bluuebunny/crossref_metadata_2025 huggingface dataset:
Solar Burn Reactivation Induced by Methotrexate
Authors: DeVore Kelli J.
Published: March 2010

Solar burn reactivation, a rare and idiosyncratic drug reaction, has been reported with the use of a variety of drugs. This reaction is believed to be the result of exposure to ultraviolet light during the subsiding phase of an acute inflammatory reaction. It affects areas of the body that have been previously sunburned. We describe a 16–year‐old girl who was receiving treatment for acute lymphoblastic leukemia and experienced a second‐degree solar burn reactivation reaction to methotrexate. The patient had a mild sunburn on her face and shoulders the day she went to the oncology clinic for her interim maintenance chemotherapy with vincristine 1.5 mg/m2/dose and methotrexate 100 mg/m2/dose. Three days later, she returned to the clinic with a 2–day history of fever (≤ 100.2°F), nausea, vomiting, and malaise; the sunburn on her face and shoulders also had become severe, without further sun exposure. Laboratory results revealed elevated blood urea nitrogen and serum creatinine concentrations, and her methotrexate level was elevated at 0.9 mM. The patient was diagnosed with acute renal failure, dehydration, methotrexate toxicity, and second‐degree solar burn reactivation reaction. She was admitted to the children's hospital and treated with sodium bicarbonate, acetaminophen with codeine, ondansetron, and silvadene cream. On hospital day 3, the patient's methotrexate level decreased to less than 0.1 mM. The sunburn continued to heal, and after a 14–day hospital stay, complicated by a streptococcal infection, grade 3 mucositis, bacteremia, and mild gastritis and duodenitis, the patient recovered and was discharged. Use of the Naranjo adverse drug reaction probability scale indicated a probable relationship (score of 6) between the patient's solar burn reactivation and methotrexate. Although methotrexate‐induced solar burn reactivation is rare, clinicians should be aware of this potential adverse reaction and consider delaying administration of methotrexate by 5–7 days if a patient reports ultraviolet‐related erythema in the past 2–4 days or presents with a notable sunburn.
Heparin Management in a Patient with Thyroid Storm
Authors: Belchikov Yuly G. , Marotta Sandra E.
Published: March 2010

Management of atrial fibrillation during thyroid storm includes anticoagulation for risk of clot propagation. Physiologic changes that occur in patients with thyroid storm may lead to heparin resistance and inappropriate anticoagulation. Factors contributing to heparin resistance include antithrombin deficiency, increased heparin clearance, and increased levels of factor VIII. We describe a 30–year‐old woman who was hospitalized with thyroid storm. She subsequently developed atrial fibrillation, and unfractionated heparin was started. Over the next 4 days, the heparin infusion rate was titrated to an exaggerated dose of 2100 units/hour (33 units/kg/hr) in order to attain a therapeutic response. By hospital day 7, her atrial fibrillation had resolved; the heparin infusion was discontinued, and the patient remained clinically stable with no sequelae. The exact mechanism of heparin resistance in thyroid storm is unknown; however, data have shown a positive correlation between factor VIII and thyroxine levels. This patient had an elevated thyroxine level of 32.5 μg/dl, which suggested that an increased factor VIII level was the probable mechanism of heparin resistance. Recognition of possible heparin resistance in patients with thyroid storm will allow clinicians to promptly identify appropriate interventions to ensure adequate anticoagulation in this high‐risk patient population. Key Words: hyperthyroidism, thyroid storm, unfractionated heparin, UFH, heparin resistance, activated partial thromboplastin time.
Acute Psychosis Associated with Dissociated Sleep‐Wakefulness State After Mirtazapine Treatment
Authors: Felthous Alan R. , Wenger Philip J. , Hoevet Rod
Published: March 2010

Tricyclic antidepressants decrease rapid eye movement (REM) sleep and may suppress sleep atonia. Reports indicate that these agents can induce visual hallucinations, sometimes characterized as hypnopompic or associated with a dissociated sleep‐wakefulness state. In addition, disturbing dreams and confusional states were reported during clinical trials and in subsequent studies. To our knowledge, only two cases of nightmares associated with mirtazapine, a tetracyclic antidepressant, have been previously reported. We describe a 43–year‐old Caucasian man with major depressive disorder who started mirtazapine 15 mg at bedtime because he had poor symptom control with other antidepressant drugs. Three days later, vivid dream activity was noted, evolving into realistic nightmares that the patient was not able to distinguish from reality on awakening. Acute paranoia was suspected, and haloperidol was started. The dream activity then ended, and within 3 days the patient was able to identify the dreams as unreality. Haloperidol was discontinued, but mirtazapine was continued, and the vivid dream activity persisted; however, reality testing when awake was intact. A short course of haloperidol restored the patient's reality testing, and mirtazapine was eventually replaced with bupropion. The unusual nocturnal activity resolved as a result. Clinicians should be aware of the possible transition from exceptionally vivid dreams to REM sleep behavior disorder and psychosis based on dream content as an adverse effect of mirtazapine.
FDA Approval Summary: Temsirolimus as Treatment for Advanced Renal Cell Carcinoma
Authors: Kwitkowski Virginia E. , Prowell Tatiana M. , Ibrahim Amna , Farrell Ann T. , Justice Robert , Mitchell Shan Sun , Sridhara Rajeshwari , Pazdur Richard
Published: March 2010

Learning Objectives

After completing this course, the reader will be able to: Compare temsirolimus with IFN-α for the treatment of adults with treatment-naïve, advanced, poor-prognosis RCC and discuss the differences in OS time and PFS time for each.Enumerate the laboratory parameters that should be monitored at baseline and while patients are receiving temsirolimus and implement appropriate laboratory monitoring procedures.

This article is available for continuing medical education credit at CME.TheOncologist.com

This report summarizes the U.S. Food and Drug Administration (FDA)'s approval of temsirolimus (Torisel®), on May 30, 2007, for the treatment of advanced renal cell carcinoma (RCC). Information provided includes regulatory history, study design, study results, and literature review.

A multicenter, three-arm, randomized, open-label study was conducted in previously untreated patients with poor-prognosis, advanced RCC. The study objectives were to compare overall survival (OS), progression-free survival (PFS), objective response rate, and safety in patients receiving interferon (IFN)-α versus those receiving temsirolimus alone or in combination with IFN-α.

In the second planned interim analysis of the intent-to-treat population (n = 626), there was a statistically significant longer OS time in the temsirolimus (25 mg) arm than in the IFN-α arm (median, 10.9 months versus 7.3 months; hazard ratio [HR], 0.73; p = .0078). The combination of temsirolimus (15 mg) and IFN-α did not lead to a significant difference in OS compared with IFN-α alone. There was also a statistically significant longer PFS time for the temsirolimus (25 mg) arm than for the IFN-α arm (median, 5.5 months versus 3.1 months; HR, 0.66, p = .0001).

Common adverse reactions reported in patients receiving temsirolimus were rash, asthenia, and mucositis. Common laboratory abnormalities were anemia, hyperglycemia, hyperlipidemia, and hypertriglyceridemia. Serious but rare cases of interstitial lung disease, bowel perforation, and acute renal failure were observed.

Temsirolimus has demonstrated superiority in terms of OS and PFS over IFN-α and provides an additional treatment option for patients with advanced RCC.
Caspase Inhibitor Therapy Synergizes With Costimulation Blockade to Promote Indefinite Islet Allograft Survival
Authors: Emamaullee Juliet A. , Davis Joy , Pawlick Rena , Toso Christian , Merani Shaheed , Cai Sui-Xiong , Tseng Ben , Shapiro A.M. James
Published: March 2010

OBJECTIVE

Costimulation blockade has emerged as a selective nontoxic maintenance therapy in transplantation. However, these drugs must be combined with other immunomodulatory agents to ensure long-term graft survival.

RESEARCH DESIGN AND METHODS

Recent work has demonstrated that caspase inhibitor therapy (EP1013) prevents engraftment phase islet loss and markedly reduces the islet mass required to reverse diabetes. The “danger” hypothesis suggests that reduction in graft apoptosis should reduce the threshold for immunosuppression and increase the possibility for tolerance induction. Thus, the impact of combination of EP1013 treatment with costimulation blockade (CTLA4-Ig) was investigated in this study.

RESULTS

Islet allografts were completed in fully major histocompatibility complex (MHC)-mismatched mice (Balb/C to B6). When animals received vehicle or EP1013, there was no difference in graft survival. CTLA4-Ig resulted in prolonged graft survival in 40% of the animals, whereas EP1013+CLTA4-Ig resulted in a significant increase in graft survival (91% >180 days; P = 0.01). Ex vivo analysis revealed that animals receiving EP1013 or EP1013+CTLA4-Ig had a reduced frequency of alloreactive interferon (IFN)-γ–secreting T-cells and an increased frequency of intragraft Foxp3+ Treg cells. Alloantibody assays indicated that treatment with EP1013 or CTLA4-Ig prevented allosensitization.

CONCLUSIONS

This study suggests that addition of caspase inhibitor therapy to costimulation blockade will improve clinical transplantation by minimizing immune stimulation and thus reduce the requirement for long-term immunosuppressive therapy. The approach also prevents allosensitization, which may be an important component of chronic graft loss in clinical transplantation.
Effects of Exenatide and Lifestyle Modification on Body Weight and Glucose Tolerance in Obese Subjects With and Without Pre-Diabetes
Authors: Rosenstock Julio , Klaff Leslie J. , Schwartz Sherwyn , Northrup Justin , Holcombe John H. , Wilhelm Kenneth , Trautmann Michael
Published: March 2010

OBJECTIVE

To assess the effects of exenatide on body weight and glucose tolerance in nondiabetic obese subjects with normal or impaired glucose tolerance (IGT) or impaired fasting glucose (IFG).

RESEARCH DESIGN AND METHODS

Obese subjects (n = 152; age 46 ± 12 years, female 82%, weight 108.6 ± 23.0 kg, BMI 39.6 ± 7.0 kg/m2, IGT or IFG 25%) were randomized to receive exenatide (n = 73) or placebo (n = 79), along with lifestyle intervention, for 24 weeks.

RESULTS

Exenatide-treated subjects lost 5.1 ± 0.5 kg from baseline versus 1.6 ± 0.5 kg with placebo (exenatide − placebo, P < 0.001). Placebo-subtracted difference in percent weight reduction was −3.3 ± 0.5% (P < 0.001). Both groups reduced their daily calorie intake (exenatide, −449 cal; placebo, −387 cal). IGT or IFG normalized at end point in 77 and 56% of exenatide and placebo subjects, respectively.

CONCLUSIONS

Exenatide plus lifestyle modification decreased caloric intake and resulted in weight loss in nondiabetic obesity with improved glucose tolerance in subjects with IGT and IFG.
Randomized Clinical Trial of Quick-Release Bromocriptine Among Patients With Type 2 Diabetes on Overall Safety and Cardiovascular Outcomes
Authors: Gaziano J. Michael , Cincotta Anthony H. , O'Connor Christopher M. , Ezrokhi Michael , Rutty Dean , Ma Z.J. , Scranton Richard E.
Published: March 2010

OBJECTIVE

Quick-release bromocriptine (bromocriptine-QR), a D2 dopamine receptor agonist, is indicated as a treatment for type 2 diabetes. The Cycloset Safety Trial, a 52-week, randomized, double-blind, multicenter trial, evaluated the overall safety and cardiovascular safety of this novel therapy for type 2 diabetes.

RESEARCH DESIGN AND METHODS

A total of 3,095 patients with type 2 diabetes were randomized 2:1 to bromocriptine-QR or placebo in conjunction with the patient's usual diabetes therapy (diet controlled only or up to two antidiabetes medications, including insulin). The all-cause–safety end point was the occurrence of any serious adverse event (SAE), with a hazard ratio (HR) noninferiority margin of 1.5. In a prespecified analysis, the frequency of cardiovascular disease (CVD) events defined as a composite of myocardial infarction, stroke, coronary revascularization, and hospitalization for angina or congestive heart failure was evaluated using modified intent-to-treat analysis (clinicaltrials.gov, NCT00377676).

RESULTS

In the bromocriptine-QR group, 176 (8.6%) people reported SAEs compared with 98 (9.6%) in the placebo group (HR 1.02 [96% one-sided CI 1.27]). Fewer people reported a CVD end point in the bromocriptine-QR group versus the placebo group (37 [1.8%] vs. 32 [3.2%], respecively) (HR 0.60 [95% two-sided CI 0.35–0.96]). Nausea was the most commonly reported adverse event in the bromocriptine-QR group.

CONCLUSIONS

The frequency of SAEs was comparable between the treatment arms. Compared with patients in the placebo arm, fewer patients taking bromocriptine-QR experienced a cardiovascular end point.
The Cost-Effectiveness of Continuous Glucose Monitoring in Type 1 Diabetes
Authors: Huang Elbert S. , O'Grady Michael , Basu Anirban , Winn Aaron , John Priya , Lee Joyce , Meltzer David , Kollman Craig , Laffel Lori , Tamborlane William , Weinzimer Stuart , Wysocki Tim ,   the Juvenile Diabetes Research Foundation Continuous Glucose Monitoring Study Group
Published: March 2010

OBJECTIVE

Continuous glucose monitoring (CGM) has been found to improve glucose control in type 1 diabetic patients. We estimated the cost-effectiveness of CGM versus standard glucose monitoring in type 1 diabetes.

RESEARCH DESIGN AND METHODS

This societal cost-effectiveness analysis (CEA) was conducted in trial populations in which CGM has produced a significant glycemic benefit (A1C ≥7.0% in a cohort of adults aged ≥25 years and A1C <7.0% in a cohort of all ages). Trial data were integrated into a simulation model of type 1 diabetes complications. The main outcome was the cost per quality-adjusted life-year (QALY) gained.

RESULTS

During the trials, CGM patients experienced an immediate quality-of-life benefit (A1C ≥7.0% cohort: 0.70 quality-adjusted life-weeks [QALWs], P = 0.49; A1C <7.0% cohort: 1.39 QALWs, P = 0.04) and improved glucose control. In the long-term, CEA for the A1C ≥7.0% cohort, CGM was projected to reduce the lifetime probability of microvascular complications; the average gain in QALYs was 0.60. The incremental cost-effectiveness ratio (ICER) was $98,679/QALY (95% CI −60,000 [fourth quadrant] to −87,000 [second quadrant]). For the A1C <7.0% cohort, the average gain in QALYs was 1.11. The ICER was $78,943/QALY (15,000 [first quadrant] to −291,000 [second quadrant]). If the benefit of CGM had been limited to the long-term effects of improved glucose control, the ICER would exceed $700,000/QALY. If test strip use had been two per day with CGM long term the ICER for CGM would improve significantly.

CONCLUSIONS

Long-term projections indicate that CGM is cost-effective among type 1 diabetic patients at the $100,000/QALY threshold, although considerable uncertainty surrounds these estimates.
Renal Hyperfiltration Is a Determinant of Endothelial Function Responses to Cyclooxygenase 2 Inhibition in Type 1 Diabetes
Authors: Cherney David Z.I. , Miller Judith A. , Scholey James W. , Nasrallah Rania , Hébert Richard L. , Dekker Maria G. , Slorach Cameron , Sochett Etienne B. , Bradley Timothy J.
Published: March 2010

OBJECTIVE

Our aim was to examine the effect of cyclooxygenase 2 (COX2) inhibition on endothelial function in subjects with type 1 diabetes analyzed on the basis of renal filtration status.

RESEARCH DESIGN AND METHODS

Flow-mediated dilation (FMD) was determined in type 1 diabetic subjects and hyperfiltration (glomerular filtration rate ≥135 ml/min/1.73 m2, n = 13) or normofiltration (glomerular filtration rate ≥135 ml/min/1.73 m2, n = 11). Studies were performed before and after celecoxib (200 mg daily for 14 days) during euglycemia and hyperglycemia.

RESULTS

Baseline parameters were similar in the two groups. Pretreatment, FMD was augmented in normofiltering versus hyperfiltering subjects during clamped euglycemia (10.2 ± 5.3% vs. 5.9 ± 2.3%, P = 0.003). COX2 inhibition suppressed FMD in normofiltering (10.2 ± 5.3% to 5.8 ± 3.4%, P = 0.006) versus hyperfiltering subjects (ANOVA interaction, P = 0.003).

CONCLUSIONS

Systemic hemodynamic function, including the response to COX2 inhibition, is related to filtration status in diabetic subjects and may reflect general endothelial dysfunction.
High-Normal Serum Uric Acid Increases Risk of Early Progressive Renal Function Loss in Type 1 Diabetes
Authors: Ficociello Linda H. , Rosolowsky Elizabeth T. , Niewczas Monika A. , Maselli Nicholas J. , Weinberg Janice M. , Aschengrau Ann , Eckfeldt John H. , Stanton Robert C. , Galecki Andrzej T. , Doria Alessandro , Warram James H. , Krolewski Andrzej S.
Published: March 2010

OBJECTIVE

We previously described a cross-sectional association between serum uric acid and reduced glomerular filtration rate (GFR) in nonproteinuric patients with type 1 diabetes. Here, we prospectively investigated whether baseline uric acid impacts the risk of early progressive renal function loss (early GFR loss) in these patients.

RESEARCH DESIGN AND METHODS

Patients with elevated urinary albumin excretion (n = 355) were followed for 4–6 years for changes in urinary albumin excretion and GFR. The changes were estimated by multiple determinations of albumin-to-creatinine ratios (ACRs) and serum cystatin C (GFRcystatin).

RESULTS

At baseline, the medians (25th–75th percentiles) for uric acid, ACR, and GFRcystatin values were 4.6 mg/dl (3.8–5.4), 26.2 mg/g (15.1–56.0), and 129 ml/min per 1.73 m2 (111–145), respectively. During the 6-year follow-up, significant association (P < 0.0002) was observed between serum uric acid and development of early GFR loss, defined as GFRcystatin decline exceeding 3.3% per year. In baseline uric acid concentration categories (in mg/dl: <3.0, 3.0–3.9, 4.0–4.9, 5.0–5.9, and ≥6), the risk of early GFR loss increased linearly (9, 13, 20, 29, and 36%, respectively). This linear increase corresponds to odds ratio 1.4 (95% CI 1.1–1.8) per 1 mg/dl increase of uric acid. The progression and regression of urinary albumin excretion were not associated with uric acid.

CONCLUSIONS

We found a clear dose-response relation between serum uric acid and risk of early GFR loss in patients with type 1 diabetes. Clinical trials are warranted to determine whether uric acid–lowering drugs can halt renal function decline before it becomes clinically significant.
Juvenile Polyposis of Infancy Associated with Paracentric Inversion and Deletion of Chromosome 10 in a Hispanic Patient: A Case Report
Authors: Vargas-González Roberto , de la Torre-Mondragón Luis , Aparicio-Rodríguez Juan Manuel , Paniagua-Morgan Froylan , López-Hernández Gerardo , Garrido-Hernández Miguel Angel , Nuñez-Barrera Sandra
Published: March 2010

Juvenile polyposis of infancy is a rare genetic disorder, involving multiple hamartomatous polyps of the gastrointestinal tract, which usually has a very aggressive clinical course and is often fatal. It is characterized by early onset (during the 1st months of life) and by diffuse juvenile polyposis with anemia, recurrent gastrointestinal bleeding, diarrhea, rectal prolapse, intussusception, protein-losing enteropathy, starvation, and malnutrition. There is a hypothesis that mutation of the tumor-suppressor genes BMPR1A and PTEN, located on the long arm of chromosome 10, is associated with the development of this disease. Medical treatment for this disorder is challenging and should be conservative whenever possible. We present the case of a 3-year-old girl with juvenile polyposis of infancy who eventually died from mesenteric artery thrombosis during surgical colectomy. Karyotype of the patient showed a paracentric inversion in 10q and a deletion in 10p. We will briefly comment on some genetic considerations of this disease.
Global mapping of ZBTB7A transcription factor binding sites in HepG2 cells
Authors: Zu Xuyu , Yu Lingling , Sun Yiming , Tian Jing , Liu Feng , Sun Qinsheng , He Shengnan , Sun Guang , Luo Weishi , Jiang Yuyang
Published: March 2010

ZBTB7A is a known proto-oncogene that is implicated in carcinogenesis and cell differentiation and development. Fully understanding the function of ZBTB7A in cellular processes could provide useful strategies for cancer treatment and development-associated disease therapy. Here, global mapping of ZBTB7A transcription factor binding sites was developed by utilizing microarray technology in HepG2 cells. The data obtained from the microarrays was further validated via chromatin immunoprecipitation-PCR (ChIP-PCR) and real time-PCR, and it was revealed that ZBTB7A may be one of the regulators of neural development. ZBTB7A target signal pathways were identified in signal pathway and GO (Gene Ontology) analyses. This is the first report on the global mapping of ZBTB7A downstream direct targets, and these findings will be useful in understanding the roles of ZBTB7A in cellular processes.
The anti-apoptotic protein lifeguard is expressed in breast cancer cells and tissues
Authors: Bucan Vesna , Reimers Kerstin , Choi Claudia , Eddy Mau-Thek , Vogt Peter
Published: March 2010

Lifeguard (LFG) is an anti-apoptotic protein that inhibits Fas-mediated death in tumour cells. However, the molecular function of human LFG in the carcinogenesis of human breast cells is uncertain. We studied the expression and function of endogenous LFG in four breast cancer cell lines (MCF-7, MDA-MB-231, T-47D and HS 578T), a human breast epithelial cell line (HS 578Bst), and in healthy and cancerous breast tissues. Molecular (Western blot and RT-PCR) and immunohistochemical techniques were used to investigate the LFG expression. To investigate the breast cancer cell proliferation in the presence of Fas, we performed fluorescent cell viability assays. The possible association of Fas with LFG was analyzed by immunofluorescence microscopy. In this paper, we provide convincing evidence that LFG is overexpressed in several human breast cancer cell lines. More importantly, we found that the LFG expression correlates with high tumour grades in primary breast tumours. Finally, we demonstrated that Fas sensitivity is reduced in breast cancer cell lines expressing LFG. Our results indicated that LFG is strongly expressed in breast cancer epithelial cells. Moreover, the overexpression of LFG correlated with tumour grade and reduced Fas sensitivity. Our findings support the idea that LFG may have a role in the downregulation of apoptosis in breast cancer cells.
The INQUA Loess Commission as a Central European Enterprise
Authors: Smalley Ian , Markovic Slobodan , O’Hara-Dhand Ken
Published: March 2010

The International Union of Quaternary Research (INQUA) organized the study and consideration of the Quaternary Period (the last 2.6 million years in Earth’s history) via a set of commissions, sub-commissions, working groups, projects and programmes. One of the most successful and best records was the Loess Commission (LC) which functioned assub-commission and then commission from 1961 to 2003, resulting in 40 years of useful activity. The history of the LC can be divided into three phases: 1, from 1961–1977 when the President was Julius Fink; 2, from 1977–1991, with President Marton Pecsi; 3, from 1991–2003 with Presidents An Zhi-Sheng and Ian Smalley.

Fink, from Vienna, and Pecsi, from Budapest, gave the LC a distinctly Central European aspect. The nature of loess in Central Europe influenced the nature of the LC but the settings for phases 1 and 2 were quite distinct. Phase 1 was a small scale academic operation, carried out in German. As phase 2 began in 1977 the scope expanded and Central Europe became a base for worldwide loess studies. where the LC language changed to English. Phase 2 was run from a National Geographical Institute and demonstrated a different approach to loess research, although the basic programmes of continent-wide mapping and stratigraphy remained the same. The Commission benefited from this change of style and emphasis. In phase 3 the administration moved away from Central Europe but the Finkian ethos remained solid.
New approaches to European loess: a stratigraphic and methodical review of the past decade
Authors: Zoeller Ludwig
Published: March 2010

This review paper intends to summarize the state of the art in loess research at the first international “Loess-fest’99” conference and to outline progress in loess research during the past decade. The focus is on loess as a terrestrial archive of climatic and environmental change during the Quaternary. The review highlights remarkable new results from regional investigations into European loess, as well as the emergence of new methods and refinements of established techniques, focussing on stratigraphy, dating and palaeoenvironment. It is concluded that loess research during the past decade not only has developed rapidly to take an outstanding place in Quaternary sciences, but also promises exciting perspectives for the next decade, in particular when combined approaches are applied to benefit from the now comprehensive pool of established and new methods.
Loess and dust on Earth and Mars: particle generation by impact mechanisms
Authors: O’Hara-Dhand Ken , Taylor Richard , Smalley Ian , Krinsley David , Vita-Finzi Claudio
Published: March 2010

Impact between windblown quartz grains as a source of desert dust is consistent with laboratory abrasion experiments and has received some field confirmation in the Negev. The suggestion is that an important process on Mars now gains support from laboratory studies; even though their geochemical interpretation is controversial, they show that dust generation by impact is tenable even for quartz.

A simple mechanism for small dust production from sand seas is proposed; internal stresses can be mobilized by impact energy. A speculative mechanism (the andesite scenario) is proposed for fine particle production by particle impact on Mars. The internal stress range in terrestrial sand grains may vary, depending on the nature of the source rock, and this may influence particle production by impact processes.
Luminescence of aqueous reactions derived NiWO4 powders and sol-gel deposited films
Authors: He Haiyan
Published: March 2010

NiWO4 powders have been synthesized by reaction between NiCl2 and Na2WO4 aqueous solutions and following calcinations at different temperatures. X-ray diffraction and scanning electron microscopy analysis were used to characterize the powders. Single phase NiWO4 powders were formed above a calcining temperature of 600 °C. X-ray diffraction analysis indicated that the NiWO4 powders had a monoclinic structure and particle size of 26.8 nm and 30.3 nm for calcining temperatures of 600 °C and 700 °C, respectively. A little increase in intensity of the X-ray diffraction peaks was observed when increasing the calcining temperature from 600 °C to 700 °C. Scanning electron microscopy indicated that powders had uniform and very small particle size. The powders showed a broad blue-green emission band. The broad band of NiWO4 powders calcined at 600 °C consisted of 423.2 nm (2.93 eV), 487.3 nm (2.54 eV) and two weak bands at 447.0 nm (2.77 eV), and 532.0 nm (2.33 eV). Small shifts in the peaks of excitation and luminescence and small increases in intensities were observed when increasing calcining temperature to 700 °C. The films were deposited using the sol-gel method and using the precipitate as starting materials. The deposited films showed a similar blue-green emission to that of the powders.
High temperature stability of Cr-carbides in an experimental Co–Re-based alloy
Authors: Mukherji Debashis , Klauke Michael , Strunz Pavel , Zizak Ivo , Schumacher Gerhard , Wiedenmann Albrecht , Rösler Joachim
Published: March 2010

The stability of the microstructure at high temperatures was studied in an experimental Co–Re-based alloy. The experimental alloy is mainly strengthened by Cr-carbides, particularly by those in the form of thin lamellar plates. Electron microscopic investigation on samples exposed for up to 1 000 h to temperatures of 1 000 and 1 200 °C showed that Cr23C6 type carbides present in the alloy in different morphologies are unstable at these temperatures. It was also observed that the alloy hardness dropped after exposing the samples to elevated temperatures and much of this loss occurred within the first 100 h. In-situ diffraction measurements with synchrotron radiation showed that carbide dissolution started as early as 3 h of holding at 1 000 °C. Moreover, in-situ small angle neutron scattering results indicated that the carbides at the grain boundaries and the blocky carbides dissolve first and then the thin lamellar carbides. Further, the enrichment of Cr in the Co-matrix phase, which took place due to the dissolution of Cr-carbides, stabilized a Cr–Re-rich σ phase. Although the dissolution of lamellar carbides results in a significant loss of strength, the formation of σ phase with extremely high hardness partly compensated the for loss. The σ phase is stable even at 1 200 °C.
Phase transformation temperatures of pure iron and low alloyed steels in the low temperature region using DTA
Authors: Smetana Bedrřich , Zlá Simona , Dobrovská Jana , Kozelský Petr
Published: March 2010

The paper reports a study of temperatures of phase transitions of nine samples of real grades of low-alloyed steels, including one sample of pure iron, using differential thermal analysis. Temperatures of phase transitions were measured in the low-temperature interval (20 – 1 000 °C). Investigated systems were analysed at selected rates of heating/cooling and then temperatures of phase transitions for zero heating/cooling rate were determined. The results obtained are compared with temperatures of the equilibrium metastable diagram Fe – C, with results from the software IDS and with temperatures of phase transitions calculated according to relations published in available literature. It follows from the results that differences, sometimes considerable ones, still exist between experimental and theoretical data, which implies the necessity for further systematic research in this area.
Effect of ECAE conditions on the microstructure, texture and mechanical properties of an extruded Mg–Zn–Y–Zr alloy
Authors: Tang W. N. , Chen R. S. , Zhou J. , Han E. H.
Published: March 2010

Equal channel angular extrusion (ECAE) experiments of an extruded Mg–Zn–Y–Zr alloy with an intense basal texture were performed up to 8 passes at 250 and 350 °C through route Bc (billets with a rotation of 90° in the same direction between passes) and route A (without rotation between passes). It was found that under these ECAE conditions significant grain refinement was achieved. The initial texture of the alloy gradually altered as the number of ECAE passes increased. The ductility of the alloy was improved in all the cases after eight passes. The yield strength of the alloy ECAEed through route Bc considerably decreased with the passes increasing, as a result of the formation of the texture component with the basal planes inclined at about 45° to the ECAE direction. The yield strength of the material ECAEed at 250 °C with a finer grain structure was considerably lower than that at 350 °C with a coarser grain structure. This abnormal phenomenon was attributed to more crystals in the former being oriented to be more favorable for basal slip.
The study of recrystallisation and crystallographic texture genesis in industrial steels
Authors: Réglé Hélène
Published: March 2010

Charles Crussard actively participated in the foundation of the IRSID laboratory in 1948. He integrated this institute in 1952 as chief of the Physical Metallurgy Department and among the scientific fields that he initiated were the plasticity and the recrystallisation of steels. Nowadays, these are still active research fields at the ArcelorMittal Research laboratory (formerly called IRSID) and the purpose of this paper is to illustrate the heritage of the research subjects that Crussard initiated and how his vision has influenced our work at IRSID.
High-speed milling strategies in mould manufacturing
Authors: Aksoy Ziya , Gür Yílmaz , Eren İlker
Published: March 2010

High-speed cutting is one of the key issues in mould manufacturing. But to apply high-speed milling to mould manufacturing, unlike conventional milling, it is necessary to define specific cutting parameters. This article aims to define the influence of milling strategies and cutting parameters, such as cutting speed, feeding speed, cutting tool tilting angle, on the process stability.

Long tool life and cutting strategy have a major influence on the results of machining hardened steel. Machining with drawing cut and down-cutting in copper and with drawing cut and up-cutting in hardened steel gave the best results with respect to tool wear and surface quality. Tool approach across the feeding direction results in heavy impact loads on the tool which lead to heavy tool wear and substantial dimensional deviations.

Good surface quality is achieved in machining of a work piece of 2 363 steel (X100CrMoV51) hardened to 60 HRC, using the strategy of up-cutting with drawing cut and a tool approach with a tilting angle of 15 degrees. While up-cutting allows for achieving better surface quality, down-cutting provides longer tool life than up-cutting for all angles of approach.
Graph Extremities Defined by Search Algorithms
Authors: Berry Anne , Blair Jean R.S. , Bordat Jean-Paul , Simonet Geneviève
Published: March 2010

Graph search algorithms have exploited graph extremities, such as the leaves of a tree and the simplicial vertices of a chordal graph. Recently, several well-known graph search algorithms have been collectively expressed as two generic algorithms called MLS and MLSM. In this paper, we investigate the properties of the vertex that is numbered 1 by MLS on a chordal graph and by MLSM on an arbitrary graph. We explain how this vertex is an extremity of the graph. Moreover, we show the remarkable property that the minimal separators included in the neighborhood of this vertex are totally ordered by inclusion.
Study on QSTR of Benzoic Acid Compounds with MCI
Authors: Li Zuojing , Sun Yezhi , Yan Xinli , Meng Fanhao
Published: March 2010

Quantitative structure-toxicity relationship (QSTR) plays an important role in toxicity prediction. With the modified method, the quantum chemistry parameters of 57 benzoic acid compounds were calculated with modified molecular connectivity index (MCI) using Visual Basic Program Software, and the QSTR of benzoic acid compounds in mice via oral LD50 (acute toxicity) was studied. A model was built to more accurately predict the toxicity of benzoic acid compounds in mice via oral LD50: 39 benzoic acid compounds were used as a training dataset for building the regression model and 18 others as a forecasting dataset to test the prediction ability of the model using SAS 9.0 Program Software. The model is LogLD50 = 1.2399 × 0JA +2.6911 × 1JA – 0.4445 × JB (R2 = 0.9860), where 0JA is zero order connectivity index, 1JA is the first order connectivity index and JB = 0JA × 1JA is the cross factor. The model was shown to have a good forecasting ability.
Whole Cell Imprinting in Sol-Gel Thin Films for Bacterial Recognition in Liquids: Macromolecular Fingerprinting
Authors: Cohen Tally , Starosvetsky Jeanna , Cheruti Uta , Armon Robert
Published: March 2010

Thin films of organically modified silica (ORMOSILS) produced by a sol-gel method were imprinted with whole cells of a variety of microorganisms in order to develop an easy and specific probe to concentrate and specifically identify these microorganisms in liquids (e.g., water). Microorganisms with various morphology and outer surface components were imprinted into thin sol-gel films. Adsorption of target microorganism onto imprinted films was facilitated by these macromolecular fingerprints as revealed by various microscopical examinations (SEM, AFM, HSEM and CLSM). The imprinted films showed high selectivity toward each of test microorganisms with high adsorption affinity making them excellent candidates for rapid detection of microorganisms from liquids.
7-(3-Chlorophenylamino)-1-cyclopropyl-6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylic Acid
Authors: Al-Hiari Yusuf Mohammad , Qandil Amjad M. , Al-Zoubi Rufaida M. , Alzweiri Muhammed H. , Darwish Rula M. , Shattat Ghassan F. , Al-Qirim Tariq M.
Published: March 2010

7-(3-Chlorophenylamino)-1-cyclopropyl-6-fluoro-8-nitro-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid (2) was prepared and fully characterized by NMR, IR, and MS. Compound 2 exhibited good antibacterial activity against gram-positive standard and resistant strains.
Chemical Sensors Based on Molecularly Imprinted Sol-Gel Materials
Authors: Mujahid Adnan , Lieberzeit Peter A. , Dickert Franz L.
Published: March 2010

The sol-gel technique is earning the worldwide attention of researchers in the field of material science, due to its versatility in synthesizing inorganic ceramic materials at mild conditions. High purity, homogeneity, controlled porosity, stable temperature and nanoscale structuring are the most remarkable features offered by this method for generating highly sensitive and selective matrices to incorporate analyte molecules. The crafting of sol-gel sensors through molecular imprinting has put great influence on the development of innovative chemical sensors, which can be seen from the growing number of publications in this field. The review provides a brief overview of sol-gel sensor applications, and discusses the contribution of molecular imprinting in exploring the new world of sensors.
Fabrication Methods and Luminescent Properties of ZnO Materials for Light-Emitting Diodes
Authors: Lee Ching-Ting
Published: March 2010

Zinc oxide (ZnO) is a potential candidate material for optoelectronic applications, especially for blue to ultraviolet light emitting devices, due to its fundamental advantages, such as direct wide band gap of 3.37 eV, large exciton binding energy of 60 meV, and high optical gain of 320 cm−1 at room temperature. Its luminescent properties have been intensively investigated for samples, in the form of bulk, thin film, or nanostructure, prepared by various methods and doped with different impurities. In this paper, we first review briefly the recent progress in this field. Then a comprehensive summary of the research carried out in our laboratory on ZnO preparation and its luminescent properties, will be presented, in which the involved samples include ZnO films and nanorods prepared with different methods and doped with n-type or p-type impurities. The results of ZnO based LEDs will also be discussed.
Activity of the Extracts and Neolignans from Piper regnellii against Methicillin-Resistant Staphylococcus aureus (MRSA)
Authors: Marçal Flaviano João Basilio , Cortez Diógenes Aparício Garcia , Ueda-Nakamura Tânia , Nakamura Celso Vataru , Filho Benedito Prado Dias
Published: March 2010

Piper regnellii (Miq.) C. DC. var. pallescens (C. DC.) Yunck (Piperaceae) is a medicinal plant traditionally used in Brazil to treat infectious diseases. The extracts obtained of the leaves from P. regnellii were investigated for their antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA). The ethyl acetate extract presented a good activity against MRSA, with minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of 16 μg/mL. Based on this finding, the ethyl acetate extract was fractionated by silica gel column chromatography into nine fractions. The hexane fraction was active against MRSA (MIC at 4 μg/mL). Further column chromatography separation of the hexane fraction afforded the pure compound eupomatenoid-5. The structure of the compound was established by spectral data (1H and 13C NMR HSQC, HMBC, gNOE, IR and MS). Eupomatenoid-5 was the only compound active on the bacterium. The antibacterial property of P. regnellii extract provides preliminary scientific validation for the traditional medicinal use of this plant. The active compound eupomatenoid-5 should be further studied in animal models to verify in vivo efficacy and toxicity.
Norcoclaurine Synthase: Mechanism of an Enantioselective Pictet-Spengler Catalyzing Enzyme
Authors: Bonamore Alessandra , Barba Marco , Botta Bruno , Boffi Alberto , Macone Alberto
Published: March 2010

The use of bifunctional catalysts in organic synthesis finds inspiration in the selectivity of enzymatic catalysis which arises from the specific interactions between basic and acidic amino acid residues and the substrate itself in order to stabilize developing charges in the transition state. Many enzymes act as bifunctional catalysts using amino acid residues at the active site as Lewis acids and Lewis bases to modify the substrate as required for the given transformation. They bear a clear advantage over non-biological methods for their ability to tackle problems related to the synthesis of enantiopure compounds as chiral building blocks for drugs and agrochemicals. Moreover, enzymatic synthesis may offer the advantage of a clean and green synthetic process in the absence of organic solvents and metal catalysts. In this work the reaction mechanism of norcoclaurine synthase is described. This enzyme catalyzes the Pictet-Spengler condensation of dopamine with 4-hydroxyphenylacetaldehyde (4-HPAA) to yield the benzylisoquinoline alkaloids central precursor, (S)-norcoclaurine. Kinetic and crystallographic data suggest that the reaction mechanism occurs according to a typical bifunctional catalytic process.
Triterpenes from Stachyurus himalaicus var. himalaicus Hook. f. et Thoms. ex Benth
Authors: Wang Yun-Song , Huang Rong , Li Ning-Zhong , Xu Hong-Yi , Yang Jing-Hua
Published: March 2010

Four triterpenes 1–4, including a new naturally occurring oleanane-type triterpene 1, were isolated by a multi-step chromatography procedure from the leaves and twigs of Stachyurus himalaicus var. himalaicus Hook. f. et Thoms.ex Benth. The structures of the compounds were elucidated by spectroscopic methods, including HRESIMS, 1H- NMR, 13C-NMR, DEPT, HMQC, HMBC and NOESY spectra. All the isolated compounds were evaluated for their in vitro cytotoxic activities against human Hela cell line.
Synthesis and Biological Evaluation of New 5-Fluorouracil-Substituted Ampelopsin Derivatives
Authors: Zhou Wei-Ming , He Rong-Rong , Ye Jian-Tao , Zhang Na , Liu De-Yu
Published: March 2010

This study reports two novel 5-fluorouracil-substituted ampelopsin derivatives. The structures of two new derivatives were characterized by elemental analysis, 1H-NMR, 13C-NMR, IR and MS. Their anticancer activities in vitro against two cancer cell lines, K562 and K562/ADR, were investigated using the MTT assay, and the results showed that the two new compounds were more effective than reference drugs such as ampelopsin and verapamil.
Implications of Inter-Individual Differences in Clopidogrel Metabolism, with Focus on Pharmacogenetics
Authors: Dahl Marja-Liisa , Gunes Arzu
Published: March 2010

Increasing evidence for the role of pharmacogenetics in treatment resistance to the antiplatelet agent clopidogrel has been gained during the last years. Apart from CYP2C19 genetic polymorphisms, nongenetic factors, particularly drug-drug interactions, age and other clinical characteristics influence the interindividual variability in clopidogrel response to varying degrees. The present article reviews the so far accumulated evidence on the role of pharmacogenetic traits influencing CYP-activity as determinants of the antiplatelet response to clopidogrel, and its clinical implications. The genetic variation in CYP2C19 activity seems to influence short- and long-term antithrombotic effects of clopidogrel to a substantial extent. Prediction models for clopidogrel non-responsiveness that include CYP2C19 genotyping together with relevant non-genetic risk factors are needed to be verified for their potential benefit in individualization of antithrombotic therapy.
Assessment of Thermal Transitions by Dynamic Mechanical Analysis (DMA) Using a Novel Disposable Powder Holder
Authors: Abiad Mohamad G. , Campanella Osvaldo H. , Carvajal M. Teresa
Published: March 2010

Foods and pharmaceuticals materials are exposed to various environmental conditions during processing and while in storage; therefore, stability and quality are key attributes of concern. The properties of foods and pharmaceutical materials that define their quality are affected by conditions such as temperature, humidity and time. Glass transition is considered a key material property to understand how these external conditions affect the stability and quality of foods and pharmaceuticals. Thus, investigating the thermo-mechanical properties of these materials as well as characterizing the glass transition temperature have a great interest not only in the food industry, but also extend to the pharmaceutical and polymer industries. The aim of this study was to design and test a new disposable powder holder that allows the use of a dynamic mechanical analysis (DMA) instrument to test and characterize loose powder samples. The disposable aluminum powder holder was designed and constructed to be used in the single cantilever configuration on a TA Instruments RSA III DMA. Three different powder samples – Felodipine, polyethylene-oxide (MW 900 kDa) and HPMC (E4M) – were used for validation. The use of this powder holder allows the detection of different thermal changes of powder samples without compacting and when large sample size is necessary for detection and/or interpretation.
Estimation of Biological Oxygen Demand and Chemical Oxygen Demand for Combined Sewer Systems Using Synchronous Fluorescence Spectra
Authors: Hur Jin , Lee Bo-Mi , Lee Tae-Hwan , Park Dae-Hee
Published: March 2010

Real-time monitoring of water quality for sewer system is required for efficient sewer network design because it provides information on the precise loading of pollutant to wastewater treatment facilities and the impact of loading on receiving water. In this study, synchronous fluorescence spectra and its first derivatives were investigated using a number of wastewater samples collected in sewer systems in urban and non-urban areas, and the optimum fluorescence feature was explored for the estimation of biochemical oxygen demand (BOD) and chemical oxygen demand (COD) concentrations of sewer samples. The temporal variations in BOD and COD showed a regular pattern for urban areas whereas they were relatively irregular for non-urban areas. Irrespective of the sewer pipes and the types of the areas, two distinct peaks were identified from the synchronous fluorescence spectra, which correspond to protein-like fluorescence (PLF) and humic-like fluorescence (HLF), respectively. HLF in sewer samples appears to be associated with fluorescent whitening agents. Five fluorescence characteristics were selected from the synchronous spectra and the first-derivatives. Among the selected fluorescence indices, a peak in the PLF region (i.e., Index I) showed the highest correlation coefficient with both BOD and COD. A multiple regression approach based on suspended solid (SS) and Index I used to compensate for the contribution of SS to BOD and COD revealed an improvement in the estimation capability, showing good correlation coefficients of 0.92 and 0.94 for BOD and COD, respectively.