Parathyroidectomy for solitary parathyroid adenoma via trans-areola single site endoscopic approach: Results of a case-match study.

BACKGROUND: This study aimed to establish the standardized procedure of trans-areola single site endoscopic parathyroidectomy (TASSEP), and to compare the performance of TASSEP with that of conventional open parathyroidectomy (COP). METHODS: This study enrolled 40 patients with primary hyperparathyroidism (PHPT) who underwent TASSEP, and included 40 of 176 PHPT patients who underwent COP based on propensity score matching. The retrospective analysis was conducted based on prospectively collected data. Perioperative outcomes, including surgical profile, surgical burden and cosmetic results and follow-up were reported. The learning curve was described using a cumulative sum (CUSUM) analysis. RESULTS: 40 TASSEPs were completed successfully without conversions or severe complications. There was no statistically significant difference in operation time between TASSEP and COP groups (80.83 ± 11.95 vs. 76.95 ± 7.30 min, p = 0.084). Experience of 17 cases was necessitated to reach the learning curve of TASSEP. Postoperative pain score and traumatic index (C-reactive protein and erythrocyte sedimentation rate) in TASSEP were apparently lower than those in COP group (p < 0.05). During the proliferation and stabilization phases, TASSEP was associated with significantly better incision recovery and cosmetic scores. Postoperative serum calcium and PTH levels throughout the follow-up period indicated satisfactory surgical qualities in both groups. CONCLUSION: Based on precise preoperative localization and intraoperative planning facilitated by three-dimensional (3D) virtual modeling, TASSEP can be feasibly performed on selected patients with satisfactory success rates and low complication rates, providing preferable cosmetic results and alleviating the surgical burden to a certain extent.

The LiaSR Two-Component System Regulates Resistance to Chlorhexidine in Streptococcus mutans.

Chlorhexidine (CHX) is widely considered to be the gold standard for preventing dental caries. However, it is possible to induce resistance to CHX. The LiaSR two-component system has been identified that contributed to CHX resistance in Streptococcus mutans, which is one of the major pathogens in dental caries. However, the underlying mechanisms remain unclear. In this study, an MIC assay and a viability assessment demonstrated that after deleting the liaS and liaR genes, the sensitivity of mutants could increase. The Nile Red efflux assay exhibited that the efflux rates of mutants were significantly decreased. The RT-qPCR results indicated that the LiaSR two-component system-mediating influence on the expression of lmrB in S. mutans contributed to the efflux rate. The hydrophobicity assay and membrane potential assay showed that the mutants had higher levels of hydrophobicity and depolarization, suggesting that their membranes were more easily disturbed. The TEM graphs revealed that the border of the cell membrane was unclear in mutants compared with the wild-type strain, indicating that the cell envelope's stress response may have been inhibited. While the surface charge of mutants showed no significant difference in the wild-type strain according to the result of cytochrome c-based charged determination. This study provides valuable novel insights into the mechanisms of the LiaSR two-component system in the CHX resistance of S. mutans.

Correlation analysis of bone marrow microvessel density and miRNA expression on drug resistance in patients with chronic myelogenous leukemia after tyrosine kinase inhibitor treatment.

OBJECTIVE: This study analyzed the relationship between bone marrow microvessel density (MVD) and the expression of four miRNAs with chronic myelogenous leukemia (CML) resistance after tyrosine kinase inhibitor (TKI) treatment. METHODS: 234 CML patients were divided into resistance and non-resistance groups in terms of the results of the 5-year follow-up. Patients were divided into the Optimum response group and the Warning/Failure group based on TKI response. MVD was determined by immunohistochemistry, and the expression levels of four miRNAs (miR-106a, miR-155, miR-146a, and miR-340) in bone marrow biopsy specimens were examined by qPCR. We evaluated the association of MVD with four miRNAs and them predictive value for CML resistance after TKI treatment. RESULTS: The MVD and the levels of miR-106a, miR-155, and miR-146a were significantly higher while the miR-340 level was lower in the resistance group than the non-resistance group. Besides, MVD had a significant correlation with the levels of miR-340 and miR-155. According to the results of survival analysis, MVD as well as miR-340 and miR-155 levels were observably correlated with 5-year survival of patients without TKI resistance. The results of the ROC curve indicated that the MVD, miR-106a, miR-340, and miR-155 had good predictive accuracy for CML resistance after TKI treatment. As for the results of multivariate analysis, disease stage, risk level (high risk), high MVD, low miR-340 expression, and high miR-155 expression were all independent risk factors for CML resistance. CONCLUSION: MVD and the expression of miR-340 and miR-155 are closely associated with CML resistance after TKI treatment.

Nisin lantibiotic prevents NAFLD liver steatosis and mitochondrial oxidative stress following periodontal disease by abrogating oral, gut and liver dysbiosis.

Oral microbiome dysbiosis mediates chronic periodontal disease, gut microbial dysbiosis, and mucosal barrier disfunction that leads to steatohepatitis via the enterohepatic circulation. Improving this dysbiosis towards health may improve liver disease. Treatment with antibiotics and probiotics have been used to modulate the microbial, immunological, and clinical landscape of periodontal disease with some success. The aim of the present investigation was to evaluate the potential for nisin, an antimicrobial peptide produced by Lactococcus lactis, to counteract the periodontitis-associated gut dysbiosis and to modulate the glycolipid-metabolism and inflammation in the liver. Periodontal pathogens, namely Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia and Fusobacterium nucleatum, were administrated topically onto the oral cavity to establish polymicrobial periodontal disease in mice. In the context of disease, nisin treatment significantly shifted the microbiome towards a new composition, commensurate with health while preventing the harmful inflammation in the small intestine concomitant with decreased villi structural integrity, and heightened hepatic exposure to bacteria and lipid and malondialdehyde accumulation in the liver. Validation with RNA Seq analyses, confirmed the significant infection-related alteration of several genes involved in mitochondrial dysregulation, oxidative phosphorylation, and metal/iron binding and their restitution following nisin treatment. In support of these in vivo findings indicating that periodontopathogens induce gastrointestinal and liver distant organ lesions, human autopsy specimens demonstrated a correlation between tooth loss and severity of liver disease. Nisin's ability to shift the gut and liver microbiome towards a new state commensurate with health while mitigating enteritis, represents a novel approach to treating NAFLD-steatohepatitis-associated periodontal disease.

Multi-feature concatenation and multi-classifier stacking: An interpretable and generalizable machine learning method for MDD discrimination with rsfMRI.

Major depressive disorder (MDD) is a serious and heterogeneous psychiatric disorder that needs accurate diagnosis. Resting-state functional MRI (rsfMRI), which captures multiple perspectives on brain structure, function, and connectivity, is increasingly applied in the diagnosis and pathological research of MDD. Different machine learning algorithms are then developed to exploit the rich information in rsfMRI and discriminate MDD patients from normal controls. Despite recent advances reported, the MDD discrimination accuracy has room for further improvement. The generalizability and interpretability of the discrimination method are not sufficiently addressed either. Here, we propose a machine learning method (MFMC) for MDD discrimination by concatenating multiple features and stacking multiple classifiers. MFMC is tested on the REST-meta-MDD data set that contains 2428 subjects collected from 25 different sites. MFMC yields 96.9% MDD discrimination accuracy, demonstrating a significant improvement over existing methods. In addition, the generalizability of MFMC is validated by the good performance when the training and testing subjects are from independent sites. The use of XGBoost as the meta classifier allows us to probe the decision process of MFMC. We identify 13 feature values related to 9 brain regions including the posterior cingulate gyrus, superior frontal gyrus orbital part, and angular gyrus, which contribute most to the classification and also demonstrate significant differences at the group level. The use of these 13 feature values alone can reach 87% of MFMC's full performance when taking all feature values. These features may serve as clinically useful diagnostic and prognostic biomarkers for MDD in the future.

SEMA3B-AS1 suppresses colorectal carcinoma progression by inhibiting Semaphorin 3B-dependent VEGF signaling pathway activation.

Mounting evidence has demonstrated the considerable regulatory effects of long noncoding RNAs (lncRNAs) in the tumorigenesis and progression of various carcinomas. LncRNA Semaphorin 3B (SEMA3B) antisense RNA 1 (SEMA3B-AS1) has been found to be dysregulated in a few carcinomas recently. However, its potential function and mechanism in colorectal carcinoma (CRC) have not yet been examined. Here we show that SEMA3B-AS1 acts as a crucial regulator of CRC progression. We found that SEMA3B-AS1 expression was downregulated in CRC cell lines and tissues. Downregulation of SEMA3B-AS1 was significantly associated with poor survival in CRC patients. Overexpression of SEMA3B-AS1 reduced the cell growth and metastasis of CRC in vivo and in vitro. In addition, SEMA3B-AS1 promoted the expression of its sense-cognate gene SEMA3B, a member of the Semaphorin family (SEMAs), by recruiting EP300 to induce H3K9 acetylation at the SEMA3B promoter. Furthermore, we proved that SEMA3B-AS1 suppressed CRC angiogenesis by affecting the vascular endothelial growth factor signaling pathway activation which was regulated by the SEMA3B-NRP1 axis. Our work unravels a novel mechanism of SEMA3B-AS1 in the inhibition of CRC malignant progression and highlights its probability as a new promising diagnostic marker and therapeutic target for CRC interventions.

Bioinspired Gram-Scale Synthesis of Alstoscholarinoid B.

Herein, we describe a gram-scale synthesis of alstoscholarinoid B, a rearranged triterpenoid with potent antihyperuricemic bioactivity. This synthesis was inspired by the biogenetic hypothesis and achieved in seven steps from oleanolic acid with an overall yield of 51%.

Learning curve of trans-areola single-site endoscopic thyroidectomy in a high-volume center: A CUSUM-based assessment.

BACKGROUND: Limited attempts have been made in trans-areola single-site endoscopic thyroidectomy (TASSET) due to technical challenges and the lengthy time for proficiency. This study aimed to define the learning curve of TASSET and to describe improvements in operative performance over time. METHODS: Based on 222 consecutive TASSET procedures, the learning curve was established according to the operation time by using cumulative sum analysis (CUSUM). The end-point of learning curve was defined as the number of cases necessitated to reach the initial surgical proficiency stage. The demographic information, surgical and oncological outcomes, surgical stress, and postoperative complications were also analyzed. RESULTS: There were 70 cases of simple lobectomy for benign nodules and 152 cases of lobectomy with central neck dissection (CND) for malignancy. The mean operative time was 106.54 ± 38.07 min (range: 46-274 min). The learning curve identified two phases: the skill acquisition phase (Case 1-Case 41) and the proficiency phase (Case 42-Case 222). There were no significant differences in demographic information, drainage amount and duration, oncological outcomes, and postoperative complications between the two phases (p > 0.05). Both operation time and postoperative hospitalization decreased significantly in Phase 2 (154.63 ± 52.21 vs. 95.64 ± 22.96 min, p < 0.001; 4.12 ± 0.93 vs. 3.65 ± 0.63 days, p < 0.001). Additionally, the mean variations of surgical stress factors (C-reactive protein and erythrocyte sedimentation rate) decreased significantly as the phase progress. The case number required for proficiency phase in benign and malignant tumor were 18 and 33, respectively, and lymph node resection posed a significant impact on the endpoint of the learning curve (p < 0.001). Meanwhile, the size of nodule showed no significant impact (p = 0.622). For right-handed surgeons, 16 cases and 25 cases were required for technical competence in left-sided and right-sided lesions, respectively, and no significant difference reached (p = 0.266). CONCLUSIONS: TASSET has demonstrated safe and technically feasible with comparable oncological outcomes. Experience of 41 cases was required for surgical competence and proficiency. The initial learning stage could be more quickly adopted by high-volume thyroid surgeons with standardized procedures.

Heat-induced antigen retrieval utilizing modified Tris-EDTA buffer for reprobing of Western blots on nitrocellulose paper.

The development of heat-induced antigen retrieval technologies with Tris-EDTA buffer has dramatically improved immunostaining of specific antigens for routine immunohistochemical detection (Krenacs et al., 2010) [1]. However, little evidence exists on whether heat-Induced antigen retrieval utilizing Tris-EDTA buffer can strip western blot (WB) membranes and allow sequential reprobing. Here, we serendipitously discover that ∼95 °C Tris-EDTA buffer with 0.01% Tween 20 could repeatedly strip the Nitrocellulose membranes (NC). After electroblotting, NC blots were soaked into Tris-EDTA stripping buffer (∼95 °C, 10-25min) and we could perform at least five rounds (the following antibodies used: Vinculin, Atg7, Caspase-3, UBA5, JNK and ERK1/2) stripping in sequential chemiluminescent detections. The NC membranes also show clear western signals and background without losing transferred proteins during the reprobing process of WB. Hence, this study report additional new roles of the heat-Induced antigen retrieval Tris-EDTA buffer with 0.01% Tween 20. The method is simpler, more affordable and harmless for the nitrocellulose paper, which will be helpful for effective reprobing in western blotting applications.

Dlt operon regulates physiological function and cariogenic virulence in Streptococcus mutans.

Streptococcus mutans is one of the major cariogenic pathogens in the oral cavity. The dlt operon is responsible for the process of D-alanylation of lipoteichoic acid and is related to the virulence of S. mutans. The dlt operon contributes to the adhesion, biofilm formation, stress response, interspecies competitiveness and autolysis of S. mutans. In addition, we have summarized the possible regulatory networks of the dlt operon. This review highlights the significant role of the dlt operon in S. mutans and provides new ideas for ecological caries prevention.

What is this summary about? Dental caries is a common oral disease that destroys teeth. Streptococcus mutans is the major pathogen of dental caries and its cariogenic virulence factors depend on the ability of biofilm formation, acid production and tolerance, stress response, and interspecific competitiveness. The dlt operon is responsible for the process of D-alanylation of lipoteichoic acid and is related to the virulence of Gram-positive bacteria. To understand the role of the dlt operon in S. mutans, this review summarized this based on previous studies. What were the results? The dlt operon can regulate the D-alanylation of lipoteichoic acid to affect the cell surface charge of S. mutans. The change in characteristics of the cell wall will affect the physiological functions of S. mutans, such as adhesion, biofilm formation, stress response, autolysis and interspecies competitiveness. However, the regulatory mechanism of the dlt operon is still unclear and needs further study. What do the results of the study mean? This review highlights the significant role of the dlt operon in S. mutans, which will increase the understanding of the cariogenic mechanism of S. mutans and provide new ideas for ecological caries prevention, such as the development of antibacterial agents targeting the dlt operon.

Inactivation of horseradish peroxidase with crotonic acid for reprobing of western blotting.

Inactivation of horseradish peroxidase (HRP) treatment is a conventional preference to stripping for sequential detections of different proteins of chemiluminescent western blotting (WB). However, little evidence exists on whether other chemical substances treatment can affects the biological activity of HRP during stripping and re-probing of WB blots. Here, we successfully develop 20% crotonic acid (CA) as an alternative to stripping to inhibit HRP used for sequential chemiluminescent WB on polyvinylidene difluoride (PVDF) and Nitrocellulose (NC) membrane. Moreover, NC blots incubation in CA (40 °C, 30min) allow us to perform three round HRP inhibition in sequential detections without losing transferred proteins and damaging membrane. Hence, the method will help us save time and valuable samples without the need to rerun gels.

Breast cancer heterogeneity and its implication in personalized precision therapy.

Breast cancer heterogeneity determines cancer progression, treatment effects, and prognosis. However, the precise mechanism for this heterogeneity remains unknown owing to its complexity. Here, we summarize the origins of breast cancer heterogeneity and its influence on disease progression, recurrence, and therapeutic resistance. We review the possible mechanisms of heterogeneity and the research methods used to analyze it. We also highlight the importance of cell interactions for the origins of breast cancer heterogeneity, which can be further categorized into cooperative and competitive interactions. Finally, we provide new insights into precise individual treatments based on heterogeneity.

Single-gene knockout-coupled omics analysis identifies C9orf85 and CXorf38 as two uncharacterized human proteins associated with ZIP8 malfunction.

Human transmembrane protein metal cation symporter ZIP8 (SLC39A8) is a member of the solute carrier gene family responsible for intracellular transportation of essential micronutrients, including manganese, selenium, and zinc. Previously, we established a ZIP8-knockout (KO) human cell model using the CRISPR/Cas9 system and explored how the expression of ZIP8 could possibly contribute to a wide range of human diseases. To further assess the biophysiological role of ZIP8, in the current study, we employed isobaric tags for relative and absolute quantitation (iTRAQ) and detected the changes of the proteome in ZIP8-KO cells (proteomic data are available via ProteomeXchange with identifier PXD036680). A total of 286 differentially expressed proteins (206 downregulated and 80 upregulated proteins) were detected in the ZIP8-KO cell model, and subsequent bioinformatics analyses (GO, KEGG, KOG, and PPI) were performed on these proteins. Interestingly, four "uncharacterized" proteins (proteins with unknown biological function) were identified in the differentially expressed proteins: C1orf198, C9orf85, C17orf75, and CXorf38-all of which were under-expressed in the ZIP8-KO cells. Notably, C9orf85 and CXorf38 were amongst the top-10 most downregulated proteins, and their expressions could be selectively induced by essential micronutrients. Furthermore, clinical-based bioinformatic analysis indicated that positive correlations between the gene expressions of ZIP8 and C9orf85 or CXorf38 were observed in multiple cancer types. Overall, this study reveals the proteomic landscape of cells with impaired ZIP8 and uncovers the potential relationships between essential micronutrients and uncharacterized proteins C9orf85 and CXorf38. The differentially expressed proteins identified in ZIP8-KO cells could be the potential targets for diagnosing and/or treating human ZIP8-associated diseases, including but not limited to malnutrition, viral infection, and cancers.

Editorial: Apatinib and Anlotinib in the Treatment of Radioactive Iodine Refractory and Highly Invasive Thyroid Carcinoma.

Thyroid cancer (TC) is the most prevalent endocrine malignancy, with a rising incidence in the past decade [...].

Effects of cold atmospheric plasma treatment on resin bonding to high-translucency zirconia ceramics.

This study aims to evaluate the effects of cold atmospheric plasma (CAP) treatment on the bonding of resin cement to high-translucency zirconia. Zirconia specimens were subjected to different treatments: no treatment (ZrT), 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primer (ZrT-M), alumina particle air-abrasion with/without MDP-containing primer (ZrT-AM/ZrT-A), CAP with/without MDP-containing primer (ZrT-PM/ZrT-P). The surface topography, wettability, and chemical composition were evaluated. The shear bond strength (SBS) was tested before and after thermocycling. CAP did not alter the morphology, increased the wettability, and decreased the carbon/oxygen ratio of zirconia surface. The SBSs of ZrT-PM and ZrT-P were significantly higher than the other groups. After thermocycling, ZrT-A, ZrT-M, ZrT-AM, and ZrT-P showed comparable SBSs, all of which were lower than ZrT-PM. It was concluded that CAP improved the bonding performance of high-translucency zirconia without damaging its surface. The combination of CAP with MDP further enhanced the bond strength and may enable durable bonding.

The Experience Among College Students with Social Anxiety Disorder in Social Situations: A Qualitative Study.

Background: Few individuals have focused on the experience of students during social events, especially among college students with social anxiety disorder. This study aimed to explore the anxiety experience among college students with social anxiety disorder in social situations. Methods: This qualitative interpretive study was conducted on college students who were diagnosed with social anxiety disorder (SAD) and recruited from two colleges in Heilongjiang Province, China. A total of 7 participants were selected by purposive sampling with maximum variability. Data were collected through semistructured individual interviews, and data analysis was performed by using Colaizzi's 7-step analysis method. Results: The findings from the analysis of the interviews were classified into 4 themes and several main categories, including distorted self-awareness (3 main categories), fear of negative reaction from others (2 main categories), adverse reaction of body and mind (4 main categories) and strong desire to seek treatment. Conclusion: In our study, we sought to understand the anxiety experience among college students with social anxiety disorder in social situations. The study results provide a reference for psychologists and clinical medical staff and establish a scientific basis for the prevention and intervention of social anxiety disorder.

The effect of omega-3 polyunsaturated fatty acids on stroke treatment and prevention: a systematic review and meta-analysis.

Introduction: Background: in recent years, n-3 PUFAs have been confirmed to be associated with cardiovascular and cerebrovascular diseases, but the link between n-3 PUFAs and stroke remains controversial. Objective: this study aimed to evaluate the association between n-3 PUFAs and stroke. Methods: we performed a comprehensive search of the following electronic databases: PubMed, Embase, Cochrane Library, Web of Science and CNKI. Literature screening and quality assessment were performed according to inclusion and exclusion criteria. Cochrane's tool was used to assess the methodological components of each study, and the Stata 15.1 software was used to perform the meta-analysis. Results: a total of 18 RCTs were included, and the meta-analysis showed no differences in vascular disease-related death between the n-3 PUFA and control groups (RR, 0.95, 95 % CI: 0.89 to 1.01, p = 0.114 > 0.05). However, there was a significant difference in the lower n-3 PUFA dose subgroup (RR, 0.93, 95 % CI: 0.87 to 0.99, p = 0.034 < 0.05). Oral administration of n-3 PUFAs did not significantly reduce the risk of the following cerebrovascular accidents: stroke (RR = 1.00, 95 % CI: 0.93 to 1.07, p = 0.983 > 0.05), ischemic stroke (RR = 0.99, 95 % CI: 0.896 to 1.094, p = 0.841 > 0.05), hemorrhagic stroke (RR = 1.249, 95 % CI: 0.939 to 1.662, p = 0.127 > 0.05) and TIA (RR = 1.016, 95 % CI: 0.882 to 1.170, p = 0.824 > 0.05). The levels of TC (SMD, -0.167, 95 % CI: -0.193 to -0.141, p = 0 < 0.05) and TG (SMD, -0.065, 95 % CI: -0.087 to -0.042, p = 0 < 0.05) in the n-3 PUFA group were significantly decreased, but no significant improvement in the LDL (SMD, 0.022, 95 % CI: 0.005 to 0.040, p = 0.889 > 0.05) and HDL (SMD, 0.008, 95 % CI: -0.009 to 0.025, p = 0.368 > 0.05) levels was observed. Conclusion: this systematic review and meta-analysis suggests that treatment with low-dose n-3 PUFAs can reduce cerebrovascular disease-related death. After the oral administration of n-3 PUFAs, the levels of TC and TG decreased significantly, but n-3 PUFAs did not prevent the occurrence of cerebrovascular accidents or improve LDL or HDL levels.

Introducción: Antecedentes: en los últimos años se ha confirmado que los AGPI n-3 se relacionan con las enfermedades cardiovasculares y cerebrovasculares, pero el vínculo entre los AGPI n-3 y el ictus sigue siendo objeto de controversia. Objetivo: este estudio se propuso evaluar la relación entre AGPI n-3 e ictus. Métodos: se realizaron búsquedas en las siguientes bases de datos electrónicas: PubMed, Embase, Cochrane Library, Web of Science y CNKI. Se utilizó la herramienta de Cochrane para evaluar los componentes metodológicos de cada estudio y el software Stata para el metanálisis. Resutados: se incluyeron 18 ECA y el metanálisis no mostró diferencias en cuanto a la muerte relacionada con enfermedades vasculares entre los grupos de AGPI n-3 y de control (RR: 0,95, IC del 95 %: 0,89 a 1,01). Sin embargo, hubo una diferencia significativa en el subgrupo de dosis más baja de AGPI n-3 (RR: 0,93, IC del 95 %: 0,87 a 0,99). La administración oral de AGPI n-3 no redujo significativamente el riesgo de los siguientes accidentes cerebrovasculares: ictus (RR = 1,00, IC 95 %: 0,93 a 1,07), ictus isquémico (RR = 0,99, IC 95 %: 0,896 a 1. 094), ictus hemorrágico (RR = 1,249, IC 95 %: 0,939 a 1,662) y AIT (RR = 1,016, IC 95 %: 0,882 a 1,170). Los niveles de TC (DME: -0,167, IC del 95 %: -0,193 a 0,141) y TG (DME -0,065, IC del 95 %: -0,087 a -0,042) en el grupo de AGPI n-3 se redujeron significativamente, pero no hubo una mejora significativa en los niveles de LDL (SMD: 0,022, IC 95 %: 0,005 a 0,040) y HDL (SMD: 0,008, IC 95 %: -0,009 a 0,025). Conclusiones: esta revisión sistemática y metaanálisis sugiere que el tratamiento con PUFA n-3 en dosis bajas puede reducir la muerte relacionada con la enfermedad cerebrovascular. Después de la administración oral de PUFA n-3, los niveles de TC y TG disminuyeron significativamente, pero los PUFA n-3 no impidieron la aparición de accidentes cerebrovasculares ni mejoraron los niveles de LDL o HDL.

D-alanylation of lipoteichoic acid contributes to biofilm formation and acidogenesis capacity of Streptococcusmutans.

BACKGROUND: D-alanylation of Lipoteichoic acid (LTA) is considered to be essential for virulence factors expression in Gram-positive microorganism. The effects of the D-alanylation of LTA on biofilm formation and acidogenesis of Streptococcus mutans (S. mutans) are still not clearly understood. AIM: This study was designed to investigate the impact of D-alanylation of LTA on biofilm formation and acidogenesis of S. mutans and explore the related mechanisms. METHODS AND MATERIAL: We compared the biofilm formation process by fluorescence microscope observation of LTA D-alanylation blocking strain with that of the wildtype strain. Auto-aggregation, cell surface charge, and polysaccharide production assays were performed to investigate the related mechanisms. pH drop assay and glycolysis pH drop-down analysis were carried out to evaluate the acidogenesis capacity of S. mutans after LTA D-alanylation blocking. To identify the biofilm formation and adhesive-related genes expressions of S. mutans mutant, qRT-PCR was performed. RESULTS: After blocking off the D-alanylation of LTA, S. mutans could not form the three-dimensional structural biofilm, in which cells were scattered on the substratum as small clusters. The auto-aggregation was prompted due to the mutant strain cell morphology change (*p < 0.05). Furthermore, more negative charges were found on the mutant strain cells surfaces and fewer water-insoluble glucans were produced in mutant biofilm (*p < 0.05). The adhesion capacity of the S. mutans biofilm was impaired after LTA D-alanylation blocking (*p < 0.05). Biofilm formation and adhesive-related genes expressions decreased (*p < 0.05), especially at the early stages of biofilm formation. S. mutans mutant strains exhibited suppressed acidogenesis because its glycolytic activity was impaired. CONCLUSION: The results of this study suggest that blocking of LTA D-alanylation disrupts normal biofilm formation in S. mutans predominantly if not entirely by altering intercellular auto-aggregation, cell adhesion, and extracellular matrix formation. Moreover, our study results suggest that the LTA D-alanylation plays an important role in S. mutans acidogenesis by altering glycolytic activity. These findings add to the knowledge about mechanisms underlying biofilm formation and acid tolerance in S. mutans.

A Novel Mitochondrial-Related Gene Signature for the Tumor Immune Microenvironment Evaluation and Prognosis Prediction in Lung Adenocarcinoma.

Lung adenocarcinoma (LUAD) remains the most common deadly disease and has a poor prognosis. More and more studies have reported that mitochondrial-related genes (MTRGs) were associated with the clinical outcomes of multiple tumors solely. In this study, we aimed to develop a novel prognostic model based on MTRGs. Differentially expressed MTRGs were identified from TCGA-LUAD and GSE31210 cohorts. Univariate Cox regression analysis was utilized to screen differentially expressed MTRGs that were related to prognosis of LUAD. Then, LASSO Cox regression analysis was used to develop a prognostic signature. ESTIMATE was used for estimating the fractions of immune cell types. In this study, we identified 44 overlapping differentially expressed MTRGs in TCGA-LUAD and GSE31210 cohorts. Among 44 overlapping differentially expressed MTRGs, nine genes were associated with prognosis of LUAD. When the penalty parameter lambda was the minimum, there were six genes meeting the conditions of constructing the signature, including SERPINB5, CCNB1, FGR MAOB, SH3BP5, and CYP24A1. The survival analysis suggested that prognosis of patients in the high-risk group was significantly worse than that in the low-risk group. Cox regression analyses showed that the risk score was an independent predictor of LUAD prognosis. As with the results of ESTIMATE score, the degree of immune cell infiltration in the low-risk group was higher than that in the high-risk group, such as TIL, Treg, and B cells. In addition, TMB and cancer stem cell infiltration were higher in the low-risk group than the high-risk group. In conclusion, we developed a novel MTRG signature acting as a negative independent prognostic factor. In the future, individualized treatments and medical decision-making may benefit from using the predicted model.