Relationship between the impacted mandibular third molar and adjacent second molar' external root resorption by conebean computed tomography analysi / Relación entre la reabsorción de la raíz externa del tercer molar mandibular impactado y el segundo molar adyacente mediante análisis de tomografía computarizada de cono

Background: The relationship between the impacted mandibular third molar (IMTM) and the external root re-sorption (ERR) of the mandibular second molar (MSM) was analysed with cone-beam computed tomography(CBCT). The risk factors affecting the ERR of the MSM were examined to provide a reference.Material and Methods: A total of 327 patients (total: 578 teeth) admitted to the Affiliated Hospital of YanbianUniversity for IMTM extraction from January 2017 to December 2019 was chosen and divided according togender and age. The correlation between the IMTM and ERR of MSM was analysed, including inclination angle,impaction direction and depth. The relationship of mandibular ascending ramus classification with ERR of MSMwas also analysed. In addition, the correlation between the MTM impaction type and the severity of ERR wasanalysed.Results: The incidence of ERR of MSM in male patients was higher than in females (27.9% vs.17.6%, p = 0.018).The occurrence and the site of ERR showed statistical differences in the inclination angle [(≤20°, 3.6%) vs. (21°-40°, 27.1%) vs. (41°-60°, 27.6%) vs. (61°-80°, 25.6%) vs. (>80°, 31.7%), p <0.001], impaction direction [(Vertical,1.1%) vs. (Mesial, 32.7%) vs. (Horizontal, 25.3%), p <0.001] and depth of MTM [(Low position, 38.6%) vs. (Medi-an position, 32.0%) vs. (High position, 13.7%), p <0.001]. Also, there was a significant difference in the mandib-ular ascending ramus type [(Class I, 17.4%) vs. (Class II, 32.3%) vs. (Class III, 44.9%), p <0.001]. In addition, theseverity of ERR showed statistical differences in the mesial (40.9%, p<0.05), lower impaction (54.5%, p<0.05)depth of MTM and type III of mandibular ascending ramus (63.6%, p<0.05).Conclusions: The inclination angle, impaction direction, and depth of MTM were the influencing factors for theoccurrence and site of ERR.(AU)

Cone-Beam Computed Tomography Analysis on the Relationship between the Mandibular Third Molar and the Position of the Mandibular Canal in Koreans from the Yanbian Area and the Han People.

Objective: To analyze differences in the positional relationships between the mandibular third molar (MTM) and the mandibular canal in Korean and Han patients using cone-beam computed tomography (CBCT) and to provide a basis for preoperative risk assessments. Materials and Methods: The CBCT imaging data of 260 Korean and Han patients were collected. The patients' genders, ages, impaction types and depths, relative positions between the MTMs and the mandibular nerve canals, and the shortest distances and shapes at the root tips and cortical bones were all recorded and analyzed. All data were compared using the nonparametric test, ordered logistic regression analysis, a chi-square test, and Fisher's exact test. Results: The relationship between the mandibular canal and the relative position of the MTM differed between Korean and Han patients, mainly in the different types of impactions, and the difference was statistically significant (P < 0.05). The shortest distance between the mesioangular and horizontally impacted mandibular canals and the buccal side of the MTM in Korean patients was less than in Han patients, and the difference was statistically significant (P < 0.05). For horizontal impactions, the probability of cortical bone interruption was 1.980 times greater in Korean patients than in Han patients, and the difference was statistically significant (P < 0.05). The significance threshold was set at 0.05. Conclusion: There are some differences in the positional relationship between the mandibular canal in the MTM region and the rate of cortical bone disruption between Koreans from the Yanbian area and the Hans. This should gain clinical attention.

Diterpenoids from Sauropus spatulifolius Leaves with Antimicrobial Activities.

As a plant used in both food and medicine, Sauropus spatulifolius is consumed widely as a natural herbal tea, food source, and Chinese medicine. Inspired by its extensive applications, we conducted a systematic phytochemical study of the leaves of S. spatulifolius. Thirteen new diterpenoids, sauspatulifols A-M (1-13), including four ent-cleistanthane-type diterpenoids (1-4), eight 15,16-di-nor-ent-cleistanthane-type diterpenoids (5-12), and one 17-nor-ent-pimarane-type diterpenoid (13) as well as one known diterpenoid, cleistanthol (14), were isolated. All of these diterpenoids feature a 2α,3α-dihydroxy unit within the A ring, and their structures were elucidated by spectroscopic data analysis, electronic circular dichroism calculations, and single-crystal X-ray diffraction analysis. Compound 14 displayed moderate inhibitory activity against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, and Shigella flexneri with the same minimum inhibitory concentration value of 12 µg/mL as well as activity against vesicular stomatitis virus and influenza A virus.

Human MxB Inhibits the Replication of Hepatitis C Virus.

Type I interferon (IFN) inhibits viruses by inducing the expression of antiviral proteins. The IFN-induced myxovirus resistance B (MxB) protein has been reported to inhibit a limited number of viruses, including HIV-1 and herpesviruses, but its antiviral coverage remains to be explored further. Here we show that MxB interferes with RNA replication of hepatitis C virus (HCV) and significantly inhibits viral replication in a cyclophilin A (CypA)-dependent manner. Our data further show that MxB interacts with the HCV protein NS5A, thereby impairing NS5A interaction with CypA and NS5A localization to the endoplasmic reticulum, two events essential for HCV RNA replication. Interestingly, we found that MxB significantly inhibits two additional CypA-dependent viruses of the Flaviviridae family, namely, Japanese encephalitis virus and dengue virus, suggesting a potential link between virus dependence on CypA and virus susceptibility to MxB inhibition. Collectively, these data have identified MxB as a key factor behind IFN-mediated suppression of HCV infection, and they suggest that other CypA-dependent viruses may also be subjected to MxB restriction.IMPORTANCE Viruses of the Flaviviridae family cause major illness and death around the world and thus pose a great threat to human health. Here we show that IFN-inducible MxB restricts several members of the Flaviviridae, including HCV, Japanese encephalitis virus, and dengue virus. This finding not only suggests an active role of MxB in combating these major pathogenic human viruses but also significantly expands the antiviral spectrum of MxB. Our study further strengthens the link between virus dependence on CypA and susceptibility to MxB restriction and also suggests that MxB may employ a common mechanism to inhibit different viruses. Elucidating the antiviral functions of MxB advances our understanding of IFN-mediated host antiviral defense and may open new avenues to the development of novel antiviral therapeutics.

Gene expression rate comparison for multiple high-throughput datasets.

Microarray provides genome-wide transcript profiles, whereas RNA-seq is an alternative approach applied for transcript discovery and genome annotation. Both high-throughput techniques show quantitative measurement of gene expression. To explore differential gene expression rates and understand biological functions, the authors designed a system which utilises annotations from Kyoto Encyclopedia of Genes and Genomes (KEGG) biological pathways and Gene Ontology (GO) associations for integrating multiple RNA-seq or microarray datasets. The developed system is initiated by either estimating gene expression levels from mapping next generation sequencing short reads onto reference genomes or performing intensity analysis from microarray raw images. Normalisation procedures on expression levels are evaluated and compared through different approaches including Reads Per Kilobase per Million mapped reads (RPKM) and housekeeping gene selection. Such gene expression levels are shown in different colour shades and graphically displayed in designed temporal pathways. To enhance importance of functional relationships of clustered genes, representative GO terms associated with differentially expressed gene cluster are visually illustrated in a tag cloud representation.

[Establishment of drug screening assay and pharmacodynamic evaluation method targeting influenza RNA polymerase].

Influenza virus RNA-dependent RNA polymerase (RdRP) is essential for replication and expression of influenza virus genome. Viral genomic sequences encoding RdRP are highly conservative, thus making it a potential anti-influenza drug target. A cell-based influenza RdRP inhibitor screening assay was established by a luciferase reporter system to analyze the activity of RdRP. Specificity study and statistic analysis showed that the screening assay is sensitive and reproducible.

[Establishment and drug susceptibility test of isoniazid resistant Mycobacterium smegmatis].

With the emergence of drug resistant tuberculosis, it is very urgent to find novel anti-tuberculosis drugs, especially novel anti-drug-resistant tuberculosis drugs. Because of the slow growth and the need to work in a biosafty environment of Mycobacterium tuberculosis, the development of evaluation of drug effect is severely impeded. In order to solve these issues, non-pathogenic fast-growing Mycobacterium smegmatis is introduced as test organism. The inhA is one of a target of isoniazid (INH) overexpression or mutation of this gene in Mycobacterium tuberculosis conferring resistant to INH. A recombinant plasmid bearing inhA was constructed and electroporated into Mycobacterium smegmatis, using shuttle expression vector pMV261. Transformants were induced to express a protein of inhA, identified by SDS-PAGE. Results show that Mycobacterium smegmatis containing inhA plasmids exhibited 100-fold or greater increased resistance to INH, but it conferred no increased resistance to others first-line anti-tuberculosis drugs. Resazurin microtiter assay plate testing of Mycobacterium smegmatis susceptibility to drugs is a rapid, simple, and inexpensive method and could decrease color background of drugs by detecting fluorescence. It will be benefit for high-throughout screening of drugs of anti-isoniazid-resistant Mycobacteria.

[Establishment and application of a high-throughput screening assay for premature activation of HIV-1 precursors].

Strict regulation of HIV-1 PR function is critical for efficient production of mature viral particles. During viral protein expression and viral assembly, HIV-1 PR located within Gag-Pol precursor must be inactive to prevent premature cytoplasmic processing of the viral Gag and Gag-Pol precursors. Premature activation of HIV-1 precursors leads to major defects in viral assembly and production of viral particles. A cell-level premature activation of HIV-1 precursors assay using bioluminescence resonance energy transfer (BRET) was established. Three thousand compounds were screened to evaluate this assay. The results showed that the assay is sensitive, specific and stable (Z' factor is 0.905).

[Establishment and application of a screening anti-HIV-1 drug model targeted nuclear trafficking of virus RNA].

The HIV-1 Rev protein facilitates nuclear export of unspliced and singly spliced viral transcripts containing RRE RNA through the CRM1 export pathway. Inhibition of Rev-mediated RNA nuclear export can arrest HIV-1 transcriptional process, which clearly, reveals a target for anti-HIV drug development. In this work, a cell-based assay has been established for screening anti-HIV compounds targeting the Rev-mediated RNA nuclear export. This assay utilized a codon-optimized green fluorescent protein (GFP) as reporter gene, which expression is in a Rev-dependent manner. Any compound that inhibits the Rev-mediated RNA nuclear export is identified by reducing emission of GFP. The Z' score of this model is 0.8220. Three thousands compounds were screened and the positive rate was 9.3% with a cutoff at 50% inhibition. IMB7C7, one of the positive compounds, efficiently inhibits viral production from HIV-1 infected cells.

[Construction and expression of eukaryotic expression plasmid containing rat TCR Vbeta8.2 gene].

AIM: To construct the recombinant eukaryotic expression vector pTARGET-TCR Vbeta8.2 and detect its their expression. METHODS: Gene encoding TCR Vbeta8.2 was amplified by RT-PCR from spleen cells of Lewis rats, and then cloned into eukaryotic expression vector pTARGET. Recombinant clones were identified by blue/white screening on indicator plates after transformed into E.coli strain JM109, and then by bacteria colonies PCR and DNA sequencing. Recombinant plasmid was injected into BALB/c mice intramuscularly. Then the injected skeletal muscle was isolated, and expression of TCR Vbeta8.2 gene was detected by RT-PCR and immunohistochemistry. Immunocytochemical staining was used to detect the expression of pTARGET-TCR Vbeta8.2 gene after the recombinant plasmid was transfected into COS-7 cells by lipofectamine. RESULTS: DNA sequencing demonstrated that TCR Vbeta8.2 gene was successfully inserted into pTARGET. RT-PCR demonstrated that TCR Vbeta;8.2 gene was successfully expressed in the injected muscle. Immunohistochemistry staining showed the expression of recombinant plasmid in the transfected COS-7 cells. CONCLUSION: The eukaryotic expression vector pTARGET-TCR Vbeta8.2 was successfully constructed and expressed in vivo and vitro, which would lay foundation for further studies on the protective effects of TCR Vbeta DNA vaccine on CIA.

[Analysis of TCR Vbeta clonotypes of T lymphocytes infiltrating in the joints of rats with collagen-induced arthritis].

AIM: To investigate the TCR Vbeta clonetypes of T lymphocytes infiltrating in the synovium of rats with collagen induced arthritis (CIA). METHODS: Type II collagen was used to induce arthritis in Lewis rats. CD4(+) and CD8(+) T lymphocytes in peripheral blood of the rats were analyzed by flow cytometry (FCM). Total RNA was extracted from rat joint tissues and TCR Vbeta clonotypes were identified by RT-PCR and single-strand conformation polymorphism (SSCP). Splenic lymphocytes from CIA rats were transferred into normal Lewis rats. TCR Vbeta clonotypes of T lymphocytes infiltrating in the joints of the recipient rats were also analyzed by RT-PCR/SSCP. RESULTS: FCM analysis of the T lymphocytes indicated that CD8(+) T lymphocytes decreased in CIA rats and the CD4(+)/CD8(+) T lymphocytes ratio was >2, which suggested that there was a disproportion of the T lymphocyte subsets in CIA rats. RT-PCR/SSCP analysis showed that TCR Vbeta5.2 and TCR Vbeta8.2 clonotypes predominated in the T lymphocytes infiltrating in the joints of CIA rats. T lymphocytes infiltrating in the joints of the recipient rats displayed the same TCR Vbeta clonotypes as those in the donor rats. CONCLUSION: CIA rats may have a limited number of dominant TCR Vbeta clonotypes of T lymphocytes accumulating in the synovium, of which TCR Vbeta5.2 and 8.2 predominate.

Three trifluoromethyl-substituted protoporphyrinogen IX oxidase inhibitors.

The structures of methyl 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoate, C15H9ClF3N3O5, (I), methyl 2-chloro-5-[3-methyl-2,6-dioxo-4-(trifluoromethyl)-1,2,3,6-tetrahydropyrimidin-1-yl]benzoate, C14H10ClF3N2O4, (II), and 2-[4-chloro-2-fluoro-5-(prop-2-ynyloxy)phenyl]-4-(trifluoromethyl)piperidine-2,6-dione, C15H10ClF4NO3, (III), are similar in their dihedral angles and in the distances between the farthest two atoms. There are two independent molecules in the structure of (I). The dihedral angles between the two aromatic rings in each molecule in (I), between the benzene and tetrahydropyrimidine rings in (II), and between the benzene ring and the five-atom planar portion of the piperidine-2,6-dione ring in (III) are 80.78 (11)/89.75 (11), 89.13 (9) and 87.52 (13) degrees , respectively. The distances between the farthest two atoms, viz. O...F in the two molecules of (I), and Cl...F in (II) and (III), are 11.763 (7)/11.953 (6), 10.734 (10) and 10.889 (9) A, respectively. In all three crystal structures, the molecules are linked to generate sheets of molecules via C-H...O interactions.

A facile synthesis of novel herbicidal 1-phenyl-piperazine-2,6-diones.

Novel 1-phenyl-piperazine-2,6-diones were prepared by a new facile synthetic route using methyl N-substituted iminomonoacetate as starting material. The structures of these compounds were established by (1)H-NMR, (13)C-NMR and GC/MS. 2-(4-Chloro-5-cyclo-pentyl-oxy-2-fluorophenyl)-tetrahydro-2H-pyrido-[1,2-a]-pyrazine-1,3-(4H,6H)-dione displayed the greatest herbicidal activity.