Micro-computed tomography analysis of calcium hydroxide delivery efficacy in C-shaped canal system of mandibular second molars.

BACKGROUND: Calcium hydroxide [Ca(OH)2] is widely accepted as a biocompatible interappointment intracanal medicament. This study aimed to analyze the efficacy of Ca(OH)2 placement into the C-shaped canal system of mandibular second molars using the syringe method with and without lentulo spiral utilizing micro-computed tomography (micro-CT). METHODS: Twenty-four extracted mandibular second molars were instrumented and classified into C-shaped floors (n = 12) and non-C-shaped floors (n = 12). Both groups were placed with Ca(OH)2 using the syringe system, then all teeth were scanned and cleaned, and placed with Ca(OH)2 again but with the syringe system followed by lentulo spiral and rescanned. The specimens were scanned using micro-CT to analyze the volume, volume percentage, uncontacted surface area, and uncontacted surface area percentage of Ca(OH)2 with the two delivery methods in the entire canal and at the apical 4 mm of the canal. Mann-Whitney test and Wilcoxon signed-rank test were used to determine the statistical differences among the groups. RESULTS: Syringe administration used in conjunction with lentulo spiral presented lower uncontacted surface area, a lower percentage of uncontacted surface area, larger volume, and a higher percentage of volume than syringe without lentulo spiral (P < 0.05). There was no significant difference between the C-shaped floor group and the non-C-shaped floor group (P > 0.05) in the Ca(OH)2 uncontacted surface area, volume, and percentages at different regions of canals and among different delivery techniques groups. CONCLUSIONS: The lentulo spiral and syringe technique combination can increase the volume and contacted surface area of Ca(OH)2 in the C-shaped canal system of mandibular second molars.

Definition of a Novel Immunogenic Cell Death-Relevant Gene Signature Associated with Immune Landscape in Gastric Cancer.

Immunogenic cell death (ICD) induces anti-tumor immunity and aids in dismantling the immunosuppressive immune microenvironment (TME), which belongs to a type of regulated cell death. The differentiation of gastric cancer (GC) subtypes and the discovery of prognostic biomarkers are crucial for its treatment because GC is a disease that is both highly heterogeneous and aggressive. However, although the induction of ICD in tumor cells is associated with a favorable prognosis, the exact mechanism of its role in GC remains unclear. Transcriptome profiling data and clinical data of GC patients were retrieved from The Cancer Genome Atlas (TCGA) database. Herein, patients were classified with the consensus clustering algorithm, and the associated biological functions and immune microenvironment infiltration were explored based on the expression of ICD-associated genes. A risk score signature consisting of 11 ICD-related genes was established via the least absolute shrinkage and selection operator regression (LASSO) method. We have retrieved similar studies in recent years and compared them with our study using the time-dependent receiver operating characteristic (ROC) curves. Gene set variation analysis (GSVA) and single sample gene set enrichment analysis (ssGSEA) were performed to explore the association between the signature and tumor microenvironment (TME). Two distinct subtypes associated with ICD in GC were identified, each with a different prognosis. The ICD-high expression subtype was associated with higher immune cell infiltration and a better prognosis. The ICD-related gene signature containing 11 genes (CGB5, Z84468.1, APOA5, EPHA8, CLEC18C, TLR7, MUC7, MUC15, CTLA4, CALB2, and UGT2B28), could independently and accurately predict the prognosis of GC. In this study, an ICD-based classification was conducted to assist in the diagnosis and personalized therapy for GC. The ICD-related genes risk score model was established to predict prognosis.

Mechano-chemical coupling of irrigation enhances endodontic biofilm debridement.

The complexity of the root canal system results in areas where mechanical instrumentation is impossible during endodontic treatment. To disinfect these areas, the effect of irrigation on biofilm debridement is of great significance but has not yet been well explored. Using an in vitro Enterococcus faecalis biofilm model and a biofilm reactor, the present study provides a better understanding of the relative contributions of mechanical and chemical effects of irrigation on biofilm removal, as well as the factors influencing their coupling efficiency. The results clearly demonstrate that, the mechanical effect of irrigation alone does not significantly influence the stability of biofilms. However, the mechanical effect promotes biofilm eradication by coupling with the chemical effect. In addition, both the irrigant concentration and the irrigant-biofilm contact time are among the key factors affecting the mechano-chemical coupling. This knowledge may serve to better direct endodontists in designing irrigation regimes during root canal therapy.

Microcomputed tomographic investigation of the trepan bur/microtube technique for the removal of fractured instruments from root canals without a dental operating microscope.

OBJECTIVES: The aim of this study was to evaluate the removal of fractured instruments in mandibular incisor canals by using the trepan bur/microtube technique without a dental operating microscope (DOM). MATERIALS AND METHODS: Thirty-four mandibular incisors were selected, and 5-mm apical segments of #25/.06 taper K3 NiTi instruments were fractured in the apical portion of each canal. Coronal enlargement was performed, and a staging platform was prepared at the coronal aspect of the fractured instrument. Then, a trepan bur was used to expose 1-1.5 mm of the fragmented instrument, and a microtube device was used to withdraw the fragment. Microcomputed tomographic (micro-CT) imaging was used to evaluate the geometric changes in the root canal and dentin. The time required for fractured instrument removal in each sample was recorded, and the results were statistically analyzed with a paired t test. RESULTS: The trepan bur/microtube technique exhibited a success rate of 76.47%, and the average fractured instrument removal time was 8.55 ± 5.81 min. The changes in canal volume and dentin volume from the coronal end of the fractured instrument to 1.5 mm apical to the end were significantly greater than those from the cementoenamel junction (CEJ) to the coronal end of the fractured instrument during fractured instrument removal (P < 0.0001). CONCLUSIONS: The study showed that the trepan bur/microtube technique had a significant impact on geometric changes in the root canal and dentin from the coronal end of the fractured instrument to 1.5 mm apical to the end. CLINICAL RELEVANCE: These findings suggest that the trepan bur/microtube technique may be an optional method for fractured instrument removal from relatively straight canals.

Internal and external morphological analysis of fused-rooted mandibular second molars in the Chinese population: A micro-computed tomographic study.

This study investigated the root canal morphology of fused-rooted mandibular second molars based on the pulp chamber floor (PCF) and analysed the correlation between the external morphology of the radicular groove, and the internal morphology of the PCF and root canal configuration. A total of 291 fused-rooted teeth collected from the Chinese population were scanned using micro-computed tomography and a dental operating microscope was used for observing the PCFs. The classification of the PCF and root canal configuration were identified according to modified Min et al.'s and Gao et al.'s classifications, respectively. Additionally, a new radicular groove classification was proposed. The correlation among these morphological characteristics was investigated using the chi-square test and Fisher's exact test (p < 0.05). The results showed that 74.2% of teeth had C-shaped PCFs, while 21.0% had non-C-shaped PCFs. As for the root canal configurations, 37.5% of teeth were merging type, 40.9% were symmetrical type, and 14.8% were asymmetrical type. Statistical analysis revealed a significant correlation between the PCF types and the root canal configurations (p < 0.001). The dominant root canal types for teeth with C-shaped PCFs were merging and symmetrical types, while the asymmetrical type was not identified in non-C-shaped PCFs. In addition, significant morphological association between the root canals and radicular grooves was also revealed (p < 0.001). Teeth with different PCF morphologies exhibit specific patterns of root canal category distribution. Understanding the morphological nuances of the root canal based on the PCF can assist clinicians in predicting and identifying the canal configuration beneath the visible orifice.

Comprehensive analysis of the tumor-promoting effect and immune infiltration correlation MAZ from pan-cancer to hepatocellular carcinoma.

BACKGROUND: Myc-associated zinc-finger protein (MAZ) is a transcription factor, which has been confirmed to be abnormally expressed in many tumors and involved in regulating the proliferation, migration, apoptosis, and autophagy of tumor cells. Currently, there is a lack of comprehensive analysis of MAZ in pan-cancer, and the mechanism of MAZ in hepatocellular carcinoma (HCC) and its association with immunotherapy remains unclear. METHODS: The expression, prognostic mutation, sCNA, and tumor immunity characteristics of MAZ in 33 types of tumors were analyzed by The Cancer Genome Atlas (TCGA), GEPIA, and TIMER databases. The association of MAZ expression levels with drug sensitivity, immunotherapy, immune checkpoints, and HLA-associated genes was further analyzed. Transwell, CCK-8, wound healing, and flow cytometry verified that MAZ affected the malignant cell behavior of HCC. The signaling pathways and cellular functions affected by MAZ in HCC were revealed by GSEA enrichment analysis. RESULTS: The expression level of MAZ was up-regulated, and the high expression of MAZ indicated a high-risk prognostic factor in most tumors, including ACC, BLCA, KIRP, LIHC, PRAD, SKCM, and THCA (p < 0.05). MAZ expression was positively correlated with the sensitivity of most chemotherapy drugs (p < 0.05). HLA-DQB2, HLA-H, and most immune checkpoint genes were remarkably up-regulated in the high MAZ expression group (p < 0.05). GSEA analysis revealed that MAZ expression was highly correlated with the intracellular immune-related functions and cancer-related signaling pathway, including the B cell receptor signaling pathway, complement activation, humoral immune response, TGF-ß signaling pathway, and Wnt signaling pathway. The overexpression of MAZ in HCC cells could promote the abilities of cell proliferation and migration and inhibit tumor cell apoptosis. CONCLUSION: Our study revealed that MAZ might play a role in promoting the progression of HCC. It was closely related to the tumor microenvironment, immune cell infiltration, and immune escape in pan-cancer. Moreover, this study provides new insights into MAZ as a prognostic marker and potential therapeutic target in HCC.

Prognostic and clinicopathological values of LINC00665 in cancers: a systematic review and China population-based meta-analysis.

BACKGROUND: Recent studies have uncovered that the aberrant expression of LINC00665 contributes to the malignant pathological process of various cancers and is closely related to the unfavorable prognosis of patients with cancer. However, a systematic analysis of the prognostic and clinicopathologic values of LINC00665 in cancers has not been conducted. OBJECTIVE: We aim to clarify the association of LINC00665 expression with patient survival and clinicopathologic phenotypes in cancers. METHODS: An electronic search of PubMed, Embase and Web of Science was performed to select eligible literature. Pooled hazard ratio (HR) and odds ratio (OR) were calculated to assess the clinical importance of LINC00665. The fixed-effects model was used to analyze the combined HR values and 95% CI when the studies had no significant heterogeneity (P > 0.1 for the Chi-square test or I2 < 50%). Begg's test and sensitivity analysis were also conducted. This study was registered in The International Prospective Register of Systematic Reviews (PROSPERO registration number: CRD42021290123). RESULTS: A total of 710 patients from 10 eligible studies were enrolled in this meta-analysis, which was based on China population. The pooled results of this analysis revealed that high-level expression of LINC00665 was notably correlated with poor overall survival (HR = 2.08, 95% CI = 1.57-2.75) and recurrence-free survival (HR = 2.49, 95% CI = 1.63-3.80) in human cancers. Elevated LINC00665 expression was also correlated with more advanced clinical stage, earlier lymph node metastasis, lower tumor differentiation, earlier distant metastasis and larger tumor size. CONCLUSION: LINC00665 expression was critically related to the cancer prognosis, which has important prognostic implications for clinical prediction.

Comprehensive analysis of basement membrane and immune checkpoint related lncRNA and its prognostic value in hepatocellular carcinoma via machine learning.

Background: Hepatocellular carcinoma (HCC), which is characterized by its high malignancy, generally exhibits poor response to immunotherapy. As part of the tumor microenvironment, basement membranes (BMs) are involved in tumor development and immune activities. Presently, there is no integrated analysis linking the basement membrane with immune checkpoints, especially from the perspective of lncRNA. Methods: Based on transcriptome data from The Cancer Genome Atlas, BMs-related and immune checkpoint-related lncRNAs were identified. By applying univariable Cox regression and Machine learning (LASSO and SVM-RFE algorithm), a 10-lncRNA prognosis signature was constructed. The prognostic significance of this signature was assessed by survival analysis. GSEA, ssGSEA, and drug sensitivity analysis were conducted to investigate potential functional pathways, immune status, and clinical implications of guiding individual treatments in HCC. Finally, the promoting migration effect of LINC01224 was validated via in vitro experiments. Results: The multiple Cox regression, receiver operating characteristic curves, and stratified survival analysis of clinical subgroups exhibited the robust prognostic ability of the lncRNA signature. Results of the GSEA and drug sensitivity analysis revealed significant differences in potential functional pathways and response to drugs between the two risk groups. In addition, the risk level of HCC patients was distinctly correlated with immune cell infiltration status. More importantly, LINC01224 was independently associated with the OS of HCC patients (P < 0.05), suppressing the expression of LINC01224 inhibited the migration of HCC cells. Conclusion: This study developed a reliable signature for the prognosis of HCC based on BM and immune checkpoint related lncRNA, revealing that LINC01224 might be a prognostic biomarker for HCC associated with the progression of HCC.

Prognostic Implication of a Cuproptosis-Related miRNA Signature in Hepatocellular Carcinoma.

Background: Hepatocellular carcinoma (HCC) is one of the most frequently diagnosed malignancies globally, accounting for the third cause of cancer mortality. Cuproptosis, a copper-induced cell death, was recently reported in Science. The purpose of this study was to evaluate the prognostic implication of cuproptosis-related miRNAs (CRMs) in HCC. Methods: Transcriptomic data and clinicopathological features of patients with HCC were extracted from the Cancer Genome Atlas (TCGA) database. Prognostic CRM signature was established by utilizing univariate Cox regression and LASSO analyses. To validate the accuracy of prediction, the Kaplan-Meier (K-M) and time-dependent receiver operating characteristic (ROC) analyses were adopted. A nomogram comprising clinical characteristics and the miRNA signature was developed to improve the prediction of patient outcomes. Finally, functional enrichment analysis and immune infiltration analysis were carried out. Results: Of CRMs, 14 were obtained to construct a prognostic miRNA signature. This CRM signature was an independent factor for predicting overall survival (OS). Kaplan-Meier curves demonstrated a noteworthy difference in survival rates between different risk subgroups (p < 0.001). The robust prognostic capacity of this signature was exhibited by sampling verification and stratified survival analysis. Functional analysis indicated that the high-risk group was mainly enriched in signaling pathways and different levels of immune infiltration were revealed between the two risk groups. The potential interaction of the model with the immune checkpoint activities was also detected. Conclusion: The CRM signature could act as an independent predictor to guide individual treatment strategies, which could provide fundamental insights for further studies.

[Quality of life and hostile mentality trend among 299 patients living with HIV/AIDS].

OBJECTIVE: To assess the quality of life (QOL) and hostile mentality trend (HMT) of 299 patients living with HIV/AIDS (Human immunodeficiency virus/Acquired immune deficiency syndrome) in three provinces in China, and to understand the major concerns of the these patients. METHODS: The SF-36 (short form -36) was used for assessing the QOL among 299 HIV-infected patients in Sichuan, Hubei and Guizhou provinces. Reliability and validity of SF-36 were evaluated. Consulting with experts and professionals, seven additional items were developed to evaluate the HMT. Mean scores of the 8 scales were compared between the patients and general rural residents in Sichuan province. RESULTS: For SF-36, internal consistent coefficients (Cronbach's alpha) of the 8 scales were between 0.75 to 0.90, test-retest reliability coefficient ranged from 0.54 to 0.80. The item-subscale correlation coefficients ranged from 0.46 to 0.97. Mean scores of the 8 scales of the patients ranged from 28.50 to 77.87, and 70.27 to 91.87 for the general rural residents. The variations of the scales were tested by means of Mann-Whitney test with u value ranged from -17.43 to -23.87. The QOL of the patients living with HIV/AIDS were significantly inferior to those of general population (all P < 0.01). The mean scores of the seven items to evaluate HMT ranged from 46.21 to 82.89. The major concerns of the patients living with HIV/AIDS included financial insecurity and family responsibilities, followed by death threat and no cure of HIV/AIDS. CONCLUSION: The SF-36 is a reliable instrument for assessing QOL of patients living with HIV/AIDS. The QOL of the patients living with HIV/AIDS in China is poor.

[Using the SF-36 to assess the quality of life of people living with HIV in Sichuan].

OBJECTIVE: To test the reliability and validity of the SF-36 in assessing the quality of life of people living with HIV in Sichuan province. METHODS: A questionnaire survey was undertaken in 114 people living with HIV in Dazhu and Zizhong county of Sichuan, which included the SF-36 for assessing quality of life and additional items for assessing the hostility mentality trend. A repeated survey was undertaken two weeks later in 40 out of the 114 respondents to evaluate the retest reliability of the questionnaire. The quality of life of the people living with HIV was assessed against the norm of 1604 rural residents in Sichuan. RESULTS: The internal consistent coefficients (Cronbach's alpha) of the eight scales of the SF-36 ranged from 0. 75 to 0. 92. The test-retest reliability coefficients of the eight scales of the SF-36 ranged from 0. 53 to 0. 83. The respondents who reported worse health scored significantly lower in all of the eight scales. The factor analysis extracted eight scales, with only four items without a dominant factor load on its corresponding scales. The average scores of the people living with HIV for the eight scales ranged from 21. 4 to 61. 0, significantly lower than the norm of the general rural residents. Age, gender, and length of infection were the major factors that impacted the quality of life of people living with HIV. It was common for the people living with HIV felt being stigmatized and dissatisfied with live. CONCLUSION: HIV infection deteriorates people's quality of life and the SF-36 is a valid instrument to assess the quality of life of people living with HIV.

[Determination of trace thallium by platform-GFAAS after preconcentration with polyurethane foam].

OBJECTIVE: To develop a method for trace thallium determination. METHODS: Thallium (L) was oxidized to thallium (III) by bromine water and the thallium (III) was complexed to [TlCl4]- in 20 mL/100 mL HCI and absorbed by polyurethane foam. The adsorbed thallium was eluted by a boiling water bath and determined by platform-GFAAS. Tl (III) could be analyzed directly and the total Tl be analyzed after oxidation, so speciation could be achieved. RESULTS: In the range of 5-100 ng/mL the linear equation was y = 0.013x + 0. 012 with the regression coefficient 0.996. The relative standard deviation was 4.7% for the standard solution of 5.00 ng/mL and the recoveries of water samples were in the range of 95.7%-104.5%. CONCLUSION: The proposed method could determine trace thallium as low as 0.02 ng/mL.

Quality of life and hostile mentality trend of patients with HIV/AIDS in China.

OBJECTIVE: To assess the quality of life (QOL) and hostile mentality trend (HMT) of patients with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) in China, and to identify their major concerns. STUDY DESIGN AND METHODS: Short Form-36 (SF-36) was used to assess QOL, and seven items were developed to assess the HMT. In-depth interviews were conducted with patients and health workers. RESULTS: SF-36 had moderate reliability, with Cronbach's alpha coefficients ranging from 0.75 to 0.90 and test-retest correlation coefficients ranging from 0.54 to 0.80 for the eight domains. The item-subscale correlation coefficients ranged from 0.46 to 0.97. The QOL of patients with HIV/AIDS was significantly lower than the average QOL of the general population (P<0.01). Hostile mentality of patients was significant (mean scores of the seven items ranged from 2.87 to 4.32, and the mean sum of scores was 3.45 from a range of 1-5). Cronbach's alpha coefficient of HMT items was 0.75 and the test-retest correlation coefficient was 0.80. The major concerns of patients with HIV/AIDS were financial insecurity and family responsibilities, followed by the fear of death and no cure for HIV/AIDS. CONCLUSION: SF-36 is a reliable instrument for the assessment of QOL of patients with HIV/AIDS. The QOL of patients with HIV/AIDS in China is poor. The HMT is a valuable indicator to monitor the outcomes of care for patients with HIV/AIDS.

[The development and assessment on an instrument regarding quality of life for patients living with HIV/AIDS in China].

OBJECTIVE: To develop a specific quality of life (QOL) instrument for Chinese patients living with HIV/AIDS and to assess its reliability and validity. METHODS: A primary questionnaire was developed with reference to existing instrument and information through discussion with experts, front-line professionals and patients living with HIV/AIDS. This questionnaire was applied in 443 patients living with HIV/AIDS. Some items were removed through the results of responsive rate, factor analysis, correlation matrix,internal consistency and so on. Reliability and validity were assessed after items reduction. RESULTS: The developed instrument contained 44 items, including 10 scales and other 3 items used for the evaluation of curative effect and side effect of anti-virus drug. No substantial ceiling/floor effects existed. All scales' internal consistency coefficients were > or = 0.70 and the whole instrument was 0.90. The two week retest reliability coefficient of the whole instrument was 0.80, and there were 6 scales below 0.70 of this coefficient. Multitrait/multiitem assessment indicated scaling success rates were all 100% for all items. Spearman correlation coefficient of total score of this instrument with SF-36 was 0.69. CONCLUSION: It was the first time that the developed QOL-CPLWHA instrument introducing the scale of hostility regarding mentality trend as well as expressed its acceptable reliability and validity so could be used for the evaluation of Chinese patients living with HIV/AIDS.