Whole-genome sequence and characterization of a marine red yeast, Rhodosporidium sphaerocarpum GDMCC 60679, featuring the assimilation of ammonia nitrogen.

A marine red yeast, Rhodosporidium sphaerocarpum, is generally used for the production of lipids and carotenoids. In a previous study, we demonstrated that a marine-derived R. sphaerocarpum GDMCC 60679 can efficiently remove ammonia nitrogen and exhibit multiple probiotic functions for shrimp, Litopenaeus vannamei. Here, we performed a genome assembly of the strain GDMCC 60679 using a combination of the data from Illumina PE and PacBio CLR reads. The genome has a size of 18.03 Mb and consists of 32 contigs with an N50 length of 1,074,774 bp and GC content of 63 %. The genome was predicted to contain 6092 protein-coding genes, 5962 of which were functionally annotated. Metabolic pathways responsible for the ammonia assimilation and the synthesis of lipids and carotenoids were particularly examined to explore and characterize genes contributing to these functions. Whole-genome sequence and annotation of the strain lays a foundation to reveal the molecular mechanism of its prominent biological functions and will facilitate us to further expand new applications of yeasts in Rhodosporidium.

Genomic and biological characteristics of a newly isolated lytic bacteriophage PZJ0206 infecting the Enterobacter cloacae.

Enterobacter cloacae is an opportunistic pathogen that widely distributes in various environments, often causing hospital and community-acquired infections. The limited phage resources and poor genomic data hinder the understanding of the lysis mechanism of Enterobacter cloacae phages. In the present study, we characterized a newly discovered lytic phage PZJ0206 that infects an E. cloacae strain isolated from sewage water into the Pearl River in Guangdong, China. The morphological characteristics of the icosahedral head and short tail of PZJ0206 were observed by transmission electron microscopy. The one-step growth curve showed that PZJ0206 has a relatively short latent period and an average burst size of approximately 124 PFU (plaque forming unit)/infected cell at an MOI of 0.1. The genome of phage PZJ0206 consists of 40,526 bp with a GC content of 48.62% and contains 45 putative open reading frames (ORFs). Based on genomic characteristics, comparative genomics and phylogenetic analysis, it was strongly demonstrated that PZJ0206 is a novel member of the genus Berlinvirus in the family Autographiviridae. Our work provides basic information on Enterobacter cloacae phage PZJ0206 and lays the foundation for the further study of the evolution of phage PZJ0206 and interactions between the phage and its host.

CAD/CAM techniques help in the rebuilding of ideal marginal gingiva contours of anterior maxillary teeth: A case report.

BACKGROUND AND OVERVIEW: "Pink esthetics," which are considered to be as important as "white esthetics," have attracted increasing attention. To date, clinicians rarely have applied computer-aided design and computer-aided manufacturing (CAD/CAM) techniques in the rebuilding of the contour of the marginal gingiva in the esthetic zone. CASE DESCRIPTION: In this case report, the authors describe a female patient who had gingival inflammation and an asymmetrical contour of the marginal gingiva of the anterior maxillary teeth because previously placed ceramic crowns violated the biological width. The authors used a 3-dimensional-printing surgery template to guide precise crown-lengthening surgery to expose subgingival shoulders and to obtain an ideal marginal gingival contour. Then the authors used interim CAD/CAM crowns to induce the growth of the interdental papilla by 0.5 to 1.5 millimeters. Finally, the patient had a symmetrical and well-balanced contour of the marginal gingiva. In addition, the authors reduced the patient's "black triangle" areas to the greatest possible extent. CONCLUSIONS AND PRACTICAL IMPLICATIONS: This case report illustrates that CAD/CAM products, including 3-dimensional-printing surgery templates and CAD/CAM interim crowns, are helpful in shaping and rebuilding the ideal contour of the marginal gingiva in the esthetic zone, such as the anterior maxillary teeth.

[Evaluation on the application of mechanical toothguide training box to chromatics teaching of prosthodontics].

OBJECTIVE: To evaluate the effectiveness on the application of mechanical toothguide training box (TTB) to chromatics teaching of prosthodontics. METHODS: 12 preclinical undergraduate students were chosen to participate in the VITA 3D-Master shade-matching system simulant toothguide training process using Linearguide Training Box program of TTB. Toothguide Trainer program considered as a test was performed on the trained undergraduate students group, the postgraduate students group as well as the clinical prosthodontists group with under 5-year clinical experience. The test scores, elapsed time and the coincidence of chromatics single factor matching were recorded each time, the shade-matching efficiency was calculated. The data was analyzed with SPSS 13.0 software. RESULTS: The shade-matching efficiency of undergraduate students trained by TTB (64.03 +/- 18.82) was significantly higher than before (P < 0.05), higher than the postgraduate students group and the clinical prosthodontists group (P < 0.05). The coincidence of chromatics single factor matching of trained undergraduate students were 64.64% (lightness), 88.57% (chroma), 87.70% (hue). CONCLUSION: TTB is a effective tool for shade-mathing practice in chromatics teaching of prosthodontics. The trained undergraduate students are less sensitive in lightness-matching.

[Study on the compatibility of yttria-stabilized zirconia framework bonded to the corresponding veneering ceramic].

OBJECTIVE: To investigate the bonding properties and interface characterization of a domestic 3mol yttrium-stabilized tetragonal zirconium polycrystal (3Y-TZP) framework fired on with 4 different veneering ceramics for zirconia. METHODS: 4 different commercial veneering ceramics for zirconia (VITA VM9, SHOFU VINTAGE ZR, IPS e.max Ceram, Cercon ceram kiss) were sintered on 3Y-TZP rectangulars (15 mmx5 mmx5 mm) according to the manufacturers' instructions for shear bond strength test, a metal-ceramic system(Ni-Cr alloy/VITA VMK95) was fabricated in the same type as a control group. Two bilayered specimens (3Y-TZP/VITA VM9, Ni-Cr/VMK95) were prepared for scanning electron microscope (SEM) and energy distribution spectrum (EDS). RESULTS: The values of shear bond strength test were (18.83 +/- 1.77) MPa for 3Y-TZP/VITA VM9, (23.83 +/- 7.05) MPa for 3Y-TZP/SHOFU VINTAGE ZR, (17.87 +/- 2.30) MPa for 3Y-TZP/IPS e.max Ceram, (22.26 +/- 7.45) MPa for 3Y-TZP/Cercon ceram kiss, (20.55 +/- 5.13) MPa for Ni-Cr alloy/VITA VMK95. There was no statistically significant between all-ceramic groups and the control group (P > 0.05). The failure modes in all-ceramic groups showed predominately adhesive at the interface. SEM showed the 3Y-TZP/VITA VM9 contacted tightly at the interface, while EDS detected Si element diffused into 3Y-TZP material. CONCLUSION: The results indicate that domestic 3Y-TZP has a good interface compatibility with 4 commercial veneering ceramics, as a dental framework material, it can satisfy the clinical requirements.