bluuebunny/crossref_metadata_2025 huggingface dataset:
A Model System of Development Regulated by the Long‐distance Transport of mRNA
Authors: Hannapel David J.
Published: January 2010

BEL1‐like transcription factors are ubiquitous in plants and interact with KNOTTED1‐types to regulate numerous developmental processes. In potato, the RNA of several BEL1‐like transcription factors has been identified in phloem cells. One of these, StBEL5, and its Knox protein partner regulate tuber formation by targeting genes that control growth. RNA detection methods and grafting experiments demonstrated that StBEL5 transcripts move across a graft union to localize in stolon tips, the site of tuber induction. This movement of RNA originates in source leaf veins and petioles and is induced by a short‐day photoperiod, regulated by the untranslated regions, and correlated with enhanced tuber production. Addition of the StBEL5 untranslated regions to another BEL1‐like mRNA resulted in its preferential transport to stolon tips leading to increased tuber production. Upon fusion of the untranslated regions of StBEL5 to a β‐glucuronidase marker, translation in tobacco protoplasts was repressed by those constructs containing the 3′ untranslated sequence. The untranslated regions of the StBEL5 mRNA are involved in mediating its long‐distance transport and in controlling translation. The 3′ untranslated sequence contains an abundance of conserved motifs that may serve as binding motifs for RNA‐binding proteins. Because of their presence in the phloem sieve tube system, their unique untranslated region sequences and their diverse RNA accumulation patterns, the family of BEL1‐like RNAs from potato represents a valuable model for studying the long‐distance transport of full‐length mRNAs and their role in development.
On the initial mass function and tilt of the fundamental plane of massive early-type galaxies
Authors: Grillo C. , Gobat R.
Published: January 2010

We investigate the most plausible stellar initial mass function (IMF) and the main origin of the tilt of the fundamental plane (FP) for old, massive early-type galaxies. We consider a sample of 13 bright galaxies of the Coma cluster and combine our results with those obtained from a sample of 57 lens galaxies in the same luminous mass range. We estimate the luminous mass and stellar mass-to-light ratio values of the sample galaxies by fitting their Sloan Digital Sky Survey multiband photometry with composite stellar population models computed with different dust-free, solar-metallicity templates and IMFs. We compare these measurements and those derived from two-component orbit-based dynamical modelling. The photometric and dynamical luminous mass estimates of the galaxies in our sample are consistent, within the errors, if a Salpeter IMF is adopted. On the contrary, with a Kroupa or Chabrier IMF the two luminous mass diagnostics differ at a more than 4σ level. For the massive Coma galaxies, their stellar mass-to-light ratio scales with luminous mass as the corresponding effective quantities are observed to scale on the FP. This indicates that the tilt of the FP is primarily caused by stellar population properties. We conclude that old, massive lens and non-lens early-type galaxies obey the same luminous and dynamical scaling relations, favour a Salpeter IMF, and suggest a stellar population origin for the tilt of the FP. The validity of these results for samples of early-type galaxies with different age and mass properties still remains to be tested.
The role of lithium production in massive AGB and super-AGB stars for the understanding of multiple populations in globular clusters
Authors: Ventura P. , D'Antona F.
Published: January 2010

Lithium is made up in the envelopes of massive asymptotic giant branch (AGB) stars through the process of Hot Bottom Burning. In globular clusters, this processing is one possible source of the hot-CNO burning whose nuclear products are then ejected into the intracluster medium and take part in the formation of a second stellar generation, explaining the peculiar distribution of chemical elements among the cluster stars. We discuss the lithium yields from AGB stars in the mass range 3 to ∼6.3 M⊙, and from super-AGB stars of masses in the range 6.5–9 M⊙ for metallicity Z= 10−3. The qualitative behaviour of these yields is discussed in terms of the physical structure of the different masses. Although many uncertainties affect the other yields of these stars (e.g. O, Na and Mg), even larger uncertainties affect the lithium yield, as it depends dramatically on the adopted description of mass-loss. When we adopt our standard mass-loss formulation, very large yields are obtained especially for the super-AGB stars, and we discuss their possible role on the lithium abundance of second generation stars in globular clusters.
Repair of a canine forelimb skin deficit by microvascular transfer of a caudal superficial epigastric flap
Authors: Lewin G. A. , Smith J. H.
Published: January 2010

Extensive skin loss from the forelimb of a Border collie was repaired by a microvascular caudal superficial epigastric flap, with secondary meshing of the flap to increase coverage. The caudal superficial epigastric artery and vein were anastomosed to the brachial artery and vein. End‐to‐end anastomosis to the brachial artery and vein did not compromise peripheral blood flow, and no flap necrosis was observed after subsequent limited meshing of the flap.
Management of concurrent patellar luxation and cranial cruciate ligament rupture using modified tibial plateau levelling
Authors: Langenbach Anke , Marcellin‐Little Denis J.
Published: January 2010

Objectives: To evaluate a novel surgery aimed at managing concurrent medial patellar luxation (MPL) and cranial cruciate ligament (CCL) ruptures in dogs weighing more than 30 kg.

Methods: Tibial plateau levelling osteotomy (TPLO) and femoral trochleopasty were performed. The principal tibial fragment was laterally translated by 3 to 6 mm and was externally and abaxially rotated to create a wedge measuring 1·5 to 2·5 mm at the medial and cranial aspect and 1 to 3 mm at the medial and distal aspect of the tibial plateau fragment. The fragments were stabilised with a narrow TPLO plate.

Results: Thirteen surgeries were performed in 12 dogs with a mean weight of 39·8 kg. The mean postoperative tibial plateau slope was 8·1°. Additional surgery was required in two cases, one due to failure of fixation and another due to screw breakage. The mean lameness score was 3·5 (out of 5) before surgery, 0·7 after 8 to 12 weeks, and 0·3 at final follow‐up. Median follow‐up was 1115 days (range, 270 to 2040 days). No patella luxated after surgery.

ClinicalSignificance: MPL and CCL ruptures may be successfully managed by performing a TPLO and simultaneously altering the relationship of the principal and tibial plateau fragments during surgery.
Inspiratory stridor secondary to palatolingual myokymia in a Maltese dog
Authors: Vanhaesebrouck A. E. , Bhatti S. F. , Bavegems V. , Gielen I. M. , Van Soens I. , Vercauteren G. , Polis I. , Van Ham L. M.
Published: January 2010

A nine‐year‐old male Maltese dog was presented with an eight‐month history of inspiratory stridor leading to exertional dyspnoea and cyanosis. Myokymic contractions in the palatolingual muscles were noticed and confirmed by electromyography. Brain computer tomography‐scan showed ventricular dilatation. Cerebrospinal fluid analysis revealed a slightly elevated protein level. Treatment with slow‐release phenytoin was unsuccessful and symptoms gradually worsened over the next nine months. At post‐mortem examination a small pituitary adenoma was found. Apart from a single canine report of facial myokymia, this is the only other description of spontaneous focal myokymia in animals. Palatolingual myokymia has only been reported in one human being. Although the co‐occurrence with a pituitary adenoma might be incidental, a paraneoplastic pathogenetic mechanism is proposed. Its unique clinical presentation adds a new, albeit uncommon, syndrome to the differential diagnosis of upper airway complaints in dogs.
English springer spaniels with significant bradyarrhythmias—presentation, troponin I and follow‐up after pacemaker implantation
Authors: Fonfara S. , Loureiro J. F. , Swift S. , James R. A. , Pereira Y. Martinez , Lopez‐Alvarez J. , Summerfield N. , Dukes‐McEwan J.
Published: January 2010

Objectives: English springer spaniels (ESS) are one of the most frequently presented breeds for pacemaker implantation in the UK and may do so at an early age. In comparison to dogs of other breeds (non‐ESS) presenting for pacemaker implantation, cardiac troponin I (cTnI), the outcome and survival of ESS were investigated.

Methods: Case records of dogs receiving pacemaker implantation were retrospectively reviewed.

Results: Between September 2004 and October 2008, 58 dogs were presented to the Small Animal Teaching Hospital, University of Liverpool for pacemaker implantation. ESS (n=10) was the second most commonly presented breed. ESS were significantly younger than non‐ESS (P=0·022). cTnI values were elevated on presentation and a significant reduction was present after pacemaker implantation (P=0·008) in all dogs. No significant difference in initial cTnI was identified comparing ESS and non‐ESS (P=0·45) and median survival times were similar (P=0·37).

ClinicalSignificance: ESS may be predisposed to bradyarrhythmias requiring pacemaker implantation. They present at a significantly younger age than non‐ESS. Survival times between ESS and non‐ESS were similar, despite ESS being paced at a younger age. However, pacemaker implantation is recommended in ESS as median survival times of 30 months with a good quality of life were achieved.
N‐terminal pro B‐type natriuretic peptide and left ventricular diameter independently predict mortality in dogs with mitral valve disease
Authors: Moonarmart W. , Boswood A. , Fuentes V. Luis , Brodbelt D. , Souttar K. , Elliott J.
Published: January 2010

Objectives: To determine whether natriuretic peptide concentrations would predict all cause mortality in dogs with degenerative mitral valve disease.

Methods: One hundred dogs with naturally occurring degenerative mitral valve disease were prospectively recruited for this longitudinal study. Analysis of outcome was undertaken for 73 dogs for which the outcome was known. Dogs underwent physical examination, electrocardiography and echocardiography. Natriuretic peptide concentrations were measured byEnzyme‐linked immunosorbent assay. The ability of natriuretic peptide concentrations, clinical, electrocardiographic and echocardiographic data, to predict all cause mortality was determined using univariable and multivariable Cox proportional hazards analyses.

Results: Thirty dogs died during the period of follow‐up. Two variables were independently predictive of all cause mortality; these were the normalised left ventricular end‐diastolic diameter and the N‐terminal pro B‐type natriuretic peptide concentration. An increase of the left ventricular end‐diastolic diameter by 0.1 increased the hazard of all cause mortality by 20% (95% confidence interval: 4 to 37%, P=0.01) and a 100 pmol/l increase in N‐terminal pro B‐type natriuretic peptide increased the hazard by 7% (95 confidence interval: 2 to 11%, P=0.003).

ClinicalSignificance: N‐terminal pro B‐type natriuretic peptide concentration and left ventricular end‐diastolic diameter are significantly and independently predictive of all cause mortality in dogs with degenerative mitral valve disease.
Owner's perception of carboplatin in conjunction with other palliative treatments for cancer therapy
Authors: Bowles D. B. , Robson M. C. , Galloway P. E. , Walker L.
Published: January 2010

Objectives: To determine owner's perception of their pet's quality of life during treatment with carboplatin for a variety of canine and feline neoplasms.

Methods: Owners were contacted via a postal questionnaire and asked questions regarding their perception of chemotherapy in pets and their perception of carboplatin treatment in their pet.

Results: Twenty‐eight (59%) of owners responded to the questionnaire. Forty‐three percent of owners had not considered chemotherapy in pets before treatment; however, after treatment, 89% of owners supported its use. Sixteen (57%) patients had mild to severe side effects. Most patients experienced mild side effects, including lethargy and loss of appetite. Quality of life during treatment was reduced compared with prediagnosis quality of life however at its best was significantly improved compared with pretreatment quality of life. Eighty‐nine per cent of respondents did not regret treating their pet.

ClinicalSignificance: Carboplatin is well tolerated by both owners and pets. Most patients have either no side effects or experience mild lethargy or inappetence. Carboplatin treatment, either alone or in conjunction with other medications, should be considered as a palliative treatment in both dogs and cats with susceptible neoplasms.
Water Activity and Temperature Effects on Fungal Growth and Ochratoxin A Production by Ochratoxigenic Aspergillus carbonarius Isolated from Tunisian Grapes
Authors: Lasram Salma , Oueslati Souheib , Valero Ana , Marin Sonia , Ghorbel Abdelwahed , Sanchis Vicente
Published: January 2010

ABSTRACT:  This study investigated the effects of temperature (15 to 37 °C) and water activity (0.90 to 0.99) on the growth and production of ochratoxin A (OTA) by Aspergillus carbonarius cultured on synthetic nutrient medium (SNM) after 5 and 10 d of incubation. Total of 8 ochratoxigenic A. carbonarius, isolated from vineyards located in different regions of Tunisia, were used. Growth data were modeled by the flexible model of Baranyi and growth rates at each set of conditions were obtained. For both growth and OTA production, optimal water activity was 0.99; however, optimal temperature varied. The optimal temperature for growth was 30 °C. At 37 °C, the growth rate decreased significantly (P < 0.05). Maximum toxin production occurred at temperatures in the range of 15 to 25 °C with the optimum one depending on the isolate tested. Significant amounts of OTA were produced after only 5 d of incubation. Our results showed that A. carbonarius isolated from Tunisian grapes behave as those from European and Australian grapes, as reported in the literature, although some differences in trends for growth and OTA production were observed.
Preparation and Characterization of Water/Oil/Water Emulsions Stabilized by Polyglycerol Polyricinoleate and Whey Protein Isolate
Authors: Mun Saehun , Choi Yongdoo , Rho Shin‐Joung , Kang Choon‐Gil , Park Chan‐Ho , Kim Yong‐Ro
Published: January 2010

ABSTRACT:  In this study we tried to prepare stable water‐in‐oil‐in‐water (W/O/W) emulsions using polyglycerol polyricinoleate (PGPR) as a hydrophobic emulsifier and whey protein isolate (WPI) as a hydrophilic emulsifier. At first, water‐in‐oil (W/O) emulsions was prepared, and then 40 wt% of this W/O emulsion was homogenized with 60 wt% aqueous solution of different WPI contents (2, 4, and 6 wt% WPI) using a high‐pressure homogenizer (14 and 22 MPa) to produce W/O/W emulsions. The mean size of final W/O/W droplets ranged from 3.3 to 9.9 μm in diameter depending on the concentrations of PGPR and WPI. It was shown that most of the W/O/W droplets were small (<5 μm) in size but a small population of large oil droplets (d > 20 μm) was also occasionally observed. W/O/W emulsions prepared at the homogenization pressure of 22 MPa had a larger mean droplet size than that prepared at 14 MPa, and showed a microstructure consisting of mainly approximately 6 to 7‐μm droplets. When a water‐soluble dye PTSA as a model ingredient was loaded in the inner water phase, all W/O/W emulsions showed a high encapsulation efficiency of the dye (>90%) in the inner water phase. Even after 2 wk of storage, >90% of the encapsulated dye still remained in the inner water phase; however, severe droplet aggregation was observed at relatively high PGPR and WPI concentrations.
Inhibition of Heterocyclic Amine Formation in Beef Patties by Ethanolic Extracts of Rosemary
Authors: Puangsombat Kanithaporn , Smith J. Scott
Published: January 2010

ABSTRACT:  Heterocyclic amines (HCAs) are mutagenic compounds formed during cooking muscle foods at high temperature. Inhibition of HCAs by rosemary extracts were evaluated with beef patties cooked at 191 °C (375 °F) for 6 min each side and 204 °C (400 °F) for 5 min each side. Five rosemary extracts extracted with different solvents were used in this study: extract 100W (100% water), 10E (10% ethanol), 20E (20% ethanol), 30E (30% ethanol), and 40E (40% ethanol). The 5 extracts were directly added to beef patties at 3 levels (0.05%, 0.2%, and 0.5%) before cooking and HCA contents were extracted and quantified. All of the patties contained 2‐amino‐3,8‐dimethylimidazo [4,5‐f]quinoxaline (MeIQx), and 2‐amino‐1‐methyl‐6‐phenylimidazo [4,5‐b]pyridine (PhIP). There was no statistical difference in the inhibition of HCAs in the 0.05%, 0.2%, and 0.5% rosemary extracts. All rosemary extracts significantly decreased the levels of MeIQx and PhIP at both cooking conditions. When cooking at 204 °C (400 °F) for 5 min each side, rosemary extracts 10E and 20E were superior to rosemary extracts 100W, 30E, and 40E in inhibiting HCA formation. Rosemary extract 20E showed the greatest inhibition of MeIQx (up to 91.7%) and PhIP (up to 85.3%). The inhibiting effect of rosemary extracts on HCA formation corresponded to their antioxidant activity based on a DPPH scavenging assay. Rosemary extract 10E and 20E contain a mixture of rosmarinic acid, carnosol, and carnosic acid. It is possible that these compounds might act synergistically in inhibiting the formation of HCAs.
ORIGINAL ARTICLE: Role of mean platelet volume as discriminating guide for bone marrow disease in patients with thrombocytopenia
Authors: CHANDRA H. , CHANDRA S. , RAWAT A. , VERMA S. K.
Published: January 2010

Recently, platelet indices have been evaluated to determine their utility in knowing the mechanism of thrombocytopenia. This study was conducted to analyze the role of mean platelet volume (MPV) as a guide or an indicator for bone marrow disease in thrombocytopenic patients. All the patients with thrombocytopenia for various causes followed by bone marrow examination were divided into two groups, one group with and another without bone marrow disease, depending on pathophysiology. The MPV was statistically analyzed in both the groups to assess its role as guide for bone marrow disease in these patients. Mean MPV (average score of all individual mean values in patients) in the group with bone marrow disease was 7.3 fl, while in the group without bone marrow disease, it was 8.62 fl. Although the difference in MPV in the two groups of with (including megaloblastic anemia) and without bone marrow involvement was statistically significant (P value <0.001), its sensitivity and specificity scores as observed by receptor operating characteristic (ROC) curve at cut‐off of <8.15 fl were not highly sufficient (67.7% sensitive and 65% specific). The study concluded that although MPV can be used as an initial hint for bone marrow disease in thrombocytopenic patients, it has limited sensitivity and specificity. The differentiation of megaloblastic anemia from other causes of pancytopenia involving the marrow requires bone marrow examination rather than using MPV as an indicator. Bone marrow examination remains the gold standard for discriminating hypoproductive type of thrombocytopenia from the hyperdestructive one. In addition, the role of other platelet indices should also be assessed further to know a better indicator for bone marrow involvement in thrombocytopenic patients.
Cardioprotective Effects of Angiotensin II Type 1 Receptor Blockade with Olmesartan on Reperfusion Injury in a Rat Myocardial Ischemia‐Reperfusion Model
Authors: Dai Wangde , Hale Sharon L. , Kay Gregory L. , Jyrala Aarne J. , Kloner Robert A.
Published: January 2010

We determined the effects of olmesartan on infarct size and cardiac function in a rat ischemia/reperfusion model. Rats underwent 30 min of left coronary artery (CA) occlusion followed by 2 h of reperfusion. In protocol 1, the rats received (by i.v.) 1 mL of vehicle at 10 min after CA occlusion (Group 1, n = 15); olmesartan (0.3 mg/kg) at 10 min after CA occlusion (Group 2, n = 15); 1 mL of vehicle at 5 min before CA reperfusion (Group 3, n = 15); or olmesartan (0.3 mg/kg) 5 min before CA reperfusion (Group 4, n = 15). In protocol 2, the rats received (by i.v.) 1 mL of vehicle at 5 min before CA reperfusion (Group 5, n = 21); or olmesartan (3 mg/kg) at 5 min before CA reperfusion (Group 6, n = 21). Systemic hemodynamics, left ventricular (LV) function, LV ischemic risk zone, no‐reflow zone, and infarct size were determined. In protocol 1, olmesartan (0.3 mg/kg) did not affect blood pressure (BP), heart rate, LV ± dp/dt or LV fractional shortening during the experimental procedure, and did not alter no‐reflow or infarct size. In protocol 2, olmesartan (3 mg/kg) significantly reduced infarct size to 21.7 ± 4.1% from 34.3 ± 4.1% of risk zone in the vehicle group (P= 0.035), but did not alter the no‐reflow size. Prior to CA reperfusion, olmesartan (3 mg/kg) significantly reduced mean BP by 22% and LV ±dp/dt, but did not affect heart rate. At 2 h after reperfusion, olmesartan significantly decreased heart rate by 21%, mean BP by 14%, and significantly increased LV fractional shortening from 54.1 ± 1.4% to 61.3 ± 1.6% (P= 0.0018). Olmesartan significantly reduced myocardial infarct size and improved LV contractility at a dose (3 mg/kg) with systemic vasodilating effects but not at a lower dose (0.3 mg/kg) without hemodynamic effects.
Prevention of Atrial Fibrillation in Cardiac Surgery: Time to Consider a Multimodality Pharmacological Approach
Authors: Ho Kwok M. , Lewis John P.
Published: January 2010

Atrial fibrillation (AF) is very common within the first 5 days of cardiac surgery. It is associated with significant morbidity including stroke, ventricular arrhythmias, myocardial infarction, heart failure, acute kidney injury, prolonged hospital stay, and also short‐ and long‐term mortality. The underlying mechanisms of developing AF after cardiac surgery are multifactorial; risk factors may include advanced age, withdrawal of beta‐blockers and angiotensin‐converting‐enzyme inhibitors, valve surgery, obesity, increased left atrial size, and diastolic dysfunction. There are many pharmacological options in preventing AF, but none of them are effective for all patients and they all have significant limitations. Beta‐blockers may reduce the incidence of AF by more than a third, but bradycardia, hypotension, or exacerbation of heart failure often limit their utility postoperatively. Recent evidence suggests that class III antiarrhythmic drugs, sotalol and amiodarone, are more effective than beta‐blockers, but they both share similar hemodynamic side effects of beta‐blockers. Magnesium, antiinflammatory drugs such as statins, omega fatty acids, and low‐dose corticosteroids also have some efficacy and they have the advantages of not causing significant hemodynamic side effects. Data on effectiveness of calcium channel blockers, digoxin, alpha‐2 agonists, sodium nitroprusside, and N‐acetylcysteine are more limited. Because the pathogenesis of AF is multifactorial, a combination of drugs with different pharmacological actions may have additive or synergistic effect in preventing AF after cardiac surgery. Randomized controlled trials evaluating the effectiveness of a multimodality pharmacological approach in patients at high‐risk of AF after cardiac surgery are needed.
The Usefulness of Chronic Heart Failure Treatments in Chronic Cardiac Graft Failure
Authors: Najam Osman , Yonan Nizar , Williams Simon G. , Shaw Steven M.
Published: January 2010

Following cardiac transplantation, registry data has demonstrated a gradual improvement in survival over the last several decades, which is testament to continual improvement in aftercare strategy. However, a significant number of patients will eventually develop a new syndrome of chronic heart failure, owing to the multitude of physiological processes that occur after transplantation. This condition, referred to as chronic graft failure (CGF) should be regarded as a unique illness rather than one that is simply analogous with chronic heart failure. In particular, the unique pathophysiological (and pharmacological) environment in the setting of CGF presents a challenging situation to the transplant physician. There is uncertainty over which treatments to offer given a paucity of clinical trial data to support the use of standard heart failure treatments in CGF. In this review, we discuss which chronic heart failure treatments could be considered in the setting of CGF based on their mechanisms of action, benefits within the native heart failure setting, and the relevant issues within the posttransplant environment.
Expansion of CD4+CD25+FoxP3+ regulatory T cells in hepatitis C virus‐related chronic hepatitis, cirrhosis and hepatocellular carcinoma
Authors: Yoshizawa Kai , Abe Hiroshi , Kubo Yasuhito , Kitahara Takuya , Aizawa Ryoichi , Matsuoka Mika , Aizawa Yoshio
Published: January 2010

Aim:  Regulatory T (Treg) cells may play a pivotal role in the persistence of hepatitis C virus (HCV) infection and the development of hepatocellular carcinoma (HCC). Therefore, we examined their frequency in peripheral blood from patients with HCV‐positive chronic hepatitis (CH), cirrhosis (LC) and HCC.

Methods:  Treg cells were identified as CD4+, CD25+ and FoxP3+ T lymphocytes using three‐color FACS. The frequency of Treg cells was expressed as a percentage of the total CD4+ T lymphocytes, and the phenotype of Treg cells was examined using CD45RA.

Results:  Treg cells were significantly increased in CH (5.88 ± 0.19%, n = 76; P < 0.01), LC (6.10 ± 0.28%, n = 40; P < 0.001) and HCC (6.80 ± 0.30%, n = 57; P < 0.0001) compared to healthy control (5.13 ± 0.25%, n = 31). However, Treg cells were not increased with the progression of fibrosis or the grade of inflammations. Treg cells were slightly increased in early‐stage HCC (6.91 ± 0.40%) compared with advanced‐stage HCC (6.58 ± 0.39%), but these results were not statistically significant. In a serial examination, a distinct increase in Treg cells after local therapy for early‐stage HCC was a hallmark of early recurrence. Most expanded Treg cells in HCC were CD45RA‐, suggesting that a memory‐type Treg population had differentiated in the periphery and not in the thymus.

Conclusion:  We observed an increase in Treg cells in HCV‐related chronic liver disease, particularly in HCC, and these cells were shown to be memory‐type Treg cells.
Megestrol and embryonic extracts in the treatment of advanced hepatocellular carcinoma: A prospective randomized trial in the pre‐sorafenib era
Authors: Giacomin Anna , Sergio Adriana , Vanin Veronica , Tartaro Pietro , Paccagnella Daniela , Mazzucco Mauro , Farinati Fabio
Published: January 2010

Background:  Patients with advanced hepatocellular carcinoma (HCC) achieved significant results by the new treatment with sorafenib (a multi‐tyrosine kinase inhibitor), but, because it has been tested mainly in Child A cirrhosis, patients with impaired liver function are not eligible for the treatment.

Methods:  This study was an open label phase III randomized trial comparing Synchro‐Levels (Alphrema, Varese, Italy) and megestrol, with a 2:1 design, in patients with advanced HCC, planned before the sorafenib registration. End‐points were objective response and impact on performance status (primary) and biochemical response (secondary).

Results:  The patients enrolled were 61 (43 men, 18 women; Child A in 28 [48%] and B in 33 [52%]). Forty‐three were assigned to Synchro‐Levels, 18 to megestrol. Most patients had multifocal disease (75% in megestrol and 59% in Synchro‐Levels) and there was a significant difference in tumor burden, with more advanced disease in the megestrol arm (P = 0.0002). At 3 months, tumor burden was more frequently stable with megestrol, while performance status was significantly better in patients treated with Synchro‐Levels. At 6 months, α‐fetoprotein was more frequently stable or reduced with megestrol. An objective response was observed in a megestrol‐treated patient. Mortality was significantly lower and long‐term survival significantly more frequent with megestrol.

Conclusion:  Megestrol treatment shows good results in advanced HCC and could become part of best supportive care in patients not suitable for other treatments, that, despite sorafenib, remain an important share.
Docetaxel inhibits progression of human hepatoma cell line in vitro and is effective in advanced hepatocellular carcinoma
Authors: Yata Yutaka , Xue Feng , Takahara Terumi , Kudo Hiroshi , Hirano Katsuharu , Yasumura Satoshi , Minemura Masami , Scanga Andrew E , Sugiyama Toshiro
Published: January 2010

Background:  Current chemotherapy for advanced hepatocellular carcinoma (HCC) is insufficient; only sorafenib has been proven to provide a modest survival benefit. A future direction of chemotherapy is to tailor treatment based on the chemosensitivity of each individual tumor. By doing so, only patients who stand to benefit from therapy will be exposed to potential side‐effects and morbidity. Although the use of docetaxel (DTX) for the treatment of lung, breast and gastric cancer has been reported, there are few reports about its use in the setting of HCC.

Methods:  To examine the efficacy of DTX for HCC, we established a human hepatoma cell line (TK cell) from the patient's malignant ascites from peritoneal carcinomatosis and treated it with DTX in vitro.

Results:  After we confirmed the efficacy of DTX in vitro, we treated our patient with DTX with positive results.

Conclusion:  In this study, we present a therapeutic approach by using DTX that supports the potential usefulness of personalized medicine in vitro and demonstrates it clinically.
Accelerated expression of a Myc target gene Mina53 in aggressive hepatocellular carcinoma
Authors: Ogasawara Sachiko , Komuta Mina , Nakashima Osamu , Akiba Jun , Tsuneoka Makoto , Yano Hirohisa
Published: January 2010

Aim:  Expressions of the myc target genes Mina53 and mimitin are high in esophageal squamous cell carcinoma and colon cancer, and their relationship to cell proliferation and patient prognosis has been reported. Because c‐myc gene expression is closely related to hepatocellular carcinoma (HCC) growth or formation and/or maintenance, we examined the Mina53 and mimitin expressions in HCC.

Methods:  Surgically resected 53 HCC tissues were immunohistochemically examined for Mina53 and mimitin expressions and their relationship to clinicopathological factors.

Results:  Diffuse Mina53 expression was observed in the nuclei of cancer cells in the tumor nodule, but was often strong at the periphery of tumor nodules. Diffuse or scattered expression of mimitin was observed in the cytoplasm of HCC cells in tumor nodules. Mina53 expression was higher in poorly differentiated HCC than in well‐differentiated HCC, and significant relationship to histological grade was observed. The cases with a high Mina53 expression also had a high expression of a proliferation marker MIB‐1. This suggested the involvement of Mina53 in cell proliferation. Mina53 expression was high in the tumors of >2 cm of diameter than in ≤2 cm (P < 0.01). Mimitin expression tended to be high in tumors of >2 cm, but no significant relationship was observed either to histological grade, MIB‐1 expression, or the other clinicopathologic factors.

Conclusions:  Our findings suggested that Mina53 expression is accelerated in HCC with a lower histological grade, with cell proliferation capability, or with a larger diameter, and Mina53 is related to biological malignancy of HCC.
Phase I/II study of a fine‐powder formulation of cisplatin for transcatheter arterial chemoembolization in hepatocellular carcinoma
Authors: Moriguchi Masamichi , Takayama Tadatoshi , Nakamura Masahiko , Aramaki Osamu , Higaki Tokio , Nakayama Hisashi , Ohkubo Takao , Fujii Masashi
Published: January 2010

Aim:  The clinical feasibility of transcatheter arterial chemoembolization (TACE) with fine‐powder cisplatin (CDDP) in patients with hepatocellular carcinoma (HCC) has not been investigated. A phase I/II study was conducted to investigate the safety and tolerability of fine‐powder CDDP when it was used with lipiodol and gelatin sponge particles for TACE.

Methods:  Fine‐powder CDDP emulsified in lipiodol was injected into tumor arteries. Embolization was subsequently performed with gelatin sponge particles. The CDDP dose was started at 45 mg/m2 (level 1) and increased to 65 mg/m2 in 10 mg/m2 increments.

Results:  Thirteen patients were enrolled in phase I study since no dose limiting toxicity was observed in any patients, even in seven patients at level 3 (65 mg/m2), the recommended dose was 65 mg/m2. The major adverse event was grade 3 thrombocytopenia, which occurred in 8% of patients. The incidence of hematological toxicities was 15% for leukocytopenia, 84% for thrombocytopenia, and 84% for anemia. Increased serum total bilirubin was observed in 54% and increased aspartate aminotransferase or alanine aminotransferase in all patients. All digestive tract symptoms (nausea 77%, anorexia 84%, vomiting 31%) were grade 2 or lower. Total adverse events were grade 3 or higher in 44%. The response rate in 19 patients who received the recommended dose was 21%.

Conclusions:  TACE with a fine‐powder formulation of CDDP at a dose of 65 mg/m2 is well tolerated in patients with unresectable HCC.
The Role of Field Experience in Elementary Preservice Teachers' Self‐Efficacy and Ability to Connect Research to Practice
Authors: McDonnough Jacqueline T. , Matkins Juanita Jo
Published: January 2010

Though the importance of including practicum experiences in programs for the preparation of elementary preservice teachers is generally accepted, the nature of these experiences on the development of skills in teaching science can vary greatly. This study compares the effect of variations in field experiences at two institutions, one which included a practicum that was not connected to the science methods course and instructor and the other where the practicum was concurrent with and taught by the methods instructor. Interview data and results of the STEBI‐B were collected across four years, with a total n = 129. The concurrent, embedded practicum yielded consistent increases in self‐efficacy across the semesters. Also after the embedded practicum, preservice teachers showed greater understanding in research‐based science teaching practices.
An Evaluation of a High Altitude Solar Radiation Platform
Authors: Redi S. , Aglietti G. S. , Tatnall A. R. , Markvart T.
Published: January 2010

This paper presents a preliminary assessment of the potential advantage that a high altitude solar collector could bring compared with the traditional ground based photovoltaic systems. This advantage mainly derives from the reduced attenuation of the solar radiation as it travels through the atmosphere especially if clouds are present above the location considered. A sun beam traveling through clear atmosphere is considered first using an existent model to calculate the daily irradiation at different altitudes in clear sky conditions. The results obtained are then integrated with experimental data describing cloud distributions versus altitude, and finally the contribution of the diffused radiation is also included to give a realistic evaluation of the total actual irradiation at a specific altitude. The results are obtained for a specific location in the UK, where the experimental data have been acquired. The general conclusions, however, involving the potential of high altitude solar collectors, can be extended to other countries in Europe with similar climates. Finally, the main issues involved in the design and development of a flying platform for the exploitation of the solar energy are presented and the technical feasibility of the system is discussed.
Solar Water Disinfection Studies With Supported TiO2 and Polymer-Supported Ru(II) Sensitizer in a Compound Parabolic Collector
Authors: Rodríguez Juan , Jorge Clido , Zúñiga Patricia , Palomino Javier , Zanabria Pedro , Ponce Silvia , Solís José L. , Estrada Walter
Published: January 2010

Solar water disinfection was performed using TiO2 and a Ru(II) complex as fixed catalysts located in a compound parabolic collector photoreactor. Studies were performed in the laboratory as well as at a greenfield site. Under laboratory conditions, natural water contaminated with cultured bacteria was photocatalytically treated and the influence of the photolysis as well as of both catalysts was studied. Experiments were performed with contaminated water flowing at 12 l/min; under these conditions, photocatalytic experiments performed with a supported heterogeneous photocatalyst (Ahlstrom paper impregnated with TiO2) showed it to be effective in degrading bacteria in water. The Ru complex catalyst, however, showed no clear evidence for disinfecting water, and its efficiency was comparable to the simple photolysis. Under on-site experiments, bacteria contaminated water from the Yaurisque river at Cusco, Peru was treated. As a general trend, after photocatalytic treatment a reduction in the E-coli population present in water was observed. Whenever disinfection was achieved in the experiments, no regrowth of bacteria was observed after 24 h. However, a reduction in the prototype efficiency was observed both in laboratory and on-site experiments. This was ascribed to aging of the photocatalyst as well as due to the deposition of particles onto its surface. In cases in which incomplete disinfection resulted, a low rate of E-coli growth was observed 24 h after ending the experiment. However, pseudomones seem to be resistant to the treatment.
Applications of Low-Speed Dynamic-Stall Model to the NREL Airfoils
Authors: Sheng Wanan , Galbraith Roderick A. McD. , Coton Frank N.
Published: January 2010

National Renewable Energy Laboratory, USA (NREL) airfoils have been specially developed for wind turbine applications, and projected to yield more annual energy without increasing the maximum power level. These airfoils are designed to have a limited maximum lift and relatively low sensitivity to leading-edge roughness. As a result, these airfoils have quite different leading-edge profiles from airfoils applied to helicopter blades, and thus, quite different dynamic-stall characteristics. Unfortunately for wind turbine aerodynamics, the dynamic-stall models in use are still those specially developed and refined for helicopter applications. A good example is the Leishman–Beddoes dynamic-stall model, which is one of the most popular models in wind turbine applications. The consequence is that the application of such dynamic-stall model to low-speed cases can be problematic. Recently, some specific dynamic-stall models have been proposed or tuned for the cases of low Mach numbers, but their universality needs further validation. This paper considers the application of the modified dynamic low-speed stall model of Sheng et al. (“A Modified Dynamic Stall Model for Low Mach Numbers,” 2008, ASME J. Sol. Energy Eng., 130(3), pp. 031013) to the NREL airfoils. The predictions are compared with the data of the NREL airfoils tested at the Ohio State University. The current research has two objectives: to justify the suitability of the low-speed dynamic-stall model, and to provide the relevant parameters for the NREL airfoils.
Simulation and Experimental Analysis of a Solar Driven Absorption Chiller With Partially Wetted Evaporator
Authors: Albers Jan , Nurzia Giovanni , Ziegler Felix
Published: January 2010

The efficient operation of a solar cooling system strongly depends on the chiller behavior under part load conditions, since driving energy and cooling load are never constant. For this reason, the performance of a single stage, hot water driven 30 kW H2O/LiBr-absorption chiller employed in a solar cooling system with a field of 350 m2 evacuated tube collector has been analyzed under part load conditions with both simulations and experiments. A simulation model has been developed for the whole absorption chiller (Type Yazaki WFC-10), where all internal mass and energy balances are solved. The connection to the external heat reservoirs of hot, chilled, and cooling water is done by lumped and distributed UA values for the main heat exchangers. In addition to an analytical evaporator model—which is described in detail—experimental correlations for UA values have been used for the condenser, generator, and solution heat exchanger. For the absorber, a basic model based on the Nusselt theory has been employed. The evaporator model was developed, taking into account the distribution of refrigerant on the tube bundle, as well as the change in operation from a partially dry to an overflowing evaporator. A linear model is derived to calculate the wetted area. The influence of these effects on cooling capacity and coefficient of performance (COP) is calculated for three different combinations of hot and cooling water temperature. The comparison to experimental data shows a good agreement in the various operational modes of the evaporator. The model is able to predict the transition from partially dry to an overflowing evaporator quite well. The present deviations in the domain with high refrigerant overflow can be attributed to the simple absorber model and the linear wetted area model. Nevertheless, the results of this investigation can be used to improve control strategies for new and existing solar cooling systems.
Solar Concentrating Systems Using Small Mirror Arrays
Authors: Göttsche Joachim , Hoffschmidt Bernhard , Schmitz Stefan , Sauerborn Markus , Buck Reiner , Teufel Edgar , Badstübner Kathrin , Ifland David , Rebholz Christian
Published: January 2010

The cost of solar tower power plants is dominated by the heliostat field making up roughly 50% of investment costs. Classical heliostat design is dominated by mirrors brought into position by steel structures and drives that guarantee high accuracies under wind loads and thermal stress situations. A large fraction of costs is caused by the stiffness requirements of the steel structure, typically resulting in ∼20 kg/m2 steel per mirror area. The typical cost figure of heliostats (figure mentioned by Solucar at Solar Paces Conference, Seville, 2006) is currently in the area of 150 €/m2 caused by the increasing price of the necessary raw materials. An interesting option to reduce costs lies in a heliostat design where all moving parts are protected from wind loads. In this way, drives and mechanical layout may be kept less robust, thereby reducing material input and costs. In order to keep the heliostat at an appropriate size, small mirrors (around 10×10 cm2) have to be used, which are placed in a box with a transparent cover. Innovative drive systems are developed in order to obtain a cost-effective design. A 0.5×0.5 m2 demonstration unit will be constructed. Tests of the unit are carried out with a high-precision artificial sun unit that imitates the sun’s path with an accuracy of less than 0.5 mrad and creates a beam of parallel light with a divergence of less than 4 mrad.
The Performance of Wind Turbine Smart Rotor Control Approaches During Extreme Loads
Authors: Lackner Matthew A. , van Kuik Gijs A. M.
Published: January 2010

Reducing the loads experienced by wind turbine rotor blades can lower the cost of energy of wind turbines. “Smart rotor control” concepts have emerged as a solution to reduce fatigue loads on wind turbines. In this approach, aerodynamic load control devices are distributed along the span of the blade, and through a combination of sensing, control, and actuation, these devices dynamically control the blade loads. While smart rotor control approaches are primarily focused on fatigue load reductions, extreme loads on the blades may also be critical in determining the lifetime of components, and the ability to reduce these loads as well would be a welcome property of any smart rotor control approach. This research investigates the extreme load reduction potential of smart rotor control devices, namely, trailing edge flaps, in the operation of a 5 MW wind turbine. The controller utilized in these simulations is designed explicitly for fatigue load reductions; nevertheless its effectiveness during extreme loads is assessed. Simple step functions in the wind are used to approximate gusts and investigate the performance of two load reduction methods: individual flap control and individual pitch control. Both local and global gusts are simulated. The results yield important insight into the control approach that is utilized, and also into the differences between using individual pitch control and trailing edge flaps for extreme load reductions. Finally, the limitation of the assumption of quasisteady aerodynamic behavior is assessed.
A Microsolar Collector for Hydrogen Production by Methanol Reforming
Authors: Zimmerman Raúl , Morrison Graham , Rosengarten Gary
Published: January 2010

Proton exchange membrane fuel cells (PEMFCs) are good candidates for portable energy sources with a fast response to load changes, while being compact as a result of their capability to provide a high power density. Hydrogen constitutes the fuel for the PEMFC and can be obtained in situ to avoid transportation and safety problems. An efficient method to produce hydrogen is by methanol steam reforming in a microreactor, an endothermic reaction for which the highest efficiency occurs between 250°C and 300°C. Different methods have been used to reach and maintain these temperatures including electrical heaters and exothermic reactions. We propose to use solar energy to increase the efficiency of the microreactor while taking advantage of a free renewable energy source. The microchannels, where the water-methanol mixture flows, are insulated from the surroundings by a thin vacuum layer coated with a selective material. This coating has a high absorptance for short wavelength incoming radiation and low emittance for infrared radiation, reducing the heat losses. By using these coated insulation layers, the fluid temperature in the microchannels is predicted to be higher than 250°C. Hence, it is expected that the solar-powered microreactor will produce hydrogen with a higher overall efficiency than the present reactors by taking advantage of the solar radiation.
Autoderivation of Topological Graphs for Type Synthesis of Planar 3DOF Parallel Mechanisms
Authors: Lu Yi , Ding Ling , Yu Jianping
Published: January 2010

The autoderivation of valid topological graph (TGs) of planar 3DOF parallel mechanisms is studied systematically based on topology embryonic graphs (TEGs) and arrays. First, some TEGs without any binary links are constructed, some paths with only binary links are distributed over the TEGs, and some valid TGs of the planar 3DOF PMs are derived. Second, a complicated derivation of the TG is transformed into an easy derivation of array. Third, some programs are compiled in VB, all valid arrays corresponding to nonisomorphic TGs are derived automatically, and some invalid arrays corresponding to the isomorphic TGs and invalid TGs are determined by compiled programs. Finally, many valid TGs of planar 3DOF PMs with various basic links are derived from valid arrays.