1.Molecular characteristics and genetic evolution analysis of CRISPR loci in Listeria monocytogenes
DU Bo ; WU Ying ; CAI Nannan ; REN Yanyan ; XIU Min ; LIU Wenxin
China Tropical Medicine 2025;25(3):343-
Objective To detect clustered regularly interspaced short palindromic repeats (CRISPR) in Listeria monocytogenes, and analyze the structure and homology of CRISPR loci. Methods Totally 34 strains of Listeria monocytogenes isolated in our laboratory were identified, PCR amplified and sequenced. The repeat sequence structure and spacer sequence homology in CRISPR loci were analyzed by bioinformatics software. Results A total of 7 CRISPR loci were detected in 34 strains. The mutation rate of the first 2 and last 2 bases of the Repeat sequence of CRISPR loci was higher, while the mutation rate of the middle part was lower. Seven CRISPR sites form eight CRISPR structural types, among which the Repeat sequences of CRISPR1 and CRISPR2 are relatively conserved, while the Repeat sequences of CRISPR1 and CRISPR5 can form dumbbell shaped secondary structures. The number of Spacer sequences contained in each CRISPR site ranges from 2 to 15, with an average of 2.43. The 136 Spacer sequences detected were not only homologous to Listeria plasmids and bacteriophages, but also homologous to uncultured virus sequences, staphylococcal bacteriophages, and Listeria innocua. The same CRISPR genotype did not show large-scale clustering, but some strains in the same year were in the same evolutionary cluster with close genetic relationships. Conclusion The CRISPR structure of Listeria monocytogenes in this study exhibits high specificity, and its homology with bacteriophages provides a theoretical basis for the application of bacteriophages in the control and prevention of Listeria monocytogenes.
2.Myeloid-derived suppressor cells as important factors and potential targets for breast cancer progression.
Nannan DU ; Hua WAN ; Hailing GUO ; Xukuan ZHANG ; Xueqing WU
Journal of Zhejiang University. Medical sciences 2024;53(6):785-795
Recurrence and metastasis remain the leading cause of death in breast cancer patients due to the lack of effective treatment. A microenvironment suitable for cancer cell growth, referred to as pre-metastatic niche (PMN), is formed in distant organs before metastasis occurs. Myeloid-derived suppressor cells (MDSCs) are a heterogenous population of immature myeloid cells with immunosuppressive effects. They can expand in large numbers in breast cancer patients and participate in the formation of PMN. MDSCs can remodel the extracellular matrix of pulmonary vascular endothelial cells and recruit cancer stem cells to promote the lung metastasis of breast cancer. Furthermore, MDSCs facilitate immune evasion of breast cancer cells to impact the efficacy of immunotherapy. It is proposed that MDSCs represent a potential therapeutic target for the inhibition of recurrence and metastasis in breast cancer. Therapeutic strategies targeting MDSCs have shown promising efficacy in preclinical studies and clinical trials. This review presents a summary of the principal factors involved in the recruitment and activation of MDSCs during the formation of PMN, and outlines MDSCs functions such as immunosuppression and the current targeted therapies against MDSCs, aiming to provide new ideas for the treatment of distant metastases in breast cancer.
Humans
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Myeloid-Derived Suppressor Cells/immunology*
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Breast Neoplasms/immunology*
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Female
;
Tumor Microenvironment
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Disease Progression
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Immunotherapy/methods*
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Neoplasm Metastasis
;
Neoplastic Stem Cells
3.A fluorescence immunochromatography method for detection of human papillomavirus type 16 E6 and L1 proteins.
Xin'er LIU ; Yinzhen ZHAO ; Nannan NIU ; Lingke LI ; Xueli DU ; Jinxiang GUO ; Yingfu ZHANG ; Jichuang WANG ; Yiqing ZHANG ; Yunlong WANG
Chinese Journal of Biotechnology 2024;40(11):4266-4276
This study aims to establish a time-resolved fluorescence immunochromatography method for simultaneous determination of human papillomavirus (HPV) type 16 E6 and L1 protein concentrations. The amount of lanthanide microsphere-labeled antibodies, the concentration of coated antibodies, and the reaction time were optimized, and then a test strip for the simultaneous determination of the protein concentrations was prepared. The performance of the detection method was evaluated based on the concordance of the results from clinical practice. The optimal conditions were 8 μg and 10 μg of HPV16 L1 and E6-labeled antibodies, respectively, 1.5 mg/mL coated antibodies, and reaction for 10 min. The detection with the established method for L1 and E6 proteins showed the linear ranges of 5-320 ng/mL and 2-64 ng/mL and the lowest limits of detection of 1.78 ng/mL and 1.09 ng/mL, respectively. There was no cross reaction with human immunodeficiency virus (HIV), treponema pallidum (TP), or HPV18 E6 and L1 proteins. The average recovery rate of the established method was between 97% and 107%. The test strip prepared in this study showed the sensitivity, specificity, and diagnostic accuracy of 97.46%, 90.57%, and 95.32%, respectively, in distinguishing patients with cervical cancer and precancerous lesions from healthy subjects, with the area under the curve (AUC) of 0.980 1 and 95% Confidence Interval (CI) of 0.956 5 to 1.000 0. The time-resolved fluorescence immunochromatography combined with the test strips prepared in this study showed high sensitivity, high accuracy, simple operation, and rapid reaction in the quantitation of HPV16 E6 and L1 proteins. It thus can be used as an auxiliary method for the diagnosis and early screening of cervical cancer and precancerous lesions and the assessment of disease course.
Oncogene Proteins, Viral/immunology*
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Humans
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Chromatography, Affinity/methods*
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Female
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Human papillomavirus 16
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Repressor Proteins/immunology*
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Capsid Proteins/immunology*
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Papillomavirus Infections/diagnosis*
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Fluorescence
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Uterine Cervical Neoplasms/virology*
4.Altered white matter microarchitecture in Parkinson's disease: a voxel-based meta-analysis of diffusion tensor imaging studies.
Xueling SUO ; Du LEI ; Wenbin LI ; Lei LI ; Jing DAI ; Song WANG ; Nannan LI ; Lan CHENG ; Rong PENG ; Graham J KEMP ; Qiyong GONG
Frontiers of Medicine 2021;15(1):125-138
This study aimed to define the most consistent white matter microarchitecture pattern in Parkinson's disease (PD) reflected by fractional anisotropy (FA), addressing clinical profiles and methodology-related heterogeneity. Web-based publication databases were searched to conduct a meta-analysis of whole-brain diffusion tensor imaging studies comparing PD with healthy controls (HC) using the anisotropic effect size-signed differential mapping. A total of 808 patients with PD and 760 HC coming from 27 databases were finally included. Subgroup analyses were conducted considering heterogeneity with respect to medication status, disease stage, analysis methods, and the number of diffusion directions in acquisition. Compared with HC, patients with PD had decreased FA in the left middle cerebellar peduncle, corpus callosum (CC), left inferior fronto-occipital fasciculus, and right inferior longitudinal fasciculus. Most of the main results remained unchanged in subgroup meta-analyses of medicated patients, early stage patients, voxel-based analysis, and acquisition with 30 diffusion directions. The subgroup meta-analysis of medication-free patients showed FA decrease in the right olfactory cortex. The cerebellum and CC, associated with typical motor impairment, showed the most consistent FA decreases in PD. Medication status, analysis approaches, and the number of diffusion directions have an important impact on the findings, needing careful evaluation in future meta-analyses.
Anisotropy
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Brain/diagnostic imaging*
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Corpus Callosum
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Diffusion Tensor Imaging
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Humans
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Parkinson Disease/diagnostic imaging*
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White Matter/diagnostic imaging*
5.Prognostic factors analysis of Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction after radical resection with different surgical approaches
Yingxin DU ; Jingyu DENG ; Han LIANG ; Huifang LIU ; Weilin SUN ; Zizhen WU ; Jinyuan LIU ; Nannan ZHANG ; Zhenzhen ZHAO ; Liqiao CHEN
Chinese Journal of Digestive Surgery 2020;19(6):630-636
Objective:To investigate the prognostic factors of Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction (AEG) after radical resection with different surgical approaches.Methods:The retrospective case-control study was conducted. The clinicopathological data of 442 patients who were admitted to Tianjin Medical University Cancer Institute and Hospital from February 2003 to July 2011 were collected. There were 362 males and 80 females, aged from 21 to 85 years, with a median age of 64 years. Patients underwent radical resection of AEG. Observation indicators: (1) surgical situations; (2) follow-up; (3) progrostic factors analysis of AEG after radical resection; (4) survival of patients after radical resection of AEG via abdominal approach; (5) survival of patients after radical resection of AEG via thoracoabdominal approach; (6) survival of patients after radical resection of Siewert type Ⅱ type AEG; (7) survival of patients after radical resection of Siewert type Ⅲ AEG. Follow-up using outpatient examination and telephone interview was performed to detect postoperative survival of patients up to June 2018. Measurement data with skewed distribution were described as M (range). Count data were expressed as absolute numbers or percentages. Kaplan-Meier method was used to calculate survival rates and draw survival curves, and Log-rank test was used for survival analysis. Univariate analysis was conducted using the Kaplan-Meier method. Multivariate analysis was conducted using the COX proportional hazard model. Results:(1) Surgical situations: 442 patients underwent radical resection of AEG, including 204 via abdominal approach and 238 via thoracoabdominal approach. There were 391 patients with D 2 lymphadenectomy and 51 with D 2+ lymphadenectomy. (2) Follow-up: 442 patients were followed up for 8-162 months, with a median follow-up time of 37 months. All the 442 patients survived for 2-156 months, with a median survival time of 31 months. The 1-, 3-, 5-year overall survival rates were 79.2%, 42.0%, 30.0%, respectively. (3) Prognostic factors analysis of AEG after radical resection: results of univariate analysis showed that tumor diameter, Lauren type, pathological T staging, pathological N staging, pathological TNM staging, lymphatic vessel invasion, and soft tissue infiltration were related factors for prognosis of patients after radical resection of Siewert type Ⅱ and Ⅲ AEG ( χ2=4.028, 4.885, 19.435, 17.014, 34.449, 9.707, 11.866, P<0.05). Results of multivariate analysis showed that pathological TNM staging, lymphatic vessel invasion, and soft tissue infiltration were independent influencing fators for prognosis of patients after radical resection of Siewert type Ⅱ and Ⅲ AEG ( hazard ratio=1.255, 0.486, 1.454, 95% confidence interval: 1.024-1.539, 0.325-0.728, 1.096-1.928, P<0.05). (4) Survival of patients after radical resection of AEG via abdominal approach: of the 204 patients undergoing radical resection of AEG via abdominal approach, the 1-, 3-, 5-year survival rates were 83.6%, 50.4%, 37.8% for 121 patients with Siewert type Ⅱ AEG, respectively, versus 72.0%, 39.3%, 31.8% for 83 patients with Siewert type Ⅲ AEG, showing no significant difference in the survival between the two groups ( χ2=1.854, P>0.05). (5) Survival of patients after radical resection of AEG via thoracoabdominal approach: of the 238 patients undergoing radical resection of AEG via thoracoabdominal approach, the 1-, 3-, 5-year survival rates were 79.6%, 38.8%, 23.8% for 183 patients with Siewert type Ⅱ AEG, respectively, versus 79.1%, 37.6%, 29.3% for 55 patients with Siewert type Ⅲ AEG, showing no significant difference in the survival between the two groups ( χ2=0.215, P>0.05). (6) Survival of patients after radical resection of Siewert type Ⅱ AEG: of the 304 patients with Siewert typeⅡAEG, the postoperative 1-, 3-, 5-year survival rates were 83.6%, 50.4%, 37.8% for 121 patients undergoing radical resection of AEG via abdominal approach, respectively, versus 79.6%, 38.8%, 23.8% for 183 patients undergoing radical resection of AEG via thoracoabdominal approach, showing no significant difference in the survival between the two groups ( χ2=2.406, P>0.05). (7) Survival of patients after radical resection of Siewert type Ⅲ AEG: of the 138 patients with Siewert type Ⅲ AEG, the postoperative 1-, 3-, 5-year survival rates were 72.0%, 39.3%, 31.8% for 83 patients undergoing radical resection of AEG via abdominal approach, respectively, versus 79.1%, 37.6%, 29.3% for 55 patients undergoing radical resection of AEG via thoracoabdominal approach, showing no significant difference in the survival between the two groups ( χ2=0.640, P>0.05). Conclusions:Pathological TNM staging, lymphatic vessel invasion, and soft tissue infiltration are independent fators for prognosis of patients after radical resection of Siewert type Ⅱ and Ⅲ AEG. Siewert types and surgical approach are not related factors for prognosis of patients after radical resection of AEG. There is no significant difference in the survival between patients with different Siewert types of AEG undergoing radical resection via different surgical approaches.
6. Mechanism of curcumin in inhibiting silica-induced NLRP3 inflammasome activation in mouse alveolar macrophages
Nannan SONG ; Zhongjun DU ; Qiang JIA ; Shangya CHEN ; Wenwen ZHU ; Xu YANG ; Shanshan HOU ; Hua SHAO
China Occupational Medicine 2020;47(02):121-128
OBJECTIVE: To explore the molecular mechanism of curcumin in inhibiting the nucleotide-binding oligomerization domain like receptor family pyrin domain-containing(NLRP3) inflammatory bodies induced by silica(SiO_2) in mouse alveolar macrophages(AM). METHODS: AMs were isolated from the bronchoalveolar lavage fluid of specific pathogen free C57 BL/6 mice and divided into 6 groups. Among them, the AM of the control group received no stimulation; the AM in the SiO_2 stimulation group was stimulated with SiO_2 suspension at the final mass concentration of 50 mg/L; the AM in nuclear factor(NF-κB)inhibition group was pretreated with 5-(4-fluorophenyl)-2-urea-thiophene-3-formamide with a final concentration of 200 nmoL/L for 1 hour, the AM in the low-, medium-and high-dose curcumin groups were pretreated with curcumin with the final concentrations of 20, 40 and 50 μmol/L for 1 hour, respectively, and then stimulated with SiO_(2 )suspension with a final concentration of 50 mg/L. Samples were collected after 6 hours of incubation. The mRNA expression of NLRP3 inflammasome related genes such as NLRP3, Caspase-1 and interleukin(IL)-1β was detected by real-time fluorescence quantitative polymerase chain reaction. The secretion level of maturation IL-1β(mIL-1β) and IL-18 in AM was detected by enzyme-linked immunosorbent assay. The protein expression and secretion level of cleaved Caspase-1, precursor-IL-1β(pro-IL-1β) and mIL-1β were analyzed by Western blotting. RESULTS: The mRNA relative expression of NLRP3, Caspase-1 and IL-1β, and the secretion levels of mIL-1β and IL-18, and the protein relative expression of Caspase-1, pro-IL-1β and mIL-1β, as well as the secretion levels of cleaved Caspase-1 and mIL-1β increased in the SiO_2 stimulated group compared with the control group(P<0.05). Except for the relative expression and the secretion level of cleaved Caspase-1, the other 8 indexes in the NF-κB inhibition group were lower than that in the SiO_2 stimulation group(P<0.05). Except for the relative expression of cleaved Caspase-1 and mIL-1β proteins in the low-dose curcumin group, the relative expression of all the above 10 indexes was lower in the three curcumin treated groups than that in the SiO_2 stimulation group(P<0.05). In addition, all the above indexes decreased with the increase of curcumin intervention dose(P<0.05). The mRNA relative expression of NLRP3 and IL-1β, and the protein relative expression of pro-IL-1β increased in the medium-dose curcumin group(P<0.05), the secretion levels of mIL-1β and IL-18, as well as the protein relative expression and secretion levels of cleaved Caspase-1 and mIL-1β decreased(P<0.05), compared with the NF-κB inhibition group. CONCLUSION: Curcumin can inhibit SiO_2-induced AM NLRP3 inflammasome activation in a dose-response relationship. This process may be related to the inhibition of NF-κB signaling pathway by curcumin and the down-regulating NLRP3 inflammasome-related genes at the transcriptional level. The important mechanism may be that curcumin directly blocks the activation, assembly, and downstream shearing of NLRP3 in inflammasomes.
7.Clinical features and genetic analysis of a pedigree affected with non-muscle myosin heavy chain 9 gene related disease.
Qiangwu ZENG ; Yuanyuan HAN ; Ling HUANG ; Hongpei JI ; Youyan DU ; Nannan YANG ; Qin XU ; Sheng HUANG
Chinese Journal of Medical Genetics 2019;36(4):352-356
OBJECTIVE:
To identify the mutation type of non-muscle myosin heavy chain 9 (MYH9) gene and investigate the clinical features of a pedigree affected with MYH9 gene-related disease.
METHODS:
Peripheral blood samples of the proband and his family members were collected. Routine blood tests were performed, which included platelet counting and Wright's staining to observe the granulocyte inclusions and giant platelets. PCR was used to amplify exons 2, 17, 27, 31, 39 and 41 of the MYH9 gene, and the mutation site was determined by Sanger sequencing.
RESULTS:
All patients from the pedigree presented a typical triad of thrombocytopenia, giant platelets, and inclusion bodies in leukocytes. In addition, two patients had nephritis and cataract. All affected members carried a heterozygous missense mutation of c.5521G>A (p.glu1841Lys) in exon 39 of the MYH9 gene. The same mutation was not found among healthy members of the pedigree and the controls.
CONCLUSION
The c.5521G>A (p.Glu1841Lys) mutation in the MYH9 gene probably underlies the MYH9-related disease in this pedigree.
Female
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Genetic Testing
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Humans
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Male
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Molecular Motor Proteins
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genetics
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Mutation
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Myosin Heavy Chains
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genetics
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Pedigree
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Thrombocytopenia
8.White Matter Microstructural Similarity and Diversity of Functional Constipation and Constipation-predominant Irritable Bowel Syndrome
Jiaofen NAN ; Liangliang ZHANG ; Qiqiang CHEN ; Nannan ZONG ; Peiyong ZHANG ; Xing JI ; Shaohui MA ; Yuchen ZHANG ; Wei HUANG ; Zhongzhou DU ; Yongquan XIA ; Ming ZHANG
Journal of Neurogastroenterology and Motility 2018;24(1):107-118
BACKGROUND/AIMS: The Rome III criteria separated chronic constipation into functional constipation (FC) and constipation-predominant irritable bowel syndrome (IBS-C), but some researchers questioned the partitioning and treated both as distinct parts of a continuum. The study aims to explore the similarity and diversity of brain white matter between FC and IBS-C. METHODS: The voxel-wise analysis of the diffusion parameters was used to quantify the white matter changes of female brains in 18 FC patients and 20 IBS-C patients compared with a comparison group with 19 healthy controls by tract-based spatial statistics. The correlations between diffusive parameters and clinical symptoms were evaluated using a Pearson’s correlation. RESULTS: In comparison to healthy controls, FC patients showed a decrease of fractional anisotropy (FA) and an increase of radial diffusivity (RD) in multiple major fibers encompassing the corpus callosum (CC, P = 0.001 at peak), external capsule (P = 0.002 at peak), corona radiata (CR, P = 0.001 at peak), and superior longitudinal fasciculus (SLF, P = 0.002 at peak). In contrast, IBS-C patients showed FA and RD aberrations in the CC (P = 0.048 at peak). Moreover, the direct comparison between FC and IBS-C showed only RD differences in the CR and SLF. In addition, FA and RD in the CC were significantly associated with abdominal pain for all patients, whereas FA in CR (P = 0.016) and SLF (P = 0.040) were significantly associated with the length of time per attempt and incomplete evacuation separately for FC patients. CONCLUSION: These results may improve our understanding of the pathophysiological mechanisms underlying different types of constipation.
Abdominal Pain
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Anisotropy
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Brain
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Constipation
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Corpus Callosum
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Diffusion
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Diffusion Tensor Imaging
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External Capsule
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Female
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Humans
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Irritable Bowel Syndrome
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White Matter

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