In the fission yeast Schizosaccharomyces pombe, interphase microtubules (MTs) position the nucleus [1, 2], which in turn positions the cell-division plane [1, 3]. It is unclear how the spindle orients, with respect to the predetermined division plane, to ensure that the chromosomes are segregated across this plane. It has been proposed that, during prometaphase, the astral MT interaction with t...

gamma-Tubulin is a conserved component of microtubule-organizing centers and is thought to be involved in microtubule nucleation. A recently discovered Saccharomyces cerevisiae gene (TUB4) encodes a tubulin that is related to, but divergent from, gamma-tubulins. TUB4 is essential for cell viability, and epitope-tagged Tub4 protein (Tub4p) is localized to the spindle pole body (Sobel, S.G., and ...

The spindle checkpoint monitors mitotic spindle integrity and the attachment of kinetochores to the spindle. Upon sensing a defect the checkpoint blocks cell cycle progression and thereby prevents chromosome missegregation. Previous studies in budding yeast show that the activated spindle checkpoint inhibits the onset of anaphase by an unknown mechanism. One possible target of the spindle check...

In the budding yeast Saccharomyces cerevisiae, the mitotic spindle must align along the mother-bud axis to accurately partition the sister chromatids into daughter cells. Previous studies showed that spindle orientation required both astral microtubules and the actin cytoskeleton. We now report that maintenance of correct spindle orientation does not depend on F-actin during G2/M phase of the c...

Spindle cell rhabdomyosarcoma is a rare variant of embryonal rhabdomyosarcoma that affects young males and most commonly involves the paratesticular region. We report a case of paratesticular spindle cell rhabdomyosarcoma in a 14-year-old boy, who presented with a painless scrotal mass. Left inguinal orchidectomy was performed. Histopathological and immunohistochemical examination of the mass r...

pseudoinclusions are sometimes evident and mild nuclear pleomorphism is typical. Mitoses are either absent or extremely infrequent. By definition dendritic cells are said not to be seen in this lesion. The growth pattern often presents a plexiform appearance, fascicles of nevus cells following the dermal appendages and neurovascular bundles. Perineural or endoneural extension is a very common f...

Background: Epithelioid hemangioendothelioma is a rare tumour whose prognosis ranges from benign form similar to hemangioma to aggressive tumors like angiosarcoma. Its localization in the rib is very rare and less than 10 cases of costal localized forms have been reported in the literature. The authors describe another case of costal epithelioid hemangioendothelioma illustrated by microscopic f...

Coordinated cell polarization and mitotic spindle orientation are thought to be important for epithelial morphogenesis. Whether spindle orientation is indeed linked to epithelial morphogenesis and how it is controlled at the molecular level is still unknown. Here, we show that the NuMA- and Galpha-binding protein LGN is required for directing spindle orientation during cystogenesis of MDCK cell...

A 19-year-old woman was referred to our hospital because of bilateral multiple nodular shadows on the chest radiograph. She complained of no symptoms. The pulmonary lesions were diagnosed pathologically as epithelioid hemangioendothelioma. She has been followed without treatment for more than 10 years. Among all lesions, only two pulmonary nodules enlarged slightly, and it is interesting that o...

Epithelioid hemangioendothelioma is a rare vascular tumor, which occurs in the lung, liver, bone, and soft tissue. Hypertrophic osteoarthropathy is a syndrome characterized by subperiosteal new bone formation, joint effusion and clubbing, and may be associated with cyanotic heart disease, chronic pulmonary disease, liver disease, and other miscellaneous diseases. The activation of endothelium a...