Activation of CaMKIIδA promotes Ca2+ leak from the sarcoplasmic reticulum in cardiomyocytes of chronic heart failure rats.

Activation of the Ca2+/calmodulin-dependent protein kinase II isoform δA (CaMKIIδA) disturbs intracellular Ca2+ homeostasis in cardiomyocytes during chronic heart failure (CHF). We hypothesized that upregulation of CaMKIIδA in cardiomyocytes might enhance Ca2+ leak from the sarcoplasmic reticulum (SR) via activation of phosphorylated ryanodine receptor type 2 (P-RyR2) and decrease Ca2+ uptake by inhibition of SR calcium ATPase 2a (SERCA2a). In this study, CHF was induced in rats by ligation of the left anterior descending coronary artery. We found that CHF caused an increase in the expression of CaMKIIδA and P-RyR2 in the left ventricle (LV). The role of CaMKIIδA in regulation of P-RyR2 was elucidated in cardiomyocytes isolated from neonatal rats in vitro. Hypoxia induced upregulation of CaMKIIδA and activation of P-RyR2 in the cardiomyocytes, which both were attenuated by knockdown of CaMKIIδA. Furthermore, we showed that knockdown of CaMKIIδA significantly decreased the Ca2+ leak from the SR elicited by hypoxia in the cardiomyocytes. In addition, CHF also induced a downregulation of SERCA2a in the LV of CHF rats. Knockdown of CaMKIIδA normalized hypoxia-induced downregulation of SERCA2a in cardiomyocytes in vitro. The results demonstrate that the inhibition of CaMKIIδA may improve cardiac function by preventing SR Ca2+ leak through downregulation of P-RyR2 and upregulation of SERCA2a expression in cardiomyocytes in CHF.

Correlation and pathways of behavioral activation systems mediating physical activity level and depressive symptoms among college students.

BACKGROUND: Depression is a common mental disorder among college students. The main symptoms include being persistent low mood, sad emotional experiences, lack of pleasure, listlessness, and impaired cognitive function accompanied by tendencies of self-harm and suicide. AIM: To clarify the pathways and effects of the behavioral activation system between physical activity and depressive symptoms in college students with depressive symptoms. METHODS: This cross-sectional research screened 3047 college students. Of these, 472 had depressive symptoms, with a depression detection rate of 15.49%. Furthermore, 442 college students with depressive symptoms were analyzed. A one-way analysis of variance and Pearson's correlation, linear regression, and structural equation modeling analyses were used to explore the correlations and pathways of the interactions between the variables. RESULTS: Depressive symptoms were significantly negatively correlated with physical activity (r = -0.175, P < 0.001), the behavioral activation system (r = -0.197, P < 0.001), and drive (r = -0.113, P = 0.017). Furthermore, it was negatively correlated with fun-seeking (FS) (r = -0.055, P = 0.251); however, it was not significant. Physical activity was significantly positively correlated with reward responsiveness (RR) (r = 0.141, P = 0.003) and drive (r = 0.124, P = 0.009) and not significantly positively correlated with FS (r = 0.090, P = 0.058). The mediating effect of RR between physical activity and depressive symptoms was significant [B = -0.025, 95% confidence interval (95%CI): -0.051 to -0.008, P = 0.001]. The direct and total effects of physical activity on depressive symptoms and were significant (B = -0.150, 95%CI: -0.233 to -0.073, P < 0.001; B = -0.175, 95%CI: -0.260 to -0.099, P < 0.001), respectively. CONCLUSION: As physical activity levels increased, depression scores among college students decreased. The mediating effect of RR between physical activity and depressive symptoms was significant. Therefore, colleges and universities should encourage college students with depression to increase their physical activity and improve their behavioral activation system. Particular attention should be paid to RR, which may reduce the prevalence of depressive symptoms.

Anterior positioning screw in proximal femoral plating restricts posterior tilt of retroverted femoral neck fractures: a retrospective cohort study.

BACKGROUND: Preoperative posterior tilt is a risk factor for fixation failure in femoral neck fractures. This study aimed to evaluate the configuration of anterior positioning screw in proximal femoral plating in the treatment of retroverted femoral neck fractures in terms of resisting posterior tilt. METHODS: We retrospectively analyzed patients with retroverted femoral neck fractures who were fixed by proximal femoral plating from January 2014 to August 2019. All patients were divided into two groups according to screw configuration: anterior long-threaded screw (ALTS, n = 36) and normally short-threaded screws (NTS, n = 46). Baseline characteristics were reviewed and radiological and clinical outcomes were analyzed. Logistic regression analysis was used to identify risk factors for developing posterior tilt. RESULTS: Age, gender, Garden classification, posterior comminution, and reduction quality showed no significant difference between the groups. Increased posterior tilt was lower in the ALTS group (3.2°, 2.1-4.3°) than that in the NTS group (5.3°, 4.2-8.3°) (p < 0.001), and the percentage of people with > 5° of posterior tilt was also lower in the ALTS group (5, 13.9% vs. 24, 52.2%; p < 0.001). Femoral neck shortening (FNS) was lower in the ALTS group (3.1 (2.1-4.7) mm vs. 4.3 (3.1-6.3) mm, p = 0.003), though not statistically significant when using 5 mm as the cut-off value. Harris Hip Score in the ALTS group was higher than that in the NTS group (87.0, 84.0-90.0 vs. 82.0, 76.0-84.5; p < 0.001). Postoperative complications including delayed union, nonunion, and avascular necrosis were comparable between the groups. Multivariable analysis identified posterior comminution (OR 15.9, 95% CI 3.6-70.3, p < 0.001), suboptimal reduction quality (OR 12.0, 95% CI 2.6-56.1, p = 0.002), and NTS configuration (reference: ALTS configuration) (OR 21.9, 95% CI 4.1-116.4, p < 0.001) as risk factors for developing posterior tilt. CONCLUSIONS: Configuration of anterior positioning screw in proximal femoral plating provides better resistance against posterior tilt in the fixation of retroverted femoral neck fractures. Also, posterior comminution, suboptimal reduction, and NTS configuration (reference: ALTS) are risk factors for developing posterior tilt. TRIAL REGISTRATION: The trial registration number was ChiCTR2000039482 .

Dynamic limited axial compression yields favorable functional outcomes in the fixation of Pauwels type-3 femoral neck fractures: A retrospective cohort study.

PURPOSE: Pauwels type-3 femoral neck fractures are challenging injuries to manage with high rates of complications after internal fixation and no consensus has been reached regarding the optimal fixation construct. The current study aims to evaluate the effect of dynamic limited axial compression in parallel screws combined with medial buttress plate (SMBP) or lateral compression plate (LCP) fixation of Pauwels type-3 femoral neck fractures. METHODS: We performed a retrospective analysis of 51 cases of Pauwels type-3 femoral neck fractures who were fixed by SMBP or LCP. Specifically, the screw fixing the femoral head in the buttress plate was omitted. Postoperative complications and functional outcomes were mainly studied. RESULTS: With a mean follow-up of 19.9 months, the rate of neck shortening was higher in the LCP group than that in SMBP group (32.1% vs. 8.7%, p = 0.04). Neither nonunion nor avascular necrosis was observed in both groups. Good-to-excellent Harris hip score accounts for 95.2% in SMBP group and 89.3% in LCP group (p = 0.40). Moreover, older age, fracture comminution and compression plate fixation predispose to neck shortening. CONCLUSION: Dynamic limited axial compression by SMBP or LCP fixation was effective to improve the functional outcome of patients with Pauwels type-3 femoral neck fractures.

[Effects of different anesthetic methods and anesthetic drugs on stress reaction during surgical operation].

OBJECTIVE: To investigate the effect of four different anesthetic methods (combined epidural with general anesthesia with endotracheal intubation or with laryngeal mask airway, total intravenous anesthesia or remifentanil intravenous infusion combined with inhalational anesthesia) on stress reaction in patients undergoing upper abdominal surgery. METHODS: Sixty ASAI-II patients, aged 18 - 65 y, scheduled for elective upper abdominal surgery were enrolled in the study. They were divided into four groups: epidural combine general anesthesia with intubation group (EG group) and with laryngeal mask group (EGL group), total intravenous remifentanil combined with propofol (RP group) and inhalational group (RI group). Blood pressure, ECG, SpO(2), PETCO(2) were monitored continuously. Level of epinephrine and norepinephrine, angiotensin I and angiotensin II, glicentin and blood glucose in blood plasma were measured before operation, after induction, after skin incision and at the end of operation. RESULTS: The Blood pressure in RP and RI groups was lower than that in EG and EGL groups at induction. Blood pressure and heart rate of EG group were higher than those in RP, RI and EGL groups during intubation. Heart rate of RP group changed least than the other groups at skin incision. Heart rate of EGL group was higher than that in the other groups at extubation. Epinephrine and norepinephrine were lowered slightly at intubation and skin incision, and were raised at the end of operation in all groups. Norepinephrine of RP group increased distinctly compared with preoperative level. Glicentin was decreased slightly at intubation in all groups, and dropped to the lowest at the end of operation, glicentin in RP group was decreased significantly compared with preoperative level. Blood glucose was lowered slightly at induction and intubation, and was raised distinctly at the end of operation in four groups. Glucagon and Blood glucose of RP and RI groups were lower than those of EG and EGL groups. CONCLUSION: Different anesthetic methods and anesthetic drugs had different effects on stress reaction (hormones) during surgical operation. Regardless of general anesthesia or intrathecal anesthesia, harmful stimulus could not be completely blocked by the intraoperative management and stress regulation during operation. Intrathecal anesthesia combined with general anesthesia could inhibit the stress reaction during upper abdominal surgery. Continuous remifentanil target controlled infusion could inhibit the degree of stress reaction, either.

A self-assembled amphiphilic imidazolium-based ATP probe.

A novel amphiphilic imidazolium-based probe containing a dansyl fluorophore and a long cetyl chain has been developed for ATP recognition. The probe forms self-assembled micelle-like aggregates at low concentration in its aqueous solution and can selectively recognize ATP among other bioactive anions with a significant enhancement in fluorescence emission.

A Pyrene-functionalized Polynorbornene for Ratiometric Fluorescence Sensing of Pyrophosphate.

A novel pyrene-functionalized polynorbornene (P1) bearing sulfonamide NH and triazolium donors has been synthesized for ratiometric fluorescence sensing of PPi in aqueous solution. In addition, P1 is also used to monitor intracellular PPi and to detect PPi released during polymerase chain reaction.

[intercellular adhesion molecule-1 and CD11a/CD18 expression in coronary heart disease]

OBJECTIVE: To investigate the expression of soluble intercellular adhesion molecule-1(sICAM-1) and CD11a/CD18 in coronary heart disease(CHD). METHODS: The sICAM-1 and CD11a/CD18 levels were measured by ELISA and flow cytlemetry in 76 CHD patients and 65 healthy subjects. RESULTS: The level of sICAM-1 and CD11a/CD18 were significantly higher in CHD patients than healthy subjects [SICAM-1(g/L):263.5 +/-66.2 compared with 205.9 +/-57.2, P<0.01; CD11a/CD18 (%):33.7 +/-6.4 compared with 19.3 +/-8.1, P<0.001]. They were also significantly higher in acute myocardial infarct and unstable angina than that of stable angina patients. There was correlation between sICAM-1 and CD11a/CD18(r=0.436, P<0.01). CONCLUSION: Elevated levels of sICAM-1 and CD11a/CD18 associated with unstable angina and myocardial infarction may indicate their significant role in the pathogenesis of acute coronary events.

A Highly Selective and Sensitive Turn-On Fluorescent Chemosensor Based on Rhodamine 6G for Iron(III).

Recently, more and more rhodamine derivatives have been used as fluorophores to construct sensors due to their excellent spectroscopic properties. A rhodamine-based fluorescent and colorimetric Fe(3+) chemosensor 3',6'-bis(ethylamino)-2-acetoxyl-2',7'-dimethyl-spiro[1H-isoindole-1,9'-[9H]xanthen]-3(2H)-one (RAE) was designed and synthesized. Upon the addition of Fe(3+), the dramatic enhancement of both fluorescence and absorbance intensity, as well as the color change of the solution, could be observed. The detection limit of RAE for Fe(3+) was around 7.98 ppb. Common coexistent metal ions showed little or no interference in the detection of Fe(3+). Moreover, the addition of CN(-) could quench the fluorescence of the acetonitrile solution of RAE and Fe(3+), indicating the regeneration of the chemosensor RAE. The robust nature of the sensor was shown by the detection of Fe(3+) even after repeated rounds of quenching. As iron is a ubiquitous metal in cells and plays vital roles in many biological processes, this chemosensor could be developed to have applications in biological studies.