Observation of a large reaction cross section in the drip-line nucleus 22C

Reaction cross sections (sigma(R)) for 19C, 20C and the drip-line nucleus 22C on a liquid hydrogen target have been measured at around 40A MeV by a transmission method. A large enhancement of sigma(R) for 22C compared to those for neighboring C isotopes was observed. Using a finite-range Glauber calculation under an optical-limit approximation the rms matter radius of 22C was deduced to be 5.4+/-0.9 fm. It does not follow the systematic behavior of radii in carbon isotopes with N < or = 14, suggesting a neutron halo. It was found by an analysis based on a few-body Glauber calculation that the two-valence neutrons in 22C preferentially occupy the 1s(1/2) orbital.

Reactive oxygen generated by NADPH oxidase 1 (Nox1) contributes to cell invasion by regulating matrix metalloprotease-9 production and cell migration

A mediating role of the reactive oxygen species-generating enzyme Nox1 has been suggested for Ras oncogene transformation phenotypes including anchorage-independent cell growth, augmented angiogenesis, and tumorigenesis. However, little is known about whether Nox1 signaling regulates cell invasiveness. Here, we report that the cell invasion activity was augmented in K-Ras-transformed normal rat kidney cells and attenuated by transfection of Nox1 small interference RNAs (siRNAs) into the cells. Diphenyleneiodonium (DPI) or Nox1 siRNAs blocked up-regulation of matrix metalloprotease-9 at both protein and mRNA levels in K-Ras-transformed normal rat kidney cells. Furthermore, DPI and Nox1 siRNAs inhibited the activation of IKKalpha kinase and the degradation of IkappaB alpha, suppressing the NFkappaB-dependent matrix metalloprotease-9 promoter activity. Additionally, epidermal growth factor-stimulated migration of CaCO-2 cells was abolished by DPI and Nox1 siRNAs, indicating the requirement of Nox1 activity for the motogenic effect of epidermal growth factor. This Nox1 action was mediated by down-regulation of the Rho activity through the low molecular weight protein-tyrosine phosphatase-p190RhoGAP-dependent mechanism. Taken together, our findings define a mediating role of Nox1-generated reactive oxygen species in cell invasion processes, most notably metalloprotease production and cell motile activity.

Protein kinase C beta inhibitor prevents diabetic peripheral neuropathy, but not histopathological abnormalities of retina in Spontaneously Diabetic Torii rat

Spontaneously Diabetic Torii (SDT) rat shows severe ocular complications such as tractional retinal detachment. In the present study, effect of protein kinase C beta (PKCbeta) inhibitor JTT-010 was evaluated to clarify the involvement of PKCbeta in complications of SDT rat. SDT rats were administered JTT-010 (10 or 50 mg/kg/day) for 48 weeks. SDT rats showed delayed oscillatory potentials in electroretinogram. Delayed motor nerve conduction velocity, decreased coefficients of variation of R-R intervals in electrocardiogram and thermal hypoalgesia were also observed. These functional disorders were prevented by administration of JTT-010. Abnormal retinal vascular was formed and the optic disc was protruded in SDT rat; however, JTT-010 did not prevent these hyperglycaemia-induced retinal abnormalities. These findings indicate that PKCbeta is intimately involved in diabetic complications; however, it seems that other factor(s) are primary contributors to histopathological abnormalities in retina. Therefore, PKCbeta inhibitors require concurrent administration of antihyperglycaemic drugs to achieve maximum effect on diabetic complications.

[Chemotherapy for non-small cell lung cancer: split-dose administration of Cisplatin over four consecutive days and Vinorelbine ditartrate]

PURPOSE

At present, combination chemotherapy with Cisplatin (CDDP) and Vinorelbine ditartrate (VNR) is one of the standard regimens for non-small cell lung cancer (NSLC). To avoid renal damage by CDDP, hydration and diuretic are indicated. But elderly/postoperative patients who have reduced lung vessel capacity are a high-risk group for pulmonary edema/right heart failure by hydration. In our hospital, CDDP is administered on four consecutive days without large hydration.

MATERIAL & METHODS

CDDP: 80 mg/m2 (over four consecutive days)without large hydration+VNR: 20 mg/m2 was administered 30 NSLC patients(Stage III A & IV). Serum concentration of CDDP was monitored.

RESULT

Response rate was CR: 0 case; PR: 9 cases; SD: 16 cases; PD: 5 cases. Mean survival time (MST) was 292 days. The efficacy and prognosis are equivalent to a conventional CDDP+VNR regimen. On the other hand, side effects were reduced; neutrocytopenia (> Grade 3): 17%, renal dysfunction (>Grade 1): 17%. Mean serum concentrations of CDDP were accumulated day by day, 0.91 microg/mL(Day 1), 2.44 microg/mL(Day 4), but were all under the toxic threshold(8 microg/mL).

CONCLUSION

Our regimen (CDDP given over four consecutive days without large hydration) may become a regimen for the high-risk patient.

Rapid telomere movement in meiotic prophase is promoted by NDJ1, MPS3, and CSM4 and is modulated by recombination

Haploidization of the genome in meiosis requires that chromosomes be sorted exclusively into pairs stabilized by synaptonemal complexes (SCs) and crossovers. This sorting and pairing is accompanied by active chromosome positioning in meiotic prophase in which telomeres cluster near the spindle pole to form the bouquet before dispersing around the nuclear envelope. We now describe telomere-led rapid prophase movements (RPMs) that frequently exceed 1 microm/s and persist throughout meiotic prophase. Bouquet formation and RPMs depend on NDJ1, MPS3, and a new member of this pathway, CSM4, which encodes a meiosis-specific nuclear envelope protein required specifically for telomere mobility. RPMs initiate independently of recombination but differ quantitatively in mutants that fail to complete recombination, suggesting that RPMs respond to recombination status. Together with recombination defects described for ndj1, our observations suggest that RPMs and SCs balance the disruption and stabilization of recombinational interactions, respectively, to regulate crossing over.

Superselective intra-arterial infusion chemotherapy for stage III/IV squamous cell carcinomas of the oral cavity: Midterm results

PURPOSE

We performed superselective intra-arterial infusion chemotherapy (SIC) according to a protocol in which drug distribution is evaluated by the use of interventional radiology (IVR)-computed tomography (CT) system, and the chemotherapy is combined with medium-dose conformal radiation therapy (CRT). We analyzed retrospectively the factors that affect the midterm survival ratio, including local response, for stage III and IV squamous cell carcinomas of the oral cavity.

MATERIALS AND METHODS

Forty consecutive patients with stage III and IV squamous cell carcinomas of the oral cavity and who had undergone both SIC and CRT were enrolled. A microcatheter was placed in the appropriate feeding artery of the tumor and cisplatin (50mg/body) was infused twice. CRT was administered with a dual-energy (4 and 10 MV) linear accelerator. The total and daily doses delivered were 30 and 2.0 Gy, respectively. Histopathologic effects were classified into five grades: grade 0 or 1 was defined as a poor response, and grade II or higher as a good response. Age, sex, stage, local response to treatment, mode of invasion and lymph node metastasis were analyzed, and differences in the midterm survival ratio were assessed.

RESULTS

The 3-year survival ratio of the 40 cases was 67%. A good local response (III or IV) was achieved in 75% of the cases. The survival ratio of the good local response group was significantly better than that of the poor response group (p=0.04). Mode of invasion (p=0.03) and lymph node metastasis (p=0.01) were also predictive of survival. In the multivariable analysis of survival, however, no variables including good local response (p=0.12), were predictive.

CONCLUSION

Our new protocol improved local response, but it did not contribute to the survival ratio.

Tyrosine kinases Btk and Tec regulate osteoclast differentiation by linking RANK and ITAM signals

Certain autoimmune diseases result in abnormal bone homeostasis, but association of immunodeficiency with bone is poorly understood. Osteoclasts, which derive from bone marrow cells, are under the control of the immune system. Differentiation of osteoclasts is mainly regulated by signaling pathways activated by RANK and immune receptors linked to ITAM-harboring adaptors. However, it is unclear how the two signals merge to cooperate in osteoclast differentiation. Here we report that mice lacking the tyrosine kinases Btk and Tec show severe osteopetrosis caused by a defect in bone resorption. RANK and ITAM signaling results in formation of a Btk(Tec)/BLNK(SLP-76)-containing complex and PLCgamma-mediated activation of an essential calcium signal. Furthermore, Tec kinase inhibition reduces osteoclastic bone resorption in models of osteoporosis and inflammation-induced bone destruction. Thus, this study reveals the importance of the osteoclastogenic signaling complex composed of tyrosine kinases, which may provide the molecular basis for a new therapeutic strategy.

Purification and characterization of a novel esterase (beta-hydroxypalmitate methyl ester hydrolase) and prevention of the expression of virulence by Ralstonia solanacearum

AIMS

To screen novel micro-organisms and enzymes capable of degrading 3-hydroxypalmitic acid methyl ester (3-OH PAME), the quorum-sensing signal molecule (quormone), which regulates the virulence of Ralstonia solanacearum.

METHODS AND RESULTS

Ideonella sp. 0-0013, a betaproteobacterium isolated from soil using the selective-enrichment culture method, was grown on plates containing 3-OH PAME as its main carbon source. beta-Hydroxypalmitate methyl ester hydrolase (betaHPMEH) purified from the supernatant of the Ideonella sp. 0-0013 culture exhibited high hydrolysing activity towards the ester bond of 3-OH PAME and eliminated the 3-OH PAME activity, thereby reducing the virulence of R. solanacearum. An Escherichia coli transformant of the betahpmeh gene expression vector degraded 3-OH PAME, and the crude enzyme from the transformant inhibited in vitro production of the R. solanacearum exopolysaccharide (EPS).

CONCLUSIONS

The ability of betaHPMEH to hydrolyse 3-OH PAME inhibited the production of EPS by the R. solanacearum wild-type strain, indicating that betaHPMEH inhibits the effects of activation of virulence genes. This ability will be potentially useful for pest control of the wilt disease caused by this bacterium.

SIGNIFICANCE AND IMPACT OF THE STUDY

This enzyme is the first protein that has been found to degrade a quormone other than N-acyl homoserine lactone.

Biarticular leg muscles and links to running economy

Relationships between an index of running economy (VO2 per distance) and the temporal electromyographic characteristics of leg muscles were quantified in female runners. Sixteen women performed a 30-min treadmill run at a speed designed to elicit a hard rating of perceived of exertion. Near the end of the run, oxygen uptake, video, and electromyographic data were collected simultaneously. Measures of muscle on-time durations, and on-time coactivation durations were calculated from the following muscles: gastrocnemius, vastus lateralis, rectus femoris, and biceps femoris. Nonparametric correlations between VO2 per distance and temporal electromyographic data were evaluated. Greater on-time duration of rectus femoris during stance, and greater on-time coactivation duration of rectus femoris-gastrocnemius during stance were significantly associated with more economical runners (i.e., lower VO2 per distance). The coactivation of biarticular leg muscles during stance is clearly linked to running economy and this control strategy may elicit greater elastic energy return.

Intraarterial infusion chemotherapy and conformal radiotherapy for cancer of the mouth: prediction of the histological response to therapy with magnetic resonance imaging

BACKGROUND

Although intraarterial chemotherapy has been used to treat head and neck cancers, some cases have shown poor response. If we can predict the response to this therapy on MRI, individual treatment plans may be altered to the most appropriate form of treatment.

PURPOSE

To evaluate whether MRI can predict the histological response to preoperative chemoirradiation in patients with cancer of the mouth.

MATERIAL AND METHODS

This study comprised of 29 consecutive patients with 30 oral cancers. All patients underwent tumor resection after intraarterial infusion chemotherapy and conformal radiotherapy. We compared the margin of the tumor, the presence of bone invasion, tumor area, and volume on pre- and post-treatment MRI with histological responses.

RESULTS

Eighteen lesions showed an excellent response, nine exhibited a good response, and three a poor response. Only the tumor area on pretreatment T1-weighted images and the tumor area and volume on pretreatment enhanced T1-weighted images were significantly correlated with the histological response (P = 0.039, 0.008, and 0.016, respectively); smaller cancers showed better responses. The other factors were not significantly correlated with the histological responses.

CONCLUSION

MRI parameters, excluding initial tumor area and volume, were not predictive of the histological response of oral tumors to preoperative treatment.

Pathological role of osteoclast costimulation in arthritis-induced bone loss

Abnormal T cell immune responses induce aberrant expression of inflammatory cytokines such as TNF-alpha, leading to osteoclastmediated bone erosion and osteoporosis in autoimmune arthritis. However, the mechanism underlying enhanced osteoclastogenesis in arthritis is not completely understood. Here we show that TNF-alpha contributes to inflammatory bone loss by enhancing the osteoclastogenic potential of osteoclast precursor cells through inducing paired Ig-like receptor-A (PIR-A), a costimulatory receptor for receptor activator of NF-kappaB (RANK). In fact, bone erosion and osteoporosis, but not inflammation, caused by aberrant TNF-alpha expression were ameliorated in mice deficient in Fc receptor common gamma subunit or beta(2)-microglobulin, in which the expression of PIR-As and PIR-A ligands is impaired, respectively. These results establish the pathological role of costimulatory receptors for RANK in bone loss in arthritis and may provide a molecular basis for the future therapy of inflammatory diseases.

Novel osteoclast signaling mechanisms

Osteoclasts are cells of monocyte/macrophage origin that degrade bone matrix. Receptor activator of NF-kappaB ligand (RANKL) induces osteoclast differentiation in the presence of macrophage colony-stimulating factor. RANKL activates the tumor necrosis factor receptor-associated factor 6, c-Fos, and calcium signaling pathways, all of which are indispensable for the induction and activation of nuclear factor of activated T cells (NFAT) c1. NFATc1 is the master transcription factor for osteoclast differentiation, which regulates many osteoclast-specific genes. Multiple immunoglobulin-like receptors associated with immunoreceptor tyrosine-based activation motif (ITAM)-harboring adapters, Fc receptor common chi subunit (FcRgamma), and DNAX-activating protein (DAP) 12 mediate costimulatory signals for RANK, which activate calcium signaling through phospholipase Cgamma (PLCgamma). In addition to calcineurin-NFATc1, calcium signaling activates the CaMK-CREB (calcium/calmodulin activated kinase-cyclic AMP-response element binding protein) pathway, which also plays a critical role in osteoclastogenesis. This review summarizes recent advances in the study of signaling mechanisms of osteoclast differentiation.

Increased CD11b expression on polymorphonuclear leucocytes and cytokine profiles in patients with Kawasaki disease

Clinical evidence implicates polymorphonuclear leucocytes in the pathogenesis of vasculitis in Kawasaki disease. We examined modulation of expression of adhesion molecules (CD11b and CD62L) on polymorphonuclear leucocytes and how this expression is related to serum cytokine concentrations. In 18 patients with Kawasaki disease and 15 control subjects, adhesion molecule expression was determined by two-colour immunofluorescence staining of blood leucocytes and flow cytometry. Eight cytokines and chemokines were also measured. In patients with Kawasaki disease, mean fluorescence intensity for CD11b before giving intravenous immunoglobulin was significantly higher than in normal subjects (P<0 x 005). After intravenous immunoglobulin, mean fluorescence intensity for CD11b decreased significantly. With coronary artery lesions present, mean CD11b fluorescence intensity was significantly higher than without coronary artery lesions (P=0 x 005 before intravenous immunoglobulin; P=0 x 024 after intravenous immunoglobulin). No differences were seen in CD62L expression on polymorphonuclear leucocytes between patients with Kawasaki disease and normal subjects. CD11b expression on polymorphonuclear leucocytes correlated positively with serum interleukin (IL)-6, IL-10, granulocyte colony-stimulating factor, percentage of neutrophils among white cells and C-reactive protein. Polymorphonuclear leucocytes from patients with Kawasaki disease showed increased CD11b expression, which was associated with increased serum cytokines and appeared to be related to coronary artery lesions.