The Effect of Bovine Trypsin on the Adhesion and pH of Dental Plaque Biofilms: An In Vitro Study.

OBJECTIVE: The aim of this study was to investigate the effect of bovine trypsin on the adhesion and pH of dental plaque biofilms. METHODS: A multispecies dental plaque biofilm model and a single-species dental plaque biofilm model were established in vitro. Three groups were tested: (1) blank control group (aseptic ultrapure water); (2) negative control group (1M Tris-HCl buffer, pH = 7.4); and (3) experimental group (bovine trypsin). Adhesion ability was measured using an automatic microplate reader and visualised by confocal laser scanning microscopy (CLSM). The pH was measured using a pH meter. The expression of gtfB, gtfC, and gtfD was analysed using quantitative real-time polymerase chain reaction. RESULTS: Adhesion ability in the experimental group was significantly lower than that in the blank group and the negative control group (P < .05); readhesion ability in the experimental group was inhibited for a certain period of time (24-hour multispecies biofilms were inhibited from 4 to 8 hours, and the 48- and 72-hour multispecies biofilms were inhibited from 2 to 6 hours; P < .05). The decrease in pH was inhibited for a certain period of time (24-hour multispecies biofilms were inhibited from 2 to 8 hours, and the 48- and 72-hour multispecies biofilms were inhibited from 1 to 8 hours; P < .05). Expression levels of gtfB, gtfC, gtfD, and ldh in the experimental group were significantly lower than those in the blank group (P < .05). CONCLUSIONS: Bacterial adhesion, and readhesion, decreasd pH, and expression of adhesion- and acid-related genes by Streptococcus mutans in biofilms could be reduced by bovine trypsin for a certain period of time.

The effect of bovine trypsin on dental biofilm dispersion: an in vitro study.

To investigate the degradation effect of bovine trypsin on multispecies biofilm of caries-related bacteria and provide an experimental foundation for the prevention of dental caries. Standard strains of S. mutans, S. sanguis, S. gordonii, and L. acidophilus were co-cultured to form 24 h, 48 h, and 72 h biofilms. The experimental groups were treated with bovine trypsin for 30 s, 1 min, and 3 min. Morphological observation and quantitative analysis of extracellular polymeric substances (EPS), live bacteria, and dead bacteria were conducted using the confocal laser scanning microscope (CLSM). The morphological changes of EPS and bacteria were also observed using a scanning electron microscope (SEM). When biofilm was treated for 1 min, the minimal inhibitory concentration (MIC) of bovine trypsin to reduce EPS was 0.5 mg/mL in 24 h and 48 h biofilms, and the MIC of bovine trypsin was 2.5 mg/mL in 72 h biofilms (P < 0.05). When biofilm was treated for 3 min, the MIC of bovine trypsin to reduce EPS was 0.25 mg/mL in 24 h and 48 h biofilms, the MIC of bovine trypsin was 1 mg/mL in 72 h biofilm (P < 0.05). The ratio of live-to-dead bacteria in the treatment group was significantly lower than blank group in 24 h, 48 h, and 72 h multispecies biofilms (P < 0.05). Bovine trypsin can destroy multispecies biofilm structure, disperse biofilm and bacteria flora, and reduce the EPS and bacterial biomass in vitro, which are positively correlated with the application time and concentration.

An in vitro study on the degradation of multispecies biofilm of periodontitis-related microorganisms by bovine trypsin.

To investigate the degradation effect of bovine trypsin on multispecies biofilm of periodontitis-related bacteria and to provide an experimental reference for exploring new methods for controlling biofilms of periodontitis-related microorganisms, the multispecies biofilm of periodontitis-related microorganisms was established. Standard strains of Porphyromonas gingivalis, Fusobacterium nucleatum subsp. polymorpha, Actinomyces viscosus, and Aggregatibacter actinomycetemcomitans were co-cultured to form the biofilm. The experimental groups were treated with bovine trypsin, distilled water was applied as the blank control group, and phosphate saline buffer (pH = 7.4) as the negative control group. Morphological observation and quantitative analysis of extracellular polymeric substances (EPS), live bacteria, and dead bacteria were conducted using a laser confocal microscope. The morphological changes of EPS and bacteria were also observed using a scanning electron microscope. The results of morphological observations of modeling were as follows. EPS aggregated as agglomerates, and bacteria flora were wrapped by them, showing a three-dimensional network structure, and channel-like structures were inside the biofilm. Live bacteria were distributed on the surface of the EPS or embedded in them, dead bacteria aggregated between live flora and the bottom layer of biofilms. After being treated with bovine trypsin, the three-dimensional network structure and the channel-like structure disappeared, and the EPS and live and dead bacteria decreased. Quantitative analysis results are as follows. When biofilm was treated for 30 s, 1 min, and 3 min, the minimum effective concentrations of bovine trypsin to reduce EPS were 2 mg/ml (P < 0.05), 0.5 mg/ml (P < 0.05), and 0.25 mg/ml (P < 0.05), respectively. The minimum effective concentrations of bovine trypsin to reduce the live or dead bacteria were 2 mg/ml (P < 0.05), 0.5 mg/ml (P < 0.05), and 0.5 mg/ml (P < 0.05), respectively. There was no significant difference in the ratio of live/dead bacteria after the biofilm was treated for 30 s with bovine trypsin at the concentration of 0.25, 0.5, 1, and 2 mg/ml (P > 0.05), and the minimum effective concentration to reduce the ratio of live bacteria/dead bacteria was 0.25 mg/ml (P < 0.05) after treatment for 1 min and 3 min. Therefore, bovine trypsin can destroy biofilm structure, disperse biofilm and bacteria flora, and reduce the EPS and bacterial biomass, which are positively correlated with the application time and concentration.

Comparison of Diagnostic Efficacy of [68Ga]Ga-FAPI-04 and [18F]FDG PET/CT for Staging and Restaging of Gastric Cancer.

Purpose: This study aimed to compare the potential diagnostic efficacy of gallium68-fibroblast-activation protein inhibitor ([68Ga]Ga-FAPI-04) and fluorine18-fluorodeoxyglucose ([18F]-FDG) positron emission tomography-computed tomography (PET/CT) for primary tumors, lymph nodes, and distant metastatic lesions of gastric cancer (GC), and to explore the effects of [68Ga]Ga-FAPI-04 and [18F]-FDG on tumor staging and restaging in GC. Methods: This single-center retrospective study (NCT2100044131) was conducted at the Affiliated Hospital of the Southwest Medical University between June 2020 and December 2021. Images of patients with GC who were pathologically confirmed and underwent contemporaneous [18F]-FDG and [68Ga]Ga-FAPI-04 PET/CT within 1 week were analyzed. The diagnostic efficacy of [68Ga]Ga-FAPI-04 PET/CT and [18F]-FDG PET/CT for TNM staging of GC was compared using McNemar test. The maximum standard uptake value (SUVmax) of each lesion in the two imaging types was compared using the Mann-Whitney U test. Results: In total, 25 patients with GC (mean age, 56 ± 12 years) were evaluated. [68Ga]Ga-FAPI-04 PET/CT exhibited higher sensitivity compared to [18F]-FDG PET/CT for detecting primary tumors (18/19 [94.74%] vs. 13/19 [68.42%], χ2 = 6.866, P < 0.01), lymph node metastasis (75/77 [97.40%] vs. 32/77 [41.56%], χ2 = 2.888, P =0.089), and distant metastases (275/283 [97.17%] vs. 122/283 [43.11%], χ2 = 11.858, P < 0.01). [68Ga]Ga-FAPI-04 accumulation was significantly higher than that of [18F]FDG in tumors (median SUVmax, 10.28 vs 3.20; U=59.00, P < 0.01), lymph node metastasis metastases (median SUVmax, 9.20 vs 3.15; U=53.50, P < 0.01), and distant metastases (median SUVmax, 8.00 vs 4.20; U=200.00, P < 0.01). Compared to [18F]-FDG PET/CT, [68Ga]Ga-FAPI-04 PET/CT resulted in new oncological findings in 14/25 patients and corrected tumor staging or restaging in 7/25 patients. Conclusion: Our preliminary results regarding the impact of [68Ga]Ga-FAPI-04 PET/CT on tumor staging highlight the potential of this approach for increasing the accuracy of GC diagnosis, which may facilitate treatment decision-making.

Relationship between rosacea and dietary factors: A multicenter retrospective case-control survey.

Although patients with rosacea often consult dermatologists for dietary factors that might be related to their skin disorders, few studies have been conducted to research the relationship between rosacea and dietary factors. The purpose of this study was to evaluate the potential relationship between rosacea and diet among the large Chinese population with rosacea, which would provide dietary guidelines for patients with rosacea. A multicenter case-control study was conducted. The feeding frequency 2 years before the occurrence of rosacea was collected by standardized questionnaires. Multiple logistic regression analysis was used to calculate risks related to the diet. One thousand three hundred and forty-seven patients with rosacea and 1290 controls were enrolled in our study. We found that high-frequency intake of fatty food and tea presented a positive correlation with rosacea, while high-frequency dairy product intake showed significant negative correlation with rosacea. Sweet food, coffee and spicy food appeared to be independent of any subset of rosacea in our study. However, high-frequency dairy product intake showed a borderline beneficial effect on rosacea severity. We further analyzed the correlation between diet and the subtype of rosacea. We found that high-frequency fatty intake was associated with erythematotelangiectatic rosacea (ETR) and phymatous rosacea, while high-frequency tea intake was only associated with ETR. In addition, high-frequency dairy product intake showed negative correlations with ETR and papulopustular rosacea. Rosacea is associated with some dietary factors, and our study is valuable in establishing dietary guidelines to prevent and improve rosacea.

Further studies about Coactosin-like protein-1 affecting the migration of mouse neocortical neurons.

During the development of mammalian cortex, late neurons generated by neuronal progenitors bypass earlier-born neurons and migrate to reach upper layers of cortical plate in an inner-to-outer fashion. Filamentous-actin (F-actin) can regulate neuronal migration, whereas Coactosin-like protein 1 (Cotl1) modulates F-actin. Lys 75 and Arg 73 of Cotl1 play an important role in binding F-actin; when they are mutated to Glu, Cotl1 cannot bind F-actin, called as a non-actin-binding mutant (ABM). The Lys 131 site of Cotl1, the 5-Lipoxygenase (5LO) binding site, is spatially close to Lys 75, leading to impact the binding of Cotl1 to F-actin. When Lys 131 is mutated to Ala (K131A), Cotl1 cannot bind to 5LO. We have demonstrated that overexpression of Cotl1 inhibited neuronal migration and increased the length of neuronal leading processes. To further explore cellular and molecular mechanisms of Cotl1's effect on neuronal migration, we constructed two mutant vectors-Cotl1-ABM and Cotl1-K131A and studied using in utero electroporation and primary neuronal culture technique. Results indicated that in the Cotl1-ABM group, the neuronal migration and length of the leading process both recovered as control neurons at the postnatal day 1 (P1), while in the Cotl1-K131A group, numerous neurons remained in deeper layers of cortical plate or intermediate zone. However, at P7, most Cotl1-K131A transfected neurons reached their destination. Moreover, we found that overexpression of Cotl1 inhibited the proliferation and mitotic activity of NPs. Therefore, These results demonstrated that Cotl1 played an important role in mouse neocortical development.