Hyaluronic acid (HA) possesses excellent biocompatibility, biodegradability, and non-immunogenicity, and exhibits active targeting capability to receptors such as cluster of differentiation 44 (CD44). Therefore, HA has become an important material for the design and preparation of drug delivery carriers in recent years. HA is rich in functional groups that can be chemically modified, but different modification methods and sites can affect its biological properties. This paper summarizes and discusses the effects of chemical modification on the biological properties of HA based on the formation mechanisms of such properties, as well as the derivatization and characterization methods of HA, so as to provide some reference for rational research on chemical modification of HA.

Objective:To explore the optimal ratio of dihydrotestosterone and hydroxyflutamide (hereinafter referred to as DH), construct a dual release system of androgen and its antagonist, and analyze the application effect of this system in the repair of full-thickness burn wounds in mice.Methods:This study was an experimental study. The HaCaT cells were divided into blank group (without drug culture), low baseline group, medium baseline group, and high baseline group according to the random number table (the same grouping method below), and the last three groups of cells were cultured by adding three different ratios of DH. Under a medium ratio, the mass of dihydrotestosterone in the three baseline groups from low to high was 1.4, 2.8, and 4.0 μg, respectively, and the mass of hydroxyflutamide was 1.2, 1.6, and 2.0 μg, respectively. On this basis, under a small ratio, the mass of dihydrotestosterone was reduced by half and the mass of hydroxyflutamide was increased by half; under a large ratio, the mass of dihydrotestosterone was increased by half and the mass of hydroxyflutamide was reduced by half. After culture of 2 days, the cell proliferation level was detected by cell counting kit 8 ( n=4). Sixteen 6-8-week-old male BALB/c mice were used to establish a full-thickness burn wound on the back and divided into blank group, small ratio group, medium ratio group, and large ratio group, with 4 mice in each group. On post injury day (PID) 7, normal saline containing different ratios of DH was locally dropped to the wounds of mice in the last three groups of mice (the total mass of DH in the three ratio groups from small to large was 127.5, 165.0, and 202.5 μg, respectively, and the mass ratios of dihydrotestosterone to hydroxyflutamide (hereinafter referred to as drug mass ratio) were 8∶9, 8∶3, and 8∶1, respectively), afterwards, the administration was repeated every 48 hours until PID 27; normal saline was dropped to the wound of mice in blank group at the aforementioned time points. The wound healing status on PID 0 (immediately), 7, 14, 21, and 28 was observed, and the wound healing rates on PID 7, 14, 21, and 28 were calculated ( n=4). On PID 28, the wound tissue was taken, which was stained with hematoxylin and eosin for observing re-epithelialization and with Masson for observing collagen fibers, and the proportion of collagen fibers was analyzed ( n=3). Twenty 6-8-week-old male BALB/c mice were used to establish a full-thickness burn wound on the back and divided into ordinary scaffold group, small proportion scaffold group, medium proportion scaffold group, and large proportion scaffold group (with 5 mice in each group). On PID 7, the wound was continuously dressed with a polycaprolactone scaffold without drug and a polycaprolactone scaffold containing DH with a drug mass ratio of 1∶3, 1∶1, or 3∶1 (i.e. the dual release system of androgen and its antagonist, with total mass of DH being about 1.7 mg) prepared by using electrospinning technology until the end of the experiment. Histopathological analyses of tissue ( n=3) at the same time points as those in the previous animal experiment were performed. On PID 7 and 14, the wound exudates were collected and the relative abundance of bacterial communities was analyzed using 16S ribosomal RNA high-throughput sequencing ( n=3). Results:After culture of 2 days, under a small ratio, the proliferation levels of HaCaT cells in low baseline group and high baseline group were significantly higher than the level in blank group ( P<0.05). As the time after injury prolonged, the wounds of all four groups of mice continued to shrink. On PID 14, the wound healing rate of mice in large ratio group was 72.5% (61.7%, 75.1%), which was close to 53.3% (49.5%, 64.4%) in blank group ( P>0.05); the wound healing rates of mice in small and medium ratio groups were 74.2% (71.0%, 84.2%) and 70.4% (65.1%, 74.4%), respectively, which were significantly higher than the rate in blank group (with both Z values being -2.31, P<0.05). On PID 21, the wound healing rate of mice in small ratio group was significantly higher than that in blank group ( Z=-2.31, P<0.05). On PID 28, the wounds of mice in the three ratio groups were completely re-epithelialized and the epidermis was thicker than that in blank group; compared with that in blank group, the collagen fiber content in the wound tissue of mice in the three ratio groups was higher and arranged more orderly, and the proportions of collagen fibers in the wound tissue of mice in small and large ratio groups were significantly increased ( P<0.05). On PID 28, the wounds of mice in ordinary scaffold group were partially epithelialized, while the wounds of mice in the three proportion scaffold groups were almost completely epithelialized. Among them, the wounds of mice in small proportion scaffold group had the thickest epidermis. The proportion of collagen fibers in the wound tissue of mice in small proportion scaffold group was significantly increased compared with that in ordinary scaffold group ( P<0.05). On PID 7, the bacterial communities with high relative abundance in the wound exudation of mice in the four groups included bacteria of Corynebacterium, Staphylococcus, and Rhodococcus. On PID 14, the bacterial communities with high relative abundance in the wound exudation of mice in the four groups included bacteria of Stenotrophomonas, Rhodococcus, and Staphylococcus, and the number of bacterial species in the wound exudation of mice in the three proportion scaffold groups was more than that in ordinary scaffold group. Conclusions:When the drug mass ratio is relatively small, DH has the effect of promoting the proliferation of HaCaT cells. The ratio of 8∶9 is the optimal mass ratio of dihydrotestosterone to hydroxyflutamide, and DH with this mass ratio can promote re-epithelialization and collagen deposition of full-thickness burn wounds in mice, and promote wound healing. The constructed dual release system of androgen and its antagonist with DH in a 1∶3 drug mass ratio contributes to the re-epithelialization and collagen deposition of the full-thickness burn wounds in mice, and can improve the diversity of wound microbiota.

Objective: To explore the relationship between glycemic control and visceral adiposity index (VAI) among type 2 diabetes mellitus (T2DM) patients.Methods: A community-based epidemiological field study for patients with T2DM aged ≥ 40 years was conducted in China.Every participant underwent physical examinations, biochemical tests of fasting glucose, glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and so on, and a questionnaire, including anthropometric characteristics, lifestyle, disease history, family history, and medication use.Those participants with HbA1c ≥7.0% were classified as the poorly controlled in our analysis of relationship between glycemic control and VAI.Anthropometric characteristics, lifestyle, and biochemical indexes of the participants were compared among the groups of different VAI levels.Logistic models were applied in multiple analysis adjusting for possible confounders.Results: A total of 1 607 patients with T2DM were recruited in our analysis with a mean age of (59.4±8.1) years and an average T2DM duration of (7.0±6.4) years.Among them, 78.3% were on hypoglycemic therapy.The cutoff points of quartiles of VAI were calculated for the males and females, respectively.According to the ascending order of the quartiles of VAI, the participants were divided into four groups, i.e.Q1, Q2, Q3, and Q4.The poor glycemic control rate for these groups were 60.6%, 65.7%, 70.1%, and 71.0%, respectively (Trend χ2=12.20, P<0.001).After adjustment for age, gender, systolic blood pressure (SBP), diastolic blood pressure (DBP), LDL-C, smoking, cardio-cerebral vascular disease (CVD) history, hypoglycemic therapy, T2DM duration, and family history of diabetes, the Logistic regression models showed that the glycemic control rate was significantly associated with VAI levels among the patients with T2DM.Compared with the participants in group Q1, the ORs of poor glycemic control for those in groups Q2, Q3, and Q4 were 1.239 (95%CI 0.918 to 1.672), 1.513 (95%CI 1.117 to 2.050), and 1.535 (95%CI 1.128to 2.088), respectively (trend P=0.003).With each quartile increase in VAI, the OR of poor glycemic control was 1.162 (95%CI 1.054 to 1.282).Conclusion: The glycemic control among the patients with T2DM is significantly associated with VAI.High level of VAI is an indicator of poor glycemic control.

A method of complete acid hydrolysis combined with high performance anion exchange chromatography and pulsed amperometric detection was developed for the monosaccharide composition analysis of arabinoxylan from the seeds of Plantago asiatica L. The parameters including hydrolysis methods, acid types, acid concentration, hydrolysis temperature, hydrolysis time and placement time, which would affect the hydrolysis process, were optimized. The results showed that it would have a better hydrolysis effect for polysaccharide from the seeds of Plantago asiatica L. with 2 mol/L H2 SO4 in an atmospheric oil bath at 120℃for 2 hours. However, the placement time for diluted solution of the hydrolyzed polysaccharide should be less than 6 hours. The polysaccharide was mainly composed of Arabinose (8. 89%) and Xylose (41. 52%) and Galacturonic acid (0. 73%). Glcuronic acid (3. 44%) was detected simultaneously, and there were also trace amounts of Galatose and Glucose. The results were reproducible. Other arabinoxylans from Panicummiliaceum L. shell, Avena sativa L. bran and Hordeum vulgare L. were taken for monosaccharide compositions analysis under the optimal hydrolysis conditions and the analysis results were good. This study would provide a good reference for monosaccharides composition analysis of arabinoxylans from various sources.

Objective To explore sonographic manifestation of fetal malformations of cortical development.Methods From August 2012 to January 2014 three hundred and twenty-five pregnancy women referred to our institution for fetal brain MRI,which were diagnosed or suspected of central nervous system abnormalities by prenatal ultrasound examination.Results In 325 of cases,14 cases (4％) were diagnosed of malformations of cortical development.Ten eases were indicated by prenatal ultrasound,including three cases of heterotopic gray matter,six cases of microcephaly and one case of hemimegalencephaly; four cases were missed by prenatal ultrasound,including two cases of schizencephaly,one case of tuberous sclerosis,and one case of hypoplasia.Conclusions Cortical malformations can be diagnosed by prenatal ultrasonography based on typical imaging characteristics.Prenatal ultrasound combined with MRI is a powerful tool in diagnosing fetal malformations of cortical development.

Through the establishment of implantable medical device information management system, with the aid of the regional joint sharing of resources, we further enhance the implantable medical device traceability management level, strengthen quality management, control of medical risk.
Equipment Design ; Information Management ; instrumentation ; methods ; Prostheses and Implants ; Software Design

ObjectiveTo explore the expression of CD3+ CD8+ human leukocyte antigen (HLA)-A2+T lymphocytes with specificity to the different hepatitis B virus (HBV) peptides in the peripheral blood mononuclear cells (PBMC)from the patients with hepatitis B associated hepatocellular carcinoma (HCC).MethodsThe HLA-A2+ PBMC from four patients with hepatitis B associated HCC were incubated with five HBV/HLA-A2 pentamers respectively,which were HBV sAg (FLLTRILTI),HBV sAg (GLSPTVWLSV),HBV sAg (WLSLLVPFV),HBV core (FLPSDFFPSV),and HBV pol (FLLSLGIHL),as well as anti-CD3-pacific blue and anti-CD8-fluorescein isothiocyanate (FITC).Then,HBV/HLA-A2-CD3-CD8 positive cells were detected by flow cytometry. The monoclonal HBV/HLA-A2-CD3-CD8+ cells were acquired by fluorescenceactivated cell sorter,and cultured and identified by flow cytometry.The anti-HBV specific T lymphocytes were then cultured with HepG2 (HLA-A2+ ) cells and the release of interferon γ (IFN-γ)were determined by enzyme-linked immunosorbent assay (ELISA),Res(a)ltsThe percentage of antiHBV T lymphoeytes with specificity to GLSPTVWLSV in total CD8+ T lymphoeytes from four patients with hepatitis B associated HCC was 1.44％±0.04％,which was higher than those to other four HBV antigen peptides (0.68％±0.08％ of FLLTRILTI,1.06％±0.09％ of FLPSDFFPSV,0.56％ ±0.04％ of FLLSLGIHL,and 0.46％ ±0.08％ of WLSLLVPFV) (t=0.001,P＜0.05).The two lines of monoclonal cell with specificity to GLSPTVWLSV both exhibited high level of IFN-γ expression after incubated with hepatic carcinoma cell line HepG2 (HLA-A2+)with HBV GLSPTVWLSV peptide.ConclusionsCD3+ CD8+ HLA-A2+ cells with specificity to the different HBV peptides exist in PBMC of patients with hepatitis B associated HCC.The expression level depends on HBV antigen peptide sequences and genomic sites.

Objective To investigate the relationship among Helicobacter pylori(H.pylori),CD4 positive cells and CD8 positive cells in gastric mucosa of the AIDS patients with gastritis.Methods Fiftyeight AIDS patients with upper abdominal pain were diagnosed with chronic gastritis through gastroscopy.The gastric biopsies from them were used for H.pylori detection with rapid urease test and Giemsa staining,pathology examination with HE staining,and immunohistochemistry analysis for CD4,CD8 positive cells in Gastric mucosa.And the application of flow cytometry was for the detection of peripheral blood CD4 and CD8 lymphocytes from the patients.Results H.pylori was positive in 26 cases,and negative was in 32 cases.CD8 cell expression in gastric mucosa of the AIDS patients with H.pylori positive was significantly higher than H.pylori negative patients(P＜0.05).There is no difference CD4 cell expression in gastric mucosa between the AIDS patients with H.pylori positive and H.pylori negative patients.Moreover,CD8 positive lymphocytes in gastric mucosa of those patients with H.pyloriinfection were significantly stronger than the CD4 positive lymphocytes.However,the peripheral blood CD4 lymphocytes from the patients with H.pylori infection were more than those from H.pylorinegative patients significantly(P＜0.05).Conclusion The expression level of CD8 cells in gastric mucosal tissues of AIDS patients with H.pylori infection were higher than those without H.pylori infection.The CD4 lymphocytes from the peripheral blood of the patients with H.pylori infection were more than those without H.pylori negative patients.

This study evaluated the efficacy and safety of"J"-shaped uterine incision for caesarean section for patients diagnosed with placenta previa.A total of 55 consecutive cases of placenta previa treated in Union Hospital were retrospectively analyzed over a period of two years and 10 months.The subjects were divided into two groups with respect to the uterine incision.Twenty-four pregnant women with placenta previa who were indicated for caesarean.section underwent the procedure using a new"J"-shaped uterine incision and 31 pregnant women with placenta previa received caesarean section that used the traditional transverse incision.The two groups were compared in terms of operation time,estimated blood loss,infant expulsion time,exhaust time and postoperative recovery.Meanwhile,comparison was also made in neonatal clinical data between the two groups.Compared with the"J"-shaped incision group,the traditional incision group had a lower Apgar scores(P<0.05).However,there existed no statistically significant differences in the overall time of operation and postoperative period of breaking wind(P>0.05).It is concluded that,with caesarean section for placenta previa patients,the"J"-shaped uterine incision significantly decreases intraoperative blood loss and facilitates the fetal delivery.

The underlying effect of different concentrations of neogenin on proliferation,apoptosis and the related proliferative factors in human trophoblasts was explored in order to understand the function of neogenin during placentation.TEV-1 cell line was cultured and the expression of netrin-1was detected by using indirect cellular immunofluorescence.Exponentially growing TEV-1 cells were treated by different concentrations of neogenin(0,1,5,10,50 ng/mL)for 24 h.Cell viability was measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide(MTT)assay.TEV-1 cell apoptosis was assessed by flow cytometry(FCM).The expression of netrin-1 mRNA and protein in TEV-1 cells was examined by using real-time PCR and Western blot,respectively.It was found that immunoreactivity for netrin-1 was observed in cytoplasm of the trophoblasts.Immediately after treatment with different concentrations of neogenin for 24 h,the netrin-1 expression began to increase.Real-time PCR revealed that the expression level of netrin-1 mRNA was 37.59±10.25 times higher than control group when TEV-1 cells were exposed to 50 ng/mL neogenin(P<0.01),and the same tendency was seen by using Western blot.MTT results showed that proliferation of TEV-1 cells was independent of neogenin.Meanwhile,apoptosis was significantly increased to(22.15±6.15)% at50 ng/mL neogenin and(6.55±0.25)% without neogenin(P<0.01).It is suggested that neogenin regulates proliferation and apoptosis of TEV-1 cells.And it can enhance the ability of TEV-1 ceils to express netrin-1 in a dose-dependent manner.Neogenin may play an important biological role in the normal human pregnancy and contribute to the physiological pregnancy process.