Hydrogel is a creative polymeric biomaterial which can resemble extracellular matrix (ECM) in vitro. Hydrogel is also a material with intrinsic bioinert, but it can offer mechanical support and developmental guide for cell growth and new tissue organization by designing physicochemical and biological properties of hydrogels precisely. This review mainly introduces design of hydrogels, properties and applications in tissue engineering and regenerative medicine, drug delivery, stem cell culture and cell therapy.
Biocompatible Materials ; Cell Culture Techniques ; Extracellular Matrix ; Humans ; Hydrogels ; chemistry ; Regenerative Medicine ; Stem Cells ; Tissue Engineering

Objective To investigate the effects of penehyclidine hydrochloride (PHCD)on cerebral ischemia-reperfusion injury induced by intrauterine distress in fetal rats.Methods Eighty mature fetal rats weighing 4.52-4.81 g were randomly divided into four groups (n =20):sham opera-tion group(group S),PHCD control group (group S+ P),cerebral IR group (group IR),PHCD treatment group(group IR+P).Fetal rat intrauterine distress model was set up by clamping bilateral uterine horn vessels of pregnant rats.PHCD 2 mg/kg was injected in pregnant rat’s gluteus at 30 min before intrauterine distress model was set up in group IR+P,the same volume saline was injected in pregnant rat’s gluteus before shame operation in group S,the same volume PHCD was injected in pregnant rat’s gluteus before shame operation in group S+P.Fetal rats were decapitated at 12 h after the reperfusion,the peripheral blood of fetal rats was detected by blood gas analysis (including PH, PaO 2 ,PaCO 2 ,Lac);the infarct volume and the infarct volume fraction were detected by TTC stai-ning;pathological changes in lung tissue were observed by HE staining;the TNF-α,IL-6 content in the brain were detected by ELISA;the expression of NF-κB mRNA was detected by quantitative Real-time PCR,the expression of NF-κB p65 protein was detected by Western-blotting.Results The blood PH,PaO 2 in group IR and IR+P were lower than group S and S+P,the blood PH,PaO 2 in group IR+P was higher than group IR.Compared with group S and group S+P,the blood PaCO 2 , Lac,the infarct volume and the infarct volume fraction,the concentration of TNF-αand IL-6,the ex-pression of NF-κB mRNA and protein were significantly increased in group IR and IR+P (P <0.05), and those in group IR+P were lower than group IR (P <0.05 ).The pathological changes in brain tissue were significantly attenuated in group IR + P (P < 0.05 ).Conclusion Pretreatment with PHCDcouldattenuatecerebralischemia-reperfusioninjuryoffetalratsinducedbyintrauterinedistress. ThemechanismscouldrelatetotheinhibitionofNF-κBsignalingpathwayinbraintissues.

OBJECTIVE To investigate the produce of extended-spectrum ?-lactamases(ESBLs) and the presence of genotype of the ?-lactamases-encoding genes in Klebsiella pneumoniae isolated from the 98th Hospital of PLA,Huzhou,Zhejiang Province,China.METHODS Twenty-five strains of K.pneumoniae were isolated from the inpatients between Sep 2005 and Apr 2006.ESBLs were tested by phenotypic confirmatory tests recommended by CLSI.Twenty-one kinds of ?-lactamases genes of blaTEM,blaSHV,blaLEN,blaOKP,blaCTX-M-1 group,blaCTX-M-2 group,blaCTX-M-9 group,blaOXA-1 group,blaOXA-2 group,blaOXA-10 group,blCARB,blaPER,blaVEB,blaGES,blaLAP,blaDHA,blaACT/MIR,blaCMY/MOX,blaFOX,blaCMY/LAT,and blaACC were analyzed by PCR and verified by DNA sequencing.RESULTS In 25 strains of K.pneumoniae,the positive,negative,and "uncertainty" rates of ESBLs were 56.0%,20.0%,and 24.0%,respectively.The positive rate of genes of blaTEM,blaSHV,blaCTX-M-1 group,blaOXA-10 group,blaLAP,and blaDHA were 80.0%,4.0%,4.0%,80.0%,4.0% and 32.0%,respectively.The 15 kinds of rest genes were all tested negative.The total positive rate of 21 kinds of ?-lactamases gene was 92.0%.Among them,the blaLAP-2 gene sequence of the HZ12593 strain has been registered in GenBank(GenBank Accession Number: EU529981).CONCLUSIONS There are higher rate of ESBLs-producing strains in K.pneumoniae isolated from the inpatients,and at least 6 kinds of ?-lactamases gene existed.Both genes of blaTEM and blaOXA-10 group are the most common genotypes.Carring blaDHA Gene may influence the result of phenotypic confirmatory test for ESBLs in K.pneumoniae.

Objective To investigate the feasibility of hydrogen proton magnetic resonance spectroscopy (1 H-MRS)for detection of Wallerian degeneration of the pyramidal tract after cerebral infarction.Methods Multiple metabolic indices including NAA,Cho, Cr of the bilateral cerebral peduncle were detected by using 1 H-MRS in 1 5 patients with unilateral middle cerebral artery infarction and 1 5 age-matched healthy volunteers,NAA/Cr,Cho/Cr were also calculated.Comparing the difference between cerebral infarction group and the control group ,the ROC curve was analyzed.Results The values of NAA/Cr in the ipsilateral cerebral peduncle of cerebral infarction patients were significantly lower than that of the contralateral,and there were significant differences between the two groups(P <0.05).The values of NAA/Cr in the ipsilateral cerebral peduncle of cerebral infarction patients decreased (P <0.05),as compared with that of the control group.The area under the ROC curve was 0.947,the truncation point was 1.63.The NAA/Cr val-ues of the contralateral cerebral peduncle of cerebral infarction patients had no significant differences compared with the control group (P >0.05),the Cho/Cr values of the ipsilateral and the contralateral cerebral peduncle had no significant difference compared with the control group (P >0.05).Conclusion 1 H-MRS can detect Wallerian degeneration of the pyramidal tract after cerebral infarction.

C-arm based surgical navigation system is a kind of computer assisted surgery (CAS) system. In this paper, key techniques concerning this kind of system are presented. The key techniques mainly include XRII image distortion correction and C-arm imaging system calibration. On this basis, we designed relevant tools and made them fabricated, and developed a software system. Experimental results of human fresh spine sample showed that with the surgical navigation system, screw insertion accuracy was much higher than that without the surgical navigation system.
Algorithms ; Calibration ; Humans ; Radiographic Image Enhancement ; methods ; Radiographic Image Interpretation, Computer-Assisted ; methods ; Spine ; surgery ; Surgery, Computer-Assisted ; methods

In traditional Chinese medicine herbs (TCM), including Radix Salviae Miltiorrhizae (Danshen), Radix Puerariae Lobatae (Gegen), Radix Angelicae Sinensis (Danggui), and Rhizoma Chuanxiong (Chuanxiong) are widely used for the prevention and treatment of cardiovascular diseases and also often co-administered with Western drugs as a part of integrative medicine practice. Carboxylesterase 1 (CES1) plays a pivotal role in the metabolisms of pro-drugs. Since (S)-2-(2-(6-dimethylamino)-benzothiazole)-4,5-dihydro-thiazole-4-carboxylate (NLMe) has recently been identified by us as a selective CES1 bioluminescent sensor, we developed a rapid method using this substrate for the direct measurement of CES1 activity in rats. This bioluminescence assay was applied to determine CES1 activity in rat tissues after a two-week oral administration of each of the four herbs noted above. The results demonstrated the presence of CES1 enzyme in rat blood and all tested tissues with much higher enzyme activity in the blood, liver, kidney and heart than that in the small intestine, spleen, lung, pancreas, brain and stomach. In addition, the four herbs showed tissue-specific effects on rat CES1 expression. Based on the CES1 biodistribution and its changes after treatment in rats, the possibility that Danshen, Gegen and Danggui might alter CES1 ac-tivities in human blood and kidney should be considered. In summary, a selective and sensitive biolu-minescence assay was developed to rapidly evaluate CES1 activity and the effects of orally administered TCMs in rats.

OBJECTIVETo study the chemical constituents from aerial parts of Fallopia dumetosum.

METHODThe 80% ethanol extract was separated by means of silica gel and Sephadex LH-20 column chromatography. The compounds isolated from the plant were identified by physicochemical properties and spectroscopic evidence.

RESULTTen compounds were obtained and identified as emodin (1), physcion (2), quercetin (3), luteolin (4), 5"- methoxy-hydnocarpin (5), ethylparaben (6), protocatechuic acid (7), (2S,3S, 4R) -sphinganine-(2'R) -delta5'6' (E) -2'-hydroxyl tetracosanoylamino (8), beta-sitosterol (9), and daucosterol (10).

CONCLUSIONAnthraquinones and flavones were the major constituents of this plant. All compounds were isolated firstly from this plant, and compounds 5, 7, and 8 were isolated from the genus Fallopia for the first time.

Anthraquinones ; chemistry ; isolation & purification ; Flavones ; chemistry ; isolation & purification ; Plant Components, Aerial ; chemistry ; Plant Extracts ; chemistry ; Plants, Medicinal ; chemistry ; Polygonaceae ; chemistry

Palliative care,as the most special way to treat malignant tumors,is not only conducive to improving the quality of life and life value of patients,as well as alleviating the physical and mental pain of patients and their families,but also can help to relieve their financial burden and effectively avoid the waste of limited public resources.However,in the actual promotion of palliative care services,various ethical issues are encountered,such as the dignity of death,the need for psychological care,and the patient's right to independent decision-making.From the perspective of bioethics,by analyzing different types of practical disputes,this paper revealed their inherent ethical problems,and proposed specific countermeasures from the aspects of defending patient dignity,breaking the limitations of traditional cognition,and establishing a field model for joint decision-making between doctors and patients,so as to build a palliative care service model that suits China's national conditions and safeguard the patients'life rights and interests with malignant tumors.

[Objective]To investigate the effects of traditional Chinese medicine acupuncture combined with 0.01%atropine eye drops on macular vascular density and retinal thickness in children with low myopia.[Methods]A total of 84 children(156 eyes)newly diagnosed as low myopia were randomly divided into an experimental group and a control group.The experimental group received traditional Chinese medicine acupuncture combined with 0.01%atropine eye drops,while the control group was treated with 0.01%atropine eye drops alone.Ophthalmic examinations were performed before and after six months of treatment,including uncorrected distance visual acuity(UCVA),axial length(AL),spherical equivalent(SE),and slit-lamp examination.Optical coherence tomography(OCT)was used in routine mode to measure macular ganglion cell-inner plexiform layer(mGCIPL)thickness,and optical coherence tomography angiography(OCTA)was employed to measure macular vascular density and the area of the foveal avascular zone(FAZ).Changes in various indicators before and after treatment were compared between the two groups.[Results]After six months of treatment,both groups showed significant increases in AL and SE compared with that before treatment(P<0.01).The differences in AL and SE were significantly smaller in the experimental group than in the control group(P<0.05).No significant changes in intraocular pressure(IOP)were observed in either group before and after treatment(P>0.05).Compared to before treatment,both groups exhibited significant increases in mGCIPL thickness(P<0.01,P<0.05).Central circle macular vessel density(cCVD)increased in the experimental group(P<0.01),while there was no significant changes in outer circle macular vessel density(oCVD),inner circle macular vessel density(iCVD),whole circle macular vessel density(wCVD)or FAZ(P>0.05).After six months of treatment,no correlation was found between cCVD and AL or SE in the experimental group(P>0.05),but cCVD was positively correlated with mGCIPL thickness(r=0.448,P<0.05).[Conclusion]Traditional Chinese medicine acupuncture combined with 0.01%atropine eye drops can further reduce the growth rate of AL and diopter in children with low myopia.Additionally,this combined treatment increases cCVD and mGCIPL thickness in these children.

Objective: To analyze clonal evolution and clinical significance of trisomy 8 in patients with acquired bone marrow failure. Methods: The clinical data of 63 patients with acquired bone marrow failure accompanied with isolated trisomy 8 (+8) from June 2011 to September 2018 were analyzed retrospectively, the clonal evolution patterns and relationship with immmunosuppressive therapy were summarized. Results: Totally 24 male and 39 female patients were enrolled, including 39 patients with aplastic anemia (AA) and 24 patients with relatively low-risk myelodysplastic syndrome (MDS) . Mean size of+8 clone in MDS patients[65% (15%-100%) ]was higher than that of AA patients[25% (4.8%-100%) , z=3.48, P=0.001]. The patients were was divided into three groups (<30%, 30%-<50%,and ≥50%) according to the proportion of+8 clone. There was significant difference among the three groups between AA[<30%:55.6% (20/36) ; 30-50%: 22.2% (8/36) ; ≥50%22.2% (8/36) ]and MDS patients[<30%:19.0% (4/21) ; 30%-<50%:19.0% (4/21) ; ≥50%61.9% (13/21) ] (P=0.007) . The proportion of AA patients with+8 clone <30% was significantly higher than that of MDS patients (P=0.002) ; and the proportion of AA patients with+8 clone ≥50%was significantly lower than that of MDS patients (P=0.002) . The median age of AA and MDS patients was respectively 28 (7-61) years old and 48.5 (16-72) years old. Moreover, there was no correlation between age and+8 clone size in AA or MDS (r_s=0.109, P=0.125; r_s=-0.022, P=0.924, respectively) . There was statistical difference in total iron binding capacity, transferrin and erythropoietin between high and low clone group of AA patients (P=0.016, P=0.046, P=0.012, respectively) , but no significant difference in MDS patients. The immunosuppressive therapy (IST) efficacy of AA and MDS patients was respectively 66.7% and 43.8% (P=0.125) . Comparing with initial clone size (27.3%) , the +8 clone size (45%) of AA patients was increased 1-2 year after IST, but no statistical difference (z=0.83, P=0.272) . Consistently, there was no significant change between initial clone size (72.5%) and 1-2 year clone size (70.5%) after IST in MDS patients. There was no significant difference in IST efficient rate between +8 clone size expansion and decline group of in AA patients at 0.5-<1, 1-2 and>2 years after IST. We found four dynamic evolution patterns of +8 clone, which were clone persistence (45%) , clone disappearance (30%) , clone emergence (10%) and clone recurrence (15%) . Conclusions AA patients had a low clone burden, while MDS patients had a high burden of +8 clone. The +8 clone of AA patients didn’t significantly expanded after IST, and the changes of +8 clone also had no effect on IST response.