Plasmodium induced by SU6656, an Src family kinase inhibitor,is accompanied by a contractile ring defect

We have shown that SU6656, a potent Src family kinase inhibitor, has the ability to induce multinucleation at a high frequency in diverse cells: rat skin fibroblasts, bone marrow adherent cells, 5F9A mesenchymal stem cell‐like clones, 2C5 tracheal epithelial cells and MDCK epithelial cells from dog kidney. To gain insight into the mechanism of multinucleation, we observed the process by time‐lapse and confocal microscopy. These multinuclei generally seem to exist independently in one cell without any connections with each other. By time‐lapse microscopy, multinucleated cells were found to be formed through the mechanism of plasmodium: karyokinesis without cytokinesis. The observation of EGFP‐actin transfected cells by time‐lapse confocal laser scanning microscopy suggested that plasmodium occurred with deficient contractile ring formation. Although we examined the differentiation of these cells, the multinucleated cells could not be categorized into any type of cell in vivo known to exhibit multinuclei. Copyright © 2011 John Wiley & Sons, Ltd.     

Determining homologous recombination deficiency scores with whole exome sequencing and their association with responses to neoadjuvant chemotherapy in breast cancer

Recent studies demonstrated that homologous repair deficiency (HRD) score is a useful marker for response to poly (ADP-ribose) polymerase inhibitors or platinum-based chemotherapy. We determined HRD scores and elucidated the clinicopathologic characteristics of HRD-high tumors and their response to non-platinum-based chemotherapy. Primary breast cancer patients (n = 120) were pre-operatively treated with paclitaxel followed by 5-fluorouracil/epirubicin/cyclophosphamide (P-FEC). Germline and somatic homologous recombination related gene mutations (gHRRm and sHRRm, respectively) and HRD scores were analyzed using whole exome sequencing (WES) in tumor tissues obtained before chemotherapy. Of 120 tumors, 30 were determined to be HRD-high tumors, significantly associated with high Ki-67 (P = 0.014), ER negativity (P = 0.007), and PR negativity (P = 0.021). Triple-negative cancers showed significantly higher HRD scores than the luminal, luminal-HER2, and HER2 subtypes (P = 0.023, 0.016, and 0.033, respectively). HRD scores were significantly higher in tumors with gHRRm than in those with sHRRm (P = 0.002) or wild-type HRR genes (P = 1.44e-4), but no significant difference was found in HRD scores between tumors with sHRRm and wild-type HRR genes (P = 0.206). HRD-high tumors had significantly (P = 0.003) higher pCR rates and higher near-pCR rates (P = 0.049) compared with those of the HRD-low tumors in all tumors and the luminal subtype, respectively. HRD-high tumors were associated with aggressive phenotypes and gHRRm, but not sHRRm. Our findings suggested that HRD scores might be useful in predicting response to P-FEC in the luminal subtype.     

Leukocyte adhesion molecule expression during intense resistance exercise

We hypothesized that expression of L-selectinand very late antigen-4 (VLA-4) integrin adhesionmolecules would influence cell type-specific redistribution duringexercise. Women subjects performed six sets of 10-repetition maximumsquats. L-selectin and VLA-4 integrin were measured by using flowcytometry pre- and postexercise on peripheral blood neutrophils andlymphocytes (n = 29 subjects) andlymphocyte subsets (n = 70 subjects),respectively. Neutrophil concentration increased 41.8%(P < 0.001), whereas the percentexpressing L-selectin was unchanged (79%). Lymphocyte concentrationincreased 61.8% (P < 0.001). Thepercent of T cells expressing L-selectin decreased from 73.5 ± 8.9 to 68.2 ± 11.4% (P < 0.001); the combined population of natural killer and B cells expressing L-selectin decreased from 80.4 ± 22.5 to 62.7 ± 25.8% (P < 0.001).VLA-4 integrin was expressed by nearly all lymphocytes both pre- andpostexercise. The proportional decrease in L-selectin positive cellscould have resulted from 1) sheddingof L-selectin, 2) selective entry ofL-selectin-negative subsets, or 3)selective removal of L-selectin-positive subsets.

     

A marking-and-recapture analysis of the adult population of a phytophagous lady-beetle,Epilachna sparsa orientalis

A marking-and-recapture study of a population of overwintered adults of Epilachna sparsa orientalis was carried out in a small farm containing potatoes and egg-plants. The experiment involved a single release and five recapture samplings during May–June. The data were analysed byLeslie's re-recapture method. Assumption of randomness of sampling proved to be well satisfied. Survival rate of the overwintered adult population was maintained as high as 90 per cent per week or more until early June, and then it declined rapidly towards the end of June. Initially overwintered adults exclusively lived on potato plants, but half of the population alive in mid June migrated to nearby egg-plants. Emigration out of the experimental field, however, seemed not to be occurring. Recapture data of marked individuals in the potato field indicate that majority of the individuals stayed within a radius of 3 m, at least for 2 weeks. Similar data taken from another field also suggest that their mobility was far restricted as compared with random movement within the field. Some comparisons were made between the population behaviours of overwintered adults of E. sparsa orientalis and E. vigintioctomaculata.     

Female mimicry in a freshwater goby <Emphasis Type="Italic">Rhinogobius</Emphasis> sp. OR

 We found female-mimic males in a freshwater goby, Rhinogobius sp. OR, from Kamo River, Ehime, Japan. Of 171 adult males collected, three had a female appearace. A discriminant analysis showed that they had a spectrum of morphology from a wholly female morph, through a neutral morph, to a somewhat malelike morph. These three males made an extremely higher gametic investment than did the normal males, suggesting that they have the potential for sneaking fertilizations. Among Rhinogobius species, female mimicry might be more common than previously known. Received: September 24, 2002 / Revised: January 23, 2003 / Accepted: February 4, 2003     

Distribution of calcium-ATPase in developing teeth of embryonic American alligators (Alligator mississippiensis)

Light microscopic and ultrastructural observations were carried out to evaluate the cell morphology and histochemistry (calcium-ATPase activity) of developing teeth in embryonic American alligators (Alligator mississippiensis). Ca-ATPase activity was observed in the distal and lateral cell membranes, rough endoplasmic reticulum (rER), mitochondria, vacuoles, and other organelles of the ameloblast, but only in the distal cell membrane and process of the odontoblast. Enzyme activity in the ameloblasts increased gradually during development. These sites of enzyme activity are related to mineralization of the enamel layer, similar to that in mammalian tooth development. Alligator teeth are heavily mineralized like mammalian teeth; however, alligator ameloblasts have undeveloped distal processes during mineralization in contrast to mammalian ameloblasts in which Tomes' processes are found near the distal portion of ameloblasts at maturation stage. The localization of intense enzyme activity in the distal and lateral ameloblast cell membrane suggests that these regions are the site of accumulation of calcium as enamel differentiates in the developing tooth. © 1993 Wiley-Liss, Inc.     

Paraquat Resistant Tobacco Calluses with Enhanced Superoxide Dismutase Activity

Seven paraquat resistant calluses of tobacco (Nicotiana tabacumL. cv. Samsun) were obtained by three successive screeningsof protoplast-derived calluses on a paraquat containing medium.Superoxide dismutase (SOD) activity of the resistant calluseswas 14- to 159-fold that of the leaf cells on protein basis.Paraquat-resistant calluses, however, showed little increasein catalase and peroxidase activities. More than 90% of SODactivity in the resistant calluses was inhibited by KCN, aswas the SOD activity in leaves, indicating that the major SODin the callus appears to be the Cu, Zn containing enzyme. Thecallus cells, however, expressed the immunologically distinguishedSOD isozyme from the enzyme in the leaves. (Received April 23, 1984; Accepted August 6, 1984)