[Effect of positive end-expiratory pressure on the cross-sectional area of the internal jugular vein and anatomic relationship between the internal jugular vein and the carotid artery in general anaesthesia of laryngeal mask airway]

Objective: To investigate the effect of positive end-expiratory pressure(PEEP) on the cross-sectional area (CSA) of the internal jugular vein (IJV) and anatomic relationship between the IJV and the common carotid artery (CCA) in general anaesthesia of laryngeal mask airway(LMA). Methods: Sixty American Society of Anesthesiologists (ASA) Ⅰ or Ⅱ grade patients undergoing elective operation received general anaesthesia using LMA from May to November 2017, aged 20-65, were included in this study and randomly divided into 4 groups: group P0 (PEEP: 0 cmH(2)O), group P5 (PEEP: 5 cmH(2)O), group P10 (PEEP: 10 cmH(2)O), group P15 (PEEP: 15 cmH(2)O). Following the induction of anesthesia, LMA was inserted, and mechanical ventilation was started while the right cervical vessels was imaged by ultrasonography after applying 4 different PEEPs in random order. Measurements were made after 1 min in each PEEP. The CSA, transverse diameter (TD), anteroposterior diameters (AD) of the IJV and the diameter, overlap distance and overlap index of CCA was measured. The arterial blood pressure, heart rate, and vasoactive drugs used were also recorded. Results: The CSA of group P0, P10 and P15 was (1.36±0.55), (1.80±0.54), (2.02±0.58) cm(2). The TD was (1.31±0.33), (1.61±0.49), (1.74±0.53) cm. The AD was (1.12±0.20), (1.33±0.30), (1.46±0.32) cm. Compared to group P0, the CSA, TD and AD of IJV in group P10 and P15 were significantly increased (P0/P10: t=7.81, 3.81, 4.30, all P<0.01; P0/P15: t=11.68, 5.40, 6.96, all P<0.01). There was no significant difference in the AD and TD of IJV between group P10 and P15 (all P>0.05), while the CSA of group P15 was bigger than that of group P10 (t=2.17, P<0.05). The overlap distance of group P0, P10 and P15 was (0.51±0.12), (0.62±0.16), (0.66±0.15) cm. The overlap index was (76.80±20.03)%, (91.10±26.13)%, (96.21±25.36)%. Compared to group P0, the overlap distance and overlap index in group P10 and P15 were significantly increased (P0/P10: t=4.49, 3.41, both P<0.01; P0/P15: t=5.91, 4.63, both P<0.01). There was no significant changes in the overlap distance and overlap index between group P10 and P15 (all P>0.05). The MAP of group P15 was lower than that of group P10 [(73.35±9.73 )vs (67.58±12.58) mmHg, t=2.745, P<0.05]. No patients were given atropine or norepinephrine. Conclusions: The application of PEEP effectively increases the CSA of IJV in general anaesthesia of LMA. At the same time, it also lead to higher overlap index between the IJV and CCA.Ten cmH(2)O PEEP provides the best balance between the increase of CSA and the stability of haemodynamics.

New Insights on the Structure of Electrochemically Deposited Lithium Metal and Its Solid Electrolyte Interphases via Cryogenic TEM

Lithium metal has been considered the "holy grail" anode material for rechargeable batteries despite the fact that its dendritic growth and low Coulombic efficiency (CE) have crippled its practical use for decades. Its high chemical reactivity and low stability make it difficult to explore the intrinsic chemical and physical properties of the electrochemically deposited lithium (EDLi) and its accompanying solid electrolyte interphase (SEI). To prevent the dendritic growth and enhance the electrochemical reversibility, it is crucial to understand the nano- and mesostructures of EDLi. However, Li metal is very sensitive to beam damage and has low contrast for commonly used characterization techniques such as electron microscopy. Inspired by biological imaging techniques, this work demonstrates the power of cryogenic (cryo)-electron microscopy to reveal the detailed structure of EDLi and the SEI composition at the nanoscale while minimizing beam damage during imaging. Surprisingly, the results show that the nucleation-dominated EDLi (5 min at 0.5 mA cm^-2) is amorphous, while there is some crystalline LiF present in the SEI. The EDLi grown from various electrolytes with different additives exhibits distinctive surface properties. Consequently, these results highlight the importance of the SEI and its relationship with the CE. Our findings not only illustrate the capabilities of cryogenic microscopy for beam (thermal)-sensitive materials but also yield crucial structural information on the EDLi evolution with and without electrolyte additives.

[A comparison between the revision of Atlanta classification and determinant-based classification in acute pancreatitis]

Objective: To compare the performance of the revision of Atlanta classification (RAC) and determinant-based classification (DBC) in acute pancreatitis. Methods: Consecutive patients with acute pancreatitis admitted to a single center from January 2001 to January 2015 were retrospectively analyzed. Patients were classified into mild, moderately severe and severe categories based on RAC and were simultaneously classified into mild, moderate, severe and critical grades according to DBC. Disease severity and clinical outcomes were compared between subgroups. The receiver operating curve (ROC) was used to compare the utility of RAC and DBC by calculating the area under curve (AUC). Results: Among 1 120 patients enrolled, organ failure occurred in 343 patients (30.6%) and infected necrosis in 74 patients(6.6%). A total of 63 patients (5.6%) died. Statistically significant difference of disease severity and outcomes was observed between all the subgroups in RAC and DBC (P<0.001). The category of critical acute pancreatitis (with both persistent organ failure and infected necrosis) had the most severe clinical course and the highest mortality (19/31, 61.3%). DBC had a larger AUC (0.73, 95%CI 0.69-0.78) than RAC (0.68, 95%CI 0.65-0.73) in classifying ICU admissions (P=0.031), but both were similar in predicting mortality(P=0.372) and prolonged ICU stay (P=0.266). Conclusions: DBC and RAC perform comparably well in categorizing patients with acute pancreatitis regarding disease severity and clinical outcome. DBC is slightly better than RAC in predicting prolonged hospital stay. Persistent organ failure and infected necrosis are risk factors for poor prognosis and presence of both is associated with the most dismal outcome.

Application of data mining techniques to explore predictors of upper urinary tract damage in patients with neurogenic bladder

This study proposed a decision tree model to screen upper urinary tract damage (UUTD) for patients with neurogenic bladder (NGB). Thirty-four NGB patients with UUTD were recruited in the case group, while 78 without UUTD were included in the control group. A decision tree method, classification and regression tree (CART), was then applied to develop the model in which UUTD was used as a dependent variable and history of urinary tract infections, bladder management, conservative treatment, and urodynamic findings were used as independent variables. The urethra function factor was found to be the primary screening information of patients and treated as the root node of the tree; Pabd max (maximum abdominal pressure, >14 cmH₂O), Pves max (maximum intravesical pressure, ≤89 cmH₂O), and gender (female) were also variables associated with UUTD. The accuracy of the proposed model was 84.8%, and the area under curve was 0.901 (95%CI=0.844-0.958), suggesting that the decision tree model might provide a new and convenient way to screen UUTD for NGB patients in both undeveloped and developing areas.

Effects of Teriparatide on Joint Erosions in Rheumatoid Arthritis: A Randomized Controlled Trial

OBJECTIVE

Articular erosions correlate with disability in rheumatoid arthritis (RA). Biologic agents reduce erosion progression in RA, but erosion healing occurs infrequently. This study was undertaken to assess the effects of the anabolic agent teriparatide on joint erosion volume in RA patients treated with a tumor necrosis factor inhibitor (TNFi).

METHODS

We conducted a randomized controlled trial in 24 patients with erosive RA, osteopenia, and disease activity controlled by TNFi treatment for at least 3 months. Half were randomized to receive teriparatide for 1 year and the others constituted a wait-list control group. Subjects and primary rheumatologists were not blinded with regard to treatment assignment, but all outcomes were assessed in a blinded manner. The primary outcome measure was change in erosion volume determined by computed tomography at 6 anatomic sites. Significance within each hand and anatomic site was based on a 2-tailed test, with P values less than 0.05 considered significant.

RESULTS

Baseline characteristics of the treatment groups were well balanced. After 52 weeks, the median change in erosion volume in the teriparatide group was -0.4 mm³ (interquartile range [IQR] -34.5, 29.6) and did not differ significantly from that in controls (median change +9.1 mm³ [IQR -29.6, 26.4]) (P = 0.28). No significant difference in change in erosion volume was noted at the radius, ulna, or metacarpophalangeal joints. Bone mineral density improved at the femoral neck and lumbar spine in the teriparatide group.

CONCLUSION

Our findings indicate that teriparatide treatment for 1 year does not significantly reduce erosion volume in the hands or wrists of patients with established RA with disease activity controlled by TNFi treatment.

Influence of VEGF/BMP-2 on the proliferation and osteogenetic differentiation of rat bone mesenchymal stem cells on PLGA/gelatin composite scaffold

OBJECTIVE

To investigate the influence of VEGF/BMP-2 on the proliferation and osteogenic differentiation of rat bone mesenchymal stem cells BMSCs) on PLGA/gelatin composite scaffold.

MATERIALS AND METHODS

Randomly-oriented nanofibers with different ratios of Poly Lactic-co-Glycolic Acid (PLGA)/gelatin were produced through electrospinning. The mixture of nanofibers and BMSCs was pipetted onto the surface of the scaffolds, and BMSCs/PLGA/gelatin composite was obtained. The surface morphology, chemical structure, hydrophilicity and mechanical property of PLGA/gelatin nanofibers were revealed by scanning electron microscope. In vitro release kinetics of bone morphogenetic protein (BMP-2) and vascular endothelial growth factor (VEGF) were studied using ELISA kits. The cell adhesion, growth and proliferation of BMSCs on scaffolds were observed by scanning electron microscopy. The CCK-8 assay was used to evaluate the effects of VEGF/BMP-2 slow release system on the proliferation of BMSCs on scaffolds. RT-PCR was used to examine the activities of alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX-2), and osteocalcin (OCN).

RESULTS

In each group of cells in the in-vitro experiment, through electron microscope scanning, fiber scaffolds were interconnected three-dimensional reticular structure, BMSCs firmly attached to the fiber surface and internal stent, cells experienced a long spindle, polygon change, and branch-like protrusions on the cell surface were connected. Under the electron microscope, cell proliferation curve and osteogenesis markers (ALP, RUNX-2, OCN) expression in the dual factor group on cell adhesion, proliferation and differentiation were much better than those of blank control group and single factor groups.

CONCLUSIONS

In the successfully constructed gelatin/PLGA nanofiber scaffold, VEGF and BMP-2 can be sequentially released, during which VEGF and BMP-2 can promote the adhesion, proliferation, and differentiation of BMSCs.

NF-κB/P65 signaling pathway: a potential therapeutic target in postoperative cognitive dysfunction after sevoflurane anesthesia

OBJECTIVE

This study aimed to explore the role of NF-κB/P65 signaling pathway in postoperative cognitive dysfunction (POCD) after sevoflurane anesthesia.

MATERIALS AND METHODS

A total of 120 male Sprague-Dawley (SD) rats were selected and assigned into five groups (24 rats in each group): the control, sevoflurane, sevoflurane + splenectomy, pyrrolidine dithiocarbamate (PDTC, a specific inhibitor of NF-κB), and sevoflurane + splenectomy + PDTC groups. Electrocardiogram (ECoG) and behavior changes of rats were monitored before and after anesthesia/operation. Ionized calcium-binding adapter molecules 1 (Iba-1) in the hippocampal zones were observed by immunofluorescence staining. Blood-brain barrier (BBB) permeability was determined by immunohistochemistry. The mRNA and protein expressions of NF-κB/P65 signaling pathway-related proteins and inflammatory cytokines were detected by qRT-PCR assay and Western blotting.

RESULTS

During the anesthesia/operation, the vital signs of rats were stable, but the ECoG in the sevoflurane and sevoflurane + splenectomy groups mainly presented slow waves. The ECoG arousal response in the sevoflurane + splenectomy + PDTC group was observed. At 24 h after the anesthesia/operation, the expressions of NF-κB and P65 in the hippocampal zone, the expressions of IκBα and inflammatory cytokines (IL-1β, IL-6 and TNF-α), the expression of Iba-1 in rat hippocampal dentate gyrus (DG) zone and CA3 zone, and the permeability of BBB were significantly increased and the behavior of rats changed dramatically (all p < 0.05), while PDTC treatments could eliminate these changes induced by the anesthesia/operation (all p < 0.05). No changes were observed in the expressions of NF-κB, P65, IκBα, Iba-1 and inflammatory cytokines (IL-1β, IL-6 and TNF-α), and the permeability of BBB and the behavior of rats in the sevoflurane and the PDTC groups (all p > 0.05).

CONCLUSIONS

These results suggest that the inhibition of NF-κB/P65 signaling pathway may relieve POCD after sevoflurane anesthesia.

CD39 overexpression does not attenuate renal fibrosis in the unilateral ureteric obstructive model of chronic kidney disease

Chronic kidney disease has multiple etiologies, but its single, hallmark lesion is renal fibrosis. CD39 is a key purinergic enzyme in the hydrolysis of ATP and increased CD39 activity on regulatory T cells (Treg) is protective in adriamycin-induced renal fibrosis. We examined the effect of overexpression of human CD39 on the development of renal fibrosis in the unilateral ureteric obstructive (UUO) model, a model widely used to study the molecular and cellular factors involved in renal fibrosis. Mice overexpressing human CD39 (CD39Tg) and their wild-type (WT) littermates were subjected to UUO; renal histology and messenger RNA (mRNA) levels of adenosine receptors and markers of renal fibrosis were examined up to 14 days after UUO. There were no differences between CD39Tg mice and WT mice in the development of renal fibrosis at days 3, 7, and 14 of UUO. Relative mRNA expression of the adenosine A_2A receptor and endothelin-1 were higher in CD39Tg than WT mice at day 7 post UUO, but there were no differences in markers of fibrosis. We conclude that human CD39 overexpression does not attenuate the development of renal fibrosis in the UUO model. The lack of protection by CD39 overexpression in the UUO model is multifactorial due to the different effects of adenosinergic receptors on the development of renal fibrosis.