Isotope shifts in electron affinities and in binding energies of Pb and hyperfine structure of 207Pb.

The isotope shifts in electron affinities of Pb were measured by Walter et al. [Phys. Rev. A 106, L010801 (2022)] to be -0.002(4) meV for 207-208Pb and -0.003(4) meV for 206-208Pb by scanning the threshold of the photodetachment channel Pb-(S3/2◦4) - Pb (3P0), while Chen and Ning reported 0.015(25) and -0.050(22) meV for the isotope shifts on the binding energies measured relative to 3P2 using the SEVI method [J. Chem. Phys. 145, 084303 (2016)]. Here we revisited these isotope shifts by using our second-generation SEVI spectrometer and obtained -0.001(15) meV for 207-208Pb and -0.001(14) meV for 206-208Pb, respectively. In order to aid the experiment by theory, we performed the first ab initio theoretical calculations of isotope shifts in electron affinities and binding energies of Pb, as well as the hyperfine structure of 207Pb-, by using the MCDHF and RCI methods. The isotope shifts in electron affinities of 207-208Pb and 206-208Pb are -0.0023(8) and -0.0037(13) meV for the 3P0 channel, respectively, in good agreement with Walter et al.'s measurements. The isotope shifts in binding energies relative to 3P1,2, -0.0015(8) and -0.0026(13) meV for 207-208Pb and 206-208Pb, respectively, are compatible with the present measurements. The hyperfine constant for the ground state of 207Pb- obtained by the present calculations, A(S3/2◦4)=-1118 MHz, differs by a factor of 3 from the previous estimation by Bresteau et al. [J. Phys. B: At., Mol. Opt. Phys. 52, 065001 (2019)]. The reliability is supported by the good agreement between the theoretical and experimental hyperfine parameters of 209Bi.

[Investigation on population dynamics and Echinococcus infections in small rodents around human settlement in Yushu City, Qinghai Province].

OBJECTIVE: To investigate the population dynamics and Echinococcus infections in small rodents around human settlement in Yushu City, Qinghai Province. METHODS: Rodents were captured using the mouse trap method in pastures from Batang Township and Longbao Township of Yushu City, Qinghai Province on May, August and October, 2018. The body weight and snout-vent length of all captured rodents were measured, and the species was identified according to the rodent morphology. Genomic DNA was extracted from rodent liver specimens and lesion specimens, and the mitochondrial cox1 gene of Echinococcus was amplified using PCR assay for identification of parasite species. In addition, the tissue specimens positive for PCR assay were sampled for pathological examinations. The prevalence of Echinococcus infections was estimated in rodents, and a phylogenetic tree was created based on Echinococcus cox1 gene sequences. RESULTS: A total of 285 small rodents were captured, including 143 Ochotona curzoniae (50.2%), 141 Lasiopodomys fuscus (49.5%), and 1 Neodon irene (0.3%), and there was a remarkable variation in habitat selection among these three rodent species. The number of L. fuscus correlated positively with vegetation coverage (r = 0.350, P = 0.264), with the greatest number seen in August, and the number of O. curzoniae negatively with vegetation coverage (r = -0.371, P = 0.235), with the highest number seen in August and the lowest number in May. The female/male ratios of O. curzoniae and voles were 1:0.96 and 0.82:1, respectively. The body weight (r = 0.519, P < 0.01) and snout-vent length (r = 0.578, P < 0.01) of O. curzoniae showed a tendency towards a rise with month, while the body weight (r = -0.401, P < 0.01) and snout-vent length (r = -0.570, P < 0.01) of voles presented a tendency towards a reduction with month. No Echinococcus infection was detected in voles, while 2.1% prevalence of E. shiquicus infection was seen in O. curzoniae. Phylogenetic analysis revealed consistent sequences of cox1 gene from E. shiquicus in Yushu City of Qinghai Province and Shiqu County, Ganzi Tibetan Autonomous Prefecture of Sichuan Province. CONCLUSIONS: The small rodents around the human settlement in Yushu City of Qinghai Province mainly include O. curzoniae and L. fuscus, with the greatest numbers seen in May and August, respectively. Following the concerted efforts for echinococcosis control, the prevalence of Echinococcus infections is low in small rodents around the human settlement in Yushu City; however, there is still a risk of echinococcosis transmission.

Sequence and Phylogenetic Analyses of the Nsp2 and ORF5 Genes of Porcine Reproductive and Respiratory Syndrome Virus in Boars from South China in 2015.

Porcine reproductive and respiratory syndrome virus (PRRSV) is highly genetically diverse; however, little is known about the molecular epidemiology of PRRSV in the boar farms of South China. In this study, 367 samples were collected from boar farms in South China in 2015. The Nsp2 hypervariable region and ORF5 gene were PCR amplified from 66 PRRSV-positive samples, followed by sequencing and analysis. The percentage of PRRSV antigen-positive samples was 17.98%; 8.72% were positive for highly pathogenic PRRSV (HP-PRRSV), and 9.26% were positive for low pathogenic PRRSV (LP-PRRSV). Sequence alignment and phylogenetic tree analyses revealed three novel patterns of deletion in the hypervariable region of Nsp2, which had not been identified previously. Furthermore, numerous amino acid substitutions were identified in the putative signal peptide and extravirion regions of GP5. These results demonstrate for the first time that the existence of multiple different strains on the same boar farm, and extensive genetic mutation and high infection rate of PRRSV in boars from South China. Our research contributes to the understanding of the epidemiology and genetic characteristics of PRRSV on boar farms.

Positive evolution of the glycoprotein (GP) gene is related to transmission of the Ebola virus.

Ebola hemorrhagic fever is a fatal disease caused by the negative-strand RNA of the Ebola virus. A high-intensity outbreak of this fever was reported in West Africa last year; however, there is currently no definitive treatment strategy available for this disease. In this study, we analyzed the molecular evolutionary history and attempted to determine the positive selection sites in the Ebola genes using multiple-genomic sequences of the various Ebola virus subtypes, in order to gain greater clarity into the evolution of the virus and its various subtypes. Only the glycoprotein (GP) gene was positively selected among the 8 Ebola genes, with the other genes remaining in the purification stage. The positive selection sites in the GP gene were identified by a random-site model; these sites were found to be located in the mucin-like region, which is associated with transmembrane protein binding. Additionally, different branches of the phylogenetic tree displayed different positive sites, which in turn was responsible for differences in the cell adhesion ability of the virus. In conclusion, the pattern of positive sites in the GP gene is associated with the epidemiology and prevalence of Ebola in different areas.

[Efficacy and mechanism of local delivery of rapamycin and rapamycin-loaded poly(lactic-co-glycolic) acid nanoparticles on coronary restenosis of injury-stenosis model of minipigs].

OBJECTIVE: To determine whether intramural administration of rapamycin (RPM)-loaded polylactic-polyglycolic acid (PLGA) nanoparticles (NPs) can reduce intimal thickening and affect the mRNA expressions of matrix metalloproteinase (MMP)-2, tissue inhibitor of metalloproteinase (TIMP)-2 and p27(kipl) in a coronary injury-stenosis model of minipigs. METHODS: Twenty eight minipigs were randomly separated into four groups: saline group (n=7), blank PLGA NPs group (5.0 mg/ml)(n=7), RPM group (1.0 mg/ml)(n=7), and RPM-PLGA NPs(5.0 mg/ml)group (n=7), respectively. Different treatments were intracoronary locally delivered via a Dispatch™ catheter for 10 minutes. Serial angiography was performed pre-and post-modeling 30 days and the percent stenosis degree was assessed. Hematoxylin-Eosin (HE) staining, Weigert's resorcin fuchsin staining and picric acid-sirius red staining were used for morphometric analysis. Immunohistochemistry was performed to assess the levels of proliferating cell nuclear antigen (PCNA), MMP-2, and TIMP-2 at early and late time points, respectively. The expression of p27(kip1) mRNA was detected by in situ hybridization staining. RESULTS: Data from 21 minipigs had been collected at the end of the experiment with 6, 4, 5, and 6 from the former mentioned 4 groups, respectively. For the instant injury index, there was no significant difference among the four groups. The percent stenosis degree of RPM-PLGA NPs group was significantly lower than that of the other three groups respectively (all P< 0.05). The neointima area, net external elastic lamina area to external elastic laminal area ratio, and proliferative index of RPM-PLGA NPs group were significantly less than those of the other three groups, with all the P values less than 0.05. The mean value of integral optical density of p27(kip1)mRNA expression of RPM-PLGA group was 0.35 ± 0.06, higher than that of blank PLGA NPs group (0.12 ± 0.05, P< 0.01), saline group (0.16 ± 0.03, P< 0.05), and RPM group (0.15 ± 0.03, P< 0.05), respectively. The MMP-2/TIMP-2 ratio and the positive expression index of PCNA in RPM-PLGA group were lower than that of the other groups (P< 0.05). CONCLUSIONS: Locally delivered rapamycin-loaded PLGA NPs significantly reduces MMP-2/TIMP-2 ratio and PCNA expression, increases p27(kip1) mRNA expression and significantly relieves percent stenosis degree and shows excellent acute procedural results in the minipig interventional coronary artery oversized balloon injury model. The results from minipig model further support that this approach could be a potential clinical procedure for vascular proliferative disease.

Serum cytokine modulation after Staphylococcus hyicus infection in BALB/c mice.

Staphylococcal infection is a severe bacterial infection. Finding satisfactory predictable biological markers is essential for the treatment of this condition. In this study, we applied a 32-marker sandwich ELISA-based antibody array to evaluate cytokine changes in Staphylococcus hyicus-inoculated BALB/c mice at 24 and 48 h post infection. Among the cytokines detected, the expression levels of granulocyte colony stimulating factor (G-CSF), interleukin 6 (IL-6), macrophage inflammatory protein 2, and keratinocyte chemoattractant (KC) were increased to levels more than twice higher than those in the control group 24 h after infection, while the expression of interleukin 12p40p70 (IL-12p40p70) was decreased to less than half the level measured in the controls. The expression of G-CSF, IL-6, monocyte chemoattractant protei-5, chemokine ligand 11, and KC was upregulated 48 h post infection, whereas IL-12p40p70 expression was still significantly lower (P < 0.05). Among the detected cytokines, the expression levels of G-CSF, IL-6, and KC were constantly upregulated, while IL-12p40p70 was downregulated. This result was then validated by an ELISA assay analysis, which confirmed that G-CSF, IL-6, KC, and IL- 12p40p70 expression levels were specifically modulated after an S. hyicus bacterial infection, while granulocyte monocyte colony stimulation factor, IL-12, and IFNγ levels were significantly increased after a viral infection. Our study indicated the potential of cytokines G-CSF, IL-6, KC, and IL- 12p40p70 as markers for detecting S. hyicus infection. The results of this study may provide useful data for the appropriate use of medication following S. hyicus infection.

MCP-1 gene polymorphisms in North Chinese patients with pulmonary tuberculosis.

Pulmonary tuberculosis (PTB) remains one of the most important infectious diseases worldwide. Several studies have suggested that genetic factors may affect the susceptibility to PTB, but the specific genes involved have not been fully characterized. The gene for monocyte chemoattractant protein 1 (MCP-1) has been linked to an increased risk of tuberculosis in some Mexican and Korean populations. To explore the role of the MCP-1 gene in the susceptibility to PTB in a North Chinese population, we evaluated the association between MCP-1 -2518A/G gene polymorphisms and the risk for tuberculosis. Polymerase chain reaction amplification of genomic DNA followed by restriction fragment length polymorphism analysis was used. There was a significant increase in the frequency of the GG genotype of MCP-1 -2518 in 136 patients with PTB compared to that in 152 healthy controls (P = 0.008, X(2) = 7.133, odds ratio = 1.96). Similarly, the frequencies of the A/G alleles in the 2 groups differed; the frequency of allele G was higher in patients with PTB (P = 0.011, X(2) = 6.428, odds ratio = 1.536). In conclusion, the -2518A/G polymorphism in the MCP-1 gene was found to be associated with an increased susceptibility to PTB in a North Chinese population.

Research progress in the radioprotective effect of superoxide dismutase.

Irradiation from diverse sources is ubiquitous and closely associated with human activity. Radiation therapy (RT), an important component of the multiple radiation origins, contributes significantly to oncotherapy by killing tumor cells. On the other hand, RT can also cause some undesired normal tissue injuries that afflict numerous cancer patients. Although many promising radioprotective agents are emerging, few of them have entered the market successfully due to various limitations. At present, the most accepted hypothesis for the radiation-caused injury involves reactive oxygen species (ROS) generation. Superoxide dismutase (SOD), the unique enzyme responsible for the dismutation of superoxide radicals, is expected to occupy an indispensable position in the treatment of ROS-mediated tissue injuries originating from exposure to radiation. This review focuses on the mechanism of radioprotection by SOD at the tissue or organ level, cellular level, and molecular level, respectively, in order to provide references for further investigation of radiation injury and development of new radioprotectors.

Association of HLA-DRB alleles and pulmonary tuberculosis in North Chinese patients.

Human leukocyte antigen (HLA) plays a central role in the regulation of the immune response. HLA class II molecules are essential for T cell-mediated adaptive immunity and present peptide antigens to CD4(+) T cells. Because of its important role in the immune response and its high degree of polymorphism, the HLA system is associated with many diseases. We examined the polymorphisms of HLA-DRB alleles and the sequences of the HLA-DRB promoter region in 97 unrelated patients with pulmonary tuberculosis and in 62 unrelated normal controls of the Han nationality from North China, using PCR with sequence-specific primers and PCR direct sequencing. We found that the frequency of HLA-DRB1*15 was significantly higher in the pulmonary tuberculosis group than in the healthy control group. The P value was 0.001, and the odds ratio was 3.793. The pulmonary tuberculosis group had the same HLA-DRB1 promoter region sequences as the control group. We concluded that the HLA-DRB1*15 allele is associated with pulmonary tuberculosis in the Han nationality from North China. The HLA-DRB1 promoter region sequences had no association with the development of pulmonary tuberculosis.

Genotyping and drug resistance patterns of Mycobacterium tuberculosis strains in five provinces of China.

OBJECTIVE: To evaluate the distribution of the Mycobacterium tuberculosis Beijing genotype and the association of the genotype with drug-resistant M. tuberculosis strains in five provinces in China. DESIGN: M. tuberculosis strains (n = 158) isolated from five provinces of China were subjected to insertion sequence 6110 restriction fragment length polymorphism (RFLP), spoligotyping and mycobacterial interspersed repetitive units (MIRU) analyses. The prevalence of the Beijing genotype strains in each province was determined and compared. The proportion method was used to test the drug susceptibility of all strains. RESULT: Of the 158 strains, 123 (77.8%) were identified as the Beijing genotype by RFLP and spoligotyping. Nearly all the strains (n = 152, 96.2%) were grouped into 14 shared spoligotypes. Six other spoligotypes were unique to China. The prevalence of the Beijing genotype was significantly higher in the interior than in coastal areas (P < 0.001, OR 5.4, 95%CI 2.3-12.7). Resistance to rifampicin (RMP) was associated with the Beijing strain (P = 0.05, OR 3.7, 95%CI 1.2-11.1). CONCLUSION: The M. tuberculosis Beijing genotype varies in prevalence in different regions of China and is solely associated with RMP resistance.

Analysis of HLA-A, HLA-B and HLA-DRB1 alleles in Chinese patients with lung cancer.

The primary function of the human leukocyte antigen (HLA) system is to regulate the immune response. Because of its important role in the immune response and its high degree of polymorphism, the HLA system is associated with many diseases. We examined the polymorphisms of HLA-A, B and DRB1 alleles in 100 unrelated patients with lung carcinoma and in 438 unrelated normal controls of Han nationality from North China, using sequence-based typing and PCR with sequence-specific primers. We found that the frequencies of HLA-A*0201, A*2601, B*1518, B*3802, DRB1*0401, DRB1*0402, and DRB1*1201 were higher in the lung carcinoma group than in the normal control group. The P values were 0.035, 0.040, 0.001, 0.017, 0.014, 0.004, and 0.019, respectively, and the odds ratio values were 1.052, 3.513, 4.047, 3.054, 4.237, 19.397, and 2.128, respectively. The frequency of HLA-DRB1*1302 was lower in the lung carcinoma group than in the normal control group (P = 0.046, odds ratio = 0.168). We concluded that patients with lung cancer and healthy controls of Han nationality from North China differ in the frequencies of various HLA alleles.

Relationship between genetic polymorphism of MCP-1 and non-small-cell lung cancer in the Han nationality of North China.

Monocyte chemoattractant protein 1 (MCP-1) is an important chemokine that has a dose-dependent anti-tumoral effect. Polymorphism in the MCP-1 distal regulatory region (-2518A/G) can affect the level of MCP-1 expression. We examined the polymorphisms of 112 unrelated patients with non-small-cell lung cancer (NSCLC) and 82 unrelated healthy controls of Han nationality in North China using PCR-RFLP. We found that the distributions of AA, AG and GG genotypes of MCP-1-2518 were significantly different in NSCLC patients compared to controls (chi(2) = 10.106, P = 0.006). There was a significant increase in the frequency of the AA genotype (odds ratio (OR) = 3.138, chi(2) = 8.905, P = 0.003) and a significant decrease in the frequency of the GG genotype (OR = 0.516, chi(2) = 4.613, P = 0.032) in the NSCLC patients, compared to controls. The frequencies of AA, AG and GG genotypes did not differ in the NSCLC patients according to the number of pack-years smoked. Based on these results, we suggest that the MCP-1 -2518A/G polymorphism is associated with genetic susceptibility to NSCLC.

The polymorphism of HLA antigens in the Chinese.

Remarkable differences were observed in antigen frequencies (AF), gene frequencies (GF) and haplotype frequencies (HF) when 2441 healthy Chinese individuals representing nine different ethnic groups and living in 14 different geographic locations were examined for the genetic distribution of the various HLA Class I and II markers. A sizable number of individuals of each ethnic group within each of the three major categories of the Chinese population, namely, Hans, Mongols, and Southern minorities, have been studied here, providing useful population statistics for applications such as determination of probabilities of paternity, comparisons for HLA and disease associations, and anthropologic studies.