[Research advancements of two-dimensional black phosphorus in dentistry].

Two-dimensional black phosphorus (BP) has unique layered structure, excellent photothermal properties, good biocompatibility and high biodegradability. In recent years, it has been found that BP has stable drug loading and light controlled sustained-release drug functions, excellent antibacterial properties and the ability to promote vascular and nerve regeneration in the medicine field, which has a broad application prospect in dentistry. This review elaborates the biological properties of two-dimensional BP and its application progress in dentistry, so as to provide new ideas for the further research and application of two-dimensional BP.

[Application of arthrography with cone-beam CT imaging in the diagnosis of temporomandibular disorders].

Objective: To evaluate the meaning of arthrography with cone-beam CT（CBCT） imaging in the diagnosis of temporomandibular disorders(TMD). Methods: Four hundred and forty-eight cases of temporomandibular upper joint cavity arthrography with CBCT imaging were retrospectively analyzed. The distribution of disc displacement with reduction or without reduction, disc perforation, enlargement or tearing of joint capsule were analyzed. The characteristics of arthrography with CBCT imaging were also described. Results: There were 384 female and 64 male among the 448 cases of TMD with CBCT arthrographic images. The median age was 31.5 years， range from 14 to 81 years old. As about the age distribution, there were 63 cases in the group of ≤20 years old, 150 cases in the group of >20 and ≤30 years old, 86 cases in the group of >30 and ≤40 years old, 59 cases in the group of >40 and ≤50 years old, 58 cases in the group of>50 and ≤60 years old, and 32 cases in the group of >60 years old. There were 356 cases with disc displacement, in which there were 328 cases of disc displacement without reduction, and 28 cases of disc displacement with reduction. There were 152 cases with disc perforation, and 12 cases with articular capsule tearing or laxation. Conclusions: Arthrography with CBCT imaging was a meaningful approach to diagnose the TMD with structure disorders.

Sequence variability in three mitochondrial DNA regions of Spirometra erinaceieuropaei spargana of human and animal health significance.

Sequence variability in three mitochondrial DNA (mtDNA) regions, namely cytochrome c oxidase subunit 3 (cox3), NADH dehydrogenase subunits 1 and 4 (nad1 and nad4) in Spirometra erinaceieuropaei spargana from different geographical regions in China was examined. A portion of each of the cox3 (pcox3), nad1 (pnad1) and nad4 genes (pnad4) were amplified separately from individual S. erinaceieuropaei spargana by polymerase chain reaction (PCR). Representative amplicons were subjected to sequencing in order to estimate sequence variability. The sequences of pcox3, pnad1 and pnad4 were 541, 607 and 847 bp in length, respectively. The A+T contents of the sequences were 68.39-68.76% (pcox3), 63.76-64.91% (pnad1) and 67.18-67.77% (pnad4), respectively, while the intra-specific sequence variations within each of the S. erinaceieuropaei spargana were 0-1.5% for pcox3, 0-2.8% for pnad1 and 0-2.7% for pnad4. Phylogenetic analysis using neighbour joining (NJ), maximum likelihood (ML) and maximum parsimony (MP) methods, indicated that all the spargana isolates in Hunan Province represented S. erinaceieuropaei. These findings demonstrated clearly the usefulness of the three mtDNA sequences for population genetics studies of S. erinaceieuropaei spargana of human and animal health significance.

Survey of Spirometra erinaceieuropaei spargana infection in the frog Rana nigromaculata of the Hunan Province of China.

The prevalence of spargana infection in frogs (Rana nigromaculata) was investigated in China's central Hunan Province, from March 2007 to October 2009. 59 of 292 (20.2%) wild-caught frogs were found to be infected with plerocercoids (spargana) of the genus Spirometra. Spargana were recovered from the skeletal muscle of the hind limb. The infection rate ranged from 4.5% to 27.4%, and the infection intensity was 1-15 spargana per frog. To identify the species identity of the collected spargana, a portion of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene was amplified, sequenced, and analyzed. Sequence variations for cox1 among all the examined spargana were 0.0-3.1%, with 14 variable sites being identified in sequences obtained (3.1%, 14/446), representing 6 different cox1 sequences. Phylogenetic analysis showed that all the spargana isolates in Hunan province represented Spirometra erinaceieuropaei. This is the first report of S. erinaceieuropaei infection in frogs in Hunan province, China.

[QTLs analysis of tiller angle in rice (Oryza sativa L.)].

Tiller angle is one of important characters that constitute plant type with great significance in breading. A pair of japonica/indica lines, which were significantly different in tiller angle, were used in this study. A DH population were constructed via anther culture of F1 hybrids. The tiller angles of 115 DH lines were measured. QTL analysis was conducted based on the constructed molecular linkage map. Three QTLs (qTA-9a, qTA-9b and qTA-12) were detected on chromosome 9 and 12 respectively, Their variation were 22.7%, 11.9% and 20.9% respectively and their additive effects were all negative, showing this character was controlled by genes from big tiller angle parent ZYQ8. The application of the tiller angle that was controlled by major genes and minor genes in rice breeding is also discussed.

Use of combinatorial mutagenesis to select for multiply substituted human interleukin-3 variants with improved pharmacologic properties.

A combinatorial mutagenesis strategy was used to create a collection of nearly 500 variants of human interleukin 3 (IL-3), each with four to nine amino acid substitutions clustered within four linear, nonoverlapping regions of the polypeptide. The variants were secreted into the periplasm of Escherichia coli and supernatants were assayed for IL-3 receptor-dependent cell proliferation activity. Sixteen percent of the variants, containing "region-restricted" substitutions, retained substantial proliferative activity through two rounds of screening. A subset of these was combined to yield variants with substitutions distributed through approximately half of the polypeptide. With one exception, "half-substituted" variants exhibited proliferative activity within 3.5-fold of native IL-3. A subset of the "half-substituted" variants was combined to yield "fully substituted" IL-3 variants having 27 or more substitutions. The combination of the substitutions resulted in a set of polypeptides, some of which exhibit increased proliferative activity relative to native IL-3. The elevated hematopoietic potency was confirmed in a methylcellulose colony-forming unit assay using freshly isolated human bone marrow cells. A subset of the multiply substituted proteins exhibited only a modest increase in inflammatory mediator (leukotriene C4) release. The molecules also exhibited 40- to 100-fold greater affinity for the alpha subunit of the IL-3 receptor and demonstrated a 10-fold faster association rate with the alpha-receptor subunit. The multiply substituted IL-3 variants described in this study provide a unique collection of molecules from which candidates for clinical evaluation may be defined and selected.

[Genetic analysis on a new sterile locus discovered in hybrids between indica and japonica rice (Oryza sativa L.)].

Japonica line 02428, possessing wide compatibility gene S-5n, showed semi-sterility as crossed with indica variety IR24. Genetic analysis was conducted on the spikelet fertility in segregation generations from the crosses of 02428 with IR24, Pecos and Akihikara. The results indicated that the sterility in hybrids between 02428 and IR24 was controlled by a single non-allelic to S-5 gene and its inheritance fitted to one-locus sporo-gametophytic interaction model. Pecos, an American variety, has a neutral allele. The new sterility locus was preliminarily located near G24 marker on chromosome 11 detected by RFLP. The non-allelic S-locus in the study is named tentatively S-p(t). It was found that the sterility caused by the cross of Akihikara and IR24 was controlled by two S-loci, S-5 and S-p(t), and its genetical effect was additive.