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Given the powerful potential of chiral-at-silicon chemistry, enantioselective synthesis of Si-stereogenic centers has attracted substantial research interest in recent years. However, the catalytic asymmetric synthesis of Si-stereogenic organosilicon compounds remains an appealing venture and is a challenging subject because of the difficulty in achieving high reactivity and stereoselectivity for "silicon-center" transformations. Herein, we disclose a highly enantioselective palladium-catalyzed hydrosilylation of 1,3-diynes with dihydrosilanes, which enables the facile preparation of Si-stereogenic enynes and an enyne-linked chiral polymer (polyenyne) in good yields and excellent ees (up to >99%) by desymmetrization. The unusual stereoselectivity in this reaction is achieved by precisely controlling the steric hindrance and electronic effect of the newly developed chiral ligands, resulting in a wide range of chiral silanes and a Si-containing polymer bearing a Si-stereogenic center which is otherwise difficult to access. The key to the high enantioselectivity relies on catalyst aggregation-induced non-covalent interaction, which exerts a remarkably positive influence on the Si-H bond activation and enhancement of enantioselectivity, in which the palladium/P-ligand complex was proved to be air-stable and moisture-insensitive in this reaction., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Organosilicon compounds are important reagents and synthetic intermediates that play a key role in the construction of new materials and complex products. Here we show a highly diastereoselective rhodium-catalyzed cycloisomerization of 1,6-dienes, in which the use of (EtO) 3 SiH accelerates the intramolecular cyclization reaction to afford a novel spiro-fused succinimide and pyrazolone derivatives in moderate to excellent yields as a single diastereoisomer. The proposed mechanism involves an active Rh-H species from the hydrosilane that is the H-donor in this spiro-type cycloisomerization reaction., (© 2021 Wiley-VCH GmbH.)

Objective: The study aims to analyze the effectiveness of bevacizumab in addressing the complications associated with gynecological cancers and evaluates effective treatments for various gynecological cancers., Methods: The study follows a systematic review approach that has been implemented to analyze the qualitative published data from previous studies. Studies related with the trials of angiogenesis and bevacizumab were selected in the review., Results: In general, the management of gynecological cancers include chemotherapy, surgery and radiation therapy. Results suggest bevacizumab as an effective treatment modality for cervical and several other cancers. Overall, bevacizumab showed promising results in improving the overall survival rate of gynecological cancer patients through the combination of bevacizumab with other chemotherapeutic agents., Conclusion: Bevacizumab possess less documented adverse effects when compared to other chemotherapeutic agents. The manifestation and severity of adverse effects reported varied according to the chemotherapeutic agent(s) that were used with bevacizumab in combination therapy. Overall, bevacizumab effectively improved the survival rate in patients with several gynaecological cancers., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

This series details two cases of benign pneumatosis intestinalis (PI) in patients post-lung transplant, which were discovered incidentally on routine surveillance chest radiographs during ambulatory clinic visits. Both patients had uneventful post-transplant recovery and were asymptomatic at presentation. The patients were admitted for observation. Contrast-enhanced abdominal CT scans confirmed the plain film findings. Both cases were managed conservatively with bowel rest, intravenous hydration and serial abdominal examinations. The patients had unremarkable hospital courses and were both discharged in good condition. Our current understanding of benign PI in patients post-transplant is limited to a few case series and case reports. Greater awareness of this entity may decrease unnecessary invasive procedures and improve management of these patients., (2015 BMJ Publishing Group Ltd.)

Objective: The effect of miR-449 and miR-34 on the growth, cell cycle and target gene expressions of ovarian cancer cell line SKOV3 and SKOV3-ipl was discussed., Method: Real-time quantitative reverse transcription PCR was employed to detect the expressions of miR-449a/b and miR-34b, c in SKOV3 and SKOV3-ipl cells. The two miRNAs were successfully expressed in SKOV3-ipl cells by transfection. The variations in cell growth rate and cell cycle were determined by MTS assay and flow cytometry, respectively. The expressions of cell cycle-related proteins were detected by Western Blot., Results: miR-449b and miR-34c induced the decline of the adhesiveness of SKOV3-ipl cells by 20%-30%. The number of cells arrested in G1-phase increased and the number of cells arrested in S-phase decreased significantly. The cell cycle-related proteins CDK6 and CDC254 were downregulated. miR-449b caused the expression of CDK6 and CDC25A to decrease. After the co-transfection with miR-449b and miR-34c, the relevant proteins were downregulated more significantly. The expressions of CDK6, CDC25A and cyclin A were decreased significantly., Conclusion: miR-449b and miR-34c can induce cell cycle arrest in SKOV3-ipl cells and the downregulation of CDK6, CDC25A and cyclin A.

Tenodesis of the long head of the biceps (LHB) is a frequently performed procedure during shoulder arthroscopy for the treatment of degenerative, traumatic, or inflammatory lesions of the LHB tendon. Arthroscopic techniques for LHB tenodesis using knotless screw techniques offer the advantage of circumventing the need for arthroscopic knot tying. In 2012 Song and Williams described a novel tenodesis technique that does not require any knot-tying procedures by using a knotless anchor. However, a single-anchor configuration may not offer adequate stabilization of the LHB tendon. Therefore we propose a modified method that uses a double knotless anchor that offers advantages over the single knotless anchor, such as an increase in the contact area between the tendon and bone to facilitate tendon-to-bone healing and strengthening of the tenodesis construct.

Unlabelled: There are several options for LHB tenodesis; yet, there is no standard of care. This technical note describes an extramedullary all-suture anchor technique for LHB tenodesis that is similar to the extramedullary cortical button technique. The LHB tenodesis is performed by using the Y-Knot (1.3-mm; ConMed Linvatec, Largo, FL).The biceps tenotomy is completed arthroscopically, and a standard subpectoral approach is used for the tenodesis. A reamer is first used to drill through the anterior cortex of the humerus; subsequently, a 1.3-mm drill bit is used to drill through the posterior cortex. The Y-Knot anchor is passed through the bone tunnel and secured on the posterior cortical bone. A modified rolling hitch suture is placed 10 mm distal to the end of the LHB tendon by using one suture limb of the Y-Knot anchor. The other suture limb is pulled to shuttle the LHB tendon into the humerus, and the construct is fixed by tying down one limb to the other. This technical note describes an alternative method for subpectoral biceps tenodesis and uses a small drill hole, conserves bone, and minimizes trauma to the tendon., Level of Evidence: V.

AIRE (autoimmune regulator) promotes the establishment of self-tolerance by regulating gene expression in the thymus. Mutations in AIRE lead to an autoimmune disease, APECED. Here we have identified PIAS proteins as novel AIRE interaction partners. Although PIAS proteins function as E3 SUMO ligases, AIRE is not sumoylated. We expressed AIRE, wt PIAS1, and PIAS1 mutants with deleted SP-RING domain or SUMO interaction motif (SIM) in different cell lines and demonstrate that AIRE and PIAS1 localize to adjacent nuclear bodies (NBs). The expression of AIRE enhances the formation of PIAS1 NBs. The ability of PIAS1 to localize into NBs and interconnect with AIRE is neither dependent on the SP-RING domain nor the SIM. Further, we show that PIAS1 is able to attract AIRE into SUMO1-containing complexes and that the process is dependent on the SIM of PIAS1. PIAS1 and AIRE concurrently activate the human insulin promoter, a known target gene of AIRE, and the SP-RING is required for this activation. Moreover, AIRE represses and PIAS1 activates the CSTB promoter, used as a model for a housekeeping promoter, and both the SP-RING and SIM are needed for its activation by PIAS1. Collectively, our data suggest that AIRE and PIAS1 interact functionally to regulate the activities of the target genes of AIRE.

By using three strains with different number of B chromosome (1-2Bs, 0B, > 2Bs) on the same genetic background, the effect of B chromosome on the reproduction of Drosophila albomicans was studied. Comparison of net reproduction and sex ratio among three strains showed that Bs has significantly effect on flies' net reproduction. The net reproduction of flies with 1-2Bs, 0B, > 2Bs is 196, 157, 147, respectively. Significant difference among three strains exists in the early stage of reproduction. The sex ratios of three strains are all close to 1:1, no significant difference was observed. The results indicated that lower dose of Bs enhances the flies' reproduction and fitness, while higher dose of Bs slightly reduces flies reproduction and fitness. These results lend the first strong support to the heterotic model.

The technique of mtDNA restriction fragments length polymorphism (RFLP) was used to survey the population structure of D. albomicans. Remarkable mtDNA polymorphism has been observed in D. albomicans populations. A total of 34 nucleomorphs were detected from 82 isofemale lines assayed by only 8 restriction enzymes. The cause and the effect of this phenomenon were discussed. As a result, it is suggested that a mechanism which maintains mtDNA diversity exists in this fly, and that the high intra-populational polymorphism could numerically conceal the extent of differentiation between populations. In addition, on the base of restriction maps, it was found that the mtDNA molecule of D. albomicans might be impacted by the selection pressure during its evolution process both on the nucleotide composition and on the functional regions.