Objective To evaluate the effect of dexmedetomidine on the inflammatory responses in brain tissues in septic rats.Methods Seventy-two male Sprague-Dawley rats,aged 10 weeks,weighing 250-280 g,were randomly divided into 4 groups (n =18 each):control group (group C); sepsis group (group lipopolysaccharide (LPS)) ; distilled water group (group DW) and dexmedetomidine group (group D).Sepsis was induced by intraperitoneal injection of LPS 5 mg/kg (dissolved in normal saline 1 ml) in groups LPS,DW and DEX,while normal saline 1 ml was injected intraperitoneally in group C.Distilled water 20 μl was injected into the lateral cerebral ventricle in group DW,while dexmedetomidine 3 μg/kg (dissolved in distilled water 20μl) was injected into the lateral cerebral ventricle in group DEX.Six animals were sacrificed at 1,2 and 6 h after administration and hippocampi were removed for determination of TNF-α and IL-6 contents (by ELISA) and TLR4 mRNA expression in hippocampal tissues (by RT-PCR).Results Compared with group C,TNF-α and IL-6 contents in hippocampus tissues were significantly increased at each time point after administration in group LPS (P ＜ 0.05).Compared with group LPS,no significant change was found in TNF-α and IL-6 contents in hippocampal tissues (P ＞ 0.05),and TLR4 mRNA expression was significantly up-regulated at each time point after administration in group DW (P ＜ 0.05).Compared with group DW,TNF-α and IL-6 contents in hippocampal tissues were significantly decreased at each time point after administration,and TLR4 mRNA expression was significantly up-regulated at 2 and 6 h after administration in group DEX (P ＜ 0.05).Conclusion Dexmedetomidine can reduce inflammatory responses in brain tissues in septic rats via down-regulating TLR-4 mRNA expression.

The effects of carvedilol on cardiomyocyte apoptosis and expression of bcl-2, bax genes following ischemia (0.5 h) and reperfusion (48 h) in vivo and the possible biological mechanism of carvedilol inhibiting cardiomyocyte apoptosis were studied. The left anterior descending artery in Wistar rats were ligated to establish ischemia-reperfusion (I/R) models. The model animals were divided into two groups: I/R group, the model rats not subject to other treatments except ischemia-reperfusion (n = 8); carvedilol-treated group (n = 8), I/R model rats treated with carvedilol. Eight rats in the sham-operated group were subjected to only experimental open operation. The number of apoptotic cardiomyocyte was determined by TUNEL staining. Immunohistochemistry and in situ hybridization histochemistry (ISHH) were used to detect the expression of bcl-2 and bax genes. Image processing system was used to quantitatively dispose the positive metric substances of both immunohistochemistry and ISHH through the average optical density (OD) value. The results showed that the number of the apoptotic cells were 36.18 +/- 9 (I/R group), 0-1 (sham-operated group) and 9.5 +/- 3 (carvedilol-treated group) in each visual field respectively with the difference being very significant among the groups (P < 0.001). The OD values of bcl-2 protein in sham-operated group, I/R group and carvedilol-treated group were 0.14 +/- 0.01, 0.08 +/- 0.02 and 0.15 +/- 0.03, respectively. The OD values of bcl-2 mRNA in sham-operated group, I/R group and carvedilol-treated group were 0.08 +/- 0.01, 0.06 +/- 0.01 and 0.09 +/- 0.01, respectively. There was no significant difference between carvedilol-treated group and I/R group (P > 0.05). The OD values of bax protein in I/R group, sham-operated and carvedilol-treated-treated group were 0.13 +/- 0.02, 0.07 +/- 0.01, 0.06 +/- 0.01, respectively. There was very significant difference between carvedilol-treated group and I/R group (P < 0.01). Bcl-2/bax ratio was 1.07 +/- 0.14 (I/R group), 1.28 +/- 0.16 (sham-operated group), 2.5 +/- 0.26 (carvedilol-treated group) respectively with the difference being very significant between carvedilol-treated group and I/R group (P < 0.05). It was indicated that carvedilol could inhibit cardiomyocyte apoptosis following ischemia and reperfusion, which was related to the increased bcl-2/bax ratio due to inhibition of bax gene expression.
Adrenergic alpha-Antagonists ; pharmacology ; Adrenergic beta-Antagonists ; pharmacology ; Animals ; Apoptosis ; drug effects ; Carbazoles ; pharmacology ; Gene Expression ; Myocardial Ischemia ; genetics ; pathology ; Myocardial Reperfusion Injury ; genetics ; pathology ; Myocytes, Cardiac ; pathology ; Propanolamines ; pharmacology ; Proto-Oncogene Proteins ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; bcl-2-Associated X Protein

OBJECTIVETo establish a method for determining the content of 2,4-toluenediamine, a urinary metabolite of toluene diisocyanate, by gas chromatography.

METHODSUrine samples were collected, and acidification, extraction, derivatization, separation with a capillary column, and detection with an electron capture detector were performed. The target compound was qualified by retention time and quantified by peak area.

RESULTSThe concentration of 2, 4-toluenediamine showed a linear relationship with peak area within 0.0∼40 ng/ml, with a correlation coefficient 0.9995; the limit of detection was 0.44 ng/ml, the lower limit of quantification was 1.47 ng/ml, the relative standard deviation was 1.85%∼4.05%; the recovery rate was 97.98%∼99.28%.

CONCLUSIONThe method has the advantages of high sensitivity and high accuracy and can be used for determination of 2, 4-toluenediamine in urine.

Chromatography, Gas ; methods ; Humans ; Occupational Exposure ; analysis ; Phenylenediamines ; urine

Objective:To explore the postoperative analgesic effect of Dexmedetomidine on elderly patients with colorectal cancer under the guidance of the concept of rapid recovery after surgery.Methods:A total of 230 elderly patients with colorectal cancer who underwent laparoscopic surgery in our hospital from March 2018 to September 2020 were randomly divided into an observation group(receiving Dexmedetomidine auxiliary general anesthesia, n=115)with aged(66.6±4.6)years, male 59, and control group(receiving normal saline auxiliary general anesthesia, n=115), with aged(67.0±4.6)years, male 61.The analgesic effect, hemodyna mic index, postoperativeout of bed activity time, gastrointestinal fuction recovery time postoperative hospital stay and adverse reactions were observed.Results:The pain scores at 4, 8, 12, 24 and 48 h after operation were lower in the observation group than in control group(all P<0.05). The recovery rate of postoperative analgesic drugs was 13.9% in the observation group and 24.3% in the control group( χ2=4.047, P<0.05). Ramesay scores were higher in the observation group than in the control group( P<0.05). Fluctuations of postoperative heart rate and blood pressure were lower in the observation group than in the control group( P<0.05). The total incidence of adverse reactions was lower in the observation group(11.3%)than in the control group(24.3%)( χ2=6.678, P<0.05). Conclusions:Under the guidance of the concept of rapid recovery after surgery, Dexmedetomidine can improve the postoperative analgesic effect in elderly patients with colorectal cancer, reduce the incidence of adverse reactions, and have stable hemodynamics.