Objective·To analyze the root canal diameter and taper of mandibular first molars using cone-beam CT(CBCT),investigate age-related changes in these parameters,and propose optimized clinical protocols for root canal preparation.Methods·From October 2022 to October 2023,CBCT images of 240 healthy mandibular first molars(120 three-canal type cases and 120 four-canal type cases)were collected from patients aged 20?59 years at the Stomatology Center,Haikou Affiliated Hospital of Central South University Xiangya School of Medicine.The three-canal type and the four-canal type samples were respectively divided into four age groups(20?29,30?39,40?49,and 50?59 years),with 30 cases in each group.Root canal length was measured,and buccolingual and mesiodistal diameters were recorded at four levels(coronal,middle,apical,and foramen).The tapers of the coronal 1/3,middle 1/3,and apical 1/3 segments were calculated in both buccolingual and mesiodistal directions.Differences among the age groups were compared.Results·The buccolingual diameters of all root canals exceeded the corresponding mesiodistal diameters.At several levels of most root canals,the diameters in the<50-year-old groups were significantly larger than those in the 50?59-year-old group(P<0.05).The buccolingual tapers exceeded the corresponding mesiodistal tapers in all root canals of mandibular first molars.The mean mesiodistal tapers in different age groups ranged from 0.07 to 0.34 in the coronal 1/3 segment,0.03 to 0.09 in the middle 1/3 segment,and 0.05 to 0.11 in the apical 1/3 segment.At several levels of most root canals,the tapers in the<50-year-old groups were significantly larger than those in the 50?59-year-old group(P<0.05).Conclusion·Mandibular first molars exhibit age-related narrowing of root canal diameter and reduced taper in individuals aged≥50 years.For initial apical file selection,#15 files are recommended for the distal canals in the three-canal type,while#10 files are advised for all other canals in the three-canal type and all canals in the four-canal type.For patients aged 50 years or older,the files for the distal canals in the three-canal type can be adjusted to#10,and the files for the mesiobuccal and distallingual canals in the four-canal type to#8.Regarding preparation taper,a 0.08-taper orifice opener is recommended for the coronal 1/3 segment.During mid-lower segment preparation,0.04-taper master apical files are suggested for the mesiobuccal and mesiolingual canals in the three-canal type and the mesiolingual and distallingual canals in the four-canal type,0.06-taper files for the distal canals in the three-canal type and the mesiobuccal canals in the four-canal type,and 0.08-taper files for the distobuccal canals in the four-canal type.Root canal obturation is recommended to be performed using vertical compaction with large-taper gutta-percha cones combined with bioceramic sealer.

Objective·To analyze the root canal diameter and taper of mandibular first molars using cone-beam CT(CBCT),investigate age-related changes in these parameters,and propose optimized clinical protocols for root canal preparation.Methods·From October 2022 to October 2023,CBCT images of 240 healthy mandibular first molars(120 three-canal type cases and 120 four-canal type cases)were collected from patients aged 20?59 years at the Stomatology Center,Haikou Affiliated Hospital of Central South University Xiangya School of Medicine.The three-canal type and the four-canal type samples were respectively divided into four age groups(20?29,30?39,40?49,and 50?59 years),with 30 cases in each group.Root canal length was measured,and buccolingual and mesiodistal diameters were recorded at four levels(coronal,middle,apical,and foramen).The tapers of the coronal 1/3,middle 1/3,and apical 1/3 segments were calculated in both buccolingual and mesiodistal directions.Differences among the age groups were compared.Results·The buccolingual diameters of all root canals exceeded the corresponding mesiodistal diameters.At several levels of most root canals,the diameters in the<50-year-old groups were significantly larger than those in the 50?59-year-old group(P<0.05).The buccolingual tapers exceeded the corresponding mesiodistal tapers in all root canals of mandibular first molars.The mean mesiodistal tapers in different age groups ranged from 0.07 to 0.34 in the coronal 1/3 segment,0.03 to 0.09 in the middle 1/3 segment,and 0.05 to 0.11 in the apical 1/3 segment.At several levels of most root canals,the tapers in the<50-year-old groups were significantly larger than those in the 50?59-year-old group(P<0.05).Conclusion·Mandibular first molars exhibit age-related narrowing of root canal diameter and reduced taper in individuals aged≥50 years.For initial apical file selection,#15 files are recommended for the distal canals in the three-canal type,while#10 files are advised for all other canals in the three-canal type and all canals in the four-canal type.For patients aged 50 years or older,the files for the distal canals in the three-canal type can be adjusted to#10,and the files for the mesiobuccal and distallingual canals in the four-canal type to#8.Regarding preparation taper,a 0.08-taper orifice opener is recommended for the coronal 1/3 segment.During mid-lower segment preparation,0.04-taper master apical files are suggested for the mesiobuccal and mesiolingual canals in the three-canal type and the mesiolingual and distallingual canals in the four-canal type,0.06-taper files for the distal canals in the three-canal type and the mesiobuccal canals in the four-canal type,and 0.08-taper files for the distobuccal canals in the four-canal type.Root canal obturation is recommended to be performed using vertical compaction with large-taper gutta-percha cones combined with bioceramic sealer.

Objective:To study the distribution and antibiotics resistance of the main pathogens of neonatal purulent meningitis in different regions of China.Methods:A retrospective descriptive clinical epidemiological study was conducted in children with neonatal purulent meningitis which admitted to 18 tertiary hospitals in different regions of China between January 2015 to December 2019. The test results of blood and cerebrospinal fluid, and drug sensitivity test results of the main pathogens were collected. The distributions of pathogenic bacteria in children with neonatal purulent meningitis in preterm and term infants, early and late onset infants, in Zhejiang Province and other regions outside Zhejiang Province, and in Wenzhou region and other regions of Zhejiang Province were analyzed. The chi-square test was used for statistical analysis.Results:A total of 210 neonatal purulent meningitis cases were collected. The common pathogens were Escherichia coli ( E. coli)(41.4%(87/210)) and Streptococcus agalactiae ( S. agalactiae)(27.1%(57/210)). The proportion of Gram-negative bacteria in preterm infants (77.6%(45/58)) with neonatal purulent meningitis was higher than that in term infants (47.4%(72/152)), and the difference was statistically significant ( χ2=15.54, P=0.001). There were no significant differences in the constituent ratios of E. coli (36.5%(31/85) vs 44.8%(56/125)) and S. agalactiae (24.7%(21/85) vs 28.8%(36/125)) between early onset and late onset cases (both P>0.05). The most common pathogen was E. coli in different regions, with 46.7%(64/137) in Zhejiang Province and 31.5%(23/73) in other regions outside Zhejiang Province. In Zhejiang Province, S. agalactiae was detected in 49 out of 137 cases (35.8%), which was significantly higher than other regions outside Zhejiang Province (11.0%(8/73)). The proportions of Klebsiella pneumoniae, and coagulase-negative Staphylococcus in other regions outside Zhejiang Province (17.8%(13/73) and 16.4%(12/73)) were both higher than those in Zhejiang Province (2.9%(4/137) and 5.1%(7/137)). The differences were all statistically significant ( χ2=14.82, 12.26 and 7.43, respectively, all P<0.05). The proportion of Gram-positive bacteria in Wenzhou City (60.8%(31/51)) was higher than that in other regions in Zhejiang Province (38.4%(33/86)), and the difference was statistically significant ( χ2=6.46, P=0.011). E. coli was sensitive to meropenem (0/45), and 74.4%(32/43) of them were resistant to ampicillin. E. coli had different degrees of resistance to other common cephalosporins, among which, cefotaxime had the highest resistance rate of 41.8%(23/55), followed by ceftriaxone (32.4%(23/71)). S. agalactiae was sensitive to penicillin, vancomycin and linezolid. Conclusions:The composition ratios of pathogenic bacteria of neonatal purulent meningitis are different in different regions of China. The most common pathogen is E. coli, which is sensitive to meropenem, while it has different degrees of resistance to other common cephalosporins, especially to cefotaxime.

Objective::This study aimed to investigate the immune response of a pregnant woman who recovered from the coronavirus disease 2019 (COVID_RS) by using single-cell transcriptomic profiling of peripheral blood mononuclear cells (PBMCs) and to analyze the properties of different immune cell subsets.Methods::PBMCs were collected from the COVID_RS patient at 28 weeks of gestation, before a cesarean section. The PBMCs were then analyzed using single-cell RNA sequencing. The transcriptional profiles of myeloid, T, and natural killer (NK) cell subsets were systematically analyzed and compared with those of healthy pregnant controls from a published single-cell RNA sequencing data set.Results::We identified major cell types such as T cells, B cells, NK cells, and myeloid cells in the PBMCs of our COVID_RS patient. The increase of myeloid and B cells and decrease of T cells and NK cells in the PBMCs in this patient were quite distinct compared with that in the control subjects. After reclustering and Augur analysis, we found that CD16 monocytes and mucosal-associated invariant T (MAIT) cells were mostly affected within different myeloid, T, and NK cell subtypes in our COVID_RS patient. The proportion of CD16 monocytes in the total myeloid population was increased, and the frequency of MAIT cells in the total T and NK cells was significantly decreased in the COVID-RS patient. We also observed significant enrichment of gene sets related to antigen processing and presentation, T-cell activation, T-cell differentiation, and tumor necrosis factor superfamily cytokine production in CD16 monocytes, and enrichment of gene sets related to antigen processing and presentation, response to type II interferon, and response to virus in MAIT cells.Conclusion::Our study provides a single-cell resolution atlas of the immune gene expression patterns in PBMCs from a COVID_RS patient. Our findings suggest that CD16-positive monocytes and MAIT cells likely play crucial roles in the maternal immune response against severe acute respiratory syndrome coronavirus 2 infection. These results contribute to a better understanding of the maternal immune response to severe acute respiratory syndrome coronavirus 2 infection and may have implications for the development of effective treatments and preventive strategies for the coronavirus disease 2019 in pregnant women.

Objective::This study aimed to investigate the immune response of a pregnant woman who recovered from the coronavirus disease 2019 (COVID_RS) by using single-cell transcriptomic profiling of peripheral blood mononuclear cells (PBMCs) and to analyze the properties of different immune cell subsets.Methods::PBMCs were collected from the COVID_RS patient at 28 weeks of gestation, before a cesarean section. The PBMCs were then analyzed using single-cell RNA sequencing. The transcriptional profiles of myeloid, T, and natural killer (NK) cell subsets were systematically analyzed and compared with those of healthy pregnant controls from a published single-cell RNA sequencing data set.Results::We identified major cell types such as T cells, B cells, NK cells, and myeloid cells in the PBMCs of our COVID_RS patient. The increase of myeloid and B cells and decrease of T cells and NK cells in the PBMCs in this patient were quite distinct compared with that in the control subjects. After reclustering and Augur analysis, we found that CD16 monocytes and mucosal-associated invariant T (MAIT) cells were mostly affected within different myeloid, T, and NK cell subtypes in our COVID_RS patient. The proportion of CD16 monocytes in the total myeloid population was increased, and the frequency of MAIT cells in the total T and NK cells was significantly decreased in the COVID-RS patient. We also observed significant enrichment of gene sets related to antigen processing and presentation, T-cell activation, T-cell differentiation, and tumor necrosis factor superfamily cytokine production in CD16 monocytes, and enrichment of gene sets related to antigen processing and presentation, response to type II interferon, and response to virus in MAIT cells.Conclusion::Our study provides a single-cell resolution atlas of the immune gene expression patterns in PBMCs from a COVID_RS patient. Our findings suggest that CD16-positive monocytes and MAIT cells likely play crucial roles in the maternal immune response against severe acute respiratory syndrome coronavirus 2 infection. These results contribute to a better understanding of the maternal immune response to severe acute respiratory syndrome coronavirus 2 infection and may have implications for the development of effective treatments and preventive strategies for the coronavirus disease 2019 in pregnant women.

Constrained spherical deconvolution can quantify white matter fiber orientation distribution information from diffusion magnetic resonance imaging data. But this method is only applicable to single shell diffusion magnetic resonance imaging data and will provide wrong fiber orientation information in white matter tissue which contains isotropic diffusion signals. To solve these problems, this paper proposes a constrained spherical deconvolution method based on multi-model response function. Multi-shell data can improve the stability of fiber orientation, and multi-model response function can attenuate isotropic diffusion signals in white matter, providing more accurate fiber orientation information. Synthetic data and real brain data from public database were used to verify the effectiveness of this algorithm. The results demonstrate that the proposed algorithm can attenuate isotropic diffusion signals in white matter and overcome the influence of partial volume effect on fiber direction estimation, thus estimate fiber direction more accurately. The reconstructed fiber direction distribution is stable, the false peaks are less, and the recognition ability of cross fiber is stronger, which lays a foundation for the further research of fiber bundle tracking technology.
Brain ; White Matter/diagnostic imaging* ; Diffusion Magnetic Resonance Imaging/methods* ; Algorithms ; Databases, Factual ; Image Processing, Computer-Assisted/methods*

Objective:To explore accurate prenatal diagnosis, full-coverage graded counseling and follow-up for the fetus with cardiac birth defects (CBD).Methods:CBD fetus diagnosed prenatal by echocardiography from January 2018 to December 2020 in Guangdong Provincial People's Hospital were enrolled. Fetal CBD was graded (Ⅰ-Ⅵ) according to prognosis and possible operation time after birth, and the classification criteria and common diseases included were proposed. After the prenatal grading counseling, the outcome of the fetus was followed-up. The induced labor rate, live birth rate, prenatal and postnatal ultrasound diagnosis coincidence rate and other indicators were calculated. The disease composition ratio, prognosis of fetus with different grades and the outcome of integrated treatment were analyzed.Results:The detection rate of fetal CBD was up to 16.2% (1 971/12 188), 30 cases of which were excluded. A total of 1 941 cases were included in this study, including 196 cases (10.1%) of gradeⅠ, 433 cases (22.3%) of gradeⅡ, 615 cases (31.7%) of grade Ⅲ, 261 cases (13.4%) of grade Ⅳ, 388 cases (20.0%) of gradeⅤ, 48 cases (2.5%) of grade Ⅵ. Grade Ⅱ and gradeⅢ (the operation time was within 1 year after birth) accounted for 54.0% (1 048/1 941). The distribution of some diseases in different grades had obvious proportion advantage, which was representative. Among 1 747 CBD fetus, 736 cases (induced labor rate 42.1%) chose to terminate pregnancy due to CBD. Of the 1 010 live births, 975 cases (96.5%) had the same prenatal and postnatal diagnosis, 3 cases were missed diagnosis and 32 cases were misdiagnosed. The diagnostic accuracy of live births with severe and complex congenital heart disease was 383 out of 389 (98.5%). A total of 258 cases have received surgery or intervention. The age at the time of surgery or intervention was different among grades（ χ2 =47.3， P<0.001）. With the improvement of prognosis from gradeⅠ to Ⅴ, the live birth rate increased and the induced labor rate decreased accordingly; the difference between grades was significant（ χ2 =623.6， P<0.001）. Conclusions:Prenatal diagnosis and graded counseling is important in the integrated model. Fetal CBD grading could refine post-natal treatment strategies, guide delivery decisions and become an evaluation standard.

Aim To explore the mechanisms of the apoptosis induction and the effects of adhesion suppression of Zhiling capsule (ZLJN) in small cell lung cancer cell line NCI-H446.Methods According to the different components of ZLJN,NCI-H446 cells were treated with traditional Chinese medicine,western medicine and ZLJN composite groups.Apoptotic cells were tested by light microscopy,Hochest33258 staining method.The mRNA and protein expressions of bcl-2,bax and hTERT were analyzed by RT-PCR and Western blot respectively.The expressions of CD44 were detected by flow cytometry.Results After NCI-H446 cells were treated with different drug groups,The morphological changes of apoptotic cells were found by light microscopy and Hochest33258 staining method.The mRNA and protein expressions of bcl-2 were down-regulated while the expressions of bax were up-regulated compared to the control groups(P

Aim To investigate the effects of Zhiling capsule (ZLJN) on the proliferation inhibition and apoptosis induction in K562 cell line.Methods According to the different components of ZLJN,K562 cells were treated respectively with tradtional Chinese medicine,Western medicine and ZLJN compound groups.The cell viability and colony formation were observed by MTT assay and colony formation assay respectively.Apoptotic cells were detected by Annexin V-FITC/PI staining and DNA fragmentation assay.Caspase-3 activity was detected by flow cytometry,and pro-caspase-3 was detected by Western blot.Results Treated with drug,K562 cell growth and cell colony formation were significantly inhibited.Apoptosis occurring in the early stage was identified by Annexin V-FITC/PI staining.Typical DNA ladder was seen from gel electrophoresis and apparent apoptotic peaks were observed by flow cytometer.The level of caspase-3 activity increased after the treatment,while the level of pro-caspase-3 decreased.Conclusion ZLJN can efficiently inhibit proliferation and induce apoptosis in K562 cells,which may be related with the up-regulation of caspase-3 activity.