bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis and Modeling of Depletion‐Mode MOS Transistors
Authors: Kumar Umesh
Published: April 2008

Depletion mode MOSFETs are widely used in MOS—LSI/VLSI circuits as load elements. The main advantages offered by these devices are:

Higher packaging density,

Improved performance,

Reduced power consumption, etc.

Masuhara et. al (1972) developed a model for analysis of this device as an enhancement mode MOSFET. The model was adequate for analysis of lightly‐doped, shallow‐implanted channels. Subsequently, a more rigorous analysis was put forth by HAKEN for larger doping and deep channels. The analysis made by Edward and Marr did not simplify the non‐linear relationship between surface depletion region width and gate voltage. The model also did not account for the transconductance of the device in the three operating regimes.

In this paper, the various models are briefly examined, and an attempt has been made for extraction of various parameters for obtaining the DC characteristics of these devices.
Geometry Induced Localization of Electrons in Quantum Pillars
Authors: Tigelis Ioannis G. , Xanthakis John P.
Published: April 2008

We investigate the energies and wavefunctions of a structure consisting of one small cubic
box centered on top of another larger with a uniform potential inside. This model is a
representation of a quantum pillar on a substrate, a nanostructure with potential device
applications. We find that the eigenstates are localized in one or the other of the boxes. Those
in the large box are very well localized while those in the small are moderately so. Their
energy and localization are studied with respect to the ratio of sides of the two boxes and
compared with the results obtained with the small box closed by all sides.
A Mathematical Formulation for Diamagnetism in Tetrahedrally Bonded Semiconductors
Authors: Grado-Caffaro M. A. , Grado-Caffaro M.
Published: April 2008

An expression for the magnetic susceptibility tensor corresponding to diamagnetic contribution in tetrahedrally bonded semiconductors is derived; this formulation refers to the crystalline state. In addition, a comparison with the amorphous case is outlined.
New Single‐Resistor Controlled Sinusoidal Oscillator Circuit UsingUnity‐Gain Current Followers
Authors: Abuelma′atti Muhammad Taher , Al-Daghreer Hassan
Published: April 2008

A new configuration for realizing current‐follower‐based sinusoidal oscillator is presented.
The circuit uses two unity‐gain current followers, three capacitors, and three resistors, and
enjoys independent control of its frequency and condition of oscillation. Experimental results
are included.
Current‐Mode Universal Filter Using FTFNs
Authors: Abuelma′atti Muhammad Taher , Al-Zaher Husain Abdullah
Published: April 2008

A new current‐mode universal filter is presented. The proposed filter uses three four‐terminal
floating nullors (FTFNs), three grounded capacitors, and four grounded resistors. The proposed
filter has three inputs and one output and can realize lowpass, highpass, bandpass, notch, and
allpass transfer functions without changing the circuit topology. The proposed filter enjoys low
active and passive sensitivities and independent control of the parameters ω0 and ω0/Q0 using grounded elements.
N‐Channel InGaAs Quantum Well Lasing Thyristor (QWLT) Prepared by Molecular Beam Epitaxy
Authors: Chen H. C.
Published: April 2008

N‐channel lnGaAs quantum well lasing thyristors (QWLT) based on regenerative loop of
potential barrier lowering resulted from the forward biased pn junction is demonstrated in a
AlGaAs/GaAs double heterostructure. Excellent electrical switching characteristics with a
high voltage control efficiency ηv( = Vs/VH) of 6.7 have been obtained when the device is
operated in the dark. Typical OFF‐ and ON‐state resistances are 150KΩ and 10Ω respectively.
A lasing threshold current density, front slope efficiency, and external differential
quantum efficiency measured in as‐cleaved device are 183A/cm2, 0.4mW/mA, and 31%,
respectively. The peak emission wavelength is centered at about 980nm.
Diode Parameter Determination Applied to LDD‐MOSFETs for DeviceCharacterization
Authors: De La Bardonnie M. , Mialhe P. , Bendada E. , Blampain E. , Hoffmann A. , Charles J.-P.
Published: April 2008

The electrical properties of the drain‐substrate diode of MOSFETs are shown to be
related to the device geometrical structure. The two dimensional analysis takes into
account the edge effects of the length and width of the gate. Intrinsic parameters are
extracted from current‐voltage characteristics and obtained dependent on these
dimensions.
A Programmable Reference‐Voltage Source
Authors: Abuelma′atti Muhammad Taher , Al-Shahrani Sa′ad Muhammad
Published: April 2008

A simple circuit for realizing a current(voltage)‐controlled reference voltage is presented.
The feasibility of obtaining a temperature‐insensitive reference voltage is explored. SPICE
simulation results are included.
Applications of Nanoscale Materials in the Fields of Electrochemistry and Photoelectrochemistry
Authors: Campet G. , Deshayes A. , Frison J. C. , Treuil N. , Portier J.
Published: April 2008

We have illustrated the important role played by the nanoscale materials in three‐up‐to‐date
energy topics.

1/The solar‐to‐electrical energy conversion in photoelectrochemical cells: we have shown
two favorable situations for which photoelectrochemical cells using porous nanocrystalline
films have high efficiencies.

2/The electrical energy storage in rechargeable rocking‐chair lithium batteries: these systems,
which use nanocrystalline materials, might be the next generation of rechargeable batteries
showing higher capacity, cyclability, and safety than conventional lithium ion batteries.

3/The energy saving with efficient electrochromic windows using nanocrystalline materials.
Optimization of the Synthesis Procedure of LiMn2O4 Electrodes for Efficient Rechargeable Lithium Cells: Influence of the Crystallite Size and Surface Defects on the Electrochemical Performances of 3 V Li1+xMn2O4 and 4V Li1-xMn2O4 Electrodes
Authors: Treuil N. , Deshayes A. , Frison J. C. , Grenier J. C. , Rabardel L. , Sellier E. , Portier J. , Campet G.
Published: April 2008

Various LiMn2O4 electrode materials, having different crystallite sizes ranging from ∼50Å to ∼500Å, have been investigated either in 3V or in 4V Li batteries. In agreement with our ≪electrochemical model≫, we have shown that nanocrystalline samples have
much higher capacity, and cyclability than their microcrystalline homologue in the 3 V domain uniquely. A reverse trend is observed in the 4 V range, still in agreement with the model.
Development of Electrochromic Devices Working with Hydrophobic Lithium Electrolyte
Authors: Park Nam-Gyu , Poquet Armel , Campet Guy , Portier Josik , Choy Jin-Ho , Kim Young-Il , Camino D. , Salardenne J.
Published: April 2008

This manuscript report on a new lithium electrolyte, allowing the
manufacturing of electrochemical systems, such as electrochromic
devices, in ambient atmosphere. It is based on lithium
bis‐trifluoromethane sulfonimide dissolved in the following
hydrophobic salt, which was first prepared by M. Grätzel et
al.: 1‐ethyl. 3‐methyllimidazolium bis‐trifluoromethane
sulfonimide. We have also successfully tested the compatibility of
this electrolyte with WO3 and TiO2‐CeO2 films acting respectively
as efficient electrochromic electrode and counter electrode for
smart‐window working with Li+ions.
Versatile Active Biquad Using FTFNs
Authors: Abuelma′atti Muhammad Taher , Al-zaher Husain Abdullah
Published: April 2008

A universal active biquad using the four‐terminal floating nullors
(FTFNs) is presented. The propsed circuit uses two FTFNs,
three capacitors and two resistors. The proposed circuit has three
input voltages and can simultaneously provide a high‐impedance
output current and/or an output voltage. Without changing the
circuit topology, the output voltage can realise lowpass,
highpass, bandpass, notch and allpass transfer functions and the
output current can realise bandpass and highpass transfer
functions. The proposed circuit enjoys low active and passive
sensitivities and independent control of the parameters ωo and ω0/Q0.
An Algorithm to Develop Lumped Model for Gunn‐Diode Dynamics
Authors: Kumar Umesh
Published: April 2008

A nonlinear lumped model can be developed for Gunn‐Diodes to describe the diffusion
effects as the domain travels from cathode to anode of a Gunn‐Diode. The model
describes the domain extinction and nucleation phenomena. It allows the user to specify
arbitrary nonlinear drift velocity V(E) and nonlinear diffusion D(E).

The model simulates arbitrary Gunn‐Diode circuits operating in any matured high
field domain or in the LSA mode.

Here we have constructed an algorithm to lead to development of this model
On the Total Electronic Density of States of Disordered Solids
Authors: Grado-Caffaro M. A. , Grado-Caffaro M.
Published: April 2008

The concept of total electronic density of states calculated for small clusters in
amorphous solids is presented in a new way by using a mathematical formulation based
upon matrix calculus. Furthermore, the associated Green′s function is discussed in a
special form. Our results can be used to study amorphous solids as a‐Ge and a‐Si.
A Brief Study to Clarify Some Aspects Related to VibrationalDensity of States for the Far Infrared Range in AmorphousSemiconductors
Authors: Grado-Caffaro M. A. , Grado-Caffaro M.
Published: April 2008

Phonon density of states of amorphous semiconductors for the far‐infrared range is
examined analytically. On the basis of this formulation, optical absorption corresponding
to structural disorder is evaluated and discussed at the far‐infrared range for a‐Ge
and a‐Si.
DC and AC Characteristics of GaAs/InGaAs/AIGaAS Real Space Transfer Transistors
Authors: Chen H. C.
Published: April 2008

DC and AC performances of a GaAs/InGaAs/AIGaAs negative resistance field‐effect transistor
(NERFET) are demonstrated by molecular beam epitaxy (MBE) for the first time. The
negative differential resistance (NDR) resulted from the observation of the hot electron real
space transfer effect in InGaAs channel. By Hall measurements, the structure shows carrier
mobility as high as 4300 (13500) cm2/v‐s at 300 (77)K, which is suitable for high frequency
operation. For DC performance, the largest peak‐to‐valley current ratio of the device is about
5 at room temperature. For AC performance, S‐parameter measurements of high frequency
and microwave characteristics indicate a projected maximum frequency of oscillation of
fmax⁡ = 2.7GHz and a current gain cutoff frequency (fT) occurs at 1.8GHz.
Versatile Active Biquad Based on Dual‐Output Second‐GenerationCurrent Conveyors
Authors: Abuelma′atti M. T. , Alzaher H. A.
Published: April 2008

A universal active biquad based on the dual‐output second‐generation current‐conveyor
(CCII±) is presented. The circuit uses only six CCII± and can, simultaneously, support
three mixed‐mode transfer functions and five current‐mode transfer functions. The
circuit uses grounded resistors and capacitors and enjoys independent grounded‐element
control of the filter parameters.
Reliability and Availability Analysis of Some Systems with Common‐Cause Failures Using SPICE Circuit Simulation Program
Authors: Abuelma′atti Muhammad Taher , Qamber Isa Salman
Published: April 2008

The effectiveness of SPICE circuit simulation program in calculating probabilities, reliability, steady‐state availability and mean‐time to failure of repairable systems described by Markov models is demonstrated. Two examples are presented. The first example is a warm standby system with common‐cause failures and human errors. The second example is a non‐identical unit parallel system with common‐cause failures. In both cases recourse to numerical solution is inevitable to obtain the Laplace transforms of the probabilities. Results obtained using SPICE are compared with previously published results obtained using the Laplace transform method. Full SPICE listings are included.
Three‐Dimensional Modelling and Simulation Theory of Field Effect Devices
Authors: Doja M. N. , Moinuddin  , Kumar Umesh
Published: April 2008

In recent years, semiconductor manufacturers have been able to steadily reduce the physical area required by devices, thus allowing an increasing number of circuit functions on a single chip. Smaller semiconductor devices require more detailed and accurate analysis because minor errors can degrade their performance substantially.

A new, completely numerical three‐dimensional model of a MOSFET allows a unified treatment of small devices. Preliminary results show that device size effects the surface potential and threshold voltage. Classical theory does not predict these effects. Although the model currently converges slowly, it can still be useful in analysing new small geometry devices.
Using Spice Circuit Simulation Program in Reliability Analysis ofRedundant Systems with Non‐Repairable Units and Common‐CauseFailures
Authors: Abuelma′atti Muhammad Taher , Qamber Isa Salman
Published: April 2008

The effectiveness of Simulation Program with Integrated Circuit Emphasis (SPICE) in calculating probabilities, reliability, steady‐state availability and mean‐time to failure of redundant systems with non‐repairable units and common‐cause failures described by Markov models is demonstrated. General equations and procedure for constructing the equivalent circuit for N parallel units are presented. Results obtained, for N=1,2,3, using SPICE are compared with previously published results obtained using the Laplace transform method. Full SPICE listings are included.
Imaging Bone and Soft Tissue Tumors with the Proliferation Marker [18F]Fluorodeoxythymidine
Authors: Buck Andreas K. , Herrmann Ken , Büschenfelde Christian Meyer zum , Juweid Malik E. , Bischoff Mark , Glatting Gerhard , Weirich Gregor , Möller Peter , Wester Hans-Jürgen , Scheidhauer Klemens , Dechow Tobias , Peschel Christian , Schwaiger Markus , Reske Sven N.
Published: April 2008

Purpose: We have determined the ability of positron emission tomography (PET) with the thymidine analogue 3`-deoxy-3′[18F]fluorothymidine (FLT) to detect manifestation sites of bone and soft tissue tumors, to assess tumor grading, and to differentiate malignant from benign tumors.

Materials and Methods: In this prospective bicenter trial, FLT-PET was done in 22 patients with established or suspected soft or bone tissue lesions. Routine diagnostic procedures included incisional biopsy, magnetic resonance imaging, and/or contrast-enhanced spiral computed tomography in all patients and [18F]fluorodeoxyglucose (FDG)-PET in 15 patients. Forty-five to 60 minutes after i.v. injection of 350 to 425 MBq FLT, emission and transmission scanning was done. Tracer uptake in the tumor was evaluated semiquantitatively by calculation of mean and maximum standardized uptake values (FLT-SUV) and compared with respective values of FDG. Results were correlated to histopathology and tumor grading.

Results: FLT-PET detected all malignant bone or soft tissue tumors (17 of 17). Mean FLT-SUV in benign lesions was 0.7 (range, 0.3-1.3), and 1.3 in low-grade sarcoma (grade 1; range, 1.0-1.6), 4.1 (range, 2.2-6.0; P = 0.002) and 6.1 (range, 2.5-8.3; P = 0.001) in grade 2 and grade 3 tumors, respectively. FLT but not FDG uptake correlated significantly with tumor grading (r = 0.71 versus r = 0.01), and a cutoff value of 2.0 for FLT-SUV discriminated between low- and high-grade tumors.

Conclusion: In this clinical study, the proliferation marker FLT was suitable for imaging malignant bone or soft tissue tumors. FLT but not FDG uptake correlated significantly with the tumor grade, suggesting FLT as superior PET tracer for noninvasive grading of sarcomas.
Loss of Heterozygosity at the BRCA2 Locus Detected by Multiplex Ligation-Dependent Probe Amplification is Common in Prostate Cancers from Men with a Germline BRCA2 Mutation
Authors: Willems Amber J. , Dawson Sarah-Jane , Samaratunga Hema , De Luca Alessandro , Antill Yoland C. , Hopper John L. , Thorne Heather J. ,   and kConFab Investigators
Published: April 2008

Purpose: Prostate cancer risk is increased for men carrying a pathogenic germline mutation in BRCA2, and perhaps BRCA1. Our primary aim was to test for loss of heterozygosity (LOH) at the locus of the mutation in prostate cancers from men who a carry pathogenic germline mutation in BRCA1 or BRCA2, and to assess clinical and pathologic features of these tumors.

Experimental Design: From 1,243 kConFab families: (a) 215 families carried a pathogenic BRCA1 mutation, whereas 188 families carried a pathogenic BRCA2 mutation; (b) of the 158 men diagnosed with prostate cancer (from 137 families), 8 were confirmed to carry the family-specific BRCA1 mutation, whereas 20 were confirmed to carry the family-specific BRCA2 mutation; and (c) 10 cases were eliminated from analysis because no archival material was available. The final cohort comprised 4 and 14 men with a BRCA1 and BRCA2 mutation, respectively. We examined LOH at the BRCA1 and BRCA2 genes using multiplex ligation-dependent probe amplification of DNA from microdissected tumor.

Results: LOH at BRCA2 was observed in 10 of 14 tumors from BRCA2 mutation carriers (71%), whereas no LOH at BRCA1 was observed in four tumors from BRCA1 mutation carriers (P = 0.02). Under the assumption that LOH occurs only because the cancer was caused by the germline mutation, carriers of BRCA2 mutations are at 3.5-fold (95% confidence interval, 1.8-12) increased risk of prostate cancer. A high Gleason was the only distinct clinical feature.

Conclusions: These observations are consistent with the idea that BRCA2, but not BRCA1, is a tumor suppressor of prostate cancer.
MRP7/ABCC10expression is a predictive biomarker for the resistance to paclitaxel in non-small cell lung cancer
Authors: Oguri Tetsuya , Ozasa Hiroaki , Uemura Takehiro , Bessho Yuji , Miyazaki Mikinori , Maeno Ken , Maeda Hiroyoshi , Sato Shigeki , Ueda Ryuzo
Published: April 2008

We used the paclitaxel-resistant human small cell lung cancer subline PC-6/TAX1-1, selected from PC-6 cells by paclitaxel, to test whether MRP7/ABCC10 (ABCC10) confers paclitaxel resistance. We found that gene expression of both ABCB1/MDR1 (ABCB1) and ABCC10 was higher in PC-6/TAX1-1 cells than in PC-6 cells. The expression levels of ABCC10 showed a significant inverse correlation with paclitaxel sensitivity (r = 0.574; P < 0.05) in 17 non-small cell lung cancer (NSCLC) cells unlike the expression levels of ABCB1. Pretreatment with the ABCC10 inhibitor sulfinpyrazone altered the sensitivity to paclitaxel in ABCC10-expressing NSCLC cells, concomitant with increased intracellular paclitaxel accumulation. These findings suggest that expression of the ABCC10 gene is induced by paclitaxel and that ABCC10 confers paclitaxel resistance by enhancing the efflux for paclitaxel. To confirm this hypothesis, we tested the effect on paclitaxel cytotoxicity of decreasing the expression of ABCC10 by small interfering RNA and found that this enhanced paclitaxel cytotoxicity in NCI-H23 cells concomitant with increased intracellular paclitaxel accumulation. These data indicate that ABCC10 may be one of the biomarkers for paclitaxel resistance in NSCLC. [Mol Cancer Ther 2008;7(5):1150–5]
Medullary thyroid cancer: targeting the RET kinase pathway with sorafenib/tipifarnib
Authors: Hong David , Ye Lei , Gagel Robert , Chintala Lakshmi , El Naggar Adel K. , Wright John , Kurzrock Razelle
Published: April 2008

Medullary thyroid carcinoma (MTC) is an uncommon malignancy of hereditary and sporadic presentation. Mutations in the RET proto-oncogene are involved in the pathogenesis of familial MTC and >50% of the sporadic cases. Currently, there is no effective treatment for recurrent or metastatic MTC. We report here a rapid response to a sorafenib (RET and RAF kinase and vascular endothelial growth factor receptor inhibitor)–based regimen in a patient with sporadic MTC who had advanced, progressive disease and a novel RET kinase aberration at exon 11 shown in tumor tissue. [Mol Cancer Ther 2008;7(5):1001–6]
Equine clinical cytogenetics: the past and future
Authors: Lear T.L. , Bailey E.
Published: April 2008

Cytogenetic analyses of horses have benefited the horse industry by identifying chromosomal aberrations causing congenital abnormalities, embryonic loss and infertility. Technical advances in cytogenetics enabled the identification of chromosome specific aberrations. More recently, advances in genomic tools have been used to more precisely define chromosome abnormalities. In this report we review the history of equine clinical cytogenetics, identify historical landmarks for equine clinical cytogenetics, discuss how the current use of genomic tools has benefited this area, and how future genomics tools may enhance clinical cytogenetic studies in the horse.
Cytogenetics of wild and captive bred non-domestic animals
Authors: Rubes J. , Musilova P. , Mastromonaco G.F.
Published: April 2008

Cytogenetics of wild and captive bred non-domestic animals provides us with valuable information that can be implemented in wildlife management and species conservation strategies. In this review, we summarized the data published to date describing a range of chromosome abnormalities observed in non-domestic animals and their effect on phenotype. Two important factors that can potentially have drastic effects on captive breeding programs are discussed: presence of classic chromosome abnormalities, spontaneously-occurring and inherited, and intraspecific variations in chromosome number. Short-term consequences, primarily reduced reproductive efficiency, and long-term consequences, such as changes in population dynamics, are examined.
Detection of translocation rob(1;29) in bull sperm using a specific DNA probe
Authors: Vozdova M. , Kubickova S. , Cernohorska H. , Rubes J.
Published: April 2008

The Robertsonian translocation rob(1;29), connected with reduced fertility, is widespread in different cattle breeds all over the world. After laser microdissection, DOP-PCR, cloning and sequencing, a highly sensitive translocation-specific DNA probe, suitable for detection of rob(1;29) in cattle metaphase and interphase cells, including spermatozoa was designed. Sperm samples of five heterozygous translocation carriers were analyzed using this probe and a control probe for chromosome 6. One thousand decondensed spermatozoa from each bull were scored. Signals of the translocation-specific probe were detected in 48.8, 50.9, 50.1, 51.8, and 54.8% of spermatozoa, respectively. In contrast, semen samples from five chromosomally normal bulls showed only signals of the control probe for chromosome 6. Semen from a chimeric (XX/XY) bull, showing 57.5% of 59,XX,rob(1;29) and 42.5% of 60,XY cells in cultured peripheral lymphocytes, was also examined using this probe. No sperm head with signal of the translocation-specific probe was observed among 1,000 spermatozoa analyzed in this bull, demonstrating that female cells do not pass through the process of spermatogenesis.
Meiotic studies in an azoospermic boar carrying a Y;14 translocation
Authors: Pinton A. , Raymond Letron I. , Berland H.M. , Bonnet N. , Calgaro A. , Garnier-Bonnet A. , Yerle M. , Ducos A.
Published: April 2008

A reciprocal translocation between the q arm of the Y chromosome and the q arm of chromosome 14 was identified in a young, phenotypically normal boar presenting azoospermia. Testicular biopsies were analyzed by classical histological and immunolocalization techniques, and by fluorescence in situ hybridization. Meiotic pairing analysis of 85 pachytene spreads showed the presence of an open structure corresponding to a quadrivalent formed by chromosomes 14, X, and the derivative chromosomes 14 and Y in 84.7% of the cases. In the remaining cases (15.3%), a ‘trivalent plus univalent’ configuration was observed. Immunolocalization of γH2AX revealed the presence of this modified histone in the chromatin domains of unsynapsed segments (centromeric region of chromosome 14) and spreading of the γH2AX signal from the XY body throughout chromosome 14 in 7.05% of the cells analyzed. The potential causes of the observed infertility, i.e. activation of meiotic checkpoints and/or silencing of genes necessary for the progression of meiosis, are discussed.
Three autosomal chromosome translocations associated with repeated early embryonic loss (REEL) in the domestic horse (Equus caballus)
Authors: Lear T.L. , Lundquist J. , Zent W.W. , Fishback, Jr. W.D. , Clark A.
Published: April 2008

Repeated early embryonic loss (REEL) represents a considerable economic loss to the horse industry. Mares that experience REEL may be overlooked as poten- tial carriers of a chromosome abnormality. Here we report three different autosomal translocations in Thoroughbred mares presented for chromosome analysis because of REEL. The karyotypes were 64,XX,t(1;21), 64,XX,t(16;22), and 64,XX,t(4;13), respectively. In order to confirm the chromosomes involved in the translocations, to map the breakpoints, and to determine if the translocations were reciprocal, genes surrounding the breakpoints were identified using existing maps and from the newly assembled horse genome sequence. Bacterial artificial chromosomes containing the genes of interest were identified and mapped to the translocation chromosomes by fluorescence in situ hybridization (FISH). FISH confirmed that the t(16;22) and t(4;13) translocations were reciprocal, while the t(1;21) was not. The breakpoints on horse chromosomes 1 and 16 appear to be the same or near breakpoints previously identified in translocations. These breakpoints are at the fusion boundary of human chromosomes 10 and 15 on horse chromosome 1 and at human chromosome 3p and 3q on horse chromosome 16. These sites may represent ancient breakpoints reused during equid evolution. Overall, chromosome abnormalities may have a greater influence on mare fertility than previously known. Thus, it is important to karyotype subfertile mares exhibiting REEL.
A case of an intersex horse with 63,X/64,XX/65,XX,del(Y)(q?) karyotype
Authors: Bugno M. , Ząbek T. , Golonka P. , Pieńkowska-Schelling A. , Schelling C. , Słota E.
Published: April 2008

Cytogenetic and molecular genetic studies of an intersex horse have been carried out. The investigated animal had overall male body conformation; however, its external genitalia consisted of incompletely developed vulva and penis. The X and Y chromosome painting probes detected three cell lines in the examined horse: 63,X, 64,XX and 65,XX with a fragment of a Y chromosome (del Y). The DNA analysis with the PCR and PCR/RFLP methods showed absence of SRY,AMELY and ZFY genes as well as of six Y microsatellite markers (YM2, YP9, YJ10, YE1, YH12, and YA16). These results suggest that the Y chromosome fragment detected in the investigated animal was the result of a deletion of a euchromatic fragment comprising the above-mentioned markers.
High-resolution comprehensive radiation hybrid maps of the porcine chromosomes 2p and 9p compared with the human chromosome 11
Authors: Liu W.-S. , Yasue H. , Eyer K. , Hiraiwa H. , Shimogiri T. , Roelofs B. , Landrito E. , Ekstrand J. , Treat M. , Paes N. , Lemos M. , Griffith A.C. , Davis M.L. , Meyers S.N. , Yerle M. , Milan D. , Beever J.E. , Schook L.B. , Beattie C.W.
Published: April 2008

We are constructing high-resolution, chromosomal ‘test’ maps for the entire pig genome using a 12,000-rad WG-RH panel (IMNpRH212,000-rad)to provide a scaffold for the rapid assembly of the porcine genome sequence. Here we present an initial, comparative map of human chromosome (HSA) 11 with pig chromosomes (SSC) 2p and 9p. Two sets of RH mapping vectors were used to construct the RH framework (FW) maps for SSC2p and SSC9p. One set of 590 markers, including 131 microsatellites (MSs), 364 genes/ESTs, and 95 BAC end sequences (BESs) was typed on the IMNpRH212,000-rad panel. A second set of 271 markers (28 MSs, 138 genes/ESTs, and 105 BESs) was typed on the IMpRH7,000-rad panel. The two data sets were merged into a single data-set of 655 markers of which 206 markers were typed on both panels. Two large linkage groups of 72 and 194 markers were assigned to SSC2p, and two linkage groups of 84 and 168 markers to SSC9p at a two-point LOD score of 10. A total of 126 and 114 FW markers were ordered with a likelihood ratio of 1000:1 to the SSC2p and SSC9p RH12,000-rad FW maps, respectively, with an accumulated map distance of 4046.5 cR12,000 and 1355.2 cR7,000 for SSC2p, and 4244.1 cR12,000 and 1802.5 cR7,000 for SSC9p. The kb/cR ratio in the IMNpRH212,000-rad FW maps was 15.8 for SSC2p, and 15.4 for SSC9p, while the ratio in the IMpRH7,000-rad FW maps was 47.1 and 36.3, respectively, or an ∼3.0-fold increase in map resolution in the IMNpRH12,000-rad panel over the IMpRH7,000-rad panel. The integrated IMNpRH12,000-rad andIMpRH7,000-rad maps as well as the genetic and BAC FPC maps provide an inclusive comparative map between SSC2p, SSC9p and HSA11 to close potential gaps between contigs prior to sequencing, and to identify regions where potential problems may arise in sequence assembly.
Chromosomal expression and localization of aphidicolin-induced fragile sites in the standard karyotype of river buffalo (Bubalus bubalis)
Authors: Nicodemo D. , Coppola G. , Pauciullo A. , Cosenza G. , Ramunno L. , Ciotola F. , Peretti V. , Di Meo G.P. , Iannuzzi L. , Rubes J. , Di Berardino D.
Published: April 2008

The present study reports on the chromosomal expression and localization of aphidicolin-induced fragile sites in the standard karyotype of river buffalo (Bubalus bubalis, 2n = 50) with the aim of establishing a ‘fragile site map’ of the species. Totally, 400 aphidicolin-induced breakages were analyzed from eight young and clinically healthy animals, four males and four females; these breakages were localized in 106 RBG-negative chromosome bands or at the band-interband regions. The number of breakages per chromosome did not vary statistically ‘among’ the animals investigated but the differences among individual chromosomes were highly significant thus indicating that the chromosomal distribution of the breakages is not random and appears only partially related to chromosome length. Fragile sites were statistically determined as those chromosomal bands showing three or more breakages. In the river buffalo karyotype, 51 fragile sites were detected and localized on the standardized ideogram of the species. The most fragile bands were as follows: 9q213 with 24 breakages out of 400; 19q21 with 16, 17q21 and inacXq24 with 15, 15q23 with 13 and 13q23 with 12 breaks, respectively. Previous gene mapping analysis in this species has revealed that the closest loci to these fragile sites contain genes such as RASA1 and CAST (9q214), NPR3 and C9 (19q19), PLP and BTK (Xq24-q25), OarCP09 (15q24), and EDNRB (13q22) whose mutations are responsible for severe phenotypic malformations and immunodeficiency in humans as well as in mice and meat quality in pigs. Further cytogenetic and molecular studies are needed to fully exploit the biological significance of the fragile sites in karyotype evolution of domestic animals and their relationships with productive and reproductive efficiency of livestock.
Increased SCE levels in Mediterranean Italian buffaloes affected by limb malformation (transversal hemimelia)
Authors: Peretti V. , Ciotola F. , Albarella S. , Restucci B. , Meomartino L. , Ferretti L. , Barbieri V. , Iannuzzi L.
Published: April 2008

In recent years some buffalo farms in Campania have reported the birth of calves with limb malformation, especially with transversal hemimelia. We investigated 20 Mediterranean Italian buffaloes (8 males and 12 females) from one day to six months of age, of which 10 were affected by transversal hemimelia (group 1) and 10 were healthy controls (group 2). The following clinical and radiological patterns were observed in the malformed animals: hind limbs amputated, the right amputated off the second tarsus bones and the left amputated off the proximal epiphysis metatarsus, and the right thoracic limb hypoplasic (1 female); left hind limb amputated off the proximal epiphysis metatarsus (2 females and 1 male); left hind limb amputated off the third tarsus bones (1 female); left hind limb amputated off the tibia (1 female and 1 male); left hind limb amputated off the distal epiphysis metatarsus (1 female); left hind limb amputated off the first phalanx (1 male); right hind limb amputated off the proximal epiphysis metatarsus (1 male). In their malformed limbs all the animals presented more or less developed outlines of claws. The mean rate of SCE/cell in animals with transversal hemimelia was 8.80 ± 3.19, that of the controls 6.61 ± 2.73. The difference was statistically significant (P < 0.001).
Emergency Surgery for Complicated Colorectal Cancer
Authors: Nascimbeni Riccardo , Ngassa Hyginus , Di Fabio Francesco , Valloncini Eleonora , Di Betta Ernesto , Salerni Bruno
Published: April 2008

Background/Aims: Emergency procedures for colorectal cancer have worse outcomes than elective resections. Temporal trends in emergency surgery are analyzed by comparing two decade-related series of colorectal cancer patients. Methods: The clinical data of 985 patients undergoing colorectal cancer surgery were collected during two decades (1975–1984 and 1995–2004). Rates of emergency surgery, operative mortality, 5-year cancer-related and overall survival were compared retrospectively. Results: The rate of emergency surgery decreased from 81 out of 513 cases (16%) during 1975–1984 to 41 out of 471 cases (9%) during 1995–2004 (p = 0.005). Over the same time, the rate of curative resections in emergency increased from 46% (37/81 cases) to 76% (31/41 cases) (p < 0.001), while patient and tumor characteristics remained similar. Operative mortality after emergency procedures decreased from 14% (11 deaths) to 5% (2 deaths) and cancer-related survival increased from 21 to 42% (p = 0.03). However, when excluding palliative procedures, survival after emergency surgery increased from 52 to 58%, while after elective treatment it increased from 56 to 78% (p < 0.001). Conclusions: Frequency and operative mortality of emergency colorectal cancer surgery decreased substantially from 1975–1984 to 1995–2004. No significant improvement in long-term survival was observed when curative emergency resections only were considered. Further efforts are needed to reverse the diverging trend of long-term outcomes between emergency and elective curative procedures.
Immunological Consequences of Laparoscopic versus Open Transhiatal Resection for Malignancies of the Distal Esophagus and Gastroesophageal Junction
Authors: Scheepers J.J.G. , Sietses C. , Bos D.G. , Boelens P.G. , Teunissen C.M.W. , Ligthart-Melis G.C. , Cuesta M.A. , van Leeuwen P.A.M.
Published: April 2008

Background/Aim: Surgery remains the only curative therapy for esophageal cancer. The objective of the current study was to evaluate the impact of laparoscopic transhiatal esophagectomy versus open transhiatal esophagectomy on both inflammatory and immunological responses. Methods: Seventeen patients undergoing laparoscopic or open surgery were included in the study. The postoperative inflammatory response was assessed by measuring WBC count and CRP, IL-6, IL-8, soluble TNF I and II receptor, and elastase levels. The postoperative immune function was assessed by measuring the monocyte HLA-DR expression. LPS-binding protein (LBP) and bactericidal/permeability-increasing protein (BPI) were measured to evaluate bacterial translocation. Results: The IL-6 level increased significantly more in the patients who received open surgery as compared with the laparoscopic group. Both LBP and BPI increased predominantly in the laparoscopic group as compared with the group who received open surgery. No difference was found in HLA-DR expression between the two groups. Conclusion: Although both laparoscopic and conventional esophageal resections result in an activation of the inflammatory response, this study suggests that this response could be less pronounced after the laparoscopic approach. However, in the laparoscopic group higher LBP and BPI levels were seen, suggesting an increased endotoxemia. We postulate that the persistently elevated abdominal pressure results in a loss of mucosal barrier function, resulting in bacterial translocation. The cellular acidification of the cells of the peritoneum induced by CO2 insufflation, however, blunts the expected inflammatory response.
Lipopolysaccharides Modulate Allergen-Specific Immune Regulation in a Murine Model of Mucosal Tolerance Induction
Authors: Gerhold Kerstin , Avagyan Angela , Reichert Eva , Blümchen Katharina , Wahn Ulrich , Hamelmann Eckard
Published: April 2008

Background: Farming has been widely reported to be associated with decreased risk of developing atopic disorders, but underlying immunomodulatory mechanisms are still not fully defined. We delineated T-cell functions after induction of mucosal tolerance in the context of intranasally delivered organic dust compounds, lipopolysaccharides (LPS). Methods: BALB/c mice were pretreated intranasally with ovalbumin (OVA) with or without LPS (Escherichia coli) three times (days –21, –14, –7) prior to systemic OVA sensitization (days 1 and 14) and airway allergen challenges (days 28–30). CD4+ spleen T cells from pretreated and sensitized donors were characterized for cytokine function, and transferred into naive recipients prior to subsequent OVA sensitization and challenges. Results: Intranasal OVA pretreatment suppressed Th2-mediated immune and inflammatory responses and enhanced frequency of regulatory T cells in OVA-sensitized and -challenged mice. Addition of LPS to OVA, but not LPS alone, inhibited development of allergen-induced sensitization and eosinophilic airway infiltration, and markedly enhanced allergen-specific IgG1 serum levels and frequencies of IL-10- and IFN-γ-producing CD4+ T cells. Transfer of CD4+ spleen T cells from OVA-pretreated animals protected naive recipients against subsequent allergen sensitization and airway disease, whereas transfer from LPS/OVA-pretreated animals only protected against allergen sensitization. Conclusion: Microbial LPS modulated mucosal tolerance by inducing allergen-specific IgG1 production and distinct effector CD4+ T cells with a mixed regulatory/Th1 phenotype. Organic dust components such as LPS might therefore be important immune modulators in naturally occurring or preventive allergen-specific tolerance induction.
Strongyloides stercoralis: A Rare Cause of Obstructive Duodenal Stenosis
Authors: Juchems Markus S. , Niess Jan Hendrik , Leder Gerhard , Barth Thomas F. , Adler Guido , Brambs Hans-Juergen , Wagner Martin
Published: April 2008

Background: Strongyloidiasis is a rare helminthic infection in Europe, and it may cause duodenal obstruction. Methods: We report a patient who was admitted to our Medical Department with nausea and repeated vomiting since 10 years until food intake became impossible. Subsequent investigations revealed a duodenal obstruction at the upper third of the duodenum, as well as enterocolitis of the terminal ileum with eosinophils dispersed throughout the mucosa. Since food intake was still not possible after treatment with a course of i.v. PPI and prokinetic applications, we decided to perform a resection of the upper duodenum with Y-Roux reconstruction. Results: The histopathological examination of the resected specimen revealed strongyloidiasis. Conclusion: Parasite infections such as strongyloidiasis represent a rare differential diagnosis of duodenal obstruction especially if patients originate from endemic regions.
Pilot Study: Absorption and Efficacy of Multiple Hormones Delivered in a Single Cream Applied to the Mucous Membranes of the Labia and Vagina
Authors: Glaser Rebecca L. , Zava David T. , Wurtzbacher Doug
Published: April 2008

Background/Aims: There is a lack of evidence in the literature supporting vaginal application of a combination hormone-containing cream for local and systemic symptom relief. This pilot study examined the extent of absorption of a single cream containing estriol, estradiol, progesterone, DHEA, and testosterone. Methods: A combination cream was administered to 12 postmenopausal women in two differing doses over two independent time periods. Following 28 days (arm 1) and an additional 14 days (arm 2), measurement of hormones in saliva and blood and measurements of symptom relief, patient tolerability, and health-related quality of life (HRQoL) were obtained. Results: The dosage and time of evaluation for study arm 1 was not ideal for providing documented increases in hormone levels. HRQoL measurements supported measured improvement in this arm. The second arm did document absorption of the various hormones when given vaginally. Conclusion: This study is the first documenting systemic absorption of multiple hormones by both saliva and blood as well as improvement of HRQoL. This therapy was generally well-tolerated with only 2 patients experiencing minor irritation, not necessitating discontinuation. Additional studies in larger numbers of patients will provide better knowledge for clinicians wanting to provide similar therapy at the lowest effective dose.
Hysterosalpingographic Tubal Abnormalities and HIV Infection among Black Women with Tubal Infertility in Sub-Saharan Africa
Authors: Adesiyun Adebiyi Gbadebo , Ameh C.A. , Eka A.
Published: April 2008

Background: Tubal factor remains a common cause of infertility. The association of HIV infection and tubal infertility is a cause for concern. Objective: To determine hysterosalpingographic tubal abnormalities and HIV infection among patients with tubal infertility. Results: Over a 4-year period, 207 patients were analyzed. Of these, 174 (84.1%) presented with secondary infertility and 33 (15.9%) with primary infertility. The patients’ age range was 21–48 years and mean age was 36.2 years. One hundred and two (49.3%) patients had a history of induced abortion. Concordant bilateral tubal occlusion was found in 139 (67.2%) patients while 68 (32.8%) had discordant bilateral tubal occlusion. Of the 414 fallopian tubes studied, proximal tubal occlusion was found in 66 (15.9%) cases and distal tubal occlusive pathology occurred in 348 (84.1%). An HIV positivity rate of 13.5% was recorded. Distal tubal occlusion with hydrosalpinx was more associated with HIV infection in this series. Conclusion: A high HIV positivity rate was recorded among the patients with tubal infertility compared to the general population. There is prepondence of distal tubal occlusion in infertile women with tubal factor.
Chromosomal Mosaic in a Girl with some Features of Mongolism
Authors: Lindsten J. , Alvin A. , Gustavson K.-H. , Fraccaro M.
Published: April 2008

Chromosomal mosaic of the normal/trisomy 21 type was found in a two year old girl. The patient had some of the symptoms characteristic of mongolism but was of average intelligence. The mosaic pattern was found consistently in two blood and three skin cultures. On the basis of the few similar cases reported it is not possible as yet to correlate the phenotype with the relative proportions of the different karyotypes found at cytological analysis.
Human Oögenesis
Authors: Ohno S. , Klinger H.P. , Atkin N.B.
Published: April 2008

In humans, the developmental sequence of oögenesis is considerably different from that of spermatogenesis. Oögonia cease to propagate while the female is in the fifth or sixth month of fetal life, and all oöcytes complete the entire process of first meiotic prophase several weeks before the end of gestation. Thus, preparation for segretion of one haploid set from the other is completed during the female’s prenatal life. Oöcytes then enter the long, interphase-like dictyotene stage during which the cytoplasm stores nutrients. At its shortest, the dictyotene stage lasts about 12 years; at its longest, about 50 years. When the estrus cycle begins, one or more oöcytes at a time resume meiosis from diakinesis shortly before being ovulated into the Fallopian tube. Second meiosis is usually completed only after an ovum has been fertilized.
Aberrations Induced in Human Leukocyte Chromosomes by 3H-Labeled Nucleosides
Authors: Bender M.A. , Gooch P.C. , Prescott D.M.
Published: April 2008

Metaphase chromosomal aberrations were produced by tritium-labeled thymidine and by tritium-labeled uridine incorporated into human peripheral leukocytes in vitro. The distribution of aberration types is different from that of aberrations induced by X rays, and one type of lesion was produced by tritium that has not been seen in material treated with X rays. No correlation between the distribution of chromosomal breaks and the distribution of label in autoradiographs was observed, although more aberrations occurred, as expected, in heavily labeled cells. The breakage frequencies observed correspond to single acute doses of up to about 100 r of hard X rays.
The Relationship between the Deoxyribonucleic Acid Content and the Ploidy of Human Tumours
Authors: Atkin N.B.
Published: April 2008

The relationship between the modal DNA content of human tumour cells in interphase and the ploidy of the tumours has been discussed. Data on chromosome number, the DNA content of dividing cells and the number of sex chromatin bodies per cell have been considered in relation to the frequency-distribution of the DNA values of interphase cells. It is concluded that information on all of these may be needed to accurately characterize a tumour. However, for most tumours, the ploidy-level indicated by the modal interphase DNA value is in agreement with that obtained from chromosome counts. In a few tumours, the main interphase DNA mode is in the tetraploid or hypertetraploid region and there is also a small near-diploid mode. Two such cases are illustrated, and it is concluded from the data provided that (i) other regions of the tumour may show a reversed picture, the main mode being in the diploid region although there is still a substantial tetraploid mode, and (ii) the majority of metaphases in such tumours may sometimes have near-diploid chromosome numbers. The significance of these findings is discussed. Data on nuclear size obtained on histological sections of carcinoma of the cervix suggest that usually there is consistency of ploidy in different regions of a given tumour; where a section shows variation, other sections from different regions usually show similar variation.
Chromosome Analysis from Capillary Blood
Authors: Edwards J.H.
Published: April 2008

A simple method is described for making chromosome preparations from a very small volume of blood. This can be obtained from skin puncture, a procedure not requiring any medical supervision.
Cytological Study of an X-Autosome Translocation in Mus musculus
Authors: Ohno S. , Cattanach B.M.
Published: April 2008

Earlier genetic studies on this stock of mice with an X-autosome translocation revealed that wild-type alleles of pink-eye and chinchilla of linkage group I have been translocated to the X. When the Xt was accompanied by an Xn, animals heterozygous for pp and cchcch showed variegated coat colors but the Xt alone led only to the wild-type coat color. The cytological investigation reported herein revealed the following information: 1. The translocation was non-reciprocal. About one third of the autosome representing linkage group I was transposed into the X, making the Xt about 20% longer than the Xn. 2. The autosomal insertion behaved as an integral part of the X, manifesting positive heteropyenosis when the X itself assumed this condition. 3. In the skin of animals with a variegated phenotype, the cc patches were apparently populated by cells containing a condensed Xt, while in wild-type patches from the same animal, the Xt was isopyenotic, behaving in the same manner as the euchromatic autosomes. These findings support Lyon’s hypothesis explaining the somatic variegation in Mus musculus due to X-autosome translocation (1961, 1962). The present study on skin cells of XtXn females has yielded convincing evidence that the mammalian female is indeed a natural mosaic.
Polyploidy with Chromosome Breakage at Meiosis in the Human Male
Authors: Darlington C.D. , Haque A.
Published: April 2008

Chromosome Breakage is correlated with abnormal Polyploidy at Meiosis in man.