bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetic Behavior of Polycrystalline Neodymium, Holmium, and Erbium from 300 to 1500°K
Authors: Arajs Sigurds , Miller D. S.
Published: June 2005

The paramagnetic susceptibilities of polycrystalline Nd, Ho, and Er have been determined from about 300 to 1500°K by the Faraday method. The inverse paramagnetic susceptibility versus temperature (1/χ vs T)curve for Nd at high temperatures show two slight anomalies associated with a solid state phase transformation and the melting point, respectively. The paramagnetic susceptibility of hcp Nd does not satisfy the Weiss-Curie law due to the partial population of the energy levels above the ground state I9/24, The paramagneticsusceptibility of Ho and Er is representable by the Weiss-Curie law. The experimental Bohr magneton numbers are in satisfactory agreement with those predicted by the Van Vleck theory.
Magnetic Properties of Uranium Digermanide
Authors: Olsen Clayton E.
Published: June 2005

Investigations on the magnetic properties of actinide element intermetallic compounds has disclosed that UGe2 and PuGe2 are ferromagnetic with magnetic moments greater than 0.803 and 0.144 Bohr magneton per molecule respectively at 4°K. Electrical resistivity measurements on UGe2 indicate an interaction of the conduction electrons with the local spin which produces ferromagnetism. Also the electrical resistivity of USi2, which is not ferromagnetic, was measured for comparison.
Low-Temperature X-Ray Diffraction Studies on Vanadium Sesquioxide
Authors: Warekois E. P.
Published: June 2005

X-ray diffraction patterns and microphotographs were obtained from single crystals and powder samples of V2O3, cooled to liquid nitrogen temperatures. The c axis, in the hexagonal unit cell, expanded 5.8×10−6/°Cwhile the a axis contracted 22.9×10−6/°C, over the range from room temperature to the transformation temperature of about minus 145°C. Below this temperature a microphotograph showed a typical martensitic structure. The low-temperature x-ray diffraction reflections split for all reflections except those of the (000l)type. The (000l) type reflections indicated a lattice contraction below the transformation. Those x-ray reflections that split showed expansions in the interplanar spacings. The low-temperature powder pattern could be indexed on the basis of a monoclinic unit cell; a = 8.57, b = 4.98 and c = 13.88 A with β = 91.6°.
Reelin promoter hypermethylation in schizophrenia
Authors: Grayson Dennis R. , Jia Xiaomei , Chen Ying , Sharma Rajiv P. , Mitchell Colin P. , Guidotti Alessandro , Costa Erminio
Published: June 2005

Reelin mRNA and protein levels are reduced by ≈50% in various cortical structures of postmortem brain from patients diagnosed with schizophrenia or bipolar illness with psychosis. In addition, the mRNA encoding the methylating enzyme, DNA methyltransferase 1, is up-regulated in the same neurons that coexpress reelin and glutamic acid decarboxylase 67. We have analyzed the extent and pattern of methylation within the CpG island of the reelin promoter in genomic DNA isolated from cortices of schizophrenia patients and nonpsychiatric subjects. Ten (The Stanley Foundation Neuropathology Consortium) and five (Harvard Brain Collection) schizophrenia patients and an equal number of nonpsychiatric subjects were selected from each brain collection. Genomic DNA was isolated, amplified (from base pair -527 to base pair +322) after bisulphite treatment, and sequenced. The results show that within the promoter region there were interesting regional variations. There was increased methylation at positions -134 and 139, which is particularly important for regulation, because this portion of the promoter is functionally competent based on transient transfection assays. This promoter region binds a protein present in neuronal precursor nuclear extracts that express very low levels of reelin mRNA; i.e., an oligonucleotide corresponding to this region and that contains methylated cytosines binds more tightly to extracts from nonexpressing cells than the nonmethylated counterpart. Collectively, the data show that this promoter region has positive and negative properties and that the function of this complex cis element relates to its methylation status.
Different hunting strategies select for different weights in red deer
Authors: Martı́nez Marı́a , Rodrı́guez-Vigal Carlos , Jones Owen R , Coulson Tim , Miguel Alfonso San
Published: June 2005

Much insight can be derived from records of shot animals. Most researchers using such data assume that their data represents a random sample of a particular demographic class. However, hunters typically select a non-random subset of the population and hunting is, therefore, not a random process. Here, with red deer (
Cervus elaphus
) hunting data from a ranch in Toledo, Spain, we demonstrate that data collection methods have a significant influence upon the apparent relationship between age and weight. We argue that a failure to correct for such methodological bias may have significant consequences for the interpretation of analyses involving weight or correlated traits such as breeding success, and urge researchers to explore methods to identify and correct for such bias in their data.
Bmi-1 promotes neural stem cell self-renewal and neural development but not mouse growth and survival by repressing the p16Ink4a and p19Arf senescence pathways
Authors: Molofsky Anna V. , He Shenghui , Bydon Mohammad , Morrison Sean J. , Pardal Ricardo
Published: June 2005

Bmi-1 is required for the post-natal maintenance of stem cells in multiple tissues including the central nervous system (CNS) and peripheral nervous system (PNS). Deletion of Ink4a or Arf from Bmi-1-/- mice partially rescued stem cell self-renewal and stem cell frequency in the CNS and PNS, as well as forebrain proliferation and gut neurogenesis. Arf deficiency, but not Ink4a deficiency, partially rescued cerebellum development, demonstrating regional differences in the sensitivity of progenitors to p16Ink4a and p19Arf. Deletion of both Ink4a and Arf did not affect the growth or survival of Bmi-1-/- mice or completely rescue neural development. Bmi-1 thus prevents the premature senescence of neural stem cells by repressing Ink4a and Arf, but additional pathways must also function downstream of Bmi-1.
Magnetic resonance imaging as a sole method for the morphological and functional evaluation of live kidney donors
Authors: El‐Diasty Tarek A. , El‐Ghar Mohamed E. Abo , Shokeir Ahmed A. , Gad Hossam M. , Wafa Ehab W. , El‐Azab Mohamed E. , El‐Din Ahmed B. Shehab , Ghoneim Mohamed A.
Published: June 2005

In this section, authors from Mansoura describe their experience with MRI as the sole method for the morphological and functional evaluation of live kidney donors. They recommend this technique in both instances.

A series of studies from Detroit show that oxalate and hyperoxaluria induced free‐radical generation, which resulted in injury to renal tubular cells. In this paper they show for the first time that hyperoxaluria‐induced injury promotes individual calcium oxalate crystal attachment in the renal tubules. They also showed that this was prevented by vitamin E treatment.

OBJECTIVE

To evaluate gadolinium‐enhanced dynamic magnetic resonance imaging (MRI) as the sole method for the anatomical and functional assessment of potential live‐kidney donors.

SUBJECTS AND METHODS

The study included 50 consecutive kidney donors; in addition to routine donor evaluation, the kidney was imaged with Gd‐enhanced dynamic MRI, which was also used for selectively determining the glomerular filtration rate (GFR) of each kidney. All donors had a m99Tc‐mercaptoacetyltriglycine (MAG3) renal scan as the reference standard to measure GFR. The anatomical results of MRI were compared with the findings at donor nephrectomy, and the GFR estimated from MRI compared with that from MAG3 scintigraphy.

RESULTS

MR angiography had 100% sensitivity, 94% specificity and 96% overall accuracy for detecting the number of renal arteries, and 100% sensitivity, 98% specificity and 98% overall accuracy for the number of renal veins. There was a close correlation (r = 0.54, P < 0.01) between the GFR of each kidney estimated by MRI or MAG3. For the right and left kidneys the mean isotope clearance was not significantly different from that of mean MRI clearance. MR urography allowed visualization of the urinary tract and the detection of any abnormality.

CONCLUSION

Gd‐enhanced dynamic MRI can provide accurate information about the anatomy of the urinary tract and vasculature of the kidney, and can be used to accurately estimate the selective GFR of each kidney. Therefore, we recommend MRI as a single imaging diagnostic method for assessing potential live kidney donors.
MAGNETIC RESONANCE IMAGING APPEARANCE OF SUSPECTED ISCHEMIC MYELOPATHY IN DOGS
Authors: Abramson Carley J. , Garosi Laurent , Platt Simon R. , Dennis Ruth , McConnell J. Fraser
Published: June 2005

Ischemia and infarction of the spinal cord is a known cause of acute spinal injury in dogs. Currently, the diagnosis of spinal cord infarction in small animals is based on history, clinical signs, and the exclusion of other differentials with radiography and myelography. It is a diagnosis only confirmed through necropsy examination of the spinal cord. The aim of this paper is to describe the Magnetic resonance imaging (MRI) findings of the spinal cord of dogs with suspected spinal cord infarcts to utilize this technology for antemortem support of this diagnosis. This retrospective study evaluated the spinal MR examinations of 11 dogs with acute onset of asymmetric nonpainful myelopathies. All patients except one (imaged at 2 months) were imaged within 1 week of clinical signs and managed conservatively with minimal medical and no surgical intervention. They were followed clinically for a minimum of 4 months after discharge. MR findings in all dogs were characterized by focal, intramedullary, hyperintense lesions on T2‐weighted images with variable contrast enhancement similar to what is reported in humans. Though it could not be used to diagnose spinal cord infarction definitively, MRI was useful in excluding extramedullary spinal lesions and supporting intramedullary infarction as a cause of the acute neurologic signs. Together with the history and clinical examination findings, MRI is supportive of a diagnosis of spinal cord infarction.
Marked Decline in Atmospheric Carbon Dioxide Concentrations During the Paleogene
Authors: Pagani Mark , Zachos James C. , Freeman Katherine H. , Tipple Brett , Bohaty Stephen
Published: June 2005

The relation between the partial pressure of atmospheric carbon dioxide (
p
CO
2
) and Paleogene climate is poorly resolved. We used stable carbon isotopic values of di-unsaturated alkenones extracted from deep sea cores to reconstruct
p
CO
2
fromthe middle Eocene to the late Oligocene (∼45 to 25 million years ago). Our results demonstrate that
p
CO
2
ranged between 1000 to 1500 parts per million by volume in the middle to late Eocene, then decreased in several steps during the Oligocene, and reached modern levels by the latest Oligocene. The fall in
p
CO
2
likely allowed for a critical expansion of ice sheets on Antarctica and promoted conditions that forced the onset of terrestrial C
4
photosynthesis.
LATE-TIME PHANTOM UNIVERSE IN SO(1, 1) DARK ENERGY MODEL WITH EXPONENTIAL POTENTIAL
Authors: WEI YI-HUAN
Published: June 2005

We discuss the late-time property of universe and phantom field in the SO(1, 1) dark energy model for the potential V = V0e-βΦα with α and β two positive constants. We assume in advance some conditions satisfied by the late-time field to simplify equations, which are confirmed to be correct from the eventual results. For α < 2, the field falls exponentially off and the phantom equation of state rapidly approaches -1. When α = 2, the kinetic energy ρk and the coupling energy ρc become comparable but there is always ρk < -ρc so that the phantom property of field proceeds to hold. The analysis on the perturbation to the late-time field Φ illustrates the square effective mass of the perturbation field is always positive and thus the phantom is stable. The universe considered currently may evade the future sudden singularity and will evolve to de Sitter expansion phase.
PHYSICS AT ELSA, ACHIEVEMENTS AND FUTURE
Authors: THOMA U.
Published: June 2005

At ELSA interesting results on baryon resonances have been obtained by the CB-ELSA, the CBELSA/TAPS and the SAPHIR collaborations. New resonances were found, in particular a new D15(2070) decaying into pη, was recently observed by the CB-ELSA experiment. The availability of a polarized beam and a polarized target did allow to measure the GDH sum rule up to 2.9 GeV. In the future double polarization experiments will be performed using the Crystal Barrel detector together with new forward detector components. These polarization observables will provide important additional information for the partial wave analyses performed to extract the contributing resonances and their parameters from the data.
PHYSICS AT COSY
Authors: MACHNER H.
Published: June 2005

The COSY accelerator in Jülich is presented together with its internal and external detectors. The physics programme performed recently is discussed with emphasis on strangeness physics.
MEASURING THE GLUON POLARIZATION
Authors: KUNNE FABIENNE
Published: June 2005

After a series of experiments measuring the quark contribution ΔΣ to the nucleon spin in the 90's, a new generation of experiments is exploring the gluon contribution. First results are already obtained for the value of ΔG/G at a few values of xg. More results are expected in the future from COMPASS at CERN and RHIC spin at Brookhaven.
HYBRID AND CONVENTIONAL BARYONS IN THE FLUX-TUBE AND QUARK MODELS
Authors: PAGE PHILIP R.
Published: June 2005

The status of conventional baryon flux-tubes and hybrid baryons is reviewed. Recent surprises are that a model prediction indicates that hybrid baryons are very weakly produced in glue-rich Ψ decays, and an analysis of electro-production data concludes that the Roper resonance is not a hybrid baryon. The baryon decay flux-tube overlap has been calculated in the flux-tube model, and is discussed here. The behavior of the overlap follows naïve expectations.
STRUCTURE OF LIGHT AND HEAVY PENTAQUARKS
Authors: STANCU FL.
Published: June 2005

Light and heavy pentaquarks are described within a constituent quark model based on a spin-flavor hyperfine interaction. In this model the lowest state acquires positive parity. The masses of the light antidecuplet members are calculated dynamically using a variational method. It is shown that the octet and antidecuplet states with the same quantum numbers mix ideally due to SU (3)F breaking. Masses of the charmed antisextet pentaquarks are predicted within the same model.
NUCLEON AND ROPER WAVEFUNCTIONS FROM OVERLAP FERMIONS
Authors: CHEN YING
Published: June 2005

By applying a spatially extended sink operator, the nucleon two-point functions are calculated in Coulomb gauge from quenched lattice QCD with overlap fermions. The Bethe-Salpeter wavefunctions of nucleon and Roper resonance are extracted at different quark masses. The typical size of nucleon is about 0.7 fm, which seems insensitive to the quark masses involved in this work. It is also found that the wavefunction of Roper has a radial node.
RELATIVISTIC EFFECTS IN TWO PHOTON DECAY OF 0-+ QUARKONIUM
Authors: ZHOU H. Q. , ZOU B. S.
Published: June 2005

Relativistic effects in two photon decay of 0-+ quarkonium are investigated with a relativistic phenomenological approach. Comparing with the non-relativistic approximation, the relativistic phenomenological approach gives corrections coming from three sources: [Formula: see text] relative momentum distribution, [Formula: see text] relative energy distribution and description of quark spinors in the meson. These relativistic effects are studied in detail for [Formula: see text] and [Formula: see text] systems.
ANTIPROTON-PROTON RESONANT LIKE CHANNELS IN $J/\psi\to\gamma p\bar p$ DECAYS
Authors: LOISEAU B. , WYCECH S.
Published: June 2005

The BES collaboration has recently observed a strong enhancement close to the proton-antiproton, [Formula: see text] threshold in the J/ψ decays into [Formula: see text]. Such a structure can be explained by a traditional nucleon-antinucleon, [Formula: see text], model. The near threshold 11S0 bound state and/or the well-established 13P0 resonant state found in this [Formula: see text] interaction can adequately describe the BES data.
TRANSFER MATRIX METHOD FOR ELECTRON-PHONON INTERACTION IN MULTILAYER SPHERICAL HETEROSTRUCTURES
Authors: WEI SHU YI , HUANG WEN DENG , XIA CONG XIN , WU HUA RUI
Published: June 2005

Within the framework of the dielectric-continuum model, the polarization eigenvector, the dispersion relations, and the electron-phonon interaction Fröhlich-like Hamiltonian of the interface optical (IO) phonons in multilayer spherical heterostructures are derived by using transfer-matrix method. The dispersion relations and electron-phonon coupling function strengths of the IO phonons are investigated for 5-layer CdS/HgS/CdS/HgS/H 2 O spherical heterostructures. We find that there are seven IO phonon branches in 5-layer CdS/HgS/CdS/HgS/H 2 O spherical heterostructures, but only one has a more important contribution to the coupling function [Formula: see text].
INHOMOGENEOUS DUST COLLAPSE WITH COSMOLOGICAL CONSTANT
Authors: GHOSH S. G.
Published: June 2005

We investigate the occurrence of naked singularities in the gravitational collapse of an inhomogeneous dust cloud in an expanding de Sitter background — a piece of Tolman–Bondi–de Sitter space–time. It turns out that the collapse proceed in the same way as in the Minkowski background, i.e., the strong curvature naked singularities form and thus violate the cosmic censorship conjecture. Our result unambiguously support the fact that the asymptotic flatness of space–time is not a necessary ingredient for the development of naked singularities.
AMP-18 protects barrier function of colonic epithelial cells: role of tight junction proteins
Authors: Walsh-Reitz Margaret M. , Huang Erick F. , Musch Mark W. , Chang Eugene B. , Martin Terence E. , Kartha Sreedharan , Toback F. Gary
Published: June 2005

Antrum mucosal protein (AMP)-18 and a synthetic peptide of amino acids 77–97 have mitogenic and motogenic properties for epithelial cells. The possibility that AMP-18 is also protective was evaluated in the colonic mucosa of mice and monolayer cultures of human colonic epithelial Caco-2/bbe (C2) cells. Administration of AMP peptide to mice with dextran sulfate sodium (DSS)-induced colonic injury delayed the onset of bloody diarrhea and reduced weight loss. Treatment of C2 cells with AMP peptide protected monolayers against decreases in transepithelial electrical resistance induced by the oxidant monochloramine, indomethacin, or DSS. A molecular mechanism for these barrier-protective effects was sought by asking whether AMP peptide acted on specific tight junction (TJ) proteins. Immunoblots of detergent-insoluble fractions of C2 cells treated with AMP peptide exhibited increased accumulation of specific TJ proteins. Occludin immunoreactivity was also increased in detergent-insoluble fractions obtained from colonic mucosal cells of mice injected with AMP peptide. Observations using laser scanning confocal (CF) microscopy supported the capacity of AMP peptide to enhance accumulation of occludin and zonula occludens-1 in TJ domains of C2 cell monolayers and together with immunoblot analysis showed that the peptide protected against loss of these TJ proteins following oxidant injury. AMP peptide also protected against a fall in TER during disruption of actin filaments by cytochalasin D and stabilized perijunctional actin during oxidant injury when assessed by CF. These findings suggest that AMP-18 could protect the intestinal mucosal barrier by acting on specific TJ proteins and stabilizing perijunctional actin.
Cell Proliferation in the Developing Human Cerebral Cortex
Authors: Tiu Sau Cheung , Chan Wood Yee , Yew David T.
Published: June 2005

Cell proliferation or cell division has been considered a very important morphogenetic process during the development of the central nervous system. To determine the spatiotemporal pattern of proliferation in the developing human fetal brain, we used a specific antibody against the proliferation cell nuclear antigen (PCNA) and an immunohistochemical method to detect dividing cells in four neocortical regions, namely frontal, motor, occipital and temporal cortices, of human fetuses at different development stages (from 14 weeks to term). Positive cells were mostly found in the subcortical region of the neocortical regions at all the stages examined, although the developing cortical plate also occasionally showed scattered positive cells. Among the neocortical regions studied, the temporal cortex appeared to have the fewest positive cells, while the occipital cortex at 32 and 40 weeks contained the largest number of dividing cells. The PCNA immunoreactivity decreased rapidly with gestational age. The number of positive cells started to decrease early in the temporal cortex, from 14 weeks onwards, while in the motor and frontal cortices, a two-step decrease was seen between 14 and 21 weeks and between 27 and 32 weeks. In the occipital cortex, a decrease was also observed between 27 and 32 weeks, but only after an initial increase between 14 and 21 weeks. Our study thus clearly demonstrates specific patterns of regional as well as temporal distribution of dividing cells in the human fetal neocortex. Colocalization of PCNA with the glial fibrillary acidic protein and vimentin indicates that a majority of dividing cells are glial cells, especially toward late gestation.
Apoptosis – A Brief Review
Authors: Zhang Aiqun , Wu Yan , Lai Helen W.L. , Yew David. T.
Published: June 2005

Apoptosis is now recognized as an important process in different biological systems, including embryonic development, cell turnover, and immune response against tumorigenic or virus-infected cells. Under either physiological or pathological conditions, apoptosis is mostly driven by interactions among several families of protein, i.e. caspases, Bcl-2 family proteins, and inhibitor of apoptosis proteins (IAP). Other proteases such as granzyme B, calpain and cathepsin have also been demonstrated to play a vital role in apoptosis occurring under certain physiological states. This review focuses on the major apoptotic signaling pathways and the intracellular components involved in this process. Recent advances in our understanding of the role of apoptosis in neurodegenerative events and the clues they provide for the design of future preventive and therapeutic modalities will also be discussed.
Determination of the Levels of Anti-Thyroid-Stimulating Hormone Receptor Antibody with Thyroid Peroxidase Antibody in Omani Patients with Graves’ Disease
Authors: Alnaqdy Adel , Al-Maskari Masoud
Published: June 2005

Objective: To determine the levels of anti-thyroid-stimulating hormone receptor antibody (TRAb) and thyroid peroxidase antibodies (TPO) in Omani patients with Graves’ disease (GD). Subjects and Methods: ELISA was used to measure the levels of TRAb and TPO in sera of 111 patients with GD, 40 patients with systemic lupus erythematosus (SLE) and 50 healthy normal subjects. Seventy-eight GD patients received iodine-131 treatment while 33 newly diagnosed patients did not receive any treatment. Results: The levels of TRAb in the patients with GD, SLE and normal subjects were 7.24 9 ± 0.623, 1.04 ± 0.179 and 0.539 ± 0.070 units/liter, respectively. Elevated levels of TRAb were found in 75, 5 and 2% of patients with GD, SLE and normal subjects, respectively. For anti-TPO antibodies, the levels were 713.331 ± 97.905, 85.575 ± 34.936 and 22.96 ± 4.544 lU/ml, for patients with GD, SLE and normal subjects, respectively. The elevated level of anti-TPO antibodies were found in 72, 15 and 6% of patients with GD, SLE and normal subjects. Statistically significant differences in positive levels of TRAb and anti-TPO antibodies were found in patients with GD as compared to SLE and normal subjects (p < 0.001). The treated GD patients had lower levels of TRAb than untreated, but no difference was detected in the levels of anti-TPO antibodies between the treated and not treated. Conclusion: High levels of TRAb and TPO were detected in Omani patients with GD. TRAb may be helpful in the diagnosis and monitoring the efficacy of iodine-131 treatment in GD patients.
The Use of Locked Nails in the Treatment of Humeral Shaft: Delayed Union and Nonunion
Authors: Al Mukaimi Ali , Mokhtar Ahmed , Abo El Nass Mohamed
Published: June 2005

Objectives: To assess the results and clinical outcome of delayed union and nonunion humeral shaft treatment using locked medullary nails. Subjects and Methods: The Russel and Taylor humeral locking nail was used to treat 21 patients with humeral shaft fractures at Al Razi hospital, Kuwait, from 1997 to 2001. Of these, 8 had delayed union and 13 nonunion. Also, 13 had previous operative treatment, while 8 had nonoperative treatment. Antegrade nailing was done in all cases, and all nails were fixed statically. Autogenous iliac bone grafts were used in 17 cases. Results: Of the 21 cases of fractures, 19 were united. Only 2 cases had persistent nonunion. Eighteen cases had satisfactory shoulder function, and 3 lost shoulder abduction between 40 and 65 degrees. Conclusion: Our data showed that humeral locked nails can achieve satisfactory clinical results in treating humeral shaft delayed unions and nonunions.
Processes Involved in the Site-Specific Effect of Probucol on Atherosclerosis in Apolipoprotein E Gene Knockout Mice
Authors: Choy Katherine , Beck Konstanze , Png Francoise Y. , Wu Ben J. , Leichtweis Steven B. , Thomas Shane R. , Hou Jing Y. , Croft Kevin D. , Mori Trevor A. , Stocker Roland
Published: June 2005

Objective—

To elucidate processes by which the antioxidant probucol increases lesion size at the aortic sinus and decreases atherosclerosis at more distal sites in apolipoprotein E–deficient (apoE
−/−
) mice.

Methods and Results—

Male apoE
−/−
mice were fed high-fat chow with 1% (w/w) probucol or without (controls) for 6 months, before aortic sinus, arch, and descending aorta were analyzed separately for lesion size and composition. Compared with control, probucol significantly increased lesion size by 33% at the sinus, but it inhibited atherosclerosis at the descending aorta by 94%. Sites where atherosclerosis was inhibited contained substantially fewer macrophages, less lipids (cholesterol and cholesteryl esters), and endogenous antioxidant (α-tocopherol), but not oxidized lipids, and the extent to which probucol metabolism occurred was increased. Compared with control, aortic sinus lesions of probucol mice contained a substantially increased content of extracellular matrix, but decreased total cell and macrophage density, comparable levels of lipids and α-tocopherol, and decreased concentrations of oxidized lipids (cholesteryl ester hydroperoxides, F
2
-isoprostanes, and 7-ketocholesterol).

Conclusions—

Probucol affects atherosclerosis in apoE
−/−
mice independent of the accumulation of arterial lipid oxidation products, thereby dissociating the 2 processes. Rather, probucol exerts antiinflammatory activity by decreasing accumulation of macrophages in lesions, and it promotes a more stable lesion composition at the aortic sinus.
Differential effects of proteasome inhibition by bortezomib on murine acute graft-versus-host disease (GVHD): delayed administration of bortezomib results in increased GVHD-dependent gastrointestinal toxicity
Authors: Sun Kai , Wilkins Danice E. C. , Anver Miriam R. , Sayers Thomas J. , Panoskaltsis-Mortari Angela , Blazar Bruce R. , Welniak Lisbeth A. , Murphy William J.
Published: June 2005

We have recently demonstrated that the proteasome inhibitor, bortezomib, administered immediately following murine allogeneic bone marrow transplantation (BMT) resulted in marked inhibition of acute graft-versus-host disease (GVHD) with retention of graft-versus-tumor effects. We now assessed the effects of delayed bortezomib administration (5 or more days after BMT) on GVHD. Recipient C57BL/6 (H2b) mice were lethally irradiated and given transplants of bone marrow cells and splenocytes from major histocompatibility complex (MHC)–disparate BALB/c (H2d) donors. In marked contrast to the effects of bortezomib on GVHD prevention when administered immediately after BMT, delayed bortezomib administration resulted in significant acceleration of GVHD-dependent morbidity. No toxicity was observed following delayed bortezomib administration in models where donor T cells were not coadministered, indicating that these deleterious effects were critically dependent on GVHD induction. The increase in GVHD susceptibility even occurred when late administration of bortezomib was preceded by early administration. Pathologic assessment revealed that significant increases in gastrointestinal lesions occurred following delayed bortezomib administration during GVHD. This pathology correlated with significant increases of type 1 tumor necrosis factor α (TNF-α) receptor transcription in gastrointestinal cells and with significant increases of TNF-α, interleukin 1β (IL-1β), and IL-6 levels in the serum. These results indicate that the differential effects of proteasome inhibition with bortezomib on GVHD are critically dependent on the timing of bortezomib administration.
pSLIP: SVM based protein subcellular localization prediction using multiple physicochemical properties
Authors: Sarda Deepak , Chua Gek Huey , Li Kuo-Bin , Krishnan Arun
Published: June 2005

Background

Protein subcellular localization is an important determinant of protein function and hence, reliable methods for prediction of localization are needed. A number of prediction algorithms have been developed based on amino acid compositions or on the N-terminal characteristics (signal peptides) of proteins. However, such approaches lead to a loss of contextual information. Moreover, where information about the physicochemical properties of amino acids has been used, the methods employed to exploit that information are less than optimal and could use the information more effectively.

Results

In this paper, we propose a new algorithm called pSLIP which uses Support Vector Machines (SVMs) in conjunction with multiple physicochemical properties of amino acids to predict protein subcellular localization in eukaryotes across six different locations, namely, chloroplast, cytoplasmic, extracellular, mitochondrial, nuclear and plasma membrane. The algorithm was applied to the dataset provided by Park and Kanehisa and we obtained prediction accuracies for the different classes ranging from 87.7% – 97.0% with an overall accuracy of 93.1%.

Conclusion

This study presents a physicochemical property based protein localization prediction algorithm. Unlike other algorithms, contextual information is preserved by dividing the protein sequences into clusters. The prediction accuracy shows an improvement over other algorithms based on various types of amino acid composition (single, pair and gapped pair). We have also implemented a web server to predict protein localization across the six classes (available at http://pslip.bii.a-star.edu.sg/).
Can bile duct injuries be prevented? "A new technique in laparoscopic cholecystectomy"
Authors: Sari Yavuz Selim , Tunali Vahit , Tomaoglu Kamer , Karagöz Binnur , Güneyİ Ayhan , KaragöZ İbrahim
Published: June 2005

Background

Over the last decade, laparoscopic cholecystectomy has gained worldwide acceptance and considered to be as "gold standard" in the surgical management of symptomatic cholecystolithiasis. However, the incidence of bile duct injury in laparoscopic cholecystectomy is still two times greater compared to classic open surgery. The development of bile duct injury may result in biliary cirrhosis and increase in mortality rates. The mostly blamed causitive factor is the misidentification of the anatomy, especially by a surgeon who is at the beginning of his learning curve. Biliary tree injuries may be decreased by direct coloration of the cystic duct, ductus choledochus and even the gall bladder.

Methods

gall bladder fundus was punctured by Veress needle and all the bile was aspirated. The same amount of fifty percent methylene blue diluted by saline solution was injected into the gall bladder for coloration of biliary tree. The dissection of Calot triangle was much more safely performed after obtention of coloration of the gall bladder, cystic duct and choledocus.

Results

Between October 2003 and December 2004, overall 46 patients (of which 9 males) with a mean age of 47 (between 24 and 74) underwent laparoscopic cholecystectomy with methylene blue injection technique. The diagnosis of chronic cholecystitis (the thickness of the gall bladder wall was normal) confirmed by pre-operative abdominal ultrasonography in all patients. The diameters of the stones were greater than 1 centimeter in 32 patients and calcula of various sizes being smaller than 1 cm. were documented in 13 cases. One patient was operated for gall bladder polyp (our first case). Successful coloration of the gall bladder, cystic duct and ductus choledochus was possible in 43 patients, whereas only the gall bladder and proximal cystic duct were visualised in 3 cases. In these cases, ductus choledochus visibility was not possible. None of the patients developed bile duct injury.

Conclusion

The number of bile duct injuries related to anatomic misidentification can be decreased and even vanished by using intraoperative methylene blue injection technique into the gall bladder fundus intraoperatively.
An Inexpensive Gel Electrophoresis-Based Polymerase Chain Reaction Method for Quantifying mRNA Levels
Authors: Bradford William D. , Cahoon Laty , Freel Sara R. , Hoopes Laura L. Mays , Eckdahl Todd T.
Published: June 2005

In order to engage their students in a core methodology of the new genomics era, an everincreasing number of faculty at primarily undergraduate institutions are gaining access to microarray technology. Their students are conducting successful microarray experiments designed to address a variety of interesting questions. A next step in these teaching and research laboratory projects is often validation of the microarray data for individual selected genes. In the research community, this usually involves the use of real-time polymerase chain reaction (PCR), a technology that requires instrumentation and reagents that are prohibitively expensive for most undergraduate institutions. The results of a survey of faculty teaching undergraduates in classroom and research settings indicate a clear need for an alternative approach. We sought to develop an inexpensive and student-friendly gel electrophoresis-based PCR method for quantifying messenger RNA (mRNA) levels using undergraduate researchers as models for students in teaching and research laboratories. We compared the results for three selected genes measured by microarray analysis, real-time PCR, and the gel electrophoresis-based method. The data support the use of the gel electrophoresis-based method as an inexpensive, convenient, yet reliable alternative for quantifying mRNA levels in undergraduate laboratories.
Deleted Mitochondrial DNA in Human Luteinized Granulosa Cells
Authors: AU HENG‐KIEN , LIN SHYH‐HSIANG , HUANG SHIH‐YI , YEH TIEN‐SHUN , TZENG CHII‐RUEY , HSIEH RONG‐HONG
Published: June 2005

Abstract: The rearrangement of mitochondrial DNA in luteinized granulosa cells was determined in order to evaluate the fertilization capacity of oocytes and the development of embryos. Multiple deletions of mtDNA were found in luteinized granulosa cells from in vitro fertilization (IVF) patients. The 4977‐base pair (bp) deletion was the most frequent deletion found in human granulosa cells. No significant difference was noted between mtDNA deletions of granulosa cells based on the fertilization capacity of oocytes and the development of embryos. To determine the relationship of proportions of mtDNA rearrangements with the aging process, granulosa cells were grouped into three different cohorts according to maternal age: younger than 32 years, between 32 and 37 years, and older than 37 years. No statistical correlation was noted between patient age and the frequency of occurrence of multiple mtDNA deletions. However, an increase in granulosa cell apoptosis was associated with an increase in mtDNA deletions. Accumulation of mtDNA deletions may contribute to mitochondrial dysfunction and impaired ATP production. We concluded that the accumulation of rearranged mtDNA in granulosa cells might not interfere with fertilization of human oocytes and further embryonic development; it was, however, associated with apoptosis processes.
Oxidative Damage and Mitochondrial DNA Mutations with Endometriosis
Authors: KAO SHU‐HUEI , HUANG HSIENG‐CHIANG , HSIEH RONG‐HONG , CHEN SU‐CHEE , TSAI MING‐CHUAN , TZENG CHII‐REUY
Published: June 2005

Abstract: Endometriosis, a frequently encountered disease in gynecology, is a considerable threat to the physical, psychological, and social integrity of women. Moreover, up to 50% of infertile patients have this disease. The etiology and pathogenesis of this important disease are poorly understood; it is defined as an ectopic location for endometrium‐like glandular epithelium and stroma outside of the uterine cavity. It still remains an open question as to what extent the peritoneal environment influences the establishment and/or progression of endometriosis. As a result of such stress, a sterile, inflammatory reaction with the secretion of growth factors, cytokines, and chemokines is generated, which is especially deleterious to successful reproduction. Significantly higher amounts of oxidative damage were detected in endometriotic lesions than in controlled normal endometrium, including mitochondrial DNA (mtDNA) rearrangement, 8‐OH‐deoxyguanosine (8‐OH‐dG), and lipoperoxide contents. There were approximately sixfold increases in 8‐OH‐dG and lipoperoxides in chocolate cysts compared with normal endometrial tissues. A novel 5,335‐bp deletion of mtDNA was identified in endometriotic tissue. According to these results, we propose that oxidative stress and mtDNA mutations might be anticipated in the initiation or progression of endometriosis. Only by understanding the mechanisms involved in the pathogenesis of endometriosis can we develop a basis for new diagnostic and therapeutic approaches.
Oxidative Damage in Mitochondrial DNA Is Not Extensive
Authors: LIM KOK SEONG , JEYASEELAN KANDIAH , WHITEMAN MATTHEW , JENNER ANDREW , HALLIWELL BARRY
Published: June 2005

Abstract: Since 1988 several research groups have reported greater levels of oxidative damage in mitochondrial DNA than in nuclear DNA, while others have suggested that the greater damage in mtDNA might be due to artifactual oxidation. The popular theory that mtDNA is more heavily damaged in vivo than nDNA does not stand on firm ground. Using an improved GC‐MS method and pure mtDNA, our analyses revealed that the damage level in mtDNA is not higher, and may be somewhat lower, than that in nDNA.
2,6‐Diisopropylphenol Protects Osteoblasts from Oxidative Stress‐Induced Apoptosis through Suppression of Caspase‐3 Activation
Authors: CHEN RUEI‐MING , WU GONG‐JHE , CHANG HWA‐CHIA , CHEN JUE‐TAI , CHEN TZENG‐FU , LIN YI‐LING , CHEN TA‐LIANG
Published: June 2005

Abstract: 2,6‐Diisopropylphenol is an intravenous anesthetic agent used for induction and maintenance of anesthesia. Since it is similar to α‐tocopherol, 2,6‐diisopropylphenol may have antioxidant effects. Osteoblasts play important roles in bone remodeling. In this study, we attempted to evaluate the protective effects of 2,6‐diisopropylphenol on oxidative stress‐induced osteoblast insults and their possible mechanisms, using neonatal rat calvarial osteoblasts as the experimental model. Clinically relevant concentrations of 2,6‐diisopropylphenol (3 and 30 μM) had no effect on osteoblast viability. However, 2,6‐diisopropylphenol at 300 μM time‐dependently caused osteoblast death. Exposure to sodium nitroprusside (SNP), a nitric oxide donor, increased amounts of nitrite in osteoblasts. 2,6‐Diisopropylphenol did not scavenge basal or SNP‐releasing nitric oxide. Hydrogen peroxide (HP) enhanced levels of intracellular reactive oxygen species in osteoblasts. 2,6‐Diisopropylphenol significantly reduced HP‐induced oxidative stress. Exposure of osteoblasts to SNP and HP decreased cell viability time‐dependently. 2,6‐Diisopropylphenol protected osteoblasts from SNP‐ and HP‐induced cell damage. Analysis by a flow cytometric method revealed that SNP and HP induced osteoblast apoptosis. 2,6‐Diisopropylphenol significantly blocked SNP‐ and HP‐induced osteoblast apoptosis. Administration of SNP and HP increased caspase‐3 activities. However, 2,6‐diisopropylphenol significantly decreased SNP‐ and HP‐enhanced caspase‐3 activities. This study shows that a therapeutic concentration of 2,6‐diisopropylphenol can protect osteoblasts from SNP‐ and HP‐induced cell insults, possibly via suppression of caspase‐3 activities.
Improved Response in High-Risk Neuroblastoma With Protracted Topotecan Administration Using a Pharmacokinetically Guided Dosing Approach
Authors: Santana Victor M. , Furman Wayne L. , Billups Catherine A. , Hoffer Fredric , Davidoff Andrew M. , Houghton Peter J. , Stewart Clinton F.
Published: June 2005

Purpose

To estimate the response rate and toxicity associated with intravenous topotecan when it is administered on a protracted schedule according to a pharmacokinetically guided dosing approach to treat childhood high-risk neuroblastoma.

Patients and Methods

In this prospective phase II trial, topotecan was administered intravenously daily for 5 days for each of 2 consecutive weeks for two cycles. On the basis of topotecan systemic clearance, doses were individualized to attain a single-day topotecan lactone area under the plasma concentration-time curve (AUC) of 80 to 120 ng/mL · h. Patients subsequently received standard treatment.

Results

Both cycles were administered to 28 (93%) of the 30 enrolled patients (median age, 3.1 years). Target topotecan AUCs were achieved in 92 (72%) of the 127 measurements conducted after pharmacokinetically guided adjustment; the median dosage required to achieve target AUCs was 2.7 mg/m2 (range, 0.95 to 3.8 mg/m2). The response rate was 60% (95% CI, 41% to 77%); there were one complete and 17 partial responses. No patient experienced disease progression during initial topotecan therapy. Primary tumor volumes decreased (median decrease, −58.2%; range, −95.1% to −4.9%) in the 26 patients with available size data. Homovanillic acid levels in 16 (89%) of 18 patients and vanillylmandelic acid levels in 14 (78%) of 18 patients were lower (P = .002 and P = .018, respectively) after topotecan therapy. Reversible grade 4 myelosuppression occurred in all patients, but no deaths occurred as a result of infection or toxicity.

Conclusion

Topotecan is active against neuroblastoma when it is administered on a protracted schedule and targeted systemic exposure is achieved.
Randomized Trial of Neoadjuvant Chemotherapy Comparing Paclitaxel, Ifosfamide, and Cisplatin With Ifosfamide and Cisplatin Followed by Radical Surgery in Patients With Locally Advanced Squamous Cell Cervical Carcinoma: The SNAP01 (Studio Neo-Adjuvante Portio) Italian Collaborative Study
Authors: Buda Alessandro , Fossati Roldano , Colombo Nicoletta , Fei Francesca , Floriani Irene , Gueli Alletti Desiderio , Katsaros Dionyssios , Landoni Fabio , Lissoni Andrea , Malzoni Carmine , Sartori Enrico , Scollo Paolo , Torri Valter , Zola Paolo , Mangioni Costantino
Published: June 2005

Purpose

Neoadjuvant chemotherapy may represent an alternative to irradiation in locally advanced squamous cell cervical cancer. Aims of this study were to compare a three-drug (paclitaxel, ifosfamide, and cisplatin [TIP]) with a two-drug (ifosfamide and cisplatin [IP]) regimen and to assess the prognostic value of pathologic response on survival.

Patients and Methods

Patients (n = 219) were randomly assigned to ifosfamide 5 g/m2 during 24 hours plus cisplatin 75 mg/m2, or paclitaxel 175 mg/m2 plus ifosfamide 5 g/m2 during 24 hours and cisplatin 75 mg/m2 every 3 weeks for three courses.

Results

Grades 3 to 4 neutropenia, anemia, and thrombocytopenia were more frequent with TIP. We recorded four deaths related to toxicity. The optimal pathologic response (OPT) rate (residual disease < 3 mm stromal invasion) was higher with TIP than with IP (48% v 23%; odds ratio, 3.22; 95% CI, 1.69 to 5.88; P = .0003). At a median follow-up of 43.4 months, 79 women experienced disease progression or died (46 in the IP arm, 33 in the TIP arm). Patients receiving TIP experienced a treatment failure rate 25% less than those receiving IP, but this difference was not statistically significant (hazard ratio [HR], 0.75; 95% CI, 0.48 to 1.17; P = .20). Sixty-one patients died (37 in the IP arm, 24 in the TIP arm), and the HR of death was in favor of TIP, although not significantly (HR, 0.66; 95% CI, 0.39 to 1.10; P = .11). In patients assessable for response (n = 189), the average death rates were higher in the group that did not achieve OPT (HR, 5.88; 95% CI, 2.50 to 13.84; P < .0001).

Conclusion

The TIP regimen is associated with a higher response rate than the IP regimen, without a statistically significant effect on overall survival. OPT was a prognostic factor for survival.
Diagnosing Preclinical and Prodromal Neurodegenerative Diseases—The Clinical Is Political
Authors: Erickson Claire M. , Largent Emily A.
Published: February 2024

This Viewpoint describes clinical and political considerations for individuals diagnosed with neurodegenerative conditions during the preclinical or prodromal stage.
Segmented Acoustic Displays
Authors: Hardwick James , Subramanian Sriram , Plasencia Diego Martinez , Talamali Mohamed S.
Published: February 2024

For more than a century, segmented displays, such as the seven‐segment display, have been a popular and cost‐effective option. They can display various commonly used characters by controlling a few custom‐shaped binary light emitters. Herein, the acoustic equivalent of segmented displays, which uses heterogeneous sound modulators to generate a limited set of acoustic holographic images, is introduced. Designing segmented acoustic displays is more challenging than optical ones due to the complex relationship between emitted sound and generated holographic images. To address this challenge, a design methodology based on unsupervised learning techniques is proposed. The approach balances the cost of acoustic displays and the quality of the images they generate, resulting in segmented displays that outperform existing general‐purpose ones when generating a finite set of acoustic images. Using simulations and physical fabrication of metamaterial‐based acoustic displays, it is proven that the approach can create segmented acoustic displays that produce high‐quality images at a lower cost. Additionally, the methodology is applied to multifrequency acoustic displays and its scalability is assessed as the number of images increases. The cost reduction through segmentation presented herein is expected to democratize sound manipulators for acoustic displays and other applications like acoustic levitation and noise cancellation.