bluuebunny/crossref_metadata_2025_split huggingface dataset:
AMPA receptor subunit mRNAs and intracellular [Ca2+] in cultured mouse and rat cerebellar granule cells
Authors: Mogensen Helle S. , Jørgensen Ole Steen 
Published: July 2002

AbstractCultured mouse cerebellar granule cells differ from their rat counterparts in that they survive well when grown in non‐depolarising medium (5 mM K+). However, when chronically stimulated by added glutamate agonists, including (RS)α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA), rat cerebellar granule cells also survive well in non‐depolarising medium. We hypothesised that the relatively good survival of mouse cerebellar granule cells in the absence of added glutamate agonists might reflect AMPA receptors resistant to desensitisation. These receptors might be stimulated by endogenous glutamate. We tested this hypothesis by comparing cultured mouse and rat cerebellar granule cells grown in depolarising (25 mM K+) and non‐depolarising (5 mM K+) medium. We studied the AMPA‐induced increase in intracellular Ca2+ concentration ([Ca2+]i), using the fluorescent Ca2+ chelator, Fluo‐3, and the relative concentrations of mRNAs for the four AMPA receptor subunits, GluR1–4. GluR1–4 mRNAs were measured by restriction enzyme analysis of a PCR product containing cDNA with a composition proportional to the four subunit mRNAs. We found that the [Ca2+]i‐response to AMPA receptor activation in cultured cerebellar granule cells is determined mainly by the desensitisation properties of the AMPA receptors rather than by their ion permeability. We also found that mouse cerebellar granule cells express AMPA receptors which are more resistant to desensitisation than the corresponding rat AMPA receptors. Thus, relatively slow AMPA receptor desensitisation kinetics may contribute to the survival of mouse cerebellar granule cells in non‐depolarising medium.
High Cell Density Culture of Yarrowialipolytica Using a One‐Step Feeding Process
Authors: Kim Jie‐Wan , Park Tae Jung , Ryu Dewey D. Y. , Kim Jeong‐Yoon 
Published: July 2002

AbstractYarrowia lipolytica is a potentially useful host for heterologous protein production. To develop an efficient culture method for high cell density cultivation and heterologous gene expression of Y. lipolytica, the effects of medium components and their concentrations on the growth of Y. lipolytica have been investigated. Addition of yeast extract to the culture media was found to significantly reduce the long lag phase encountered when Y. lipolyticawas cultivated in synthetic culture media containing high concentrations of glycerol. Therefore, by enriching with 0.3% yeast extract the synthetic culture medium containing 15% glycerol, we could cultivate Y. lipolyticaup to 83 g/L dry cell weight in a batch culture. Furthermore, over 100 g/L and 88 units/mL of rice α‐amylase activity were obtained in less than 50 h with a one‐step feeding process in which a recombinant Y. lipolytica expressing rice α‐amylase was cultivated in the 10% glycerol medium enriched with 0.3% yeast extract and fed only once with the concentrated feeding medium (60% glycerol). The easy cultivation of recombinant Y. lipolytica to a high cell density may strengthen its position as a host for heterologous protein production.
Capillary Electrophoresis as a Method to Study DNA Reassociation
Authors: Li Yuanqian , White Jennifer , Stokes David , Sayler Gary , Sepaniak Michael 
Published: July 2002

AbstractTo develop analytical methodology to assess the genetic complexity of a DNA sample, capillary electrophoresis with laser‐induced fluorescence detection is used to monitor the annealing process of DNA samples. Coated columns are filled with an entangled polymer solution shown to optimally separate DNA through size‐selective capillary electrophoresis. DNA samples are denatured by heating in a boiling water bath for ∼10 min and then cooled to ∼25 °C below the melting point of the DNA sample to initiate the reassociation process. The DNA is detected by means of the laser‐induced fluorescence of intercalated ethidium bromide, which produces a substantially greater signal for double‐ versus single‐stranded DNA. The rate of reassociation is dependent upon the rate at which complimentary strands of DNA encounter each other and the degree of repeating base sequences in the sample (hence, the diversity of the DNA). Experimental parameters also influence the reassociation rate. The effects of salt concentration and incubation temperature are presented. Traditional plots of Cot (Co = DNA concentration and t = reassociation time) versus % recovery of double‐stranded DNA signal are generated for ΦX 174 Hae III digest and 50 bp stepladder DNA, individually and combined, to calculate the reassociation rate constants for these samples. Because reassociation of individual fragments is observed by the CE‐LIF method, more information about the samples is available than with less specific and time‐consuming traditional methods of investigating DNA reassociation.
Reproducibility of Pilot Scale Xanthan Fermentations
Authors: Amanullah Ashraf , Serrano Leobardo‐Carreon , Galindo Enrique , Nienow Alvin W. 
Published: July 2002

AbstractThe reproducibility of results is an essential prerequiste for a successful systematic analysis of the influence of process development parameters on fermentation performance. Concerns of inoculum inconsistency and strain instability in Xanthan fermentations have led to the use of a highly productive variant of Xanthomonas campestrisNRRL‐B1459 under strict preservation protocols and the development of an improved, yet simple inoculation strategy. This technique allows the propagation of standardized inocula, ensuring that starter cultures both identical in concentration and history are used. Implementation of this methodology resulted in extremely reproducible cultivations in shake flask and in fermenters of up to a pilot scale of 150 L in volume.
Reactive Extraction for Downstream Separation of 1,3‐Propanediol
Authors: Malinowski Janusz J. 
Published: July 2002

AbstractThe downstream separation of 1,3‐propanediol from dilute aqueous solution was studied. A process combining reversible reaction of 1,3‐propanediol with acetaldehyde to 2‐methyl‐1,3‐dioxane and a simultaneous extraction of the product by organic solvent appears to be technically feasible and attractive. The dioxane yield was 91−92%, the overall conversion of 1,3‐propanediol was ca. 98%, and recovery of dioxane into the organic extractant was 75%.
Keratinocytes from patients with lupus erythematosus show enhanced cytotoxicity to ultraviolet radiation and to antibody-mediated cytotoxicity
Authors: Furukawa F , Itoh T , Wakita H , Yagi H , Tokura Y , Norris D A , Takigawa M 
Published: July 2002

SUMMARYKeratinocyte cytotoxicity is an important component of the immunopathology of photosensitive lupus erythematosus, and antibody-dependent cell-mediated cytotoxicity (ADCC) has been shown to be an important mechanism by which autoantibodies, especially those specific for SS-A/Ro, can induce keratinocyte damage in models of photosensitive lupus. We provide further evidence that keratinocytes from patients with photosensitive lupus show significantly greater ultraviolet radiation (UVR)-induced cytotoxicity, and that ADCC of these targets is especially enhanced by autologous patient’s serum or by anti-SS-A/Ro+ sera. Keratinocytes from normal uninvolved skin of 29 patients with cutaneous lupus erythematosus (LE) were grown in cell culture and tested as targets in cytotoxicity experiments in vitro. Cultured keratinocytes from patients with systemic lupus erythematosus (SLE) and subacute cutaneous lupus erythematosus (SCLE) showed significantly greater cytotoxicity following UVR treatment than did keratinocytes from normal adult controls or from neonatal foreskins (P &lt; 0.01). The same cultures also showed greater UVR-induced binding of IgG from fractionated anti-SS-A/Ro+ preparations. ADCC experiments were also performed using keratinocytes cultured from patients with SLE, SCLE, discoid lupus erythematosus (DLE), and normal controls. When keratinocytes were incubated in autologous serum plus a standard mononuclear cell effector population, the percentage of ADCC observed was significantly greater in cultures containing keratinocytes and sera from the SLE and SCLE patients (P &lt; 0.001). When cultured keratinocytes were added to different IgG antibody probes, plus standard mononuclear effector populations, greater ADCC was seen using the anti-SS-A/Ro probe and keratinocytes from patients with SLE or SCLE. With normal human neonatal keratinocyte targets, the anti-SS-A/Ro probe induced greater ADCC than that seen with anti-ssDNA or normal human serum. We have shown that keratinocytes from patients with some forms of lupus erythematosus (SLE and SCLE) show greater cytotoxicity in vitro when irradiated with UVR, and greater susceptibility to ADCC whether the antibody source is their own serum or an anti-SS-A/Ro probe.
Plurihormonal pituitary adenomas: immunostaining of all pituitary hormones is mandatory for correct classification
Authors: Ho D M‐T , Hsu C‐Y , Ting L‐T , Chiang H 
Published: July 2002

Plurihormonal pituitary adenomas: immunostaining of all pituitary hormones is mandatory for correct classification Aims: We studied the clinicopathological characteristics of plurihormonal pituitary adenomas. Methods and results: The study material included 167 plurihormonal adenomas, which consisted of 31% of the surgically removed pituitary adenomas that we collected during a 12‐year period. The mean age of patients with plurihormonal adenoma was 45.7 years (range 13–75 years). There were 86 men and 81 women. All tumours were fully classified by immunohistochemical staining for seven pituitary hormones or subunits. Thirty immunohistochemical subtypes of plurihormonal adenomas were recognized. Hormonal symptoms were present in 70% of patients, while serum hormonal levels were increased in 89% of patients. Most patients had symptoms related to only one of the hormones and only 7% of patients had symptoms related to two hormones. The most common hormonal symptom was acromegaly (50%); symptoms related to hyperprolactinaemia ranked second (20%). Double immunostaining of all the possible combinations of the hormones was performed in 30 selected tumours, and they all showed mixtures of hormones in individual adenoma cells in any hormonal combinations studied. The latter finding supported the view that plurihormonal adenomas are monomorphous adenomas. Conclusions: Plurihormonal adenomas are common pituitary adenomas. Immunohistochemical staining of all pituitary hormones is mandatory for correct classification.
Stable isotopes indicate the extent of freshwater feeding by cormorants Phalacrocorax carbo shot at inland fisheries in England
Authors: Bearhop Stuart , Thompson David R. , Waldron Susan , Russell Ian. C. , Alexander Gavin , Furness Robert W. 
Published: July 2002

1. The numbers of cormorants Phalacrocorax carbo feeding at English freshwater fisheries during winter have increased rapidly over the last 20 years, causing concern among fishery managers and anglers. 2. In order to assess the extent of freshwater feeding, stable isotope ratios of carbon and nitrogen (δ13C and δ15N) in feathers of wild cormorants from inland freshwater fisheries were compared with those in the feathers of piscivorous birds with marine diets (captive ‘marine‐fed’ cormorants, free‐ranging shags Phalacrocorax aristotelis) and freshwater diets (juvenile goosanders Mergus merganser). 3. Isotope signatures of feathers represent the diet at the time of growth. Feathers grown at different times of the year were taken from wild cormorants; each feather type therefore represented the diet over a different temporal scale. 4. Isotopic analyses of feathers indicated that, when shot, nearly all of the cormorants had been feeding entirely on freshwater prey. The mean δ13C value of primary feathers growing when birds were shot was –22·2‰, indicative of an entirely freshwater diet. 5. The move to freshwater habitats from coastal breeding grounds occurred over several months, but once established cormorants appear to have fed at freshwater sites throughout the autumn and winter. 6. The suitability of using a two‐source isotopic mixing model in order to quantify the extent of freshwater feeding in piscivorous birds is discussed. 7. Although the results indicate long‐term residency and feeding in freshwater systems, they do not indicate whether birds were feeding regularly at the sites at which they were shot, or the composition of the diet. It is recommended that further studies using telemetry and multiple isotope analyses be carried out in order to address these issues.
Precision of Cavalieri sections and slices with local errors
Authors: CRUZ‐ORIVE L. M. 
Published: July 2002

SummaryCavalieri sections — and more recently Cavalieri slices, especially in combination with non‐invasive scanning — are widely used to estimate volumes. Physical Cavalieri slices are also increasingly used to estimate neuron numbers via the optical fractionator. In either case, the prediction of the error variance is important to assess optimal sample sizes. The error variance consists of two components, one due to the variation among the true contents of sections or slices, and the other due to local or ‘nugget’ errors. The latter may arise for instance when estimating section areas by point counting, or when counting discrete particles in slices or disectors. In this paper, a fairly comprehensive set of prediction formulae is presented to separate both variance components.
Management of diabetes in French prisons: a cross‐sectional study
Authors: Petit J. M. , Guenfoudi M. P. , Volatier S. , Rudoni S. , Vaillant G. , Hermant C. , Verges B. , Brun J. M. 
Published: July 2002

SUMMARY Aims  To assess by a survey the management of prisoners with diabetes treated with insulin in French prisons.Methods  A questionnaire was sent to the head of healthcare services for prisoners of every French prison. Information was obtained on prevalence of insulin‐treated diabetes prisoners and diabetes care in prison. The number of episides of ketoacidosis and hypoglycaemia needing hospital admissions were evaluated during the past year.Results  Among the 163 questionnaires sent, 115 were returned, giving an overall response rate of 69%. At the time of the study the prison population was 38 175 people. One hundred and sixty‐nine prisoners were treated by insulin (0.4%). Self‐monitoring of blood glucose was available only for 94 (55.6%) insulin‐treated prisoners. A total of 130 (76.9%) prisoners performed two insulin injections daily or less, 105 (62.1%) prisoners were not allowed to keep their insulin delivery systems with them. Of the prisoners who treated themselves, 14 (12.1%) used syringes and 42 (36.5%) used pen devices. Ninety‐two (55.1%) prisoners had had access to a diabetes specialist during the previous year. Diabetic diets were available in only 65 (60.7%) prisons. From June 1998 to June 1999, there were 20 hospital admissions for a diabetic ketoacidosis and 14 for hypoglycaemia.Conclusions  This study shows that prison decreases the autonomy of diabetic prisoners who often cannot self‐inject or test their blood. Access to visiting consultant diabetologists and specialist nurses to educate both prisoners with diabetes and prison staff could improve diabetic care.
Endovaginal Doppler ultrasound in ovarian torsion: a case series
Authors: Willms A. B. , Schlund J. F. , Meyer W. R. 
Published: July 2002

AbstractFour women with acute pelvic pain clinically suspected to be secondary to ovarian torsion were examined with gray‐scale and Doppler ultrasound. All affected ovaries were enlarged (volumes 3.2–34 times the volumes of the ovaries on the unaffected sides). Three ovaries showed no internal flow, and one showed internal arterial flow. Ovary‐conserving treatment was attempted in all four cases but the three ovaries which showed no evidence of internal flow eventually required removal. The fourth case, in which arterial flow was present on Doppler examination, was treated only with laparoscopic untwisting of the pedicle and did not require oophorectomy. The results of our study suggest that Doppler findings may distinguish ovaries which are beyond salvage and require removal from those which may be saved by prompt laparoscopic untwisting of the adnexa, but further studies with larger numbers of patients will be necessary. Copyright © 1995 International Society of Ultrasound in Obstetrics and Gynecology
Near vision, lags of accommodation and myopia
Authors: Charman W. N. 
Published: July 2002

SummaryIt is shown that, with some simplifying assumptions about the nature of the accommodation response/stimulus curve, geometrical optics predicts that lags in accommodation will result in ocular modulation transfer for any linear size of grating component in an object being independent of object distance. Thus bringing an object nearer to the eye should not improve the contrast of the retinal image of any of its details. However, when the effects of diffraction and aberration are considered, together with the angular spatial frequency dependence of the retinal contrast threshold, the expected advantages of short observation distances for the detection of fine detail emerge. It is shown that a reduced slope for the accommodation response/stimulus curve leads to increased lag and reduced modulation transfer: the possible role of such effects in the development of some types of myopia is discussed.
Pain and quality of life in patients with critical limb ischaemia: results of a randomized controlled multicentre study on the effect of spinal cord stimulation
Authors: Spincemaille G.H. , Klomp H.M. , Steyerberg E.W. , Habbema J.D.F. 
Published: July 2002

We carried out an assessment of pain and quality of life of patients with critical limb ischaemia during the follow‐up of a multicentre randomized trial in more detail than previously reported.In a multicentre clinical trial 120 patients were randomized between medical treatment and medical treatment plus spinal cord stimulation. Patients were selected on the basis of clinical symptoms and macrocirculatory data as described in the European consensus document on critical limb ischaemia. Data were collected at intake and then 1, 3, 6, 12 and 18 months later. Primary outcome measures were limb salvage, pain relief and quality of life. Patient and limb survival was estimated with the Kaplan–Meier method. Pain was evaluated using the visual analogue scale (VAS), the McGill pain questionnaire, the pain score of the Nottingham Health Profile (NHP) and the use of analgesics. Quality of life was evaluated using the NHP, the EuroQol and mobility subscore of the Sickness Impact Profile.The 2‐year limb survival was 52% for SCS treatment and 46% for standard treatment (p =0.47). Pain relief was considerable in both treatment strategies (p<0.005) with no significant differences between the strategies. The improvement occurred within the first few months and remained stable during further follow‐up. Patients with SCS used fewer non‐narcotic and narcotic drugs (p<0.001 at t=1 and t=3, p<0.002 at t=6). The overall scores of quality of life improved significantly (p<0.05), with no difference in score between treatments. The subscores of mobility and energy of the NHP in non‐amputated patients was significantly better in the SCS group (p<0.005). Amputation had a negative effect on mobility, resulting in a difficult rehabilitation but relieved pain substantially (p<0.05).In contrast to the existing literature, the randomized trial revealed no major difference in overall pain and quality of life assessment between treatment groups. The effect on energy and mobility was significantly better in patients treated with SCS, who also used substantially fewer analgesics.
Pressure-enhanced crystallization kinetics of amorphous Si and Ge: Implications for point-defect mechanisms
Authors: Lu Guo-Quan , Nygren Eric , Aziz Michael J. 
Published: July 2002

The effects of hydrostatic pressure on the solid-phase epitaxial growth (SPEG) rate v of intrinsic Ge(100) and undoped and doped Si(100) into their respective self-implanted amorphous phases are reported. Samples were annealed in a high-temperature, high-pressure diamond anvil cell. Cryogenically loaded fluid Ar, used as the pressure transmission medium, ensured a clean and hydrostatic environment. v was determined by in situ time-resolved visible (for Si) or infrared (for Ge) interferometry. v increased exponentially with pressure, characterized by a negative activation volume of −0.46Ω in Ge, where Ω is the atomic volume, and −0.28Ω in Si. The activation volume in Si is independent of both dopant concentration and dopant type. Structural relaxation of the amorphous phases has no significant effect on v. These and other results are inconsistent with all bulk point-defect mechanisms, but consistent with all interface point-defect mechanisms, proposed to date.
A kinetic analysis of the Spaepen–Turnbull interfacial dangling bond mechanism is presented, assuming thermal generation of dangling bonds at ledges along the interface, independent migration of the dangling bonds along the ledges to reconstruct the network from the amorphous to the crystalline structure, and unimolecular annihilation kinetics at dangling bond ‘‘traps.’’ The model yields v = 2 sin(θ)vsnr exp[(ΔSf + ΔSm)/k] exp− [(ΔHf + ΔHm)/kT], where ΔSf and ΔHf are the standard entropy and enthalpy of formation of a pair of dangling bonds, ΔSm and ΔHm are the entropy and enthalpy of motion of a dangling bond at the interface, vs is the speed of sound, θ is the misorientation from {111}, and nr is the net number of hops made by a dangling bond before it is annihilated. It accounts semiquantitatively for the measured prefactor, orientation dependence, activation energy, and activation volume of v, and the pressure of a ‘‘free-energy catastrophe’’ beyond which the exponential pressure enhancement of SPEG cannot continue uninterrupted due to a vanishing barrier to dangling bond migration. The enhancement of v by doping can be accounted for by an increased number of charged dangling bonds, with no change in the number of neutrals, at the interface. Quantitative models for the doping dependence of v are critically reviewed. At low concentrations the data can be accounted for by either the fractional ionization or the generalized Fermi-level-shifting models; methods to further test these models are enumerated. Ion irradiation may affect v by altering the populatio