Recruitment of katanin p60 by phosphorylated NDEL1, an LIS1 interacting protein, is essential for mitotic cell division and neuronal migration

LIS1 is mutated in the human neuronal migration defect lissencephaly and along with NDEL1 (formerly NUDEL) participates in the regulation of cytoplasmic dynein function during neuronal development. Targeted disruption of Ndel1 suggested that NDEL1 could have other molecular targets that regulate microtubule organization for proper neuronal migration. To further understanding the molecular mechanism of LIS1 and lissencephaly, we identified the katanin p60 microtubule-severing protein as an additional molecular target of NDEL1. We demonstrate that phosphorylation of NDEL1 by Cdk5 facilitates interaction between NDEL1 and p60, suggesting that P-NDEL1 regulates the distribution of katanin p60. Abnormal accumulation of p60 in nucleus of Ndel1 null mutants supports an essential role of NDEL1 in p60 regulation. Complete loss of NDEL1 or expression of dominant negative mutants of p60 in migrating neurons results in defective migration and elongation of nuclear-centrosomal distance. Our results suggest that NDEL1 is essential for mitotic cell division and neuronal migration not only via regulation of cytoplasmic dynein function but also by modulation of katanin p60 localization and function.     

Pulmonary synovial sarcoma with polypoid endobronchial growth: a case report, immunohistochemical and cytogenetic study

A rare case of primary pulmonary synovial sarcoma with polypoid endobronchial growth in a 42-year-old Japanese woman is described. Left upper sleeve lobectomy was performed for the polypoid tumor measuring 2.5 cm in the left major bronchus and the patient was treated with adjuvant chemotherapy. Three years later, a recurrent tumor was discovered. Microscopically, this tumor was characterized by a proliferation of oval to spindle-shaped cells arranged in sheets and fascicles and covered by the thin normal bronchial epithelium. Immunohistochemically, tumor cells were positive for vimentin, and focally positive for pancytokeratin recognized by AE1/AE3, cytokeratin 7 and epithelial membrane antigen. A chimera gene, SYT-SSX1, was detected. Recently, primary pulmonary synovial sarcoma is an increasingly recognized clinical entity; however, most of these tumors present as a parenchymal mass. The present case is a unique example of primary synovial sarcoma of endobronchial polypoid type. This case suggests that pulmonary synovial sarcoma might originate from bronchial submucosal stromal tissue.     

Flavonoids such as luteolin, fisetin and apigenin are inhibitors of interleukin-4 and interleukin-13 production by activated human basophils

BACKGROUND: We have previously shown that fisetin, a flavonol, inhibits IL-4 and IL-13 synthesis by allergen- or anti-IgE-antibody-stimulated basophils. This time, we investigated the inhibition of IL-4 and IL-13 production by basophils by other flavonoids and attempted to determine the fundamental structure of flavonoids related to inhibition. We additionally investigated whether flavonoids suppress leukotriene C4 synthesis by basophils and IL-4 synthesis by T cells in response to anti-CD3 antibody. METHODS: Highly purified peripheral basophils were stimulated for 12 h with anti-IgE antibody alone or anti-IgE antibody plus IL-3 in the presence of various concentrations of 18 different kinds of flavones and flavonols. IL-4 and IL-13 concentrations in the supernatants were then measured. Leukotriene C4 synthesis was also measured after basophils were stimulated for 1 h in the presence of flavonoids. Regarding the inhibitory activity of flavonoids on IL-4 synthesis by T cells, peripheral blood mononuclear cells were cultured with flavonoids in anti-CD3-antibody-bound plates for 2 days. RESULTS: Luteolin, fisetin and apigenin were found to be the strongest inhibitors of both IL-4 and IL-13 production by basophils but did not affect leukotriene C4 synthesis. At higher concentrations, these flavonoids suppressed IL-4 production by T cells. Based on a hierarchy of inhibitory activity, the basic structure for IL-4 inhibition by basophils was determined. CONCLUSIONS: Due to the inhibitory activity of flavonoids on IL-4 and IL-13 synthesis, it can be expected that the intake of flavonoids, depending on the quantity and quality, may ameliorate allergic symptoms or prevent the onset of allergic diseases.     

Immunocytochemical characteristics of human osteosarcoma cell line HS-Os-1: possible implication in apoptotic resistance against irradiation

In our previous study, we examined reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy irradiation. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of the hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation. In the succeeding study, we examined radiation-induced ROS formation, oxidative DNA damage, early apoptotic changes, and mitochondrial membrane dysfunction in the human osteosarcoma cell line HS-Os-1. We found that ROS formation and oxidative DNA damage were actually scarcely seen after irradiation of up to 30 Gy in these cells, that mitochondrial membrane potential was preserved, and that apoptotic changes were not demonstrated despite the relatively high-dose irradiation of 30 Gy. In the present study, we examined the immunocytochemical characteristics of the apoptotic-resistance of the HS-Os-1 cell line against irradiation in order to clarify its possible implications regarding radiosensitivity. The results showed that these cells lack P53 and Bax protein expression, and strong peroxidase activity was confirmed in the nuclei of the cells. Moreover, SODII (manganese superoxide dismutase II) protein expression was gradually increased in spite of irradiation of up to 30 Gy. Therefore, it is concluded that HS-Os-1 cells are originally apoptotic-resistant and that the cells possess a strong ability to scavenge for free radicals. To convert these cells to a state of apoptotic-susceptibility, a powerful oxidant such as hydrogen peroxide might exert such an effect in terms of the production of hydroxyl radicals in lysosomes in the cells as shown in our previous studies. The origin of the radioresistance of the human osteosarcoma cell line HS-Os-1 is considered to to be low degree of ROS formation following irradiation, reflecting the strong scavenging ability of these cells for free radicals including hydroxyl radicals.     

M pathway and areas 44 and 45 are involved in stereoscopic recognition based on binocular disparity

We characterized the visual pathways involved in the stereoscopic recognition of the random dot stereogram based on the binocular disparity employing a functional magnetic resonance imaging (fMRI). The V2, V3, V4, V5, intraparietal sulcus (IPS) and the superior temporal sulcus (STS) were significantly activated during the binocular stereopsis, but the inferotemporal gyrus (ITG) was not activated. Thus a human M pathway may be part of a network involved in the stereoscopic processing based on the binocular disparity. It is intriguing that areas 44 (Broca's area) and 45 in the left hemisphere were also active during the binocular stereopsis. However, it was reported that these regions were inactive during the monocular stereopsis. To separate the specific responses directly caused by the stereoscopic recognition process from the nonspecific ones caused by the memory load or the intention, we designed a novel frequency labeled tasks (FLT) sequence. The functional MRI using the FLT indicated that the activation of areas 44 and 45 is correlated with the stereoscopic recognition based on the binocular disparity but not with the intention artifacts, suggesting that areas 44 and 45 play an essential role in the binocular disparity.     

Comparative anatomical study of the kidney position in amniotes using the origin of the renal artery as a landmark

The anatomical relationship between the kidney position and its arterial supply was investigated in 21 mammals, 1 bird, and 3 reptiles (n = 1 for each species) and in 43 human cadavers. The following observations were made. (1) Although the right kidney was located caudal to the left kidney in 29 out of 43 human cadavers (67.4%), the origin of the right renal artery from the aorta was located cranial to the origin of the left renal artery in 36 human cadavers (83.7%). Therefore, the relative positions of the kidneys do not correspond with the relative origins of the renal arteries in humans. (2) Among the mammals that were examined, the position of the kidney and the branching level of the renal artery on the right side were usually cranial to those on the left side. (3) In the bird and most reptiles that were examined, kidneys were typically located in the pelvic region and were supplied by segmental arterial branches. These results suggest that the right kidney and its arterial supply are generally located cranial to the left kidney in phylogeny of mammals. While the presence of a human accessory renal artery in 9 out of 86 sides (10.5%) and a cranial origin of the left renal artery relative to the right renal artery in 7 out of 43 cadavers (16.3%), shows some variation in the arterial supply to the kidneys, the origin of the renal arteries can generally be used as phylogenetic landmarks indicating the relative positions of the kidneys. Hence, from an ontological perspective, the human right kidney may be initially situated cranial to the left kidney during the early stages of development. Thereafter, the human right kidney may shift downwards secondary.     

Formalin-induced minor tremor response as an indicator of pain

Formalin which was said to produce prolonged pain and inflammation was injected subcutaneously into the back of guinea pigs, and minor tremor pain response (MTP-response) was measured using the MT-pick up, integrator and digital volt meter. The MTP-response curve showed a biphasic pattern. Immediately after injection, the MTP-response curve showed a significant peak which lasted for about 2 min (the first phase) and subsequently dipped rapidly, and after 5 min, it began to rise slowly again and had a peak at 30 min (the second phase). Morphine (6 mg/kg, s.c.) inhibited completely the first and second phases. Levallorphan (1.2 mg/kg), however, reversed the inhibitory effect of morphine at the first phase, but not at the second phase. Aspirin (200 mg/kg, i.p.), aminopyrine (100 mg/kg, s.c.) and pentazocine (5 mg-10 mg/kg, s.c.) inhibited significantly the formalin-induced MTP-response at both phases. Pyridinol carbamate (200 mg/kg, i.p.) and hydrocortisone (25 mg/kg, i.p.) had no effect on the MTP-response at the first phase, but inhibited it at the second phase. There was a parallelism between the time course of the vascular permeability induced by formalin and that of the second phase of MTP-response. From these results, it is suggested that the first phase of MTP-response is derived from the direct effect of formalin on free nerve endings, while the second phase is derived from the inflammation. Since two kinds of pain features were differentiated in this method, the relationships with so-called "immediate pain" and "delayed pain" were discussed. Furthermore, this method can be utilized to assess pain and the action of analgesics objectively and quantitatively.