Objective Multimeric cyclic RGD (Arg-Gly-Asp) peptides are capable of improving the integrin αvβ3-binding affinity due to the polyvalence effect.In this study,the authors prepare 99Tcm-la-bearing cyclic RGD tetramer E{E[c(RGDfK)]2}2,and evaluate its biodistribution and imaging in nude mice beating U87 MG human glioma xenografts with integrinαvβ3-positive.Methods 99Tcm-hydrazino-nictinamide (HYNIC)-E{E[c(RGDfK)]2}2 was prepared by two-step method,while HYNIC wag chosen as bifunctional chelator,and tricine and trisodium triphenylphosphine-3,3,3-trisuifonate (TPPTS) as coligands.The af-finity of c (RGDyK) monomer,HYNIC-E[c(RGDfK)]2 dimer and HYNIC-E{E[c(RGDfK)]2}2 tetramer to integrin αvβ3 was compared by in vitro competitive assay against binding of 125I-c(RGDyK)to integrin αvβ3.positive U87 MG human glioma cells.The biodistribution [the percentage of injection dose per gram of tissue(%ID/g)] and imaging were performed in nude mice bearing UB7MG human glioma xenografts.Re-suits The labeling yield of 99Tcm-HYNIC-E{E[c(RGDfK)2}2 was over 95%,and the radiochemical purity was more than 99%after purification with Sop-Pak C18 cartridge.The 50%inhibiting concentration (IC30) val-ues of c(RGDyk),HYNIC-E[c(RGDfK)]2 and HYNIC-E{E[c(RGDfK)]2}2 were 85.9,9.5 and 4.5 nmol/L, respectively.The result indicated that RGD tetramer possessed a significantly higher affinity to in-tegrinαvβ3.The biodistribution data showed that 99Tcm-HYNIC-E{E[c(RGDfK)]2}2 was excreted mainly through kidneys.The tumor uptake of 99Tcm-HYNIC-E{E[c(RGDfK)]2}2 was two times higher than 99Tcm- HYNIC-E[c(RGDfK)]2,at 1h postinjection,with the uptake of(10.32±0.07)%ID/g and(5.15±0.52)%ID/g,respectively,which was consistent with the in vitro competitive binding data.The tumor up-tale of 99Tcm-HYNIC.E{E[c(RGDfK)]2}2 was still as higher as(9.35±1.35)%ID/g at 4 h postinjec-tion, which demonstrated that the retention time of radiotracer in tumor was long enough.The imaging showed that tumor was clearly visualized at 1h postinjection,and the image at 4 h postinjection Was better.Conclusion The higher tumor uptake and longer retention time in tumor make 99Tem-HYNIC-E{E[c(RG-DfK)J 2}2 a promising radiotracer for integrinαvβ3-positive tumors imaging,furthermore,suggest that radi-onuelides(such as 90Y).1abeled RGD tetramer is more suitable for the therapy of integrin αvβ3-positive tumors.

In recent years, artificial intelligence (AI) technology has advanced rapidly and has been widely applied in various fields such as medicine and pharmacy, accelerating the drug development process. Focusing on the application of AI in the discovery and optimization of lead compounds, this review provides a detailed introduction to AI-assisted virtual screening and molecular generation methods for discovering lead compounds, while particularly highlighting the cases of AI-drived drugs into clinical trials. Additionally, we briefly outline the application of AI basic algorithm models in quantitative structure-activity relationship (QSAR) and drug repurposing, offering insights for AI-based drug discovery.

In the present study, the genome shuffling was used to improve lipase production of Penicillium expansum. A lipase producing mutant strain-Penicillium expansum FS8486 and a wild type of Aspergillus Tamarii FS-132 isolated from soil of a volcano in Xinjiang were used as the parental strains. After two rounds of genome shuffling, several elite daughter strains were screened. The lipase activity in one of the daughter strains was increased 317% over the starting strain FS8486. Comparisons of the morphology, RAPD (Random Amplification of Polymorphic DNA) polymorphism and the fatty acid compositions between the daughter and the parental strains suggested that the filial generation were generated by genome shuffling. In this study, the genome shuffling used successfully first time in eukaryotic microorganism and increases the production of the desired metabolite in short time, the study will be useful to spread the genome shuffling in eukaryotic microbial breeding.
Aspergillus ; genetics ; DNA Shuffling ; methods ; Genetic Enhancement ; methods ; Genome, Fungal ; genetics ; Lipase ; biosynthesis ; genetics ; Penicillium ; enzymology ; genetics ; Random Amplified Polymorphic DNA Technique

OBJECTIVETo study the mechanism and significance of peripheral blood mononuclear cell (PBMC) of neonates infected with hepatitis B virus (HBV).

METHODSEighty-four HBsAg-positive and HBeAg-negative mothers and their newborns were recruited in this study. Sixteen hepatitis B virus markers (HBVM)-negative mothers and their neonates were served as control. All these cases had no symptoms of hepatitis, serious pregnancy complications and preexisting disease. Age, gestational age and the method of delivery were matched in two groups (P > 0.05). Five ml blood samples were taken from the peripheral vein of the pregnant women before delivery and from neonates within 24 hours after birth, before inoculation of HBV vaccine (HBVac). Serum and PBMC were isolated from 2 ml and 3 ml samples respectively. The sera, PBMC and the last supernatant of PBMC washing were stored at -80 degrees C. HBVM of neonates were detected by using enzyme linked immunosorbent assay (ELISA). HBV DNA in serum, PBMC and the last supernatant of PBMC washing of mothers and neonates were detected by using a nested-polymerase chain reaction (n-PCR). Two pairs of oligonucleotide primers, the outer primer pair for first PCR and inner primer pair for second PCR, designed according to region S of HBV genome were synthesized at Shanghai Cell Biology Institute of Chinese Academy of Sciences. The neonates who were HBV DNA positive in PBMC but HBsAg and HBV DNA negative in serum were followed up for one year, HBsAb in serum and HBV DNA in PBMC were observed in the neonates.

RESULTS(1) The positive rate of HBV DNA in 84 serum and PBMC of mothers were 53.57% and 40.48%, respectively (chi(2) = 2.891, P > 0.05). All the results were weakly positive. (2) Twenty-four (28.57%) newborns in the study group were infected, including 7 who were only HBV DNA positive in serum, 11 only HBV DNA positive in PBMC and 6 in both, all the results were weakly positive. HBsAg was negative in all the newborns. None of the neonates in control group was infected with HBV. There was significant difference between the two groups (chi(2) = 4.55, P < 0.05). (3) Of all the study cases, 11 (13.10%) neonates were HBV DNA weakly positive in PBMC but HBsAg and HBV DNA negative in serum. Of their mothers, 5 were only HBV DNA positive in serum, 2 only positive in PBMC and 4 positive in both serum and PBMC. Seven of the 11 neonates were followed up for one year and at the end of follow-up, 4 were HBsAb positive and HBV DNA negative in PBMC; 3 were HBsAb negative, and among the 3 cases HBV DNA in 2 was still positive in PBMC, HBsAg and HBV DNA in serum were negative in all the 7 neonates.

CONCLUSION(1) HBV DNA positivity either in serum or in PBMC in mothers can result in infection of PBMC with HBV in their neonates. (2) PBMC infection with HBV can exist for a long time in neonates while HBsAg and HBV DNA are negative in serum, and may result in vaccination failure in neonates.

Case-Control Studies ; DNA, Viral ; blood ; Female ; Hepatitis B ; diagnosis ; immunology ; Hepatitis B Vaccines ; administration & dosage ; Hepatitis B virus ; Humans ; Infant, Newborn ; Infectious Disease Transmission, Vertical ; Leukocytes, Mononuclear ; virology ; Pregnancy

OBJECTIVETo construct a eukaryotic expression vector encoding the gene of extracellular region of type II transforming growth factor beta receptor (sTGFbetaR II), to express the protein in CHO cell line and to determine its biological activity.

METHODSThe extracellular region (amino acids 1-159) of the human TGFbetaR II cDNA was amplified by PCR from a TGFbetaR II chimeric plasmid,and the eukaryotic expression plasmid pCDNA3.1/myc-his(-)B-sTGFbetaR II(pCDNA-sTGFbetaR II) was constructed by inserting the sTGFbetaR II cDNA into the EcoR I/Hind III-digested pCDNA. The DNA sequence was confirmed by double digestion and the pCDNA-sTGFbetaR II plasmid was transfected into the CHO cell line. The sTGFbetaR II protein was confirmed by Western blotting analysis and its biological function was determined.

RESULTSThe specific protein was observed in western blotting, and the protein abrogated the growth-inhibitory effects of TGF-beta1 on mink lung epithelial cells (Mv1Lu).

CONCLUSIONThe eukaryotic expression plasmid pCDNA-sTGFbetaR II has been successfully constructed and the sTGFsTGFbetaR II protein with biological activity obtained.

Amino Acid Sequence ; Animals ; Base Sequence ; CHO Cells ; Cloning, Molecular ; Cricetinae ; DNA, Complementary ; Eukaryotic Cells ; metabolism ; Genetic Vectors ; Humans ; Molecular Sequence Data ; Plasmids ; genetics ; Protein-Serine-Threonine Kinases ; Receptors, Transforming Growth Factor beta ; biosynthesis ; genetics ; Recombination, Genetic ; genetics ; Transfection

OBJECTIVETo understand the HBV infection rate of peripheral blood mononuclear cells (PBMCs) from fetuses of HBsAg positive mothers, associated risk factors and to explore the clinical significance of detecting HBV infected PBMCs.

METHODSSixty eight pregnant women who were delivered at the First Hospital of Xi'an Jiaotong University, China from August 1995 to February 1997, and their newborns were studied. They were divided into two groups according to their status of HBV serological markers. The study group included 50 cases who were serum HBsAg positive and 18 cases without any HBV serum markers served as control group. All these cases had no symptoms of hepatitis, high risk premature labor, premature delivery and hypertensive disorder complicating pregnancy. Age and gestational age were matched in two groups. Blood samples (5 mL) were taken from the peripheral vein of pregnant women before delivery and from newborns within 24 h after birth, before inoculation of HBV vaccine (HBVac) and injection of hepatitis B immunoglobulin (HBIG). PBMCs were isolated. The sera and PBMCs were stored at -80 degrees C. HBV-DNA in serum and PBMCs were detected with nested polymerase chain reaction (n-PCR). Two pairs of oligonucleotide primers, the outer primer pair for first PCR and inner primer pair for second PCR, designed according to region S of HBV genome were synthesized by Shanghai Cell Biology Institute of Chinese Academy of Science.

RESULTSThe detection rate of HBV-DNA in serum and PBMCs from HBsAg positive pregnant women was 60.0% (30/50) and 40.0% (20/50), respectively. The detection rate of HBV-DNA in serum and PBMCs from newborns of HBsAg positive pregnant women was 46.0% (23/50) and 30.0% (15/50), respectively. Ten newborns were HBV-DNA positive in serum only, 2 were positive in PBMCs only and 13 were positive in both serum and PBMCs. In the control group, HBV-DNA was not detected in PBMC nor in serum. The positive rate of HBV-DNA in PBMCs of newborns was significantly higher in the group of mothers who were HBV-DNA or HBeAg positive in serum (P < 0.05, P < 0.01); the positive rate was significantly higher in the group of mothers who were HBV-DNA positive in both serum and PBMC than that in the group of mothers who were serum HBV-DNA positive only (P < 0.01); and it was markedly higher in the group of mothers who were PBMC HBV-DNA positive than that in group of mothers who were HBV-DNA negative in PBMCs (P < 0.01). The positive rate of HBV-DNA in PBMCs of newborns was significantly higher in the group of newborns who were HBV-DNA positive in serum than that in the group of newborns who were HBV-DNA negative in serum (P < 0.05).

CONCLUSIONSThe positive rate of HBV-DNA in PBMCs from newborns of HBsAg positive pregnant women was 30.0% (15/30). It was related to HBV viremia level and HBV-DNA status in PBMCs of mothers and newborns. Detection of HBV-DNA in PBMCs may be an important supplementary method to determine intrauterine HBV infection, and can predict the response to HBV vaccine.

Adult ; Case-Control Studies ; DNA, Viral ; blood ; Female ; Hepatitis B Vaccines ; administration & dosage ; Hepatitis B virus ; immunology ; isolation & purification ; Humans ; Immunoglobulins ; administration & dosage ; Infant, Newborn ; blood ; Infectious Disease Transmission, Vertical ; prevention & control ; Injections, Intramuscular ; Leukocytes, Mononuclear ; virology ; Male ; Mothers ; Polymerase Chain Reaction ; Pregnancy ; blood ; Risk Factors ; Time Factors ; Treatment Outcome

OBJECTIVETo study the role of the HBV-infected mothers' PBMC in intrauterine transmission of HBV to their fetuses.

METHODSThirty pregnant women with serum HBV DNA negative and PBMC HBV DNA positive and their newborns were used as the study group. Ten pregnant women with serum HBV negative and their infants served as the control group. HBV DNA in serum and in PBMC was detected using nested polymerase chain reaction (n-PCR). The mothers' PBMC in newborns' peripheral blood was examined using heminested-PCR.

RESULTSFour newborns were serum HBV DNA positive and 8 newborns were HBV DNA positive in PBMC in the study group. Among them, 2 newborns were HBV DNA positive in both serum and PBMC, 6 cases were positive in PBMC only, and 2 cases were positive in serum only. Five mothers had the GSTM1 gene; and it was not detected in 3 newborns. Among the 8 newborns with HBV DNA positive in PBMC, 3 did not have the GSTM1 gene, at the same time their mothers possessed the GSTM1 gene. Mothers' PBMC were detected in all of these three newborns' peripheral blood. HBV DNA in serum and in PBMC of the control group infants were all negative.

CONCLUSIONHBV-infected PBMC of the mother may serve as a vector in HBV intrauterine infection.

Adult ; DNA, Viral ; analysis ; Female ; Hepatitis B virus ; isolation & purification ; Hepatitis B, Chronic ; blood ; transmission ; Humans ; Infant, Newborn ; Infectious Disease Transmission, Vertical ; Leukocytes, Mononuclear ; virology ; Pregnancy ; Pregnancy Complications, Infectious ; virology

The biological characters of Sindbis virus strain of Yunnan(YN87448 strain) were studied by the test of the filtration, acid-resistant, ether-resistant, CPE, susceptibility of animal, HA, plague, determination of virus titres, and the cross-HI, cross-IFAT and PRNT as well.The results indicated that YN87448 strain belongs to Sindbis virus, Alphavirus, Togaviridae. YN87448 strain virus was plaque purified(PYN87448). The biological character of PYN87448 strain virus was studied too. PYN87448 strain virus will be used in the molecule biological test.

Toxoplasma gondii is a worldwide distribution of Apicom-plexans,which are widely parasitic in human and warm-blooded animals.Due to the factors such as host and geographical distribution,the population structure has rich genetic diversity.At present,the study of the genotype of Toxoplasma gondii and summary papers are relatively few.This paper reviews the biological information that has been reported in the world regarding the toxoplasmosis of birds such as domesticated chickens,ornamental birds,pet birds and wild rare birds,and to provide basis for further research on biological information such as epidemiology of bird toxoplasmosis and population structure of insects.

Objective To develop an analytical method for analyzing the unbound concentration of antofloxacin in human plasma .Methods A HPLC method was developed to determine the unbound concentration of antofloxacin in human plasma using ultra -centrifugation.The column was Alltima C18 (150 mm ×4.6 mm,5μm) with room temperature as the column temperature .The mobile phase was composed of 13:87 acetoni-trile-0.05 mol · L-1 phosphate buffer ( pH 3.0 ) with detection wave-length set at 293 nm, and the flow rate was 1.0 mL · min-1 .The method was validated for specificity , precision and accuracy , recovery as well as stability.Results The calibration curves were linear over the range of 0.08-5.49 μg· mL-1 .The intra-day and inter-day preci-sion evaluated at lower limit of quantification and quality control levels were within 2.78%-10.03%.The recoveries calculated for the anto-floxacin were within 92.09%-108.96%from spiked plasma ultrafiltrate samples.Conclusion The analytical method is quick , precise and accuracy and could be used in the analysis of unbound concentration of antofloxacin in plasma.