[Mesogastrium theory of D2 lymphadenectomy for advanced gastric cancer: cogitation and skills]

D2 lymphadenectomy combined with complete mesentery excision (CME) for advanced gastric cancer in recent years was a hotspot issue in China, while its safety and effectiveness have been proved. According to the Membrane anatomy of the stomach, both surgical approach and mesogastrium interval is particularly important in Laparoscopic radical gastrectomy. We summarized and shared the following clinical experience for medical colleagues. (1) Lymph nodes of right abdominal aorta-No.7,8,9,12-should be resection as an indivisible whole. This integrity tissue above the portal vein was supposed to the end of the dorsal mesentery of stomach and the continuation of Gerota fascia. (2) No.10 (splenic hilar lymph nodes) lymphadenectomy: The surgical approach enters the Gerota fascia between the left gastric artery(LGA) and the left alongside the splenic artery. When the extent of lymphadenectomy performed to cardia and upper margin of the spleen, then the ultrasonic scalpel should excise the lymph node along the splenic artery to the splenic hilum. (3) Esophagogastric junctional cancer: There is no consensus over the type of resection and the extent of lymphadenectomy that could be a standard of care for this category.While we recommended that paraesophageal lymph node dissection and digestive tract reconstruction should be completed in 3D laparoscopy vision. (4) Infracardiac bursa(ICB): Intentional entry into the ICB provides surgeons with a landmark to identify the location of the pleura, and inferior vena cava. (5)The application of endoscopic aspirator with flushing and electrocautery. The CME concept of gastric cancer emphasizes the membrane anatomy theory rather than the regional lymph node. The precision and homogeneity of the D2 procedure therapy of gastric cancer depend on complete mesentery excision, standard the surgical process, or approach. Only in this way can we find the avascular gaps easily and perfectly cover the extent of lymph node dissection required for the D2 procedure.

Association between increased levels of amyloid-β oligomers in plasma and episodic memory loss in Alzheimer's disease

Objective

The objectives of this study were to investigate whether the plasma levels of oligomeric amyloid-β (OAβ) were affected in Alzheimer’s disease (AD) and to examine the associations (or possible correlations) between plasma OAβ levels and memory performance.

Method

Thirty subjects with AD and 28 cognitively normal controls were recruited in the study. The multimer detection system (MDS) was used to measure the levels of OAβ in the plasma. In addition to assessing the general cognitive function with the Mini-Mental State Examination (MMSE), Cognitive Abilities Screening Instrument (CASI), and Alzheimer’s Disease Assessment Scale–cognitive portion (ADAS-Cog), the common objects memory test (COMT) was used to examine the episodic memory performance. Pearson’s and partial correlation analyses were conducted to explore the associations between cognitive performance and OAβ levels in the plasma. A receiving operating curve (ROC) analysis was used to discriminate between the AD and control groups.

Results

The plasma OAβ levels in the AD group were significantly higher than those in the control group [1.88 (0.38) ng/ml vs 1.20 (0.40) ng/ml, p < 0.001]. The elevated levels of plasma OAβ showed a strong correlation with cognitive performance in patients with AD, including an inverse correlation with scores on the MMSE (r = − 0.43, p = 0.02), CASI (r = − 0.56, p < 0.01), and the immediate recall (r = − 0.45, p = 0.01), 5-min delayed recall (r = − 0.56, p < 0.01), and 30-min delayed recall (r = − 0.71, p < 0.001) tests of the COMT, and a positive correlation with the ADAS-Cog scores (r = 0.59, p < 0.001). The EDTA plasma Aβ oligomer optical density (OD) value measured using the MDS could discriminate between the AD and control groups with an area under the curve (AUC) of 0.89. The optimal sensitivity and specificity were 82.1% and 90.0%, respectively.

Conclusion

The elevated levels of OAβ in the plasma distinguished the AD and control groups and were associated with the severity of symptoms, especially memory performance, in patients with AD. Our results suggested that plasma OAβ could potentially be a simple and non-invasive blood-based biomarker for AD diagnosis. Furthermore, longitudinal studies are warranted to explore the application of plasma OAβ levels as a valid diagnostic biomarker in patients with AD.

Electronic supplementary material

The online version of this article (10.1186/s13195-019-0535-7) contains supplementary material, which is available to authorized users.

[Comparative study on the efficacy and safety between pegfilgrastim (PEG-rhG-CSF) and recombinant human granulocyte colony-stimulating factor in promoting hematopoietic recovery after allogeneic hematopoietic stem cell transplantation after hematological malignancy]

Objective: To observe the efficacy and safety between Pegfilgrastim (PEG-rhG-CSF) and Recombinant human granulocyte colony stimulating factor (rhG-CSF) in hematological malignancy after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: 157 patients after allo-HSCT were enrolled in this study from June 2015 to November 2016. Two agents of G-CSF were used to stimulate hematopoietic recovery after transplantation. There were 65 cases in PEG-rhG-CSF and 92 cases in rhG-CSF groups. Patients in PEG-rhG-CSF group were given a single subcutaneous dose of 6 mg on the first day and +8 d, while cases in rhG-CSF group were given in dose of 5 μg·kg(-1)·d(-1) by subcutaneous injection from +1 d continuing to neutrophils more than 1.5×10(9)/L, and then the indicators and survival rates in two groups after transplantation were compared. Results: ①There were no significant differences of the neutrophil implantation time[13.5 (8-12) d vs 13 (9-24) d, P=0.393] and platelet implantation time [14 (9-160) d vs 14 (9-92) d, P=0.094] between PEG-rhG-CSF and rhG-CSF groups respectively. There were no significant differences in terms of neutropenia period (P=0.435) , number of cases who got fever during neutropenia (P=0.622) , and the median time of fever in neutropenia period (P=0.460) , respectively between the two groups. There were no significant differences of erythrocyte and platelet transfusions (P=0.074, P=0.059) within 1 month after transplantation. ②There were no significant differences with regard to the incidences of acute GVHD[23.1% (15/65) vs 34.8% (32/92) , P=0.115], chronic GVHD[20.0% (13/65) vs 32.6% (32/92) , P=0.081], Ⅱ-Ⅳdegree of acute GVHD[30.0% (13/65) vs 30.4% (30/92) , P=0.287] and extensive chronic GVHD[9.2% (6/65) vs 20.7% (19/92) , P=0.135] between PEG-rhG-CSF and rhG-CSF groups. ③There were no significant differences in terms of disease free survival (DFS) (62.5% vs 61.4%, P=0.478) and overall survival (OS) (67.4% vs 67.3%, P=0.718) between PEG-rhG-CSF and rhG-CSF groups. ④There was no significant difference of the non-relapse mortality (NRM) between PEG-rhG-CSF and rhG-CSF groups[20.5% (95%CI 11.4%-37.0%) vs 32.6% (95%CI 22.2%-47.9%) , P=0.141]. The relapse rate was not statistically significant[14.9% (95%CI 7.4%-29.8%) vs 10.0% (95%CI 5.0%-20.0%) , P=0.299]. Conclusion: Compared with rhG-CSF, PEG-rhG-CSF could reduce the times of injection. There were no differences in terms of hematopoietic recovery, the incidence of GVHD, relapse rate, DFS and OS rates after allo-HSCT between two groups.

Scaffolding adapter protein Gab1 impairs bFGF-induced bio-activity via affecting PI3K-AKT pathway

The role of Grb2-associated binder 1 (Gab1) in bFGF-activated PI3K-AKT pathway of endothelial cells remains largely unknown. To elucidate this role, a set of studies with siRNA knockdown of Gab1 was performed. Knockdown of Gab1 using siRNA was performed in fused endothelial cell line EA.hy926 and the low level of Gab1 was confirmed with quantitative R-T PCR and Western blotting. Effects of Gab1 down-regulation were examined on several aspects: bFGF-induced AKT phosphorylation, proliferation, migration and vessel tubing formation of EA.hy926 cells. The bFGF-induced AKT phosphorylation of wild-type EA.hy926 cells was both dose-dependent and time dependent with a peak at 10 ng/ml and about 30 min after bFGF treatment. The AKT activation was significantly reduced in Gab1 siRNA-treated EA.hy926 cells. The blocking of Gab1-AKT path resulted in a set of biological alterations of EA.hy926 cells: (i) reduced proliferation; (ii) impaired migration; (iii) decreased vessel tubing formation in both 2D and 3D culture. All data support that Gab1 is associated with angiogenesis function of EA.hy926 endothelium cells via PI3K-Akt signaling pathway.

[A study on the effects and safety of sequential humidified high flow nasal cannula oxygenation therapy on the COPD patients after extubation]

Objective: To investigate and compare the effect and safety of nasal high-flow oxygen therapy (HFNCO) and noninvasive ventilation (NIV) therapy after extubation in patients with chronic obstructive pulmonary disease (COPD). Methods: All COPD patients subjected to mechanical ventilation in the Emergency Intensive Unit of the First Affiliated Hospital of Zhejiang University during January 2015 to June 2016 were included in the study. The patients were divided into two groups after extubation and HFNCO and NIV were adopted on each group respectively. Clinical indexes including the patients' general condition, blood gas analysis and pulmonary function before and after extubation, ratio of re-intubation and CT grades were collected and analyzed. Results: There was no significant difference in the incidence of aspiration (4.8% vs 8.3%), pressure sores (0 vs 8.3%) and delirium (4.8% vs 12.5%) between the two groups (all P>0.05). At 12 h after extubation, the oxygenation index of NIV group was significantly higher than that of the HFNCO group (265±29 vs 297±33; P<0.05), while no significant difference in PCO(2) (P>0.05). For 24 h and 72 h after extubation, there was no statistically significant difference in oxygenation index and PCO(2) between the both groups (P>0.05). The intensive care unit (ICU) retention time in HFNCO group was significantly lower than that in NIV group (13.7±0.8 vs 15.2±0.5; P<0.05). In addition, no significant difference between the two groups in mortality and re-intubation rate at 28 d (P>0.05) was observed. Conclusion: HFNCO is effective and safe in the treatment of COPD patients after extubation, and it is hence valuable for further clinical application.

Soluble CD163 Levels and CD163+CD14+ Monocyte/Macrophage Counts in Patients with Asthma

BACKGROUND

CD163-expressing macrophages are involved in the inflammatory response in asthma.

OBJECTIVE

To assess sputum and serum soluble CD163 (sCD163) and cytokine levels in patients with asthma. Further discussed was the difference between sCD163 and other classic inflammatory mediators.

METHODS

Sputum was successfully induced in asthma patients (n=85) and healthy controls (n=21). Interleukin (IL)-4, IL-5, IL-1β, IL-8, IL-9, IL-6, and sCD163 levels in sputum were measured. CD163+ monocytes in blood were evaluated using flow cytometry.

RESULTS

Sputum sCD163 level significantly increased in asthma (median: 22.4 pg/ml; IQR, 11.52-42.91), unlike healthy controls (10.54 pg/ml;9.85-23.5; P<0.001). Sputum sCD163 (P=0.020) and serum sCD163 (P=0.032) levels were significantly higher in patients with severe asthma compared to those with mild/moderate asthma. Percentage of CD163+ monocytes in patients with asthma was significantly lower than the controls (P<0.001).

CONCLUSION

Increased sCD163 levels in sputum are associated with the impairment of lung function.

[The predictive value of parathyroid hormone levels and decreases for postoperative hypocalcemia after total thyroidectomy]

Objective:To investigate the predictive value of parathyroid hormone levels and decreases for postoperative hypocalcemia after total thyroidectomy. Method:We reviewed 71 consecutive patients who underwent total thyroidectomy, measured postoperative hypocalcemia, parathyroid hormone (PTH) values within 24 hours after surgery, divided them into subgroups accroding to hypocalcemia symptom. Combining with postoperative serum calcium，postoperative PTH values and decreases (△PTH), we used the receiver operating characteristic curve (ROC) analysis to assessment of predictive value. Result:The mean value of postoperative serum calcium, postoperative PTH and △PTH between subgroups have a significant difference (P<0.01). ROC area under the curve (AUC) of △PTH is 0.9706, with cutoff value 0.7366. AUC of postoperative PTH is 0.9580, with cutoff value 14.82 ng/L. Conclusion:The postoperative PTH and △PTH is a reliable indicator to judging postoperative hypocalcemia after total thyroidectomy.

Evidence for weak collective pinning and δl pinning in topological superconductor Cu x Bi2Se3

We investigated the vortex pinning behavior in the single crystal topological superconductor Cu_0.10Bi₂Se₃ with a pronounced anisotropic peak effect. A weak collective pinning regime is clarified from the power-law behavior in [Formula: see text] and the small critical current density ratio of [Formula: see text] ~ 10^-5 ([Formula: see text] is the critical current density, [Formula: see text] is the depairing current density). The spatial variation of the charge-carrier mean free path induced pinning is evidenced and probably results from the well-defined atomic defects. Within the framework of collective pinning theory, we computed the values of the correlated length and volume at 1.8 K, which start declining prior to the onset field of the peak effect [Formula: see text], demonstrating the vortex lattices already suffered a preferential collapse ahead of the peak effect turns up. Thus, the peak effect can be understood by elastic moduli softening near the upper critical field [Formula: see text]. We suggest Cu _x Bi₂Se₃ is a prototype topological material for investigating the vortex pinning dynamics associated with the peak effect phenomenon.

Periodontitis aggravates kidney damage in obese mice by MMP2 regulation

OBJECTIVE

  To investigate the effect of periodontitis on the development of kidney damage in obese mice and its possible mechanism.

METHODS

  C57 BL/6J mice were fed high‑fat (HF) or low‑fat (LF) diet and then divided into four groups:  obesity with periodontitis (HFP), obesity without periodontitis (HFC), normal mice with periodontitis (LFP) and normal mice without periodontitis (LFC). Serum indicators of renal function, namely serum total protein (TP), albumin (ALB), creatinine (Cr) and blood urea nitrogen (UREA) were measured. The histopathological examination of kidney tissues was performed. The expressions of transforming growth factor-β1 (TGF-β1), matrix metalloproteinase-2 (MMP2) and tissue inhibitors of metalloproteinases-1 (TIMP1) were detected by immunohistochemistry and real time RT-PCR.

RESULTS

  Obesity decreased TP and ALB, and increased serum Cr and UREA levels in normal and periodontitis mice groups, as well as induced glomerular and tubulointerstitial pathologic changes. Tubulointerstitial fibrosis was more severe in HFP group. In obese mice, periodontitis caused the downregulation of MMP2, and upregulation of TIMP1 and TGF-β1 at transcriptional and translational levels.

CONCLUSIONS

  In obese mice, periodontitis may aggravate pathological changes in the kidney. The possible mechanism might lie in downregulation of MMP2 and upregulation of MMP inhibitor, TIMP1, and TGF-β1 (Tab. 1, Fig. 4, Ref. 16).

Magnetotransport study of topological superconductor Cu0.10Bi2Se3 single crystal

We report a magnetotransport study of vortex-pinning in Cu_0.10Bi₂Se₃ single crystal. The sample is demonstrated to be in clean limit and absent of Pauli spin-limiting effect. Interestingly, the resistivity versus magnetic field shows an anomalously pronounced increase when approaching the superconducting-normal state boundary for both [Formula: see text] and [Formula: see text] configurations. We have investigated the flux-flowing behavior under various magnetic fields and temperatures, enabling us to establish its anisotropic vortex phase diagram. Our results suggest the Cu_0.10Bi₂Se₃ can be served as one unique material for exploring exotic surface vortex states in topological superconductors.

Carpal tunnel release with a new mini-incision approach versus a conventional approach, a retrospective cohort study

PURPOSE

We have make use of a new method to perform carpal tunnel release (CTR) through a 1.5-2.0 cm long incision The aim of this study is to introduce this method and to compare the effectiveness and safety of this approach to the conventional one.

METHODS

We included consecutive patients diagnosed with primary carpal tunnel syndrome (CTS) who had CTR from January 2015 to September 2016. A total of 85 patients were included in our study. Among them, 42 patients with mini-incision approach were enrolled in group A, and the other 43 patients with conventional approach were enrolled in group B. Objective tests and subjective evaluations were performed to compare the outcomes of mini-incision approach with the conventional approach. Postoperative complications after the two approaches were also compared.

RESULTS

At the 12-months follow-up, all patients in both groups got recovery. We found no significant differences between the two groups in postoperative pinch strength, grip strength, 2-point discrimination (2-PD), visual analogue scale (VAS) score, Levine score and the Disabilities of the Arm, Shoulder and Hand (DASH) score (P > 0.05). However, at the one-month follow-up, the percentage of patients with wound pain in group A was significantly lower than that in group B (0.05% vs. 0.23%, P = 0.03). At the 12 months follow-up, the number of patients with persistent wound pain and pillar pain in group B were 2 (4.7%) and 3 (7.0%) respectively, while no patients showed wound pain and pillar pain in group A.

CONCLUSION

Patients with mini-incision approach have satisfactory surgical outcomes, low postoperative complications, and good appearance.

Predictors of surgical outcomes after in situ ulnar nerve decompression for cubital tunnel syndrome

Background

In the treatment of cubital tunnel syndrome (CuTS), in situ ulnar nerve decompression is commonly used. This study aims to investigate predictive factors for poor recovery and ulnar nerve instability following this procedure.

Methods

We enrolled 235 patients who underwent in situ ulnar nerve decompression for the treatment of CuTS from January 2010 to December 2014. All patients underwent >2 years' follow-up. The primary outcome was postoperative recovery, which was assessed by Messina's criteria, and the secondary outcome was postoperative ulnar nerve instability. Potential risk factors were collected from demographic data and electrodiagnostic test, which included age, gender, body mass index, history of tobacco or alcohol use, history of major medical comorbidities, disease duration, preoperative severity, motor conduction velocity, and sensory conduction velocity.

Results

A total of 208 patients (88.5%) had satisfactory outcomes, while the other 27 patients (11.5%) had not. There were 25 patients (10.6%) showing postoperative ulnar nerve instability during follow-up. The multivariate analysis showed that only severe preoperative symptom (odds ratio [OR], 3.06; 95% confidence interval [CI], 2.16-4.32) was associated with unsatisfactory postoperative outcomes in patients with CuTS (P<0.001). In the model investigating independent factors associated with postoperative ulnar nerve instability, we found that young age (OR, 2.41; 95% CI, 1.63-3.58) was associated with the incidence of postoperative ulnar nerve instability (P<0.001).

Conclusion

We found that severe preoperative symptom was associated with unsatisfactory postoperative outcomes, and young age was a risk factor for the incidence of postoperative ulnar nerve instability. Patients with these risk factors should be informed of the possibility of worse surgical outcomes.

Ultrathin graphene-based membrane with precise molecular sieving and ultrafast solvent permeation

Graphene oxide (GO) membranes continue to attract intense interest due to their unique molecular sieving properties combined with fast permeation. However, their use is limited to aqueous solutions because GO membranes appear impermeable to organic solvents, a phenomenon not yet fully understood. Here, we report efficient and fast filtration of organic solutions through GO laminates containing smooth two-dimensional (2D) capillaries made from large (10-20 μm) flakes. Without modification of sieving characteristics, these membranes can be made exceptionally thin, down to ∼10 nm, which translates into fast water and organic solvent permeation. We attribute organic solvent permeation and sieving properties to randomly distributed pinholes interconnected by short graphene channels with a width of 1 nm. With increasing membrane thickness, organic solvent permeation rates decay exponentially but water continues to permeate quickly, in agreement with previous reports. The potential of ultrathin GO laminates for organic solvent nanofiltration is demonstrated by showing >99.9% rejection of small molecular weight organic dyes dissolved in methanol. Our work significantly expands possibilities for the use of GO membranes in purification and filtration technologies.

[Effect of thermal conductivity on apical sealing ability of 4 dental gutta-percha cones]

OBJECTIVE

To investigate the effect of thermal conductivity on the apical sealing ability of different dental gutta-percha cones during the warm vertical condensation obturation.

METHODS

Four kinds of dental gutta-percha cones were used in this study: Bio-GP points (BP, B&L, Korea), large-tapered gutta-percha (DP, DENTSPLY, America), PROTAPER Universal gutta-percha points (DPP, DENTSPLY, America) and mtwo gutta-percha points (VP, VDW, Germany). Volume differences method was used to determine the main components and the thermal conductivity determinator was used to measure the thermal conductivity of these dental gutta-percha cones. Furthermore, 20 cones randomly selected from each kind of dental gutta-percha cones. And 10 cones of each dental gutta-percha cones, which were cut out the part of 4 mm in length from the apical end, were heated (200 °C) from the upper end without compression, and the temperature of the gutta perchacones surface was monitored in time by the infrared thermal imager during the whole heating process. In addition, the rest of the 10 cones of each dental gutta-percha cones were used to obturate the root canal in the transparent root canal resin model using warm vertical condensation technique. The cross-sectional surface was observed by stereomicroscope (× 40) at 1 mm and 3 mm from the working length and the gutta-percha obturation area proportion was measured and analyzed. The data were analyzed by one-way ANOVA.

RESULTS

The proportion of inorganic fillers (80.90%±1.14 %) (P<0.05) and the thermal conductivity (2.247±0.002) of DP was significantly higher than BP (79.28%±3.88%, 1.179±0.003), DPP (68.46%±5.09%, 0.604±0.001), VP (78.86%±1.87%, 1.150±0.001) (P<0.05). During the thermal obturation without compression at the setting temperature (200 °C), DP could achieve 65 °C beyond 1 mm from the heating point, and BP, DPP and VP only reached 65 °C within 1 mm. After warm vertical condensation obturation, all the groups showed increased gutta-percha obturation area proportion. At the position of WL-3, DP (96.89%±0.03%) showed significantly higher proportion of gutta-percha obturation area than BP (95.47%±0.06%), DPP (95.21%±0.03%) and VP (95.15%±0.03%) (P<0.05).

CONCLUSION

DP contains more inorganic fillers, possesses higher thermal conductivity, and leads a better apical sealing ability than BP,DPP and VP at the position of WL-3 during warm vertical condensation obturation.

Hybrid Pixel-Waveform (HPWF) Enabled CdTe Detectors for Small Animal Gamma-Ray Imaging Applications

This paper presents the design and preliminary evaluation of small-pixel CdTe gamma ray detectors equipped with a hybrid pixel-waveform (HPWF) readout system for gamma ray imaging applications with additional discussion on CZT due to its similarity. The HPWF readout system utilizes a pixelated anode readout circuitry which is designed to only provide the pixel address. This readout circuitry works in coincidence with a high-speed digitizer to sample the cathode waveform which provides the energy, timing, and depth-of-interaction (DOI) information. This work focuses on the developed and experimentally evaluated prototype HPWF-CdTe detectors with a custom CMOS pixel-ASIC to readout small anode pixels of 350 μm in size, and a discrete waveform sampling circuitry to digitize the signal waveform induced on the large cathode. The intrinsic timing, energy, and spatial resolution were experimentally evaluated in this paper in conjunction with methods for depth of interaction (DOI) partitioning of the CdTe crystal. While the experimental studies discussed in this paper are primarily for evaluating HPWF detectors for small animal PET imaging, these detectors could find their applications for ultrahigh-resolution SPECT and other imaging modalities.

Rapid and Sustained Antidepressant Action of the mGlu2/3 Receptor Antagonist MGS0039 in the Social Defeat Stress Model: Comparison with Ketamine

BACKGROUND

Similar to the N-methyl-D-aspartate receptor antagonist ketamine, the metabotropic glutamate 2/3 receptor antagonist, MGS0039, shows antidepressant effects. However, there are no reports comparing these 2 compounds in the social defeat stress model of depression.

METHODS

We examined the effects of MGS0039 (1 mg/kg) and ketamine (10 mg/kg) on depression-like behavior in susceptible mice after repeated social defeat stress. Protein levels of brain-derived neurotrophic factor, TrkB, phospho-TrkB, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (GluA1), postsynaptic density protein 95, and dendritic spine density in selected brain regions were measured.

RESULTS

In the tail suspension and forced swimming tests, both MGS0039 and ketamine significantly attenuated the increased immobility time observed in susceptible mice, compared with vehicle-treated animals, 1 or 2 days after a single dose of drug. In the sucrose preference test, both compounds significantly improved the reduced preference typically seen in susceptible mice at 3 to 7 days after a single dose of drug. Western-blot analyses showed that similar to ketamine, MGS0039 significantly attenuated the reduced brain-derived neurotrophic factor, phospho-TrkB/TrkB ratio, GluA1 and postsynaptic density protein 95 seen in the prefrontal cortex, dentate gyrus, and CA3 of the hippocampus from susceptible mice, 8 days after a single dose. Again, in a similar manner to ketamine, MGS0039 significantly attenuated the reduction of spine density in the prelimbic regions of the medial prefrontal cortex, dentate gyrus, and CA3 of the hippocampus, but not infralimbic regions of the medial prefrontal cortex and CA1, in susceptible mice 8 days after a single dose. In contrast, neither drug elicited an effect on altered brain-derived neurotrophic factor-TrkB signaling, GluA1, and postsynaptic density protein 95 levels and did not increase spine density observed in the nucleus accumbens of susceptible mice.

CONCLUSIONS

Similar to ketamine, MGS0039 shows rapid and sustained antidepressant effects in the social defeat stress model. Long-lasting synaptogenesis in the prelimbic regions of medial prefrontal cortex, dentate gyrus, and CA3 might be implicated in this sustained antidepressant effect.

Antibacterial and antibiofilm activities of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) against periodontopathic bacteria

Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are two major omega-3 polyunsaturated fatty acids (n-3 PUFAs) with antimicrobial properties. In this study, we evaluated the potential antibacterial and antibiofilm activities of DHA and EPA against two periodontal pathogens, Porphyromonas gingivalis (P. gingivalis) and Fusobacterium nucleatum (F. nucleatum). MTT assay showed that DHA and EPA still exhibited no cytotoxicity to human oral tissue cells when the concentration came to 100 μM and 200 μM, respectively. Against P. gingivalis, DHA and EPA showed the same minimum inhibitory concentration (MIC) of 12.5 μM, and a respective minimum bactericidal concentration (MBC) of 12.5 μM and 25 μM. However, the MIC and MBC values of DHA or EPA against F. nucleatum were both greater than 100 μM. For early-stage bacteria, DHA or EPA displayed complete inhibition on the planktonic growth and biofilm formation of P. gingivalis from the lowest concentration of 12.5 μM. And the planktonic growth of F. nucleatum was slightly but not completely inhibited by DHA or EPA even at the concentration of 100 μM, however, the biofilm formation of F. nucleatum at 24 h was significantly restrained by 100 μM EPA. For exponential-phase bacteria, 100 μM DHA or EPA completely killed P. gingivalis and significantly decreased the viable counts of F. nucleatum. Meanwhile, the morphology of P. gingivalis was apparently damaged, and the virulence factor gene expression of P. gingivalis and F. nucleatum was strongly downregulated. Besides, the viability and the thickness of mature P. gingivalis biofilm, together with the viability of mature F. nucleatum biofilm were both significantly decreased in the presence of 100 μM DHA or EPA. In conclusion, DHA and EPA possessed antibacterial activities against planktonic and biofilm forms of periodontal pathogens, which suggested that DHA and EPA might be potentially supplementary therapeutic agents for prevention and treatment of periodontal diseases.

Mild hypothermia attenuates post-resuscitation brain injury through a V-ATPase mechanism in a rat model of cardiac arrest

Although therapeutic hypothermia is an effective treatment for post-resuscitation brain injury after cardiac arrest (CA), the underlying mechanism remains unclear. Vacuolar H(+)-ATPase (V-ATPase) plays a key role in cellular adaption to a hypoxic environment. This study sought to evaluate the effect of mild hypothermia on V-ATPase and its involvement in neuroprotection after CA. Male Sprague-Dawley rats were subjected to a 6-min CA, resuscitated successfully, and then assigned to either the normothermia (NT) group or the hypothermia (HT) group. Rats were further divided into 2 subgroups based on the time of euthanasia, either 3 or 24 h after CA (NT-3 h, HT-3 h; NT-24 h, HT-24 h). Mild hypothermia was induced following CA and maintained at 33°C for 2 h. Neurologic deficit scores were used to determine the status of neurological function. Brain specimens were analyzed by TUNEL assay, western blotting, and immunohistochemistry. V-ATPase activity was estimated by subtracting total ATP hydrolysis from the bafilomycin-sensitive activity. Mild hypothermia improved the neurological outcome (HT-24 h: 34.3 ± 16.4 vs NT-24 h: 50.3 ± 17.4) and significantly decreased neurocyte apoptosis 24 h after resuscitation. Mild hypothermia significantly increased V0a1 compared to NT-3 h; V0a1 expression was associated with a decrease in the cleaved caspase 3 expression. These findings suggested that mild hypothermia inhibits CA-induced apoptosis in the hippocampus, which may be associated with reduced V-ATPase impairment. These data provide new insights into the protective effects of hypothermia in vivo.

SP6616 as a new Kv2.1 channel inhibitor efficiently promotes β-cell survival involving both PKC/Erk1/2 and CaM/PI3K/Akt signaling pathways

Kv2.1 as a voltage-gated potassium (Kv) channel subunit has a pivotal role in the regulation of glucose-stimulated insulin secretion (GSIS) and pancreatic β-cell apoptosis, and is believed to be a promising target for anti-diabetic drug discovery, although the mechanism underlying the Kv2.1-mediated β-cell apoptosis is obscure. Here, the small molecular compound, ethyl 5-(3-ethoxy-4-methoxyphenyl)-2-(4-hydroxy-3-methoxybenzylidene)-7-methyl-3-oxo-2,3-dihydro-5H-[1,3]thiazolo[3,2-a]pyrimidine-6-carboxylate (SP6616) was discovered to be a new Kv2.1 inhibitor. It was effective in both promoting GSIS and protecting β cells from apoptosis. Evaluation of SP6616 on either high-fat diet combined with streptozocin-induced type 2 diabetic mice or db/db mice further verified its efficacy in the amelioration of β-cell dysfunction and glucose homeostasis. SP6616 treatment efficiently increased serum insulin level, restored β-cell mass, decreased fasting blood glucose and glycated hemoglobin levels, and improved oral glucose tolerance. Mechanism study indicated that the promotion of SP6616 on β-cell survival was tightly linked to its regulation against both protein kinases C (PKC)/extracellular-regulated protein kinases 1/2 (Erk1/2) and calmodulin(CaM)/phosphatidylinositol 3-kinase(PI3K)/serine/threonine-specific protein kinase (Akt) signaling pathways. To our knowledge, this may be the first report on the underlying pathway responsible for the Kv2.1-mediated β-cell protection. In addition, our study has also highlighted the potential of SP6616 in the treatment of type 2 diabetes.

Effects of escitalopram, R-citalopram, and reboxetine on serum levels of tumor necrosis factor-α, interleukin-10, and depression-like behavior in mice after lipopolysaccharide administration

Inflammation plays a role in the pathophysiology of depression. The purpose of this study is to examine whether the selective serotonin reuptake inhibitor (SSRI) escitalopram, its inactive enantiomer R-citalopram, and selective noradrenaline reuptake inhibitor (NRI) reboxetine, show anti-inflammatory and antidepressant effects in an inflammation-induced model of depression. Pretreatment with escitalopram (1, 3, or 10mg/kg, i.p.) markedly blocked an increase in the serum levels of pro-inflammatory cytokine, tumor necrosis factor-α (TNF-α), after a single administration of lipopolysaccharide (LPS; 0.5mg/kg). Furthermore, escitalopram (3 or 10mg/kg) significantly increased the serum levels of the anti-inflammatory cytokine interleukin-10 (IL-10) by a single administration of LPS. In contrast, pretreatment with R-citalopram (10mg/kg, i.p.) or reboxetine (10mg/kg, i.p.) did not affect the alterations in serum levels of TNF-α and IL-10 after LPS administration. Co-administration of reboxetine with escitalopram did not show anti-inflammatory effects. Pretreatment with escitalopram (10mg/kg) significantly attenuated LPS-induced increase of the immobility time in the tail-suspension test (TST) and forced swimming test (FST). In contrast, pretreatment with R-citalopram (10mg/kg), or reboxetine (10mg/kg) did not alter LPS-induced increase of immobility time of TST and FST. Interestingly, co-administration of reboxetine with escitalopram did not show antidepressant effect in this model. These findings suggest that escitalopram, but not R-citalopram and reboxetine, has anti-inflammatory and antidepressant effects in LPS-treated model of depression, and that reboxetine can antagonize the effects of escitalopram in the inflammation model. Therefore, it is likely that serotonergic system plays a key role in the pathophysiology of inflammation-induced depression.

Comparison of R-ketamine and rapastinel antidepressant effects in the social defeat stress model of depression

RATIONALE

The N-methyl-D-aspartate (NMDA) receptor antagonists, including R-ketamine and rapastinel (formerly GLYX-13), show rapid antidepressant effects in animal models of depression.

OBJECTIVE

We compared the rapid and sustained antidepressant effects of R-ketamine and rapastinel in the social defeat stress model.

RESULTS

In the tail suspension and forced swimming tests, R-ketamine (10 mg/kg, intraperitoneal (i.p.)) or rapastinel (10 mg/kg, i.p.) significantly attenuated the increased immobility time in the susceptible mice, compared with the vehicle-treated group. In the sucrose preference test, both compounds significantly enhanced the reduced preference in susceptible mice 2, 4, or 7 days after a single injection. All mice were sacrificed 8 days after a single injection. Western blot analyses showed that R-ketamine, but not rapastinel, significantly attenuated the reduced brain-derived neurotrophic factor (BDNF)-TrkB signaling, postsynaptic density protein 95 (PSD-95), and GluA1 (a subtype of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor) in the prefrontal cortex, dentate gyrus, and CA3 of the hippocampus in the susceptible mice. In contrast, both compounds had no effect against the increased BDNF-TrkB signaling, PSD-95, and GluA1 seen in the nucleus accumbens of susceptible mice. Moreover, sustained antidepressant effect of R-ketamine (3 mg/kg, intravenous (i.v.)), but not rapastinel (3 mg/kg, i.v.), was detected 7 days after a single dose.

CONCLUSIONS

These results highlight R-ketamine as a longer lasting antidepressant compared with rapastinel in social defeat stress model. It is likely that synaptogenesis including BDNF-TrkB signaling in the prefrontal cortex (PFC) and hippocampus may be required for the mechanisms promoting this sustained antidepressant effect.