Suppression pattern of neutral pions at high transverse momentum in Au + Au collisions at sqrt[sNN]=200 GeV and constraints on medium transport coefficients

For Au + Au collisions at 200 GeV, we measure neutral pion production with good statistics for transverse momentum, pT, up to 20 GeV/c. A fivefold suppression is found, which is essentially constant for 5 < pT < 20 GeV/c. Experimental uncertainties are small enough to constrain any model-dependent parametrization for the transport coefficient of the medium, e.g., q in the parton quenching model. The spectral shape is similar for all collision classes, and the suppression does not saturate in Au + Au collisions.

Magnetic reconnection by a self-retreating X line

Particle-in-cell simulations of collisionless magnetic reconnection are performed to study asymmetric reconnection in which an outflow is blocked by a hard wall while leaving sufficiently large room for the outflow of the opposite direction. This condition leads to a slow, roughly constant motion of the diffusion region away from the wall, the so-called "X-line retreat." The typical retreat speed is approximately 0.1 times the Alfvén speed. At the diffusion region, ion flow pattern shows strong asymmetry and the ion stagnation point and the X line are not collocated. A surprise, however, is that the reconnection rate remains the same unaffected by the retreat motion.

Onset of pi(0) suppression studied in Cu+Cu collisions at sqrt S NN=22.4, 62.4, and 200 GeV

Neutral pion transverse momentum (p(T)) spectra at midrapidity (|y| less than or approximately 0.35) were measured in Cu+Cu collisions at sqrt[s(NN)]=22.4, 62.4, and 200 GeV. Relative to pi_(0) yields in p+p collisions scaled by the number of inelastic nucleon-nucleon collisions (N(coll) the pi_(0) yields for p(T) more than or approximately 2 GeV/c in central Cu+Cu collisions are suppressed at 62.4 and 200 GeV whereas an enhancement is observed at 22.4 GeV. A comparison with a jet-quenching model suggests that final state parton energy loss dominates in central Cu+Cu collisions at 62.4 and 200 GeV, while the enhancement at 22.4 GeV is consistent with nuclear modifications in the initial state alone.

J/psi production in sqrt s_NN=200 GeV Cu+Cu collisions

Yields for J/psi production in Cu+Cu collisions at sqrt s_NN=200 GeV have been measured over the rapidity range |y|<2.2 and compared with results in p+p and Au+Au collisions at the same energy. The Cu+Cu data offer greatly improved precision over existing Au+Au data for J/psi production in collisions with small to intermediate numbers of participants, in the range where the quark-gluon plasma transition threshold is predicted to lie. Cold nuclear matter estimates based on ad hoc fits to d+Au data describe the Cu+Cu data up to N_part approximately 50, corresponding to a Bjorken energy density of at least 1.5 GeV/fm(3).

Expression of vascular endothelial growth factor C is a prognostic indicator in esophageal cancer

BACKGROUND/AIMS

Vascular endothelial growth factor plays an important role in angiogenesis and vascular endothelial growth factor-C is concerned with lymphangiogenesis.

METHODOLOGY

The present study employed immunostaining to investigate the relationship between expression of these factors and clinicopathologic findings in 100 patients with esophageal cancer.

RESULTS

Fifty-six of the 100 tumors (56%) showed expressed vascular endothelial growth factor and 43 tumors (43%) expressed of vascular endothelial growth factor-C. Expression of the latter was correlated with the depth of tumor invasion (p=0.0095), lymphatic invasion (p=0.0065), lymph node metastasis (p=0.0l34). The prognosis was significantly worse for patients with tumors positive for vascular endothelial growth factor-C than for those with negative tumors (p=0.036). In contrast, expression of vascular endothelial growth factor was not correlated with the prognosis. Microvessel density was significantly higher in tumors expressing vascular endothelial growth factor-C compared with negative tumors (p=0.0014). Stepwise multivariate analysis with Cox's proportional hazards model identified gender (p=0.0420), age (p=0.0192), vascular endothelial growth factor-C expression (p=0.0286), and lymphatic invasion (p=0.0030) as prognostic determinants.

CONCLUSIONS

Expression of vascular endothelial growth factor-C is related to lymphatic invasion and is a prognostic indicator for esophageal cancer.

Effects of the time interval between clamping and linear stapling for resection of porcine small intestine

BACKGROUND

Although a wait of several seconds after clamping is recommended when an automatic stapler is used to achieve adequate hemostasis, this wait has not been experimentally clarified.

METHODS

To determine whether waiting is necessary between clamping and firing of a linear stapler, this study evaluated the number of staple line bleeding points and histologic changes in stapling sites of porcine small intestine (n = 46). It also assessed the ratio of dry to wet tissue weight (DW ratio) (n = 20) of porcine small intestine clamped between the prongs of a linear stapler. The sites were studied separately as follows: no wait with a four-row device (n = 12), no wait with a six-row device (n = 11), wait with a four-row device (n = 12), and wait with a six-row device (n = 11). The linear stapler was fired immediately after clamping in the no wait group and 1 min after clamping in the wait group.

RESULTS

The mean number of staple line bleeding points in 2 to 5 min with the six-row device and in 3 to 5 min with the four-row device after firing were significantly less in the wait group than in the no wait group using the same device (p < 0.05). Cross sections of staple lines showed a higher frequency of mucosal cutting in the no wait group than in the wait group for both the four-row and the six-row devices (both significant at p < 0.01). Although the mean wet tissue weights of anastomotic sites did not change in either group, the mean DW ratio was significantly less in the wait group than in the no wait group (p < 0.01).

CONCLUSIONS

A 1-min interval after clamping decreases the amount of clamped tissue. Waiting may thus be necessary to reduce bleeding from stapling sites, which may be related to a decrease in mucosal cutting.

Enhancement of chemosensitivity toward peplomycin by calpastatin-stabilized NF-kappaB p65 in esophageal carcinoma cells: possible involvement of Fas/Fas-L synergism

Chemosensitivity to anticancer drugs was compared between two human esophageal carcinoma cell lines, T.Tn and YES-6 cells. T.Tn cells were more resistant than YES-6 cells to peplomycin (PEP) but not to the other anticancer drugs such as camptothecin, mitomycin C and cytosine arabinoside. Western blot analysis showed higher expression levels of m-calpain and activated mu-calpain in T.Tn cells than in YES-6 cells. On the other hand, YES-6 cells showed a high expression level of calpastatin, which is a calpain-specific endogenous inhibitor. To investigate whether calpain activity was involved in the chemosensitivity, T.Tn cells were transfected with calpastatin cDNA in an inducible expression vector. The induction of calpastatin was accompanied by increased chemosensitivity to PEP. The increases in calpastatin levels were followed by serial increases in the expression levels of NF-kappaB p65 and Fas. Since purified m- or mu-calpain degraded NF-kappaB p65 in vitro, it is possible that calpastatin suppressed calpain-mediated degradation of NF-kappaB p65. Fas ligand (Fas-L) protein levels increased after treatment of the parental T.Tn and calpastatin-transfected cells with PEP, suggesting the synergism between calpastatin-induced Fas and PEP-induced Fas-L. These results suggest that calpain/calpastatin expression levels are effective markers for predicting the sensitivity of human esophageal carcinoma cells to PEP.

Clinical evaluation of QuantiFERON TB-2G test for immunocompromised patients

The usefulness of the tuberculin skin test (TST) and the QuantiFERON TB-2G (QFT-TB) test were compared in immunocompromised patients. The subjects consisted of 252 immunocompromised patients who were clinically suspected of tuberculosis (TB) infection between April 2005 and December 2006. Regarding the underlying diseases, 74 subjects had malignant diseases, 72 were undergoing immunosuppressive treatment, 52 had diabetes mellitus, 50 had chronic renal failure and four had HIV infection. While the positive rate of the QFT-TB test for the diagnosis of TB infection (TB disease or latent TB infection) was 78.1%, that of TST for TB infection was 50.0%. The QFT-TB test was significantly better than TST. However, 32 (13%) patients had an indeterminate QFT-TB result. Indeterminate findings were significantly more frequent in patients receiving immunosuppressive treatment (28%), especially with lymphocytopaenia in the peripheral blood, than in those who had other underlying diseases. While TST-positive and QFT-TB test-negative results were recognised in immunocompromised patients with bacille Calmette-Guérin vaccination or nontuberculous mycobacterial disease, TST-negative and QFT-TB test-positive results were recognised in immunocompromised patients with a past history of TB infection. It was concluded that the QuantiFERON TB-2G test is a more useful diagnostic method for tuberculosis infection than tuberculin skin test for immunocompromised patients suspected of tuberculosis disease. However, because the results of the QuantiFERON TB-2G test show an indeterminate response for patients receiving immunosuppressive treatment, especially for those with lymphocytopaenia due to severe underlying diseases, care must be taken in the interpretation of the QuantiFERON TB-2G test for these patients.

Relation of spasms and myoclonus to suppression-burst on EEG in epileptic encephalopathy in early infancy

PURPOSE

This study was intended to clarify the relation between spasms in series and a suppression-burst (SB) EEG pattern which have a common nature of repetitive bursting activity in epileptic encephalopathy in early infancy.

METHODS

The ictal EEG traces of spasms were temporally compressed and expanded to study the beginning and ending phases of series along with their spectral analysis in two patients with Ohtahara syndrome (OS) and one with early myoclonic encephalopathy (EME). The EEG bursts associated with myoclonus were also investigated.

RESULTS

A mutual transition was indicated between the ictal activity of spasms and the bursts in the peri-series SB on EEG. Gamma rhythm was detected in common in the ictal activity and the peri-series and interictal bursts on EEG, and also in the bursts with myoclonus.

CONCLUSION

The relation between the ictal activity of spasms and SB on EEG was shown to be close. The generative mechanisms of spasms and myoclonus might be linked to the bursting tendency intrinsic to immature brain function.

The signal-induced phospholipid degradation cascade and protein kinase C activation

Acting in synergy with diacylglycerol, unsaturated free fatty acids such as arachidonic, oleic, linoleic, linolenic and docosahexaenoic acids dramatically activate some members of the protein kinase C family at the basal level of Ca2+ concentration. It is plausible that phospholipase C and phospholipase A2, and possibly phospholipase D as well, are involved in the activation of protein kinase C. Presumably, this enzyme activation is integrated into the signal-induced membrane phospholipid degradation cascade, prolonging the activation of protein kinase C. The sustained activity of this enzyme appears to be of importance for long-term cellular responses such as development of neuronal plasticity and gene activation.

A combination chemotherapy of weekly paclitaxel and doxifluridine (5’-DFUR: an intermediate metabolite of capecitabine) in patients with unresectable or recurrent gastric cancer in an outpatient setting. Final results of a multicenter phase II trial

15050

Background: Paclitaxel (PTX) and 5’-DFUR have single-agent activity in gastric cancer and have distinct mechanisms of action and no overlap of key toxicities. Synergistic interaction between PTX and 5’-DFUR is mediated by taxane-induced up-regulation of thymidine phosphorylase, which converts 5’-DFUR to 5-FU. We conducted a combination phase II study of PTX and 5’-DFUR in patients with unresectable or recurrent gastric cancer to evaluate the efficacy and safety in an outpatient. Methods: Eligibility criteria included patients with histologically proven unresectable or recurrent gastric cancer who had measurable lesions fitting RECIST, up to one prior chemotherapy, a performance status of 0–2 and adequate organ function. According to our results of phase I study (Proc ASCO 2004, Abstr. 4228), the treatment included PTX 70 mg/m2 i.v. on days 1, 8, and 15 every 4 weeks and 5’-DFUR 600 mg/body p.o. everyday until there was disease progression or the appearance of unacceptable toxicity. Primary endpoint was: RR; and secondary endpoints were OS, PFS, TTF and onset rate of adverse events. Results: Between June 2004 and July 2006, 42 patients were enrolled in this study: including 34 men; 8 women; median age of 70 years (range, 44–85 years); and PS levels were, zero with 27, one with 13 and two with 2 patients. In 42 eligible patients, clinical usefulness was evaluated resulting in response rate of 40.5% (CR, 1; PR, 16; SD, 17; PD, 6; and NE, 2 patients). The first-line therapy involved 28 patients in whom the response rate was 50.0%. The second-line therapy involved 13 patients (all TS-1 failure) in whom the response rate was 23.1%. OS was 371 days, PFS was 170 days and TTF was 147 days. All patients were treated in outpatient. Severe adverse events were found in 2 patients to discontinue the present treatment, though other adverse events were relatively mild without death due to the present therapy. Commonly observed grade 3/4 adverse events were neutropenia (26.2%), appetite loss (4.8%), neuropathy (4.8%), and fatigue (4.8%). Conclusions: The outpatient combination of a weekly PTX and 5’-DFUR chemotherapy is active and well tolerated.

No significant financial relationships to disclose.

Phase II trial of irinotecan plus cisplatin with concurrent thoracic radiotherapy (TRT) in patients with previously untreated locally advanced non-small cell lung cancer (NSCLC)

18071

Background: The combined modality of the third generation new agent plus cisplatin with concurrent TRT is considered ideal for locally advanced non-small cell lung cancer. However, it is difficult to conduct because of severe toxicities. Methods: Patients fulfilling the following eligibility criteria were enrolled: previously untreated, good performance status (PS 0–2), age <75, stage III, and adequate organ function. The patients received irinotecan 60 mg/m2 i.v. on days 1, 8 and 15, and cisplatin 80 mg/m2 i.v. on day 1 in the first group. The doses were reduced to 50 and 60 mg/m2 in the second group, respectively. Two cycles of chemotherapy were repeated every 4 weeks. Thoracic radiotherapy of 2 Gy/day commenced on day 2 of each chemotherapy cycle, with 28 and 32 Gy administered in the first and second cycles, respectively. Primary endpoint and objective sample size were response rate and 45 patients, respectively. Results: Fifty patients were eligible and 48 (16 in the 1st, 32 in the 2nd group) patients were assessable for response, toxicity and survival. The overall response (OS) was 83% (95% confidence interval (CI), 70–93%). Grade 4 leukopenia, neutropenia, grade 3 or 4 diarrhea, pneumonitis, esophagitis and fatigue occurred in 21%, 48%, 19%, 10% and 19%, respectively. The median time to progression was 8.2 months. The median overall survival time (MST), and the 2- and 5-year survival rates were 20.1 months, 47.1% and 17.1%, respectively. In subgroup analysis, the OS of 1st and 2nd groups were 75% and 88% (not significant), respectively. The MST of 1st and 2nd groups were 13.1 and 33.4 months, respectively, and significant favor with 2nd group (p=0.011). The execution rates of irinotecan on day 15 were significant higher in 2nd (22% vs. 48%) groups (p=0.032), and the survival separated by execution times on day 15 were significantly favor with higher execution time group (p=0.026). Conclusions: This therapy is active and further investigations are warranted at the 2nd group dose level. High execution of chemotherapy on day 15 may be important for the achievement of concurrent chemoradiotherapy.

No significant financial relationships to disclose.

UGT1As polymorphisms predict toxicity in colorectal cancer patients treated with different recommended doses of irinotecan oriented by UGT1A1*28 polymorphism based on previous phase I study

14511

Background: We have presented at 2006 ASCO annual meeting about a genetic UGT1A1 polymorphism oriented phase (P) I study of Irinotecan and 5’-DFUR for metastatic colorectal cancer (MCRC) to determine the maximum tolerated dose (MTD) and the recommend doses (RD) for each UGT1A1 *1/*1 and *1/*28 genotypes. The RD of biweekly Irinotecan administration was 150 mg/m2 for patients (pts) with wild *1/*1 genotype and 70 mg/m2 of Irinotecan for mutated *1/*28. Now we are carrying out a *28 oriented P II study based on this RD. Here we report the profiles of toxicities in the P II study of irinotecan and 5’-DFUR to analyze other kinds of UGT1As polymorphisms in relation to irinotecan toxicities. Patients & Methods: Eligibility criteria were as follows; histologically proven CRC with unresectable metastatic lesions, PS 0–1, age<76, adequate organ functions, and written informed consent. Twenty one pts with wild type genotype and 9 pts with mutated genotype were enrolled. Irinotecan was infused 150 mg/m2 for pts with *1/*1 genotype and 70 mg/m2 for *1/*28. Hematological and non-hematological toxicities were graded, and UGT1As polymorphisms (UGT1A1*6 and *7, UGT1A7*1*2*3*4, UGT1A9*22) were analyzed. Results: Grade (G)3 & 4 toxicities were observed in 6 of 22 (27%) wild type pts and in 3 of 9 (33%) mutated pts, and in 9 of 31 (29%) all pts. There was no significant difference on the profiles of toxicities between the pts with wild genotype and mutated genotype, irrespective of the difference of the quantity of irinotecan. So, the RD was thought to be adequate. In pts with UGT1A1*6 allele, G3 & 4 toxicities were observed 6/11 (55%), on the other hand 3/20 (15%) in pts without *6 allele (p=0.038). G3 & 4 toxicities were also more frequent in pts with UGT1A7*3 alleles than pts without *3 allele (p<0.10). Conclusions: The profiles of toxicities of pts with *1/*1 or *1/*28 genotypes were similar irrespective of the difference of the quantity of irinotecan. The result indicated that the RD of latest PI for each group was adequate, and this P II study is suitable to analyze other kinds of polymorphisms that have correlation to irinotecan toxicities. UGT1A1*6 and UGT1A7*3 allele will be a novel predictor for toxicity of irinotecan.

No significant financial relationships to disclose.

System size and energy dependence of jet-induced hadron pair correlation shapes in Cu+Cu and Au+Au collisions at square root sNN=200 and 62.4 GeV

We present azimuthal angle correlations of intermediate transverse momentum (1-4 GeV/c) hadrons from dijets in Cu+Cu and Au+Au collisions at square root sNN=62.4 and 200 GeV. The away-side dijet induced azimuthal correlation is broadened, non-Gaussian, and peaked away from Delta phi=pi in central and semicentral collisions in all the systems. The broadening and peak location are found to depend upon the number of participants in the collision, but not on the collision energy or beam nuclei. These results are consistent with sound or shock wave models, but pose challenges to Cherenkov gluon radiation models.

J/psi production versus transverse momentum and rapidity in p+p collisions at square root s=200 GeV

J/psi production in p+p collisions at square root s=200 GeV has been measured by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider over a rapidity range of -2.2<y<2.2 and a transverse momentum range of 0<pT<9 GeV/c. The size of the present data set allows a detailed measurement of both the pT and the rapidity distributions and is sufficient to constrain production models. The total cross section times the branching ratio is Bll sigma pp J/psi=178+/-3stat+/-53sys+/-18norm nb.

J/psi production versus centrality, transverse momentum, and rapidity in Au+Au collisions at square root sNN=200 GeV

The PHENIX experiment at the BNL Relativistic Heavy Ion Collider (RHIC) has measured J/psi production for rapidities -2.2<y<2.2 in Au+Au collisions at square root sNN=200 GeV. The J/psi invariant yield and nuclear modification factor RAA as a function of centrality, transverse momentum, and rapidity are reported. A suppression of J/psi relative to binary collision scaling of proton-proton reaction yields is observed. Models which describe the lower energy J/psi data at the CERN Super Proton Synchrotron invoking only J/psi destruction based on the local medium density predict a significantly larger suppression at RHIC and more suppression at midrapidity than at forward rapidity. Both trends are contradicted by our data.

Fine Structural Alterations inTrypanosoma rhodesienseGrown In Vitro, Treated with WR 1635771

Fine-structural alterations in Trypanosoma rhodesiense trypomastigotes exposed to WR 163577, a prophylactic agent against animal African trypanosomiasis, were determined from cells grown in vitro. Exposure of trypomastigotes to a low concentration of drug resulted only in condensation of kinetoplast DNA fibrils. Exposure to higher drug concentrations caused clumping of nuclear chromatin and of cytoplasmic contents. Although alteration of kinetoplast DNA is the first detectable drug-induced change, the function of the kinetoplast in mammalian forms of African trypanosomes is unclear, and the secondary changes in the nucleus and cytoplasm may constitute the functionally significant alterations caused by WR 163577.