Multi-frequency electromagnetic radiation induces anxiety in mice via inflammation in the cerebral cortex.

Modern life is filled with radiofrequency electromagnetic radiation (RF-EMR) in various frequency bands, while the health risks are not clear. In this study, mice were whole-body exposed to 0.9/1.5/2.65 GHz radiofrequency radiation at 4 W/kg for 2 h per day for 4 weeks to investigate the emotional effects. It was found that the mice showed anxiety but no severe depression. The ELISA results showed a significant decrease in amino acid neurotransmitters (GABA, DA, 5-HT), although acetylcholine (ACH) levels were not significantly altered. Furthermore, Western blot results showed that BDNF, TrkB, and CREB levels were increased in the cerebral cortex, while NF-κB levels were decreased. In addition, pro-inflammatory factors (IL-6, IL-1ß, TNF-α) were significantly elevated, and anti-inflammatory factors (IL-4, IL-10) tended to decrease. In conclusion, multi-frequency electromagnetic radiation induces an inflammatory response through the CREB-BDNF-TrkB and NF-κB pathways in the cerebral cortex and causes a decrease in excitatory neurotransmitters, which ultimately causes anxiety in mice.

Clinical and epidemiological analysis of 18 cases of Japanese spotted fever in Zigui County / 中华检验医学杂志

Objective:The epidemiological and clinical characteristics of 18 cases of Japanese spotted fever (JSF) in Zigui County were analyzed in order to improve the prevention and treatment of JSF.Methods:This is a case series analysis. The epidemiological and clinical data, laboratory tests and imaging characteristics of 18 JSF cases with median age of 60 years (54, 68) identified by The People′s Hospital of Zigui from April 2021 to August 2022 were collected and analyzed retrospectively.Results:Most (17/18) of the patients were farmers and all had a field exposure history. The patient′s onset was from April to October. Spring and autumn were the seasons with the highest incidence of JSF. The first symptoms of patients were high fever, headache, and fatigue. Of the 18 cases, 15 had a rash and 12 presented an eschar and 3 had neither rash nor eschar. In addition, 10 of 18 cases experienced edema of both lower extremities, and 3 got disturbance of consciousness. Laboratory tests found that 15 patients had abnormal white blood cells and 11 patients had decreased platelets. C-reactive protein, procalcitonin, D-dimer, lactate dehydrogenase, and alpha-hydroxybutyrate dehydrogenase were elevated in all patients; 13 patients with elevated alanine aminotransferase, 14 patients with elevated aspartate transamination. Kidney damage caused by Rickettsia japonica infection showed by abnormal proteinuria in 11 of the patients. Conclusions:The most common clinical manifestations of JSF are non-specific indications such as high fever, chills, fatigue, headache. The eschar and rash, which are the main features of Rickettsia infection, are not present in all patients, resulting delay of diagnosis or misdiagnosis. Medical workers should be more alert to rickettsial infections in patients with fever of unknown origin, especially in seasons of high incidence of spotted fever. Early diagnosis and correct antibiotic treatment shall be given according to the patient′s clinical manifestations, laboratory results and imaging test to control disease progression.

Effects of 60Co γ-rays on brain injury and polarization of microglia/macrophages in mice / 中华微生物学和免疫学杂志

Objective:To analyze the damage in hippocampal tissues of mice after whole-body irradiation with high- or low-dose ionizing radiation and to investigate the roles of microglia/macrophages polarization in the injury.Methods:C57BL/6 mice were randomly divided into three groups: sham irradiation group, low-dose group (0.05 Gy) and high-dose group (7 Gy). Low- and high-dose groups were respectively treated by whole-body irradiation with single dose of 60Co γ-rays. Hippocampal tissues of the mice were collected at 6 h, 1 d, 3 d and 7 d after irradiation. The morphology, structure and apoptosis of neurons were detected by HE staining, Nissl staining and Tunnel staining, respectively. RT-PCR and immunofluorescence assay were performed to detect the expression of M1 and M2 microglial markers at mRNA and protein levels in hippocampus tissues. The cognitive and emotional behaviors of mice were evaluated one month after the irradiation by Morris water maze, open field test, elevated plus maze and tail suspension test. Results:There were morphological and structural changes in the nerve cells in the hippocampus region of mice after irradiation, accompanied by apoptosis. Acute injuries occurred at 6 h after radiation, alleviated at 1 d and 3 d, and persisted at 7 d in a dose-dependent manner. The results of immunofluorescence staining and confocal imaging analysis showed that compared with the sham irradiation group, the high-dose group showed increased number of microglia, down-regulated expression of M1 microglial markers and up-regulated expression of M2 microglial markers in the hippocampus at 6 h and 1 d after radiation, while M2 microglial markers decreased at 3 d and 7 d after irradiation. PCR results showed that the expression of M1 and M2 microglial markers at mRNA level in the irradiation groups increased at 6 h after irradiation, but there was no statistical significance. The expression of related proinflammatory/anti-inflammatory factors was significantly up-regulated. The results of behavioral experiments showed that compared with the sham irradiation group, there was no statistical difference in cognitive or emotional behaviors at one month after irradiation.Conclusions:60Co γ-rays could damage mouse hippocampal tissues and result in the overexpression and different polarization patterns of microglia/macrophages in mice.

Racial segregation, testing sites access, and COVID-19 incidence rate in Massachusetts, USA

The U.S. has merely 4% of the world population but 25% of the worlds COVID-19 cases. Massachusetts has been in the leading position of total cases since the outbreak in the U.S. Racial residential segregation is a fundamental cause of racial disparities in health. Moreover, disparities of access to health care have a large impact on COVID-19 cases. Thus, this study estimates racial segregation and disparities in testing sites access and employs economic, demographic, and transportation variables at the city/town level in Massachusetts. Spatial regression models are applied to evaluate the relationships between COVID-19 incidence rate and related variables. This is the first study to apply spatial analysis methods across neighborhoods in the U.S. to examine the COVID-19 incidence rate. The findings are: 1) residential segregations of Hispanic and Non-Hispanic Black/African Americans have a significantly positive association with COVID-19 incidence rate, indicating the higher susceptibility of COIVD-19 infections among minority; 2) The Black has the shortest drive time to testing sites, followed by Hispanic, Asian, and Whites. The drive time to testing sites is significantly negatively associated with the COVID-19 incidence rate, implying the importance of testing location being accessed by all populations; 3) Poverty rate and road density are significant explanatory variables. Importantly, overcrowding represented by more than one person per room is a significant variable found to be positively associated with COVID-19 incidence rate, suggesting the effectiveness of social distancing for reducing infection; 4) Different from previous studies, elderly population rate is not statistically significant with incidence rate because the elderly population in Massachusetts is less distributed in the hot spot regions of COVID-19 infections. The findings in this study provide useful insights for policymakers to propose new strategies to contain the COVID-19 transmissions in Massachusetts.

Developmental relationship between mesenchymal stem/progenitor cells and hematopoietic cells dur-ing human embryogenesis / 中华微生物学和免疫学杂志

Objective To analyze the developmental relationship between mesenchymal stem/pro-genitor cells (MSPCs) and hematopoietic cells during human embryogenesis. Methods Aborted embryos at different developmental stages were used in this study after medical abortion. Embryonic blood tissues were isolated and digested into single cells. These single cells were plated in semisolid medium in favor of the dif-ferentiation of colony-forming cell with high proliferative potential ( HPP-CFC) and incubated for 10 to 14 d. Individual colonies with diameter more than 0. 5 mm were picked and replated in liquid medium. Fibroblastic adherent cells appeared in the replated colonies were cultured for cell proliferation and cytokins expressed on cell surface were identified to analyze whether they had the characteristics of MSPCs. Results This study summarized the dynamic development of HPP-CFCs and other hematopoietic progenitor cells in different tis-sues including aorta-gonad-mesonephros ( AGM) region, yolk sac and embryonic liver. From the 28-somite stage, a proportion of HPP-CFCs in AGM region could give rise to adherent fibroblastic cells in addition to hematopoietic cells. The adherent cells harbored the differentiation potential of MSPCs and could inhibit the proliferation of T cells in lymphocyte transformation test. Conclusions This study suggests some prehemato-poietic precursors in AGM region can give rise to both hematopoietic progenitors and MSPCs during human embryogenesis.

Soluble expression and bioactivity characterization of hepatic immunoregulatory protein LSECtin-CRD mutants / 中华微生物学和免疫学杂志

Objective:To construct a prokaryotic expression vector for liver and lymph node sinusoidal endothelial cell C-type lectin carbohydrate recognition domain (LSECtin-CRD) in which two amino acids were mutated to Cys and to evaluate the bioactivity of LSECtin-CRD mutants.Methods:Mutation sites were selected based on predicted 3D model of LSECtin-CRD. Site-directed mutagenesis was carried out using sequence overlapped extension PCR (SOE-PCR). The cDNA fragments of LSECtin-CRD mutants were subcloned into the prokaryotic expression vector pET28b-Tat. The expression of soluble LSECtin-CRD mutants was induced with IPTG and identified by SDS-PAGE. Ni-NTA affinity chromatography was used for purification. The bioactivities of LSECtin-CRD mutants were assessed by mannose and GlcNAc binding assays.Results:The prokaryotic expression vectors for LSECtin-CRD mutants G205C-A227C and G205C-D279C were successfully constructed as demonstrated by PCR and gene sequencing. The two mutants were efficiently expressed in soluble forms and had significant sugar-binding activities.Conclusions:Functional LSECtin-CRD mutants were successfully obtained, laying an experimental foundation for further study on the relationship between the function and structure of LSECtin-CRD.

Developmental relationship between mesenchymal stem/progenitor cells and hematopoietic cells during human embryogenesis / 中华微生物学和免疫学杂志

Objective@#To analyze the developmental relationship between mesenchymal stem/progenitor cells (MSPCs) and hematopoietic cells during human embryogenesis.@*Methods@#Aborted embryos at different developmental stages were used in this study after medical abortion. Embryonic blood tissues were isolated and digested into single cells. These single cells were plated in semisolid medium in favor of the differentiation of colony-forming cell with high proliferative potential (HPP-CFC) and incubated for 10 to 14 d. Individual colonies with diameter more than 0.5 mm were picked and replated in liquid medium. Fibroblastic adherent cells appeared in the replated colonies were cultured for cell proliferation and cytokins expressed on cell surface were identified to analyze whether they had the characteristics of MSPCs.@*Results@#This study summarized the dynamic development of HPP-CFCs and other hematopoietic progenitor cells in different tissues including aorta-gonad-mesonephros (AGM) region, yolk sac and embryonic liver. From the 28-somite stage, a proportion of HPP-CFCs in AGM region could give rise to adherent fibroblastic cells in addition to hematopoietic cells. The adherent cells harbored the differentiation potential of MSPCs and could inhibit the proliferation of T cells in lymphocyte transformation test.@*Conclusions@#This study suggests some prehematopoietic precursors in AGM region can give rise to both hematopoietic progenitors and MSPCs during human embryogenesis.

Oxidative stress effect of HPM on brain of rats / 军事医学

Objective To investigate the adverse effect of different doses of high power microwave(HPM) irradiation on oxidative stress in the brain of Wistar rats in order to contribute to establishing an animal model to evaluate protective agents which will be used for protection against microwave radiation.Methods Eighty male Wistar rats were randomly divided into 16 groups according to factor analysis.The average power density was 0,10,30 and 100 mW/cm2 and the sampling time was 6 h,1,3 and 7 d .The duration of exposure was 6 minutes for each radiation group.After exposure, the rats were sacrificed at each sampling time.Colorimetric method was used to measure the content of malondialdehyde(MDA) and protein carbonyl, the activity of GSH-px, SOD and CAT.Results The content of MDA and protein carbonyl of each radiation group was increased with the radiation dose, but decreased with the sampling time prolonged.The activity of superoxide dismutast(SOD),glutathion peroxidase(GSH-px) and catalase(CAT) in each radiation group was decreased with the radiation dose increased, and with the sampling time prolonged, but increased later.Conclusion Microwave radiation can cause oxidative stress in rats brain, as shown by the oxidative damage of lipid and protein and the decrease in the activity of antioxidant enzymes.Besides, the effect also depends on the radiation dose and sampling time.

An analysis on pathogenic bacteria distribution and drug resistance of comprehensive intensive care unit in county hospital / 中国中西医结合急救杂志

Objective To study the pathogenic bacteria species and drug resistance rate in the intensive care unit(ICU)in county hospital to guide clinical rational use of antibiotics. Methods 263 various specimens were chosen from January 2013 to December 2013 in the ICU of Zigui County People's Hospital in Hubei Province,these were applied to perform the bacterial culture and identification,and disc AGAR diffusion method was used to test the in vitro drug susceptibility and observe the specimens distribution,pathogenic distribution and the rate of drug resistance. Results In the 263 specimens,the top three isolated were 131 sputum(49.8%),49 blood(18.6%) and 38 ascites specimens(14.4%)respectively,and the pleural effusion was the least isolated with 5(1.9%). A total of 125 strains bacteria were isolated with positive detection rate of 47.5%(125/263). In the 125 strains,80(64.0%) were Gram-negative(G-)bacilli at the pioneer position,and the top four were:Klebsiella pneumonia 23(18.4%), Acinetobacter Baumanni 19(15.2%),Escherichia coli 18(14.4%)and Pseudomonas aeruginosa 12 strains(9.6%). There were 33 strains(26.4%)of Gram positive(G+)cocci including mainly Staphylococcus aureus 25 strains(20.0%);fungi strains were 12,the least(9.6%). The drug resistance rates of the top four G- bacillus were as follows:the rate of Klebsiella pneumoniae to ampicillin sodium was the highest(100%),while its rate to imipenem,meropenem and ciprofloxacin was 0;the rates of Acinetobacter baumannii to tobramycin and ceftriaxone were very high(100%, 92.3%),while to imipenem,meropennem were much lower respectively(26.3%,15.4%);the rates of Escherichia coli to ampicillin sodium and piperacillin were relatively high(88.9%,83.3%),while the rates to amikacin,imipenem, meropennem respectively were 0;the rates of Pseudomonas aeruginosa to ceftriaxone,cefotaxime sodium were very high(both 100%),while the resistant rate to levofloxacin was 0. The G+ cocci had no drug-resistance to linezolid, teicoplanin and vancomycin;the rates of Staphylococcus aureus to azithromycin,clindamycin,erythromycin and penicillin were higher than 80%,and those of Excrement enterococcus to erythromycin,gentamycin,levofloxacin were also higher than 80%. Conclusions The ICU infection of our hospital is primarily respiratory tract infection, the pathogenic bacteria are mainly G- bacilli and the antibacterial drug resistance is very serious. Therefore it is necessary to monitor the trend of bacterial resistance closely,and according to the results of bacteria identification and drug susceptibility,the antimicrobial agents are reasonably chosen to effectively reduce and control the ICU hospital infection.

Effects of military functional food NB-5 on psychological stress-induced oxidative stress / 军事医学

Objective To explore the protective effects of a new military functional food NB-5 on psychological stress-induced oxidative stress .Methods Rat whiskers were completely removed to induce the oxidative stress , and the concen-trations of MDA and protein carbonyl in various organs were detected to study the damage to membrane lipid and protein . Rats were fed with NB-5 for 4 weeks, and the oxidative stress was induced by whisker cutting .Biochemical marks men-tioned above were detected to explore the protective effects of NB-5.Results and Conclusion Lipid and protein peroxida-tion occurred in the brain , heart, liver, spleen and kidney after whisker removal due to emotional stress , while the catalase ( CAT) activity decreased significantly in these organs except the spleen .In this experiment model , NB-5 showed a good free radical scavenging activity to reduce the lipid and protein peroxidation among whisker -cutting rats fed with NB-5 in ad-vance.So NB-5 can serve as a good food for soldiers in case of emergency incidents .

Advances in protective agents against high power microwave radiation damage / 军事医学

Along with the development of science and technology , microwaves are widely used in various fields .Though they have brought much convenience to people , their potential adverse health effects are becoming a concern of governments and researchers .High power microwaves ( HPMs) are widely used in high-tech and new concept weapons , increasing the chance that troops are exposed to HPM environments .It has been clearly confirmed that microwave radiation could cause varying degrees of damage to the nervous system , immune system , cardiovascular system and reproductive system under specific conditions .Therefore , it is of important significance to reduce adverse effects of HPM radiation and improve the combat capability of troops via effective medical protection while doing well in physical protection .According to the mecha-nism and characteristics of microwave radiation damage effects , recent advances in microwave radiation protection are re-viewed in this article , hoping to facilitate research on safer and better drugs .

Microdosimetric calculation of spherical cells and ellipsoidal red blood cells in an extremely low frequency electromagnetic field / 军事医学

Objective To calculate the electric field intensity and transmembrane voltage of spherical cells and ellipsoi -dal red blood cells ( RBC) in an extremely low frequency electromagnetic field .Through this calculation , we can provide reference to the search for interaction targets and mechanics between the extremely low frequency electromagnetic field and organisms.Methods The Finite Element Method was used in the numerical computation for the spherical cell model and the ellipsoidal RBC model .Results The electric field intensity of the two types of cells on the cellular membrane was both significantly higher than the applied electric field strength , and the values of the induced field strength and transmembrane voltage varied with the direction of the electric field periodically .Conclusion The cell shape and direction of the applied electric field are not the main determinants of the cellular membrane electric field intensity and the transmembrane voltage compared with electromagnetic parameters .The distribution of the electric field intensity and transmembrane voltage are re-lated to the direction of the applied electric field.

Enamel dose calculation by electron paramagnetic resonance spectral simulation technique / 中华放射医学与防护杂志

Objective To optimize the enamel electron paramagnetic resonance (EPR) spectral processing by using the EPR spectral simulation method to improve the accuracy of enamel EPR dosimetry and reduce artificial error.Methods The multi-component superimposed EPR powder spectral simulation software was developed to simulate EPR spectrum models of the background signal(BS) and the radiation- induced signal (RS) of irradiated enamel respectively.RS was extracted from the multi-component superimposed spectrum of irradiated enamel and its amplitude was calculated.The dose-response curve was then established for calculating the doses of a group of enamel samples.The result of estimated dose was compared with that calculated by traditional method.Results BS was simulated as a powder spectrum of gaussian line shape with the following spectrum parameters:g =2.00 35 and Hpp =0.65 - 1.1 mT,RS signal was also simulated as a powder spectrum but with axi-symmetric spectrum characteristics.The spectrum parameters of RS were:g(1) =2.0018,g (11) =1.996 5,Hpp =0.335 - 0.4 mT.The amplitude of RS had a linear response to radiation dose with the regression equation as y =240.74x + 76 724 ( R2 =0.9947 ).The expectation of relative error of dose estimation was 0.13.Conclusions EPR simulation method has improved somehow the accuracy and reliability of enamel EPR dose estimation.

Application of ESR imaging technique in studying of skin-penetration properties of nitroxide free radical / 生物医学工程学杂志

A set of L-band electron spin resonance imaging (ESRI) equipment suitable for biological species was developed and an ESRI experiment model for viable skin samples was established. The mechanic process of nitroxide free radical TEMPO (2,2, 6, 6-tetramethyl-1-piperidinyloxy) penetrating through skin sample and the spin density distribution of TEMPO after it interacted with skin sample were detected by the developed ESRI method. Skin samples were extracted from mice back. The experimental samples were prepared by cutting the skin pieces into square shape of 2 x 2 cm2 and then the samples were divided into three groups by treating them with three different methods: Method A, simple treatment by simply cutting the hair; method B, 8% Na2S depilation treatment for 10 min; method C, 8% Na2S depilation and then 5% pancreatic digestion treatment for 2 hours. The liposoluble solvent DMSO (dimethyl sulfoxide) and distilled water were used as two kinds of solvent for the TEMPO liquor. The results indicated that the skin-penetration properties of TEMPO were significantly different among samples treated with different methods and the surface cornifin of skin offered remarkable resistance to TEMPO. The TEMPO liquor of water could hardly penetrate through skins, whereas about 20%-30% of the original TEMPO compounds that solved in liposoluble solvent DMSO could penetrate through the skin sample treated with method C after 16 hours of interaction. Furthermore, the penetration rate of TEMPO through the skin tissue was a strong time dependent process. The preliminary application results suggested that ESRI technique could provide an effective and applicable method for dynamically researching skin-penetration properties of some special kinds of materials such as paramagnetic compounds.

Plate form three-dimensional gradient coils for L-band ESR imaging experiment.

A set of plate form three-dimensional magnetic gradient coils was developed and used in electron spin resonance imaging (ESRI) experiment. The coils were processed with whole copper plates instead of wound with copper wires, which made its structure so compact that it was much thinner and smaller comparing to those traditionally used in ESRI. The coil set had a pie-like appearance of which the total thickness was only 14 mm and the outer diameter was 250 mm. The efficiency of the coils could be greater than 10 mT/m/A when distance between the two side-pieces was 63 mm. A maximum gradient strength of more than 200 mT/m could be obtained with driving current of about 20 A in each dimension coil. The spatial linearity was better than 5% in all three dimensions within the available spatial linearity area of larger than a sphere of 40 mm in diameter. The stability of the gradients strength could reach the level of 10(-5). An imaging resolution of better than 1 mm could be achieved with the coil set. Some preliminary practical imaging results show that the developed gradient coil set is suitable for L-band ESRI experiment of biological samples or even in vivo small animals.

Novel high pressure extraction technology.

This note describes a novel application of the food processing technology, known as high pressure processing (HPP), to the extraction of essential components of herbs. Herbal extracts may be used as drugs, as well as ingredients in food and cosmetics. We have run some pilot studies in our laboratories to demonstrate the applicability of high pressure extraction.

The effects of electromagnetic pulse on fluidity and lipid peroxidation of mitochondrial membrane / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the effects of intense electromagnetic pulse(EMP) on the biological effects of mitochondrial membrane.</p><p><b>METHOD</b>Rat liver mitochondrial suspension was exposed to EMP at 60 kV/m level. The changes of membrane lipid fluidity and membrane protein mobility were detected by ESR and spin label technique. Malondialdehyde(MDA) was detected by spectrophotometer.</p><p><b>RESULTS</b>The mobility of membrane protein decreased significantly(P < 0.05). Correlation time (tau c) of control group was (0.501 +/- 0.077) x 10(-9)s, and tau c of EMP group was (0.594 +/- 0.049) x 10(-9)s, indicating that the mobility of protein was restricted. The fluidity of mitochondrial membrane increased significantly(P < 0.05) at the same time. Order parameter(S) of mitochondrial membrane lipid in control group was 0.63 +/- 0.01, while S of EMP group was 0.61 +/- 0.01(P < 0.05). MDA decreased significantly.</p><p><b>CONCLUSION</b>The mobility and lipid peroxidation of mitochondrial membrane may be disturbed after EMP exposure.</p>