Study of B-->D(*)sJ +-D(*) decays

We report a study of D(*)(sJ)(2317)(+) and D(sJ)(2460)(+) meson production in B decays. We observe the decays B+-->D((*)+)(sJ)D ((*)0) and B0-->D((*)+)(sJ)D((*)-) with the subsequent decays D(*)(sJ)(2317)(+)-->D(+)(s)pi(0), D(sJ)(2460)(+)-->D(+)(s)gamma, and D(sJ)(2460)(+)-->D(*+)(s)pi(0). Based on a data sample of 122.1 x 10(6) BB pairs collected with the BABAR detector at the PEP-II B factory, we obtain branching fractions for these modes, including the previously unseen decays B-->D((*)+)(sJ)D(*). In addition, we perform an angular analysis of D(sJ)(2460)(+)-->D(+)(s)gamma decays to test the different D(sJ)(2460)(+) spin hypotheses.

Search for B+/--->[K(-/+)pi(+/-)](D)K+/- and upper limit on the b-->u amplitude in B+/--->DK+/-

We search for B+/--->[K(-/+)pi(+/-)](D)K+/- decays, where [K(-/+)pi(+/-)](D) indicates that the K-/+pi(+/-) pair originates from the decay of a D0 or D (0). Results are based on 120x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector at SLAC. We set an upper limit on the ratio R(Kpi) identical with[Gamma(B+-->[K(-)pi(+)](D)K+)+Gamma(B--->[K(+)pi(-)](D)K-)][Gamma(B+-->[K(+)pi(-)](D) / K+)+Gamma(B--->[K(-)pi(+)](D)K-)]<0.026 (90% C.L.). This constrains the amplitude ratio r(B) identical with|A(B--->D 0K-)/A(B--->D0K-)|<0.22 (90% C.L.), consistent with expectations. The small value of r(B) favored by our analysis suggests that the determination of the Cabibbo-Kobayashi-Maskawa phase gamma from B-->DK will be difficult.

Direct CP violating asymmetry in B0-->K+pi- decays

We present a measurement of the direct CP violating asymmetry in the decay B0-->K+pi(-) using a data sample of 227x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at SLAC. We observe a total signal yield of nK-(pi(+))+nK+(pi(-))=1606+/-51 decays and measure the asymmetry (nK-(pi(+))-nK+(pi(-)))/(nK-(pi(+))+nK+(pi(-)))=-0.133+/-0.030(stat)+/-0.009(syst). The probability of observing such an asymmetry in the absence of direct CP violation is 1.3x10(-5), corresponding to 4.2 standard deviations.

Measurements of CP-violating asymmetries in B0-->K(0)(s)pi(0) decays

We present a measurement of the time-dependent CP-violating (CPV) asymmetries in B0-->K(0)(S)pi(0) decays based on 124x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. In a sample containing 122+/-16 signal decays, we obtain the magnitudes of the direct CPV asymmetry CK(0)(S)(pi(0))=0.40(+0.27)(-0.28)+/-0.09 and of the CPV asymmetry in the interference between mixing and decay SK(0)(S)(pi(0))=0.48(+0.38)(-0.47)+/-0.06 where the first error is statistical and the second systematic.

A Deletion Affecting Several Gene Candidates is Present in the Evergrowing Peach Mutant

Evergrowing (EVG) peach is one of only two described mutants affecting winter dormancy in woody perennial species. EVG peach does not set terminal buds, cease new leaf growth, nor enter into a dormant resting phase in response to winter conditions. The EVG mutation segregates in F2 progeny as a single recessive nuclear gene. A local molecular genetic linkage map around EVG was previously developed using amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers, and a bacterial artificial chromosome (BAC) contig that contains the EVG mutation was assembled. A MADS box coding open reading frame (ORF) was found in a BAC of this contig and used as a probe. The probe detected a polymorphism between the wild-type and mutant genomes, and the polymorphism is indicative of a deletion in EVG peach. The EVG gene region contained six potential MADS-box transcription factor sequences, and the deletion in EVG affected at least four of these. The deletion was bracketed using RFLP analysis, which showed that it is contained within a segment of the genome no greater than 180 kb.

Search for B0 decays to invisible final states and to nunugamma

We establish upper limits on branching fractions for B0 decays to final states where the decay products are purely invisible (i.e., no observable final state particles) and for B0 decays to nunugamma. Within the standard model, these decays have branching fractions that are below current experimental sensitivity, but various models of physics beyond the standard model predict significant contributions from these channels. Using 88.5 x 10(6) BB pairs collected at the Upsilon(4S) resonance by the BABAR experiment at the PEP-II e(+)e- storage ring at the Stanford Linear Accelerator Center, we establish upper limits at the 90% confidence level of 22 x 10(-5) for the branching fraction of B0-->invisible and 4.7 x 10(-5) for the branching fraction of B0-->nunugamma.

Measurement of the B-->Xsl+l- branching fraction with a sum over exclusive modes

We measure the branching fraction for the flavor-changing neutral-current process B-->X(s)l(+)l(-) with a sample of 89x10(6) Upsilon(4S)-->BBmacr; events recorded with the BABAR detector at the PEP-II e(+)e(-) storage ring. The final state is reconstructed from e(+)e(-) or micro(+)micro(-) pairs and a hadronic system X(s) consisting of one K+/- or K(0)(S) and up to two pions, with at most one pi(0). We observe a signal of 40+/-10(stat)+/-2(syst) events and extract the inclusive branching fraction B(B-->X(s)l(+)l(-))=(5.6+/-1.5(stat)+/-0.6(exp syst)+/-1.1(model syst))x10(-6) for ml(+)(l(-))>0.2 GeV/c(2).

Bound on the ratio of decay amplitudes for -B0-->J/psiK*0 and B0-->J/psiK*0

We have measured the time-dependent decay rate for the process B-->J/psiK(*0) (892) in a sample of about 88x10(6) Upsilon(4S)-->B(-)B decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. In this sample we study flavor-tagged events in which one neutral B meson is reconstructed in the J/psiK(*0) or J/psi(-)K(*0) final state. We measure the coefficients of the cosine and sine terms in the time-dependent asymmetries for J/psiK(*0) and J/psi(-)K(*0), find them to be consistent with the standard model expectations, and set upper limits at 90% confidence level (C.L.) on the decay amplitude ratios |A((-)B(0)-->J/psiK(*0))|/|A(B0-->J/psiK(*0))|<0.26 and |A(B0-->J/psi(-)K(*0))|/|A((-)B(0)-->J/psi(-)K(*0))|<0.32. For a single ratio of wrong-flavor to favored amplitudes for B0 and (-)B(0) combined, we obtain an upper limit of 0.25 at 90% C.L.

Measurement of the time-dependent CP asymmetry in the B0-->phiK0 decay

We present a measurement of the time-dependent CP asymmetry for the neutral B-meson decay B0-->phiK0. We use a sample of approximately 114 x 10(6) B-meson pairs taken at the Upsilon(4S) resonance with the BABAR detector at the PEP-II B-meson factory at SLAC. We reconstruct the CP eigenstates phiK0S and phiK0L, where phi-->K+K-, K0S-->pi+pi-, and K0L is observed via its hadronic interactions. The other B meson in the event is tagged as either a B0 or Bbar0 from its decay products. The values of the CP-violation parameters are SphiK=0.47+/-0.34(stat)+0.08-0.06(syst) and CphiK=0.01+/-0.33(stat)+/-0.10(syst).

Measurement of the direct CP asymmetry in b-->s gamma Decays

We describe a measurement of the direct CP asymmetry between inclusive b-->s gamma and b-->s gamma decays. This asymmetry is expected to be less than 0.01 in the standard model, but could be enhanced up to about 0.10 by new physics contributions. We use a sample of 89 x 10(6) BB pairs recorded with the BABAR detector at SLAC PEP-II, from which we reconstruct a set of 12 exclusive b-->s gamma final states containing one charged or neutral kaon and one to three pions. We measure an asymmetry of A(CP)(b-->s gamma)=0.025+/-0.050(stat)+/-0.015(syst), corresponding to an allowed range of -0.06<A(CP)(b-->s gamma)<+0.11 at 90% confidence level.

[Postoperative prognostic analysis of 96 patients with stage I non-small cell lung cancer]

BACKGROUND

To compare the postoperative survival difference between stage IA and IB non-small cell lung cancer ( NSCLC) and analyze the prognostic factors affecting the long-term survival of resected stage I NSCLC.

METHODS

Ninety-six patients with stage I NSCLC surgically treated in our department from 1974 to 1995 were studied retrospectively. Nine possible prognostic factors including gender, age, T grade, primary tumor size, visceral pleural involvement , type of resection, pathological type, tumor differentiation, and location were analyzed by univariate analysis and multivariate analysis subsequently.

RESULTS

There was a significant difference in postoperative 5-year survival between stage IA and IB ( P < 0. 05) . The significant prognostic factors ( P < 0. 05) demonstrated by univariate analysis included T grade, primary tumor size, visceral pleural involvement and tumor differentiation, while visceral pleural involvement and tumor differentiation served as the independent prognostic factors ( P < 0. 05) with multivariate analysis.

CONCLUSIONS

Stage I NSCLC should be subdivided into IA and IB whose five-year survival was proved to be significantly different. Visceral pleural involvement as well as tumor differentiation played as the independent prognostic factors in resected stage I NSCLC.

Hepatocyte growth factor/scatter factor blocks the mitochondrial pathway of apoptosis signaling in breast cancer cells

The cytokine hepatocyte growth factor/scatter factor (HGF/SF) has been found to protect a variety of epithelial and cancer cell types against cytotoxicity and apoptosis induced by DNA damage, but the specific apoptotic signaling events and the levels at which they are blocked by HGF/SF have not been identified. We found that treatment of MDA-MB-453 human breast cancer cells with adriamycin (also known as doxorubicin, a DNA topoisomerase IIalpha inhibitor) induced a series of time-dependent events, including the mitochondrial release of cytochrome c and apoptosis-inducing factor, mitochondrial membrane depolarization, activation of a set of caspases (caspase-9, -3, -7, -2, and -8), cleavage of poly(ADP-ribose) polymerase (PARP), and up-regulation of expression of the Fas ligand. All of these events were blocked by preincubation of the cells with HGF/SF. In contrast, the pan-caspase inhibitor benzyloxycarbonyl-VAD-fluoromethylketone blocked some of these events (e.g. caspase-3 activation and PARP cleavage) but did not block cytochrome c release or mitochondrial depolarization. These findings suggest that HGF/SF functions, in part, upstream of the mitochondria to block mitochondrial apoptosis signaling, prevent activation of multiple caspases, and protect breast cancer cells against apoptosis.

Mutant BRCA1 genes antagonize phenotype of wild-type BRCA1

Unregulated expression of wild-type BRCA1 (wtBRCA1) confers an altered phenotype in cultured human prostate cancer cells, characterized by chemosensitivity, susceptibility to apoptosis, decreased DNA repair activity, and alterations of key cell regulatory proteins. We now report that the expression of truncated or mutant full-length BRCA1 genes can abrogate certain phenotypic characteristics and/or confer the opposite phenotype to the wild-type BRCA1 gene. In particular, several carboxyl-terminal truncated BRCA1 proteins conferred chemoresistance, decreased susceptibility to apoptosis, and decreased ability to suppress in vivo tumor growth. These truncated BRCA1 proteins also blocked the ability of ectopically expressed wtBRCA1 to induce chemosensitivity and to inhibit estrogen receptor transcriptional activity. Studies using epitope-tagged truncated proteins confirmed their expression, nuclear localization, and functionality. On the other hand, in cells with no endogenous wild-type BRCA1 (HCC1937 human breast cancer cells), the wtBRCA1 gene enhanced cellular DNA repair activity and rendered the cells resistant to DNA damage; while truncated BRCA1 proteins blocked the wtBRCA1-induced chemoresistance. Our findings suggest that truncated BRCA1 proteins can inhibit the function of wild-type BRCA1. They raise the possibility that some inherited BRCA1 mutations may actively promote oncogenesis by blocking the function of the remaining wild-type BRCA1 allele, although this hypothesis remains to be proved.

Altered gene expression pattern in cultured human breast cancer cells treated with hepatocyte growth factor/scatter factor in the setting of DNA damage

The cytokine hepatocyte growth factor/scatter factor (HGF/SF) protects epithelial and cancer cells against DNA-damaging agents via a pathway involving signaling from c-Met --> phosphatidylinositol-3- kinase --> c-Akt. However, the downstream alterations in gene expression resulting from this pathway have not been established. On the basis of cDNA microarray and semiquantitative RT-PCR assays, we found that MDA-MB-453 human breast cancer cells preincubated with HGF/SF and then exposed to Adriamycin (ADR), a DNA topoisomerase II inhibitor, exhibit an altered pattern of gene expression, as compared with cells treated with ADR only. [HGF/SF+ADR]-treated cells showed altered expression of genes involved in the DNA damage response, cell cycle regulation, signal transduction, metabolism, and development. Some of these alterations suggest mechanisms by which HGF/SF may exert its protective activity, e.g., up-regulation of polycystic kidney disease-1 (a survival-promoting component of cadherin-catenin complexes), down-regulation of 51C (an inositol polyphosphate-5-phosphatase), and down-regulation of TOPBP1 (a topoisomerase IIB binding protein). We showed that enforced expression of the cdc42-interacting protein CIP4, a cytoskeleton-associated protein for which expression was decreased in [HGF/SF+ADR]-treated cells, inhibited HGF/SF-mediated protection against ADR. The cDNA microarray approach may open up new avenues for investigation of the DNA damage response and its regulation by HGF/SF.

Additive activation of hepatic NF-kappaB by ethanol and hepatitis B protein X (HBX) or HCV core protein: involvement of TNF-alpha receptor 1-independent and -dependent mechanisms

Alcohol consumption and viral hepatitis infection synergistically accelerate liver injury, but the underlying mechanism is not fully understood. Here we have examined the effects of ethanol on hepatitis B protein X (HBX)- or hepatitis C core protein (HCV core protein)-mediated activation of NF-kappaB, a critical signal in hepatic injury, regeneration, and tumor transformation. Acute ethanol or acetaldehyde exposure potentiates HBX or HCV core protein activation of NF-kappaB in primary mouse hepatocytes. Such potentiation can be abolished by blocking ethanol metabolism or overexpression of dominant negative NF-kappaB-inducing kinase (NIK), IkappaB kinase (IKK), or IkappaB. Moreover, pertussis toxin attenuates NF-kappaB activation induced by acetaldehyde but not by HBX or HCV core protein, whereas HBX or HCV core protein-mediated activation of NF-kappaB is abolished completely in tumor necrosis factor a receptor 1 (TNFR1) (-/-) hepatocytes. Finally, chronic ethanol consumption induces hepatic CYP2E1 protein expression and potentiates HBX or HCV core protein activation of NF-kappaB in the liver. These findings suggest that ethanol activates hepatic NF-kappaB via its metabolism and that HBX or HCV core protein activates hepatic NF-kappaB via TNFR1. With the essential role of TNFR1 in alcoholic liver injury, targeting TNFR1 by hepatitis viral proteins could contribute to cooperative effects of alcohol consumption and viral hepatitis on liver disease.

[Comparison of acute cellular rejection between living donor liver transplantation and cadaveric liver transplantation]

OBJECTIVE

To compare the incidence and severity of acute cwellular rejection (ACR) between living donor liver transplantation (LDLT) and cadaveric liver transplantation (CLT).

METHODS

51 patients underwent LDLT among which 30 received the liver of blood-related donors, and 65 patients underwent CLT. Clinical data, such as the cold ischemic time of liver graft, use of immunosuppressive agents, ACR rate, response to steroid therapy, HLA matching between donor and recipient, and survival rates of liver graft and patients were collected and analyzed.

RESULTS

The graft survival rate, patient survival rate, ACR rate, ACR multiple incidence rate, and no response rate to steroid therapy in CLT and LDLT groups were 72% vs 78%, 77% vs. 78%, 48% vs. 41%, 20% vs. 10%, and 11% vs. 4% (P > 0.05). The difference of ACR rates between CLT and living blood-related donor liver transplantation was statistically insignificant. There was no significant difference in number of HLA allele mismatching between patients with ACR and those without ACR. The combined immunosuppression therapy rely mainly on FK506 use reduced the occurrence of ACR (P < 0.05).

CONCLUSION

There is no marked difference in incidence of ACR between LDLT and CLT. ACR in liver transplantation is correlated to neither HLA matching between donors and recipients nor to cold ischemic time of the liver graft. FK506 avoids ACR better than cyclosporin2 A.

Effect of postmenopausal hormone replacement therapy on lipoprotein and homocysteine levels in Chinese women

Epidemiological studies have revealed that postmenopausal estrogen replacement therapy results in a marked reduction in the risk for cardiovascular diseases. In the present study, we evaluated plasma lipoprotein profile as well as homocysteine levels in 145 postmenopausal and premenopausal Chinese women living in Hong Kong. We also investigated the effect of hormone-replacement therapy (HRT) with estrogen or estrogen combined with progestin on plasma lipoprotein profile and homocysteine concentrations in those individuals. Postmenopausal women displayed significantly higher plasma levels of total cholesterol, LDL-cholesterol and apoB as well as higher plasma homocysteine levels than that of premenopausal women. HRT with either estrogen (17beta-estradiol or conjugated equine estrogen) alone or estrogen combined with progestin for 3.5-4.5 years significantly improved the lipoprotein profile in postmenopausal women by decreasing the levels of total cholesterol (12-20% reduction), LDL-cholesterol (26-29% reduction) and apoB (21-25% reduction). In women treated with 17beta-estradiol or conjugated equine estrogens their plasma levels of apoAl were significantly elevated (18% elevation) as compared to non-users. HRT also reduced plasma concentrations of homocysteine (13-15% reduction). In conclusion, we found that long-term HRT was associated with improvement in plasma lipoprotein profile and a reduction in homocysteine concentration in postmenopausal women. These results support the notion that the improvement of lipoprotein profile and a reduction in homocysteine concentration may contribute to the beneficial effect of HRT on cardiovascular risk.

Disruption of BRCA1 LXCXE motif alters BRCA1 functional activity and regulation of RB family but not RB protein binding

The tumor suppressor activity of the BRCA1 gene product is due, in part, to functional interactions with other tumor suppressors, including p53 and the retinoblastoma (RB) protein. RB binding sites on BRCA1 were identified in the C-terminal BRCT domain (Yarden and Brody, 1999) and in the N-terminus (aa 304-394) (Aprelikova et al., 1999). The N-terminal site contains a consensus RB binding motif, LXCXE (aa 358-362), but the role of this motif in RB binding and BRCA1 functional activity is unclear. In both in vitro and in vivo assays, we found that the BRCA1:RB interaction does not require the BRCA1 LXCXE motif, nor does it require an intact A/B binding pocket of RB. In addition, nuclear co-localization of the endogenous BRCA1 and RB proteins was observed. Over-expression of wild-type BRCA1 (wtBRCA1) did not cause cell cycle arrest but did cause down-regulation of expression of RB, p107, p130, and other proteins (e.g., p300), associated with increased sensitivity to DNA-damaging agents. In contrast, expression of a full-length BRCA1 with an LXCXE inactivating mutation (LXCXE-->RXRXH) failed to down-regulate RB, blocked the down-regulation of RB by wtBRCA1, induced chemoresistance, and abrogated the ability of BRCA1 to mediate tumor growth suppression of DU-145 prostate cancer cells. wtBRCA1-induced chemosensitivity was partially reversed by expression of either Rb or p300 and fully reversed by co-expression of Rb plus p300. Our findings suggest that: (1) disruption of the LXCXE motif within the N-terminal RB binding region alters the biologic function of BRCA1; and (2) over-expression of BRCA1 inhibits the expression of RB and RB family (p107 and p130) proteins.

The multisubstrate adapter Gab1 regulates hepatocyte growth factor (scatter factor)-c-Met signaling for cell survival and DNA repair

Hepatocyte growth factor (scatter factor) (HGF/SF) is a pleiotrophic mediator of epithelial cell motility, morphogenesis, angiogenesis, and tumorigenesis. HGF/SF protects cells against DNA damage by a pathway from its receptor c-Met to phosphatidylinositol 3-kinase (PI3K) to c-Akt, resulting in enhanced DNA repair and decreased apoptosis. We now show that protection against the DNA-damaging agent adriamycin (ADR; topoisomerase IIalpha inhibitor) requires the Grb2-binding site of c-Met, and overexpression of the Grb2-associated binder Gab1 (a multisubstrate adapter required for epithelial morphogenesis) inhibits the ability of HGF/SF to protect MDCK epithelial cells against ADR. In contrast to Gab1 and its homolog Gab2, overexpression of c-Cb1, another multisubstrate adapter that associates with c-Met, did not affect protection. Gab1 blocked the ability of HGF/SF to cause the sustained activation of c-Akt and c-Akt signaling (FKHR phosphorylation). The Gab1 inhibition of sustained c-Akt activation and of cell protection did not require the Gab1 pleckstrin homology or SHP2 phosphatase-binding domain but did require the PI3K-binding domain. HGF/SF protection of parental MDCK cells was blocked by wortmannin, expression of PTEN, and dominant negative mutants of p85 (regulatory subunit of PI3K), Akt, and Pak1; the protection of cells overexpressing Gab1 was restored by wild-type or activated mutants of p85, Akt, and Pak1. These findings suggest that the adapter Gab1 may redirect c-Met signaling through PI3K away from a c-Akt/Pak1 cell survival pathway.

A study of equivalent source techniques for high-resolution EEG imaging

High-resolution EEG imaging has been an important topic in recent EEG research, and much work has been done on the two equivalent source imaging techniques: the equivalent distributed dipole-layer source imaging technique (EST) and the equivalent multipole source imaging technique (SAT). In this paper we first develop a forward density formula for a spherical equivalent distributed dipole layer of an arbitrary dipole in a three-concentric-sphere head model. It is clarified using the derived forward formula that the equivalent dipole-layer source and equivalent multipole source are interrelated in theory. Finally, simulation comparisons are conducted, the results of which suggest that EST has a higher spatial resolution than SAT when both of them are implemented by a truncated singular value decomposition algorithm. This is due to the different singularities of the inversion equations involved in the two techniques. An empirical VEP data study also shows that EST is better than SAT in providing higher spatial resolution EEG imaging.