bluuebunny/crossref_metadata_2025 huggingface dataset:
Age-Related Reduction in Estrogen Receptor–Mediated Mechanisms of Vascular Relaxation in Female Spontaneously Hypertensive Rats
Authors: Wynne Fanisha L. , Payne Jason A. , Cain Ashley E. , Reckelhoff Jane F. , Khalil Raouf A.
Published: December 2003

Hypertension increases with aging, and changes in vascular estrogen receptors (ERs) may play a role in age-related hypertension in women. We tested whether age-related increases in blood pressure in female spontaneously hypertensive rats (SHRs) are associated with reduction in amount and/or vascular relaxation effects of estrogen and ER. Arterial pressure and plasma estradiol were measured in adult (12 weeks) and aging (16 months) female SHRs, and thoracic aorta was isolated for measurement of active stress,
45
Ca
2+
influx, and ERs. Arterial pressure was greater and plasma estradiol was less in aging females than in adult females. In aorta of adult females, Western blots revealed α- and β-ERs that were slightly reduced in aging rats. In endothelium-intact vascular strips, phenylephrine (Phe; 10
−5
mol/L) caused greater active stress in aging rats (9.3±0.2) than in adult rats (6.2±0.3×10
4
N/m
2
). 17β-estradiol (E2) caused relaxation of Phe contraction and stimulation of vascular nitrite/nitrate production, which was reduced in aging rats. In endothelium-denuded strips, E2 still caused relaxation of Phe contraction, which was smaller in aging rats than adult rats. KCl (51 mmol/L), which stimulates Ca
2+
influx, produced greater active stress in aging rats (9.1±0.3) than in adult rats (5.9±0.2×10
4
N/m
2
). E2 caused relaxation of KCl contraction and inhibition of Phe- and KCl-induced
45
Ca
2+
influx, which were reduced in aging rats. Thus, aging in female SHR is associated with reduction in ER-mediated NO production from endothelial cells and decrease in inhibitory effects of estrogen on Ca
2+
entry mechanisms of smooth muscle contraction. The age-related decrease in ER-mediated vascular relaxation may explain the increased vascular contraction and arterial pressure associated with aging in females.
Isoprenylcysteine Carboxyl Methyltransferase Modulates Endothelial Monolayer Permeability
Authors: Lu Qing , Harrington Elizabeth O. , Hai Chi-Ming , Newton Julie , Garber Megan , Hirase Tetsuaki , Rounds Sharon
Published: December 2003

RhoA and Rac1 regulate formation of stress fibers and intercellular junctions, thus modulating endothelial monolayer permeability. Posttranslational modifications of RhoA and Rac1 regulate enzyme activity and subcellular localization, resulting in altered cellular function. The role of RhoA and Rac1 carboxyl methylation in modulating endothelial monolayer permeability is not known. In this study, we found that inhibition of isoprenylcysteine-
O
-carboxyl methyltransferase (ICMT) with adenosine plus homocysteine or
N
-acetyl-
S
-geranylgeranyl-
l
-cysteine decreased RhoA carboxyl methylation, RhoA activity, and endothelial monolayer permeability, suggesting that RhoA carboxyl methylation may play a role in the ICMT-modulated monolayer permeability. Similar studies showed no effect of ICMT inhibition on Rac1 carboxyl methylation or localization. Bovine pulmonary artery endothelial cells (PAECs) stably overexpressing ICMT-GFP cDNA were established to determine if increased ICMT expression could alter RhoA or Rac1 carboxyl methylation, activation, and endothelial monolayer permeability. PAECs stably overexpressing ICMT demonstrated increased RhoA carboxyl methylation, membrane-bound RhoA, and RhoA activity. Additionally, PAECs stably overexpressing ICMT had diminished VE-cadherin and β-catenin at intercellular junctions, with resultant intercellular gap formation, as well as enhanced monolayer permeability. These effects were blunted by adenosine plus homocysteine and by inhibition of RhoA, but not by inhibition of Rac1. These results indicate that ICMT modulates endothelial monolayer permeability by altering RhoA carboxyl methylation and activation, thus changing the organization of intercellular junctions. Therefore, carboxyl methylation of RhoA may modulate endothelial barrier function.
Regulation of Connexin43 Protein Complexes by Intracellular Acidification
Authors: Duffy Heather S. , Ashton Anthony W. , O’Donnell Phyllis , Coombs Wanda , Taffet Steve M. , Delmar Mario , Spray David C.
Published: December 2003

Ischemia-induced acidification of astrocytes or cardiac myocytes reduces intercellular communication by closing gap junction channels and subsequently internalizing gap junction proteins. To determine whether such coupling changes might be attributable to altered interactions between connexin43 (Cx43) and other proteins, we applied the nigericin/high K
+
method to vary intracellular pH (pHi) in cultured cortical astrocytes. Intracellular acidification was accompanied by internalization of Cx43 with retention of Cx43 scaffolding protein Zonula Occludens-1 (ZO-1) at cell surfaces, suggesting that ZO-1 and Cx43 dissociate at low pHi. Coimmunoprecipitation studies revealed decreased binding of ZO-1 and increased binding of c-Src to Cx43 at low pHi. Resonant mirror spectroscopy was used to quantify binding of the SH3 domain of c-Src and the PDZ domains of ZO-1 to the carboxyl terminal domain of Cx43 (Cx43CT). Data indicate that the c-Src/Cx43CT interaction is highly pH dependent whereas the ZO-1/Cx43CT interaction is not. Moreover, binding of c-Src to Cx43CT prevented and reversed ZO-1/Cx43CT binding. We hypothesize that increased affinity of c-Src for Cx43 at low pHi aids in separation of Cx43 from ZO-1 and that this may facilitate internalization of Cx43. These data suggest that protracted acidification may remodel protein-protein interactions involving Cx43 and thus provide an important protective mechanism to limit lesion spread after ischemic injury.
Overexpression of CXCR4 on human CD34+ progenitors increases their proliferation, migration, and NOD/SCID repopulation
Authors: Kahn Joy , Byk Tamara , Jansson-Sjostrand Lottie , Petit Isabelle , Shivtiel Shoham , Nagler Arnon , Hardan Izhar , Deutsch Varda , Gazit Zulma , Gazit Dan , Karlsson Stefan , Lapidot Tsvee
Published: December 2003

A major limitation to clinical stem cell–mediated gene therapy protocols is the low levels of engraftment by transduced progenitors. We report that CXCR4 overexpression on human CD34+ progenitors using a lentiviral gene transfer technique helped navigate these cells to the murine bone marrow and spleen in response to stromal-derived factor 1 (SDF-1) signaling. Cells overexpressing CXCR4 exhibited significant increases in SDF-1–mediated chemotaxis and actin polymerization compared with control cells. A major advantage of CXCR4 overexpression was demonstrated by the ability of transduced CD34+ cells to respond to lower, physiologic levels of SDF-1 when compared to control cells, leading to improved SDF-1–induced migration and proliferation/survival, and finally resulting in significantly higher levels of in vivo repopulation of nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice including primitive CD34+/CD38-/low cells. Importantly, no cellular transformation was observed following transduction with the CXCR4 vector. Unexpectedly, we documented lack of receptor internalization in response to high levels of SDF-1, which can also contribute to increased migration and proliferation by the transduced CD34+ cells. Our results suggest CXCR4 overexpression for improved definitive human stem cell motility, retention, and multilineage repopulation, which could be beneficial for in vivo navigation and expansion of hematopoietic progenitors. (Blood. 2004;103:2942-2949)
Cognate recognition of the endothelium induces HY-specific CD8+ T-lymphocyte transendothelial migration (diapedesis) in vivo
Authors: Marelli-Berg Federica M. , James Martha J. , Dangerfield John , Dyson Julian , Millrain Maggie , Scott Diane , Simpson Elizabeth , Nourshargh Sussan , Lechler Robert I.
Published: December 2003

The physiologic significance of MHC-peptide complex presentation by endothelial cells (ECs) to trafficking T lymphocytes remains unresolved. On the basis of our observation that cognate recognition of ECs enhanced transendothelial migration of antigen-specific T lymphocytes in vitro, we have proposed that by displaying antigenic peptides from the underlying tissue, ECs promote the recruitment of antigen-specific T cells. In this study, we have tested this hypothesis by comparing the trafficking of HY-specific T lymphocytes into antigenic and nonantigenic tissue using in vivo models of T-cell recruitment. Up-regulated expression of H2 molecules presenting endogenous antigen in the peritoneal mesothelium and vessels led to the local recruitment of HY-specific T cells in male, but not female, mice. Intravital microscopy experiments analyzing EC–HY-specific T-cell interactions in the cremasteric vascular bed revealed that cognate recognition of the endothelium results in enhanced diapedesis of T cells into the tissue, while not affecting rolling and adhesion. Our results are consistent with the hypothesis that, under inflammatory conditions, antigen presentation by the endothelium contributes to the development and specificity of T-cell–mediated inflammation by favoring the selective migration of antigen-specific T cells. (Blood. 2004;103:3111-3116)
A cell-surface molecule selectively expressed on murine natural interferon–producing cells that blocks secretion of interferon-alpha
Authors: Blasius Amanda , Vermi William , Krug Anne , Facchetti Fabio , Cella Marina , Colonna Marco
Published: December 2003

Natural interferon (IFN)-producing cells (IPCs) recognize certain viruses and DNA containing deoxycytidylate-phosphatedeoxyguanylate (CpG) motifs through the toll-like receptor (TLR) 9, resulting in secretion of IFN-α, interleukin 12 (IL-12), and proinflammatory chemokines. Human IPCs are found mainly in inflamed lymph nodes, where they are presumably recruited from the blood to activate both innate and adaptive responses to microbial infections. Demonstrating IPC recruitment and function in murine infection models has been difficult because multiple antibodies are required to distinguish IPCs from other immune cells and very few IPCs can be recovered from lymph nodes. Here we describe a monoclonal antibody (mAb) that exclusively detects murine IPCs in all lymphoid organs under both normal and inflammatory conditions. Using this antibody, we demonstrate that IPCs are normally present in the T-cell zone of lymph nodes and spleen and that inoculation of peripheral tissues with inflammatory stimuli triggers recruitment of IPC into sentinel lymph nodes, whether the stimuli are able to directly stimulate IPCs through TLR or not. Remarkably, we show that incubation of IPCs with the antibody in vitro or administration of the antibody in vivo dramatically reduce secretion of IFN-α in response to CpG DNA without causing IPC depletion. Thus, the antibody identifies an IPC-specific surface molecule that, when engaged, inhibits IFN-α secretion. (Blood. 2004;103:4201-4206)
Do thymically and strictly extrathymically developing T cells generate similar immune responses?
Authors: Blais Marie-Ève , Gérard Gwladys , Martinic Marianne M. , Roy-Proulx Guillaume , Zinkernagel Rolf M. , Perreault Claude
Published: December 2003

If present in sufficient numbers, could extrathymic T cells substitute for thymus-derived T cells? To address this issue, we studied extrathymic T cells that develop in athymic mice under the influence of oncostatin M (OM). In this model, extensive T-cell development is probably due to amplification of a minor pathway of T-cell differentiation taking place only in the lymph nodes. Extrathymic CD4 T cells expanded poorly and were deficient in providing B-cell help after infection with vesicular stomatitis virus (VSV) and lymphocytic choriomeningitis virus (LCMV). Compared with classic T cells, stimulated extrathymic CD8 T cells produced copious amounts of interferon γ (IFN-γ), and their expansion was precocious but of limited amplitude because of a high apoptosis rate. Consequently, although extrathymic cytotoxic T lymphocytes (CTLs) responded to LCMV infection, as evidenced by the expansion of GP33-41 tetramer-positive CD8 T cells, they were unable to eradicate the virus. Our data indicate that the site of development impinges on T-cell quality and function and that extrathymic T cells functionally cannot substitute for classical thymic T cells. (Blood. 2004;103:3102-3110)
The pattern and distribution of immunoglobulin VH gene mutations in chronic lymphocytic leukemia B cells are consistent with the canonical somatic hypermutation process
Authors: Messmer Bradley T. , Albesiano Emilia , Messmer Davorka , Chiorazzi Nicholas
Published: December 2003

The overexpanded clone in most B-cell-type chronic lymphocytic leukemia (BCLL) patients expresses an immunoglobulin (Ig) heavy chain variable (VH) region gene with some level of mutation. While it is presumed that these mutations were introduced in the progenitor cell of the leukemic clone by the canonical somatic hypermutation (SHM) process, direct evidence of such is lacking. Nucleotide sequences of the Ig VH genes from 172 B-CLL patients were analyzed. Previously described VH gene usage biases were noted. As with canonical SHM, mutations found in B-CLL were more frequent in RGYW hot spots (mutations in an RGYW motif = 44.1%; germ line frequency of RGYW motifs = 25.6%) and favored transitions over transversions (transition-transversion ratio = 1.29). Significantly, transition preference was also noted when only mutations in the wobble position of degenerate codons were considered. Wobble positions are inherently unselected since regardless of change an identical amino acid is encoded; therefore, they represent a window into the nucleotide bias of the mutational mechanism. B-CLL VH mutations concentrated in complementarity-determining region 1 (CDR1) and CDR2, which exhibited higher replacement-to-silent ratios (CDR R/S, 4.60; framework region [FR] R/S, 1.72). These results are consistent with the notion that VH mutations in B-CLL cells result from canonical SHM and select for altered, structurally sound antigen receptors. (Blood. 2004;103:3490-3495)
Erythropoietin gene therapy leads to autoimmune anemia in macaques
Authors: Gao Guangping , Lebherz Corinna , Weiner Daniel J. , Grant Rebecca , Calcedo Roberto , McCullough Beth , Bagg Adam , Zhang Yi , Wilson James M.
Published: December 2003

Gene therapy is being considered for the delivery of therapeutic proteins. We evaluated the delivery of the hormone erythropoietin (EPO) into cynomolgus macaques through intramuscularly administered adeno-associated virus (AAV) vectors. As expected, the animals developed supraphysiologic levels of EPO and polycythemia. However, severe anemia ensued in some animals because of an autoimmune response to endogenous and transgene derived EPO. This is the first example of gene therapy leading to inadvertent auto-immunity in primates. (Blood. 2004;103: 3300-3302)
4-1BB-dependent inhibition of immunosuppression by activated CD4+CD25+ T cells
Authors: Choi Beom K , Bae Jun S , Choi Eun M , Kang Woo J , Sakaguchi Shimon , Vinay Dass S , Kwon Byoung S
Published: December 2003

4-1BB (CD137) is a costimulatory molecule involved in the activation and survival of CD4, CD8, and natural killer cells. Although a great deal has been learned as to how 4-1BB-mediated signaling governs the immunity of conventional T cells, the functional role of 4-1BB in the context of CD4+CD25+ regulatory T cell (Tr) activation is largely unknown. Using 4-1BB-intact and -deficient mice, we investigated the effect of the 4-1BB/4-1BB ligand pathway on the suppressive function of Tr cells. Our data indicate that although 4-1BB is expressed on Tr cells, its contribution to their proliferation is minimal. We also showed that signaling through the 4-1BB receptor inhibited the suppressive function of Tr cells in vitro and in vivo. It is interesting that anti-4-1BB-mediated but not anti-GITR-directed inhibition was more potent when Tr cells were preactivated. Collectively, these data indicate that 4-1BB signaling is critical in Tr cell immunity.
Biweekly 72-Hour 9-Aminocamptothecin Infusion As Second-Line Therapy for Ovarian Carcinoma: Phase II Study of the New York Gynecologic Oncology Group and the Eastern Cooperative Oncology Group
Authors: Hochster Howard , Plimack Elizabeth R. , Runowicz Carolyn D. , Speyer James , Wallach Robert C. , Sorich Joan , Mandeli John , Wadler Scott , Wright John , Muggia Franco M.
Published: December 2003

Purpose

To determine the antitumor activity of the novel topoisomerase I inhibitor 9-aminocamptothecin (9-AC) given over 72 hours every 2 weeks in patients with ovarian carcinoma previously treated with one platinum-containing regimen.

Patients and Methods

Patients with ovarian carcinoma who received one prior platinum-containing regimen were eligible. Patients were stratified based on whether their disease was measurable, or nonmeasurable but assessable. 9-AC 35 μg/m2/h was administered by continuous infusion for 72 hours every 2 weeks via ambulatory pump.

Results

Sixty patients were entered, 32 with measurable and 28 with nonmeasurable but assessable disease. Ten (16.7%) of 60 patients responded (95% CI, 7.2% to 26.1%), with four complete responses and six partial remissions. The response rate for patients with measurable and nonmeasurable but assessable disease was 22% (95% CI, 7.6% to 36.2%) and 10.7% (95% CI, 2.3% to 28.2%), respectively. None of the responders were platinum-resistant. Nineteen patients (32%) had stable disease. The major toxicities were hematologic, with 25% of patients having grade 3 and 35% having grade 4 neutropenia, including five episodes of febrile neutropenia, 17% having grade 3 to 4 thrombocytopenia, and 27% having grade 3 to 4 anemia. Nonhematologic toxicity included grade 3 to 4 nausea (27%) and grade 3 to 4 vomiting (12%).

Conclusion

This phase II multicenter trial of biweekly 72 hour 9-AC infusion as second-line therapy for ovarian cancer demonstrates comparable activity to standard approved agents in patients with both measurable and nonmeasurable but assessable disease. Toxicity consists mainly of moderate but controllable myelosuppression. Further studies combining 9-AC with other agents active in ovarian cancer for use as second-line therapy are warranted.
Methadone Versus Morphine As a First-Line Strong Opioid for Cancer Pain: A Randomized, Double-Blind Study
Authors: Bruera Eduardo , Palmer J. Lynn , Bosnjak Snezana , Rico Maria Antonieta , Moyano Jairo , Sweeney Catherine , Strasser Florian , Willey Jie , Bertolino Mariela , Mathias Clarissa , Spruyt Odette , Fisch Michael J.
Published: December 2003

Purpose

To compare the effectiveness and side effects of methadone and morphine as first-line treatment with opioids for cancer pain.

Patients and Methods

Patients in international palliative care clinics with pain requiring initiation of strong opioids were randomly assigned to receive methadone (7.5 mg orally every 12 hours and 5 mg every 4 hours as needed) or morphine (15 mg sustained release every 12 hours and 5 mg every 4 hours as needed). The study duration was 4 weeks.

Results

A total of 103 patients were randomly assigned to treatment (49 in the methadone group and 54 in the morphine group). The groups had similar baseline scores for pain, sedation, nausea, confusion, and constipation. Patients receiving methadone had more opioid-related drop-outs (11 of 49; 22%) than those receiving morphine (three of 54; 6%; P = .019). The opioid escalation index at days 14 and 28 was similar between the two groups. More than three fourths of patients in each group reported a 20% or more reduction in pain intensity by day 8. The proportion of patients with a 20% or more improvement in pain at 4 weeks in the methadone group was 0.49 (95% CI, 0.34 to 0.64) and was similar in the morphine group (0.56; 95% CI, 0.41 to 0.70). The rates of patient-reported global benefit were nearly identical to the pain response rates and did not differ between the treatment groups.

Conclusion

Methadone did not produce superior analgesic efficiency or overall tolerability at 4 weeks compared with morphine as a first-line strong opioid for the treatment of cancer pain.
Pilot Study of Idarubicin-Based Intensive-Timing Induction Therapy for Children With Previously Untreated Acute Myeloid Leukemia: Children's Cancer Group Study 2941
Authors: Lange Beverly J. , Dinndorf Patricia , Smith Franklin O. , Arndt Carola , Barnard Dorothy , Feig Stephen , Feusner James , Seibel Nita , Weiman Margie , Aplenc Richard , Gerbing Robert , Alonzo Todd A.
Published: December 2003

Purpose

Randomized comparisons of idarubicin (IDA) with daunorubicin (DNR) show that in adults with acute myeloid leukemia (AML), IDA achieves higher remission rates and longer remission durations. In Children's Cancer Group Pilot Study CCG-2941, we assessed toxicity and feasibility of substituting 4 mg of DNR with 1 mg of IDA in intensive-timing daunorubicin-based induction therapy (DNR/DNR) used in CCG-2891.

Patients and Methods

On days 1 through 3 and 10 through 14, patients received two courses of dexamethasone, cytarabine, 6-thioguanine, etoposide, and IDA (IDA/IDA). After enrollment of 65 patients, toxicity prompted replacement of IDA with DNR (IDA/DNR) on days 10 through 14 for the remaining 28 patients. Outcomes were compared with those of intensive timing in CCG-2891.

Results

Treatment-related mortality after two courses of induction was not significantly different among the three regimens: 14% with IDA/IDA, 7% with IDA/DNR, and 9% with DNR/DNR. In course 1 of CCG-2941 IDA/IDA, 11% of patients withdrew compared with 1.5% in CCG-2891 (P < .001) and 5% in CCG-2941 IDA/DNR (P = not significant). Compared with CCG-2891 DNR/DRN, CCG-2941 IDA/IDA increased days in hospital (43 v 36 days; P = .007), mean duration of course 1 by a week (P = .002), and risk of grade 3 or 4 hyperbilirubinemia (18% v 5%; P = .02). Toxicity of IDA/DNR was not different from that of DNR/DNR in CCG-2891. The mean day 7 marrow blast percentage was 11.4% in CCG-2941 versus 21.1% in CCG-2891 (P = .004). Remission induction, survival, and event-free survival rates were not significantly different from those of CCG-2891.

Conclusion

In CCG-2941, excessive toxicity and withdrawals outweighed potential benefits of early response with IDA.
Combination Chemotherapy With Gemcitabine Plus Oxaliplatin in Patients With Intensively Pretreated or Refractory Germ Cell Cancer: A Study of the German Testicular Cancer Study Group
Authors: Kollmannsberger C. , Beyer J. , Liersch R. , Schoeffski P. , Metzner B. , Hartmann J.T. , Rick O. , Stengele K. , Hohloch K. , Spott C. , Kanz L. , Bokemeyer C.
Published: December 2003

Purpose

Long-term survival is rarely achieved in patients with cisplatin-refractory germ cell cancer (GCT). Both single-agent gemcitabine and oxaliplatin have shown activity in patients who experience relapse or are refractory to cisplatin treatment. This study investigates the activity of a gemcitabine plus oxaliplatin regimen in these patients.

Patients and Methods

Gemcitabine was administered at a dose of 1,000 mg/m2on days 1 and 8; oxaliplatin was administered at a dose of 130 mg/m2on day 1. Response was evaluated every 4 weeks.

Results

Thirty-five patients with a median age of 37 years (range, 21 to 54 years) were enrolled onto the study. Primary tumor localization was gonadal, retroperitoneal, or mediastinal in 30, one, and four patients, respectively. Patients had been pretreated with a median of six platinum-containing cycles (range, four to 13 cycles) and 89% of patients previously had experienced treatment failure after high-dose chemotherapy with peripheral-blood stem-cell transplantation. Sixty-three percent of patients were considered absolutely cisplatin-refractory or cisplatin-refractory. A median of two cycles (range, 1 to 6 cycles) per patient were applied. Toxicity consisted mainly of myelosuppression, with Common Toxicity Criteria grade 3 occurring in 54% of patients. Only 9% of patients developed neutropenic fever. Three patients attained a complete remission (CR), two patients attained a marker-negative partial remission, and 11 patients attained a marker-positive partial remission, resulting in an overall response rate of 46% (95% CI, 30% to 64%). All three patients with CR and one patient with a marker-negative partial remission remained disease free at 16+, 12+, 4+, and 2+ months of follow-up. Seven (44%) of these 16 responses, including one CR, occurred in cisplatin-refractory patients.

Conclusion

Gemcitabine plus oxaliplatin demonstrates antitumor activity with acceptable toxicity in heavily pretreated patients with relapsed or cisplatin-refractory GCT, and may offer a chance of long-term survival for selected patients.
Phase II Trial of Cisplatin/Etoposide and Concurrent Radiotherapy Followed by Paclitaxel/Carboplatin Consolidation for Limited Small-Cell Lung Cancer: Southwest Oncology Group 9713
Authors: Edelman Martin J. , Chansky Kari , Gaspar Laurie E. , Leigh Bryan , Weiss Geoffrey R. , Taylor Sarah A. , Crowley John , Livingston Robert , Gandara David R.
Published: December 2003

Purpose

Limited small-cell lung cancer (LSCLC) is characterized by a high initial response rate to chemoradiotherapy, but local or systemic relapse occurs in the majority of patients. Previous Southwest Oncology Group trials in LSCLC have utilized cisplatin and etoposide (PE) delivered concurrently with thoracic radiotherapy followed by two consolidation cycles. Newer chemotherapy regimens such as paclitaxel and carboplatin are active in small-cell lung cancer and hold the promise of improving both local and systemic control. S9713 evaluated the substitution of paclitaxel and carboplatin for PE consolidation in LSCLC.

Patients and Methods

Between July 1998 and August 1999, 96 patients were accrued from 43 institutions. Eighty-nine patients were eligible; 87 were assessable for survival and response. Treatment consisted of cisplatin 50 mg/m2 on days 1, 8, 29, and 36, and etoposide 50 mg/m2 on days 1 to 5 and days 29 to 33, with concurrent radiotherapy of 61 Gy beginning on day 1. Consolidation therapy was carboplatin (area under the curve = 6) and paclitaxel 200 mg/m2, both drugs administered on day 1 of a 21 day cycle for three cycles.

Results

The response rate was 86% (complete response, 33%; partial response, 53%). Median overall survival was 17 months (95% CI, 12.7 to 19.0). One- and 2-year overall survivals were 61% and 33%, respectively. Median progression-free survival (PFS) was 9 months, 1-year PFS was 40%, and 2-year PFS was 21%.

Conclusion

Consolidation therapy with paclitaxel and carboplatin in LSCLC resulted in an outcome similar to that seen in prior Southwest Oncology Group trials. This study and others which have tested paclitaxel in small-cell lung cancer dampens enthusiasm for this agent in the primary management of LSCLC.
Colon Cancer Screening Practices After Genetic Counseling and Testing for Hereditary Nonpolyposis Colorectal Cancer
Authors: Hadley Donald W. , Jenkins Jean F. , Dimond Eileen , de Carvalho Maria , Kirsch Ilan , Palmer Christina G.S.
Published: December 2003

Purpose

Hereditary nonpolyposis colorectal cancer (HNPCC) is the most common hereditary form of colon cancer. Cancer screening recommendations differ between individuals identified to carry an HNPCC mutation and those who do not carry a known family mutation. We assessed the impact of genetic counseling and testing (GCT) on the use of endoscopic screening procedures and adherence to recommended endoscopic screening guidelines in 56 asymptomatic at-risk individuals from families known to carry an HNPCC mutation.

Patients and Methods

We analyzed data on colonoscopy and flexible sigmoidoscopy screenings collected before GCT and 6 months and 12 months post-GCT on 17 mutation-positive and 39 true mutation-negative individuals. Main outcome measures were use of endoscopic screening and adherence to recommended guidelines for the relevant mutation status. Mutation status, age, sex, employment, and income were analyzed as predictor variables.

Results

Among mutation-negative individuals, use of colonoscopy and flexible sigmoidoscopy decreased significantly between pre- and post-GCT (P < .00001 and P < .0003, respectively). Among mutation-positive individuals, a nonsignificant increase (P = .24) in use was noted. Age was also associated with use of endoscopic screening after GCT (P = .03). Mutation status (odds ratio [OR], 7.5; P = .02) and employment (OR, 8.6; P = .025) were associated with nonadherence to endoscopic screening guidelines. More mutation-negative individuals strictly adhered to guidelines than did mutation-positive individuals (87% v 65%).

Conclusion

Genetic counseling and testing for HNPCC significantly influences the use of colonic endoscopy and adherence to recommendations for colon cancer screening.
Axillary Treatment in Conservative Management of Operable Breast Cancer: Dissection or Radiotherapy? Results of a Randomized Study With 15 Years of Follow-Up
Authors: Louis-Sylvestre Christine , Clough Krishna , Asselain Bernard , Vilcoq Jacques René , Salmon Remy Jacques , Campana François , Fourquet Alain
Published: December 2003

Purpose

Axillary dissection is the standard management of the axilla in invasive breast carcinoma. This surgery is responsible for functional sequelae and some options are considered, including axillary radiotherapy. In 1992, we published the initial results of a prospective randomized trial comparing lumpectomy plus axillary radiotherapy versus lumpectomy plus axillary dissection. We present an update of this study with a median follow-up of 180 months (range, 12 to 221 months).

Patients and Methods

Between 1982 and 1987, 658 patients with a breast carcinoma less than 3 cm in diameter and clinically uninvolved lymph nodes were randomly assigned to axillary dissection or axillary radiotherapy. All patients underwent wide excision of the tumor and breast irradiation.

Results

The two groups were similar for age, tumor-node-metastasis system stage, and presence of hormonal receptors; 21% of the patients in the axillary dissection group were node-positive. Our initial results showed an increased survival rate in the axillary dissection group at 5 years (P = .009). At 10 and 15 years, however, survival rates were identical in both groups (73.8% v 75.5% at 15 years). Recurrences in the axillary node were less frequent in the axillary dissection group at 15 years (1% v 3%; P = .04). There was no difference in recurrence rates in the breast or supraclavicular and distant metastases between the two groups.

Conclusion

In early breast cancers with clinically uninvolved lymph nodes, our findings show that long-term survival does not differ after axillary radiotherapy and axillary dissection. The only difference is a better axillary control in the group with axillary dissection.
Dd-STATb, aDictyosteliumSTAT protein with a highly aberrant SH2 domain, functions as a regulator of gene expression during growth and early development
Authors: Zhukovskaya, Natasha V. , Fukuzawa, Masashi , Tsujioka Masatsune , Jermyn Keith A. , Kawata Takefumi , Abe Tomoaki , Zvelebil Marketa , Williams Jeffrey G.
Published: December 2003

Dictyostelium, the only known non-metazoan organism to employ SH2 domain:phosphotyrosine signaling, possesses STATs (signal transducers and activators of transcription) and protein kinases with orthodox SH2 domains. Here, however, we describe a novel Dictyostelium STAT containing a remarkably divergent SH2 domain. Dd-STATb displays a 15 amino acid insertion in its SH2 domain and the conserved and essential arginine residue, which interacts with phosphotyrosine in all other known SH2 domains, is substituted by leucine. Despite these abnormalities, Dd-STATb is biologically functional. It has a subtle role in growth, so that Dd-STATb-null cells are gradually lost from the population when they are co-cultured with parental cells, and microarray analysis identified several genes that are either underexpressed or overexpressed in the Dd-STATb null strain. The best characterised of these,discoidin 1, is a marker of the growth-development transition and it is overexpressed during growth and early development of Dd-STATb null cells. Dimerisation of STAT proteins occurs by mutual SH2 domain:phosphotyrosine interactions and dimerisation triggers STAT nuclear accumulation. Despite its aberrant SH2 domain, the Dd-STATb protein sediments at the size expected for a homodimer and it is constitutively enriched in the nucleus. Moreover, these properties are retained when the predicted site of tyrosine phosphorylation is substituted by phenylalanine. These observations suggest a non-canonical mode of activation of Dd-STATb that does not rely on orthodox SH2 domain:phosphotyrosine interactions.
LRR-containing receptors regulating plant development and defense
Authors: Diévart Anne , Clark Steven E.
Published: December 2003

Despite the presence of more than 400 genes that encode receptor-like kinases (RLKs) in the Arabidopsis thaliana genome, very little is known about the range of biological processes that they control, or the mechanisms by which they function. This review focuses on the most recent findings from studies of several leucine-rich-repeat (LRR) class RLKs in A. thaliana, and their implications for our understanding of plant receptor function and signaling. We compare the biological functions of plant and animal LRR-containing receptors, and the potential commonalities in the signaling mechanisms employed.
Threading Intercalators as a New DNA Structural Probe
Authors: Takenaka Shigeori , Takagi Makoto
Published: December 2003

Nogalamycin is a threading intercalator and when it binds with double stranded DNA, one of the two sugar substituents goes between adjacent base pairs of DNA to form a stable complex in which the two substituents of nogalamycin are projecting out in each groove of DNA. Since the molecular volume of the substituents of nogalamycin is larger than that of the space created through the motion of DNA strands constituting the double helix, a cleavage of hydrogen bonds in the base pairs of DNA duplex is necessary to form such a complex. The structure of double-stranded DNA is dynamic, and the base pair cleavage (base pair opening) and re-formation (closing) occur frequently at ambient temperature. A wider variety of threading intercalators is obtainable synthetically, and they include several families such as 1,5-disubstituted anthraquinones, 9,10-disubstituted anthracenes, and naphthalene bis(dicarboximide) derivatives. Kinetic study of the complex formation and dissociation of naphthalene bis(dicarboximide) carrying substituents of different size have made one recognize the dynamic character of duplex DNA in intercalation reaction. A cyclic bis-intercalator was also able to form a threading complex of a catenane-like structure. A thorough study of the binding behavior of natural and synthetic threading intercalators with DNA revealed that a proper design of substituents on threading intercalators can produce ligands which specifically bind either to single- or double-stranded DNA. These ligands, synthetic ones in particular, will hopefully serve not only as new DNA structural probes but also as chemotherapeutic agents.
Energy Transfer, Electron Transfer, and Addition Reactions of Triplet State of 1,3-Dihydroimidazole-2-thiones Investigated by Laser Flash Photolysis
Authors: Alam Maksudul M , Ito Osamu
Published: December 2003

The transient absorption bands observed at ca. 400 and 550 nm for 1,3-dihydro-2H-imidazole-2-thione (IT), 1,3-dihydro-1-methyl-2H-imidazole-2-thione (MIT), and 1,3-dihydro-2H-benzimidazole-2-thione (BIT) have been assigned to their triplet states (3IT* ’s) by the quenching and sensitizing experiments using laser flash photolysis technique. Short intrinsic triplet lifetimes and relatively high triplet energies have been evaluated as characteristics of 3IT* ’s. For electron acceptors, photoinduced electron-transfer reaction occurs via 3IT* ’s in the diffusion controlled limit. The nucleophilic character of 3IT* ’s was confirmed by changing the substituents of alkenes on the addition reactions. MO calculations indicate that the lowest electronic configurations of both 3IT* and 3MIT* have 3(n,π*) character, while 3BIT* has 3(π,π*) character. The addition reactivity of 3BIT* is slightly higher than those of 3IT* and 3MIT*, which is opposite to the general tendency.
Photochemistry of Bifunctional Chain Molecules Containing Benzophenone and Anilino Chromophores. Magnetic Field and Magnetic Isotope Effects on Lifetimes of Triplet Biradicals
Authors: Nakagaki Ryoichi , Yamaoka Masaharu , Mutai Kiyoshi
Published: December 2003

The decay time of biradicals containing a benzophenone ketyl and an anilino-alkyl radical has been examined by nano-second laser photolysis in the presence of external magnetic fields up to 1 T. When sites with high spin densities are labeled with heavy carbon, noticeable magnetic isotope effects are observed on the decay kinetics for biradicals. Small kinetic effects are observed for deuterated species. The obtained results can be interpreted in terms of spin-lattice relaxation due to anisotropic hyperfine and dipole–dipole interactions. Procedures for preparing labeled species are also described.
Rate-Determining Step of Deswelling for Conventional and Macroporous Poly(N-isopropylacrylamide) Gels
Authors: Kato Norihiro , Takahashi Fujio
Published: December 2003

The kinetic parameters of deswelling for conventional and macroporous poly(N-isopropylacrylamide) gels were determined in order to point out the rate-determining step on the deswelling process in a NaCl or KCl solution. The apparent activation energy for the deswelling of the conventional gel in water (130 kJ mol−1) was larger than that of the macroporous gel in water (25 kJ mol−1). The split process of the skin layer, which was formed on the surface of the gel by heating from outside of gel, was considered concerning the rate-determining step in the case of the conventional gel. The activation entropy changes at 313 K (ΔS313’s) of the macroporous gel were determined to be −65 J K−1 mol−1 in 0.1 M NaCl (1 M = 1 mol dm−3), of which the cation exhibits a structure-forming property, and 180 J K−1 mol−1 in 0.1 M KCl, of which the cation exhibits a structure-breaking property. The sign of ΔS313 for the macroporous gel was negative at higher than 0.3 M NaCl or KCl. In order to point out the rate-determining step, the process of the salting-out effect, that of bond formation between the polymer chains, and that of forming water clusters in the presence of the cation inside of the gel are discussed.
Pressure Effect on Phase Transitions in Hexamethylbenzene Crystals
Authors: Takeshita Hideyoshi , Suzuki Yoshio , Nibu Yoshinori , Shimada Hiroko , Shimada Ryoichi
Published: December 2003

The pressure effect on the phase transitions in hexamethylbenzene and hexa(methyl-d3)benzene crystals was studied compared with the temperature effect on the phase transitions. The transition from phase II to phase III of hexa(methyl-d3)benzene crystal takes place under lower pressure than that for hexamethylbenzene crystal. The change in the spectral structure due to the intermolecular vibrations caused by an increase in the pressure indicates that the marked interaction between the intermolecular rotational vibration and the intramolecular methyl torsional vibration of hexa(methyl-d3)benzene crystal takes place under lower pressure than that for hexamethylbenzene crystal. These facts suggest that the intramolecular methyl torsional vibration plays an important role for the II-to-III phase transition in hexamethylbenzene crystals.
A Statistical Model of the Extraction-Process Parameters of Uranium–N-Phenylbenzohydroxylamine–Trioctylphosphine Oxide Complex in Chloroform Solution
Authors: Sarkar Jaya , Bag Saswati Prasad , Basumallick Amitava
Published: December 2003

The solvent extraction of uranium has been carried out with chloroform solutions of N-phenylbenzohydroxamic acid (BPHA) and Trioctylphosphine oxide (TOPO). The experiments were statistically planned to quantitatively assess the effect of the concentration of BPHA, the concentration of TOPO and the aqueous-phase pH of the solution on the percentage extraction of uranium. In addition, the interactional influence of the above-mentioned variables was also studied. A regression equation has been developed which successfully predicts the percentage extraction of uranium with the values of the variables lying between the selected range of experiments.
Structures and Electronic Spectra of Aquadiiminebis(succinimidato)copper(II) Complexes with Square Pyramidal [CuN4O] Chromophores (Diimine = 1,10-Phenanthroline and 2,2′-Bipyridine)
Authors: Akitsu Takashiro , Komorita Seiko , Kushi Yoshihiko
Published: December 2003

Copper(II) complexes [Cu(succim)2(phen)H2O]·H2O (1) (succim = succinimidate, phen = 1,10-phenanthroline) and [Cu(succim)2(bpy)H2O] (2) (bpy = 2,2′-bipyridine) were prepared and the crystal structures were determined by X-ray crystallography. The coordination geometries are found to be five-coordinated square-based pyramidal [CuN4O] for each complex. Crystal data for complex 1 are monoclinic with space group P21/n; a = 9.602(4), b = 12.003(4), c = 17.618(4) Å; β = 100.38(3)°; V = 1997(1) Å3; Z = 4. Crystal data for complex 2 are monoclinic with space group P21/n; a = 9.616(2), b = 11.616(3), c = 15.871(2) Å; β = 90.61(2)°; V = 1772.8(6) Å3; Z = 4. The axial Cu–O(water) bond distances of the present complexes (2.548(5) Å for 1 and 2.673(4) Å for 2) are appreciable longer than those of other square pyramidal trans-[CuN4O] complexes. The diffuse reflectance spectra showing a broad peak at about 17000 cm−1 were analyzed by means of Gaussian curve fitting and angular overlap model (AOM) calculations with respect to dxy, dyz, and dzx orbitals distributing in the [CuN4] basal plane. According to the analyses, transferability of AOM parameters is valid for succim. The ligand field of bpy can be described by the same parameters as py (py = pyridine). However, it is necessary to set a larger π-bonding AOM parameter for phen than that of py to reproduce the experimental results. The reason for this is out-of-plane lone pairs and π-conjugation of phen. The assignment of the one-electron orbital sequences is presumed to be dx2−y2 > dz2 > dxy > dyz > dzx based on the AOM calculations for each complex.
A New Halogen-Exchange Reaction between Sn–F and Li–X: Selective 1,2- and 1,4-Reductions of α,β-Unsaturated Ketones and Effects of Halogen Substituents on the Regioselectivity of Organotin Hydrides
Authors: Moriuchi-Kawakami Takayo , Matsuda Haruo , Shibata Ikuya , Miyatake Masato , Suwa Toshihiro , Baba Akio
Published: December 2003

We have found that halogen-exchange occurs effectively between Sn–F and Li–X (X = I, Br, Cl) in tin hydride reagents. This fact induced a complete change in the regiochemistry in the reductions of α,β-unsaturated ketones 1 with Bu2SnH2–Bu2SnF2 (Reagent A): the use of Reagent A in combination with HMPA performed 1,2-reductions, while the addition of LiI to Reagent A achieved 1,4-reductions. It was demonstrated that the regioselectivity of organotin hydrides greatly depends on the properties of the halogen substituents attached to tin atoms.
Model Studies Related to Synthesis and 1,4-Dipolar Cycloaddition Reactions of Mesoionic Heterocycles
Authors: Issac Yvette Abd El-Sayed
Published: December 2003

The reaction of 2-(substituted amino)pyridine with reactive malonic acid derivatives provided an extremely facile synthesis of the mesoionic compound 4-oxo-4H-pyrido[1,2-a]pyrimidin-1-ium-2-olates. N,N′-Disubstituted amidine reacted with diethyl malonate to afford 4-quinolone in a one-pot cyclization and rearrangement (type A/I) of 4-oxopyridiniumolate 6. The latter compound was isolated via a reaction of acyclic amidine with AME’s. A cycloaddition reaction of the mesoionic pyrimidine 6 with maleic anhydride or N-phenylmaleimide yielded [2+4] cycloadducts. Triphenyl pyrrolopyridinetrione 12 was achieved via a ring transformation of the cycloadduct 4-benzyl-3,5-dioxo-1,2,6-triphenyl-2,6-diazabicyclo[2.2.2]octane-7,8-dicarboxylic anhydride 11d. In contrast, the cycloadduct 4-ethyl derivative 11c and substituted 3,5-dioxo-1,2,6-triphenyl-2,6-diazabicyclo[2.2.2]octane-7,8-dicarboxylic N-phenylimides did not give 12 under the same reaction conditions. The mechanistic pathway for the formation of 12 was studied. Dimethyl acetylenedicarboxylate reacted with 6b,c to furnish 2-oxo-1,2-dihydropyridine-4,5-dicarboxylates.
Synthesis and Solution Conformations of Cyclo(Pro–Leu–Gly)2 and Cyclo(Pro–Leu–Gly)4
Authors: Wang Jun , Osada Satoshi , Kodama Hiroaki , Kato Tetsuo , Kondo Michio
Published: December 2003

Two cyclic peptides containing the C-terminal tripeptide sequence of oxytocin, cyclo(Pro–Leu–Gly)2 and cyclo(Pro–Leu–Gly)4, have been synthesized from the corresponding linear hexapeptide active ester under high dilution conditions. Cyclo(Pro–Leu–Gly)4 serves as an example of the synthesis of cyclic peptides from linear peptides containing an even number of amino acid residues through dimerization. These two compounds are characterized by TLC, HPLC, amino acid analysis, NMR, and mass spectra. Cyclo(Pro–Leu–Gly)2 has also been synthesized from the linear tripeptide precursor independently, and its properties have been shown to be identical to that from linear hexapeptide. Circular dichroism indicated that cyclo(Pro–Leu–Gly)2 contains β-turns as expected; in contrast, cyclo(Pro–Leu–Gly)4 exhibited a random structure pattern. The NMR spectra demonstrated that cyclo(Pro–Leu–Gly)2 is fixed in only one conformer in DMSO, while in a CDCl3 solution, several conformations with a rapid interconversion are present. Unlike the cyclohexapeptide, cyclo(Pro–Leu–Gly)4 showed more complicated NMR spectra in the two solvents; two or more conformers are considered to be present.
Osmotic Stability of Muramyl Dipeptide-Bearing Liposomes and Molecular Miscibility in Their Membranes
Authors: Kim Suhk-mann , Kiyonaga Hiroshi , Yamaguchi Hideto , Morozumi Hiroto , Fujiwara Toshimichi , Ando Shuichi , Tsuge Hideya , Akutsu Hideo
Published: December 2003

Muramyl dipeptide is the minimal and essential structural unit for the immunopotentiating activities of bacterial cell walls. The muramyl dipeptide derivative N-acetyl-6-O-(2-tetradecylhexadecanol)muramyl-l-alanyl-d-isoglutamine (B30-MDP) and its amide derivative (B30-MDPA) are good basic materials for use in artificial liposome vaccines (virosomes). The osmotic stability of muramyl dipeptide-bearing liposomes composed of various binary mixtures was examined to find conditions favoring stable liposome formation. The osmotic properties of B30-MDP-bearing and B30-MDPA-bearing liposomes were significantly different from each other. Nevertheless, a good correlation between osmotic stability and virosome formation was found for both types of liposomes. Furthermore, the dynamic structures and the intermolecular interactions of phospholipids in muramyl dipeptide-bearing liposomes were investigated by solid-state 2H and 31P NMR. The results suggested that molecular miscibility in the liposomes is not an essential factor for osmotic stability. Negative charges on the liposome surface and flexible hydrophilic moieties were found to be the most important factors in keeping isolated liposomes osmotically stable.