T-cell infiltration and its regulatory mechanisms in cancers: insights at single-cell resolution.

Tumor-infiltrating T cells recognize, attack, and clear tumor cells, playing a central role in antitumor immune response. However, certain immune cells can impair this response and help tumor immune escape. Therefore, exploring the factors that influence T-cell infiltration is crucial to understand tumor immunity and improve therapeutic effect of cancer immunotherapy. The use of single-cell RNA sequencing (scRNA-seq) allows the high-resolution analysis of the precise composition of immune cells with different phenotypes and other microenvironmental factors, including non-immune stromal cells and the related molecules in the tumor microenvironment of various cancer types. In this review, we summarized the research progress on T-cell infiltration and the crosstalk of other stromal cells and cytokines during T-cell infiltration using scRNA-seq to provide insights into the mechanisms regulating T-cell infiltration and contribute new perspectives on tumor immunotherapy.

Correlation between periodontitis and prostate-specific antigen levels in the elderly Chinese male population.

BACKGROUND: The comparison of prostate-specific antigen (PSA) levels among older individuals with different periodontal statuses has not been fully investigated. Here we aimed to explore the correlation between the staging and grading of periodontitis and PSA levels in an elderly Chinese male population, which may lead to a biopsy recommendation and prevent prostate cancer as early as possible. METHODS: The study included 996 individuals aged ≥ 55 years who participated in routine postretirement physical examinations. Periodontal data included probing depth and gingival recession on four sites/tooth and on two diagonal quadrants (1-3 or 2-4) while excluding third molars, and clinical attachment loss was calculated. Periodontal status was classified as none, mild-moderate or severe periodontitis according to the Centers for Disease Control and Prevention and the American Academy of Periodontology case definition. Blood samples, oral health status and sociodemographic characteristics were collected by using general and oral examinations and questionnaires. Linear and logistic regressions were used to estimate the correlation between periodontitis severity and PSA levels, respectively. RESULTS: A total of 479 men had mild-moderate periodontitis and 355 had severe periodontitis; 162 men were periodontally healthy individuals. After adjusting for potential confounders, PSA levels were significantly lower in the individuals without periodontitis than in those with mild-moderate (P = 0.04) or severe (P = 0.03) periodontitis. However, PSA levels did not significantly correlate with periodontitis severity (P = 0.06). Although the ORs of elevated PSA were not significant, individuals with PSA ≥ 4.0 ng/mL were more likely to have periodontitis. CONCLUSIONS: In a sample of an elderly Chinese male population, after adjusting for possible confounders, serum PSA levels in individuals with periodontitis were significantly higher than those in individuals without periodontitis, but serum PSA did not significantly correlate with periodontitis severity.

Comparison of Positioning Accuracy Between 2 Different Implant Systems Using Mucosa-Supported Surgical Templates: A Retrospective Clinical Study.

Although guided implant surgery is widely practiced, clinical studies examining the differences in accuracy between implanting systems that use the same surgical guide are currently lacking. This study aimed to evaluate and compare the effects of different dental implanting systems on positioning accuracy using a uniform type of stereolithographic surgical guide to account for cumulative errors in guide production. One hundred BEGO Semados S implants (group A) and 91 NobelActive implants (group B) were inserted into patients using the same type of guide. The accuracy was assessed by matching the preoperative and postoperative cone-beam computerized tomography. The implant shoulder, tip, depth, and angular deviation were registered. Statistically significant differences between groups were determined using Student t test, bivariate correlation test, and generalized estimating equation. The angular deviation was 3.16 ± 1.74° in group A and 2.58 ± 1.41° in group B (P = .013); the depth deviation was 0.44 ± 0.23 mm in group A and 0.51 ± 0.22 mm in group B (P = .032). In terms of vertical accuracy, the Bego implant system is superior to the Nobel implant system using the same type of surgical guide, while the angle accuracy is opposite. Therefore, it is important to control the depth when using the template-guided surgery with the Nobel implant system. Similarly, angle control should be emphasized in the Bego implant system. Measurements of the deviations provide the basis for a clinical reference that will be useful in preoperative analysis for improving the safety and accuracy of guided implant surgical procedures.

Chitosan/hydroxyapatite composite coatings on porous Ti6Al4V titanium implants: in vitro and in vivo studies.

PURPOSE: Titanium implants are widely used in the treatment of dentition defects; however, due to problems such as osseointegration failure, peri-implant bone resorption, and peri-implant inflammation, their application is subject to certain restrictions. The surface modification of titanium implants can improve the implant success rate and meet the needs of clinical applications. The goal of this study was to evaluate the effect of the use of porous titanium with a chitosan/hydroxyapatite coating on osseointegration. METHODS: Titanium implants with a dense core and a porous outer structure were prepared using a computer-aided design model and selective laser sintering technology, with a fabricated chitosan/hydroxyapatite composite coating on their surfaces. In vivo and in vitro experiments were used to assess osteogenesis. RESULTS: The quasi-elastic gradient and compressive strength of porous titanium implants were observed to decrease as the porosity increased. The in vitro experiments demonstrated that, the porous titanium implants had no biological toxicity; additionally, the porous structure was shown to be superior to dense titanium with regard to facilitating the adhesion and proliferation of osteoblast-like MC3T3-E1 cells. The in vivo experimental results also showed that the porous structure was beneficial, as bone tissue could grow into the pores, thereby exhibiting good osseointegration. CONCLUSIONS: Porous titanium with a chitosan/hydroxyapatite coating promoted MC3T3-E1 cell proliferation and differentiation, and also improved osseointegration in vitro. This study has meaningful implications for research into ways of improving the surface structures of implants and promoting implant osseointegration.

[Selective laser sintering and performances of porous titanium implants].

OBJECTIVE: This work aims to analyze the mechanical properties and biocompatibility of porous titanium (Ti) implants fabricated by selective laser sintering (SLS) and investigate the promotion of osseointegration by porous titanium implant combined with chitosan (CS)/hydroxyapatite(HA) composite coating. METHODS: Ti6Al4V specimens were prepared, and CS/HA composite coating was fabricated on the surface of a portion of the specimens. The mechanical properties of the samples were observed by scanning electron microscope. MC3T3-E1 cells were cultured in vitro, and their biological properties in vitro were analyzed using live and dead viability cell staining method, methyl thiazolyl tetrazolium (MTT) staining, and alkaline phosphatase (ALP) level detection. The thread implant specimens were implanted in the femoral condyle of rabbits, and biological performance was evaluated in vivo. RESULTS: Quasi-elastic gradient of porous specimens decreased with increasing porosity, and the quasi-elastic gradient were close to cortical and cancellous bone when the porosities were 30% and 70%. The specimens showed good biocompatibility. Combined with CS/HA coating, the implants promoted the proliferation and differentiation of MC3T3-E1 cells and facilitated the entry of bone tissue into pores and good osteogenesis. CONCLUSIONS: The porous titanium implant exhibited favorable mechanical properties and biocompatibility. Combined with CS/HA coating, the implant exhibited bone inducibility, which leads to stable osteogenesis.

Influence of inner circular sealing area impression method on the retention of complete dentures.

The aims of the present study were to describe an impression method of "inner circular sealing area" and to evaluate the effect of the method on retention, aesthetics and comfort of complete dentures, which lack labial base for patients with maxillary protrusions. Three patients were subjected to the experiment, and two sets of complete maxillary dentures were made for each patient; the first set was made without labial base via an inner circular sealing area method (experimental group) and the second had an intact base that was made with conventional methods (control group). Retention force tests were implemented with a tensile strength assessment device to assess the retention and a visual analogue scale (VAS) was used to evaluate the comfort between the two groups. Results showed larger retention force, better aesthetics and more comfort in the experimental group. The improved two-step impression method formed an inner circular sealing area that prevented damage to the peripheral border seal effect of the denture caused by incomplete bases and obtained better denture retention.

Influence of Inner Circular Sealing Area Impression Method on the Retention of Complete Dentures

The aims of the present study were to describe an impression method of "inner circular sealing area" and to evaluate the effect of the method on retention, aesthetics and comfort of complete dentures, which lack labial base for patients with maxillary protrusions. Three patients were subjected to the experiment, and two sets of complete maxillary dentures were made for each patient; the first set was made without labial base via an inner circular sealing area method (experimental group) and the second had an intact base that was made with conventional methods (control group). Retention force tests were implemented with a tensile strength assessment device to assess the retention and a visual analogue scale (VAS) was used to evaluate the comfort between the two groups. Results showed larger retention force, better aesthetics and more comfort in the experimental group. The improved two-step impression method formed an inner circular sealing area that prevented damage to the peripheral border seal effect of the denture caused by incomplete bases and obtained better denture retention.

O objetivo deste caso foi descrever um método de impressão por "área de selamento circular interno" e avaliar o efeito deste método na retenção, estética e conforto de próteses totais sem base labial para pacientes com protrusão maxilar. Três pacientes foram objeto desta experiência e foram feitas duas próteses maxilares completas para cada um deles; a primeira foi elaborada sem base labial pelo método de área de selamento circular interno (grupo experimental) e a outra teve uma base feita pelo método convencional (grupo controle). Foram realizados testes de retenção com estudo de tensão para avaliar a retenção e para avaliação do conforto dos dois grupos, foi empregada a escala analógica visual (EAV). Os resultados demonstraram que o grupo experimental apresentou força de retenção maior, estética melhor e mais conforto. O método modificado de impressão em duas etapas formou uma área de selamento circular interno que evitou danos ao selamento periférico causados por bases incompletas e obteve melhor retenção da prótese.