16 research outputs found

    Pre-M Phase-promoting Factor Associates with Annulate Lamellae in Xenopus Oocytes and Egg Extracts

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    We have used complementary biochemical and in vivo approaches to study the compartmentalization of M phase-promoting factor (MPF) in prophase Xenopus eggs and oocytes. We first examined the distribution of MPF (Cdc2/CyclinB2) and membranous organelles in high-speed extracts of Xenopus eggs made during mitotic prophase. These extracts were found to lack mitochondria, Golgi membranes, and most endoplasmic reticulum (ER) but to contain the bulk of the pre-MPF pool. This pre-MPF could be pelleted by further centrifugation along with components necessary to activate it. On activation, Cdc2/CyclinB2 moved into the soluble fraction. Electron microscopy and Western blot analysis showed that the pre-MPF pellet contained a specific ER subdomain comprising "annulate lamellae" (AL): stacked ER membranes highly enriched in nuclear pores. Colocalization of pre-MPF with AL was demonstrated by anti-CyclinB2 immunofluorescence in prophase oocytes, in which AL are positioned close to the vegetal surface. Green fluorescent protein-CyclinB2 expressed in oocytes also localized at AL. These data suggest that inactive MPF associates with nuclear envelope components just before activation. This association may explain why nuclei and centrosomes stimulate MPF activation and provide a mechanism for targeting of MPF to some of its key substrates

    Human Resource Flexibility as a Mediating Variable Between High Performance Work Systems and Performance

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    Much of the human resource management literature has demonstrated the impact of high performance work systems (HPWS) on organizational performance. A new generation of studies is emerging in this literature that recommends the inclusion of mediating variables between HPWS and organizational performance. The increasing rate of dynamism in competitive environments suggests that measures of employee adaptability should be included as a mechanism that may explain the relevance of HPWS to firm competitiveness. On a sample of 226 Spanish firms, the study’s results confirm that HPWS influences performance through its impact on the firm’s human resource (HR) flexibility

    Video assisted esophagectomy for esophageal cancer

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    Video assisted surgery for esophageal cancer is an advanced surgical technique. It is being adopted with a concept of minimally invasive surgery. Since there are several options of the operative procedure for thoracic esophageal cancer, there are several laparoscopic approaches. The first VATS esophagectomy through a right thoracoscopic approach and the first transhiatal esophagectomy were reported in early 1990's. Mediastinoscope-assisted esophagectomy is also reported as a substitute of the blunt dissection of the esophagus. Moreover, video assisted Ivor-Lewis esophagectomy by right thoracotomy with intrathoracic anastomosis has also been tried. Furthermore, laparoscopic gastric mobilization and gastroplasty is also widely accepted as a substitution for open laparotomy. This article serves to review the literature on laparoscopic approaches for esophageal cancer
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