Gene expression exhibits temporal and spatial patterns to response environmental changes and growth cycle. Gene expression is under strict control at different levels among which control at transcription level is the predominant mode, especially in prokaryotes. In this review, we summarized the new developments of methods used in transcriptional studies, including modifications and improvements of the classic methods, such as gel-shift assay, DNA foot printing, and in vivo reporter system. In addition, we introduced examples to apply new methods, such as surface plasmon resonance (SPR) and isothermal titration calorimetry (ITC) to characterize protein-DNA, ligand-protein, and ligand-protein-DNA interactions. The collection of these methods and their application could guide and accelerate relevant studies.
Calorimetry ; DNA Footprinting ; Gene Expression ; Ligands ; Proteins ; Surface Plasmon Resonance ; Transcription, Genetic

Bacterial two-hybrid system is a newly developed method for studying protein-protein interactions. However, in our studies of the interaction of regulatory proteins in Streptomyces, it was found that the bacterial two-hybrid system is not sensitive enough by the blue-and-white selection on X-gal plate. To overcome this drawback, the reason of false positive clone was firstly determined, which was the disturbance of other direct or indirect regulation on lacZ promoter. Then the disturbance was diluted by introducing multicopy lacZ promoter, which drive another reporter gene gfp. By such design, the sensitivity of the modified bacterial two-hybrid system was significantly inproved and the two different reporters also help to decrease the rate of the false positive clones. Further the evaluation of the modifiedd bacterial two-hybrid system indicated that the sensitivity was significantly improved.
Bacteria ; Genes, Reporter ; Promoter Regions, Genetic ; Protein Interaction Mapping ; methods ; Two-Hybrid System Techniques

Objective To compare the anesthetic effect of interscalene joint axillary brachial plexus block guided by nerve stimulator or conventional paresthesia in elderly patients with upper extremity surgery.Methods Sixty cases of ASA grade Ⅱ-Ⅲ elderly patients with upper extremity surgery were divided into two groups by random number table.Nerve stimulator group (30 cases) received interscalene joint axillary brachial plexus block guided by nerve stimulator.Paresthesia group (30 cases) received interscalene joint axillary brachial plexus block guided by conventional paresthesia.Both groups used the same local anesthetic:0.375％ ropivacaine,the dosage was 0.4 ml/kg.Anesthetic dose between interscalene and axillary in two groups in half.The operating time,block onset time,duration of analgesia,anesthetic effect [used by visual analogue scale (VAS) scores] and adverse reaction in two groups were observed and recorded.Results The operating time and block onset time in nerve stimulator group were significantly shorter than those in paresthesia group[(5.2 ± 1.7) min vs.(8.6 ± 2.2) min and (19.4 ± 3.2) min vs.(29.0 ± 3.9) min],VAS scores was lower than that in paresthesia group [(0.7 ± 0.4) scores vs.(2.3 ± 0.8) scores],there were significant differences (P ＜ 0.01).There was no significant difference in duration of analgesia between two groups [(12.4 ± 3.6) h vs.(13.1 ± 3.8) h,P ＞0.05].Nerve stimulator group without adverse reactions.Paresthesia group had 5 cases of adverse reactions,including local hematoma in 2 cases,laryngeal recurrent nerve paralysis in 1 case,horner syndrome in 2 cases.Conclusion Interscalene joint axillary brachial plexus block guided by nerve stimulator in elderly patients is accurate positioning,high success rate,good anaesthesia effect,less adverse reaction,and worth promoting in clinical.

Objective To optimize the synthesis process of istradefylline 1 for industrial production.Methods Istrade-fylline was synthesized from dimethyl carbonate and ethylamine through a series reactions including condensation,cycliza-tion,nitrosation,and reduction to produce 1,3-diethyl-5,6-diaminouracil(6),which was subjected to amidation with (E)-3,4-dimethoxycinnamic acid (8),followed by cyclization and methylation reaction.Compound 8 was prepared from veratr-aldehyde and propanedioic acid by Knoevenagel condensation.The structures of intermediate and target compounds were confirmed by MS and 1 H-NMR.Results and Conclusion The quality control points of each key process were optimized so that the total yield was 26.2% and the purity of the product was 99.76%.This improved synthesis method has some advan-tages,such as mild reaction conditions,simple operation,and applicability to industrial production.

Objective To investigate the feasibility of Narcotrend-guided application of small dose of dexmedetomidine ( DEX) for sedation during combined spinal-epidural anesthesia for elderly patients. Methods Fifty cases of ASA II or Ⅲelderly patients were randomly divided into treatment group and control group (25 patients of each group). After combined spinal-epidural anesthesia, both groups received continuous intravenous infusion of DEX, at 0. 4 μg·kg-1 in 10 min, and then the rate was lowered to 0. 4 μg·kg-1 per hour. For the treatment group, infusion rate was adjusted to reach a Narcotrend Index (NTI) of 75-85, and for the control group, infusion rate was adjusted to reach an OAA/S score of level 3-4. MAP, HR, RR, SpO2 , NTI and OAA/S score were recorded at the beginning of DEX treatment ( t0 ) , 10 min ( t1 ) , 20 min ( t2 ) , 30 min ( t3 ) , and 60 min ( t4 ) after the beginning of DEX treatment, and at the end of surgery ( t5 ) . The incidence rates of adverse events including bradycardia, hypotension, low oxygenation, and respiratory depression were also recorded. The patients were followed up until 24 h after surgery to record loss of memory about the surgical events. Results In comparison with t0 , NTI and MAP of both groups significantly decreased at t1-t5(P<0. 01). Comparison between the two groups showed no difference in MAP at each time point, and NTI of treatment group was higher than that of control group at t2-t5(P<0. 05). In comparison with t0, OAA/S of both groups significantly decreased at t1-t5(for t1, P<0. 05;for t2-t5, P<0. 01). Comparison between the two groups showed no difference in OAA/S at each time point (P>0. 05). Follow-up at 24 h after surgery observed total amnesia in 72. 0% of DEX group patients and in 76. 0% of the control group, without significant difference (P>0. 05). Conclusion Sedating elderly patients undergoing spinal-epidural anesthesia with DEX under the guidance of Narcotrend is safe and feasible, and the patients can be sedated properly.

Objective To investigate the anti - stress activity of thymopentin ethyl ester. Methods Anti - stress activity was evaluated by heat stress model and chronic uncontrolled stress model. Heat stress model;of 60 KM mice were divided into six groups. Except the controlled group, the other mice were maintained in 42℃ for 1h. Chronic uncontrolled stress model:of 60 KM mice were divided into six groups. Except the controlled group, the other mice were given three different stimulations once a day for continuous 21 d. The controlled group and model group were injected saline 0.2ml, and the three test groups were respectively injected thympentin ethyl ester at 2mg/kg,0.2mg/kg, 0.02mg/kg subcutaneously. The positive controlled mice were given thymopentin 0.2mg/kg subcutaneously. At the end of the experiment, plasma corticosteroid, IL -2 and SOD were determined according to the kit instructions. Results The activities of thymopentin ethyl ester in suppressed corticosteroid up - regulation and the elevated plasma IL - 2 and SOD level were more significant than those of thymopentin(P

Objective:To investigate the value of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MRI in predicting the pathological grade and early recurrence rate of hepatocellular carcinoma.Methods:The imaging data, pathological data, and follow-up data of 90 patients with hepatocellular carcinoma who underwent Gd-EOB-DTPA-enhanced MRI examination and surgical treatment in People's Hospital of Baise from January 2016 to October 2017 were retrospectively analyzed. The correlation between the signal intensity of contrast-enhanced MRI and postoperative pathological grade was analyzed. Kaplan-Meier survival analysis was performed to investigate the effects of the signal characteristics of hepatobiliary lesions on the early recurrence rate of hepatocellular carcinoma.Results:A total of 59 (65.56%) patients showed low-intensity signals and 31 (34.44%) patients showed mixed-intensity signals. High-intensity signal was not found in any patients. The signal intensity of the hepatobiliary phase was significantly correlated with the pathological grade of the tumor ( χ2 = 2.26, P = 0.040) and tumor size ( t = 3.10, P = 0.033). The early recurrence rate of hepatocellular carcinoma was significantly higher in patients exhibiting mixed-intensity signals than that in patients exhibiting low-intensity signals ( χ2 = 2.25, P = 0.041). Conclusion:Gd-EOB-DTPA-enhanced MRI in the hepatobiliary phase with different signal intensities has the potential to predict the pathological grade and early recurrence rate of hepatocellular carcinoma.

Objective: To explore the correlation between quantitative parameters of dynamic enhanced magnetic resonance imaging (DCE-MRI) and Dukes stage, lymph node metastasis, tumor differentiation degree and molecular biological indicators [Ki67 and human epidermal growth factor receptor 2 (CerbB-2)] of rectal cancer. Methods: This study was a prospective study. From October 2014 to October 2017, 168 cases of rectal cancer patients were selected as the research objects. DCE-MRI was performed preoperatively to obtain the quantitative parameter values of region of interest (ROI) [apparent diffusion coefficient (ADC)_mean, K^trans, V_e, and K_ep] in tumor site. The expression of Ki67 and CerbB-2 were detected by immunohistochemical. Correlations of DCE-MRI quantitative parameter values and rectal cancer Dukes staging, lymph node metastasis, tumor differentiation degree to Ki67 and CerbB-2 expression level were analysised. Results: With the increase of tumor differentiation, ADC_mean was increasing, while K^trans and V_e showed a downward trend, with significant difference (P<0.05). Among them, K^trans and V_e in the high-differentiation group and the medium-differentiation group were significantly lower than those in the low-differentiation group (P<0.05), while there was no statistical significance between the high-differentiation group and the medium-differentiation group (P>0.05). The ADC_mean was statistically significant between different groups (P<0.05), while K_ep was not statistically significant (P>0.05). The ADC_mean of lymph node metastasis group was significantly lower than that of no lymph node metastasis group (P<0.001), while K^trans, V_e and K_ep were significantly higher than that of no lymph node metastasis group (P<0.001). With the increase of Dukes staging in rectal cancer, ADC_mean was decreasing and K^trans was increasing, with statistically significant difference (P<0.001); among which the ADC_mean of Dukes A and B was significantly higher than that of Dukes C and D (P<0.05), and K^trans was significantly lower than that of Dukes C and D (P<0.05). K^trans and K_ep were increased with the increased expression levels of Ki67 and CerbB-2, and the difference between K^trans and K_ep was statistically significant (P<0.05). The ADC_mean decreased with the increase of Ki67 and CerbB-2 expression level, and the difference was statistically significant (P<0.05). Conclusions DCE-MRI quantitatively participates can reflect the biological behavior of rectal cancer, and can be used to evaluate the prognosis of tumors and guide the clinical selection of more appropriate treatment options.

Background: The treatment of trigeminal neuralgia remains a challenging issue.Stem cells from human exfoliated deciduous teeth (SHED) provide optimized therapy for chronic pain. This study aimed to investigate the mechanisms underlying the attenuation of trigeminal neuralgia by SHED. Methods: Trigeminal neuralgia was induced by chronic constriction injury of the infraorbital nerve. The mechanical threshold was assessed after model establishment and local SHED transplantation. Endoplasmic reticulum (ER) morphology and Caspase12 expression in trigeminal ganglion (TG) was evaluated as well. BiP expression was observed in PC12 cells induced by tunicamycin. Results: The local transplantation of SHED could relieve trigeminal neuralgia in rats.Further, transmission electron microscopy revealed swelling of the ER in rats with trigeminal neuralgia. Moreover, SHED inhibited the tunicamycin-induced up-regulated expression of BiP mRNA and protein in vitro. Additionally, SHED decreased the up-regulated expression of Caspase12 mRNA and protein in the TG of rats caused by trigeminal neuralgia after chronic constriction injury of the infraorbital nerve mode. Conclusions This findings demonstrated that SHED could alleviate pain by relieving ER stress which provide potential basic evidence for clinical pain treatment.

Humans ; COVID-19 ; HIV Infections/drug therapy* ; Risk Factors