OBJECTIVE:To improve the old way of examining minimum loading capacity so as to facilitate its operation and make it meet the specific requirements of some special preparations further.METHODS:The minimum loading capacities of ulcer paste,crystal ointment and zinc oxide liniment were examined by specific gravity method,capacity substitution method and capacity addition method.RESULTS:Method for examining minimum loading capacity that failed to be examined before is available now.CONCLUSION:The improved method is reliable and easy to handle.

Peptide nucleic acid (PNA) is a DNA surrogate in which the phosphate deoxyribose backbone of DNA is replaced by repeating N-(2-aminoethyl)glycine units. PNA can hybridize to the complementary DNA and RNA with higher affinity than their oligonucleotide counterparts. This character of PNA not only makes it a new tool for the studies of molecular biology but also the potential candidate for gene-targeting drugs. The non-ionic backbone of PNA leads to stable hybrids with the nucleic acids, but at the same time, the neutral backbone results in poor cellular uptake. To address this problem, studies on modified PNA progress rapidly in recent years. We reviewed literature reports combined with our study about the delivery methods, including backbone modified PNA and PNA-ligand conjugates, and the cellular uptake of modified PNA. In addition, we summarized the problems and future prospect of the cellular delivery of modified PNA.
DNA, Complementary ; Drug Delivery Systems ; Glycine ; analogs & derivatives ; Humans ; Nucleic Acid Hybridization ; Oligonucleotides ; Peptide Nucleic Acids ; chemistry ; RNA

BACKGROUND: Strontium promotes bone formation, and reduces bone resorption. Strontium-modified titanium implant surface has been the focus of research in implant osseointegration under osteoporotic conditions. OBJECTIVE: To investigate the cell adhesion, stretch, and migration of advanced strontium-modified titanium surfaces using bone marrow mesenchymal stem cells isolated from rats. METHODS: Strontium-modified titanium surfaces were produced by sequential treatments with 5 mol/L NaOH, 100 mmol/L strontium acetate, and heated at 600 or 700 °C for 1 hour. After heat treatment, half the samples were soaked in deionized water at 80 °C for 24 hours, then washed and dried. The pure titanium served as control group, and there were five groups. The whole bone marrow adherence method was used to separate bone marrow mesenchymal stem cells from the rats. The modified titanium sheets were placed in 24-well plates and cultured in cell suspension. Cell adhesion and cell proliferation were assessed using cell counting kit-8 assay. After bone marrow mesenchymal stem cells were with the titanium sheet for 24 hours, the actin was stained to observe cell adhesion and stretch. The migration of bone marrow mesenchymal stem cells on different titanium surfaces was investigated using cell scratch test and fluorescence staining. The expression levels of collagen type І, Runx2, osteoprotegerin, RANKL and osteopontin were detected by qRT-PCR. RESULTS AND CONCLUSION: Strontium-modified titanium could promote the stretch and migration of bone marrow mesenchymal stem cells. The number of proliferative cells in the Sr700 group was significantly higher than that in the Sr600 group at 5 days (P < 0.01). On day 14, strontium-modified titanium promoted the expression of collagen type І, Runx2, and osteopontin. In summary, strontium-modified titanium can promote adhesion, spreading, migration and proliferation of rat bone marrow mesenchymal stem cells. Moreover, hydration treatment can enhance the osteogenic activity of rat bone marrow mesenchymal stem cells.

Objective The aim of this study was to investigate the differences of the cell ultrastucture of normal mouse hatched blastocysts and their dormant ones cultured in vitro after freezing-thawing, and to explore whether the dor-mant embryos have a better anti-freezing shock property than the normal hatched mouse embryos .Methods By transmis-sion electron microscopy , the ultrastructure of these two types of mouse embryos was observed and analyzed .Results By comparative analysis of their ultrastructure , the results showed that the dormant embryos before freezing are being austerity and with lower energy metabolism at a ‘ground state ’ .After freezing-thawing and culture , their cellular structure seemed to be similar to that of the normal embryos cultured in vitro before freezing.However, after freezing-thawing and culture, the number of mitochondria decreased , the nuclei were loose , and their heterochromatin also increased .Conclusions From the ultrastructural observation , compared with the normal mouse hatched embryos , the cellular state of dormant mouse em-bryos after freezing-thawing is more favorable for material storage and energy metabolism , thus, indicating that they have a better anti-freezing property than normal hatched embryos .

OBJECTIVETo investigate the presence of vasculogenic mimicry (VM) in tongue squamous cell carcinoma and explore its clinical significance.

METHODSForty-two surgical specimens of tongue squamous cell carcinoma were examined for the presence of VM using HE staining and double staining of CD34 and PAS.

RESULTSOf the 42 specimens, 18 (42.86%) showed the presence of VM. VM was not correlated with the patients' age or gender, but with lymph node metastasis and the grade of tumor differentiation. Compared with tumors without VM, the tumors with VM had a significantly higher rate of lymph node metastasis (P<0.05) and a lower grade of differentiation (P<0.05).

CONCLUSIONVM can be present in tongue squamous cell carcinoma, and the poorly differentiated tumors contain more VM, which is associated with a greater likeliness of lymph node metastasis and a poorer prognosis.

Adult ; Aged ; Aged, 80 and over ; Carcinoma, Squamous Cell ; blood supply ; Female ; Humans ; Male ; Middle Aged ; Neovascularization, Pathologic ; Tongue Neoplasms ; blood supply

Objective:To explore the microcirculation formation mechanism of contrast-enhanced ultrasonography imaging performance in rabbits with limb muscle crush injury.Methods:Seventy-two New Zealand white rabbits were randomly divided into two groups. A limb muscle crush injury model was created by airing a balloon cuff device with a force of 40 kPa. Contrast-enhanced ultrasonography parameters were detected in the first group.In vivo microcirculation parameters were detected in the second group. Fine blood vessel diameter and blood flow velocity were calculated before extrusion and 0.5 h, 2 h, 6 h, 24 h, and 3 days after decompression.Results:Totally six animals died before the end of the experiment (3 rabbits in ultrasonic imaging and microcirculation detection groups, respectively). Compared with the uninjured muscle, the reperfusion of the injured muscle showed early and high enhancement in contrast-enhanced ultrasonography images. The peak intensity and area under the curve were significantly higher than those of the control subgroup at each time point after decompression(all P<0.05), and reached the peak at 24 h after decompression. The time-intensity curve showed a trend of rapid elevation and gradual drop. In the microcirculation group, compared with the control group, fine artery and vein diameters in the experimental group were wider and the blood flow velocity was slower, especially in the fine veins(all P<0.05). At each time point after decompression, there was a statistical difference between the control subgroup and the control subgroup, and the change reached the peak at 24 h after decompression. The blood flow state showed that the arterioles were dominated by linear flow and linear grain flow at each time point after decompression, and linear grain flow, grain flow and grain pendulum flow were observed in the fine veins. Blood flow stagnation and adhesion of white blood cells and white microthrombus were also observed in the fine veins. Correlation analysis showed that the peak intensity and area under the curve were positively correlated with the inner diameter of arterioles and veins( r=0.84, 0.94; r=0.85, 0.94; all P<0.05), and negatively correlated with the flow velocity of arterioles and veins( r=-0.94, -0.96; r=-0.93, -0.96; all P<0.05). Conclusions:In vivo microcirculation detection can reflect changes in muscle microvascular diameter and blood flow velocity, which have a correlation with quantitative ultrasound imaging parameters.

Objective:To summarize the levels of individual dose to radiation workers in Shandong province from 2016 to 2020, and to analyze the trends in their change in order to provide scientific basis for radiation workers′ health management.Methods:The experimental detection and quality control were carried out in compliance with the national standards Specifications for individual monitoring of occupational external exposure (GBZ 128-2019) and the Testing criteria of personnel dosimetry performance for external exposure (GBZ 207-2016). The result of the personal dose monitoring of occupational external exposure of all radiation workers monitored by the Centers for Disease Control and Prevention in 16 cities of Shandong province were retrospectively analyzed by using SPSS 23.0 software.Results:The total number of monitored workers were 25 523 with an average annual individual effective dose of 0.28 mSv. There were statistically significant differences among radiation workers in different years ( H= 2 815.91, P<0. 001). The average annual individual effective dose showed an upward trend followed by a downward trend. The average annual effective dose of 0.55 mSv for nuclear medicine radiation workers in medical applications was the highest, with statistically significant differences among different occupational radiation workers ( H=310.37, P<0.001). The average annual effective dose of 0.37 mSv for radioactivity logging workers in industrial applications was the highest, with statistically significant differences among different occupational radiation workers ( H=448.07, P<0. 001). The average annual effective dose to radiation workers in medical applications was higher than in industrial applications ( Z = -14.93, P<0.001). Conclusions:The average annual effective dose to nuclear medicine radiation workers in medical applications and logging radiation workers in industrial applications are relatively high. There would be a push to furthe improve workplace protection measures and strengthen the management and supervision of radiological workers.

Objective To analyze the radionuclide levels in food and the committed effective dose due to food intake in residents around the Shidaowan Nuclear Power Plant (SNPP). Methods Daily food samples were collected within 30 km radius around the nuclear power plant in 2019—2022. The radioactivity levels before and after the operation of SNPP were determined. The data were combined with the dietary consumption of residents in Shandong province, China to estimate the committed effective dose. Results The radionuclides ²³⁸U, ²³²Th, ²²⁶Ra, and ⁴⁰K in food were at normal background levels, and the average radioactivity was (0.062 ± 0.004), (0.121 ± 0.007), (0.162 ± 0.010), and (92.4 ± 5.5) Bq/kg fresh weight. Trace ¹³⁷Cs and ⁹⁰Sr were detected in some food samples and the average radioactivity was (0.047 ± 0.003) and (0.193 ± 0.200) Bq/kg fresh weight. The levels of radionuclides did not increase after the operation of SNPP compared with that before operation. The estimated committed effective dose in residents due to food intake was 0.205 mSv. Conclusion The radioactivity of food in the area around SNPP shows no difference before and after operation, and the dose burden is low in local residents.

Objective To investigate the gross alpha and gross beta radioactivity levels in drinking water around Shidao Bay Nuclear Power Plant before its operation. Methods Ten sampling sites were set up within 30 km of Shidao Bay Nuclear Power Plant. From 2018 to 2021, samples were collected during the dry season and wet season each year and were tested in a laboratory according to Standard examination methods for drinking water—radiological parameters (GB/T 5750.13—2006). Results From 2018 to 2021, the gross alpha radioactivity in drinking water within 30 km of Shidao Bay Nuclear Power Plant was within the range of about 0.004-0.420 Bq/L, which does not exceed the guided gross alpha radioactivity specified in the National Standard; from 2018 to 2021, the gross beta radioactivity level was about 0.008-1.050 Bq/L. In 2018, the gross beta radioactivity at the sampling site 4.7 km from the Nuclear Power Plant exceeded the guided level specified in the National Standards for Drinking Water Quality (GB 5749—2006), but it fell within the guided level in a repeat laboratory test after deducting the effect of ⁴⁰K on the gross beta radioactivity. Conclusion After deducting the effect of ⁴⁰K on the gross beta radioactivity, the gross alpha and gross beta radioactivity levels in drinking water within 30 km of Shidao Bay Nuclear Power Plant are within the guided levels specified in the National Standards.

Chest trauma is one of the most common injuries. Venous thromboembolism (VTE) as a common complication of chest trauma seriously affects the quality of patients′ life and even leads to death. Although there are some consensus and guidelines on the prevention and treatment of VTE at home and abroad, the current literatures lack specificity considering the diagnosis, treatment and prevention of VTE in patients with chest trauma have their own characteristics, especially for those with blunt trauma. Accordingly, China Chest Injury Research Society and editorial board of Chinese Journal of Traumatology organized relevant domestic experts to jointly formulate the Chinese expert consensus on the diagnosis, treatment and prevention of chest trauma venous thromboembolism associated with chest trauma (2022 version). This consensus provides expert recommendations of different levels as academic guidance in terms of the characteristics, clinical manifestations, risk assessment, diagnosis, treatment, and prevention of chest trauma-related VTE, so as to offer a reference for clinical application.