Epidemiological and clinical characteristics of psittacosis among cases with complicated or atypical pulmonary infection using metagenomic next-generation sequencing: a multi-center observational study in China.

BACKGROUND: Chlamydia psittaci (C. psittaci) causes parrot fever in humans. Development of metagenomic next-generation sequencing (mNGS) enables the identification of C. psittaci. METHODS: This study aimed to determine the epidemiological and clinical characteristics of parrot fever cases in China. A multi-center observational study was conducted in 44 tertiary and secondary hospitals across 14 provinces and municipalities between April 2019 and October 2021. RESULTS: A total of 4545 patients with complicated or atypical pulmonary infection were included in the study, among which the prevalence of C. psittaci was determined to be 2.1% using mNGS. The prevalence of C. psittaci was further determined across demographic groups and types of specimens. It was significantly higher in patients with senior age (2.6% in those > 50 years), winter-spring (3.6%; particularly in December, January, and February), and southwestern (3.4%) and central and southern China (2.7%) (each P < 0.001). Moreover, the prevalence was the highest in bronchoalveolar lavage fluid (BALF) (2.9%), compared with sputum (1.1%) and peripheral blood specimens (0.9%). Additionally, co-infection of principal microorganisms was compared. Certain microorganisms were more likely to co-infect in parrot fever cases, such as Candida albicans in BALF (26.7%) and peripheral blood (6.3%), compared with non-parrot fever cases (19.7% and 1.3%); however, they did not significantly differ (each P > 0.05). CONCLUSION: Parrot fever remains low in patients with complicated or atypical pulmonary infection. It is likely to occur in winter-spring and southwestern region in China. BALF may be the optimal specimen in the application of mNGS. Co-infection of multiple microorganisms should be further considered.

Dual function of quercetin as an MMP inhibitor and crosslinker in preventing dentin erosion and abrasion: An in situ/in vivo study.

OBJECTIVE: The aim of the present study was to evaluate the in situ/in vivo effect of quercetin on dentin erosion and abrasion. METHODS: Human dentin blocks (2 × 2 × 2 mm) were embedded and assigned to 6 groups: 75 µg/mL, 150 µg/mL and 300 µg/mL quercetin (Q75, Q150, Q300); 120 µg/mL chlorhexidine (CHX, positive control); and deionized water and ethanol (the negative controls). The specimens were treated with the respective solutions for 2 min and then subjected to in situ/in vivo erosive/abrasive challenge for 7 d as follows: in vivo erosion 4 times a day and then in vivo toothbrush abrasion after the first and last erosive challenges of each day. Dentin loss was assessed by profilometry. An additional dentin specimen was used to evaluate the penetration depth of quercetin into dentin by tracking the spatial distribution of its characteristic Raman peak. Moreover, dentin blocks (7 × 1.7 × 0.7 mm) were used to detect the impact of quercetin on dentin-derived matrix metalloproteinase (MMP) inhibition by in situ zymography, and the inhibition percentage (%) was calculated. Additionally, the potential collagen crosslinking interactions with quercetin were detected by Raman spectroscopy, and the crosslinking degree was determined with a ninhydrin assay. Fully demineralized dentin beams (0.5 × 0.5 × 10 mm) were used to evaluate the impact of quercetin on the mechanical properties of dentin collagen fibre by the ultimate micro-tensile strength test (µUTS). The data were analysed by one-way analysis of variance and Tukey's test (α = 0.05). RESULTS: Compared to the negative controls, all treatment solutions significantly reduced dentin loss. The dentin loss of Q150 and Q300 was significantly less than that of CHX (all P < 0.05). The amount of quercetin decreased with increasing dentin depth, and the maximum penetration depth was approximately 25-30 µm. In situ zymography showed that quercetin significantly inhibited the activities of dentin-derived MMPs. The inhibitory percentages of Q75 and Q150 were significantly lower than that of CHX (all P < 0.05), but no significant difference was found between Q300 and CHX (P = 0.58). The collagen crosslinking interactions with quercetin primarily involved hydrogen bonding and the degree of crosslinking increased in a concentration-dependent manner. Statistically significant increases in µUTS values were observed for demineralized dentin beams after quercetin treatment compared with those of the control treatments (all P < 0.05). SIGNIFICANCE: This study provides the first direct evidence that quercetin could penetrate approximately 25-30 µm into dentin and further prevent dentin erosion and abrasion by inhibiting dentin-derived MMP activity as well as crosslinking collagen of the demineralized organic matrix.

Effect of quercetin pretreatment on the immediate and aged bond strength of bleached dentin.

This in vitro study aimed to investigate the effect of quercetin pretreatment on the bond strength of bleached dentin. Human dentin blocks (2 × 2 × 1 mm) were prepared and randomly divided into 5 groups (n = 16): deionized water pretreatment + no bleaching treatment (DNB); deionized water pretreatment + bleaching treatment (DYB); 75 µg/mL quercetin pretreatment + bleaching (Q75B); 150 µg/mL quercetin pretreatment + bleaching (Q150B); and 300 µg/mL quercetin pretreatment + bleaching (Q300B). The surfaces of superficial dentin (bonding surfaces) were treated with the respective solutions for 2 min, and then the surfaces opposite to the bonding surfaces (near pulp, bleaching surfaces) were subjected to bleaching treatment with 40% hydrogen peroxide (Ultradent, USA) for two 15-min sessions (groups DYB, Q75B, Q150B, and Q300B). After the bleaching procedure, the bonding surfaces were bonded with resin cements (Panavia V5, Kuraray, Japan). The bonded specimens were then divided into 2 subgroups (n = 8): the aging group (subgroup T), which was subjected to 10,000 thermocycles, and the nonaging group (subgroup N), which was not subjected to thermocycling. The microshear bond strength (µSBS) was obtained using a universal testing machine (AGS-X, Shimadzu, Tokyo, Japan). Additional dentin blocks (5 × 5 × 1 mm) were prepared and treated the same as the groups DYB, Q75B, Q150B, and Q300B (n = 8) to evaluate the color change, defined as groups CCDYB, CCQ75B, CCQ150B, and CCQ300B, respectively. Color evaluation was performed using a spectrophotometer (Vita Easyshade Advance 4.0, Vident, USA) to obtain a baseline and again at the end of the bleaching treatment. The data were analyzed via two-way analysis of variance (ANOVA) and Tukey's post-hoc test (α = 0.05). For the immediate bond strength, the specimens in the groups Q75B, Q150B, and Q300B showed significantly higher µSBS values than those in the group DYB (all P < 0.05). No significant differences in the µSBS values were found among the groups Q75B, Q150B, Q300B, and DNB, respectively (all P > 0.05). For the aged bond strength, both the groups Q150B and Q300B exhibited significantly higher µSBS values than groups DYB and DNB (all P < 0.05), whereas no significance differences were found between groups Q150B and Q300B (P = 1.00) or between the groups DYB and DNB (P = 1.00). No significant differences were observed in the △E values among all the groups tested (P = 0.80). Therefore, the application of quercetin for 2 min prior to the bleaching procedure preserved the immediate bond strength and improved the aged bond strength of bleached dentin while maintaining the effectiveness of bleaching.

Detecting Proximal Caries on Periapical Radiographs Using Convolutional Neural Networks with Different Training Strategies on Small Datasets.

The present study aimed to evaluate the performance of convolutional neural networks (CNNs) that were trained with small datasets using different strategies in the detection of proximal caries at different levels of severity on periapical radiographs. Small datasets containing 800 periapical radiographs were randomly categorized into a training and validation dataset (n = 600) and a test dataset (n = 200). A pretrained Cifar-10Net CNN was used in the present study. Different training strategies were used to train the CNN model independently; these strategies were defined as image recognition (IR), edge extraction (EE), and image segmentation (IS). Different metrics, such as sensitivity and area under the receiver operating characteristic curve (AUC), for the trained CNN and human observers were analysed to evaluate the performance in detecting proximal caries. IR, EE, and IS recognition modes and human eyes achieved AUCs of 0.805, 0.860, 0.549, and 0.767, respectively, with the EE recognition mode having the highest values (p all < 0.05). The EE recognition mode was significantly more sensitive in detecting both enamel and dentin caries than human eyes (p all < 0.05). The CNN trained with the EE strategy, the best performer in the present study, showed potential utility in detecting proximal caries on periapical radiographs when using small datasets.

Case report: Application of metagenomic next-generation sequencing in the diagnosis of visceral leishmaniasis and its treatment evaluation.

Visceral leishmaniasis is a vector-borne infection by the Leishmania spp., a parasite. Although the overall incidence of visceral leishmaniasis is low, the disease still occurs frequently in some high-risk areas. In our study, two patients were admitted to the hospital with an unprovoked and recurrent high fever, and the condition was not improved after antibiotics administration. Meanwhile, bone marrow aspiration smears failed to find out any pathogen. Finally, Leishmania-specific nucleic acid sequences were successfully detected in the peripheral blood of two patients through metagenomic next-generation sequencing (mNGS), which was further confirmed by bone marrow smear microscopy and antibody tests. After targeted treatment for visceral leishmaniasis in the patients, mNGS reported a decrease in the reads number of Leishmania sequence. The results indicate the feasibility of mNGS in detecting Leishmania spp. in peripheral blood samples. Its therapeutic effect evaluation may be achieved through a comparative analysis of the number of reads before and after the treatment.

Is the bond strength of zirconia-reinforced lithium silicate lower than that of lithium disilicate? - A systematic review and meta-analysis.

PURPOSE: This study systematically reviewed the literature to compare the bond strength of resin composites with that of zirconia-reinforced lithium silicate (ZLS) and lithium disilicate (LD). STUDY SELECTION: This review was structured based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) statement. This study was registered at the International Prospective Register of Systematic Reviews (CRD42021256900). Studies were searched via PubMed, Web of Science, and Google Scholar databases without language or publication year limits. In vitro studies that evaluated the bond strength of the resin composites to ZLS and LD were included. The risk of bias in all the included articles was evaluated. Statistical analyses were performed using the Review Manager software (version 5.3, Cochrane Collaboration, Oxford, UK). RESULTS: Of the 90 potentially related articles, the full texts of 16 articles were evaluated after screening. Finally, seven studies were included in the qualitative synthesis and meta-analysis. All the studies presented a medium risk of bias. The results showed no significant difference in bond strength between the ZLS and LD groups (P = 0.94, mean difference=0.08, and 95% confidence interval=-1.93 to 2.10). However, a significant difference was found in the subgroup analysis considering different types of aging treatments (P = 0.0008) and different types of bond strength tests (P < 0.00001). CONCLUSION: The bond strength of resin composites was found to be similar to that of ZLS and LD, but different aging treatments and bond strength tests exhibited varying effects on the bond strength.

Does delayed toothbrushing after the consumption of erosive foodstuffs or beverages decrease erosive tooth wear? A systematic review and meta-analysis.

OBJECTIVE: Controversy exists regarding the effectiveness of delayed toothbrushing in decreasing erosive tooth wear (ETW). The purpose of this systematic review and meta-analysis was to assess the effects of delayed toothbrushing on ETW. MATERIALS AND METHODS: This systematic review and meta-analysis was conducted according to the PRISMA statement and registered in PROSPERO (CRD42020200463). PubMed, Embase, and Web of Science databases were systematically searched with no publication year limits. Screening and data extraction were performed independently by two reviewers. In situ and in vitro studies comparing ETW after delayed and immediate toothbrushing following an erosive attack were included. Review Manager software 5.3 (The Cochrane Collaboration, Oxford, UK) was used for statistical analyses. Heterogeneity was assessed with the Cochran Q test and I2 statistics. RESULTS: Of the 565 potentially relevant studies, 26 full-text articles were assessed for eligibility. Twelve articles were included in the systematic review, and 11 were included in the qualitative analyses. No significant difference in the ETW of human enamel was observed between delayed and immediate toothbrushing (P = 0.13), whereas significantly less ETW of bovine enamel was observed after delayed toothbrushing (P < 0.001). No significant difference in the ETW of bovine dentin was observed between delayed and immediate toothbrushing (P = 0.34). Studies on human dentin were not available. Subgroup analyses revealed a significant contribution of the use of fluoridated toothpaste to decreasing the ETW of human enamel after erosion and toothbrush abrasion (P = 0.02). CONCLUSIONS: Bovine and human teeth behaved differently in response to erosion and toothbrush abrasion. Delayed toothbrushing after an erosive attack was not effective at decreasing the ETW of human enamel compared to immediate toothbrushing, whereas it was effective at decreasing the ETW of bovine enamel. CLINICAL RELEVANCE: Delayed toothbrushing alone after the consumption of erosive foodstuffs or beverages is not capable of preventing erosive enamel wear.

Erosion of CAD/CAM restorative materials and human enamel: An in situ/in vivo study.

This in situ/in vivo study aimed to evaluate the effects of erosion on the surface microhardness, substance loss, and surface roughness of CAD/CAM restorative materials and human enamel. This study used a 2-treatment (14 days each) crossover design with 8 healthy volunteers. Each volunteer wore an intraoral appliance containing 3 CAD/CAM restorative material specimens [IPS e.max CAD, Lava Ultimate CAD/CAM Restorative, and a poly (methyl methacrylate) (PMMA) block for CAD/CAM] and 1 human enamel specimen. The specimens were subjected to in vivo erosion cycles by rinsing with 150 ml of cola drink (4 × 5 min/day) for 14 days. The surface microhardness, substance loss, and surface roughness of the specimens were measured at baseline (T1), day 7 (T2) and day 14 (T3). The data were statistically analyzed using repeated measures ANOVA and Tukey's test (α = 0.05). After erosion, significant increases in substance loss and surface roughness were observed for enamel, though the surface roughness and substance profile of the tested restorative materials remained unchanged. Erosion significantly decreased the surface microhardness of all materials. For IPS e.max and Lava Ultimate, a significantly higher percentage of surface microhardness loss (%SMHl) was found at T3 than at T2, while no significant difference was found between T2 and T3 for enamel and the PMMA block. In conclusion, CAD/CAM restorative materials showed smaller changes in surface roughness and the surface profile than human enamel after in situ/in vivo erosion. However, CAD/CAM restorative materials and human enamel showed similar changes in surface microhardness after in situ/in vivo erosion.

Quercetin reduces erosive dentin wear: Evidence from laboratory and clinical studies.

OBJECTIVE: The aim of the present study was to evaluate the effect of quercetin on the acid resistance of human dentin through both laboratory and clinical studies. METHODS: Two hundred and twelve dentin blocks (2 mm × 2 mm × 2 mm) were prepared and used. For the laboratory study, dentin specimens were randomly divided into 8 groups (n = 12): deionized water, ethanol, 1.23 × 104 µg/ml sodium fluoride (NaF), 120 µg/ml chlorhexidine, 183.2 µg/ml epigallocatechin gallate (EGCG), and 75 µg/ml, 150 µg/ml, and 300 µg/ml quercetin (Q75, Q150, and Q300). The specimens were treated with the respective solutions for 2 min and then subjected to in vitro erosion (4 cycles/d for 7 d). The surface microhardness loss (%SMHl), erosive dentin wear, and surface morphology were evaluated and compared. For the impact on MMP inhibition, the release of crosslinked carboxyterminal telopeptide of type I collagen (ICTP) and the thickness of the demineralized organic matrix (DOM) were measured using additional dentin specimens. For the clinical study, the specimens were treated with NaF or Q300 for 2 min and then subjected to in vivo erosion (4 cycles/d for 7 d). The %SMHl and erosive dentin wear of the specimens were measured to determine whether quercetin similarly inhibits erosion in situ. RESULTS: The quercetin-treated group had a significantly lower %SMHl and erosive dentin wear than any other group, and the effect was concentration-dependent in vitro (P < 0.05). Dentin treated with quercetin produced significantly less ICTP and had a thicker DOM than the control dentin (P < 0.05). After in vivo erosion, the %SMHl and erosive dentin wear of the Q300 group were significantly lower than those of the control group (P < 0.05). SIGNIFICANCE: The application of quercetin was shown, for the first time, to increase the acid resistance of human dentin, possibly through MMP inhibition and DOM preservation.

Knowledge of and attitudes towards erosive tooth wear among students of two Chinese universities.

BACKGROUND: To assess the knowledge of and attitudes towards erosive tooth wear among dental, medical, and non-medical university students of two Chinese universities. METHODS: A questionnaire containing 15 questions on knowledge of erosive tooth wear and 10 questions on attitudes towards erosive tooth wear was designed, and its psychometric properties (reliability and validity) were analysed in a pilot study (n = 120 students). The following 3 groups of university students (n = 635) were recruited based on a convenience sampling technique and were distributed the questionnaire via an online survey system: dental students (DSs), medical students (MSs), and non-medical students (NSs). Differences in the scores between groups and genders were analysed by one-way analysis of variance (ANOVA). The Pearson correlation coefficient was used to determine the association between the knowledge and attitude scores (P < 0.05). RESULTS: The questionnaire was found to be reliable, valid and reproducible. A total of 435 students participated in this study (response rate: 69.6%). The knowledge score of the DSs (11.5 ± 3.4) was significantly higher than those of the NSs (5.5 ± 4.0) and MSs (6.1 ± 4.0) (P < 0.001). The attitude score of the DSs (45.2 ± 6.5) was significantly higher than those of the NSs (41.1 ± 6.9) and MSs (41.8 ± 6.4) (P < 0.001). The majority of DSs expressed attitudes that were more accurate and positive than those expressed by the other 2 groups. The attitude score was positively correlated with the knowledge score (r = 0.237, P < 0.001). CONCLUSIONS: Dental students had more accurate knowledge of and more positive attitudes towards erosive tooth wear than medical and non-medical students. In this population, a positive correlation was established between knowledge of and attitudes towards erosive tooth wear.

Short-term effects of stain-causing beverages on tooth bleaching: A randomized controlled clinical trial.

OBJECTIVES: To evaluate the short-term effects of stain-causing beverages on the effectiveness of in-office tooth bleaching. METHODS: Participants were recruited and randomly divided into 3 groups based on beverages used for rinsing during and after the bleaching procedure: group N (tap water, control group), group C (coffee), and group T (tea). Participants were instructed to rinse with the respective solutions for 30 s, 4 times daily for 4 weeks. All participants received two in-office bleaching treatment sessions with 40 % hydrogen peroxide (Opalescence BOOST PF 40 %, Ultradent); the sessions were separated by a 1-week interval. Tooth colour was assessed using a spectrophotometer (Easyshade, Vita ZahnFabrik) before the bleaching procedure (T0), immediately after the first session of bleaching (T1), immediately after the second session of bleaching (T2), as well as one week (T3) and three weeks after (T4) the end of bleaching. Tooth sensitivity (TS) was ranked using a numerical rating scale (NRS) and a visual analogue scale (VAS) at different time points. RESULTS: No significant difference in the whiteness index (W), △E, △a* and △b* values among the 3 groups was observed at any time interval (P for all > 0.05). At T4, the △L* value in group C was significantly lower than that in groups T and N (P = 0.022 and P = 0.001, respectively), though no significant difference in △L* values was observed among the 3 groups at T1 (P = 0.402), T2 (P = 0.643) and T3 (P = 0.177). Additionally, no significant difference was found in the TS values among the 3 groups at any of the evaluation time points (P for all > 0.05). CONCLUSIONS: Exposure to coffee or tea during the bleaching treatment period did not affect the effectiveness of the treatment. However, exposure to coffee after the bleaching treatment did affect the effectiveness of the treatment. Exposure to stain-causing beverages did not affect the bleaching-induced TS (ClinicalTrials.gov Identifier: NCT03933527). CLINICAL SIGNIFICANCE: The consumption of coffee or tea during tooth bleaching may not interfere with the colour change produced by the treatment. However, clinicians should advise their patients to refrain from, at least to some extent, consuming coffee after the bleaching procedure to maintain the effectiveness of the treatment.

The complete chloroplast genome sequence of Oryza eichingeri (Poaceae).

The complete chloroplast genome sequence of Oryza eichingeri (GenBank accession number: KX085496) was generated by de novo assembly with low-coverage whole-genome sequence data. The chloroplast genome is 134,821 bp in length and showed conserved typical chloroplast structure. The cpDNA contained four rRNA, 39 tRNA, and 79 unique protein-coding genes. Seventeen genes contain one intron, only ycf3 contains two introns; rps12 is trans-spliced, one of its exons is in the LSC region (5'_end) and the two reside in the IR regions (3'_end) separated. A pair of gene ndhH, due to the 5' part of ndhH which overlaps the IR/SSC junctions, was two unique genes. The AT content of O. eichingeri cp genome is 61%. Phylogenomic analysis showed that O. eichingeri is closely related to O. officinalis. The complete cpDNA of O. eichingeri provides essential and important DNA molecular data for further phylogenetic and evolutionary analysis for the genus Oryza.

The complete chloroplast genome sequence of Oryza rhizomatis (Poaceae).

The complete chloroplast genome sequence of Oryza rhizomatis (GenBank accession number: KX085497) was generated by de novo assembly with low-coverage whole-genome sequence data. The genome was 134,796 bp in length, containing a pair of inverted repeat (IRa and IRb) regions of 20,818 bp, which were separated by a large single-copy (LSC) region of 80,829 bp and a small single-copy (SSC) region of 12,330 bp, respectively. The genic regions account for 43.77% of whole cpDNA, and the AT content of the cpDNA was 60.99%. The O. rhizomatis cpDNA encodes 112 unigenes (79 protein-coding genes, four rRNA genes, and 29 tRNA genes). Eighteen genes contain introns, ycf3 contains two introns, and the rest of the gene contains one intron; rps12 is trans-spliced, one of its exons is in the LSC region (5'_end) and the two reside in the IR regions (3'_end) separated. A pair of gene ndhH, due to the 5' part of ndhH which overlaps the IR/SSC junctions, was two unique genes. The four rRNA genes are all located in the IR. Phylogenomic analysis showed that O. rhizomatis is closely related to O. officinalis. The new data will help to determine the phylogenetic placement of the genus Oryza and fill gaps in our understanding of Oryzae biology.

Molecular cloning, genomic structure, polymorphism and expression analysis of major histocompatibility complex class IIA gene of swamp eel Monopterus albus.

Major histocompatibility complex (MHC) class II molecules play an important role in the immune response of vertebrates. In this paper, full-length MHC IIA cDNA was isolated from swamp eel (Monopterus albus) by rapid amplification of cDNA ends PCR. The genomic structure, molecular polymorphism, tissue distribution, and immune response of the MHC IIA gene to bacterial challenge were investigated. The full-length cDNA (GenBank accession No.: KC616308) is 1,509 bp in length including an 83 bp-long 5' untranslated region (UTR) and a 709 bp-long 3' UTR, which encoded a 238 amino acids protein. In the 2,339 bp-long MHC IIA genomic DNA, four exons and three introns were identified. Sequence comparison exhibited that the deduced amino acid sequence shared 27.1-66.3% identity with those of other species. Seven alleles were identified from five healthy individuals. Number of alleles per individual diversified from two to five. Five different 5' UTR sequences and two different 3' UTR sequences from one individual may infer the existence of five loci at least. Real-time quantitative PCR demonstrated that swamp eel MHC IIA transcripts were ubiquitously expressed in ten tissues, but the expression level was distinctly different. Significant changes were observed in liver, spleen, kidney and intestine after challenged with pathogenic bacteria Aeromonas hydrophilia.