To improve bond selectivity of recombinant β-glucuronidase in Escherichia coli (PGUS-E), based on the PGUS-E structure guidance, three key points R329, T369 and N467 were identified to be responsible for the bond selectivity of PGUS-E, and further saturation mutagenesis was conducted. Two positive mutants R329K and T369V were obtained by a combined selection technique of thin-layer chromatography and high performance liquid chromatography. Compared to PGUS-E, the bond selectivity of mutants R329K and T369V increased by 26.9% and 34.3%, respectively; whereas the biochemical properties such as pH and temperature profile were unchanged. Nevertheless, the activity was decreased compared to PGUS-E. These results further confirmed that sites R329 and T369 played important roles for the bond selectivity and activity. In summary, this study significantly increased the bond selectivity of PGUS-E by structure guided saturation mutagenesis, providing experimental support for elucidating the relationship between the structure and function of PGUS-E.
Chromatography, High Pressure Liquid ; Chromatography, Thin Layer ; Escherichia coli ; metabolism ; Glucuronidase ; chemistry ; Industrial Microbiology ; Mutagenesis ; Recombinant Proteins ; chemistry ; Temperature

Objective To investigate the developmental characters of neural stem cells(NSCs) in occipital of cortex from human fetal brain at different age.Methods Ninety cases of embryoes at gestational age 16-32 weeks and by induction of labor with water bag were collected for determining distribution,shapes,growth modes and the number of NSCs in the occipital of cortex with immunohisto- chemical method under light microscope.Results It was noted that NSCs existed in the occipital of cortex from human fetal brain at different ages.NSCs mainly distributed in layers of cone cells and inner granule cells.NSCs existed in the occipital of cortex of different fetal age included middling round cells,NSCs had enations from 0 to 1.Nucli were larger than plasm.Each NSC had nucleoli from 2-4 and rarefaction chromatin.Most of NSCs distributed in three growth modes including crowd,cluster and clone,occasionally with a single growth mode among other nerve cells.There were no differences including distribution,shapes,growth modes and the number of NSCs in the occipital of cortex between groups,but,NSCs gradually decreased with increasing of age.Conclusion NSCs exists in the occipital of cortex from different gestational age,and the number of NSCs decreases with increasing of age.

Age Distribution ; Aged ; China ; epidemiology ; Female ; Humans ; Male ; Middle Aged ; Sex Distribution ; Surveys and Questionnaires ; Tobacco Smoke Pollution ; statistics & numerical data

Vaccination has been proved to be the most effective strategy to prevent the Corona Virus Disease 2019 (COVID-19). The mRNA vaccine based on nano drug delivery system (NDDS) - lipid nanoparticles (LNP) has been widely used because of its high effectiveness and safety. Although there have been reports of severe allergic reactions caused by mRNA-LNP vaccines, the mechanism and components of anaphylaxis have not been completely clarified yet. This review focuses on two mRNA-LNP vaccines, BNT162b2 and mRNA-1273. After summarizing the structural characteristics, potential allergens, possible allergic reaction mechanism, and pharmacokinetics of mRNA and LNP in vivo, this article then reviews the evaluation methods for patients with allergic history, as well as the regulations of different countries and regions on people who should not be vaccinated, in order to promote more safe injection of vaccines. LNP has become a recognized highly customizable nucleic acid delivery vector, which not only shows its value in mRNA vaccines, but also has great potential in treating rare diseases, cancers and other broad fields in the future. At the moment when mRNA-LNP vaccines open a new era of nano medicine, it is expected to provide some inspiration for safety research in the process of research, development and evaluation of more nano delivery drugs, and promote more nano drugs successfully to market.

OBJECTIVETo retrospectivly compare the clinical efficacy of dynamic hip screw (DHS) with proximal femoral nail anti-rotation (PFNA) for the treatment of unstable intertrochanteric fractures in the elderly.

METHODSTotally 92 elderly patients with unstable intertrochanteric fractures were treated with DHS [including 27 males and 23 females with a mean age of (72.5 +/- 5.3) years old] and PFNA [including 22 males and 20 females with a mean age of (72.8 +/- 5.8) years old] from August 2008 to August 2012. The data of operation time,blood loss (obvious and hidden blood loss), bedridden time, down load time, postoperative complications and Harris hip function score were recorded and compared.

RESULTSBoth of two groups were followed-up for 10 to 18 months with an average of 13.5 months. PFNA was implanted with a significantly smaller incision and shorter clinical healing time, less blood loss,while hidden blood loss were more. Postoperative complications, therapeutic effects and Harris score in PFNA group were better than that of DHS group.

CONCLUSIONFor treatment of senile patients with unstable intertrochanteric fractures, PFNA was superior to DHS in reducing complication rates, recovering hip joint, while DHS could reduce perioperative blood loss in treating type II a, II b and III fracture.

Aged ; Aged, 80 and over ; Bone Nails ; Bone Screws ; Case-Control Studies ; Female ; Femur ; surgery ; Fracture Fixation, Internal ; instrumentation ; Hip Fractures ; surgery ; Humans ; Internal Fixators ; Male ; Middle Aged ; Retrospective Studies ; Treatment Outcome

Objective To study the effects of curcumin mediated photodynamic therapy (PDT)on the growth and proliferation in human cervical cancer cell line H8 in vitro and in vivo,and to investigate its antitumor mechanisms.Methods The effects of curcumin mediated PDT on proliferation of human cervical cancer H8 cell by MTT assay was used to screen the optimal parameter.Changes in cell morphology were observed by May-Gr ünwald-Farbstoff Giemsa staining.The apoptosis rate was estimated by flow cytometry.The effect of PDT by curcumin on the expressions of Bcl-2,P53 and survivin in H8 cells was detected by fluorescence real-time reverse transcription-polymerase chain reaction (RT-PCR).Forty BALB/C nude mice underwent subcutaneous injection of H8 cell line so as to establish animal models,and then were randomly divided into four equal groups:control group,irradiation alone group,curcumin alone group,curcumin PDT group.HE staining and pathological examination were performed.Immunohistochemical study was conducted to detect the protein expression of the apoptosis inhibiting genes of Bcl-2.Results The proliferation inhibition of H8 cells was obvious after PDT when curcumin 5μmol/L with irradiation 100 J/cm2,and with dose dependent manner.Typical morphologic features of apoptosis appeared characterizedly by marked chromatin condensation,nuclear pyknosis and fragmentation,and the appearance of apoptotic bodies.The total apoptosis rate was higher in PDT group [(47.21 ± 4.11)％]than in control group(1.71 ±0.16) ％ (P＜0.01).The mRNA expression of Bcl-2,P53 and survivin in H8 cells were suppressed significantly.HE staining showed remarkable subcutaneous necrosis in the PDT group.Immunohistochemistry showed remarkable down-regulation of protein expression of Bcl-2(P＜0.01).Conclusions Curcumin-mediated photodynamic therapy has a significant killing effect on H8 cells in vivo and in vitro.Its antitumor effect might be related to induction of Tumor cell apoptosis and suppression of Bcl-2 mRNA and protein expression.

Objective To explore the expressions of superoxide dismutase(SOD)and matrix metalloproteinase-3(MMP-3) in the brain tissues of newborn rat after hypoxic-ischemic(HI) and the effects of progesterone(PROG) on SOD and MMP-3 expression.Methods Seventy-two neonatal SD rats were randomly divided into 4 groups:normal control group(normal group),sham-operated group,HI group and PROG group.The model of neonatal rat with hypoxic-ischemic brain damage(HIBD) was made.The permeability of the blood-brain barrier was observed by using transmission electron microscopy,the level of SOD in the brain was assessed by hydroxylammoniumchloride autoxidation,MMP-3 protein expression in cerebral cortex part of the brain was detected by immunohistochemical.SPSS 12.0 software was used to analyze the data.Results In normal group and sham-operated group,capillary vessel′s morphology of blood brain barrier of neonatal rats were integrity and smooth,and structure were clarity.The permeability of blood-brain barrier in HI group was obviously enhanced and had slight changes in PROG group.Compared with the sham-operated group,the level of SOD in HI group significantly decreased(P

The study on the Rauvolfia verticillata (Lour.) Baill., which belongs to Apocynaceae, was carried out to look for its chemical constituents and pharmacological activity. The isolation and purification were performed by chromatography on silica gel, Sephadex LH-20 and ODS (octadecyl silane) open column. The structures of obtained compounds were elucidated on the basis of physicochemical properties and spectral analysis. Three indole alkaloids and one acridone alkaloid were isolated from chloroform layer extract and identified as ajmalicine B (1), sandwicine (2), raunescine (3) and 7-hydroxynoracronycine (4) separately. Ajmalicine B (1) is a new compound belonging to indole alkaloid. Compound 4 as an acridone alkaloid was a new type compound isolated from Rauvolfia genus for the first time. We also did some biological activity research on the new type compound (4) to explore other pharmacological activities in addition to antihypertensive activity.
Animals ; Antineoplastic Agents, Phytogenic ; chemistry ; isolation & purification ; pharmacology ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; pharmacology ; HL-60 Cells ; Humans ; Indole Alkaloids ; chemistry ; isolation & purification ; pharmacology ; Inhibitory Concentration 50 ; Intestine, Small ; physiology ; MCF-7 Cells ; Molecular Structure ; Muscle Relaxation ; drug effects ; Muscle, Smooth ; physiology ; Plant Roots ; chemistry ; Plant Stems ; chemistry ; Plants, Medicinal ; chemistry ; Rabbits ; Rauwolfia ; chemistry

In order to clarify material basis of effective parts of liangxue tongyu prescription, blood-heat and blood-stasis rat model induced by dry yeast was established. The changes of rectal temperature, blood viscosity and plasma viscosity were used to evaluate the cooling-blood and activating-blood effects of liangxue tongyu prescription and its parts. Compared with the model group, the extract from liangxue tongyu prescription, its volatile oil and n-butanol part could significantly reduce rectal temperature (P<0.01), and also reduce blood viscosity and plasma viscosity to various degrees (P<0.01 or P<0.05). So volatile oil and n-butanol part were primarily identified as effective parts of liangxue tongyu prescription. By using GC-MS with normalization method of area to analyze volatile oil of liangxue tongyu prescription, 70 compounds were identified, accounting for about 92.54%, mainly as β-asarone, paeonol, α-asarone and shyobunone. 42 compounds such as peony glycosides, tannins, and iridoid glycosides were identified by HPLC-MS techniques and standard comparison. The study determined the effective parts of liangxue tongyu prescription and clarified the chemical composition providing the foundation for further studies on material basis of liangxue tongyu prescription.
Acetophenones ; chemistry ; Animals ; Anisoles ; chemistry ; Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; chemistry ; Gas Chromatography-Mass Spectrometry ; Oils, Volatile ; chemistry ; Rats ; Tannins ; chemistry

OBJECTIVETo find out the situation of the implementation on "rules on stop smoking in the public places in Beijing", a study was carried out to compare the results from 1997 and 2001.

METHODSThousands of residents aged above 15 in a family were sampled by stratified sampling, and 4 districts were selected as study locales.

RESULTS(1) About 40% of the department or school leaders considered much about the work on banning of smoking with 70 % of the departments or schools having posters of signs on 'ban on smoking' in the meeting rooms. (2) Some of the departments or schools had inspectors looking after the issue. (3) 60% of the people had never or 10% had seen that the inspectors ever criticizing or punishing the smokers who violating the rules. (4) People still often saw some one would smoke in public (the rates were 19.53% , 37.89% , 6.35% respectively in 1997,2001,2004 ). (5) People received the information of these rules through TV news or newspaper.

CONCLUSIONAlthough success had been achieved since the implementation of the Rules, it did not seem to have had substantial progress.

Adolescent ; Adult ; Aged ; China ; Data Collection ; Humans ; Middle Aged ; Public Policy ; Public Sector ; Smoking Prevention