Noradrenaline modulates the spontaneous firing activities of Purkinje cells via α2-adrenergic receptor in mouse cerebellar cortex / 生理学报

Cerebellar Purkinje cells (PCs) exhibit two types of discharge activities: simple spike (SS) and complex spike (CS). Previous studies found that noradrenaline (NA) can inhibit CS and bidirectionally regulate SS, but the enhancement of NA on SS is overwhelmed by the strong inhibition of excitatory molecular layer interneurons. However, the mechanism underlying the effect of NA on SS discharge frequency is not clear. Therefore, in the present study, we examined the mechanism underlying the increasing effect of NA on SS firing of PC in mouse cerebellar cortex in vivo and in cerebellar slice by cell-attached and whole-cell recording technique and pharmacological methods. GABAA receptor was blocked by 100 µmol/L picrotoxin in the whole process. In vivo results showed that NA significantly reduced the number of spikelets of spontaneous CS and enhanced the discharge frequency of SS, but did not affect the discharge frequency of CS. In vitro experiments showed that NA reduced the number of CS spikelets and after hyperpolarization potential (AHP) induced by electrical stimulation, and increased the discharge frequency of SS. NA also reduced the amplitude of excitatory postsynaptic current (EPSC) of parallel fiber (PF)-PC and significantly increased the paired-pulse ratio (PPR). Application of yohimbine, an antagonist of α2-adrenergic receptor (AR), completely eliminated the enhancing effect of NA on SS. The α2-AR agonist, UK14304, also increased the frequency of SS. The β-AR blocker, propranolol, did not affect the effects of NA on PC. These results suggest that in the absence of GABAA receptors, NA could attenuate the synaptic transmission of climbing fiber (CF)-PC via activating α2-AR, inhibit CS activity and reduce AHP, thus enhancing the SS discharge frequency of PC. This result suggests that NA neurons of locus coeruleus can finely regulate PC signal output by regulating CF-PC synaptic transmission.

Analysis of Radial Peripapillary Capillary Density in Patients with Bietti Crystalline Dystrophy by Optical Coherence Tomography Angiography / 生物医学与环境科学（英文）

OBJECTIVE@#We wanted to investigate the radial peripapillary capillary (RPC) network in patients with Bietti crystalline dystrophy (BCD).@*METHODS@#We compared RPC densities in the disk and different peripapillary regions, obtained using optical coherence tomography angiography in 22 patients with BCD (37 eyes) and 22 healthy subjects (37 eyes). The BCD group was then divided into Stage 2 and Stage 3 subgroups based on Yuzawa staging, comparing the RPC densities of the two.@*RESULTS@#The disk area RPC density was 38.8% ± 6.3% in the BCD group and 49.2% ± 6.1% in the control group ( P < 0.001), and peripapillary region RPC density was significantly lower in the BCD group than in the control group (49.1% ± 4.7% and 54.1% ± 3.0%, respectively, P < 0.001). There were no significant RPC density differences between the tempo quadrant and inside disk of Stages 2 and 3 subgroups; the other areas showed a significantly lower RPC density in Stage 3 than in Stage 2 BCD.@*CONCLUSION@#The BCD group RPC density was significantly lower than the control group. The reduction of RPC density in the tempo quadrant occurred mainly in the Stage 1 BCD. In contrast, the reduction of RPC density in superior, inferior, and nasal quadrants occurred mainly in Stage 2.

Clinical application evaluation of clinical practice guideline on traditional Chinese medicine therapy alone or combined with antibiotics for uncomplicated lower urinary tract infection / 中国中药杂志

A questionnaire survey of 1 000 clinicians having experience in treating uncomplicated lower urinary tract infections from different levels of hospitals was conducted to mainly evaluate the applicability and effectiveness of clinical application of clinical practice guideline on traditional Chinese medicine therapy alone or combined with antibiotics for uncomplicated lower urinary tract infection(hereinafter referred to as Guideline). The research was conducted with the three-level quality control strictly throughout the process, and the data was real and reliable. The survey's results showed that: most clinicians considered that the Guideline had good clinical applicability. The availability and price of the recommended medicine were moderate. Traditional Chinese medicine had obvious features and advantages in treating lower urinary tract infection for it could reduce the usage of antibiotics and shorten the course of antibiotic application. In the recommendation section, clinicians proposed increasing medication guidance, updating the Guideline timely, as well as increasing treating methods and techniques, strengthen propaganda and promotion, and improve the use of evidence-based methods. In the evaluation of effectiveness, the majority of clinicians agreed that the definition in both traditional Chinese medicine (TCM) and Western medicine and differential diagnosis in the Guideline were accurately described and the basic principle of treatment as well as the treating method of TCM were recommended appropriately. The TCM formulas and Chinese patent medicine had good effect. Some clinicians suggested refining the syndrome differentiation of stranguria. Some clinicians considered that the formulas and herbs recommended in Guideline didn't have obvious effect and some had doubts about the manipulation of fumigation and washing in the part of other methods recommended in Guideline. Moreover, specification and procedure of manipulation of fumigation and washing using herbs and the acupuncture included in characteristic TCM therapy treating uncomplicated lower urinary tract infection remained to be developed.

Cloning and heterologous expression of sansanmycin biosynthetic gene cluster in Streptomyces coelicolor / 药学学报

Sansanmycins (SSs), produced by Streptomyces sp. SS, belong to uridyl peptide antibiotics which exhibit a good inhibitory effect on Mycobacterium tuberculosis and Pseudomonas aeruginosa. They share a unique chemical scaffold with a 4',5'-enamide-3'-deoxyuridine attached to DABA (N-methyl-2,3-diaminobutyryl) which was located in the peptide chain through peptide bond. In order to study the function of related genes and to employ synthetic biology to gain new SS derivatives, we obtained a complete SS biosynthetic gene cluster and heterologously expressed it in Streptomyces coelicolor M1146, M1152 and M1154. Fermentation broth of the recombinant strains were detected using HPLC and HPLC-MS/MS, and the result showed that SS-A was successfully produced in the three strains, and its production level in S. coelicolor M1154 was similar to the original wild type strain. In addition, a potential SS analogue named as SS-1154 was discovered from the fermentation broth of S. coelicolor M1154.

Establishment of a drug screening model for identifying up-regulator of human high density lipoprotein receptor / 中国医学科学院学报

<p><b>OBJECTIVE</b>To establish a new drug screening model based on transcriptional regulation of human high density lipoprotein (HDL) receptor gene CD36 and LIMPII analogous-1 (CLA-1) for discovering up-regulator of this receptor.</p><p><b>METHODS</b>The upstream regulatory sequence of CLA-1 was obtained by polymerase chain reaction. A recombinant reporter plasmid pGL3-CLAP was constructed by inserting the regulatory sequence upstream of luciferase gene of pGL3-Basic. Human hepatoma cell line BEL-7402 was transfected with pGL3-CLAP. Samples were detected by testing luciferase activity of transfected BEL-7402 cells in microtiter wells.</p><p><b>RESULTS</b>The drug screening model was established and optimized. Significant difference was present between pGL3-CLAP and pGL3-Basic transfected BEL-7402 cells (P< 0.001), and coefficient of variation was less than 10%. After primary and secondary screening, 1 compounds and 3 fermentation extracts had up-regulating activities.</p><p><b>CONCLUSION</b>This new drug screening model may be efficiently used to screen up-regulators of human HDL receptor expression, which might become lead compounds for new anti-atherosclerosis drugs.</p>