Two Divergent Enyne Cycloisomerization Routes Mediated by Monoallenylidene Pd(II) Catalysts.

The catalytic application of four monoallenylidene bisphosphine Pd(II) catalysts, which were developed using alkynyl triazole salt as the allenylidene source, in the cycloisomerization of 1,6-enyne was explored. Two divergent reaction pathways, including a new type of intramolecular Alder-ene (IMAE) route and a routine cycloisomerization route, were developed using either complex TAA(Et3P)2-PdCl·BF4- 3b or TAA(Ph3P)2-PdCl·BF4- 3c as the catalyst precursor.

Gold catalyzed efficient preparation of dihydrobenzofuran from 1,3-enyne and phenol.

A gold catalyzed formal intermolecular [2+3] cyclo-coupling of 1,3-enynes with phenols was developed to prepare dihydrobenzofuran derivatives with the addition of 2,6-dichloropyridine N-oxide, in which, a highly ortho-selective phenol SEAr functionalization was achieved by using 1,3-enynes as α-oxo vinyl gold carbenoid surrogates.

[Effect of bilateral sagittal split ramus osteotomy on temporomandibular joint symptom and condylar position in patients with skeletal class â ¢ malocclusion by cone beam computed tomography].

OBJECTIVE: To investigate the effect of bilateral sagittal split ramus osteotomy (BSSRO) on temporomandibular joint (TMJ) symptom and condylar position in patients with skeletal class Ⅲ malocclusion treated with orthodontic-orthognathic surgical treatment. METHODS: Twenty-four patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgical treatment were included in the study. Their cone-beam computed tomography scans and TMJ symptom were evaluated, and their Helkimo index before BSSRO, 1 month after BSSRO, and 12 months after BSSRO was recorded. The maximum diameter of the horizontal and coronal sections, short axis diameters, neck width, height, joint space widths at different angles (45°, 90°, and 135°) of the condylar joint, bilateral condylar spacing, and different condylar angles (horizontal angle, vertical angle, and stress angle) in three dimensions were measured. Then, the changes in TMJ symptom and bone structure at different periods were analyzed. RESULTS: The Helkimo index was anamnestic (Ai) or dysfunctional (Di) levels 0 or 1 before and after BSSRO, and no difference in Helkimo index was observed. The horizontal angle and joint space widths at 45° and 90° increased whereas the joint space width at 135° decreased at 1 month after BSSRO compared with before BSSRO (P<0.05). Except for the increase in condylar horizontal angle (P<0.05), no significant difference in other measurement items was noted (P>0.05) 12 month after BSSRO. CONCLUSIONS: BSSRO would not have a remarkable effect on the TMJ symptom and condylar position of patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgical treatment procedure and whose Helkimo index ranked Ai0, Ai1, Di0, and Di1.

Gold-Catalyzed Diastereoselective Formal Intermolecular [4 + 2 + 1] Cycloaddition of 1,3-Dien-8-yne with Diazo Ester.

The first example of gold-catalyzed formal intermolecular [4 + 2 + 1] cycloaddition was developed using 1,3-dien-8-yne as C4 and C2 units and diazo ester as the C1 unit, which provides expedient access to a series of structurally complicated [5.3.0] bicyclic adducts in moderate yields with moderate to high diastereoselectivities. The key route involved a cascade process of dienyne cycloisomerization, cyclopropyl gold carbene's trapping, and subsequent divinyl cyclopropane (DVCP) Cope rearrangement.

The impacts of the number of prefreeze and postthaw blastomeres on embryo implantation potential: A systematic analysis.

To systematically analyze the potential of embryo implantation through comparison between the number of surviving blastomeres, the growth, and implantation rate.Retrospective analysis on implantation rate and the growth of prefreeze-postthaw embryos with different blastomeres in 1487 frozen embryo transfer cycles.In groups of postthaw embryos without damage, implantation rate and the average number of blastomere growth increased significantly with increasing number of blastomeres. The implantation rate and the number of blastomeres of embryos with 8-8c (the number of blastomeres in prefreeze embryo-the number of blastomeres in postthaw embryo) continued to grow at a significantly higher rate than that of 5-5c and 6-6c (P < .05). In groups of embryos with the same number of blastomeres before freezing and with partial damage after resuscitation, the implantation rates were lower and the average numbers of blastomere growth reduced as the number of damaged blastomeres increased. For embryos with good quality before freezing, 1 to 3 damaged blastomeres in postthawed embryos did not affect the development and implantation rate. Both implantation rate and growth rate of embryos with 8-6c were significantly higher than those of embryos with 6-6c (P < .05).The number of surviving blastomeres and growth in frozen-thawed embryos could be important index to predict embryo development potential and clinical outcome of implantation. For embryos with good quality, a small amount of damaged blastomeres would not weaken embryo development potential and implantation rate after being thawed.

[Investigating the effect of pre-surgical orthodontic treatment on temporomandibular joint in patients with skeletal class â ¢ malocclusion by cone-beam computed tomography].

OBJECTIVE: To investigate the effect of pre-surgical orthodontic treatment on temporomandibular joint (TMJ) in patients with skeletal class Ⅲ malocclusion treated with orthodontic-orthognathic surgical treatment. METHODS: Twenty-four patients with skeletal class Ⅲ malocclusion who underwent orthodontic-orthognathic surgical treatment were included in the study. Before and after the completion of orthodontic treatment, the symptoms of TMJ were examined and recorded, and the short- and the long-axis diameter of the condylar (d), condylar height (h), joint space (L) at different angles, bilateral condylar spacing (R), and the condylar angles were measured, with scanning performed by using cone-beam computed tomography (CBCT). Then, the changes of TMJ symptoms and bone structure at different periods were analyzed. RESULTS: No significant changes were observed in the joint symptoms before and after the pre-surgical orthodontic treatment. No significant changes were found in the measurements of the bone structure of TMJ in the dimensional direction (P>0.05). CONCLUSIONS: In the orthodontic-orthognathic surgical treatment procedure, the pre-surgical orthodontic process does not have a significant effect on TMJ.

[Application of participatory teaching mode in oral health education].

PURPOSE: To apply participatory teaching mode in oral health education, and to assess its role in cultivating comprehensive stomatological professionals suitable for the development of modern medicine. METHODS: Sixty undergraduate students from grade 2005 in Stomatological College of Nanchang University were selected. Among those students, oral health education course was carried out by traditional teaching mode, while 120 undergraduate students from grades 2006 to 2007 received participatory teaching approach, which paid attention to practice in oral health education practice course. After the course, a survey and evaluation of teaching effectiveness was conducted. RESULTS: Questionnaire survey showed that participatory teaching mode could significantly improve the students' capabilities and provide much more help to their study. CONCLUSIONS: Application of participatory teaching mode in oral health education course for undergraduates is feasible. It can improve students' comprehensive ability and cultivate their cultural literacy and scientific literacy. It also meets the training goal of stomatological professionals and the development trend of education reform. Supported by Higher School Teaching Reform Research Subject of Jiangxi Province(JXJG-10-1-42).

[The influence of autogenous bone graft in cleft palate on maxillary growth: an experiment study in rats].

PURPOSE: This study was designed to investigate the influence of autogenous bone graft in cleft palate on maxillary growth in rats. METHODS: Forty Wistar strain male rats aged 4 weeks were randomly divided into four groups. Each group had 10 rats. Group 1 was the unoperated control group. Group 2 had a surgically created cleft palate but unrepaired. Group 3 also had a surgically created cleft palate which followed by a two-flap palatoplasty repair immediately. Group 4(experimental group) also had a surgically created cleft palate, but the cleft palate was reconstructed by autogenous rib graft with two-flap repair. All animals were sacrificed on the 10th week after operation. The data were analyzed using SPSS. And one-way ANOVA was used for comparison of the four groups. RESULTS: The experimental group was significantly smaller than unoperated control group and cleft palate group in the maxillary widths variables, length variables (AD),height variables(P<0.01).Except rats in the experimental group had significantly greater posterior palate width than rats in two-flap repair group(P<0.01),there were no significant difference between the two procedures in maxillary growth variables(P>0.05).But the experimental group was smaller in the maxillary heights, length variables than the two-flap group. CONCLUSIONS: These findings showed that repair of the cleft palate by autogenous rib graft had positive effect on preventing the contraction of maxillary width. But in the maxillary anteroposterior and vertical development, the experimental group possibly had more severe retardation than two-flap repair group.