[Research on quantitative evaluation of revise requirements of Specifications of Air Sampling for Hazardous Substances Monitoring in the Workplace (GBZ 159-2004)].

Objective: To conduct quantitative evaluation on the revise requirements of Specifications of Air Sampling for Hazardous Substances Monitoring in the Workplace (GBZ 159-2004) , clarify the problems and suggestions during its implementation for improvement, and provide a basis for the revision of the standard. Methods: From April to September 2021, stratified convenient sampling method was adopted and semi-open questionnaire was used to investigate the occupational health personnel in CDC, occupational prevention and control institutes, employers, third-party technical service institutions and universitie. The entropy weight of each index and the score based on entropy weight of GBZ 159 were calculated. Spearman rank correlation analysis was used to describe the correlation between the two indexes and radar chart was drawn for comprehensive evaluation. Results: A total of 151 questionnaires were received from the respondents, of which 147 were valid, with an effective recovery rate of 97.35%, involving 29 provinces, autonomous regions and municipalities. The median G scores of the necessity and urgency of GBZ 159 revision based on entropy weight were 2.84 and 3.17, respectively, and the difference was statistically significant (M=-25.50, P<0.001) . The trend of the score G of necessity and urgency based on entropy weight was basically the same for all secondary items (r(s)=0.9998, P<0.001) , and the score G of urgency based on entropy weight was higher than that of necessity. The highest score G of necessity and urgency based on entropy weight was "3.13 long time sampling", which were 7.56 and 8.23 respectively. This was followed by "3.12 short time sampling", which were 7.19 and 7.13 respectively. Conclusion: GBZ 159 has encountered some new problems and challenges in the implementation process, and some of its technical indicators have been out of line with the actual practice of occupational health at present. These are the two items that urgently needs to be revised and improved, such as "3.13 long time sampling" and "3.12 short time sampling" and other items need to be revised and improved.

[Study on the implementation effect evaluation of Specifications of Air Sampling for Hazardous Substances Monitoring in the Workplace (GBZ 159-2004)].

Systematically evaluate the implementation of Specifications of Air Sampling for Hazardous Substances Monitoring (GBZ 159-2004) , so as to provide technical basis for the future standard revision. The semi-structured interview method was used to interview the industry experts from centers for disease control and prevention, occupational disease prevention and control hospitals/institutes, employers, third-party technical service institutions and universities, and the induction method was used to refine the topics and relevant suggestions. Some technical indicators of GBZ 159 are not suitable for the current actual work of occupational health, and need to be revised and improved urgently. The revised GBZ 159 should comply with the current situation of China's industrial development and the development of occupational health testing equipment in the new era, and improve the relevant technical requirements of sampling quality control.

[Epidemiological characteristics of local COVID-19 epidemics and control experience in routine prevention and control phase in China].

The COVID-19 pandemic is still ongoing in the world, the risk of COVID-19 spread from other countries or in the country will exist for a long term in China. In the routine prevention and control phase, a number of local COVID-19 epidemics have occurred in China, most COVID-19 cases were sporadic ones, but a few case clusters or outbreaks were reported. Winter and spring were the seasons with high incidences of the epidemics; border and port cities had higher risk for outbreaks. Active surveillance in key populations was an effective way for the early detection of the epidemics. Through a series of comprehensive prevention and control measures, including mass nucleic acid screening, close contact tracing and isolation, classified management of areas and groups at risk, wider social distancing and strict travel management, the local COVID-19 epidemics have been quickly and effectively controlled. The experiences obtained in the control of the local epidemics would benefit the routine prevention and control of COVID-19 in China. The occurrence of a series of COVID-19 case clusters or outbreaks has revealed the weakness or deficiencies in the COVID-19 prevention and control in China, so this paper suggests some measures for the improvement of the future prevention and control of COVID-19.

[Prognostic significance of different IDH mutations and accompanying gene mutations in patients with acute myeloid leukemia].

Objective: To investigate the prognostic significance of different IDH mutations and accompanying gene mutations in patients with non-M(3) acute myeloid leukemia (AML) . Methods: Second-generation sequencing was performed to detect the mutations of 22 genes in 389 patients with AML in the First Affiliated Hospital of Zhengzhou University from June 2016 to December 2018, and Kaplan-Meier and Cox regression models were used to analyze the prognostic factors. Results: The mutation frequency of IDH1 and IDH2 was 6.2% and 8.7% , respectively, in all patients without co-mutation. The IDH2 mutant group had an older age, higher proportion of bone marrow primitive cells, more common normal karyotype, and more common RUNX1 and SRSF2 mutations compared with IDH2 wild-type group. Univariate analysis of variance showed that the median OS and PFS of IDH1 mutation group were significantly shorter than those of the wild-type group (P<0.05) . IDH2 mutation as a single variable and IDH2R140 mutation had no significant effect on the prognosis, while different mutation sites had different effects. Compared with the IDH2 wild-type group, the IDH2R172 mutation group had lower complete remission (CR) rate and shorter median OS and PFS (P<0.05) . In patients with normal karyotypes or aged ≥50 years, IDH2 mutation as a single variable had no significant effect on the prognosis, IDH1 mutation and IDH2R172 mutation were associated with poor OS and PFS (P<0.05) , and IDH2R140 mutation had no significant effect on OS and PFS. Approximately 74.1% (43/58) of patients with IDH mutation simultaneously carried other gene mutations; however, the number of accompanying gene mutations had no significant effect on the prognosis. Among 58 patients with IDH mutation, the CR rate of patients with NPM1 mutation was significantly higher than that of patients in the NPM1 wild-type group (81.8% vs 36.4% , P=0.014) , the median OS in patients with DNMT3A mutation was lower than that of patients with DNMT3A wild type [4.0 months (95% CI 3.8-4.2) vs 6.3 months (95% CI 2.4-10.2) , P=0.041) ]. Multivariate analysis showed that age ≥60 years and white blood cell count ≥100×10(9)/L were independent risk factors for OS and PFS, while CR after two courses of treatment and hematopoietic stem cell transplantation were independent prognostic favorable factors for OS and PFS. Conclusion: In patients with AML (non-M(3)) , IDH gene mutations often coexisted with other gene mutations, and different subtypes and accompanying gene mutations of IDH have different prognostic significance.

[Clinical features and prognostic factors in adult acute myeloid leukemia patients with FLT3-ITD and CEBPA gene co-mutation].

Objective: To investigate the clinical characteristics and prognosis in adult acute myeloid leukemia (AML) patients with FLT3-ITD and CEBPA double-mutated (CEBPAdm) co-mutation. Methods: Clinical data and prognostic factors were retrospectively analyzed in adult AML patients with FLT3-ITD and CEBPAdm co-mutation at The First Affiliated Hospital of Zhengzhou University from January 2016 to September 2018. Results: Among 599 non-acute promyelocytic leukemia (APL) patients, 268 received gene mutation detection, who were divided into 4 groups including 19 FLT3-ITD positive (FLT3-ITD(+)) and CEBPAdm positive (CEBPAdm(+)) cases (group A) , 84 FLT3-ITD(+) and CEBPAdm(-) cases (group B) , 95 FLT3-ITD(-) and CEBPAdm(+) cases (group C) , 70 double negative mutation cases (group D) . Gender, platelet count, FAB classification, induction treatment regimen and fusion gene mutation were comparable among four groups (P>0.05) , while age onset, peripheral white blood cell (WBC) count, hemoglobin, percentage of blasts in peripheral blood, percentage of blasts in bone marrow, complete remission rate (CR(1) rate) after the first induction chemotherapy, the relapse rate, the median progression-free survival (PFS) time, and median overall survival (OS) time were significantly different between groups (P<0.05) . When compared in pairs, gender, age onset, hemoglobin, platelet count, FAB classification in group A were not statistically different compared to group B, C and D (P>0.05) , while patients in group A had higher WBC count, blasts in peripheral blood, minimal residual disease (MRD) in bone marrow. The CR(1) rates of group A, B, C, and D were 50.0%、32.4%、59.8%、39.0% respectively (P=0.003) , and the relapse rates were 55.6%, 50.0%, 21.1%, 40.0% (P<0.001) . As to survival, the median OS in each group was 6.25, 3.0, 15.5, 10.5 months respectively (P<0.001) , and the median PFS was 5.0, 4.0, 10.0, 6.7 months (P=0.032) . Conclusion: Adult AML patients with FLT3-ITD and CEBPAdm co-mutation have a higher leukemia load and low CR(1) rate, which translates into poor prognosis with high relapse rate and short survival time.

[The Role of TSP-1-CD47 in ROS-mediated Pulmonary Fibrosis Induced by Paraquat].

Objective: Taking human A549 cells as the research object, to construct the paraquat-induced pulmonary fibrosis model in vitro, and to explore the role of TSP-1 (Thrombospondin-1, TSP-1) and its receptor CD47 in PQ-induced pulmonary fibrosis. Methods: Human A549 cells were cultured in vitro, divided into normal control group, PQ group, Anti-TSP1 group (PQ with neutralizing anti-TSP1 antibody at a final concentration of 10 µg/ml) . A549 cells were stimulated with different concentrations (50, 100, 200, 400, 600, 800, 1 000 µmol/L) for different time (12, 24, 48 h) , and then CCK8 method was used to detect the cell viability to screen out the concentration and time of half cell viability. The subsequent test will be performed at this concentration point.The morphology of the cells was observed under inverted microscope. The expression levels of Fibronectin (FN) and type I collagen were determined by Enzyme Linked Immunosorbent Assay (ELISA) . Immunocytochemistry (ICC) and Immunofluorescence (IF) were used to observe the expression of TSP-1 and CD47 protein and the co-expression.The mRNA expression of TSP-1 and CD47 was detected by Real Time PCR (RT-PCR) . The protien expression of TSP-1 and CD47 was detected by Western Blot (WB) . The levels of Reactive Oxygen Species (ROS) were measured by flow cytometry. Results: Before neutralizing anti-TSP1 antibody intervention: (1) When the time of PQ was constant, the cell viability decreased with the increase of PQ concentration. (2) The cells in the control group were closely connected, cobble-like, arranged neatly; with the increase of PQ concentration, the cell gap of PQ group gradually increased, spindle shape or long spindle shape. (3) With the increase of PQ concentration, the relative expression of FN and I collagen in PQ group was gradually increased compared with the control group in a concentration-dependent manner, and 200 µmol/L is the most obvious. (4) Compared with the control group, the mRNA level and the protein expression of TSP-1 and CD47 in PQ group was significantly increased, and 200 µmol/L is the most obvious, and Immunofluorescence showed they were co-expression in cytoplasm. (5) Compared with the normal group, the level of ROS in A549 cells was significantly increased at 24 h after PQ stimulation. (6) Compared with PQ group, the cell viability of Anti-TSP1 group was significantly increased, and the morphology changed to normal cell morphology, and the mRNA level and the protein expression of TSP-1 and CD47 decreased, and the overexpression of ROS was inhibited, and the relative expression of FN and I collagen decreased. Conclusion: PQ stimulation induced morphological changes of A549 cells, increased expression of TSP-1, CD47, FN and type I collagen, and increased production of ROS.Neutralizing anti-TSP1 antibodies against TSP-1 can partially improve the above lesions. TSP-1-CD47 may be associated with oxidative stress-mediated PQ-induced pulmonary fibrosis.

[The roles of TSP-1 and its receptor CD47 in pathogenesis of paraquat-induced pulmonary fibrosis in rats].

Objective: To establish a rat model of paraquat (PQ) -induced pulmonary fibrosis and observe the changes in thrombospondin-1 (TSP-1) and its receptor CD47 in lung tissue, and to investigate their roles in the pathogenesis of PQ-induced pulmonary fibrosis. Methods: Fifty-four clean adult male Sprague-Dawley rats were randomly divided into normal control group (n=6) and 2 h, 12 h, 1 d, 3 d, 7 d, and 14 d PQ poisoning groups (n=8 per group). A rat model of PQ poisoning was established by a single gavage of 20 wt.% PQ solution (50 mg/kg). Flow cytometry was used to determine the concentration of reactive oxygen species (ROS) in blood and lung tissue. Enzyme-linked immunosorbent assay was used to determine the concentrations of hydroxyl radicals, malondialdehyde, and hydroxyproline in lung tissue. HE staining and Masson staining were used to observe the pathological damage of lung tissue after PQ poisoning. The expression of TSP-1 and CD47 in lung tissue was measured by Immunohistochemistry. Results: Compared with the normal control group, the 2 h to 7 d PQ poisoning groups showed significant increases in ROS fluorescence intensity in red blood cells and lung tissues and the concentrations of malondialdehyde and hydroxyl radicals in lung tissue (P<0.05) , and the 14 d PQ poisoning group had a significant increase in the concentration of hydroxyproline in lung tissue (P<0.05). HE staining showed that the 2 h to 7 d PQ poisoning groups had significantly higher semiquantitative pathological scores of pulmonary alveolitis than the normal control group (P<0.05). The Masson staining showed that the 7 d and 14 d PQ poisoning groups had significantly higher semiquantitative pathological scores of pulmonary fibrosis than the normal control group (P<0.05). Compared with the normal control group, all PQ poisoning groups (except the 12 h group) had significantly increased expression of TSP-1 in lung tissue (P<0.05) , and all PQ poisoning groups (except the 1 d group) had significantly increased expression of CD47 in lung tissue (P<0.05). Within 2 h after PQ poisoning, the expression of TSP-1 and CD47 was positively correlated with the concentrations of ROS, hydroxyl radicals, and malondialdehyde and the degree of pulmonary alveolitis (P<0.01) ; at 1 d after PQ poisoning, the expression of TSP-1 and CD47 was positively correlated with the concentration of hydroxyproline in lung tissue (P<0.01) . Conclusion: The expression of TSP-1 and CD47 is closely related to oxidative stress and subsequent pulmonary fibrosis, and they may be involved in the development and progression of pulmonary alveolitis and subsequent pulmonary fibrosis in rats with PQ poisoning.

[Influence of two positions for measuring instrument adapter on measurement of hand-transmitted vibration in grinding machine].

OBJECTIVE: To investigate the influence of two positions for measuring instrument adapter on the measurement of hand-transmitted vibration in grinding machine using the intraclass correlation coefficient (ICC) of reliability assessment index, and to provide a basis for studies on the measurement standard for hand-transmitted vibration. METHODS: With reference to the measurement standard for hand-transmitted vibration ISO 5349 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-Part 1: General requirements and Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-Part 2: Practical guidance for measurement at the workplace, the domestic AWA5936 hand-transmitted vibration measuring instrument and SVAN-106 hand-transmitted vibration measuring instrument from Poland were used to measure hand-transmitted vibration in 3 workers for grinding machine in a foundry for 5 days continuously from September to October, 2014, and Y-axis data were recorded and compared. RESULTS: In worker A, the "T" -shaped adapter had a significantly higher mean Y-axis accelerated speed effective value than the "O" -shaped adapter [4.34 m/s(2) (95%CI 4.05(-)4.63) vs 2.32 m/s(2) (95%CI 2.27~2.38) , t=13.781, P<0.01]. In workers B and C, AWA5936 "U" -shaped adapter (placed at the position of the handle of grinding machine) had lower degrees of data variation of 12.55% and 15.77%, respectively, suggesting good data stability. The measurement results showed significant differences across different positions of adapter (P<0.01) and between all adapters except "O" -shaped and line-shaped adapters (all P<0.01) , while the measurement results showed no significant differences between the "O" -shaped and line-shaped adapters (P>0.01). The comparison of the measurement results of AWA5936 vibration measuring instrument with an "U" -shaped adapter and SVAN-106 vibration measuring instrument with an "S" -shaped adapter showed an ICC of >0.80 (ICC=0.82) , while the comparison of the measurement results of AWA5936 vibration measuring instrument with an "O" -shaped adapter and SVAN-106 vibration measuring instrument showed an ICC of <0.40. CONCLUSION: SVAN-106 vibration measuring instrument with an "S" -shaped adapter placed at the palm and AWA5936 vibration measuring instrument with an "U" -shaped adapter placed at the handle of grinding machine can give comparable measurement results with good reliability.

[Measurement and analysis of hand-transmitted vibration of vibration tools in workplace for automobile casting and assembly].

OBJECTIVE: To investigate the features of hand-transmitted vibration of common vibration tools in the workplace for automobile casting and assembly. METHODS: From September to October, 2014, measurement and spectral analysis were performed for 16 typical hand tools(including percussion drill, pneumatic wrench, grinding machine, internal grinder, and arc welding machine) in 6 workplaces for automobile casting and assembly according to ISO 5349-1-2001 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-part 1: General requirements and ISO 5349-2-2001 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-Part 2: Practical guidance for measurement in the workplace. RESULTS: The vibration acceleration waveforms of shearing machine, arc welding machine, and pneumatic wrench were mainly impact wave and random wave, while those of internal grinder, angle grinder, percussion drill, and grinding machine were mainly long-and short-period waves. The daily exposure duration to vibration of electric wrench, pneumatic wrench, shearing machine, percussion drill, and internal grinder was about 150 minutes, while that of plasma cutting machine, angle grinder, grinding machine, bench grinder, and arc welding machine was about 400 minutes. The range of vibration total value(ahv) was as follows: pneumatic wrench 0.30~11.04 m/s(2), grinding wheel 1.61~8.97 m/s(2), internal grinder 1.46~8.70 m/s(2), percussion drill 11.10~14.50 m/s(2), and arc welding machine 0.21~2.18 m/s(2). The workers engaged in cleaning had the longest daily exposure duration to vibration, and the effective value of 8-hour energy-equivalent frequency-weighted acceleration for them[A(8)] was 8.03 m/s(2), while this value for workers engaged in assembly was 4.78 m/s(2). The frequency spectrogram with an 1/3-time frequency interval showed that grinding machine, angle grinder, and percussion drill had a high vibration acceleration, and the vibration limit curve was recommended for those with a frequency higher than 400 min/d. CONCLUSION: The workers who are engaged in cleaning, grinding, and a few positions of assembly and use grinding machine, angle grinder, internal grinder, and percussion drill are exposed to vibrations with a high vibration acceleration and at a high position of the frequency spectrum. The hand-transmitted vibration in the positions of cutting, polishing, and cleaning in automobile casting has great harm, and the harm caused by pneumatic wrench in automobile assembly should be taken seriously.

Chemically specific imaging of cryptosporidium oocysts using coherent anti-Stokes Raman scattering (CARS) microscopy.

We demonstrate the application of coherent anti-Stokes Raman scattering microscopy for the rapid, label-free chemical imaging of waterborne pathogens. Chemically selective images of cryptosporidium were acquired in just a few seconds using coherent anti-Stokes Raman scattering microscopy, demonstrating its capability for the rapid detection of cryptosporidium at the single oocyst level. We discuss the applicability of such a technique in a near-real time automated water testing system.

The vacuolar-ATPase B1 subunit in distal tubular acidosis: novel mutations and mechanisms for dysfunction.

Mutations in the B1 subunit of the multisubunit vacuolar ATPase cause autosomal-recessive distal renal tubular acidosis and sensorineural deafness. Here, we report a novel frameshift mutation that truncates the C-terminus of the human B1 subunit. This mutant protein failed to assemble with other subunits in the cytosol to form the complex that can be targeted to vesicular structures in mammalian cells. Loss of proton pump activity was demonstrated in a functional complementation assay in B-subunit null yeast. The mutation caused loss of a discreet C-terminal region critical for subunit interaction not related to the C-terminal PDZ motif. Co-expression studies failed to demonstrate dominant negative effects of this truncated mutant over wild-type B1. Analysis of 12 reported B1 subunit missense mutations showed one polymorphic allele had intact pump function, two point mutants had intact assembly but defective proton pumping, and the remaining nine had disrupted assembly with no pump function. One presumed polymorphic allele was actually an inactivating mutation. Our study shows that multiple mechanisms of pump dysfunction result from B1 subunit mutations with a common outcome being defective assembly. Polymorphisms of the B1 subunit in the general population may affect renal acidification and urinary chemistry.

Phase manipulated multi-beam holographic lithography for tunable optical lattices.

We present principle and technique to actively stabilize and control the phase differences between multi-laser beams that produce stable and adjustable intensity patterns. This technique is based on a novel optical set-up and on a closed loop control over the phase difference between each pair of the input laser fields. Tunable optical lattices are demonstrated by exciting FeTPPCl-doped liquid crystals with the variable intensity patterns.

Three-dimensional imaging of chemical bond orientation in liquid crystals by coherent anti- Stokes Raman scattering microscopy.

Liquid crystals are a class of industrially important materials whose optical properties make them useful particularly in display technology. Optical imaging of these materials provides information about their structure and physical properties. Coherent anti-Stokes Raman scattering (CARS) microscopy is used to provide three-dimensional chemical maps of liquid crystalline samples without the use of external labels. CARS is an optical imaging technique that derives contrast from Raman-active molecular vibrations in the sample. Compared to many other three-dimensional imaging techniques, CARS offers more rapid chemical characterization without the use of external dyes or contrast agents. The use of CARS to image chemical and orientational order in liquid crystals is demonstrated using several examples, and the limitations and benefits are discussed.

Adaptive optics for enhanced signal in CARS microscopy.

We report the use of adaptive optics with coherent anti-Stokes Raman scattering (CARS) microscopy for label-free deep tissue imaging based on molecular vibrational spectroscopy. The setup employs a deformable membrane mirror and a random search optimization algorithm to improve signal intensity and image quality at large sample depths. We demonstrate the ability to correct for both system and sample-induced aberrations in test samples as well as in muscle tissue in order to enhance the CARS signal. The combined system and sample-induced aberration correction increased the signal by an average factor of approximately 3x for the test samples at a depth of 700 microm and approximately 6x for muscle tissue at a depth of 260 microm. The enhanced signal and higher penetration depth offered by adaptive optics will augment CARS microscopy as an in vivo and in situ biomedical imaging modality.

Towards CARS Endoscopy.

We provide a proof-of-principle demonstration of CARS endoscopy. The design utilizes a single mode optical fiber with a focusing unit attached to the distal end. Picosecond pump and Stokes pulse trains in the near infrared are delivered through the fiber with nearly unaltered spectral and temporal characteristics at intensities needed for endoscopy. CARS endoscopic images are recorded by collecting the epi-CARS signal generated at the sample and raster scanning the sample with respect to the fiber. This CARS endoscope prototype represents an important step towards in situ chemically selective imaging for biomedical applications.

Flow and fracture in drying nanoparticle suspensions.

Drying aqueous suspensions of monodisperse silica nanoparticles can fracture in remarkable patterns. As the material solidifies, evenly spaced cracks invade from the drying surface, with individual cracks undergoing intermittent motion. We show that the growth of cracks is limited by the advancement of the compaction front, which is governed by a balance of evaporation and flow of fluid at the drying surface. Surprisingly, the macroscopic dynamics of drying show signatures of molecular-scale fluid effects.

High-sensitivity coherent anti-Stokes Raman scattering microscopy with two tightly synchronized picosecond lasers.

We demonstrate a significant improvement in signal-to-noise ratio in coherent anti-Stokes Raman scattering (CARS) spectroscopy/microscopy, using two highly synchronized picosecond Ti:sapphire lasers. A temporal jitter between the pulse trains from the two independent commercial lasers is reduced from a few picoseconds to ~21 fs , maintained over several hours. The tight synchronization brings the fluctuation of the CARS signal down to the shot-noise limit, leading to enhanced CARS vibrational images of living cells and polymer beads.

Polarization coherent anti-Stokes Raman scattering microscopy.

We report polarization coherent anti-Stokes Raman scattering (P-CARS) microscopy that allows vibrational imaging with high sensitivity and spectral selectivity. The nonresonant background signals from both Raman scatterers and the solvent are efficiently suppressed in P-CARS microscopy. We demonstrate P-CARS imaging of unstained cells based on the contrast of the protein amide I band.