At the beginning of the 1980s, a concept of viable but non-culturable(VBNC) was suggested. VBNC is a survival strategy adopted by microorganisms when they are exposed to environmental stress. This article try to make a summary of research of the conditions of VBNC formation, recovery of culturability and methods of VBNC cells detection. In addition, introduces the first growth factor of microorganisms-Rpf.

This project is targeted on exploring some improving approaches to isolate and culture the microorganisms which are difficult to be isolated and cultured through the conventional ways. The results showed that betaine, sodium pyruvate, SOD and catalase are helpful for increasing the total number and variety of isolated strains. A kind of combined method was also used to isolate the micro-colony which can not be seen by naked eyes on the plates. Totally 52 Actinomycetes and 103 bacteria and 17 fungi were obtained from 4 soil samples using the above methods. 4. 325% microorganisms were obtained as positive strains to inhibit the growth of some kinds of test bacteria, which is higher than the percent using generally isolated ones. These microbial natural products may remain an important resource for the drug discovery.

In this study, the buffering capacity of amphiphilic pH-sensitivity copolymer poly(2-ethyl-2-oxazoline)-cholesteryl methyl carbonate (PEOZ-CHMC) was evaluated. The ammonium sulfate gradient method was used to prepare doxorubicin hydrochloride (DOX x HCl)-loaded liposomes (DOX-L), and then the post-insertion method was used to prepare PEOZ-CHMC and polyethylene glycol-distearoyl phosphatidyl ethanolamine (PEG-DSPE) modified DOX x HCl-loaded liposomes (PEOZ-DOX-L and PEG-DOX-L). The physico-chemical properties, in vitro drugs release behavior, cellular toxicity and intracellular delivery of liposomes were evaluated, separately. The results showed that PEOZ-CHMC has a satisfactory buffering capacity. The sephadex G-50 column centrifugation method and dynamic light scattering were used to determine the encapsulation efficiency (EE) and particle size of liposomes. The EE and particle size of DOX-L were (97.3 ± 1.4) % and 120 nm, respectively, and the addition of PEOZ-CHMC or PEG-DSPE had no influence on EE and particle size. The zeta potentials of three kinds of liposomes were negative. The release behavior of various DOX liposomes in vitro was investigated by dialysis method. In phosphate buffer solution (PBS) at pH 7.4, DOX x HCl was released from PEOZ-DOX-L in a sustained manner. While in PBS at pH 5.0, the release rate of DOX x HCl from PEOZ-DOX-L increased significantly, which suggested DOX x HCl was released from PEOZ-DOX-L in a pH-dependent manner. The intracellular delivery of liposomes was investigated by confocal laser scanning microscopy (CLSM). The CLSM images indicated that PEOZ-DOX-L showed efficient intracellular trafficking including endosomal escape and release DOX x HCl into nucleus, as well as the DOX-L and PEG-DOX-L had no this effect. The cytotoxicity of liposomes against MCF-7 cells was detected by using MTT assay. The results showed that antiproliferative effects of PEOZ-DOX-L enhanced with pH value decreased, whereas DOX-L and PEG-DOX-L did not have any significant difference in inhibitions at different pH conditions. Therefore, the problems of the inhibition of cellular uptake of liposomes and the failed endosomal escape of pH-sensitive liposomes by PEG chain can be overcome by the pH-sensitive liposomes constructed by PEOZ-CHMC.

To evaluate the value of silicone intubation and ring-fixed method in canalicular laceration.
●METHODS: A retrospective study of 36 cases with laceration of lacrimal canaliculus. For all the patients, microscope was used to find the broken ends of the lacrimal canaliculus, and then straight insertion was performed to the distant and near broken ends through the upper and lower lacrimal points, then passed the dacryocyst to insert nasolacrimal canal and ended up in inferior nasal meatus. Thus, clinical data about forming annular support to treat laceration of lacrimal canaliculus was presented here.
● RESULTS: All 36 patients with traumatic canalicular laceration were anastomosed successfully and all patients healed without infection. The surgery went well, intubation was smoothly, all patients were followed - up for another 6mo after the stent was removed. The accidental fall off of the stent was not observed during the follow - up. During the follow - up 10 - 18mo after extubation, when the stent was removed, 32 cases (88. 9%) recovered to normal lacrimal drainage function;4 cases ( 11. 1%) remained epiphora with obstructed lacrimal passage. All cases were no lower eyelid ectropion.
●CONCLUSlON: For the patients with inferior canalicular laceration, the silicone intubation and ring-fixed method is effective, low irritation and less complication.

Objective To analyze the karyotypes of 11 cases of Turner syndrome with marker chromosome,and study the phenotypic effects resulting from the abnormal karyotype.Methods Eleven Turner syndrome patients had a mosaic karyotype and carried a marker chromosome,and 6 marker chromosomes were ring chromosomes.Their karyotypes were showed as mos.45,X/46,X,+mar or mos. 45,X/46,X,+r.Fluorescence in situ hybridization(FISH)technique with X/Y centromere probes was performed to determine the origin of the marker chromosome.Reverse chromosome painting technique was used to identify the breakpoints of two largest markers.Phenotype effects with different chromosome breakpoints were compared.Results All the 11 marker chromosomes were ring X chromosomes.The breakpoints of the r(X)were involved in Xp22,Xq22,Xq24 and Xq26,etc.Conclusions The marker chromosomes in Turner syndrome mainly originate from X chromosome and form ring chromosome X.Each r (X)in our patients was mosaic,indicating it was originated from mitosis error during early embryo development.To analyze the origin of the marker chromosome and the breakpoint of r(X)will provide guidance for the therapy and prognosis of the Turner syndrome patient.

In this study, the buffering capacity of amphiphilic pH-sensitivity copolymer poly(2-ethyl-2-oxazoline)-cholesteryl methyl carbonate (PEOZ-CHMC) was evaluated. The ammonium sulfate gradient method was used to prepare doxorubicin hydrochloride (DOX x HCl)-loaded liposomes (DOX-L), and then the post-insertion method was used to prepare PEOZ-CHMC and polyethylene glycol-distearoyl phosphatidyl ethanolamine (PEG-DSPE) modified DOX x HCl-loaded liposomes (PEOZ-DOX-L and PEG-DOX-L). The physico-chemical properties, in vitro drugs release behavior, cellular toxicity and intracellular delivery of liposomes were evaluated, separately. The results showed that PEOZ-CHMC has a satisfactory buffering capacity. The sephadex G-50 column centrifugation method and dynamic light scattering were used to determine the encapsulation efficiency (EE) and particle size of liposomes. The EE and particle size of DOX-L were (97.3 ± 1.4) % and 120 nm, respectively, and the addition of PEOZ-CHMC or PEG-DSPE had no influence on EE and particle size. The zeta potentials of three kinds of liposomes were negative. The release behavior of various DOX liposomes in vitro was investigated by dialysis method. In phosphate buffer solution (PBS) at pH 7.4, DOX x HCl was released from PEOZ-DOX-L in a sustained manner. While in PBS at pH 5.0, the release rate of DOX x HCl from PEOZ-DOX-L increased significantly, which suggested DOX x HCl was released from PEOZ-DOX-L in a pH-dependent manner. The intracellular delivery of liposomes was investigated by confocal laser scanning microscopy (CLSM). The CLSM images indicated that PEOZ-DOX-L showed efficient intracellular trafficking including endosomal escape and release DOX x HCl into nucleus, as well as the DOX-L and PEG-DOX-L had no this effect. The cytotoxicity of liposomes against MCF-7 cells was detected by using MTT assay. The results showed that antiproliferative effects of PEOZ-DOX-L enhanced with pH value decreased, whereas DOX-L and PEG-DOX-L did not have any significant difference in inhibitions at different pH conditions. Therefore, the problems of the inhibition of cellular uptake of liposomes and the failed endosomal escape of pH-sensitive liposomes by PEG chain can be overcome by the pH-sensitive liposomes constructed by PEOZ-CHMC.
Cell Nucleus ; Doxorubicin ; analogs & derivatives ; chemistry ; Endosomes ; Formates ; chemistry ; Humans ; Liposomes ; chemistry ; MCF-7 Cells ; Microscopy, Confocal ; Particle Size ; Phosphatidylethanolamines ; Polyamines ; chemistry ; Polyethylene Glycols ; chemistry

To study the relationship between hematopoiesis and primordial germ cells, chick embryos at different developing stages were flatbed and located. After fixed by glutaral, the embryos were PAS and HE stained respectively, dehydrated serially, transparent, mounted, and were observed in situ or in cut sheet condition. The results showed: (1) the cellule amorphous and the disposition in chick embryo of PGCs were coincident no matter stained by PAS or HE staining, and HE staining could disclose the morphologic characteristics more clearly, exactly and completely; (2) genesis of blood island could be observed at the boundary of light and dark region of the extraembryonic blastoderm at about 26 hours; (3) both the blood vessel endothelium cells and free cells of the blood island were differentiated from PGCs. The generating of genuine yolk sac was at about 44 - 48 hours. It is concluded that the initial anatomic site of blood island genesis may be is mesoblast of extraembryonic blastoderm rather than the yolk sac; the blood vessel endothelium cells and the blood cells are generated parallel; the PGCs are the common ancestry of angioblast and HSC.
Animals ; Cell Differentiation ; Cell Movement ; Cells, Cultured ; Chick Embryo ; cytology ; Hematopoietic System ; cytology

Objective To evaluate the quality of the portal images acquired by computed radiography(CR)system and conventional screen-film system,respectively.Methods imaging plates (IP)and X-ray films of a home-devised lead phantom with a leakage of 6.45% were acquired,and modulation transfer function(MTF)curves of the both images were measured using edge method.Portal images of 40 nasopharyngeal cancer patients were acquired by IP and screen-film system respectively.Two doctors with similar experience evaluated the damage degree of petrosa] bone,the receiver operating characteristic(ROC)curve of CR images and general images were drawn according to two doctors evaluation results.Results The identification frequency of CR system and screen-film system were 1.159 and 0.806 Lp/mm respectively.For doctor one,the area under ROC curve of CR images and general images were 0.802 and 0.742 respectively.For doctor two,the area under ROC curve of CR images and general images were 0.751 and 0.600 respectively.The MTF curve and ROC curve of CR are both better than those of screen-film system.Conclusion The image quality of CR portal imaging is much better than that of screen-film system.The utility of CR in linear accelerator for portal imaging is promising in clinic.

Objective To explore the diversity of resting-state network of brain between the patients with leukoaraiosis and the healthy people. Methods 31 patients with leukoaraiosis (patients) and 27 healthy persons (controls) were checked with resting-state functional magnetic resonance imaging (rs-fMRI), and analyzed with the independent component analysis (ICA) to explore the resting-state functional brain network. Results The resting-state brain network was found in both the patients and the controls, which was coincident with the previous studies. The active areas were the same in both groups, and the activation was weaken in the patients than in the controls, especially in quadrate gyri, posterior cingulate cortex, superior temporal gyrus, superior parietal gyrus, anterior central gyrus, post central gyrus, insula and prefrontal cortex. Conclusion There is a significant diversity of resting-state network of brain between the patients with leukoaraiosis and healthy people in the activation of active areas.

OBJECTIVETo establish a fast and sensitive method for the detection of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in precision-cut rat liver slices by HPLC-MS/MS and to investigate isoniazid (INH) -induced oxidative DNA damage.

METHODSPrecision-cut liver slices (300 microm) were prepared from male rats, and incubated with INH (0.018 mol/L) for 2 h after 1 h preincubation. DNA in the slices was extracted and digested into free nucleosides at 37 degrees C. The samples were injected into HPLC-MS/MS after the proteins were removed. The level of oxidative DNA damage was estimated using the ratio of 8-OHdG to deoxyguanosine (dG).

RESULTSThe limit of detection of 8-OHdG was 1 ng/mL (S/N=3) and the intra-assay relative standard variation was 3.38% when one transition 284.3/168.4 was used as a quantifier and another two transitions 284.3/140.2, 306.1/190.2 as qualifiers. 8-OHdG and dG were well separated, as indicated by elution at 10.02 and 7.37 min, respectively. INH significantly increased the ratio of 8-OHdG to dG in rat liver slices (P<0.05).

CONCLUSION8-OHdG in precision-cut liver slices could be sensitively determined by HPLC-MS/MS. HPLC-MS/MS coupled with precision-cut tissue slices is a fast and reliable analytical technique to evaluate oxidative DNA damage of target tissues caused by procarcinogens and cytotoxins.

Animals ; Chromatography, Liquid ; DNA Damage ; drug effects ; Deoxyguanosine ; analogs & derivatives ; analysis ; Humans ; Isoniazid ; pharmacology ; Liver ; drug effects ; metabolism ; Male ; Oxidative Stress ; drug effects ; Rats ; Rats, Wistar ; Sensitivity and Specificity ; Spectrometry, Mass, Electrospray Ionization ; Time Factors