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Objective To explore the dynamic expression of programmed cell death-1 (PD-1) and its ligand PD-L1 at the maternal-fetal interface of mice post-infection with Toxoplasma gondii at early pregnancy and examine its interaction with interferon-γ (IFN-γ). Methods A total of 20 mice at day 0 of pregnancy were randomly assigned into 4 groups, including the 12-day pregnancy control group (12 dpn group), 12-day pregnancy and infection group (12 dpi group), 18-day pregnancy control group (18 dpn group) and 18-day pregnancy and infection group (18 dpi group), respectively. On the 6th day of the pregnancy, mice in the 12 dpi and 18 dpi groups were injected intraperitoneally with 150 tachyzoites of the T. gondii PRU strain, while mice in the 12 dpn and 18 dpn groups were injected with the same volume of PBS. All mice in the four groups were sacrificed on 12th and 18th day of the pregnancy, and the number of placenta and fetus was counted and the weight of placenta and fetus was measured. Then, the placental and uterine tissues of the pregnant mice in each group were sampled for pathological examinations. The mRNA expression of PD-1, PD-L1, T. gondii surface antigen SAG-1 and IFN-γ genes was quantified using a quantitative real-time PCR (qPCR) assay, and the correlation between PD-1 and IFN-γ expression was examined. In addition, the 12 dpn group, 12 dpi group, 18 dpn group, 18 dpi group, PBS negative control of the 12 pdi group and PBS negative control of the 18 dpi group were assigned, and the PD-1 expression was determined in the uterine and placenta tissues of the pregnant mice. Results Adverse pregnant outcomes were seen in mice in the 12 dpi and 18 dpi groups, including placental dysplasia and fetal maldevelopment, and the placental weights and fetal body weights were significantly lower in mice in the 12 dpi and 18 dpi groups than those in the 12 dpn and 18 dpn groups (t = 5.52, 11.44, 12.63 and 11.67, all P < 0.01). The histopathological examinations showed that the decidua and junctional regions of the placental tissues were loosely connected in the 12 dpi and 18 dpi groups, and a large number of inflammatory cells infiltration and congestion were seen in the placental and uterine tissues. qPCR assay detected significant differences in PD-1, PD-L1, IFN-γ and SAG-1 expression in the placental and uterine tissues among the 12 dpn, 12 dpi, 18 dpn and 18 dpi groups (F = 22.48, 51.23, 9.61, 47.49, 16.08, 21.52, 28.66 and 238.90, all P < 0.05), and the PD-1, PD - L1, IFN - γ and SAG - 1 expression was all significantly higher in the placental and uterine tissues of mice in the 12 dpi group than in the 12 dpn group (all P values < 0.05). The PD-1 and PD-L1 expression was significantly lower in the placental tissues of mice in the 18 dpi group than in the 18 dpn group (all P values < 0.05), and the IFN-γ and SAG-1 expression was significantly higher in the placental and uterine tissues of mice in the 18 dpi group than in the 18 dpn group (all P values < 0.05), while the PD-1 and PD-L1 expression was significantly lower in the placental and uterine tissues of mice in the 18 dpi group than in the 12 dpi group (all P values < 0.05). Immunohistochemical staining showed PD-1 expression in the inflammatory cells of the placental tissues of mice in the 12 dpi group, and no apparent PD-1 expression in the 18 dpi group, while strongly positive PD-1 expression was found in the uterine epithelium of mice in the 12 dpi group, and mildly strong expression was in the 18 dpi group. In addition, the IFN-γ mRNA expression was positively correlated with the PD-1 mRNA expression in placental (rs = 0.99, P < 0.01) and uterine tissues of mice in the 12 dpi group (rs = 0.97, P < 0.01) and in placental (rs = 0.82, P < 0.01) and uterine tissues of mice in the 18 dpi group (rs = 0.81, P < 0.01). Conclusions Following T. gondii infection at early pregnancy, the PD-1 and PD-L1 expression shows a remarkable rise at middle pregnancy and a reduction at late pregnancy in placental and uterine tissues of mice, which appears the same tendency with IFN-γ expression during the same time period, and PD-1 expression positively correlates with IFN-γ expression. The dynamic expression of PD-1 and PD-L1 on the maternal-fetal interface of mice may be mutually mediated by IFN-γ induced by T. gondii infection.
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Objective To explore the mechanism of the intestinal barrier damage caused by Blastocystis hominis infections in rats. Methods Thirty SD rats were randomly divided into the control group, and the 1-, 3-, 6- and 9-week-infection groups, of 6 rats in each group. Rats in each infection group were orally infected with B. hominis trophozoites at a density of 2 × 108 parasites per rat, and the control group was given an equal volume of phosphate buffered saline solution. The 7-hour urine samples were collected 1, 3, 6 and 9 weeks post-infection for the measurement of the intestinal permeability. Then, rats were sacrificed using the cervical dislocation method, and the cecum specimens were collected for the detection of the intestinal epithelial cell permeability. The expression of tight junction-related Occludin and Claudin - 1 genes and apoptosis-related Bcl - 2 and Bax genes was quantified in cecum epithelial cells using the real-time fluorescent quantitative PCR (qPCR) assay, and cell apoptosis was detected in the rat cecum using the TdT-mediated dUTP nick-end labeling (TUNEL) assay. Results The median urinary lactolose to mannitol ratios were 0.29, 0.72, 0.44, 0.46 and 0.38 in the control group, and the 1-, 3-, 6- and 9-week-infection groups, respectively, and the difference was statistically significant (H = 12.09, P < 0.05). B. hominis invasion and epithelial injury were observed in intestinal epithelial cells of rats infected with B. hominis, and transmission electron microscopy displayed the destruction of tight junctions between intestinal epithelial cells. The relative expression of Occludin, Claudin-1, Bcl-2 and Bax genes was 1.04, 0.62, 0.71, 0.68 and 0.96; 1.03, 0.61, 0.63, 0.76 and 0.86; 1.08, 0.70, 0.75, 0.74 and 1.03; and 1.00, 1.57, 1.33, 1.35 and 1.10 in the control group and the 1-, 3-, 6- and 9-week-infection groups, respectively, and all differences were statistically significant (F = 2.86, 2.85, 3.37 and 4.45, all P values < 0.05). The median number of positive staining cells were 1.00, 13.00, 9.00, 3.50 and 1.00 in rat cecum specimens in the control group, and the 1-, 3-, 6- and 9-week-infection groups, respectively, and the difference was statistically significant (H = 22.95, P < 0.01). Conclusion B. hominis infection may cause an increase in the rat intestinal permeability through triggering the apoptosis of intestinal epithelial cells to destroy the tight junction between intestinal epithelial cells, thereby destroying the intestinal barrier function.
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Objective To investigate the expression and possible role of hypoxia-inducible factor-1 (HIF-1) at the maternal-fetal interface following Toxoplasma gondii infection during early pregnancy. Methods Twenty pregnant C57BL/6 mice, each weighing 16 to 20 g, were randomly divided into 4 groups, including the 12-d control group, 12-d infection group, 18-d control group and 18-d infection group. Mice in the 12-d and 18-d infection groups were injected intraperitoneally with 150 tachyzoites of the T. gondii PRU strain on day 6 of pregnancy, while mice in the 12-d control and 18-d control groups were injected with the same volume of phosphate buffered saline (PBS). Mice in the control and infection groups were sacrificed on days 12 and 18 of pregnancy, and the placental and uterine specimens of the pregnant mice in each group were sampled for pathological examinations. The mRNA expression of HIF-1α, HIF-1β and vascular endothelial growth factor (VEGF) was quantified using quantitative fluorescent real-time PCR (qPCR) assay in the placental and uterine specimens, and the correlation between HIF-1α and VEGF mRNA expression was examined. In addition, and the HIF-1α expression was detected using immunohistochemical staining in the placental and uterine specimens of pregnant mice. Results Compared with the 12-d and 18-d control groups, adverse pregnant outcomes were observed in mice in 12-d and 18-d infection groups, such as teratism and placental dysplasia. HE staining showed swelling and blood stasis of cells, sinusoid reduction and inflammatory cell infiltration in the labyrinth area of the placenta specimens of mice in 12-d and 18-d infection groups relative to 12-d and 18-d control groups, and columnar epithelial cell injury and inflammatory cell infiltration were seen in the mouse uterine specimens in both infection groups. qPCR assay detected significantly higher HIF-1α (F = 132.6, P < 0.05) and HIF-1β mRNA expression (F = 286.9, P < 0.05) in the placental specimens and lower HIF-1α (F = 111.5, P < 0.05) and HIF-1β mRNA expression (F = 55.2, P < 0.05) in the uterine specimens in the 12-d infection group than in the 12-day control group, and significantly lower HIF-1α and HIF-1β mRNA expression was detected in the placental and uterine specimens in the 18-d infection group than in the 18-day control group (F = 215.8, 418.9, 156.8 and 200.1; all P values < 0.05). Significantly lower VEGF-A (F = 426.2, P < 0.05), VEGF-B (F = 104.6, P < 0.05) and VEGF-C mRNA expression (F = 566.9, P < 0.05) in the placental specimens and higher VEGF-A (F = 426.2, P < 0.05), VEGF-B (F = 104.6, P < 0.05) and VEGF-C mRNA expression (F = 566.9, P < 0.05) in the uterine specimens were detected in the 12-d infection group than in the 12-d control group, and higher VEGF-A, VEGF-B and VEGF-C mRNA expression was found in the placental and uterine specimens in the 18-d infection group than in the 18-d control group (F = 521.9, 100.6, 275.9, 224.6, 108.2 and 333.4; all P values < 0.05). Immunohistochemical staining showed strongly and mildly positive HIF-1α expression in the mouse placental labyrinth area in the 12-d and 18-d infection groups relative to 12-d and 18-d control groups, while no HIF-1α expression was detected in mouse uterine specimens. Conclusions HIF-1α expression appears a tendency towards a rise in the second trimester and a reduction in the third trimester in mice following T. gondii infection during early pregnancy, which is contrary to the changing tendency of VEGF-A, VEGF-B, and VEGF-C expression. It is hypothesized that HIF-1α inhibits placental angiogenesis in mice during pregnancy through suppressing VEGF expression, resulting in adverse pregnant outcomes.
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OBJECTIVE: To establish a method for simultaneous quantitative determination of 14 bile acids in human plasma by liquid chromatograohy-tandem mass spectrometry (LC-MS/MS) and to explore the correlation between the hepatotoxicity induced by cyclosporine A and bile acids. METHODS: Plasma samples were extracted by protein precipitation and bile acids were separated on a Waters ACQUITY UPLC HSS T3(2.1 mm×150 mm,1.8 μm) column with a flow rate of 0.3 mL•min-1. The mobile phase was water (containing 4 mmol•L-1 ammonium acetate) and 95% acetonitrile using gradient elution in 15 min. The detection system used an electrospray ion source in negative ion mode. RESULTS: Fourteen bile acids had a good linear relationship, the intra-and inter-assay RSD values were less than 15%, the accuracy was between 87% and 116%, and the extraction recovery rates of the quality was between 101% and 120%. The concentration of cholic acid (CA) was well correlated with cyclosporine A and suggested that bile acids may be associated with the hepatotoxicity induced by cyclosporine A. CONCLUSION: This LC-MS/MS method for quantitatively determining various bile acids in human plasma is convenient, accurate and sensitive and can be used for further basic research in hepatotoxicity caused by cyclosporine A.
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Objective To analyze the heterogeneities of hepatitis B virus ( HBV ) reverse transcriptase domain (RT) gene mutations related to nucleos (t)ide analogues (NAs) resistance.Methods Blood samples from 2765 chronic hepatitis B patients with virological breakthrough or poor drug response treated in Ningbo No .2 Hospital and Ningbo Fourth Hospital from April 2011 to March 2018 were collected . According to the medication status , it was divided into LAM monotherapy group ( n =603 ) , LdT monotherapy group (n=147), ADV monotherapy group (n=68), ETV monotherapy group (n=10) and the sequential or combined drug resistance of NAs group (n=365).The resistance mutation sites and drug resistance patterns (pathways) of each group were analyzed .The SPSS 19.0 software was used to analyze the data.Results Among 2765 serum samples, the NAs-related HBV-RT resistance mutations were detected in 1193 cases with an overall mutation rate of 43.15％.The mutation rate of LAM monoclonal resistance group was 62.62％ (603/963) with 19 mutation types, the most common single point mutation was rtM204I/V (40.30％, 243/603).The mutation rate of LdT monoclonal resistance group was 45.51％(147/323), and there were 3 mutation types, with the single point mutation rtM204I/V being the most common (59.86％, 88/147).The mutation rate of the ADV monoclonal resistance group was 17.80％(68/382), mainly rtA181T single point mutation (64.71％, 44/68).The mutation rate of the ETV monoclonal resistance group was 4.06％(10/246), and the single point mutation of rtT184A/G/S/I/L/F was the most common one (80.00％, 8/10).The mutation rate of the sequential or combination therapy group was 41.91％ (365/871), among which the mutation rate of the LAM/LdT poor response or the resistance with the sequential ADV group was 63.39％(142/224), and the most single mutation point was rtA181V/T ( 35.21％, 50/142 );the mutation rate of LAM/LdT poor response or drug-resistant with combined ADV group was 42.19％ (54/128), and the most common mutation point was rtA181V/T (46.30％, 25/54);the mutation rate of LAM/LdT with poor response or resistance after sequential ETV 1.0 mg was 44.66％(117/262), and the most common mutation point was rtL180M+M204I/V+S202G/I (31.62％, 37/117);the LAM/LdT poor response or the drug-resistant ETV combined with ADV group had a mutation rate of 7.14％(5/70), all of which were multi-site mutations;the mutation rate of poor response to ADV or resistant with sequential ETV 0.5 mg group was 28.14％(47/167), all of which were multi-site mutations.Secondary ( compensation ) sites such as rtV173L, rtL180M, and rtV214A, and single-point mutations such as rtV207I/L/G, rtS213Tand rtN238T, which were not fully defined , were detected.The resistance patterns ( pathways ) of NAs monotherapy were relatively simple , and the resistance patterns ( pathways ) of NAs experienced patients ( sequential or combined treatment group ) were complex and diverse, and multiple resistance patterns (pathways) existed, along with NAs increasing in species.Non-first-line NAs-related resistance patterns ( pathways ) showed an overall downward trend sand ETV-related drug-resistant mutation showed an overall upward trend .Conclusion The NAs-related HBV resistance mutation sites ( patterns ) are complex and diverse , especially multi-site mutations , refractory drug resistance mutations, multidrug resistance mutations and cross-resistance mutations.Therefore, the optimization of antiviral treatment strategies and drug resistance management concepts need to be continuously updated .
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Objective To understand the prevalence and risk factors of healthcare-associated infection(HAD,and provide evidence for prevention and control of HAI.Methods A cross-sectional survey was adopted,bedside survey and medical record reviewing method was combined to investigate and analyze the prevalence of HAI in a tertiary first-class hospital in 2012-2015.Results A total of 4 725 hospitalized patients were surveyed,the prevalence rates in 2012-2015 were 6.00％,4.77％,3.93％,and 3.05％ respectively,difference was significant(P＜0.05);antimicrobial usage rates were 30.56％,33.82％,32.84％,and 34.48％ respectively,difference was not significant (P＞0.05);the main infection site was lower respiratory tract (43.00 ％),followed by surgical site (16.43 ％);the risk factors for HAI were age ≥65 years,chronic systemic diseases(diabetes,cirrhosis,chronic renal failure,chronic lung disease),immunodeficiency(white blood cell＜1.5 × 109/L),coma,tracheotomy,and mechanical ventilation.Conclusion Survey on HAI prevalence can promote continuous improvement of HAI management,surveillance on surgical site infection and risk factors of HAI should be strengthened.
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Objective To analyze the correlation between liver pathology and clinical characteristics in a large series of patients with chronic HBV infections , so as to provide the data base for non-invasive medical diagnosis .Methods Liver pathology and clinical characteristics of 1 397 patients with chronic HBV infections were retrospectively analyzed . Ridit analysis and Spearman correlation analysis were performed to investigate the correlations of clinical characteristics with liver pathology of patients .Results In 1 397 patients, there were 604 patients (43.24%) with liver inflammation grading ≥G2 and 504 patients (36.08%) with fibrosis stage ≥S2.Inflammation grade and fibrosis stage of liver tissues were both higher in male patients than those in females (u=3.093 and 2.854, P30-40 years and >40 years (r=0.259 and 0.303, P0.05),but there was significant difference in liver fibrosis in patients between aged >40 years and ≤30 years ( F=3.177,P30 years, lightly elevated ALT levels , HBeAg(-) and detectable HBV DNA levels , especially in male patients .Screening for liver fibrosis should be considered in patients with HBeAg ( -) and low HBV DNA levels .
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Objective To evaluate the significance of human papillomavirus L1 capsid protein (HPVL1) and human telomerase RNA component (hTERC) gene in the cytologic specimens of cervix which was infected by the high-risk types of human papillomavirus (HR-HPV),and to expose their relationship with cervical lesions.Methods The fluorescence signal of cytologic samples of cervix were detected by interphase FISH in chromosome enumeration double-color DNA probes TERC.The expression of HPVL1 capsid protein was detected by MaxVision immunohistochemistry method.300 samples were analyzed with HR-HPV positive from the cervical biopsy.The diagnoses as normal or chronic inflammation (n =45),cervical intraepithelial lesions Ⅰ grade (CIN Ⅰ,n =95),CIN Ⅱ (n =58),CIN Ⅲ (n =64),and squamous cervical cancer (SCC,n =37).Results The percentage of HPVL1 positive rates in normal or chronic inflammation,CIN Ⅰ,CIN Ⅱ,CIN Ⅲ and SCC groups were 58.70 ％ (27/46),63.16 ％ (60/95),37.93 ％ (22/58),10.94 ％ (7/64) and 0 (0/37),respectively.The percentage of HPVL1 decreased along with the increase of severity of the cervical intraepithelial lesions.Genomic amplification of hTERC positive rates in normal or chronic inflammation,CIN Ⅰ,CIN Ⅱ,CIN Ⅲ and SCC groups were 6.52 ％ (3/46),11.58 ％ (11/95),51.72 ％ (30/58),85.94 ％ (55/64) and 100.00 ％ (37/37),respectively.The percentage of hTERC increased along with the severity of the cervical intraepithelial lesions (rs =0.302,P ＜ 0.01).The percentage of HPVL+/hTERC-was 57.89 ％ in CIN Ⅰ group and 4.69 ％ in CIN Ⅲ group.The percentage of HPVL-/hTERC+ was 6.32 ％ in CIN Ⅰ group and 79.69 ％ in CIN Ⅲ group.Conclusion The detection of HPVL1 and hTERC are important for assisting cervical lesions screening and monitoring of disease progression in the HR-HPV positive cytologic specimens.
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Objective: To study the anti-influenza A virus effect of theaflavin derivatives which contain theaflavin (TF1), theaflavin-3-gallate (TF2A), theaflavin-3'-gallate (TF2B), and theaflavin-3, 3'-digallate (TF3) and to investigate the mechanism. Methods: The inhibition of theaflavin derivatives on A/Thailand/Kan353/2004 H5N1 pseudovirus was investigated using pseudotype H5N1 virus system. Hemagglutination inhibition assay and neuraminidase (NA) inhibition assay were used to investigate the mechanism for their anti-influenza activities. The inhibition of theaflavin derivatives on influenza A virus FM_1 was observed by H1N1 FM_1 system. Cytotoxicity of theaflavin derivatives on MDCK cells was determined by MTT assay. Results: Theaflavin derivatives could significantly inhibit the infection of pseudovirus H5N1 with IC50 of (151.88 ± 18.95) μg/mL. It had no inhibition on HA1 subunit. Theaflavin derivatives had the inhibition on NA with IC50 of (129.09 ± 1.33) μg/mL. Theaflavin derivatives showed a significant inhibitory activity on FM_1 influenza virus strain in MDCK cells. Theaflavin derivatives showed the low cytotoxicity on MDCK cells with CC50 of (879.89 ± 4.54) μg/mL. Conclusion: Theaflavin derivatives could inhibit the infection of avian influenza virus through the combination with hemagglutinin (HA) HA2 subunit and inhibit the activity of viral NA to some extent, which indicates that the anti-H5N1 avian influenza virus of theaflavin derivatives may be through multi-targets.
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The aim of this study is to investigate the critical factor affecting the properties of PLGA microspheres fabricated by a solid-in-oil-in-water (S/O/W) emulsion technique with BSA as a model protein. Prior to encapsulation, the BSA microparticles were fabricated by a modified freezing-induced phase separation method. The microparticles were subsequently encapsulated into PLGA microspheres by S/O/W emulsion method, then Motic BA200 biological microscope, confocal laser scanning microscope, scanning electron microscope were used to observe the structure of S/O/W emulsion and PLGA microspheres. The protein content extracted or released from BSA microspheres was measured by Bradford protein assay method. It was found that NaCl added in the outer aqueous phase effectively suppressed material exchange between the inner and outer phase of S/O/W emulsion. Then, the structure and permeability of obtained microspheres were influenced. As a result, with the increase of NaCl concentration in the outer aqueous phase, the encapsulation efficiency of microspheres significantly increased from 60% to more than 85%, the burst release of microspheres reduced from 70% to 20%, and the particle size decreased from 103 microm to 62 microm. Furthermore, the rehydration of encapsulated protein was also retarded and then integrity of BSA was successfully protected during encapsulation process. In vitro release test showed that BSA released from PLGA microspheres in a sustained manner for more than 30 days.
Subject(s)
Delayed-Action Preparations , Drug Compounding , Emulsions , Chemistry , Lactic Acid , Chemistry , Microscopy, Confocal , Microscopy, Electron, Scanning , Microspheres , Oils , Particle Size , Polyglycolic Acid , Chemistry , Serum Albumin, Bovine , Chemistry , Sodium Chloride , Chemistry , WaterABSTRACT
<p><b>OBJECTIVE</b>To develop a new nonisotopic detection method of enzyme-amplified time-resolved fluorescence (EATRF) or enzyme-amplified lanthanide luminescence (EALL) for nucleic acid hybridization assays, which can be applied extensively in clinical diagnosis.</p><p><b>METHODS</b>The method combines the high affinity of biotin-streptavidin system, amplification of enzyme, and inherent advantage of lanthanide chelate with the background elimination of time-resolved fluorescence detection. The conversion of 5-fluorosalicyl phosphate to 5-fluorosalicylic acid (5-FSA) by alkaline phosphatase. The salicylic acid product forms a luminescent ternary chelate with Tb3+ and EDTA.</p><p><b>RESULTS</b>The dynamic range of the standard curve of EATRFA for nucleic acid hybridization assay was very wide, the range was more than third order of magnitude. The detection sensitivity was about 10 pg of target sequence. When the known target sequence was 20, 10 and 2 ng, the ratio of measured amount to known amount was 110%, 90% and 115% respectively. The main experimental conditions, for example, the irradiating time of ultraviolet rays, the concentrations of biotinylated probe, AP-SA, 5-FSAP and Tb-EDTA and the methods of washing in the related steps, have been optimized. A new stable technology of fluorescence has been developted.</p><p><b>CONCLUSIONS</b>EATRF detection for nucleic acid hybridization assays is a new sensitive simple method, which has a great prospect.</p>