Effects of Cr 6+ concentration and culture time on four heavy metal removing strains,stability of these four strains removing Cr 6+,configuration changes inside or outside their cells,effects of Cr 6+ on soluble reductive sugar inside their cells,and effect of several factors on these strains had been studied,and the Cr 6+ resistance mechanisms of these strains have been discussed elementarily. The results showed that the Lethality of these strains caused by Cr 6+ was similar with one another, namely, increasing at first, then decreasing, and finally increasing again as culture time passed. Acclimatization of Candida sp. was better than Sporobolomycetaceae sp.,and the Cr 6+ resistance of Sporobolomycetaceae sp. 7-3 was the best of the four. The research also demonstrated that the metabolic activity of these strains had been influenced by Cr 6+ in a certain extent. Scanning electron microscopy,transmission electron microscopy,and atomic force microscopy observations approved that removal of Cr 6+ by Candida sp. was depended on both surface adsorption and intracellular accumulation. Effects of Cr 6+ concentration, pH, culture time, nitrogen source, carbon source and adsorption time on these strains are not the same.

Objective:To provide microsurgical anatomy data in the course, branch, distribution, arterial network profile of the submental artery and the range of the flap excision in submental flap transplantation.Methods:From March, 2015 to March, 2020, a total of 36 head and neck cast specimens were studied. Acrylic-butadience-styrene plastic (ABS) filler were perfused into the external carotid artery to make cast specimens. The course, branching, distribution and the arterial framework of the submental artery under a surgical microscope were investigated.Results:The submental artery originated from the facial artery before reaching the lower edge of the mandible (1.50±0.50) cm, with a diameter of (1.50±0.85) (0.6-2.3) mm. The main trunk of submental artery was (5.5±0.5) cm in length, which ran forward along the lower edge of the mandible and branched out (9.0±3.0) (7-13) branches with diameters between 0.1-0.5 mm, and mainly distributed to skin and superficial fascia of the submental area. The main trunk of submental artery divided into ascending, horizontal and descending branches about 3.0 cm of the midline of the mandible. The ascending branch went upwards over the lower edge of the mandible and joined up with the lower labial arch or participated in the formation of the lower labial arch; the horizontal branch divided into several branches and joined up with the branches from the opposite side; the descending branch branched posteriorly and inferiorly, joined up with branches of lingual artery and superior thyroid artery. The branches of the submental artery and the branches of the peripheral arteries were joined up in the submental area to form the submental artery network. The diameter of the vessels in the network ranged 0.1-0.2 mm. The arterial network was built in the form of 1 to 3 layers, and the area of main network was about 7.0 cm×5.0 cm.Conclusion:The submental artery has a long trunk, many branches and abundant anastomoses between the branches, forming a dense submental artery network, which provides sufficient pedicle length, rich blood supply and cutting area for submental flap. The flap can be transplanted free or transposed. The best location of submental flap is near the midline of arterial network, and the appropriate area is 7.0 cm×5.0 cm.

【Objective】 To establish a new method for the determination of fibrinogen content in cryoprecipitated antihemophilic factor. 【Methods】 Fibrinogen (Fib) could bind with sheep anti-human fibrinogen (anti-Fib) specifically and further form antigen-antibody complex. When the Fib was present in the solution, the fluorescence of fluorescein isothiocyanate (FITC) labeled on the anti-Fib (FITC-anti-Fib) was quenched due to the formation of immune complex. The fluorescence quenching degree of FITC-anti-Fib was positively correlated with Fib concentration (cFib) in a certain concentration range. 【Results】 The linear relationship between fluorescence quenching degree [(I0-I)/I0] of FITC-anti-Fib and ln(cFib) was (I0-I)/I0=15.53ln(cFib)+ 80.79 (R²=0.99) when the cFib was in the range of (0.007 8-0.560 0) g/L. The recovery of Fib was (96.77-102.43) %. When the method was applied to determine Fib at high, medium, and low concentrations, the obtained intra-day variation coefficients were 0.31%, 0.56%, and 0.49%, respectively, and the inter-day variation coefficients were 3.81%, 3.06%, and 4.13%, respectively. There was no significant difference between the results measured by fluorescence quenching method and coagulation method (t=-0.075, P>0.05). 【Conclusion】 In this work, a new fluorescence method for the determination of Fib in cryoprecipitated antihemophilic factor was successfully established based on the specific combination of fib and FITC-anti-Fib. The method is simple and rapid. The obtained results were accurate and reliable by using this method to determine Fib.

【Objective】 To determine the volume range of suspended erythrocyte and establish its internal control standard. 【Methods】 The theoretical value of suspended erythrocyte volume was calculated according to the screening criteria of healthy blood donors and Quality Requirements for Whole Blood and Blood Components. A total of 2 410 bags of 1 U and 2 U suspended erythrocyte were randomly selected and weighed, and the volume range were formulated by ±2S and ±10% respectively and then compared to determine the volume range in line with the actual situation of our center. 【Results】 The theoretical volume range of 1 U and 2 U suspended erythrocyte were 117-160 mL vs 234-320 mL, and the actual volume range were 142-180 mL vs 276-393 mL. The volume range of 1 U and 2 U suspended erythrocyte formulated by ±2S were 145-181 mL vs 298-358 mL, and by ±10% were 147-179 mL vs 295-361 mL. The hematocrit and hemoglobin content of suspended erythrocyte within the actual volume range met the quality requirements. There were fluctuations in the volume of suspended erythrocyte from different regions. 【Conclusion】 Based on the actual situation of our center and the sampling results of suspended erythrocytes in recent two years, 163 mL±10% and 328 mL±10% were determined as the internal control standards of 1 U and 2 U suspended erythrocyte, respectively. Blood centers should establish accurate and feasible standard of suspended erythrocyte according to the actual situation.

【Objective】 To establish a simple, economical and rapid method for the determination of methylene blue (MB) release in virus inactivation bag. 【Methods】 Based on the fluorescence energy transfer between MB and BSA-stabilized gold nanoclusters (BSA-AuNCs), the standard curve of MB determination was established by measuring the fluorescence quenching degree of MB to BSA-AuNCs in different concentrations to conduct the determination of MB release in virus inactivation bag. 【Results】 There was a good linear relationship between the MB concentration (cMB) and the fluorescence quenching degree of BSA-AuNCs[ (I0-I)/I0=0.018cMB+ 0.021(r=0.996)] when the fluorescence emission wavelength was about 620 nm and the cMB was in the range of (0.9-36) μmoL/L. The recovery of MB was 98.00% -101.95 % when applied to determine MB at high, medium, and low concentrations, the obtained intra-day variation coefficients were 0.73%, 0.81% and 0.77% respectively, and the obtained inter-day variation coefficients were 3.92%, 3.81%, and 4.73% respectively. There was no significant difference between the results measured by this method and those measured by combination of solid-phase extraction and spectrophotometry(P>0.05). 【Conclusion】 The fluorescence energy transfer method could achieve simple and rapid determination of MB release in virus inactivation bag with accurate and reliable results.

OBJECTIVETo observe the effect of ERK1/2 signal pathway activated by SiO₂ in the proliferation of human embryonic lung fibroblast mediated by silicotic alveolar macrophages.

METHODThe alveolar macrophages (AM) harvested from silicotic sufferers by bronchoalveolar lavage (BAL) were interacted with SiO₂ suspension once more. HELF, pretreated with the inhibitor PD98059 (50 µmol/L) for 1 hour, were stimulated by conditional supernatant fluid of silicotic sufferers. The experimentation have been classificated four group: blank group, AM control group, SiO₂ treatment group, PD98059 intervention group. The proliferation activity and expressions of Phospho-ERK1/2 of lung fibroblast activated by AM supernatant fluids of silicotic are detected with the MTT assay, flow cytometry and Western blot method after being pretreatmented with PD98059.

RESULTThe A values of cell proliferation in SiO₂ treatment group and AM control group are 2.6 and 2.0 times that of blank group, in which the difference was statistically significant (P < 0.05). Comparing with SiO₂ treatment group, the A values of every concentrations of PD98059 intervention group decreased with a dose-response relationship, after 10, 25 and 50 µmol/L PD98059 intervention. The 25 and 50 µmol/L PD98059 intervention group were 72.1% and 48.5% of SiO₂ treatment group, which the difference is statistic (P < 0.05). The expression of phospho-ERK1/2 in SiO₂ treatment group was up, which appeared in 15 min and apparent activated in 30 min (A value is 0.4653 ± 0.0265), and then still in the higher state afterwards declined after 60 min. In addition to 15 min, the expression of phospho-ERK1/2 protein in SiO₂ treatment group at each time point are 1.25, 1.23, 1.25 times over the same period AM control group respectively, the differences were statistically significant (P < 0.05).

CONCLUSIONThe silicotic supernatant of alveolar macrophages have promote proliferation of HELF and activation of ERK1/2, which may involve in the development of silicosis pathogenesis by ERK1/2 signal pathway.

Cell Proliferation ; Cells, Cultured ; Culture Media, Conditioned ; Fibroblasts ; drug effects ; metabolism ; Flavonoids ; pharmacology ; Humans ; Lung ; cytology ; drug effects ; Macrophages, Alveolar ; metabolism ; Male ; Middle Aged ; Mitogen-Activated Protein Kinase 1 ; drug effects ; metabolism ; Mitogen-Activated Protein Kinase 3 ; drug effects ; metabolism ; Signal Transduction ; drug effects ; Silicon Dioxide ; pharmacology

OBJECTIVETo study the proliferation effect of the AM supernatant incubated activation of p38 mitogen activated protein kinases (p38MAPK) signal transduction pathway in human embryonic lung fibroblasts, and to participate in the development of fibrosis in silicosis.

METHODSThe silicotic alveolar macrophages were collected by bronchoalveolar lavage and incubated in vitro in the DMEM medium containing SiO₂ (50 µg/ml) and DMEM medium without SiO₂ for 18 h. Then the AM supernatant incubated for 18 h was collected. HELFs were isolated by organize paste block method, and incubated with AM supernatants. HELFs were divided into four groups: blank control groups, AM groups, SiO₂ + AM groups, SB203580 + SiO₂ + AM groups. The proliferation in the HELF was detected with MTT method and Flow cytometry.

RESULTSThe proliferation in the HELF acted with the conditioned AM supernatant fluid were more than blank control groups, AM groups and SB203580 + SiO₂ + AM groups [average optical density: (0.48 ± 0.03) vs (0.29 ± 0.01), (0.38 ± 0.02), (0.33 ± 0.03)], the values with MTT method were statistically different (P < 0.05); Proliferous index with flow cytometry in SiO₂ + AM groups (18.12 ± 0.82) was bigger than blank control groups (9.24 ± 0.48), AM groups (14.76 ± 0.43) and SB203580 + SiO₂ + AM groups (11.71 ± 0.70) and the values were statistically different(P < 0.05).

CONCLUSIONSThe AM supernatant stimulated by silicon dioxide can accelerate the proliferation in the HELF by activation of p38MAPK signal transduction pathway.

Adult ; Cell Proliferation ; Cells, Cultured ; Culture Media, Conditioned ; Fibroblasts ; cytology ; drug effects ; pathology ; Humans ; Lung ; cytology ; MAP Kinase Signaling System ; Macrophages, Alveolar ; cytology ; Male ; Signal Transduction ; Silicon Dioxide ; pharmacology ; Silicosis ; metabolism ; pathology ; p38 Mitogen-Activated Protein Kinases ; metabolism

OBJECTIVETo explore the effects of microcystin-LR (MCLR) on the expression of base excision repair genes and genes related to apoptosis.

METHODSThe BRL-3A cells were exposed to different concentrations of MCLR for various periods of time and the cell viability was measured by MTT. The mRNA expression was determined with the quantitative real-time polymerase chain reaction (QRT-PCR).

RESULTSThe viability of BRL-3A cells significantly reduced in a concentration- and time-dependent manner. In 30 µg/ml group, the mRNA expression level (1.327 ± 0.028) of p53 increased significantly at 24 h after exposure, as compared with the other groups (1.005 ± 0.117, 0.862 ± 0.154, 1.028 ± 0.056 and 1.015 ± 0.091) (P < 0.05). The mRNA expression levels (5.080 ± 0.729, 5.820 ± 0.373, 6.018 ± 0.359 and 6.183 ± 0.515) of Bax in all exposure groups were significantly higher than that (1.024 ± 0.277) in control group at 24 h after exposure. However, the Bax mRNA expression level (0.604 ± 0.146) in the 30 µg/ml group at 72 h after exposure was significantly lower than those (1.004 ± 0.107, 0.811 ± 0.142, 0.855 ± 0.101 and 0.814 ± 0.056) in other groups (P < 0.05). When compared with control group (1.006 ± 0.132) and 1 µg/ml group (1.034 ± 0.241), the mRNA expression level (0.488 ± 0.147) of PARP1 in 30 µg/ml group at 48 h after exposure decreased significantly (P < 0.05). Furthermore, the mRNA expression levels (0.594 ± 0.180, 0.491 ± 0.015 and 0.305 ± 0.091) of JWA, XRCC1 and PARP1 in 30 µg/ml group at 72 h after exposure decreased significantly, as compared with the other groups (P < 0.05).

CONCLUSIONThe induction of gene expression is a transient phenomenon that occurred at different times of exposure for different genes. Inhibition of MCLR on the base excision repair gene expression may play important role in the course of MCLR promoting liver tumor.

Animals ; Apoptosis ; Apoptosis Regulatory Proteins ; genetics ; Base Sequence ; Cell Line ; DNA Repair ; Gene Expression ; Microcystins ; toxicity ; RNA, Messenger ; genetics ; Rats

【Objective】 To detect the anti-SARS-CoV-2 neutralizing antibody levels in convalescent plasma (CP) and to evaluate whether it has specific anti-SARS-CoV-2 S antigen effect, so as to provide laboratory data support for clinical use of CP. 【Methods】 Nine CP donors who have recovered from COVID-19 were studied, and 4 volunteers who completed the vaccination and 3 asymptomatic infected blood donors were compared. Anti-SARS-CoV-2 antibodies including total antibody, IgM and IgG were measured by chemiluminescence microparticle immunoassays (CMIA) test in three groups. The VSV pseudovirus-based neutralization assay for evaluating neutralizing antibodies against SARS-CoV-2 was carried out in all samples. 【Results】 All samples were tested positive by the total antibody and IgG CMIA in COVID-19 CP donors and recipients of inactivated COVID-19 vaccine. High titers of IgG were observed in CP donors and vaccine recipients compared with asymptomatic blood donors. All vaccine recipients and 8 of 9 CP donors tested positive by SARS-CoV-2 pseudovirus-based neutralization test, whereas all asymptomatic blood donors tested negative. 【Conclusion】 The levels and characteristics of neutralizing antibodies among COVID-19 CP donors, vaccine recipients and asymptomatic blood donors were different. When unable to implement the pseudovirus assay to measure neutralizing antibodies, the detection of total antibody can be considered instead.

BACKGROUNDDespite technical advances in tools used to facilitate implantation of cardiac resynchronization therapy (CRT) devices, there are many hurdles related mainly to the variation in the anatomy of the coronary veins. One such difficulty is the presence of a very sharply-angulated or tortuous of the lateral or posterolateral cardiac vein.

METHODSTotally 44 patients, 28 males and 16 females, with congestive heart failure and intraventricular conduction delay were studied retrospectively. There were 23 patients who had left ventricular (LV) lead implantation using standard techniques and equipment. For the other 21 patients with LV lead implantation we used the Attain Select II catheter delivery system. The patients were seen every 3 - 6 months for 12 months and the efficacy of the primary procedure, LV lead implantation time, procedure and fluoroscopy time and the complications associated with the two techniques were evaluated.

RESULTSThere were no significant differences in the age, gender, New York Heart Association (NYHA) functional class, ischemic etiology, QRS duration, left ventricular ejection fraction, left ventricular end-diastolic diameter, left ventricular end-systolic diameter and LV dyssynchrony between the two groups. The LV lead implantation time, procedure time and fluoroscopy time were significantly shorter in the group using the Attain Select II catheter delivery system; LV lead implantation time from (51 ± 7) minutes to (40 ± 7) minutes (P < 0.001), procedure time from (143 ± 17) minutes to (124 ± 18) minutes (P = 0.001), and fluoroscopy time from (45 ± 7) minutes to (35 ± 6) minutes (P < 0.001). A successful procedure of LV lead implantation was significantly improved from 17/23 (74%) patients using the standard techniques and equipment, to 20/21 (95.3%) patients using the Attain Select II catheter delivery system (P = 0.06)

CONCLUSIONIt is feasible and safe to implant LV leads through the coronary sinus using the Attain Select II catheter delivery system.

Aged ; Cardiac Resynchronization Therapy ; methods ; Female ; Heart Failure ; therapy ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Treatment Outcome ; Ventricular Dysfunction, Left ; therapy