cases of Moraxella catarrhalis (3.25%), and 1 case of Klebsiella pneumoniae (0.81%). Univariate analysis between the two groups found that there were significant differences in the detection rate of pathogenic microorganisms, rhinovirus and Staphylococcus aureus between the groups (all P<0.05). The detection rate of parainfluenza virus type 1, Staphylococcus aureus, and rhinovirus were different between the patients with olfactory disorder and normal olfactory function in the three subgroups of acute upper respiratory tract infection, CRS and AR, respectively (χ 2 value was 3.88, 4.53 and 4.73, respectively, all P<0.05). During the follow-up period, among the 111 patients with olfactory disorder, 71 (63.96%) patients′ olfactory function returned to normal, 32 (28.83%) patients′ olfactory function improved but not completely returned to normal, 8 (7.21%) patients′ olfactory function did not improve. Conclusions:During the prevention and control of COVID-19, rhinovirus or Staphylococcus aureus infection or colonization of URI patients is closely related to olfactory disorders. Parainfluenza virus type 1 infection can cause relatively persistent olfactory disorders in patients with acute upper respiratory tract infection. Staphylococcus aureus and rhinovirus colonization are related to the occurrence of olfactory dysfunction in CRS and AR patients respectively.