bluuebunny/crossref_metadata_2025 huggingface dataset:
Lost Mold Rapid Infiltration Forming of Mesoscale Ceramics: Part 1, Fabrication
Authors: Antolino Nicholas E. , Hayes Gregory , Kirkpatrick Rebecca , Muhlstein Christopher L. , Frecker Mary I. , Mockensturm Eric M. , Adair James H.
Published: October 2008

Free‐standing mesoscale (340 μm × 30 μm × 20 μm) bend bars with an aspect ratio over 15:1 and an edge resolution as fine as a single grain diameter (∼400 nm) have been fabricated in large numbers on refractory ceramic substrates by combining a novel powder processing approach with photoresist molds and an innovative lost‐mold thermal process. The colloid and interfacial chemistry of the nanoscale zirconia particulates has been modeled and used to prepare highly concentrated suspensions. Engineering solutions to challenges in mold fabrication and casting have yielded free‐standing, crack‐free parts. Molds are fabricated using high‐aspect‐ratio photoresist on ceramic substrates. Green parts are formed using a rapid infiltration method that exploits the shear thinning behavior of the highly concentrated ceramic suspension in combination with gelcasting. The mold is thermally decomposed and the parts are sintered in place on the ceramic substrate. Chemically aided attrition milling disperses and concentrates the as‐received 3Y‐TZP powder to produce a dense, fine‐grained sintered microstructure. Initial three‐point bend strength data are comparable to that of conventional zirconia; however, geometric irregularities (e.g., trapezoidal cross sections) are present in this first generation and are discussed with respect to the distribution of bend strength.
Formation of a High Conductivity Fuel Cell Electrolyte by Pressing Diphenylsiloxane‐Based Inorganic–Organic Hybrid Particles
Authors: Daiko Yusuke , Sakakibara Saki , Sakamoto Hisatoshi , Katagiri Kiyofumi , Muto Hiroyuki , Sakai Mototsugu , Matsuda Atsunori
Published: October 2008

An inorganic–organic nanohybrid particle with a two‐dimensional chain structure, diphenylsiloxane‐silica (Ph2SiO–SiO2), was prepared by sol–gel process using diphenyldiethoxysilane (DPDES) and tetraethoxysilane (TEOS), and a high proton conducting polymer of poly(2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid) (PAMPS) was deposited on the Ph2SiO–SiO2 particles via layer‐by‐layer assembly. A flexible sheet‐like electrolyte was successfully obtained from the resulting PAMPS‐deposited particles by pressing. The proton conductivity of the sheet prepared using unmodified Ph2SiO–SiO2 particles was lower than 10−9 S/cm at 80°C. On the other hand, the PAMPS‐deposited samples showed proton conductivities ∼7 orders of magnitude higher than those of the sample prepared using unmodified particles, and their conductivity reached about 1 × 10−2 S/cm at 80°C and 80% relative humidity. This is ascribed to the PAMPS layer being concentrated at the particle interfaces, which percolated throughout the monolithic sample.
Hydrothermal Synthesis and Photocatalytic Activity of Whisker‐Like Rutile‐Type Titanium Dioxide
Authors: Kobayashi Makoto , Petrykin Valery , Kakihana Masato , Tomita Koji
Published: October 2008

Nanowhiskers of rutile‐type titanium dioxide (TiO2) were synthesized by a simple hydrothermal treatment of a water‐soluble titanium–glycolate complex at 473 K. The aspect ratio of the obtained rutile particles could be controlled by changing the concentration of the glycolic acid additive in the starting aqueous solution of the titanium complex. According to high‐resolution transmission electron microscopy, whisker‐like nanoparticles grow along the c‐axis of rutile, the side facets of which are (110), (−110), (1–10), and (−1–10). Glycolic acid controls promotion of the rutile particles in the specified direction due to its preferred adsorption on the titanium‐rich facets. Evaluation of the photocatalytic activity of the synthesized TiO2 was performed in terms of decomposition of oxalic acid in an aqueous system under ultraviolet irradiation. It turned out that this particular whisker‐like shape is responsible for the tremendous enhancement of rutile photocatalytic activity, and even rutile samples with low surface area demonstrated photocatalytic performance comparable with one of the best nanosized anatase photocatalytic materials. Therefore, it can be concluded that the (110) rutile facet plays an important role in the photocatalytic oxidation reaction, and that it exhibits higher photocatalytic activity than the (001) facet in the decomposition of oxalic acid.
Synthesis of Gadolinium‐Doped Ceria Powders by Electrolysis of Aqueous Solutions
Authors: Hirata Yoshihiro , Matsunaga Naoki , Murao Masaru
Published: October 2008

A gadolinium‐doped ceria powder was produced by electrolysis of an aqueous solution containing Ce3+ and Gd3+ ions using direct and alternating current at 4–10 V of applied voltage between two platinum wire electrodes (anode and cathode). The powders produced were identified as a gadolinium‐doped ceria solid solution by X‐ray diffraction and chemical analysis. Large porous particles 60–70 μm in size were produced under a direct current field for 15 min. On the other hand, nanoparticles 40–250 nm in size were produced for 6–12 h of electrolysis using alternating current below 20 Hz of frequency. No particles were formed in the high frequency range from 100 Hz to 1 MHz. The nucleation and growth rates of the particles depended on the frequency of the alternating current and electrolysis time applied. The Gd2O3/CeO2 ratio of the particles formed with alternating current was lower than that of the starting solution.
Densification and Cell Performance of Gadolinium‐Doped Ceria (GDC) Electrolyte/NiO–GDC Anode Laminates
Authors: Nagamori Minako , Shimonosono Taro , Sameshima Soichiro , Hirata Yoshihiro , Matsunaga Naoki , Sakka Yoshio
Published: October 2008

A thin film (60 μm thick) of a gadolinium‐doped ceria (GDC) electrolyte was prepared by the doctor blade method. This film was laminated with freeze‐dried 42 vol% NiO–58 vol% GDC mixed powder and pressed uniaxially or isostatically under a pressure of 294 MPa. This laminate was cosintered at 1100 °–1500 °C in air for 4–12 h. The laminate warped because of the difference in the shrinkage of the electrolyte and electrode during the sintering. A higher shrinkage was measured for the electrode at 1100 °–1200 °C and for the electrolyte at 1300 °–1500 °C. The increase of the thickness of anode was effective in decreasing the warp and in increasing the density of the laminated composite. The maximum electric power density with a SrRuO3 cathode using 3 vol% H2O‐containing H2 fuel was 100 mW/cm2 at 600 °C and 380 mW/cm2 at 800 °C, respectively, for the anode‐supported GDC electrolyte with 30 μm thickness.
Surface Activation of Conductive Porous Alumina by Depositing Nickel Particles
Authors: Hai Chunxi , Liu Jingjun , Watanabe Hideo , Fuji Masayoshi , Wang Feng , Takahashi Minoru
Published: October 2008

Electrically conductive porous ceramics have gained a recent surge of interests in development of high‐performance electrocatalysts. This paper mainly describes the electrochemical activation of conductive porous alumina (CPA) by depositing nickel nanoparticles as an electrocatalyst. The surface of the porous alumina was initially pretreated with mixed acids, followed by depositing nickel particles using an electroless method. Field‐emission scanning electron microscope observation and energy diffraction X‐ray spectroscopy analysis verified that Ni nanoparticles were successfully deposited onto surface of the CPA. Cyclic voltammetry and chronoamperometry analyses showed that the CPA deposited with nickel nanoparticles behaved as an efficient electrocatalyst for electrooxidation of methanol, which implied its potential application for fuel cells.
Control of Lamellae Spacing During Freeze Casting of Ceramics Using Double‐Side Cooling as a Novel Processing Route
Authors: Waschkies Thomas , Oberacker Rainer , Hoffmann Michael J.
Published: October 2008

A processing route for freeze‐casting of particle suspensions is presented, where the microstructure development during the solidification process can be controlled precisely. For this purpose, the single‐side cooling and double‐side cooling methods are compared. A procedure will be shown to control the freezing process using the double‐side cooling method. Our approach was to determine the freezing conditions in order to forecast the freezing velocity and to carry out an advanced directional solidification setup for the experimental realization. Using this setup and the theoretical knowledge, the microstructure development can be controlled during the whole freezing process over a length of several centimeters.
Preparation of Optimized Uranium and Thorium Bearing Brabantite or Monazite/Brabantite Solid Solutions
Authors: Terra Olivier , Dacheux Nicolas , Clavier Nicolas , Podor Renaud , Audubert Fabienne
Published: October 2008

The simultaneous incorporation of thorium and uranium(IV) in the rare‐earth orthophosphates from a mixture of powdered AnO2, (NH4)(H2PO4), and Ca(HPO4)·2H2O was successfully performed, leading to the formation of single‐phase Th‐brabantite (Ca0.5Th0.5PO4), U‐brabantite (Ca0.5U0.5PO4), and (Th,U)‐brabantites (Ca0.5Th0.5−yUyPO4). The repetition of several cycles composed of a grinding step (30 Hz, 15 min) and of a heat treatment (T=1200°C, 10 h, Ar atmosphere) allowed preparation of single‐phase and homogeneous compounds. The complete characterization of the samples by the means of X‐Ray powder diffraction, electron probe microanalyses, and μ‐Raman spectrometry did not reveal either the presence of minor phases or the partial oxidation of uranium(IV) into uranyl. This study also evidenced the formation of a complete Ca0.5Th0.5−yUyPO4 solid solution with the associated linear decrease of a, b, and c unit cell parameters and β increase versus the uranium mole loading. Even if the samples were found to be single phase, the significant improvement of the cation distribution in the materials was reached by the mean of the repetition of grinding/heating cycles. The same solid‐state process was applied with success to the preparation of homogeneous and single‐phase (Th,U)‐monazite/brabantite solid solutions with general formula Ln1−2xCaxThx−yUyPO4 (with 0.1≤x≤0.4 and y=x/5).
Enzyme‐Assisted Synthesis of Titania under Ambient Conditions
Authors: Katagiri Kiyofumi , Inami Hitoshi , Ishikawa Tomohide , Koumoto Kunihito
Published: October 2008

A low‐temperature procedure for the synthesis of TiO2 was developed using a water‐soluble titanium complex and enzymes. Titanium–lactate and titanium–glycolate complexes were used as precursors of TiO2. Digestive enzymes were chosen as biocatalysts for the synthesis of TiO2 in aqueous solutions. TiO2 powders were deposited from reaction solutions having optimal pH values for the enzymes to exhibit their catalytic activities for their original substrates. TiO2 has been synthesized by an enzymatic reaction in an aqueous solution under ambient conditions. The XRD measurements indicated that TiO2 powders thus obtained usually have an amorphous phase. However, after calcination at 550°C, the anatase phase was confirmed. Interestingly, the minor phase of TiO2, brookite, was found in the sample obtained from the titanium–glycolate complex catalyzed by lipase at pH 10 after calcination at 550°C.
Redox‐Control Solubility of Chromium Oxide in Soda‐Silicate Melts
Authors: Khedim Hichem , Podor Renaud , Rapin Christophe , Vilasi Michel
Published: October 2008

The total chromium oxide (Cr2O3) solubility is measured in Na2O–xSiO2 melts as a function of temperature (1125°<T<1250°C), glass composition (1.5<x<3.5), and oxygen fugacity (−15<fO2<−0.61) using a closed and single‐use reactor. The presence of Cr(II), Cr(III), and Cr(VI) species is evidenced and their respective contributions in the total Cr content dissolved in the melt are determined. The experimental results are described using a model of chromium chemistry in silicate melts involving dissolution, redox, and oxo‐complex reactions, whose equilibrium constants are

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A mathematical treatment, using the results obtained, allows the correlation between the proposed model and thermodynamic properties of the system. The standard enthalpies and entropies associated with the oxidation and reduction reactions are: ΔHox=−36 kJ/mol; ΔHred=208 kJ/mol; ΔSox=68 J·(mol·K)−1; and ΔSred=87 J·(mol·K)−1.
Correlation of Electrical Conductivity with Microstructure in 3Y‐TZP System: From Nano to Submicrometer Grain Size Range
Authors: Ghosh Abhijit , Dey Goutam Kumar , Suri Ashok Kumar
Published: October 2008

Nanocrystalline 3 mol% yttria‐doped tetragonal zirconia polycrystal (3Y‐TZP) has been successfully sintered to high density by both conventional and two stage sintering method. These helped in tailoring the final microstructure from nano to submicrometer range. Reduction of grain size from submicrometer to nano regime resulted in marginal increase in conductivity. Activation energy for conductance has also been found to be dependent on grain size.
Porous Silicon Nitride Ceramics Prepared by Extrusion Using Starch as Binder
Authors: Jiang Guang‐Peng , Yang Jian‐Feng , Gao Ji‐Qiang , Niihara Koichi
Published: October 2008

Green bodies of porous silicon nitride ceramics were shaped by the extrusion technique using starch simultaneously as binder during extrusion and as pore‐maker during subsequent thermal debinding. The different porosities, microstructures, and mechanical properties after the extrusion, drying, debinding, and sintering stages were investigated. The results showed that the porosity, density, microstructure, and flexural strength of samples varied greatly through the whole process stages. The resultant samples had a 160 MPa flexural strength at a porosity of 43% and a uniform fibrous interlocking microstructure consisting of well‐developed rod‐like β‐Si3N4grains. In addition, porosity, microstructure, and strength can be further tailored by sintering conditions such as the sintering nitrogen pressure. Extrusion using cheap starch as binder and pore‐maker is a promising preparation route for manufacturing cost‐effective porous silicon nitride ceramics.
An AFM/EFM Study of the Grain Boundary in ZnO‐Based Varistor Materials
Authors: Gheno Simoni M. , Kiminami Ruth H. G. A. , Morelli Márcio M. , Bellini Jusmar V. , Paulin Filho Pedro I.
Published: October 2008

Zinc oxide (ZnO)‐based varistors are metal oxide varistors whose nonlinear properties are characterized by electrical resistance that decreases as the applied field increases. The multiphasic nature of varistors leads to the formation of Schottky barriers, which are responsible for the materials' nonlinear behavior. The objective of this work was to image the potential barriers in ZnO doped with 0.5 mol% Cu and x wt% G (G is a frit and x=0, 1, and 5 wt%). The frit served to form a glassy insulating layer around the grain boundaries. Samples were sintered at 1050°C and the microstructures were analyzed using a Nanoscope IIIa atomic force microscope. The results of the electric force microscopy experiments map the electric field distribution on the surface of CuO–ZnO‐based ceramics.
Impact of Thermal Diffusion on Densification During SPS
Authors: Olevsky Eugene A. , Froyen Ludo
Published: October 2008

Spark‐plasma sintering (SPS) has the potential for rapid (with heating rates reaching several hundred K/min) and efficient consolidation of a broad spectrum of powder materials. Possible mechanisms of the enhancement of consolidation in SPS versus conventional techniques of powder processing are categorized with respect to their thermal and athermal nature. This paper analyzes the influence of thermal diffusion, which is an SPS consolidation enhancement factor of a thermal nature. The Ludwig–Soret effect of thermal diffusion causes concentration gradients in two‐component systems subjected to a temperature gradient. The thermal diffusion‐based constitutive mechanism of sintering results from the additional driving force instigated by spatial temperature gradients, which cause vacancy diffusion. This mechanism is a commonly omitted addition to the free‐surface curvature‐driven diffusion considered in conventional sintering theories. The interplay of three mechanisms of material transport during SPS is considered: surface tension‐ and external stress‐driven grain‐boundary diffusion, surface tension‐ and external stress‐driven power‐law creep, and temperature gradient‐driven thermal diffusion. It is shown that the effect of thermal diffusion can be significant for ceramic powder systems. Besides SPS, the results obtained are applicable to the ample range of powder consolidation techniques, which involve high local temperature gradients.

The case study conducted on the alumina powder SPS demonstrates the correlation between the modeling and experimental data. It is noted that this study considers only one of many possible mechanisms of the consolidation enhancement during SPS. Further efforts on the modeling of field‐assisted powder processing are necessary.
PVA‐Assisted Hydrothermal Synthesis of SrTiO3 Nanoparticles with Enhanced Photocatalytic Activity for Degradation of RhB
Authors: Wei Xiao , Xu Gang , Ren Zhaohui , Xu Chunxiao , Shen Ge , Han Gaorong
Published: October 2008

Strontium titanate (SrTiO3) nanoparticles with different particle sizes have been synthesized successfully via a hydrothermal route with the help of polyvinyl alcohol (PVA). The as‐synthesized SrTiO3 nanoparticles were characterized by X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, and scanning electron microscopy. It was found that the particle size and the Sr/Ti molar ratio of the as‐synthesized samples decreased with increasing PVA concentration, accompanied by an increase in the specific surface area. When the PVA concentration was no <1.6 g/L, the Sr/Ti molar ratios of the as‐synthesized samples were <1, indicating that a strontium vacancy (VSr) formed. Their photocatalytic activities were investigated through the degradation of rhodamine B (RhB) under exposure to ultraviolet (UV) radiation (λ=200–400 nm). The results indicated that the photocatalytic activities of the PVA‐assisted hydrothermally synthesized nanocrystalline SrTiO3 powders were higher than that of the sample prepared without PVA. The highest photocatalytic activity was obtained for the sample prepared with an intermediate PVA concentration, arising from the combined effect of the particle size, specific surface area, VSr formation, and the adsorption capacity.
Effects of Alkalinity on the Hydrothermal Synthesis of Lead Titanate Nanotube Arrays
Authors: Yang Yang , Wang Xiaohui , Sun Changku , Yao Guofeng , Li Longtu
Published: October 2008

The alkalinity of hydrothermal solution was proved to have significant effects on the formation of lead titanate nanotube arrays. Using anodic TiO2 nanotube arrays as templates, lead titanate (PbTiO3) nanotube arrays were obtained by in situ hydrothermal synthesis in an alkali‐free solution. The addition of KOH in hydrothermal solutions induced a dissolution–precipitation process, which resulted in the formation of cubic PbTiO3 particles instead of nanotubes. Compared with bulks, the nanotubular structure in PbTiO3 nanotube arrays is responsible for the differences in the Raman spectra for different specimens.
A New Synthesis Method for Producing Si3N4 Whiskers by Heat Treating Porous Si Objects
Authors: Hanjun Hu , Wan‐cheng Zhou , Fa Luo , Dong‐Mei Zhu , Jie Xu
Published: October 2008

Silicon nitride whiskers were successfully synthesized in a porous silicon nitride body in an atmosphere of nitrogen and hydrogen gas flow by reaction bonding. Porous silicon nitride bodies, which contained 0.8 mm diameter spherical macropores and had a porosity of over 90%, were prepared by adding pore‐forming agent grains. The phase of silicon nitride whiskers was mainly α‐Si3N4, including a few β‐Si3N4 and Si2N2O phases. The diameter of the whiskers was about 0.1∼1 μm and the length was higher than 10 μm. More and longer whiskers were formed on the surface of the macropores. The silicon nitride whiskers were grown using the mechanism of chemical vapor deposition.
Photoluminescence Enhancement of Y3Al5O12:Ce Nanoparticles Using HMDS
Authors: Nien Yung‐Tang , Chen Kun‐Ming , Chen In‐Gann , Lin Tai‐Yuan
Published: October 2008

Coprecipitated Y3Al5O12:Ce (YAG:Ce) nanoparticles, treated with hexamethyldisilazane (HMDS) at 150°C for 1 h in an autoclave and then fired at 980°C, showed an enhanced photoluminescence (PL) intensity compared with pure YAG:Ce without any HMDS treatment. X‐ray diffraction analysis revealed a shift of the (420) peak to a higher angle with more HMDS addition, indicating the decreasing lattice parameter caused by the substitution of Al3+ sites with Si4+ ions in the YAG host. Transmission electron micrographs showed a smaller size and more dispersal of YAG:Ce nanoparticles with more HMDS addition, which was caused by OH‐scavenging methyl siloxyl groups. Diffuse reflectivity showed identical absorption behavior for pure and HMDS‐treated YAG:Ce, suggesting the same amount of Ce3+ activators in the YAG host. Therefore, the enhancement of the PL intensity of HMDS‐treated YAG:Ce was supposed to be a result of an increasing diffusion and a homogeneous distribution of Ce3+ activators in YAG, due to the smaller Si4+ ions and the formation of Al3+ vacancies, based on the longer decay time measured.
MicroRNAs in embryonic stem cells and early embryonic development
Authors: Laurent Louise C.
Published: October 2008

Introduction

miRNAs in early embryogenesis

miRNAs in embryonic stem cells

Roles of specific miRNAs in early embryogenesis

Roles of specific miRNAs in embryonic stem cells

miRNAs with common seed sequences

Conclusion

MicroRNAs (miRNAs) are involved in the regulation of a broad range of biological processes. There is an extensive literature on the roles of miRNAs in metazoan development, from early embryogenesis to lineage commitment, and formation and maturation of cellular subtypes and complex tissues. This review will present the evidence that miRNAs are essential for the earliest stages of metazoan development, including establishment and maintenance of the pluripotent embryonic stem cells (ESCs) from which all foetal tissues arise. We will also discuss specific miRNAs that have been associated with early embryogenesis and pluripotency. Finally, we will point out evidence showing that there is strong and highly redundant miRNA regulation of a common set of target genes in the early stages of embryonic development and in ESCs.
Death receptors as targets for anti‐cancer therapy
Authors: Papenfuss Kerstin , Cordier Stefanie M. , Walczak Henning
Published: October 2008

Introduction

Death receptor signalling

TNF‐R1 signalling

CD95 signalling

TRAIL‐R signalling

Targeting death receptors in cancer therapy

Targeting TNF‐R1

Targeting CD95

TRAIL as a target for anti‐cancer therapy

Future perspectives

Human tumour cells are characterized by their ability to avoid the normal regulatory mechanisms of cell growth, division and death. The classical chemotherapy aims to kill tumour cells by causing DNA damage‐induced apoptosis. However, as many tumour cells posses mutations in intracellular apoptosis‐sensing molecules like p53, they are not capable of inducing apoptosis on their own and are therefore resistant to chemotherapy. With the discovery of the death receptors the opportunity arose to directly trigger apoptosis from the outside of tumour cells, thereby circumventing chemotherapeutic resistance. Death receptors belong to the tumour necrosis factor receptor superfamily, with tumour necrosis factor (TNF) receptor‐1, CD95 and TNF‐related apoptosis‐inducing ligand‐R1 and ‐R2 being the most prominent members. This review covers the current knowledge about these four death receptors, summarizes pre‐clinical approaches engaging these death receptors in anti‐cancer therapy and also gives an overview about their application in clinical trials conducted to date.
HER‐2 overexpression/amplification in Barrett’s oesophagus predicts early transition from dysplasia to adenocarcinoma: a clinico‐pathologic study
Authors: Rossi Elisa , Grisanti Salvatore , Villanacci Vincenzo , Casa Domenico Della , Cengia Paolo , Missale Guido , Minelli Luigi , Buglione Michela , Cestari Renzo , Bassotti Gabrio
Published: October 2008

Barrett’s oesophagus (BO) is the primary precursor lesion for oesophageal adenocarcinoma (ADC). The natural history of metaplasia‐dysplasia‐carcinoma sequence remains largely unknown. HER2/neu oncogene results overexpressed/amplified in preneoplastic lesions and in ADC of the oesophagus and it has been associated with poor prognosis. Our aim was to evaluate the role of HER2 overexpression/amplification in predicting the conversion from precursor lesions to ADC. We retrospectively evaluated by univariate analysis of single variables clinical records and histological specimens of 21 patients with a confirmed diagnosis of BO and/or oesophageal dysplasia. Clinical variables included age, gender, alcohol and smoking intake, presence of symptoms (pyrosis, disphagia) and endoscopic features (length). HER2 status was studied by immunohistochemistry and fluorescence in situ hybridization (FISH) on paraffin‐embedded tissue. The end‐points were the occurrence of progression and the time‐to‐progression (TTP) from the initial histologic lesion to the worst pathological pattern. Median age at diagnosis was 63 years (range 37–84). BO median length was 4.5 cm. Progression occurred in 11 of 21 patients and median TTP was 24 months. HER2 was overexpressed/amplified in 8 of 21 (38%) patients. HER2 overexpression/ amplification and the presence of dysplasia were statistically associated with progression (P= 0.038). This study provides evidence for a possible role of HER2 in the transition from dysplasia to ADC of the oesophagus. This fact could help in identifying patients at high risk of malignant transformation.
Immunohistochemical detection of polyductin and co‐localization with liver progenitor cell markers during normal and abnormal development of the intrahepatic biliary system and in adult hepatobiliary carcinomas
Authors: Dorn Livia , Menezes Luís F. , Mikuz Gregor , Otto Herwart F. , Onuchic Luiz F. , Sergi Consolato
Published: October 2008

The longest open reading frame of PKHD1 (polycystic kidney and hepatic disease 1), the autosomal recessive polycystic kidney disease (ARPKD) gene, encodes a single‐pass, integral membrane protein named polyductin or fibrocystin. A fusion protein comprising its intracellular C‐terminus, FP2, was previously used to raise a polyclonal antiserum shown to detect polyductin in several human tissues, including liver. In the current study, we aimed to investigate by immunohistochemistry the detailed polyductin localization pattern in normal (ductal plate [DP], remodelling ductal plate [RDP], remodelled bile ducts) and abnormal development of the primitive intrahepatic biliary system, known as ductal plate malformation (DPM). This work also included the characterization of polyductin expression profile in various histological forms of neonatal and infantile cholestasis, and in cholangiocellular carcinoma (CCC) and hepatocellular carcinoma (HCC). We detected polyductin expression in the intrahepatic biliary system during the DP and the RDP stages as well as in DPM. No specific staining was found at the stage of remodelled bile ducts. Polyductin was also detected in liver biopsies with neonatal cholestasis, including mainly biliary atresia and neonatal hepatitis with ductular reaction as well as congenital hepatic fibrosis. In addition, polyductin was present in CCC, whereas it was absent in HCC. Polyductin was also co‐localized in some DP cells together with oval stem cell markers. These results represent the first systematic study of polyductin expression in human pathologies associated with abnormal development of intrahepatic biliary tree, and support the following conclusions: (i) polyductin expression mirrors developmental properties of the primitive intrahepatic biliary system; (ii) polyductin is re‐expressed in pathological conditions associated with DPM and (iii) polyductin might be a potential marker to distinguish CCC from HCC.
Cutaneous epithelioid angiosarcoma: a neoplasm with potential pitfalls in diagnosis
Authors: Mobini Narciss
Published: October 2008

Angiosarcoma (AS) is a rare neoplasm. Cutaneous AS is the most common form of AS. The epithelioid variant of the disease, however, is a rare entity. This subset can histologically mimic non‐vascular neoplasms and impose serious challenges in reaching the correct diagnosis. We present five patients with cutaneous epithelioid angiosarcoma (EAS); in none, the clinical diagnosis included a vascular lesion. Three patients had history of breast conservation surgery with/without radiation therapy. Other patients had no previous radiation, and there was no lymphedema in any of the cases. The histopathological examination of the biopsy specimens by hematoxylin and eosin method was not suggestive of a malignant vascular neoplasm initially and the differential diagnoses included carcinoma, malignant melanoma and atypical lymphoid infiltrate. Only after performing immunohistochemical studies that included vascular markers, a definitive diagnosis was possible. Some cases showed unusual histopathological features. Cutaneous EAS is a rare variant of cutaneous AS that can mimic a variety of more common, non‐vascular neoplasms, creating a major pitfall in the diagnosis. A careful and thorough histopathological examination and a high index of suspicion, along with appropriate immunohistochemical evaluation, can help reach a correct diagnosis and provide optimal patient care.
Acantholytic anaplastic Paget’s disease
Authors: Mobini Narciss
Published: October 2008

Classic Paget’s disease (PD) can be diagnosed relatively easily by histopathologic examination. ‘Anaplastic’ variant of this disease is a less‐recognized subset that may pose as a diagnostic challenge and pitfall. We describe two cases who presented with scaly erythematous plaques on their nipple/areola. In the first patient, there was no palpable mass and imaging studies were negative. The second case presented with a lesion 5 years after a lumpectomy. Initial shave biopsies revealed histopathologic changes indistinguishable from Bowen’s disease with no readily identifiable classic Paget’s cells, associated with prominent superficial acantholysis. The neoplastic cells were negative for mucin, GCDFP‐15, negative/minimally positive for CEA and strongly positive for CK7 markers. A high‐grade ductal carcinoma in situ in the underlying breast was ultimately found in both cases. Anaplastic PD is a rare variant of this disease that histologically mimics Bowen’s disease with an associated prominent superficial acantholysis. There is mucin, CEA and GCDFP‐15 negativity with positive CK7 reaction. A high index of suspicion along with a complete immunohistochemical panel should be considered in evaluating any Bowenoid neoplasm of the breast skin, particularly in superficial skin shave biopsies along with negative imaging studies and no palpable mass clinically.
Subclassification of desmoplastic melanoma: pure and mixed variants have significantly different capacities for lymph node metastasis
Authors: George Evan , McClain Susannah E. , Slingluff Craig L. , Polissar Nayak L. , Patterson James W.
Published: October 2008

Background:  There is disagreement about the behavior and optimal management of desmoplastic melanoma (DM), particularly regarding the incidence of lymph node (LN) involvement. Recently, investigators have noted the frequently heterogenous histologic composition of DM and have found significant differences between pure desmoplastic melanoma (PDM) (≥90% comprised of histologically typical DM) and mixed desmoplastic melanoma (MDM) [≥10% DM and >10% conventional melanoma (CM)].

Method:  We reviewed 87 cases of DM comparing the histologic and clinical features of PDM (n = 44) to MDM (n = 43).

Results:  At surgical staging, there were LN metastases in 5 of 23 (22%) MDM patients, whereas all 17 PDM patients had negative LN biopsies (0%) (p = 0.04). PDM was less often clinically pigmented (36% vs. 67%) and had a lower mean mitotic index (1.3 vs. 3.0).

Conclusions:  There are differences between PDM and MDM, the most important of which is the incidence of LN involvement. Our findings support the clinical utility of classifying DM into pure and mixed subtypes because the negligible rate of nodal involvement in PDM does not support the routine performance of sentinel LN biopsy in this subgroup of melanoma patients. In contrast, the incidence of LN involvement in MDM is comparable to that of CM.
Identification of a novel Bacillus species isolated from Calculus Bovis
Authors: WAN Tien‐Chun , CHENG Fu‐Yuan , LIU Yu‐Tse , WANG Chao‐Ming , SHYU Ching‐Lin , CHEN Chih‐Ming , LIN Liang‐Chuan , SAKATA Ryoichi
Published: October 2008

A novel Bacillus species of Calculus Bovis (cow gallstone) was isolated and identified in this study. Morphological features, bacterial fatty acid analysis using a microbial identification system, carbon source utilization profiles using Biolog system and 16S rDNA sequencing were employed to identify the isolated bacterium. This isolated bacterium was observed to be Gram‐negative, aerobic growing, rod‐shaped and short chain. The results of bacterial fatty acid analysis and physiological characteristics were not matched to the database. The main fatty acids found in the bacterium were 65.96% branched chain saturated fatty acids (iso C11:0, anteiso C11:0 and iso C13:0∼anteiso C19:0). The bacterium oxidized 35 carbon sources and weakly responded with 49 of the 95 different carbon sources analyzed with the Biolog identification system. Based on 16S rDNA sequence analysis, this bacterium was classified as a novel Bacillus species.
Structural determination of the oligosaccharides in the milk of a giant anteater (Myrmecophaga tridatyla)
Authors: URASHIMA Tadasu , KOMODA Miki , ASAKUMA Sadaki , UEMURA Yusuke , FUKUDA Kenji , SAITO Tadao , OFTEDAL Olav T.
Published: October 2008

There appears to be strong evidence supporting four major clades of placental mammals: (i) Afrotheria; (ii) Xenarthea; (iii) Euarchontoglires; and (iv) Laurasiathera. This is the first study in which the carbohydrates have been analyzed in the milks of Xenarthea. Our aim was to clarify whether the saccharides of giant anteater milk resemble those of other eutherian species, especially of the Asian elephant, which is one of the Afrotherea. We found that lactose is a dominant saccharide in this milk, as it is in that of most eutherians, and that the milk contains smaller amounts of oligosaccharides, whose structures were determined as Gal(α1‐3)Gal(β1‐4)Glc (isoglobotriose), Neu5Ac(α2‐6)Gal(β1‐4)Glc (6'‐N‐acetylneuraminyllactose), Neu5Gc(α2‐6)Gal(β1‐4)Glc (6'‐N‐glycolylneuraminyllactose), Neu5Ac(α2‐6)Gal(β1‐4)GlcNAc(β1‐3)Gal(β1‐4)Glc (LST c) and Neu5Gc(α2‐6)Gal(β1‐4)GlcNAc(β1‐3)Gal(β1‐4)Glc. This pattern of milk carbohydrates is rather close to that of the milks of other eutherian species. It is notable that the milk contained oligosaccharides with Neu5Gc residues but no oligosaccharides containing α(2‐3) linked Neu5Ac residues such as Neu5Ac(α2‐3)Gal(β1‐4)Glc.
Environmental impacts of a Japanese dairy farming system using whole‐crop rice silage as evaluated by life cycle assessment
Authors: OGINO Akifumi , ISHIDA Motohiko , ISHIKAWA Tetsuya , IKEGUCHI Atsuo , WAKI Miyoko , YOKOYAMA Hiroshi , TANAKA Yasuo , HIROOKA Hiroyuki
Published: October 2008

The objectives of this study were to assess and compare the environmental impacts of two types of dairy farming systems, one of which makes use of whole‐crop rice silage and the other of which is conventional, using life cycle assessment (LCA). The functional unit was defined as 1 kg of 4% fat‐corrected milk (FCM). The processes associated with the dairy farming life cycle, such as feed production, feed transport, animal management including biological activity of the animal, and waste treatment were included within the system's boundaries. Environmental impacts of the rice silage‐using and conventional dairy farming systems were 987 and 972 g CO2 equivalents for global warming, 6.87 and 7.13 g SO2 equivalents for acidification, 1.19 and 1.23 g PO4 equivalents for eutrophication, and 5.53 and 5.81 MJ for energy consumption, respectively. Our results suggest that the dairy farming system using rice silage in Japan has smaller environmental impacts for acidification, eutrophication, and energy consumption, and a larger impact for global warming compared with conventional farming. Further interpretation integrating these impact categories suggested 1.1% lower environmental impact of the rice silage‐using dairy farming system as a whole.
Quantitative real‐time PCR monitoring of Escherichia coli and Clostridium perfringens with oral administration of Lactobacillus plantarum strain Lq80 to weaning piglets
Authors: TAKAHASHI Shunsuke , YOSHIDA Yoko , NAKANISHI Nobuo , TSUKAHARA Takamitsu , USHIDA Kazunari
Published: October 2008

Levels of fecal or intestinal lactobacilli, Escherichia coli and Clostridium perfringens, and the prevalence of clostridial alpha toxin gene and heat‐stable toxin (ST) gene of enterotoxigenic E. coli (ETEC) were monitored in weaned piglets before (day 0) and during (days 7, 14, and 21) the administration of Lactobacillus plantarum strain Lq80. Lactobacilli were enumerated in a culture‐dependent method. The remainders were determined by quantitative real‐time PCR. In this quantitative real‐time PCR method, the detection limit was proved to be as low as 103 cells/g feces or intestinal contents. Number of lactobacilli increased from day 0 to day 7 (P < 0.05), to day 14 (P < 0.05), and to day 21 (P = 0.07) in the Lq80‐administered group. L. plantarum contributed to as low as 10% of the lactobacillal population in the Lq80‐administered group. The number of E. coli and C. perfringens, and the prevalence of alpha toxin gene in feces or intestinal contents of the Lq80‐administered group decreased, at least in the first week of the postweaning period. Oral administration of L. plantarum strain Lq80 can stimulate the growth of indigenous lactobacilli and decrease ST‐producing ETEC and C. perfringens in the intestine of postweaning piglets.
Methodology for the study of the hypothalamic‐pituitary hormone secretion in cattle
Authors: HASHIZUME Tsutomu , KASUYA Etsuko
Published: October 2008

Studies on the neuroregulatory mechanisms on the secretion of anterior pituitary (AP) hormones in domestic animals are important because nearly all complex physiological and metabolic processes are regulated by the AP hormones. To examine them, this article considers in vivo approaches such as the techniques of intrahypothalamic injection, intracerebroventricular injection, push‐pull perfusion, and microdialysis, which have been employed in our own research group for the study in cattle. Also, in vitro approaches such as bovine AP cell culture and the AP explants superfusion system are described. This article clarifies the potential of neuroendocrine study techniques in cattle.
Nutrient utilization and manure P excretion in growing pigs fed corn‐barley‐soybean based diets supplemented with microbial phytase
Authors: EMIOLA Adewale , AKINREMI Oluwole , SLOMINSKI Bogdan , NYACHOTI C. Martin
Published: October 2008

The effect of high levels of microbial phytase supplementation in diets for growing pigs was studied in a 2‐week performance and nutrient digestibility trial involving 28 growing pigs weighing 16.4 ± 1.06 (mean ± SD) kg. Seven corn‐barley‐soybean meal‐based diets consisting of a positive control (PC) formulated to meet or exceed NRC nutrient requirements; a negative control (NC) with non‐phytate P reduced by 0.1% unit from NRC requirement and fed without or with 500 or 1000 U/kg; a doubled negative control (DNC) with no added inorganic P and fed without or with 2000 or 4000 U/kg. Chromic oxide was added as an indigestible marker and all diets were fed as mash. Pigs fed the PC diet had a higher P digestibility compared with those fed the NC (P < 0.02) and the DNC (P < 0.001) diets. Supplementing the NC diet with pyhtase tended to improve P digestibility (P < 0.10). However, addition of phytase to the DNC diet resulted in linear (P < 0.001) and quadratic (P < 0.03) increases in P digestibility with an overall improvement of 8% and 121% at 4000 phytase U/kg of diet, respectively, compared with the PC and DNC diets. Apparent total tract digestibility of N, OM and DM were higher (P < 0.05) in the PC diet compared with the DNC diet, but not the NC diet (P < 0.10). No effect of phytase addition to NC was observed on Ca, N, DM and OM digestibility. Phytase addition to the DNC diet resulted in a linear increase (P < 0.05) in N, DM and OM digestibility but not Ca. Increasing the levels of phytase supplementation in the NC and the DNC diets linearly decreased fecal P (P < 0.05) content by 45 and 42%, respectively. Adding phytase at 1000 or 4000 U/kg increased P retention (P < 0.05) by 14.3 or 15.6% units, respectively, compared with the PC diet. Urinary P excretion was higher in the group fed the PC diet compared with those fed the NC and DNC diets (P < 0.05). The results of this study show that complete removal of inorganic P from growing pig diets coupled with phytase supplementation improves digestibility and retention of P and N, thus reducing manure P excretion without any negative effect on pig performance.
Effects of herbage intake on goat performance in the mediterranean type natural pastures
Authors: HAKYEMEZ Basri H. , GOKKUS Ahmet , SAVAS Turker , YURTMAN Ismail Y.
Published: October 2008

This study aimed at identifying changes in natural pastures during the grazing season and investigating the effects of these changes on pasture feeding potential for high yielding dairy goats. During the study, 12 dairy goats were grazed on a 1.5 ha natural pasture for three months from April to June in 2003, 2004 and 2005. The goats were fed 0.5 kg/day of concentrate as a supplement during the grazing season. Botanical composition, herbage production and intake, crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of the pasture were determined. Live weight, milk yield, milk dry matter (DM) and fat content of the goats were monitored. The data were analyzed using a linear model, which evaluated the effects of grazing seasons in each year. Based on the three‐year average, 87% of pasture was herbaceous plants and the remaining was shrubs in DM basis with Cistus creticus, Quercus ithaburensis, Pistacia atlantica and Asparagus acutifolius being the major shrub species. The herbage yield in June was significantly lower than in other months in all years (P = 0.001). In all experimental years, the CP content of the pasture decreased but the structural carbohydrates increased as the grazing season proceeded. While live weight was not affected by grazing periods except for 2004 (P = 0.001), milk yield significantly decreased with advancing grazing period (P = 0.001). The results of the present study indicate that natural pasture has a supportive effect in April and May on the milk yield of lactating goats which are in mid‐lactation, and suggested that supplementary feeding is required in consecutive grazing periods.
The effect of Eucommia ulmoides leaf supplementation on the growth performance, blood and meat quality parameters in growing and finishing pigs
Authors: LEE Sung Dae , KIM Hoi Yun , SONG Young Min , JUNG Hyun Jung , JI Sang Yun , JANG Hae Dong , RYU Jae Weon , PARK June Cheol , MOON Hong Kil , KIM In Cheul
Published: October 2008

The aim of the present study was to investigate the effect of Eucommia ulmoides leaf (EUL) supplementation on the growth performance, blood and meat quality parameters in growing and finishing pigs. Ninety gilts (L × LW × D, 20 kg initialBW) were housed 10 per pen in a front‐open building with three replicate pens per treatment. Experimental treatment was started from the beginning of the growing stage (20 ± 3 kg) by supplementing EUL at 0(C), 3(T1) and 5% (T2) to the growing and finishing diet. Pigs were slaughtered by electrical stunning at 105 ± 3 kg live weight. Average daily feed intake (ADFI, kg/day) decreased (P < 0.05) by addition of EUL in growth performance, average daily gain (ADG, kg/day) was lower (P < 0.05) in T1 and T2 than in C. In hematology, leukocytes (WBC, 103/mm3) decreased (P < 0.05) in T1 and T2 than in C. Erythrocytes (RBC, 106/mm3), hemoglobin (HGB, g/dL) and hematocrit (HCT, %) increased (P < 0.05) in T1 and T2 than in C. Platelet (PLT, 103/mm3) was lower (P < 0.05) in T2 than in C and T1. In biochemical composition of serum, total protein (g/dL), r‐GTP (μ/L), total cholesterol (mg/dL) and triglycerides (mg/dL) were lower (P < 0.05) in T1 and T2 than in C. On longissimus dorsi muscle, crude protein was higher (P < 0.05) in T1 than in C. Crude ash was higher (P < 0.05) in T1 and T2 than in C. Yellow to blue color scale (CIE b*) in meat color was higher (P < 0.05) in T2 than in C. CIE b* in back fat color was higher (P < 0.05) in T2 than in the other treatments. In sensory evaluation scores for fresh meat, the values of meat color, fat color, drip loss and marbling were not significantly affected by addition of EUL. In cooked meat, the values of chewiness and overall acceptability were higher (P < 0.05) in T1 and T2 than in C. The results indicate that the addition of EUL affected growth performance, blood parameters and meat quality parameters in growing and finishing pigs.
Effects of GH gene polymorphism and sex on carcass traits and fatty acid compositions in Japanese Black cattle
Authors: ARDIYANTI Astrid , OKI Yoshie , SUDA Yoshihito , SUZUKI Keiichi , CHIKUNI Koichi , OBARA Yoshiaki , KATOH Kazuo
Published: October 2008

To investigate the effects of bovine growth hormone (bGH) gene polymorphism on carcass traits and fatty acid compositions in Japanese Black cattle caused by nucleotide substitution of CTG (allele A)/GTG (allele B) at codon 127 and of ACG (allele A and B)/ATG (allele C) at codon 172 of bGH, GH genotypes of 135 cattle were determined using allele specific‐multiplex polymerase chain reaction (PCR). Allele A gave greater rib thickness and lower melting point of fat (MP) while allele B gave higher C18:1% (P < 0.05). Allele C gave higher C18:1, monounsaturated fatty acid (MUFA), unsaturated fatty acid (USFA) percentages (P < 0.05). It also gave lower saturated fatty acid (SFA) percentages, higher MUFA/SFA and USFA/SFA ratios, and lower MP (P < 0.05). Interactions of sex and GH alleles were analyzed. In heifers, allele A gave higher carcass weight, daily carcass gain, rib eye area, rib thickness, subcutaneous fat thickness, and BMS while allele B gave greater rib eye area and rib thickness (P < 0.05). Allele C gave higher C18:1 (P < 0.01), MUFA (P < 0.01), USFA percentages (P < 0.05) and MUFA/SFA and USFA/SFA ratios (P < 0.01), and lower C16:0 and SFA percentages (P < 0.05) and MP (P < 0.01). GH gene polymorphism affected carcass traits and fatty acid compositions although the effects were more pronounced in heifers.