LiOtBu-Promoted trans-Stereoselective and ß-Regioselective Hydroboration of Propargyl Alcohols.

A convenient and efficient trans-stereoselective and ß-regioselective hydroboration of propargyl alcohols was achieved simply with LiOtBu as the base and (Bpin)2 as the boron reagent in dimethyl sulfoxide at room temperature. Both terminal and internal propargyl alcohols with diverse structures and functional groups underwent the transformation smoothly to produce ß-Bpin-substituted (E)-allylic alcohols, of which the synthetic potentials were demonstrated by the downstream conversions of boronate, alkenyl, and hydroxyl groups.

Longitudinal association between the timing of adiposity peak and rebound and overweight at seven years of age.

BACKGROUND: The timing of adiposity peak (AP) or adiposity rebound (AR) is a determinant of overweight or obesity in adolescence and adulthood. However, limited studies have reported the association in young school-age children. We aimed to evaluate this association and explore the role of health behaviours in it. METHODS: Routinely collected, sequential, anthropometric data from the 1st to 80th months of age were used to estimate AP and AR timings in 2330 children born in Shanghai between 2010 and 2013. Multivariate regression analyses were applied to identify the associations between the AP or AR timings and the risk of developing overweight or obesity in first-grade school children. The roles of health behaviours, including dietary patterns, physical activity level, sleep and snacking habits, and screen time, were also evaluated. RESULTS: Children with a late AP or an early AR were at higher risk of overweight but not obesity or central obesity in their first grade. A high physical activity level was associated with a lower risk of having overweight in children with a late AP, and limited screen time was associated with a decreased risk of having overweight or obesity in children with an early AR. The absence of a late-night snacking habit in children with a non-early AR indicated a decreased risk of having overweight. However, this association was not observed among children with an early AR. CONCLUSION: The timings of AP and AR are tied to overweight in middle childhood. Prevention strategies are suggested to move forward to control late AP and early AR.

microRNA-33a prevents epithelial-mesenchymal transition, invasion, and metastasis of gastric cancer cells through the Snail/Slug pathway.

Invasion and metastasis are responsible for the majority of deaths in gastric cancer (GC). microRNA-33a (miR-33a) might function as a tumor suppressor in multiple cancers. Here, we describe the regulation and function of miR-33a in GC and mechanisms involved in epithelial-mesenchymal transition (EMT) and metastasis. First, GC tissues and adjacent normal tissues were collected. miR-33a upregulation or SNAI2 depletion on GC cells were introduced to assess the detailed regulatory mechanism of them. We assessed the expression of miR-33a, SNAI2, Snail/Slug signaling pathway-related genes, and EMT-related markers in GC tissues and cells. miR-33a distribution in GC tissues and adjacent normal tissues was measured. Cell proliferation, migration and invasion, and cell cycle distribution were assessed. In nude mice, GC tumor growth and lymph node metastasis were observed. Furthermore, the predicative value of miR-33a in the prognosis of GC patients was evaluated. The obtained results indicated that lowly expressed miR-33a, highly expressed SNAI2, activated Snail/Slug, and increased EMT were identified in GC tissues. miR-33a was located mainly in the cytoplasm. miR-33a targeted and negatively regulated SNAI2. MKN-45 and MKN-28 cell lines were selected for in vitro experiments. Upregulated miR-33a expression or siRNA-mediated silencing of SNAI2 suppressed the activation of Snail/Slug, whereby GC cell proliferation, invasion and migration, EMT, tumor growth, and lymph node metastasis were inhibited. High expression of miR-33a was a protective factor influencing the prognosis of GC. This study suggests that miR-33a inhibited EMT, invasion, and metastasis of GC through the Snail/Slug signaling pathway by modulating SNAI2 expression.NEW & NOTEWORTHY miR-33a targets and inhibits the expression of SNAI2, overexpression of SNAI2 activates the Snail/Slug signaling pathway, the Snail/Slug signaling pathway promotes GC cell proliferation, invasion, and metastasis, and overexpression of miR-33a inhibits cell proliferation, invasion, and metastasis. This study provides a new therapeutic target for the treatment of GC.