Studies Related to the Involvement of EsA in Improving Intestinal Inflammation in Acute Pancreatitis via the NF-κB Pathway

Background

Acute pancreatitis (AP) is a clinically frequent acute abdominal condition, which refers to an inflammatory response syndrome of edema, bleeding, and even necrosis caused by abnormal activation of the pancreas's own digestive enzymes. Intestinal damage can occur early in the course of AP and is manifested by impaired intestinal mucosal barrier function, and inflammatory reactions of the intestinal mucosa, among other factors. It can cause translocation of intestinal bacteria and endotoxins, further aggravating the condition of AP. Therefore, actively protecting the intestinal mucosal barrier, controlling the progression of intestinal inflammation, and improving intestinal dynamics in the early stages of AP play an important role in enhancing the prognosis of AP.

Methods

The viability and apoptosis of RAW264.7 cells treated with Esculentoside A (EsA) and/or lipopolysaccharide were detected using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry, respectively. The expression of apoptosis-related proteins and NF-κB signaling pathway-related proteins were detected by western blot (WB). An enzyme-linked immunosorbent assay was used to measure TNF-α and IL-6 secretion.

Results

In vitro experiments demonstrated that EsA not only promoted the apoptosis of inflammatory cells but also reduced the secretion of TNF-α and IL-6 in a dose-dependent manner. Additionally, it inhibited the activation of the NF-κB signaling pathway by decreasing the expression of phosphorylated-p65(p-p65) and elevating the expression of IκBα. Similarly, in vivo experiments using a rat AP model showed that EsA inhibited the expression of p-p65 elevating the expression of IκBα in the intestinal tissues of the rat AP model and promoting the apoptosis of inflammatory cells in the intestinal mucosa in vivo experiments, while improving the pathological outcome of the pancreatic and intestinal tissues.

Conclusion

Our results suggest that EsA can reduce intestinal inflammation in the rat AP model and that EsA may be a candidate for treating intestinal inflammation in AP and further arresting AP progression.

[IL-6 inhibits colonic longitudinal muscle contraction by inactivating L-type calcium channel in rats with pancreatitis]

The aim of this study was to investigate the effect of interleukin 6 (IL-6) on the contraction of colon longitudinal muscle strips in rats with acute pancreatitis (AP) and its underlying mechanism. Rat AP model was established by combined injection (i. p.) of ceruletide and lipopolysaccharide. The effect of IL-6 on spontaneous contraction of longitudinal smooth muscle strips of rat colon was observed by biological function experiment system. The level of serum IL-6 was detected by ELISA, the expression and distribution of IL-6 in colon were observed by histochemical staining, and the effect of IL-6 on L-type calcium channel in colon smooth muscle cells was observed by whole cell patch clamp technique. The results showed that, compared with the control group, AP group exhibited reduced contractile amplitude and longer contraction cycle of colon smooth muscle strips. IL-6 prolonged the contraction cycle of colon smooth muscle strips, but did not affect their spontaneous contraction amplitude. Serum IL-6 concentration in AP group was significantly higher than that in control group (P > 0.05). IL-6 was diffusely distributed in the colon of the control group, but the expression of IL-6 was significantly up-regulated in the colon gland, mucosa and submucosa of the AP group. IL-6 significantly decreased the peak current density of L-type calcium channel in rat colon smooth muscle cells. These results suggest that the colon motility of AP rats is weakened, and the mechanism may be that up-regulated IL-6 inactivates L-type voltage-dependent calcium channels, and then inhibits the contraction of colon longitudinal smooth muscle.

Causes of ozone pollution in summer in Wuhan, Central China

In August 2016, continuous measurements of volatile organic compounds (VOCs) and trace gases were conducted at an urban site in Wuhan. Four high-ozone (O₃) days and twenty-seven non-high-O₃ days were identified according to the China's National Standard Level II (∼100 ppbv). The occurrence of high-O₃ days was accompanied by tropical cyclones. Much higher concentrations of VOCs and carbon monoxide (CO) were observed on the high-O₃ days (p < 0.01). Model simulations revealed that vehicle exhausts were the dominant sources of VOCs, contributing 45.4 ± 5.2% and 37.3 ± 2.9% during high-O₃ and non-high-O₃ days, respectively. Both vehicle exhausts and stationary combustion made significantly larger contributions to O₃ production on high-O₃ days (p < 0.01). Analysis using a chemical transport model found that local photochemical formation accounted for 74.7 ± 5.8% of the daytime O₃, around twice the regional transport (32.2 ± 5.4%), while the nighttime O₃ was mainly attributable to regional transport (59.1 ± 9.9%). The local O₃ formation was generally limited by VOCs in urban Wuhan. To effectively control O₃ pollution, the reduction ratio of VOCs to NO_x concentrations should not be lower than 0.73, and the most efficient O₃ abatement could be achieved by reducing VOCs from vehicle exhausts. This study contributes to the worldwide database of O₃-VOC-NO_x sensitivity research. Its findings will be helpful in formulating and implementing emission control strategies for dealing with O₃ pollution in Wuhan.

A meta-analysis and systematic review of prophylactic endoscopic treatments for postpolypectomy bleeding

PURPOSE

The aim of this meta-analysis and systematic review was to determine whether bleeding prophylaxis benefits patients after colonoscopic polypectomy.

METHODS

A systematic review of the literature was performed to find prospective randomized controlled trials of postpolypectomy hemorrhage prophylaxis. Studies were selected according to specific criteria and analyzed to generate pooled data.

RESULTS

Eight studies encompassing 2,595 polyps met the criteria for the meta-analysis. The rate of early bleeding was significantly decreased relative to the control when a single prophylactic technique was used [2.58% vs. 8.15%, OR = 0.34 (95% CI, 0.20-0.58), P < 0.0001]. The use of multiple prophylactic techniques resulted in a lower early postpolypectomy hemorrhage rate compared with the use of a single prophylactic technique [0% vs. 8.41%, OR = 0.12 (95% CI, 0.03-0.47), P = 0.002]. The late bleeding rate did not differ significantly between the monotherapy and control groups [0.61% vs. 1.39%, OR = 0.37 (95% CI, 0.11-1.28), P = 0.12], and the use of combined preventative techniques did not significantly decrease the late postpolypectomy bleeding (PPB) rate compared with use of a single prophylactic method [1.43% vs. 2.05%, OR = 0.70 (95% CI, 0.32-1.55), P = 0.38].

CONCLUSION

Prophylactic endoscopic treatments are effective at reducing early PPB after colonoscopic polypectomy. However, patients with late PPB may not benefit from bleeding prophylaxis.

Effects of patient-controlled upper and lower epidural analgesias on postoperative respiratory and circulatory function

OBJECTIVE: To compare the effects of patient-controlled high thoracic epidural analgesia (PCHEA) and low thoracic epidural analgesia (PCLEA) on respiratory and circulatory functions after operation. METHODS: Thirty-six patients were divided into 2 groups with 18 in each, and one group (Group H) received PCHEA during thoracic operations and the other (Group L) received PCLEA during abdominal operations. Postoperative patient-controlled analgesia (PCA) was performed in all the patients with 0.125% bupivacaine and 0.01% morphine delivered through the same epidural space for PCHEA or PCLEA. RESULTS: Postoperative analgesia did not produce significant differences in the respiration rate (Rr), tidal volume (Vt), vital capacity (VC) and oxygen saturation (SpO2) between the groups, but in both groups, Vt and VC were significantly improved compared with those before starting patient-controlled epidural analgesia (PECA) (P<0.01). In group H, its effects on systolic and diastolic blood pressure and heart rate were more obvious than in group L (P<0.05), and both groups showed these improvements after PCA started(P<0.01). CONCLUSION: PCHEA shows more marked effects on the respiratory and circulatory functions of the patients, which may mainly result from its blocking the cardiac sympathetic nerves. PCEA is able to improve postoperative respiratory function but both PCHEA and PCLEA necessitate individual-based adjustment of the PCA pump for the safety of the patient.

[Anesthetic management during resection of intratracheal tumor: report of 23 cases]

OBJECTIVE

To summarize our experience in anaesthetic management during the resection of intratracheal tumor.

METHODS

A retrospective analysis of the anaesthetic management was conducted in 23 cases of intratracheal tumor resection. The anaesthetic methods were determined according to the location of tumor, the degree of tracheal obstruction and the surgical procedures.

RESULTS

No severe complications occurred in relation to the anesthetic procedures. During the operation, the saturation of pulse oxygen (SpO(2)) transiently decreased to below 90 % in 5 cases (21.7 %) but recovered to normal level by aspiration of airway secretions and/or lung inflation. Seventeen patients (73.9 %) were extubated after the operation and returned to the ward safely, while another 6 (26.1 %) were sent to intensive care unit and extubated within 24 h.

CONCLUSION

Case-specific anaesthetic plan is necessary before the operation, and it is crucial to maintain good ventilation without interfering with the surgical procedures during the operation.

Effect of patient-controlled epidural analgesia for pain relief after thymectomy in patients with myasthenia gravis

OBJECTIVE

To evaluate the effect of patient-controlled epidural analgesia (PCEA) with ropivacaine or bupivacaine in relieving pain after thymectomy in patients with myasthenia gravis.

METHODS

Twenty adult ASA I-II patients with myasthenia gravis were randomized to receive either 0.125% ropivacaine (Group R, n=10) or 0.125% bupivacaine (Group B, n=10) with a PCEA device after transsternal thymectomy. PCEA (continuous infusion at 1 ml/h, bolus dose of 4 ml and lockout time of 30 min) was implemented via an epidural catheter inserted in the T3-4 intervertebral space. The vital signs and visual analogue scale (VAS), together with cumulative consumption (CC) of ropivacaine or bupivacaine were recorded within 48 h postoperatively.

RESULTS

The vital signs, including systolic and diastolic blood pressure, heart rate, SpO2, pH and PaCO2, did not show any significant differences between the 2 groups. The CC of the local anesthetic was significantly higher in group R than that in group B at 24 and 48 h postoperatively, but VAS were not significantly different between the 2 groups which was less than 4 in both groups.

CONCLUSIONS

PCEA with low concentration of ropivacaine or bupivacaine may provide effective and safe analgesia after transsternal thymectomy.

[Effects of intraperitoneal CO2 insufflation on hemodynamics and oxygen consumption during intravenous propofol anesthesia combined with epidural block]

OBJECTIVE

To investigate the effects of intraperitoneal CO2 insufflation on the hemodynamics, oxygen consumption (VO2) and carbon dioxide production (VCO2) during intravenous anesthesia with propofol in combination with epidural block.

METHODS

Intratracheal intubation was performed after rapid induction of anesthesia and mechanical ventilation was given. Maintenance of anesthesia was achieved using continuous intravenous propofol infusion (2 mg/kg/h) ?N2O inhalation and intermittent epidural administration. Indices of hemodynamics and respiratory function were collected 5 min before induction, 1 min before CO2 insufflation, and 5, 10, 20, 30, 40, 50, 60 min after the start of insufflation and 5 min after the termination of insufflation.

RESULTS

The mean arterial pressure (MAP), heart rate (HR), end-tidal PCO2 (P(ET)CO2), VO2 and VCO2 1 min before insufflation were markedly reduced(P<0.01), compared with those recorded before induction. MAP and HR did not undergo any conspicuous changes during CO2 insufflation and 5 min after insufflation termination. Compared with that 1 min before insufflation, PETCO2 was significantly increased 20 min after the start of insufflation (P<0.01), and subsequently carried on the increase though of a lesser scale. VO2 and VCO2 gradually rose after the start of insufflation, and VO2 presented a significantly elevation (P<0.01) 10 min after the insufflation while VCO2 did not show this marked increase(P<0.05) till 20 min after the insufflation in comparison with the levels before insufflation. Subsequently, VO2 continued to rise and VCO2 also retained the increase but of smaller magnitude.

CONCLUSION

Intravenous propofol anesthesia combined with epidural block assisted by well-managed excessive ventilation before insufflation can alleviate the adverse effects of CO2 insufflation on respiratory and circulatory systems.

Gene construction, expression, and characterization of double-copy truncated form of human insulin-like growth factor I

AIM

To increase the production of recombinant truncated form of insulin-like growth factor I [des(1-3)IGF-I], purify the expressed product, and compare its bioactivity with that of standard IGF-I.

METHODS

The second copy of des(1-3)IGF-I gene was inserted into the previously constructed pExSec1/IGF-I to form a pExSec1/2(IGF-I) expression plasmid, then the plasmid was transformed into a protease-deficient E coli strain BL21(DE3). The engineered bacteria were cultured and induced by IPTG at 12 degrees C. The expressed product was purified through ultrafiltration and Sephadex G-50 gelfiltration. The bioactivity of the preliminarily purified protein was tested by MTT method and compared with standard IGF-I.

RESULTS

The amount of des(1-3)IGF-I expressed by pExSec1/2(IGF-I) reached up to 20 % of the total soluble bacterial protein, which was higher than the amount (12 %) expressed by a single copy of pExSec1/IGF-I gene. The purity of recombinant des(1-3)IGF-I reached 49 % and 82 % after ultrafiltration and gelfiltration. The bioactivity of des(1-3)IGF-I after gelfiltration was about 77 % of standard IGF-I at the same concentration.

CONCLUSION

The yield of recombinant des(1-3)IGF-I was increased about 8 % by construction of expression plasmid with two copies of des(1-3)IGF-I gene compared with only one copy of gene, and preliminarily purified des(1-3)IGF-I showed about 77 % bioactivity compared with standard IGF-I.

Life events, frontal electroencephalogram laterality, and functional immune status after acute psychological stressors in adolescents

OBJECTIVE

Past studies have found that environmental stress affects cellular immune function and that extensive variability exists in the magnitude and direction of stress-induced immune changes. Past research also suggests that individuals with greater right, relative to left, resting frontal electroencephalogram (EEG) activation perceive environmental stress as more aversive and have lower baseline cellular immune function. In this study, we examined environmental stressors, resting frontal EEG laterality, and immune responses to short-term psychological stressors in adolescent boys.

METHODS

A sample of twenty-four 14-16 year old right-handed boys underwent a recording of resting EEG and collections of blood taken before and after a laboratory protocol designed to induce psychological stress. Blood samples were used to measure changes in mitogen lymphoproliferative responses, natural killer (NK) cell activity, and T-cell phenotypic subsets. Life events were measured using self-report questionnaires.

RESULTS

Life events and frontal laterality showed a first order interaction in predicting changes in lymphocyte proliferation to tetanus toxoid (R2 increment = .26, p < .01) and pokeweed mitogen (R2 increment = .25, p < .02). The interaction also predicted changes in NK activity (R2 increment = .24, p < .02).

CONCLUSIONS

Changes in lymphocyte proliferation and NK activity were associated with negative life events only among individuals with greater left frontal cortical activation. Our results suggest that recent psychosocial stress and individual differences in resting frontal cortical activation are together linked to immunologic responses to acute psychological stressors.

Life events, cardiovascular reactivity, and risk behavior in adolescent boys

BACKGROUND

Risk behavior contributes to injuries, one of the most important sources of morbidity and mortality in adolescents. Although research has shown that environmental stress makes adolescents more likely to engage in risk behavior and to sustain injuries, the magnitude of these associations has been small. Little is known about the role of individual differences in psychobiologic reactivity to stress in moderating the impact of stressful events. In this study, we examined associations among environmental stressors, cardiovascular reactivity to stress, and the level of risk behavior in adolescent boys.

METHODS

Twenty-four 14- to 16-year-old boys underwent a laboratory protocol designed to measure responses to psychologically and physically stressful tasks. Changes in heart rate and mean arterial blood pressure were measured serially at standard points in the protocol, and levels of positive and negative life events and recent risk behavior were measured using self-report questionnaires.

RESULTS

Neither life events nor cardiovascular reactivity were independently associated with risk behavior. Positive life events and mean arterial blood pressure reactivity significantly interacted, however, in predicting risk behavior (R2 increment = .25). Boys with high reactivity who reported numerous positive life events engaged in markedly less risk behavior than their peers.

CONCLUSION

We conclude that adolescents with exaggerated cardiovascular responses to laboratory stressors are associated with less risk behavior in a setting of positive life circumstances. This result suggests that reactivity may exert protective, rather than harmful, influences in some environments.

The psychobiology of childhood stress

Recent psychobiologic research has provided new insights into the interplay between constitutional and environmental etiologies in stress-induced childhood illness. Individual differences in both psychobiologic reactivity and physiologic self-regulation may substantially influence a child's internal stress responses. In addition, the physiologic consequences of a given environmental stressor may depend critically on the developmental stage in which the stressor occurs. Behavioral changes associated with early exposures to stressors may be linked to alterations in central nervous system monoamine production and metabolism. Evidence for developmental and psychobiologic changes in response to very early, even prenatal, stressors suggests that environmental and genetic contributions to stress response profiles may ultimately be difficult to disentangle.

[Studies of midazolam, diazepam and thiopentone on respiratory and cardiovascular function during induction anesthesia]

In this study, the effects of midazolam (M), diazepam (D) and thiopentone (T) on respiratory and cardiovascular systems were compared. The patients were randomly divided into 6 groups, besides minute ventilatory volume (MV), onset of induction and cardiovascular changes were also observed. Induction was performed by a bolus injection of one of the following: midazolam (0.3 mg/kg), diazepam (0.3 mg/kg) or thiopentone (5 mg/kg). Five minutes later, 5 micrograms/kg fentanyl and 1.5-2.0 mg/kg succinylcholine were administered. The results showed that: (1) Inhibitory effect on MV was not prominent and similar after use of midazolam and diazepam but was remarkable after thiopental; (2) As for the onset, midazolam was faster than diazepam but slower than thiopentone; (3) Hemodynamic changes of midazolam, diazepam and thiopentone were similar, however during intubation, cardiovascular response was the least in midazolam, diazepam the intermediate and thiopentone the most significant. We conclude that midazolam is a water-soluble, safe and effective inductive anesthetic with its short eliminated half-life period, and much lesser venous irritation, and it is certainly superior to both diazepam and thiopentone.