Breakup of the proton halo nucleus 8B near barrier energies.

The dynamics of a nuclear open quantum system could be revealed in the correlations between the breakup fragments of halo nuclei. The breakup mechanism of a proton halo nuclear system is of particular interest as the Coulomb polarization may play an important role, which, however, remains an open question. Here we use a highly efficient silicon detector array and measure the correlations between the breakup fragments of 8B incident on 120Sn at near-barrier energies. The energy and angular correlations can be explained by a fully quantum mechanical method based on the state-of-the-art continuum discretized coupled channel calculations. The results indicate that, compared to the neutron halo nucleus 6He, 8B presents distinctive reaction dynamics: the dominance of the elastic breakup. This breakup occurs mainly via the short-lived continuum states, almost exhausts the 7Be yield, indicating the effect of Coulomb polarization on the proton halo state. The correlation information reveals that the prompt breakup mechanism dominates, occurring predominantly on the outgoing trajectory. We also show that, as a large environment, the continuum of 8B breakup may not significantly influence elastic scattering and complete fusion.

MiR-940 inhibits the progression of NSCLC by targeting FAM83F.

OBJECTIVE: We investigate whether miR-940 could target family sequence similarity 83 member F (FAM83F) and further inhibit the progression of non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: The expression levels of miR-940 and FAM83F in tumor tissues and paracancerous tissues of 72 NSCLC patients were detected through quantitative real time-polymerase chain reaction (qRT-PCR). The relationship between their expression levels, tumor size, and prognosis of NSCLC was analyzed. Transfection plasmids were constructed to knockdown or overexpress miR-940 in H1299 cells (inhibitor group) and SK-MES-1 cells (mimic group). The viability of H1299 cells and SK-MES-1 cells was evaluated using cell counting kit-8 (CCK-8) assay after transfection. The combination of miR-940 and Ago2 was confirmed by RNA immunoprecipitation (RIP) experiment. The binding condition of miR-940 in FAM83F-WT and FAM83F-MUT groups was verified by luciferase reporter gene assay. RESULTS: MiR-940 expression was noticeably decreased, while FAM83F expression was distinctly upregulated in NSCLC tissues than that of paracancerous tissues. The overall survival rate of NSCLC patients with highly-expressed miR-940 was significantly higher than those with lowly-expressed miR-940. Besides, miR-940 level was negatively correlated with tumor stage and size of NSCLC patients. Knockdown of miR-940 evidently enhanced the activity of H1299 cells, while overexpression of miR-940 decreased the viability of SK-MES-1 cells. In addition, miR-940 was confirmed to combine with FAM83F. Luciferase activity of cells co-transfected with FAM83F-WT and miR-940 mimic was significantly decreased. CONCLUSIONS: MiR-940 inhibited the proliferation of cancer cells by targeting FAM83F and further restrained the progression of NSCLC.

Apoptosis in the regenerate produced by mandibular osteodistraction in the mature rat.

UNLABELLED: AUTHORS: Liu ZJ, Anderson MW, Gu GM, King GJ. OBJECTIVE: Little is known about the contribution of apoptosis to the formation of the regenerate in distraction osteogenesis. This study investigated the role of apoptosis in the regulation of osteogenesis in relation to mandibular distraction rate and recovery time. METHODS: One hundred and twenty-nine 3-month rats received unilateral mandibular ramus osteotomy and distraction device placement. After 3-day latency, these were distracted for 5 days. The slow group was distracted a total of 1 mm (0.2 mm/day), the moderate 2 mm (0.4 mm/day), the rapid 3 mm (0.6 mm/day), and the sham was not distracted (0.0 mm/day). Eight to nine rats from each group were killed at 6 (mid-distraction), 10 (early-consolidation), 24 (mid-consolidation) and 38 (late-consolidation) days following device placement. Baseline data were obtained from an additional eight rats killed at day 3 (end of latency). Sagittal sections (7 mum) of the harvested hemi-mandibles were embedded in paraffin, double-stained with the DeadEnd(TM) Colorimetric TUNEL system for apoptotic cells and tartrate-resistant acid phosphatase for osteoclasts. Cell counts of apoptotic cells and osteoclasts (apoptotic or otherwise) were preformed at 40x magnification using a calibrated grid at the middle regions of the caudal, central and rostral parts of the distraction gap. Counting reproducibility was verified as <13%. RESULTS: Counts from all three regions were combined because no significant regional difference was found. The majority of the fibrous matrix regenerate was seen at days 6 and 10 while osseous regenerate occurred mainly at days 24 and 38. Significantly higher levels of apoptotic activity were seen at day 24. Apoptotic osteoclasts also peaked at day 24. Apoptotic cell numbers in the slow and moderate groups most closely followed the pattern of the sham in which the apoptosis activity peaked at days 10 or 24. However, those in the rapid group showed delayed peaks at days 24 or 38. CONCLUSIONS: Chalmers Street, Surry Hill, NSW 2010, Australia. gshe6437@mail.usyd.edu.au The transition from fibrous to osseous regenerate during mandibular distraction osteogenesis is accompanied by an increase in cell clearance via apoptosis. A slow to moderate distraction rate allows for the most typical pattern of bone healing while a rapid rate prolongs the healing process.

Muscle fibre composition and electromyographic features of cervical muscles following prolonged head extension in growing rats.

Soft tissue stretching has been proposed as one of the control factors in craniofacial morphogenesis. However, its mechanism remains unclear. The present study investigated electromyographic (EMG) activity and muscle fibre composition of cervical muscles following prolonged head extension in growing rats. Thirty-six male Wistar rats were divided into two experimental (E1, E2) and one control (C) group at 25 days of age. To induce head extension, the experimental rats were raised in cylindrical cages, which were positioned horizontally for group E1 and tilted upward at 45 degrees for group E2. At 55 days of age, EMG activity was recorded from the anterior digastricus (AD), sternohyoideus (SH), sternomastoideus (SM), longus capitis (LC), and biventer cervicis (BC) muscles in the rest position and passive head extension. EMG activity was analysed on its integrated values (IEMG), and composition of muscle fibres was evaluated by myosin ATPase reaction and fibre cross-sectional areas were calculated. Group E1 showed a higher percentage of type I fibres and lower IEMG during passive head extension in AD. In group E2 there was a higher percentage of type I fibres, a higher IEMG at rest, and a lower IEMG during passive head extension in BC. The experimental groups demonstrated altered proportions of type IIA and IIB fibres in SM and LC. They also showed higher percentages of subtype fibres and reduced cross-section areas of type II fibres in most of the muscles investigated. These findings suggest that head extension affects fibre transition, distribution, cross-section area, and recruitment pattern in cervical muscles.

Intermittent force in orthodontic tooth movement.

A single orthodontic activation lasting one hour can initiate tooth movement. The purpose of this study is to examine tooth movement, osteoclasts, and root resorption in rats following several one-hour activations. Rats (n = 144) were randomly assigned to intermittent (multiple activations of 1 hr/day), continuous, and sham appliances. Twelve rats were killed at 3, 5, 7, and 14 days. Tooth movement, osteoclasts, osteoclast %, and root resorption % were quantified. Continuous force moved molars mesially at days 3 and 14 (p < 0.05), but intermittent and sham did not. Intermittent and continuous force increased osteoclast numbers at days 3, 5, and 7 (p < 0.05). Continuous force increased osteoclast surface on days 3 and 14 (p < 0.05). Continuous force increased root resorption at days 5, 7, and 14 (p < 0.05). These results demonstrate that orthodontic force for one hour in 24 stimulates osteoclasts at compression sites but does not stimulate tooth movement or root resorption.

[Studies on the alkaloids of Gynura segetum (Lour.) Merr].

Six alkaloids were isolated from Gynura segetum (Lour.) Merr. Four of them were identified. Alkaloids I and II were identified as known senecionine and seneciphylline, respectively. Alkaloids III and IV were found to be new compounds named seneciphyllinine and (E)-seneciphylline respectively. Their structures were confirmed on the basis of spectral data (UV, IR, MS, 1HNMR, 13CNMR, C-H COSY).