bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimating causal effects from multiple cycle data in studies of in vitro fertilization
Authors: Hogan Joseph W , Scharfstein Daniel O
Published: March 2006

Prospective studies of reproductive outcomes frequently record data at multiple cycles. For example, studies of in vitro fertilization and embryo transfer (IVF-ET) follow women or couples for possibly several IVF cycles and record outcomes such as pregnancy status and embryo implantation. Several time-varying covariates, such as age and diagnostic markers, typically are available as well. When attention is focused on measurement of exposure effects, the use of multiple cycle data poses several complications. If the study is observational, the exposure probability may depend on subject characteristics. Moreover, attrition rates in IVF-ET can be substantial, and the attrition process can be expected to depend heavily on prior outcome. In fact, both success (pregnancy) and failure (lack of embryo implantations) can be prognostic of dropout. In this paper, we illustrate the use of causal modeling for multiple cycle data. Key assumptions are reviewed, and inference based on weighted estimating equations is described in detail. The methods are applied to a study of the effects of hydrosalpinx among women with tubal disease undergoing IVF-ET.
Assessment of variance components in elliptical linear mixed models
Authors: Savalli Carine , Paula Gilberto A , Cysneiros Francisco JA
Published: March 2006

The aim of this article is to discuss the problem of testing variance components in elliptical linear mixed models. The elliptical class includes all symmetrical continuous distributions, such as normal, Student- t, Pearson VII, power exponential, logistic I, logistic II, and so on. An approach for elliptical linear mixed models is proposed. The estimation procedure for the fixed parameters, variance components and random effects is also presented and a score-type test for one-sided alternatives to assess the variance components is investigated. Finally, two illustrative examples are given in which normal linear mixed models are compared with elliptical linear mixed models with heavy-tailed error distributions.
Estimation in generalised linear mixed models with binary outcomes by simulated maximum likelihood
Authors: Ng Edmond SW , Carpenter James R , Goldstein Harvey , Rasbash Jon
Published: March 2006

Fitting multilevel models to discrete outcome data is problematic because the discrete distribution of the response variable implies an analytically intractable log-likelihood function. Among a number of approximate methods proposed, second-order penalised quasi-likelihood (PQL) is commonly used and is one of the most accurate. Unfortunately, even the second-order PQL approximation has been shown to produce estimates biased toward zero in certain circumstances. This bias can be marked especially when the data are sparse. One option to reduce this bias is to use Monte-Carlo simulation. A bootstrap bias correction method proposed by Kuk has been implemented in MLwiN. However, a similar technique based on the Robbins-Monro (RM) algorithm is potentially more efficient. An alternative is to use simulated maximum likelihood (SML), either alone or to refine estimates identified by other methods. In this article, we first compare bias correction using the RM algorithm, Kuk’s method and SML. We find that SML performs as efficiently as the other two methods and also yields standard errors of the bias-corrected parameter estimates and an estimate of the log-likelihood at the maximum, with which nested models can be compared. Secondly, using simulated and real data examples, we compare SML, second-order Laplace approximation (as implemented in HLM), Markov Chain Monte-Carlo (MCMC) (in MLwiN) and numerical integration using adaptive quadrature methods (in Stata’s GLLAMM and in SAS’s proc NLMIXED). We find that when the data are sparse, the second-order Laplace approximation produces markedly lower parameter estimates, whereas the MCMC method produces estimates that are noticeably higher than those from the SML and quadrature methods. Although proc NLMIXED is much faster than GLLAMM, it is not designed to fit models of more than two levels. SML produces parameter estimates and log-likelihoods very similar to those from quadrature methods. Further our SML approach extends to handle other link functions, discrete data distributions, non-normal random effects and higher-level models.
Conservation encounters: transculturation in the ‘contact zones’ of empire
Authors: Sundberg Juanita
Published: March 2006

In the last 20 years, Latin American countries have experienced a boom in conservation territories. At the same time, neoliberal restructuring of Latin American economies has devolved funding and management responsibilities to international NGOs. In this context, conservation projects have become important zones of encounter and contact, wherein those inhabiting protected areas are necessarily subject to and subjected by the discourses and practices of conservation institutions. How do local actors engage with these processes? This paper examines the cultural politics of conservation encounters in the Maya Biosphere Reserve, a protected area in Guatemala's northern department of Petén. Drawing upon the concept of transculturation and anti–essentialist framings of subject formation as performative, I outline how differently situated social groups in the reserve negotiate, contest and enact the daily discourses and practices of conservation as articulated by powerful US based international organizations.
Spectacle, architecture and place at the Nuremberg Party Rallies: projecting a Nazi vision of past, present and future
Authors: Hagen Joshua , Ostergren Robert
Published: March 2006

Nuremberg, perhaps more than any other place, stands central among iconic images of Nazi Germany. The Nazi regime went to great lengths to inscribe its basic tenets into Nuremberg's urban landscape. While many are already familiar with the role Nuremberg played as the site of the annual Nazi Party Rallies, few realize that the Nazi building programme in Nuremberg placed great emphasis on redesigning the city's historical centre in addition to developing the extensive rally grounds on the city's edge. This article explores the architectural form, performative function and motivating ideologies associated with these extensive building programmes in Nuremberg and, rather than seeing them as two separate projects, highlights the intimate connections between the construction of the rally grounds on the city's edge and the concurrent redesign of the city's historical centre. Although seemingly irreconcilable in terms of style and scale, these efforts to build and rebuild in Nuremberg were actually seen as complementing elements in the regime's programme to create and project images of historical greatness, current political legitimacy and promises of future grandeur.
Sydney's SoHo Syndrome? Loft living in the urbane city
Authors: Shaw Wendy S.
Published: March 2006

In its ongoing search for a global identity, the city of Sydney, Australia, has looked to other cities for inspiration and direction. Like many of these cities, Sydney's Central Business District, and the former industrial areas that surround it, are being transformed through ‘apartment’ (condominium) development. Many are marketed as ‘New York–style lofts’ via a flurry of promotions that suggest a distinctly generic and global form of cosmopolitan urbanism. The essay details how this recent spate of Manhattanization rests not only on a cache of historically embedded Manhattan imaginaries, but on localized socio–cultural moments that are part of Sydney's particular experience of SoHo Syndrome. Tracing the pathways to Sydney's version of the global phenomenon of loft living has enabled a deeper understanding of the city's evolving built and cultural landscapes.
The rhetoric of nostalgia: postcolonial Alexandria between uncanny memories and global geographies
Authors: Dora Veronica Della
Published: March 2006

Memory, nostalgia and place are subjects of increasing scholarly interest. While invoked by cultural geographers as a ‘productive force’ moulding urban landscape, nostalgia often remains an unexamined, a priori concept. Through the exploration of different reactions to the spatialized history of postcolonial Alexandria, I consider nostalgia as a fluid, multifaceted, and performative force operating at different scales and levels: on one hand, an unconscious phenomenon in the years following Egyptian nationalization, intertwining with the uncanny and bringing to surface ‘unwanted’ memories; on the other, a powerful device increasingly exploited by urban developers and the state for the construction of a ‘cosmopolitan memory’. While the former kind of nostalgia presents itself as an effective counterpart to the colonial ‘cartographic gaze’, the latter responds to the logics of cultural consumption, and constitutes a strategy adopted in an increasing number of former cosmopolitan cities seeking to negotiate a position within the global capitalist economy.
‘Subject to control’: shifting geographies of race and labour in US sugar agroindustry, 1930–1950
Authors: Hollander Gail M.
Published: March 2006

This article analyses how processes of racialization and place making converged in south Florida as the region's sugar agroindustry shifted from a southern US to a Caribbean labour market. The article engages theoretically at the intersection of the literatures on the geographies of race and labour, paying particular attention to ideas about the role of the state in each. I argue that such an engagement not only enhances the collective analytical power of such approaches, but that it is also critical for understanding agroindustry labour practices in south Florida. The empirical materials used include historical documents, reports and publications of the US Government and the United States Sugar Corporation (USSC). The analysis shows how ideas of corporate paternalism and industrial managerialism promoted by USSC were melded to an agricultural enterprise embedded in the racism of the Jim Crow South and the history of plantation slavery. The contradictions between USSC's dependence on cheap labour disciplined by Jim Crow violence and its corporate paternalism would never be fully reconciled and ultimately would prove untenable. As a consequence, sugar industry investors in collaboration with state labour regulators reimagined the ideal cane worker, elaborating intraracial categories of black labour based on place of origin. As the geography of labour markets was rescaled to the international level, the primary mechanism of labour control shifted from Jim Crow to summary deportation of foreign black workers from the Caribbean. This study contributes to our understanding of how historic processes of racialization are bound together with the political and economic processes of regional agroindustrial development.
Contentment With Quality of Life Among Breast Cancer Survivors With and Without Contralateral Prophylactic Mastectomy
Authors: Geiger Ann M. , West Carmen N. , Nekhlyudov Larissa , Herrinton Lisa J. , Liu In-Liu A. , Altschuler Andrea , Rolnick Sharon J. , Harris Emily L. , Greene Sarah M. , Elmore Joann G. , Emmons Karen M. , Fletcher Suzanne W.
Published: March 2006

Purpose

To understand psychosocial outcomes after prophylactic removal of the contralateral breast in women with unilateral breast cancer.

Methods

We mailed surveys to women with contralateral prophylactic mastectomy after breast cancer diagnosis between 1979 and 1999 at six health care delivery systems, and to a smaller random sample of women with breast cancer without the procedure. Measures were modeled on instruments developed to assess contentment with quality of life, body image, sexual satisfaction, breast cancer concern, depression, and health perception. We examined associations between quality of life and the other domains using logistic regression.

Results

The response rate was 72.6%. Among 519 women who underwent contralateral prophylactic mastectomy, 86.5% were satisfied with their decision; 76.3% reported high contentment with quality of life compared with 75.4% of 61 women who did not undergo the procedure (P = .88). Among all case subjects, less contentment with quality of life was not associated with contralateral prophylactic mastectomy or demographic characteristics, but was associated with poor or fair general health perception (odds ratio [OR], 7.0; 95% CI, 3.4 to 14.1); possible depression (OR, 5.4; 95% CI, 3.1 to 9.2); dissatisfaction with appearance when dressed (OR, 3.5; 95% CI, 2.0 to 6.0); self-consciousness about appearance (OR, 2.0; 95% CI, 1.1 to 3.7); and avoiding thoughts about breast cancer (modest: OR, 2.2; 95% CI, 1.1 to 4.5; highest: OR, 1.7; 95% CI, 0.9 to 3.2).

Conclusion

Most women undergoing contralateral prophylactic mastectomy report satisfaction with their decision and experience psychosocial outcomes similar to breast cancer survivors without the procedure.
Incidence, Risk Factors, and Outcomes of Catheter-Related Thrombosis in Adult Patients With Cancer
Authors: Lee Agnes Y.Y. , Levine Mark N. , Butler Gregory , Webb Carolyn , Costantini Lorrie , Gu Chushu , Julian Jim A.
Published: March 2006

Purpose

Thrombosis of long-term central venous catheters (CVC) is a serious complication that causes morbidity and interrupts the infusion of chemotherapy, intravenous medication, and blood products. We performed a prospective study to examine the incidence, risk factors, and long-term complications of symptomatic catheter-related thrombosis (CRT) in adults with cancer.

Patients and Methods

Consecutive patients with cancer, undergoing insertion of a CVC, were enrolled and prospectively followed while their catheter remained in place plus 4 subsequent weeks or a maximum of 52 weeks, whichever came first. Patients with symptomatic CRT were followed for an additional 52 weeks from the date of CRT diagnosis. The end points were symptomatic CRT, symptomatic pulmonary embolism (PE), postphlebitic syndrome, and catheter life span.

Results

Over 76,713 patient-days of follow-up, 19 of 444 patients (4.3%) had symptomatic CRT in 19 of 500 catheters (0.3 per 1,000 catheter-days). The median time to CRT was 30 days and the median catheter life span was 88 days. Significant baseline risk factors for CRT were: more than one insertion attempt (odds ratio [OR] = 5.5; 95% CI, 1.2 to 24.6; P = .03); ovarian cancer (OR = 4.8; 95% CI, 1.5 to 15.1; P = .01); and previous CVC insertion (OR = 3.8; 95% CI, 1.4 to 10.4; P = .01). Nine of the 19 CRT patients were treated with anticoagulants alone, eight patients were treated with anticoagulants and catheter removal, while two patients did not receive anticoagulation. None had recurrent CRT or symptomatic PE. Postphlebitic symptoms were infrequent.

Conclusion

In adults with cancer, the incidence of symptomatic CRT is low and long-term complications are uncommon.
Randomized Phase II Trial of Matrix Metalloproteinase Inhibitor COL-3 in AIDS-Related Kaposi's Sarcoma: An AIDS Malignancy Consortium Study
Authors: Dezube Bruce J. , Krown Susan E. , Lee Jeannette Y. , Bauer Kenneth S. , Aboulafia David M.
Published: March 2006

Purpose

Matrix metalloproteinases (MMPs) are involved in tumor metastasis and are overexpressed in Kaposi's sarcoma (KS) cells. In a phase I trial of the MMP inhibitor COL-3 in patients with AIDS-related KS, the drug was well tolerated, KS regression was observed, and MMP-2 levels decreased significantly in responders compared with nonresponders. The aim of this trial was to extend these initial observations.

Patients and Methods

This was a randomized, parallel-group, phase II study. COL-3 was administered orally once daily at one of two doses (group A received 50 mg and group B received 100 mg) to patients with AIDS-related KS. Antiretroviral therapy was permitted but not required. Serial tumor assessments and plasma levels of MMPs were obtained. Study end points were progressive KS and recurrent dose-limiting toxicity.

Results

Seventy-five patients received COL-3: 37 in group A and 38 in group B. Fifty-seven patients (76%) had received prior KS therapy. Thirty-three patients (44%) had more than 50 KS lesions. The response rate in group A was 41%, which was significantly greater than the prespecified target rate of 20% (95% CI, 25% to 58%; P = .003); the response rate of group B was 29% (P = not significant). There were significant declines in MMP-2 and MMP-9 plasma levels from baseline to minimum value with treatment (MMP-2, P < .001; MMP-9, P = .001). The most common adverse events were photosensitivity and rash.

Conclusion

COL-3, when administered as 50 mg/d, is both active and well tolerated in the treatment of AIDS-related KS. COL-3 is a promising agent for the treatment of this opportunistic neoplasm of AIDS.
Differential CD146 Expression on Circulating Versus Tissue Endothelial Cells in Rectal Cancer Patients: Implications for Circulating Endothelial and Progenitor Cells As Biomarkers for Antiangiogenic Therapy
Authors: Duda Dan G. , Cohen Kenneth S. , di Tomaso Emmanuelle , Au Patrick , Klein Rachael J. , Scadden David T. , Willett Christopher G. , Jain Rakesh K.
Published: March 2006

Purpose

Circulating endothelial cells (CECs) and progenitor cells are currently evaluated as potential biomarkers of antiangiogenic therapy. CD146 is considered a panendothelial-specific marker, but its utility as a CEC marker in cancer patients remains unclear.

Patients and Methods

We analyzed the expression of CD146 on mononuclear blood cells, primary tissue endothelial cells, and malignant and normal tissues by flow cytometric and immunohistochemical analyses. Furthermore, we measured the circulation kinetics of CD146+ cells before, and then 3 and 12 days after vascular endothelial growth factor (VEGF) antibody blockade by bevacizumab infusion in rectal cancer patients enrolled in a phase I trial.

Results

In the peripheral blood of these cancer patients, over 90% of the CD146+ cells were CD45+ hematopoietic cells. CD146 expression was primarily detected on a subset of CD3+CD4+ lymphocytes, and was undetectable on CD34+CD133+CD45dim progenitor cells or CD31brightCD45− viable CECs. In contradistinction, CD146 was detectable in tissues on both cellular components of tumor vessel wall: CD31brightCD45− endothelial cells and α-SMA+ pericytes. Unlike viable CECs and progenitor cells, CD146+ cell concentration in the peripheral blood of cancer patients did not decrease during VEGF blockade.

Conclusion

CD146 is fairly homogeneously expressed on vascular endothelium but not on viable CECs or progenitor cells. The vast majority of CD146+ blood cells are lymphocytes, and VEGF blockade by bevacizumab did not significantly change their number in rectal cancer patients. These results underscore the need for further characterization and identification of new markers for CEC subpopulations for their development as biomarkers of antiangiogenic therapy.
Pretreatment CA-125 and Risk of Relapse in Advanced Ovarian Cancer
Authors: Markman Maurie , Liu P.Y. , Rothenberg Mace L. , Monk Bradley J. , Brady Mark , Alberts David S.
Published: March 2006

Purpose

A previous report suggested the nadir serum CA-125 level within the group of patients with ovarian cancer who achieved normalization of CA-125 accurately defined the risk of relapse. Using similar CA-125 subgroups, we sought to determine if the baseline CA-125 level before initiation of maintenance chemotherapy in women achieving a clinically-defined complete response to primary chemotherapy would be of prognostic value.

Patients and Methods

Patients included in this retrospective analysis had been treated on one of two previously reported trials of maintenance chemotherapy (three v 12-monthly cycles of paclitaxel; oral altretamine), with a baseline CA-125 level of ≤ 35 u/mL. Progression-free survival (PFS) from study entry was analyzed by the Cox regression model.

Results

The distribution of premaintenance baseline CA-125 levels for the 384 patients was 58%, 34%, and 8% for values of (A) ≤ 10 u/mL, (B) 11 to 20 u/mL, and (C) 21 to 35 u/mL, respectively. The baseline CA-125 was highly statistically significant, either as a categoric variable (P < .001) or as a continuous variable (P < .0001). Median PFS was 24 months, 17 months, and 7 months for groups (A), (B), and (C), respectively. There was no evidence the CA-125 effect differed by trial or treatment in an interaction analysis (P = .70).

Conclusion

The baseline CA-125 level before initiation of maintenance chemotherapy strongly predicts the risk of subsequent relapse. Patients with premaintenance baseline CA-125 values ≤ 10 u/mL have a superior PFS compared with higher levels in the normal CA-125 range.
Glucuronidation oftrans-resveratrol by human liver and intestinal microsomes and UGT isoforms
Authors: Brill Shirley S , Furimsky Anna M , Ho Mark N , Furniss Michael J , Li Yi , Green Adam G , Green Carol E , Iyer Lalitha V , Bradford Wallace W , Kapetanovic Izet M
Published: March 2006

Resveratrol (trans-resveratrol, trans-3,5,4′-trihydroxystilbene) is a naturally occurring stilbene analogue found in high concentrations in red wine. There is considerable research interest to determine the therapeutic potential of resveratrol, as it has been shown to have tumour inhibitory and antioxidant properties. This study was performed to investigate the glucuronidation of resveratrol and possible drug interactions via glucuronidation. Two glucuronide conjugates, resveratrol 3-O-glucuronide and resveratrol 4′-O-glucuronide, were formed by human liver and intestinal microsomes. UGT1A1 and UGT1A9 were predominantly responsible for the formation of the 3-O-glucuronide (Km = 149 μm) and 4′-O-glucuronide (Km = 365 μm), respectively. The glucuronide conjugates were formed at higher levels (up to 10-fold) by intestinal rather than liver microsomes. Resveratrol was co-incubated with substrates of UGT1A1 (bilirubin and 7-ethyl-10-hydroxycamptothecin (SN-38)) and UGT1A9 (7-hydroxytrifluoromethyl coumarin (7-HFC)). No major changes were noted in bilirubin glucuronidation in the presence of resveratrol. Resveratrol significantly inhibited the glucuronidation of SN-38 (Ki = 6.2 ± 2.1 μm) and 7-HFC (Ki = 0.6 ± 0.2 μm). Hence, resveratrol has the potential to inhibit the glucuronidation of concomitantly administered therapeutic drugs or dietary components that are substrates of UGT1A1 and UGT1A9.
Participation of the spinal TRPV1 receptors in formalin-evoked pain transduction: a study using a selective TRPV1 antagonist, iodo-resiniferatoxin
Authors: Kanai Yoshihito , Hara Tomokazu , Imai Aki
Published: March 2006

The involvement of spinal transient receptor potential vanilloid 1 (TRPV1) in formalin-evoked pain has remained unclear, because investigation of this kind of pain with selective antagonists has not been conducted. The purpose of this study is to investigate the participation of spinal TRPV1 in formalin-evoked pain with iodo-resiniferatoxin (I-RTX), a potent TRPV1-selective antagonist. I-RTX given intrathecally dose-dependently and significantly decreased the number of flinching responses in the formalin-evoked 1st and 2nd phase with ID50 values (drug dose producing 50% inhibition of response) of 1.0 and 3.8 μg, respectively, and concentration-dependently suppressed capsaicin-evoked calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) release from rat spinal cord slices with an IC50 value (drug concentration producing 50% inhibition of response) of 86 nm. Capsazepine, a classical non-selective TRPV1 antagonist, given intrathecally also inhibited formalin-evoked flinching in both the 1st and 2nd phase with ID50s of 420 and 200 μg, respectively, and CGRP-LI release from rat spinal cord slices with an IC50 of 7.8 μm. Ratios of in-vivo analgesic potencies of I-RTX and capsazepine well reflected their intrinsic in-vitro activity. These findings suggest that spinal TRPV1 participates in the transduction system of formalin-evoked pain.
Induction of cytochrome P450-dependent monooxygenase by extracts of the medicinal herbSalvia miltiorrhiza
Authors: Lin Yun-Lian , Don Ming-Jaw , Kuo Ya-Hui , Chen Ruei-Ming , Ueng Yune-Fang
Published: March 2006

The herbal medicine Salvia miltiorrhiza (Danshen) is currently used for the treatment of cardiovascular and cerebrovascular diseases. To assess possible herb-drug interactions, the effects of the aqueous and ethyl acetate extracts of S. miltiorrhiza on cytochrome P450 (CYP) were studied. Oral treatment of C57BL/6J mice with the ethyl acetate extract caused a dose-dependent increase in liver microsomal 7-methoxyresorufin O-demethylation (MROD) activity. The ethyl acetate extract caused an 8-, 2-, 3- and 3-fold increase in hepatic MROD, tolbutamide hydroxylation, nifedipine oxidation and warfarin 7-hydroxylation activity, respectively. However, the aqueous extract had no effects on any of the activities determined. Pharmaceutical product of S. miltiorrhiza extract caused a dose-dependent increase in MROD activity without affecting other activity. Immunoblot analysis of microsomal proteins showed that ethyl acetate extract-treatment elevated the protein levels of CYP1A and CYP3A. Tanshinone IIA was the main diterpene quinone in S. miltiorrhiza. At the dose corresponding to its content in ethyl acetate extract, tanshinone IIA-treatment increased mouse liver microsomal MROD activity. These results demonstrated that there were mouse CYP1A, CYP2C and CYP3A-inducing agents present in the ethyl acetate extract, but not in the aqueous extract, of S. miltiorrhiza. Tanshinone IIA played a role in the induction of CYP1A by S. miltiorrhiza. The CYP induction by the ethyl acetate extract and pharmaceutical product suggested that possible drug interactions between S. miltiorrhiza and CYP substrates should be noticed.
Activity of the Chinese prescription Hachimi-jio-gan against renal damage in the Otsuka Long-Evans Tokushima Fatty rat: a model of human type 2 diabetes mellitus
Authors: Yamabe Noriko , Yokozawa Takako
Published: March 2006

Currently, in Japan, approximately 95% of patients with diabetes mellitus have non-insulin-dependent (type 2) diabetes mellitus (NIDDM), and diabetic nephropathy is a major cause of patients requiring chronic haemodialysis. A previous study showed that Hachimi-jio-gan has a protective effect in rats subjected to subtotal nephrectomy plus streptozotocin injection, a model of insulin-dependent (type 1) diabetic nephropathy. In this study, we used the Otsuka Long-Evans Tokushima Fatty (OLETF) rat, a model of human NIDDM, to investigate whether long-term administration of Hachimi-jio-gan affects glycaemic control and renal function in NIDDM. Male OLETF rats, aged 22 weeks, were divided into 4 groups of 10 and given Hachimi-jio-gan (50, 100 or 200 mg kg−1 daily) orally or no treatment for 32 weeks. Male Long-Evans Tokushima Otsuka (LETO) rats (n = 6) were used as non-diabetic normal controls. Hachimi-jio-gan reduced hyperglycaemia dose-dependently from 16 weeks of the administration period. Urinary protein excretion decreased significantly from an early stage, and creatinine clearance levels improved at 32 weeks. In addition, the levels of serum glycosylated protein and renal advanced glycation end-products were effectively reduced. Hachimi-jio-gan also significantly reduced the levels of thiobarbituric acid-reactive substances in renal mitochondria, although it showed only a tendency to reduce these in serum. Furthermore, long-term administration of Hachimi-jio-gan reduced renal cortical expression of proteins, such as transforming growth factor-β1 (TGF-β1), fibronectin, inducible nitric oxide synthase and cyclooxygenase-2. The 100- and 200-mg kg−1 daily doses of Hachimi-jio-gan significantly reduced TGF-β1 and fibronectin protein expression to levels below those of LETO rats. These data suggest that Hachimi-jio-gan may have a beneficial effect on the progression of diabetic nephropathy in OLETF rats by attenuating glucose toxicity and renal damage.
Changes in brain biogenic amines and haem biosynthesis and their response to combined administration of succimers and Centella asiatica in lead poisoned rats
Authors: Saxena Geetu , Flora S J S
Published: March 2006

This study was designed to investigate the therapeutic potential of meso 2,3-dimercaptosuccinic acid (DMSA) and one of its monoesters, monoisoamyl DMSA (MiADMSA), individually or when administered in combination with an extract of Centella asiatica against experimental lead intoxication in rats. Biochemical variables indicative of alterations in the central nervous system and haem biosynthesis were investigated to determine the toxicity in male Wistar rats. Thirty five rats were exposed to 0.2% lead acetate for 10 weeks, followed by 10 days of treatment with DMSA and MiADMSA (50 mg kg−1, i.p., once daily) alone and in combination with C. asiatica (200 mg kg−1, p.o., once daily). Biochemical variables indicative of oxidative stress and brain biogenic amines, along with lead concentration in blood and brain, were measured. Lead exposure caused a significant depletion of blood and brain δ-aminolevulinic acid dehydratase (ALAD) activity, an important enzyme of the haem biosynthesis pathway, and glutathione (GSH) level. These changes were accompanied by a marked increase in reactive oxygen species (ROS) level, thiobarbituric acid reactive substances (TBARS), δ-aminolevulinic acid synthase (ALAS) and oxidized glutathione (GSSG) activity in blood and brain. Significant depletion of brain noradrenaline (norepinephrine, NE), 5-hydroxytryptamine (5-HT), dopamine (DA) and acetylcholinesterase (AChE) also were observed following lead exposure. Also seen was a significant depletion in brain glutathione peroxidase (GPx), glutathione S-transferase (GST) and monoamine oxidase activity, as well as blood and brain superoxide dismutase (SOD) activity. These biochemical changes were correlated with an increased uptake of lead in blood and brain. Combined administration of MiADMSA and C. asiatica was most effective in reducing these alterations, including biogenic amines, besides reducing body lead burden, compared with individual treatment with MiADMSA. Certain other biochemical variables responded favourably to combination therapy and monotherapy with MiADMSA. Thus, supplementation of C. asiatica during chelation could be recommended for achieving optimum effects of chelation therapy.
Antioxidant properties of propargylamine derivatives: assessment of their ability to scavenge peroxynitrite
Authors: Dragoni Stefania , Porcari Valentina , Valoti Massimo , Travagli Massimo , Castagnolo Daniele
Published: March 2006

A series of arylpropargylamines, variously substituted in the hydrogen in p-position and in the propargyl moiety, were studied as potential peroxynitrite scavengers. The scavenging activity of these compounds was evaluated through peroxynitrite (ONOO−)-mediated oxidation of dichlorofluorescin and linoleic acid by measuring the dichlorofluorescein formation and oxygen consumption, respectively. Among tested compounds, only 1-phenylpropargylamine (AP3) promoted concentration-dependent inhibition of ONOO−-induced dichlorofluorescin and linoleic acid oxidation with IC50 values of 637 and 63 μm, respectively. The AP3 spectral changes in UV-visible absorbance properties in the presence of peroxynitrite suggested the formation of a new compound. This was identified by gas-chromatograph-mass spectrometer analysis as phenylpropargyl alcohol. Structure—activity relationship analysis indicated that the scavenging activity of AP3 was due to the aminopropargyl moiety and availability of the nitrogen electron pair. This data suggested that AP3 could be considered a lead compound for the synthesis of new ONOO− scavenger derivatives.
An Efficient Synthesis of Unsymmetrical Sulfides from Organic Disulfides and Aromatic Compounds
Authors: Mukaiyama Teruaki , Suzuki Kaoru
Published: March 2006

In the presence of an active acidic catalyst generated from SbCl5 and AgSbF6, the sulfenylation reaction of aromatic compounds with organic disulfides smoothly proceeds in refluxing 1,2-dichloroethane to afford the corresponding unsymmetrical sulfides in high yields.
Solvent Effects on an Enzymatic Ester Synthesis in Supercritical Carbon Dioxide
Authors: Ikushima Yutaka , Saito Norio , Yokoyama Toshirou , Hatakeda Kiyotaka , Ito Shota , Arai Masahiko , Blanch Harvey W
Published: March 2006

The ester synthesis from oleic acid and (±)-citronellol by lipase was carried out in supercritical carbon dioxide(SC-CO2). In the near-critical region, the rate of reaction was considerably enhanced and (S)-(−)-oleic acid 3,7-dimethyl-6-octenyl ester was stereoselectively formed. The results were discussed with taking account of solvent properties of SC-CO2 and aggregation phenomenon about reacting species at high pressures.
Porphyrin Synthesis in Clay Nanospaces
Authors: Onaka Makoto , Shinoda Tomotaka , Izumi Yusuke , Nolen Ernest
Published: March 2006

meso-Tetraalkylporphyrins were synthesized in good yields from aliphatic aldehydes and pyrrole by using the clay, montmorillonite K10. The nanometer size porous structures of K10 provide suitable reaction media for polymerization-cyclization condensations of aldehyde and pyrrole.
Generation of a Cation Radical from 2-Pivaloyl-1-tributylstannyl-1,2,3,4-tetrahydroisoqumoline and the Reaction with Carbon Nucleophiles
Authors: Narasaka Koichi , Kohno Yasushi , Shimada Satoru
Published: March 2006

Oxidation of 2-pivaloyl-1-tributylstannyl-1,2,3,4-tetrahydroisoquinoline with metallic oxidants generates a reactive species such as the hydroisoquinolin-1-yl cation by eliminating the stannyl group. This intermediate reacts with various carbon nucleophiles to give the corresponding addition products.
Rose-Bengal-Sensitized Photooxidation of Quadricyclane. A [2σ+2σ+2π] Cycloaddition of Singlet Oxygen
Authors: Hatsui Toshihide , Takeshita Hitoshi
Published: March 2006

Quadricyclane was photooxygenated with singlet oxygen generated under Rose-Bengal-sensitized conditions to a dioxetane, which in turn gave 2-cyclopentene-1,4-dicarbaldehyde and 5-norbornene-cis-2,3-exo-diol. For the mechanism to form the dioxetane, an involvement of a [2σ+2σ+2π] electrocyclic process is proposed.
A Novel and Very Active “Vanadium-based” Metathesis Catalyst. The Metathesis of Alkenes over SnMe4-V2O5/Al2O3
Authors: Ahn Ho-Geun , Yamamoto Kei , Nakamura Ryuichi , Niiyama Hiroo
Published: March 2006

The first successful vanadium-based catalyst system for olefin metathesis was found as SnMe4-V2O5/Al2O3, which was prepared by depositing SnMe4 on V2O5/Al2O3 preheated at high temperatures. The catalytic activity of the new system greatly depended on the loading of SnMe4 and also on the composition and pretreatment temperature of V2O5/Al2O3.
Evidence for Parallel Photoinduced Electron Transfer in Diqumone Substituted Porphyrins
Authors: Borovkov Victor V , Ishida Akito , Takamuku Setsuo , Sakata Yoshiteru
Published: March 2006

Fluorescence spectra and decay kinetics of diqumone substituted porphynns were examined in a comparison with those of monoquinone substituted porphynns. Fluorescence quenching of the diquinone molecules is larger than that of the monoquinones and the electron-transfer rate constants of the diquinones are larger than those of the monoquinones by a factor of two regardless of the rigidity of the spacer groups indicating the existence of the parallel electron-transfer mechanism in diquinones.
Electrochemical Properties of Copper Proteins, Pseudoazurin and Nitrite Reductase from Achromobacter cycloclastes IAM 1013
Authors: Kohzuma Takamitsu , Takase Seiji , Shidara Sohsuke , Suzuki Shinnichiro
Published: March 2006

Voltammetric response of Achromobacter pseudoazurin at a bis(4-pyridyl)disulfide modified gold electrode shows the quasi-reversible electron transfer process, and the current due to catalytic intermolecular electron transfer reaction between Achromobacter pseudoazurin and nitrite reductase was observed in the presence of excess nitrite as the substrate.
Substituent Effects on Redox Potentials of Novel Amphoteric Terphenoquinone Analogues. Unsymmetrically Substituted 2,5-Bis(4-oxo-2,5-cyclohexadien-1-ylidene)-2,5-dihydrothiophenes
Authors: Takahashi Kazuko , Sakai Takashi
Published: March 2006

The unsymmetrically substituted derivatives of the title heterocycle-extended quinone have been synthesized and the substituents effects on their electrochemical properties have been investigated. The first reduction potentials and the first oxidation potentials correlate well with the Hammett Σσp and Σσp+ constants of the substituents, respectively.
Deprotection of Acetals and Silyl Ethers by DDQ. Is DDQ a Neutral Catalyst?
Authors: Oku Akira , Kinugasa Motoharu , Kamada Tohru
Published: March 2006

2,3-Dichloro-5,6-dicyano-p-benzoquinone (DDQ) in wet ethyl acetate at room temperature catalytically hydrolyzed acyclic acetals effectively and selectively among ethereal functional groups such as dioxoranes, 1,3-dioxanes, oxiranes, TMS- and TBDMS ethers. The mechanism is discussed on the basis of the function of DDQ as a Lewis acid in a wet solvent.
Stereoselective Synthesis of 1,2-cis-N-Glycosides by the N-Bromosuccinimide Promoted Reaction of Thioglycosides with Silylated Pyrimidme Bases
Authors: Sugimura Hideyuki , Muramoto Ikuyo , Nakamura Tadashi , Osumi Kenji
Published: March 2006

The coupling of O-benzylated 1-thioglycosides, derived from d-glucose, d-mannose, d-ribose, d-xylose, and d-arabinose, with silylated pyrimidme bases by activation with N-bromosuccinimide uniformly afforded the corresponding 1,2-cis-N-glycosides with good selectivity.
Chemisorbed Species of Alkyl Benzoates on Alumina Surface Studied by Inelastic Electron Tunneling Spectroscopy
Authors: Kamata Satsuo , Higo Morihide , Hida Atsushi
Published: March 2006

Vibrational spectra of alkyl benzoates dissociatively adsorbed on the alumina surfaces have been measured by inelastic electron tunneling spectroscopy. The analyses of the spectra indicate that ethyl and tert-butyl benzoates are adsorbed as ethoxide or benzoate ions, respectively, by the acid-catalyzed reaction on alumina surfaces.
Photochemical Reaction of Allyl-1,4-benzoquinones. Trapping of Biradical Intermediates with Olefins
Authors: Iwamoto Hidetoshi , Takuwa Akio
Published: March 2006

Irradiation of 2-allyl- and 2-(2-methylallyl)-5-methyl-1,4-benzoquinones in the presence of olefins gave tricyclic compounds in fair yields, which were the coupling products between the olefins and the biradical intermediate generated by the intramolecular photocyclization reaction of the quinone.
The Simplest Structure of the Hydrogen-Bonded Mesogen Built from 4-Alkoxybenzoic Acid and 4-Alkylpyridine
Authors: Fukumasa Mitsuo , Kato Takashi , Uryu Toshiyuki , Fréchet Jean M J
Published: March 2006

Newly designed hydrogen-bonded liquid crystals having the simplest mesogenic structure have been obtained by self-assembly of 4-alkoxybenzoic acid and 4-alkylpyridine. The complexes show nematic phases near room temperature. The nematic phase is broadened by mixing of several complexes within a homologous series.
Mixed Chromium(III)-Ruthenium(III) Trinuclear Complex, [CrRu2(μ3-O)(μ-CH3COO)6(pyridine)3]+
Authors: Sasaki Yoichi , Yoshida Yukihiro , Ohto Akihiro , Tokiwa Ayako , Ito Tasuku , Kobayashi Hanako , Uryû Norikiyo , Mogi Iwao
Published: March 2006

A mixed Cr-Ru trinuclear complex [CrRu2(μ3-O)(μ-CH3COO)6(py)3]+ has been prepared, which is the first example of mixing two metal ions of both different rows and groups into the trinuclear unit. Its magnetic and redox behavior indicate that d3 Cr(III) ion acts as if isolated ion, and that two d5 Ru(III) ions are effectively coupled while the Cr-Ru interaction is less significant as compared with the Ru-Ru one.
Electrocatalytic Oxidative Coupling Reaction of Naphthols and Naphthol Ethers on a TEMPO Modified Graphite Felt Electrode
Authors: Kashiwagi Yoshitomo , Ono Hiroaki , Osa Tetsuo
Published: March 2006

2-Naphthol and 2-methoxynaphthalene were quantitatively oxidized to the corresponding 1,1′-binaphthyls in more than 90% current efficiency on a graphite felt electrode coated with a thin poly(acrylic acid) layer immobilizing 4-amino-2,2,6,6-tetramethylpiperidinyl-1-oxyl (4-amino-TEMPO). 1-Naphthol and 1-methoxynaphthalene were also completely converted to the predicted 1,1′-, 1,2′-, and 2,2′- positioned coupling products. The reaction proceeds via electrocatalytic oxidation of the modified-TEMPO species. The electrode was not inactivated during electrolysis and could be used repeatedly.
Uptake of Carbon Monoxide by a Sulfur-Bridged Molybdenum-Nickel Cluster. Synthesis and Structure of [Mo3NiS4(CO)(H2O)9]4+
Authors: Shibahara Takashi , Mochida Shin’ichi , Sakane Genta
Published: March 2006

The molybdenum-nickel cubane-type cluster [Mo3NiS4(H2O)10]4+ uptakes carbon monoxide in dilute HCl to give a new cluster [Mo3NiS4(CO)(H2O)9]4+. The X-ray structure analysis verified that the nickel atom has a tetrahedral configuration surrounded by one CO and three S’s neglecting three Ni-Mo bonds.
Novel Stereoselective Preparation and Conformational Analysis of Furanose-Type Phosphono Sugar C-Glycosides
Authors: Yabui Akihiro , Yamashita Mitsuji , Oshikawa Tatsuo , Hanaya Tadashi , Yamamoto Hiroshi
Published: March 2006

Treatment of 1-alkoxy-3-phospholene 1-oxide with lithium diisopropylamide followed by novel stereoselective C-alkylation with alkyl halides afforded 2-alkyl-and 2-benzyloxymethyl-3-phospholene 1-oxides, which were subjected to osmium (VIII) oxide-catalyzed diastereoselective cis-dihydroxylation to give new C-glycoside derivatives of Furanose-type phosphono sugars, with twist conformation.
Reformatsky Type Reaction Promoted by Hexabutyldistannane
Authors: Shibata Ikuya , Yamaguchi Takashi , Baba Akio , Matsuda Haruo
Published: March 2006

Bu3SnSnBu3 proved to be effective reagent for Reformatsky reaction. The use of Bu2SnI2 as an additive was essential, which proved to be effective for generation of organotin (IV) enolates. From the reaction with aldehydes, aldol type products were obtained in good yields.
Characterization of the Cleavage of β-Glucosidic Linkage by Trichoderma viride Cellulase Using Regioselectively Substituted Methylcelluloses
Authors: Kondo Tetsuo , Nojiri Masanobu
Published: March 2006

Regioselectively substituted methylcelluloses having a uniform structure, 6-O-methylcellulose, was degraded by the cellulase of Trichoderma viride while 2,3-di-O-methylcellulose(2) was not. In contrast, a substrate having a trace amount of unsubstituted units in compound 2 was depolymerized by the cellulase, suggesting that glucosidic bonds between non-substituted and 2,3-di-O-substituted units were selectively cleaved.
The Simple Preparation of Aldehydes and Ketones by the Photo-Oxygen Rearrangement of Naphtho[1,8-de]dithiin Monooxides
Authors: Furukawa Naomichi , Fujii Takayoshi , Kimura Takeshi , Fujihara Hisashi
Published: March 2006

Naphthalene-1,8-dithiol reacted with aldehydes to give dithioacetals which were oxidized to 2-substituted naphtho[1,8-de]1,3-dithiin-1-oxides (4). 2,2-Disubstituted naphtho[1,8-de]1,3-dithiin-1-oxides (5) were obtained on treatment of 4 with NaH/electrophiles. Photolysis of 4 and 5 undergoes intramolecular oxygen rearrangement to generate aldehydes and ketones quantitatively together with naphthalene-1,8-dithiole.
Complementary Diastereoselectivity in the Synthesis and Hydrolysis of Acylated Cyclodextrins
Authors: Coates John H , Easton Christopher J , Fryer Nicholas L , Lincoln Stephen F
Published: March 2006

The diastereoselectivity of acylation of β-cyclodextrin with the acid chlorides of Ibuprofen, Flurbiprofen and 2-phenylpropanoic acid is complementary, in absolute and relative terms, to that observed in the hydrolysis of the corresponding cyclodextrin esters.
Transmembrane Electron Transfer across a Keratin Membrane and Lipid Bilayers Catalyzed by Manganese Porphyrin Dimers
Authors: Iida Kouji , Nango Mamoru , Hikita Masaya , Tajima Takeharu , Kurihara Takayuki , Yamashita Keiji , Tsuda Kazuichi , Dewa Takehisa , Komiyama Jiro , Nakata Masahiko , Ohtsuka Yoshiki
Published: March 2006

Transmembrane electron transfer across S-cyanoethylated keratin (SCEK) and liposomal membranes catalyzed by (1), MnTTP-(CH2)n-MnP(COOMe)3, n = 2, 3, 12 showed that an enhanced electron transfer was observed especially when n = 2 or 3 on (1) in these membranes and imidazole was present.
Lipase-Catalyzed Kinetic Resolution of trans-2,5-Disubstituted Pyrrolidine Derivatives
Authors: Kawanami Yasuhiro , Moriya Hitoko , Goto Yuka
Published: March 2006

Enantioselective preparation of (−)-(2S,5S)-N-benzyl-trans-2,5-bis(acetoxymethyl)pyrrolidine was carried out by the lipase-catalyzed hydrolysis of racemic diacetate in phosphate buffer contained 20% DMSO.
Glucose Sensor Based on a Solid Electrolyte Cell Using Sodium Ion Conductor
Authors: Lisdat Fred , Yamada Akihiro , Miura Norio , Yamazoe Noboru
Published: March 2006

A glucose sensor was developed based on a solid electrolyte cell as a transducer. The sensor element uses a sodium ion conductor (NASICON) as a solid electrolyte and a Pt-layer with immobilized GOD as a sensing electrode. EMF of the sensor varies logarithmically with glucose concentration from 5 × 10−5 to 5 × 10−3 M, following Nernst’s equation (−53 mV/dec). The sensing mechanism as well as the interface of potential formation were investigated.
Fragmentation of Triple Cubane-Framework in [(Cp*Rh)4Mo4O16] (Cp* = η5-C5Me5) by MeSH into Tetranuclear Parts in [{Cp*Rh(μ-SMe)3MoO}2(μ-O)2] and [{Cp*Rh(μ-SMe)3MoO}2(μ-O)(μ-S)] Providing a Novel System for Studying Stereodynamics of Thiolate Complexes
Authors: Xi Rimo , Wang Bateer , Abe Masaaki , Ozawa Yoshiki , Isobe Kiyoshi
Published: March 2006

Reaction of the triple cubane-type cluster [(Cp*Rh)4Mo4O16] with MeSH gave two tetranuclear complexes of [{Cp*Rh(μ-SMe)3MoO}2(μ-O)2] and [{Cp*Rh(μ-SMe)3MoO}2(μ-O)(μ-S)] which were characterized by X-ray structural analysis. The stereodynamics of the two complexes was studied by variable-temperature 1H and 17O NMR as well as 13C NMR spectroscopy.
Preparation of Fine-particle Platinum-ruthenium Composite Catalyst Highly-active for Liquid-phase Alkane Dehydrogenation
Authors: Hama Shunichi , Saito Yasukazu
Published: March 2006

A Pt-Ru metal composite catalyst prepared from complexes with different charges, [Pt3(CO)6]52− and [(C6Me6)2Ru]2+, exhibited monodispersed distribution with respect to particle size and composition. A synergetic effect on ethylcyclohexane dehydrogeno-aromatization was well demonstrated under boiling and refluxing conditions, contrary to the case prepared from [Pt3(CO)6]52− and neutral Ru3(CO)12.
Crystallographic Changes of C60 Film Induced by Electrochemical Doping of Tetra-n-butylammonium Ions
Authors: Tomura Keiji , Nishizawa Matsuhiko , Takemura Daigo , Matsue Tomokazu , Uchida Isamu
Published: March 2006

Crystallographic changes of C60 thin film during electrochemical reduction and reoxidation in acetonitrile containing of tetra-n-butylammonium (TBA+) were studied by X-ray diffraction (XRD) and scanning electron microscope (SEM). XRD spectra showed a reversible structure change due to the electrochemical doping of TBA+.
Isomerization Behavior of Halostilbene Radical Cations in the Excited States. Two-Color Photochemistry of Stilbene Derivatives
Authors: Kuriyama Yasunao , Hashimoto Fumiko , Tsuchiya Masahiro , Sakuragi Hirochika , Tokumaru Katsumi
Published: March 2006

Two-color laser excitation of (Z)-4,4′-dichlorostilbene and (Z)-4,4′-difluorostilbene with 425- and 500-nm laser pulses in acetonitrile containing 9,10-dicyanoanthracene and biphenyl exhibited a spectral change indicating a rapid conversion of the Z-radical cations in the excited state to the corresponding E-radical cations in a one-way fashion. The efficiencies of isomerization were determined and the isomerization energy surfaces were discussed.
Reaction of 2-(Ethoxycarbonyl)pentadienylsilane under Ritter Condition. Formation of α-Methylene-γ-lactone by Self-cyclization
Authors: Kuroda Chiaki , Mitsumata Naoko
Published: March 2006

An acylative C(3)-C(4)-bond cleavage of 4,5-disubstituted-2-trimethylsilylmethylpenta-2,4-dienoate occurred by treatment with trifluoromethanesulfonic acid in nitriles, while a self-cyclization giving an α-methylene-γ-lactone also occurred when the reactions were carried out in bulky nitriles.