bluuebunny/crossref_metadata_2025 huggingface dataset:
Staged Reconstruction for Malunited Fractures of the Distal Radius
Authors: EL-KAREF E.
Published: August 2004

This prospective study assessed the outcomes of 26 symptomatic malunited distal radial fractures which were treated with an opening wedge corrective osteotomy and bone grafting with rigid fixation. An ulnar shortening osteotomy was subsequently required as a second-stage operation in five cases to restore normal ulnar variance. A wrist arthroscopy was indicated as a third stage procedure with persistent ulnar sided wrist pain in order to address central tears of the triangular fibrocartilage.

Satisfactory functional scores were achieved by 20 of the 26 patients after distal radial osteotomy alone and, 24 of the 26 after subsequent ulnar shortening osteotomies and arthroscopy when necessary. The one, two or three stage concept of reconstructing the malunited distal end radius could optimise the outcome rather than using a single-stage strategy.
A Controlled Clinical Trial of Postoperative Hand Elevation at Home Following Day-Case Surgery
Authors: FAGAN D. J. , EVANS A. , GHANDOUR A. , PRABHKARAN P. , CLAY N. R. C.
Published: August 2004

Although elevation of the upper limb is considered valuable for the prevention and of the reduction of swelling following major surgery or severe injuries to the hand, it is not clear how much elevation, if any, is required following minor surgery such as carpal tunnel decompression. We investigated this by randomizing patients undergoing carpal tunnel decompression into two groups – one having high elevation at home and one being treated with a simple sling. Volumetric analysis of the swelling of the hand 5 days postoperatively showed no significant difference between the two groups. In the trial group, the mean increase in volume of the operated hand was 11 ml (95% CI +4 to +17) or 2.7%. In the control group, the mean swelling was 13 ml (95% CI +4 to +21) or 3.6%. The findings of this study do not support the use of routine high arm elevation following day-case surgery of the hand.
The Distal Radial Fracture in Elderly Women and the Bone Mineral Density of the Lumbar Spine and Hip
Authors: HEGEMAN J. H. , OSKAM J. , VAN DER PALEN J. , TEN DUIS H. J. , VIERHOUT P. A. M.
Published: August 2004

The incidence of distal radial fractures in elderly women is high and is associated with osteoporosis and hip fracture. Osteoporosis can be detected by measuring the bone mineral density (BMD) of the lumbar spine or hip with dual energy X-ray absorptiometry. Low BMD of the lumbar spine or hip is a strong predictor for future vertebral deformities and hip fractures. At present, elderly women with a distal radial fracture are not investigated for osteoporosis on a routine basis.

The BMD of the lumbar spine and hip were assessed in 94 women (mean age, 69 years) with a distal radial fracture. A low BMD was found in 85% of the patients, and osteoporosis was diagnosed in 51%. The mean BMD decreased by 0.04 SD per year and there was a significant relationship between post-menopausal status and decreased BMD of the hip. The BMD in patients treated with bisphosphonate medication increased significantly in 1 year. As more than half of the elderly women with a distal radial fracture have osteoporotic BMD values for the lumbar spine or hip, it is our opinion that such patients should be screened for osteoporosis.
An Isolated Ring Finger Metacarpal Shaft Fracture? – Beware An Associated Little Finger Carpometacarpal Joint Dislocation
Authors: CHONG ALPHONSUS K. S. , CHEW WINSTON Y. C.
Published: August 2004

Dislocations of the ulnar carpometacarpal joint are easily missed because of a low index of suspicion as well as their subtle clinical and radiological features. Often, the presence of a more obvious adjacent injury also draws attention away from the carpometacarpal joint. Two cases of ring finger metacarpal shaft fractures with associated little finger carpometacarpal joint dislocations are presented. In both cases, the metacarpal fractures were diagnosed but the carpometacarpal joint dislocations were initially overlooked. The presence of an apparently isolated ring finger metacarpal fracture due to an indirect force should raise the possibility of an associated carpometacarpal joint injury.
Strategic purchasing, supply management, and firm performance
Authors: Chen Injazz J. , Paulraj Antony , Lado Augustine A.
Published: August 2004

Purchasing has increasingly assumed a pivotal strategic role in supply‐chain management. Yet, claims of the strategic role of purchasing have not been fully subjected to rigorous theoretical and empirical scrutiny. Extant research has remained largely anecdotal and theoretically under‐developed. In this paper, we examine the links among strategic purchasing, supply management, and firm performance.

We argue that strategic purchasing can engender sustainable competitive advantage by enabling firms to: (a) foster close working relationships with a limited number of suppliers; (b) promote open communication among supply‐chain partners; and (c) develop long‐term strategic relationship orientation to achieve mutual gains. Using structural equation modeling, we empirically test a number of hypothesized relationships based on a sample of 221 United States manufacturing firms. Our results provide robust support for the links between strategic purchasing, supply management, customer responsiveness, and financial performance of the buying firm. Implications for future research and managerial practice in supply‐chain management are also offered.
Effect of selected wound antiseptics on adult articular cartilage (bovine sesamoid bone) in the presence ofEscherichia coliandStaphylococcus aureus
Authors: Müller Gerald , Kramer Axel
Published: August 2004

After removing an inoculum of 108–109cfu ofEscherichia coli (E. coli)orStaphylococcus aureus (S. aureus)effectively within 2 h from bovine sesamoid bones (bsb) using the iodophore Betaisodona® [0.5 and 1.0% (v/v) PVP‐I], the biguanide polihexanide (PHMB) [0.005 and 0.01% (v/v)], and the bispyridinamine Octenidine (Oct) [0.005 and 0.01% (v/v)] the metabolic effect on proteoglycans (PG) in bsb was investigated by subsequent culture of bsb for 7 d and biosynthetically labeling with35S‐sulfate for a period of 24 h.

The treatment with the iodophore stimulates the incorporation of35S‐sulfate into PG, whereas that of Oct was toxic. The PHMB treatment was both tolerated and effective only when it was used at low concentrations (0.005%). The antiseptic treatment did not result in an increase of catabolism of PG.

This in vitro study clearly demonstrates that irrigation of cartilage with an antiseptic should be limited to an effective concentration and treatment time compatible with antiseptic function. Iodophores have no negative feedback on cartilage metabolism, moreover, they stimulate chondrocytes in vitro. Cationic antiseptics are not suited as irrigating solutions. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
The effect of detachment of the articular cartilage from its calcified zone on the cartilage microstructure, assessed by 2H‐spectroscopic double quantum filtered MRI
Authors: Keinan‐Adamsky Keren , Shinar Hadassah , Navon Gil
Published: August 2004

Most studies on articular cartilage properties have been conducted after detachment of the cartilage from the bone. In the present work we investigated the effect of detachment on collagen fiber architecture. We used one‐dimensional 2 H double quantum filtered MRI on cartilage bone plugs equilibrated in deuterated saline. The quadrupolar splittings observed in the different zones were related to the degree of order and the density of the collagen fibers. The method is non‐destructive, allowing for measurements on the same plug without the need for fixation, dehydration, sectioning and decalcification. Detachment of the radial from the calcified zone resulted in swelling of the cartilage plug in physiological saline and a concomitant decrease in the quadrupolar splitting. The effect of mechanical pressure on the 2 H quadrupolar splittings for the detached cartilage and for the calcified zone‐bone plugs were compared with those of the same zones in the intact cartilage–bone plug. The splitting in the radial zone of the detached cartilage collapsed at much smaller loads compared to the intact cartilage–bone plug. The effect of the load on the size of the cartilage was also greater for the detached plug. These results indicate that anchoring of the cartilage to the bone through the calcified zone plays an important role in retaining the order of the collagen fibers. The water 2 H quadrupolar splitting in intact and proteoglycan‐depleted cartilage was the same, indicating that the proteoglycans do not contribute to the ordering of the collagen fibers. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Vegetation dynamics during the late Pleistocene in the Barreirinhas region, Maranhão State, northeastern Brazil, based on carbon Isotopes in soil organic matter
Authors: Pessenda Luiz Carlos Ruiz , Ribeiro Adauto de Souza , Gouveia Susy Eli Marques , Aravena Ramon , Boulet Rene , Bendassolli José Albertino
Published: August 2004

The study place is in the Barreirinhas region, Maranhão State, northeastern Brazil. A vegetation transect of 78 km was studied among four vegetation types: Restinga (coastal vegetation), Cerrado (woody savanna), Cerrad"o (dense woody savanna), and Forest, as well as three forested sites around Lagoa do Caçó, located approximately 10 km of the transect. Soil profiles in this transect were sampled for δ13C analysis, as well as buried charcoal fragments were used for 14C dating. The data interpretation indicated that approximately between 15,000 and ∽9000 14C yr B.P., arboreal vegetation prevailed in the whole transect, probably due to the presence of a humid climate. Approximately between ∽9000 and 4000–3000 14C yr B.P., there was the expansion of the savanna, probably related to the presence of drier climate. From ∽4000–3000 14C yr B.P. to the present, the results indicated an increase in the arboreal density in the area, due to the return to a more humid and probably similar climate to the present. The presence of buried charcoal fragments in several soil depths suggested the occurrence of palaeofires during the Holocene. The vegetation dynamic inferred in this study for northeastern Brazil is in agreement with the results obtained in areas of Amazon region, based on pollen analysis of lake sediments and carbon isotope analysis of soil organic matter (SOM), implying than similar climatic conditions have affected these areas during the late Pleistocene until the present.
Guest Editors' Preface: Workshop on Simulations of Ultra
Intense Laser Beams Interaction with Matter
Authors: Honrubia J. , Tikhonchuk V.
Published: August 2004

This issue of Laser and Particle Beams includes papers
presented at the “Workshop on Simulations of Ultra Intense Laser
Beams Interaction with Matter” held in Bordeaux, France, from 14
to 16 April, 2003. This workshop was organized jointly by the
Polytechnic University (Madrid, Spain), University of Bordeaux 1
(Talence, France), University of Milano-Bicocca (Milan, Italy), and
Commissariat à l'Energie Atomique (CEA, France), sponsored
by the European Science Foundation (ESF), University of Bordeaux 1, and
CEA.
Nonlocal electron heat transport and electron–ion energy
transfer in the presence of strong collisional heating
Authors: BIBI F. ALOUANI , MATTE J.-P.
Published: August 2004

Nonlocal electron heat transport in plasmas heated by a
high-intensity laser field is investigated. We show how the heat
transport is strongly modified by the super-Gaussian character of the
energy distribution caused by the strong collisional heating. The
change in the collisional electron–ion energy exchange due to
this modification of the shape of the electron distribution function is
also studied.
Progress in direct-drive fusion studies for the Laser
Mégajoule
Authors: CANAUD B. , FORTIN X. , GARAUDE F. , MEYER C. , PHILIPPE F.
Published: August 2004

In the context of the French Laser Mégajoule (LMJ) fusion
research program, direct drive is an alternate to indirect drive to
reach ignition and thermonuclear burn. We present recent progress in
the direct-drive fusion studies for LMJ. Calculations have shown that
the LMJ irradiation uniformity is characterized by long wavelength
asymmetries compatible with direct drive requirements. Calculations of
the irradiation uniformity in the context of indirect drive beam
positioning have been done. We show that non-uniformity can be
minimized by repointing the beams. Unfortunately, a time analysis shows
that this nonuniformity increases strongly in time above levels usually
considered inconsistent for direct drive. Finally, a recent baseline
target design is presented and consists of a DT ice shell surrounded by
a low-density CH foam wicked with cryogenic DT. This design can
potentially reach a gain of 90 with a 1-MJ on-target laser driver.
Hydrodynamic stability is increased at the ablation front and the
laser–target coupling efficiency achieves 85%.
Penetration of intense charged particle beams in the outer layers
of precompressed thermonuclear fuels
Authors: DEUTSCH C.
Published: August 2004

This paper emphasizes the energy dissipation through collective
electromagnetic modes (mostly transverse to the incoming beam) of
ultraintense relativistic electrons and nonrelativistic protons
interacting with a supercompressed core of deuterium + tritium (DT)
thermonuclear fuel. This pattern of beam–plasma interaction
documents the fast ignition scenario for inertial confinement
fusion.

The electronmagnetic Weibel instability is considered
analytically in a linear approximation. Relevant growth rates
parameters then highlight density ratios between target and particle
beams, as well as transverse temperatures. Significant refinements
include mode–mode couplings and collisions with target electrons.
The former qualify the so-called quasi-linear (weakly turbulent)
approach. Usually, it produces significantly lower growth rates than
the linear ones. Collisions enhance them slightly for
kc /ωp <
1, and dampen them strongly for kc
/ωp ≥ 1. Those results simplify rather
drastically for the laser-produced and nonrelativistic proton beams. In
this case, those growth rates remain always negative through a wide
range of beam–target parameters.
A hierarchy of nonlocal models for the radiative transfer equation
Authors: FEUGEAS J.-L.
Published: August 2004

For the classic diffusion description of radiative transfer, the
specific intensity can be represented by a small angular deviation of
the local Planckian equilibrium. In a transparent media, the angular
anisotropy becomes strong and one has to solve the general transfer
equation. We propose a hierarchy of models that can describe the regime
that lies between those two limits. Every member of this family is
hyperbolic, flux-limited, and possesses a locally dissipated entropy.
This hierarchy also formally recovers the diffusion limit. This study
demonstrates that the two-polynomial model is already capable of
capturing strong anisotropies.
Two-dimensional PIC simulation of atomic clusters in intense laser
fields
Authors: GRESCHIK F. , KULL H.-J.
Published: August 2004

Collective absorption of intense laser pulses by atomic clusters is
studied by PIC simulations. The cluster is modeled in two-dimensional
calculations as a cylindrical plasma column with a diameter of
D = 6.4 nm and an initial electron density of
ne0 = 1023
cm−3. The frequency and intensity dependence of
absorption is discussed. It is found that nonresonant absorption by
electron emission increases as a power law with the laser intensity.
The absorbed energy per electron reaches a maximum of about
Wmax =
mωp2D2
(ωp: plasma frequency, m: electron
mass) at the intensity where ionization saturates.
Numerical studies on the ultrashort pulseK-α emission sources based on femtosecond laser–target interactions
Authors: LIMPOUCH J. , KLIMO O. , BÍNA V. , KAWATA S.
Published: August 2004

K-α emission is an intense short-pulse line source well suited for X-ray diagnostic techniques with subpicosecond and micrometer resolution. Numerical simulations are performed here in a search for laser–target interaction regimes where both high efficiency of laser energy transformation to X-ray emission and ultrashort X-ray pulses are achieved. We use the one-dimensional PIC code for the description of the laser interaction with the plasma layer at the target surface. Fast electron transport into the target is treated by our newly developed Monte Carlo code with temporal resolution that is described here in detail. Our simulations reveal extremely short ∼200 fs FWHM brightK-α X-ray pulses emitted from targets heated by 120-fs pulses of a table-top laser. Laser energy conversion efficiency toK-α line emission as high as 6 × 10−5is noticed. Integration of the emitted energy over the focal spot is carried out to improve the simulation accord with published experimental data. Negligible impact of self-induced electric fields onK-α emission is found for conducting target materials at moderate laser intensities [lsim ]1017W/cm2.
One-dimensional model of the electrostatic ion acceleration in the
ultraintense laser–solid interaction
Authors: PASSONI M. , LONTANO M.
Published: August 2004

Effective ion acceleration of picosecond-duration well-collimated
bunches in the strong relativistic interaction of a short laser pulse
with a thin solid target has been experimentally demonstrated. In this
work, with reference to the sharp rear solid–vacuum interface,
where ion energization takes place, the one-dimensional
Poisson–Boltzmann equation is analytically solved on a finite
spatial interval whose extension is determined by requiring electron
energy conservation, resulting in the consistent spatial distributions
of the hot electrons created by the laser and of the corresponding
electrostatic potential. Then, the equation of motions for an ensemble
of test ions, initially distributed in a thin layer of the rear target
surface, with different initial conditions, is solved and the energy
spectrum corresponding to a given initial ion distribution is
determined.
Ion acceleration in overdense plasma by short laser pulse
Authors: SHOROKHOV O. , PUKHOV A.
Published: August 2004

We consider ion acceleration at the front surface of overdense plasma
by a short laser pulse. In this configuration, the laser ponderomotive
pressure pushes the background electrons, and a double layer is
produced at the boundary of the overdense region. The ions are
accelerated by the electrostatic field of the double layer. If the
laser intensity is so large that the plasma becomes relativistically
transparent, then ion trapping in the running double layer and
acceleration to relativistic energies is possible. We study this
physics using one-dimensional particle-in-cell simulations. Ion
acceleration in one- and two-component plasmas is considered. It is
shown that the proton acceleration is more effective when they
represent only a small dope to the heavy background ions.
Modeling of laser–plasma interaction on hydrodynamic scales:
Physics development and comparison with experiments
Authors: WEBER S. , RIAZUELO G. , MICHEL P. , LOUBÈRE R. , WALRAET F. , TIKHONCHUK V.T. , MALKA V. , OVADIA J. , BONNAUD G.
Published: August 2004

The forthcoming laser installations related to inertial confinement
fusion, Laser Mégajoule (LMJ) (France) and National Ignition
Facility (NIF) (USA), require multidimensional numerical simulation
tools for interpreting current experimental data and to perform
predictive modeling for future experiments. Simulations of macroscopic
plasma volumes of the order of 1 mm3 and laser exposure
times of the order of hundreds of picoseconds are necessary. We present
recent developments in the PARAX code towards this goal. The laser
field is treated in a standard paraxial approximation in three
dimensions. The plasma response is described by single-fluid,
two-temperature, fully nonlinear hydrodynamical equations in the plane
transverse to the laser propagation axis. The code also accounts for
the dominant nonlocal transport terms in spectral form originating from
a linearized solution to the Fokker–Planck equation. The
simulations of interest are hohlraum plasmas in the case of indirect
drive or the plasma corona for direct drive. Recent experimental
results on plasma-induced smoothing of RPP laser beams are used to
validate the code.
Lactic acidosis and developmental delay due to deficiency of E3 binding protein (protein X) of the pyruvate dehydrogenase complex
Authors: Ramadan D. G. , Head R. A. , Al‐Tawari A. , Habeeb Y. , Zaki M. , Al‐Ruqum F. , Besley G. T. N. , Wraith J. E. , Brown R. M. , Brown G. K.
Published: August 2004

Summary: Pyruvate dehydrogenase deficiency is an important cause of primary lactic acidosis. Most cases occur as a result of mutations in the gene for the E1α subunit of the complex, with a small number resulting from mutations in genes for other components, most commonly the E3 and E3‐binding protein subunits. We describe pyruvate dehydrogenase E3‐binding protein deficiency in two siblings in each of two unrelated families from Kuwait. The index patient in each family had reduced pyruvate dehydrogenase activity in cultured fibroblasts and no detectable immunoreactive E3‐binding protein. Both were homozygous for nonsense mutations in the E3‐binding protein gene, one involving the codon for glutamine 266, the other the codon for tryptophan 5.
New promoter mutations in the low‐density lipoprotein receptor gene which induce familial hypercholesterolaemia phenotype: Molecular and functional analysis
Authors: Francová H. , Trbušek M. , Zapletalová P. , Kuhrová V.
Published: August 2004

Summary: Low‐density lipoprotein receptor (LDLR) is a cell‐surface glycoprotein that mediates specific uptake and catabolism of plasma LDL. Mutations located in the coding region of the LDLR gene affect the structure and function of the protein and cause familial hypercholesterolaemia (FH). Mutations in the regulatory regions of the gene are rare, but in some cases have been shown to alter the transcriptional activity of the gene and cause the FH phenotype as well. Adult heterozygous FH individuals have a markedly raised plasma cholesterol that is associated with accelerated atherosclerosis and premature coronary heart disease. The aim of this study was the functional characterization of a promoter mutation in the LDLR gene in one family from the register of Czech FH subjects. Molecular screening revealed that three members of this family carried a ‐27C > T nucleotide transition in the promoter sequence (calculated from the start of transcription). All three manifested a heterozygous FH phenotype. This new mutation is located between the TATA box and sterol‐dependent regulatory element repeat 3. Using a luciferase reporter assay system, we analysed the transcriptional efficiency of the normal and mutant alleles. The mutation reduced promoter activity to background level. Another new promoter mutation ‐60C > T was identified in an unrelated patient in the conserved nucleotide sequence of the sterol‐dependent regulation element repeat 2 which virtually abolished the promoter activity. We assume a causal effect of this ‐60C > T transition on the basis of its position in the promoter sequence.
The third case of Doss porphyria (δ‐amino‐levulinic acid dehydratase deficiency) in Germany
Authors: Doss M. O. , Stauch T. , Gross U. , Renz M. , Akagi R. , Doss‐Frank M. , Seelig H. P. , Sassa S.
Published: August 2004

Summary:δ‐Aminolevulinic acid dehydratase (ALAD) deficiency porphyria, or Doss porphyria, was first reported in Germany in 1979. Only four bona fide cases of Doss porphyria have been reported to date that were confirmed by immunological and molecular analyses of their ALAD mutations. Here we describe the fifth case of Doss porphyria. A 17‐year‐old German male suffered from colicky abdominal pain and severe polyneuropathy for 2 years. Urinary δ‐aminolevulinic acid (ALA) was increased 32‐fold, and coproporphyrin 76‐fold compared with the upper limit of their respective normal ranges. Urinary excretion of porphobilinogen (PBG) and uroporphyrin was only slightly increased. Faecal porphyrins were within the normal range. Erythrocyte zinc protoporphyrin concentrations were elevated 5.4‐fold. ALAD activity in erythrocytes was decreased to 10% of the normal value, and was not activated by zinc and by dithiothreitol. Blood lead levels were within the normal range, excluding lead poisoning in the proband. Erythrocyte ALAD activity was about one‐half of the normal value in both parents, whereas it was normal in the proband's brother. Urinary excretion of ALA, PBG and total porphyrins was within the normal range in both parents and the brother. Molecular genetic studies of the ALAD gene in the proband revealed two base changes, C to A and C to T, both in intron 3 at ‐11 bp upstream of the exon 3 start site. In addition to the proband, the father carried the ‐11C‐to‐T, while the mother carried the ALAD gene in the proband's brother. These findings suggest that the observed compound heterozygosity of the ALAD gene may be responsible for Doss porphyria in the proband. The proband was successfully treated with haem arginate infusion. The clinical condition improved, and urinary excretion of ALA and coproporphyrin fell to levels of ~50% compared with their pretreatment levels during acute relapses. The haem therapy was continued once weekly for 1 year. At the end of 1 year, urinary ALA and porphyrin levels were significantly lowered, and the proband is now almost free of clinical symptoms.
Relief of gastrointestinal symptoms under enzyme replacement therapy in patients with Fabry disease
Authors: Dehout F. , Roland D. , de Granseigne S. Treille , Guillaume B. , Van Maldergem L.
Published: August 2004

Summary: Gastrointestinal symptoms, including diarrhoea and abdominal pain, are one of the earliest and most frequently reported signs of Fabry disease, a rare X‐linked lipid storage disorder. As the disease progresses, renal, cardiac and cerebrovascular complications develop, resulting in more serious symptoms and early mortality. The present study evaluated the effects of enzyme replacement therapy (ERT) with agalsidase alfa on the gastrointestinal symptoms ofFabry disease. Following 6 months of treatment, both the severity (p < 0.02) and frequency (p < 0.02) of abdominal pain decreased. For those patients who had received agalsidase alfa for more than 6 months, the observed improvement was generally maintained. This is the first study indicating a significant beneficial effect of ERT on gastrointestinal symptoms in a group of patients treated for Fabry disease.
Pseudo‐glutarylcarnitinaemia in medium‐chain acyl‐CoA dehydrogenase deficiency detected by tandem mass spectrometry newborn screening
Authors: Napolitano N. , Wiley V. , Pitt J. J.
Published: August 2004

Summary: As well as characteristic increases in C8 carnitine, dried blood spot samples from 11 newborns with medium‐chain acyl‐CoA dehydrogenase deficiency detected by tandem mass spectrometry screening using butyl esters showed apparent increases in glutarylcarnitine (m/z 388 signals). In four of the newborns in which it was measured, apparent increases in malonylcarnitine (m/z 360) were also detected. It was shown that the apparent increases were caused by interfering acylcarnitines, putatively identified as hydroxyoctanoylcarnitine and hydroxydecanoylcarnitine, respectively, using alternative derivatives for tandem mass spectrometry. Levels of the two abnormal carnitines correlated with C8 carnitine levels and normalized with repeat testing in 10 cases. These results indicated that the abnormal carnitines were significantly elevated only during periods of increased fatty acid catabolism, as may occur in the immediate postnatal period.
GTP‐cyclohydrolase I gene mutations in patients with autosomal dominant and recessive GTP‐CH1 deficiency: Identification and functional characterization of four novel mutations
Authors: Garavaglia B. , Invernizzi F. , Carbone M. L. Agostoni , Viscardi V. , Saracino F. , Ghezzi D. , Zeviani M. , Zorzi G. , Nardocci N.
Published: August 2004

Summary: GTP‐cyclohydrolase I (GTP‐CH1, EC 3.5.4.16) is encoded by the GCH1 gene. Mutations in the GCH1 gene cause both dopa‐responsive dystonia (McKusick 128230) and recessive GTP‐CH1 deficiency (McKusick 600225). The exact molecular mechanism resulting in decreased GTP‐CH1 activity in the patients is still obscure. We report the clinical features and molecular and functional study of the GCH1 gene in eight Italian patients affected by dominant and recessive GTP‐CH1 deficiency. All the studied patients had mutations in the GCH1 gene. Three missense mutations (V205G, K224R, P199A), a frameshift mutation (ΔG693), and a splice‐site mutation (ivs5 + 1g > c) were found. Except for K224R these are all novel mutations. To analyse the defect caused by the novel mutations, an in vivo functional assay in a Saccharomyces cerevisiae strain lacking the endogenous gene encoding GTP‐CH1 (FOL2) was performed. Complementation analysis showed that the ΔG693 and V205G mutations abolish the enzymatic function, while the P199A mutation causes a conditional defect. In conclusion, the clinical phenotypes displayed by our patients confirm the wide clinical spectrum of the disease and further support the lack of correlation between a given mutation and a clinical phenotype. Complementation analysis in yeast is a useful tool for confirming the pathogenetic effect of GCH1 mutations.
Efficiency of long‐term tetrahydrobiopterin monotherapy in phenylketonuria
Authors: Steinfeld R. , Kohlschütter A. , Ullrich K. , Lukacs Z.
Published: August 2004

Summary: Phenylketonuria, an inborn error of phenylalanine metabolism, occurs with a frequency of about 1 in 10 000 births and is treated with a strict dietary regimen. Recently, some patients with PKU have been found to show increased tolerance towards phenylalanine intake while receiving tetrahydrobiopterin (BH4) supplementation. We have treated two infants with BH4‐responsive PKU with BH4 for more than 2 years. No additional dietary control was required to maintain blood phenylalanine concentrations in the desired range. Both children have shown normal development. Generally, our results suggest that BH4 treatment might be an option for some patients with mild PKU, as it frees them from dietary restrictions and thus improves their quality of life.
Pseudo‐lysosomal storage disease caused by EMLA cream
Authors: Vallance H. , Chaba T. , Clarke L. , Taylor G.
Published: August 2004

Summary: Prilocaine–lidocaine emulsion (EMLA cream) is a topical anaesthetic commonly used prior to diagnostic and therapeutic procedures. While undergoing clinical investigation for the suspicion of a metabolic disorder, a series of children underwent skin biopsy with EMLA cream pretreatment. In each case, the pathologist identified ultrastructural features consistent with a lysosomal storage disorder, yet the clinical features were not consistent with the pathological findings. Ultrastructural artefact was suspected, resulting from the use of the EMLA cream. All patients underwent repeat skin biopsy without EMLA cream. Biopsies were reviewed by two pathologists blinded to the previous biopsy findings. Electron microscopy repeated without the use of EMLA cream was normal. It is concluded that the use of EMLA cream causes ultrastructural artefact and should be avoided prior to skin biopsy for electron microscopy.
The role of oxidative damage in the neuropathology of organic acidurias: Insights from animal studies
Authors: Wajner M. , Latini A. , Wyse A. T. S. , Dutra‐Filho C. S.
Published: August 2004

Summary: Organic acidurias represent a group of inherited disorders resulting from deficient activity of specific enzymes of the catabolism of amino acids, carbohydrates or lipids, leading to tissue accumulation of one or more carboxylic (organic) acids. Patients affected by organic acidurias predominantly present neurological symptoms and structural brain abnormalities, of which the aetiopathogenesis is poorly understood. However, in recent years increasing evidence has emerged suggesting that oxidative stress is possibly involved in the pathology of some organic acidurias and other inborn errors of metabolism. This review addresses some of the recent developments obtained mainly from animal studies indicating oxidative damage as an important determinant of the neuropathophysiology of some organic acidurias. Recent data showing that various organic acids are capable of inducing free radical generation and decreasing brain antioxidant defences is presented. The discussion focuses on the relatively low antioxidant defences of the brain and the vulnerability of this tissue to reactive species. This offers new perspectives for potential therapeutic strategies for these disorders, which may include the early use of appropriate antioxidants as a novel adjuvant therapy, besides the usual treatment based on removing toxic compounds and using special diets and pharmacological agents, such as cofactors and L‐carnitine.
Effect of high‐dose vitamins, coenzyme Q and high‐fat diet in paediatric patients with mitochondrial diseases
Authors: Panetta J. , Smith L. J. , Boneh A.
Published: August 2004

Summary: We reviewed the medical records of all patients with confirmed mitochondrial diseases treated with any or all of thiamin, riboflavin, coenzyme Q, vitamin C (~10 mg/kg per day) and a high‐fat diet (50–60% of caloric intake) between 1997 and 2003. There were 15 patients (9 male): 10 had enzymatic deficiency and 10 had a molecular diagnosis. Age at diagnosis was 11 months to 17 years 10 months. Treatment was commenced at time of clinical diagnosis in 12 patients. Follow‐up period was 3 days to 7 years (median 22 months). Improvement was reported in 9 patients, of whom 4 attained further developmental skills, but this was only temporary in 6 patients. Five patients died during the follow‐up period (3 days to 7 years). Patients with the 3243A > G mutation showed no significant change in the course of their disease, except for fewer migraine attacks. Of the six patients who had seizures, one has had a significant reduction in the severity of the seizures and one has had no further seizures. Plasma lactate levels were noncontributory. We conclude that high‐dose vitamin and cofactor treatment and, where applicable, high‐fat diet, are well tolerated and possibly effective in the short term, but ineffective in the longer term.
Successful pregnancy after combined renal–hepatic transplantation in glycogen storage disease type Ia
Authors: Lee P. J. , Muiesan P. , Heaton N.
Published: August 2004

Summary: Reports of liver and kidney transplantation and of pregnancy in glycogen storage disease type Ia (GSD Ia) (McKusick 232200) are rare. We report an individual who experienced all three successfully.
Kelley–Seegmiller syndrome due to a new variant of the hypoxanthine–guanine phosphoribosyltransferase (I136T) encoding gene (HPRT Marseille)
Authors: Dussol B. , Ceballos‐Picot I. , Aral B. , Castera V. , Philip N. , Berland Y.
Published: August 2004

Summary: A patient with hyperuricaemia and gouty arthritis due to a new variant of hypoxanthine–guanine phosphoribosyltransferase is described. The mutation (I136T, HPRT Marseille) is in the phosphoribosylpyrophosphate‐binding region of the gene and leads to almost total loss of enzyme activity in erythrocytes, with 5% in lymphocytes. Nevertheless, the patient showed no neurological abnormality.
The benefits of liver transplantation in glycogenosis type Ib
Authors: Bhattacharya K. , Heaton N. , Rela M. , Walter J. H. , Lee P. J.
Published: August 2004

Summary: There are few reports of liver transplantation in glycogenosis type Ib (GSD Ib). We present two cases who had dramatic catch‐up growth and reduced infections after transplantation, despite persistent neutropenia.
A compositional kinetic model of hydrate crystallization and dissolution
Authors: Cathles Lawrence M. , Chen Duo Fu
Published: August 2004

Hydrates are crystallizing near and at the seafloor from gas vents on shelves where the sedimentation rate is high and hydrocarbons are being generated. When seafloor temperature, vent rate, or vent gas composition changes, these hydrates may become unstable and decompose. We have constructed a compositional kinetic model of hydrate crystallization and dissolution that can address these issues. The model crystallizes hydrate in compositional bins and allows each to dissolve at either a kinetically or compositionally controlled rate if vent gas composition or temperature causes it to become unstable. We empirically calibrate the model to venting at the Bush Hill hydrate mound in the offshore Louisiana Gulf of Mexico, show how variations in venting rate crystallize hydrate of diverse composition in the subsurface, and investigate how bottom water temperature variations similar to those measured could increase the rate of gas venting by destabilizing hydrates within a few meters of the seafloor. We show that increases in bottom water temperature can cause gas venting rates to increase ∼100%, as suggested by recent measurements, only if the dissolution kinetics are fast compared to the empirically calibrated crystallization kinetics and dissolution gases are removed rapidly enough that they do not thermodynamically inhibit the rate of dissolution. Model characteristics required to further investigate hydrate mound construction are identified.
Methane in the western part of the Sea of Okhotsk in 1998–2000
Authors: Yoshida Osamu , Inoue Hisayuki Y. , Watanabe Shuichi , Noriki Shinichiro , Wakatsuchi Masaaki
Published: August 2004

We measured oceanic methane in the western part of the Sea of Okhotsk in 1998, 1999, and 2000. An anomalously high methane concentration was found in near‐bottom water above the shelfbreak (∼200 m) off northeast Sakhalin every year: up to 488 nmol kg−1 in 1998, 981 nmol kg−1 in 1999, and 556 nmol kg−1 in 2000. This anomalously high concentration can be used to trace the water with density range 26.6 to 26.8 σθ in the upper Dense Shelf Water. In the shelf off east Sakhalin, a strong stratification caused by freshwater from Amur River controlled the upward transport of methane through the suppression of vertical convection. The calculated methane flux was largest in the northeastern shelf region of Sakhalin (88 mol CH4 km−2 d−1). In the western part of the Sea of Okhotsk (0.73 × 106 km2, 51% of total Sea of Okhotsk area), the emission rate of methane was 11 Gg CH4 yr−1.
Effects of elevated CO2 and N fertilization on CH4 emissions from paddy rice fields
Authors: Xu Zhongjun , Zheng Xunhua , Wang Yuesi , Han Shenghui , Huang Yao , Zhu Jianguo , Butterbach‐Bahl Klaus
Published: August 2004

The authors employed free‐air carbon dioxide enrichment facilities for investigating the effects of elevating the present atmospheric CO2 by 200 μmol mol−1 and increasing the application rate of urea‐based fertilizers from 150 to 250 kg N ha−1 on CH4 emissions from paddy rice fields in southeastern China. The elevated CO2 significantly stimulated methane emission, which was mainly due to the stimulation in rice growth. Intensifying N fertilization mitigated the CH4 emission under the ambient CO2 but stimulated the CH4 emission under the elevated CO2. This suggests that N fertilization has a potential to stimulate both CH4 production and CH4 oxidation. Thus the net effect of N fertilization on CH4 emission from paddy rice fields most likely depends upon the counterbalance between the nitrogen‐induced increases in CH4 production and CH4 oxidation, as a N excess may result in the inhibition of methane emission, whereas a N limitation may result in the stimulation of methane emission.
Comparison of paleoclimatic change from Zr/Rb ratios in Chinese loess with marine isotope records over the 2.6–1.2 Ma BP interval
Authors: Liu Lianwen , Chen Jun , Ji Junfeng , Chen Yang
Published: August 2004

The loess‐paleosol sequences in north China act as a key archive in the study of continental paleoclimatic change over the last 2.6 Ma. However, the correlation between the continental loess records and the marine sediments over the 2.6–1.2 Ma BP interval is poorly studied. In this paper, Zr and Rb concentrations were measured on samples taken at 20 cm intervals from the Lingtai section over the interval from 2.6–1.2 Ma BP. Because Zr is enriched in coarse grain fractions whereas Rb is enriched in the fine fractions which are retained during loess pedogenesis, the Zr/Rb in loess can reflect the original grain size variation and serve as a proxy for winter monsoon strength. Our Zr/Rb ratios over the interval from 2.6–1.2 Ma BP generally match the marine δ18O record, especially during the 1.9–1.2 Ma BP interval. Strong 400 ka periodicity cycles found in the loess Zr/Rb ratio record are similar to the marine δ13C record, suggesting a possible low latitude influence on the paleoclimatic regime during this interval.
Plasmapause undulation of 17 April 2002
Authors: Goldstein J. , Sandel B. R. , Hairston M. R. , Mende S. B.
Published: August 2004

We report IMAGE EUV observations of a striking undulatory motion of the plasmapause that occurred on 17 April 2002, in which a large ripple propagated westward across the duskside plasmapause. From the plasmapause motion we infer a peak E‐field of ≈3 mV/m associated with the undulation, and estimate the undulation's equatorial azimuthal speed to be 0.9 rad/hr ≈ 4 RE/hr, corresponding to ≈1 km/s in the ionosphere (using an R3/2 dependence to map from the equator). Because DMSP ion drift data at 850 km altitude show the presence of a subauroral polarization stream (SAPS) flow channel ≈1 km/s at the same location and time as the undulation, we assert that SAPS was responsible for removal of plasma during the undulation. The SAPS apparently formed in response to a 19:00 UT substorm onset.
Large amplitude, extremely rapid, predominantly perpendicular electric field structures at the magnetopause
Authors: Mozer F. S. , Bale S. D. , Scudder J. D.
Published: August 2004

Electric fields with amplitudes to 140 mV/m and average durations of 7.5 milliseconds have been observed at the magnetospheric side of the dayside magnetopause. These fields are predominantly perpendicular to B, they are electrostatic, and they occur inside local minima in the plasma density. Because they have been observed at each of approximately seven opportunities, they must be a common feature of the magnetopause. They may be associated with the magnetospheric separatrix because computer simulations suggest such structures. Their complete characterization requires time domain measurements of plasma and three component fields with better than a few millisecond time resolution.
Lateral variation of the D″ discontinuity beneath the Cocos Plate
Authors: Lay T. , Garnero E. J. , Russell S. A.
Published: August 2004

Broadband shear wave signals from 15 deep South American earthquakes reveal small‐scale variations of the D″ shear velocity discontinuity beneath the Cocos Plate. Deconvolution by average event source wavelets allows multiple event and California station combinations to be double‐array stacked in 4 geographically separate reflection point bins with lateral dimensions of about 200 km. Reflections from the top of D″ are apparent in all 4 bins, with significant variations in timing and strength relative to ScS. The data are compatible with a discontinuous shear velocity increase 264 km above the core‐mantle boundary that varies laterally in strength from 0.9% to 2.6%, with corresponding lateral velocity variations within D″.
Linkages between coastal runoff and the Florida Keys ecosystem: A study of a dark plume event
Authors: Hu Chuanmin , Muller‐Karger Frank E. , Vargo Gabriel A. , Neely Merrie Beth , Johns Elizabeth
Published: August 2004

Using data collected by satellite sensors, rain and river gauges, and ship surveys, we studied the development and wind‐driven transport of a dark water plume from near Charlotte Harbor, Florida, to the Dry Tortugas in the Florida Keys in mid‐October 2003. MODIS and SeaWiFS imagery showed that the patch contained an extensive (∼5,500 km2) phytoplankton bloom that formed originally near the central coast of Florida. The data linked the bloom to high nutrient coastal runoff caused by heavy rainfall in June and August. Total N and P required for the bloom, which may contain some Karenia brevis cells, was estimated to be 2.3 × 107 and 1.5 × 106 moles, respectively. The dark color became increasingly dominated by colored dissolved organic matter, toward the Dry Tortugas, where CDOM absorption coefficients (0.08–0.12 m−1 at 400 nm) were 2–3 times higher than the surrounding shelf waters, while chlorophyll and inorganic nutrients decreased to negligible levels.
Comment on “The effect of velocity structure errors on double‐difference earthquake location” by A. Michelini and A. Lomax
Authors: Thurber Clifford , Zhang Haijiang
Published: August 2004

Michelini and Lomax [2004] (hereinafter ML2004) make some statements regarding the double‐difference (DD) tomography method of Zhang and Thurber [2003] (hereinafter ZT2003) that are incorrect or misleading. In this comment, we indicate the ways in which ML2004 misrepresent characteristics of ZT2003's DD tomography algorithm and the associated code tomoDD. In the process, we clarify the ways in which tomoDD differs from the DD location code hypoDD of Waldhauser [2001] and Waldhauser and Ellsworth [2000] (hereinafter WE2000).
Nonparametric direct mapping of rainfall‐runoff relationships: An alternative approach to data analysis and modeling?
Authors: Iorgulescu I. , Beven K. J.
Published: August 2004

We present a new approach for the analysis and modeling of catchment rainfall‐runoff relationships that uses as predictor variables input history summary variables only. The latter are defined as linear combinations of inputs at a given number of previous time steps. This transforms the dynamic identification problem into a static one. As the identification algorithm we use regression trees, which act as a nonlinear nonparametric model. The original algorithm is adapted to account for serial correlation in variables. The new method is applied to two subcatchments of the U.S. Department of Agriculture Forest Service Andrews Experimental Forest Watershed (Oregon, United States). Simple and interpretable tree models explain more than 80% of the initial deviance of the observations in both calibration and validation. This suggests that the selected variables have a good predictive power and that further modeling attempts using them are warranted. The models show a distinct pattern of the selected explanatory variables. Applications of the method include data quality control, comparative analysis, assessment of hydrological change, and multicriterion evaluation of parametric hydrological models.