bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and characterization of near‐isogenic lines of sorghum segregating for glycinebetaine accumulation
Authors: Mickelbart Michael V. , Peel Gregory , Joly Robert J. , Rhodes David , Ejeta Gebisa , Goldsbrough Peter B.
Published: May 2003

Glycinebetaine (GB) is a compatible solute synthesized by species in a number of plant families, including some grasses such as sorghum (Sorghum bicolor L. Moench). A recombinant‐inbred (RI) population was developed from a cross between GB‐deficient (IS2319) and GB‐accumulating (P932296) sorghum genotypes. The proportions of GB‐accumulating lines in both the F5 and F7:8 generations of this RI population were higher than expected, possibly due to some beneficial effect of GB accumulation on plant growth, survival or seed set. GB levels varied widely in lines of the RI population that were grown under controlled conditions, suggesting genetic control not only for the presence or absence of GB, but also for the level of GB. This hypothesis was tested by analysing individual plants from lines identified as accumulating low, medium or high concentrations of GB based on the F5 and F7:8 screens. The level of GB was conserved within lines, supporting the hypothesis of genetic control of relative GB levels within accumulating lines. Two pairs of near‐isogenic lines (NILs) with contrasting GB levels within pairs were developed from the RI population. The stable inheritance of the GB phenotype and isogenicity of these NILs were confirmed with progeny tests and molecular marker analysis, respectively. Labelling studies demonstrated that the deficiency in GB accumulation was at the choline oxidation step.
Transfer of florigenic stimuli between tillers in photoperiodically split plants of Dactylis glomerata and Bromus inermis
Authors: Havstad Lars T. , Aamlid Trygve S. , Heide Ola M. , Junttila Olavi
Published: May 2003

The flowering response was studied in single plants of Dactylis glomerata cv. Apelsvoll and Bromus inermis cv. Løfar, with one half exposed to inductive short days (SD = 8 h) and the other half exposed to non‐inductive long days (LD = 24 h) during primary induction in a daylength tunnel. Although unsplit control plants of D. glomerata showed an absolute SD requirement for primary induction, 38% of the LD‐treated half‐plants headed if the opposite half‐plant had been exposed to SD. In B. inermis SD‐exposure of one side resulted in a 5‐fold increase in panicle production on the opposite LD side. These data suggest that flowering stimuli can be translocated from one tiller to another in these short–long day grasses, but it remains to be established whether this transport is specific or merely a result of carbohydrate flow to the LD sink of the photoperiodically split plants. Since LD exposure of the opposite half‐plant had relatively little influence on percent heading or panicle number on the SD side, the translocation of flowering inhibitors appeared to be more limited than that of flowering stimuli. A preliminary experiment using radiolabelled gibberellin confirmed that intertiller translocation of this primary induction inhibitor was virtually absent in D. glomerata and only amounted to 10–15% of the applied radioactivity in B. inermis. Although the specific roles of flowering stimuli and flowering inhibitors, including various gibberellins, remain to be elucidated, these data help to explain why it is often observed that late‐emerging tillers, which have not been directly exposed to inductive conditions of sufficient duration, become reproductive in these grasses.
Optic nerve hypoplasia in cholestatic infants: a multiple case study
Authors: Fahnehjelm Kristina Teär , Fischler Björn , Jacobson Lena , Nemeth Antal
Published: May 2003

Purpose:  To present four infants with optic nerve hypoplasia and cholestasis.

Methods:  All patients underwent detailed ophthalmological and hepatological assessment. Their endocrinological and neuroradiological examinations were re‐evaluated.

Results:  All four infants presented with cholestasis and were subsequently found to have optic nerve hypoplasia. One child was blind according to the WHO definition and two had low vision. The fourth child had unilateral optic nerve hypoplasia and was too young to be assessed with optotypes. All four children had central nervous system and/or endocrine dysfunction. However, only one child had septo‐optic dysplasia. The longterm outcome of liver disease seemed favourable in all children.

Conclusion:  Early assessment by a paediatric ophthalmologist as well as a multidisciplinary approach is of great importance in cholestatic infants.
A new technique for removing the inner wall of Schlemm's canal using cyanoacrylate
Authors: Naruse Shigeta , Mori Kazuhiko , Kinoshita Shigeru
Published: May 2003

Purpose:  To introduce a new technique for removing the inner wall of Schlemm's canal using cyanoacrylate.

Methods:  Two donor eyes were used in this study. A limbal‐based scleral flap was dissected. The external wall of Schlemm's canal was opened and the inner wall of Schlemm's canal was exposed. Ethyl‐2‐cyanoacrylate was applied uniformly to the inner wall. After it had solidified, it was removed with fine forceps. The operated sites were then studied by light microscopy.

Results:  After cyanoacrylate removal, the aqueous humour was seen percolating through the thin remaining trabecular meshwork. Histopathological findings at the operated sites revealed that the lining of the Schlemm's endothelial cells was irregular. Endothelial cell nuclei were rarely seen along the canal wall. Microperforation to the anterior chamber was not seen.

Conclusion:  This new technique is potentially a safer method for removing the inner wall of Schlemm's canal than the conventional method.
Transpupillary thermotherapy of predominantly occult choroidal neovascularization in age‐related macular degeneration with 12 months follow‐up
Authors: Algvere Peep V. , Libert Carina , Lindgärde Gunnar , Seregard Stefan
Published: May 2003

Purpose:  To perform a phase I/II safety and efficacy study in order to assess the outcome following transpupillary thermotherapy (TTT) for occult choroidal neovascularization (CNV) with no or minimally classic CNV in age‐related macular degeneration.

Methods:  The study comprised 113 referred patients (79 females, 34 males) aged 59–89 years (mean 77.7 years) with predominantly occult CNV. There were 49 cases of occult with no classic CNV and 64 of occult with minimally classic CNV. According to their greatest linear dimension, lesions were classified as being < 3.0 mm or > 3.0 mm. Transpupillary thermotherapy was delivered with a diode laser, emission at 810 nm, duration 60 seconds, laser power 500–800 mW. Clinical examination, ETDRS logMAR visual acuity and fluorescein angiography were carried out at baseline, and at 3, 6 and 12 months in all cases.

Results:  The average baseline visual acuity was 0.20 (50.6 letters). Following TTT, it was 0.12 (42.0 letters) at 6 months and 0.12 (38.0 letters) at 12 months. Visual acuity improved in 9/113 eyes (8.0%), remained unchanged in 46 (40.7%) eyes, and deteriorated in 58 (51.3%) eyes. There was no significant difference in the proportion of eyes that had lost at least 15 letters at 12 months in the subgroup of occult with no classic CNV (18/49; 36.7%) versus those with minimally classic lesions < 3.0 mm (15/39; 38.5%). However, 13/25 (52.0%) of cases with minimally classic lesions > 3.0 mm had lost at least 15 letters at 12 months (p = 0.31). The most common complications in the 46 eyes that suffered visual loss comprised subretinal progressive fibrosis (18 eyes) and atrophy of the retinal pigment epithelium (13 eyes).

Conclusions:  This study shows that TTT generally prevents moderate and severe visual loss at 12 months follow‐up in occult CNV with no classic CNV. Eyes with minimally classic lesions with a greatest linear dimension of < 3.0 mm also show the same positive outcome. These results compare favourably with published data on the natural course of the disease. However, minimally classic lesions of > 3.0 mm responded poorly in this treatment setting.
Telemedicine in ophthalmology
Authors: Lamminen Heikki , Voipio Ville , Ruohonen Keijo , Uusitalo Hannu
Published: May 2003

Objectives:  To give an overview of telemedical applications in ophthalmology and to provide background information on new tele‐ophthalmological applications.

Methods:  We carried out a literature review, a database search and an Internet search.

Results:  According to published research, the cost‐efficiency of telemedicine in ophthalmology has not been established. It has been found to have educational benefits and patients have been satisfied with the possibility of obtaining specialist care without having to travel.

Conclusions:  Most studies have been pilot studies and telemedicine is still seldom the primary mode of operation. Technical problems have not been significant, but many open questions about organizational and operational issues remain. Further studies should be directed towards solving these problems and establishing technical standards.
Caspases and T lymphocytes: a flip of the coin?
Authors: Lakhani Saquib , Flavell Richard A.
Published: May 2003

Summary:  In this review, we consider the role caspases play in cell death downstream of death receptors and cell intrinsic death mechanisms. In particular, we focus on these mechanisms in antigen‐induced cell death, a mechanism which regulates the number of surviving T cells at the end of an immune response. The relative role of the apoptosome as an amplifier rather than an initiator of apoptosis is considered. Several factors that regulate the susceptibility to activation‐induced cell death are considered. These factors emanate from the stimulation of the T‐cell receptors and include multiple pathways. Recent work has shown that death receptor signaling can play an interesting role in cell proliferation in both humans and animals. These recent findings are discussed in the light of models of death receptor signaling.
Mitochondrial volume densities in the smokeless tobacco‐treated hamster cheek pouch epithelium
Authors: Alonge OK , Ashrafi SH , Colvard MD
Published: May 2003

OBJECTIVES: To compare the morphological changes and quantitative distribution of mitochondria in the hamster cheek pouch (HCP) epithelium treated with smokeless tobacco (ST).

MATERIALS AND METHODS: Archives of experimental material from previously published studies (Ashrafi et al., 1992) were utilized. Animals in experimental group received moist ST (snuff) in their right pouch, 5 days weekly for 24 months, while no snuff was given to control group. After 24 months, the epithelial tissues were processed for electron microscopy study. Volume densities of mitochondria were assessed by morphometry.

MAIN OUTCOME MEASURES: Mitochondrial volume densities in the two groups, experimental vs control.

RESULTS: In both control and experimental groups mitochondria were concentrated between the nucleus and basal cell plasma membrane. A decrease in the mean mitochondrial volume density (Vvmit) was observed from the basal layer to the more superficial layers in both groups. The experimental HCP displayed more mitochondria than control, and the granular epithelial cell layer in experimental group showed significantly a higher mean Vvmit than the control group (P = 0.03). It was concluded that greater numbers of mitochondria were retained in ST‐treated granular cells of the hyperplastic epithelia than in the normal epithelium.
In vitro effect of platelet‐derived growth factor‐BB on collagen synthesis and proliferation of human periodontal ligament cells
Authors: Ojima Y , Mizuno M , Kuboki Y , Komori T
Published: May 2003

OBJECTIVES: Platelet‐derived growth factor (PDGF)‐BB is a polypeptide growth factor which has been shown to stimulate periodontal regeneration. In this study, we investigated the time‐ and dose‐dependent effect of PDGF‐BB on the proliferation and collagen synthesis of human periodontal ligament (PDL) cells.

MATERIALS AND METHODS: For the proliferation assay, PDL cells were cultured in 0.01–10 ng ml−1 of PDGF‐BB for 12 or 24 h, and cell numbers were counted. For the collagen synthesis assay, PDL cells were cultured in 0.1–10 ng ml−1 of PDGF‐BB for 1 to 24 h. The ratio of collagen content in total protein was evaluated, and the gene expression of type I collagen was assessed quantitatively by Northern blotting analysis.

RESULT AND CONCLUSIONS: PDGF‐BB stimulated the proliferation of PDL cells in a time‐ and dose‐dependent manner with the maximum effect at 10 ng ml−1. PDGF‐BB induced the collagen synthesis of PDL cells with the maximum effect for 24‐h treatment, and 1 ng ml−1 of PDGF‐BB. PDGF‐BB exhibits an inverse dose‐dependent effect on proliferation and collagen synthesis by PDL cells. These findings suggest that PDGF‐BB is one of the important regulators of the maintenance of the extracellular matrix in PDL, and may play an important role in the regeneration of PDL.
The effects of six months of treatment with a low‐dose of conjugated oestrogens in menopausal women
Authors: Schlegel W. , Petersdorf L. I. , Junker R. , Schulte H. , Ebert C. , Von Eckardstein A.
Published: May 2003

OBJECTIVE

Hormone replacement therapy (HRT) is usually prescribed as medium‐ to high‐dose formulations. Little is known, however, about dose‐dependency of oestrogen effects on plasma hormone levels, markers of cardiovascular risk in lipid metabolism and the haemostatic system, or markers of bone turnover.

SUBJECTS AND DESIGN

In an open trial, three groups of 12 or 13 healthy, non‐obese postmenopausal women received conjugated equine oestrogens (CEE) for 6 months at doses of 0.3 mg/day (group 1), 0.6 mg/day (group 2) or 1.25 mg/day (group 3). From day 1 to day 10, CEE was administered alone, and from day 11 to day 21, in combination with 5 mg of medrogestone. Each treatment cycle was followed by a pause of 7 days. Fasting blood samples were obtained before treatment as well as on days 10, 21 and 28 of the first, third and sixth months on treatment. All results obtained on day 10 were grouped together as phase A, on day 21 as phase B, and on day 28 as phase C.

MEASUREMENTS

Plasma concentrations of oestradiol (E), dehydroepiandrosterone sulphate (DHEA‐S), total testosterone (T), FSH, PRL, sex hormone binding globulin (SHBG), type I procollagen propeptide (PICP) and the cross‐linked carboxyterminal telopeptide of type I collagen (ICTP), total cholesterol, HDL‐cholesterol, triglycerides (TG), apolipoprotein (apo) A‐1, apo B, lipoprotein(a)[Lp (a)], fibrinogen, factor VIIc and plasminogen activator inhibitor 1 (PAI‐1) were evaluated with commercially available kits.

RESULTS

Dose‐dependently, the three regimens increased E, SHBG and factor VIIc activity and decreased FSH, DHEAS, cholesterol, LDL‐cholesterol and apoB. HDL‐cholesterol and apoA‐1 were slightly decreased in group 1 but increased in groups 2 and 3. The high CEE dosage in group 3 resulted in a significant increase of TG and decrease of Lp(a) and PAI‐1. Markers of bone turnover were not significantly changed by any CEE dosage.

CONCLUSIONS

Six months of treatment with 0.3 mg/day of conjugated equine oestrogen significantly lowers serum levels of total cholesterol and LDL‐cholesterol without causing the adverse increases of triglycerides or factor VIIc, which were observed at higher doses. However, this low‐dose treatment did not yield the maximal LDL‐cholesterol lowering effect. Moreover, the positive effects of HRT on HDL‐cholesterol, apolipoprotein A‐I, lipoprotein (a) and plasminogen activator inhibitor‐1 required at least the medium dose of 0.6 mg conjugated equine oestrogens per day. Therefore, further studies are needed to determine which dose of conjugated equine oestrogens has the optimal effect on cardiovascular risk and bone turnover.
SiCf–SiBC composites: microstructural investigations of the as‐received material and creep tested composites under an oxidative environment
Authors: Farizy G. , Chermant J.‐L. , Sangleboeuf J. C. , Vicens J.
Published: May 2003

SiCf–SiBC composites fabricated by Snecma Propulsion Solide (St Médard en Jalles, France) were investigated by SEM and HRTEM in the as‐received state and after creep tests performed in air, in a temperature range 1423–1573 K, under 170 and 200 MPa. These composites are reinforced by Hi‐Nicalon fibres (Nippon Carbon). A pyrocarbon interphase was first deposited on the fibres. The matrix was then deposited on the fibrous preform by several chemical vapour infiltrations (CVI). As a result the matrix is multilayered and based on the Si–B–C ternary system. This matrix is self‐sealing: this is due to the presence of boron inducing the formation of a sealant glass if the material is heated in an oxidative environment. This glass will protect fibres and fibre/matrix interphases against oxidation. Hi‐Nicalon fibres as well as the different matrix layers were studied by HRTEM and EDX. Some investigations were carried out on the creep‐tested specimens in order to characterize modifications observed in the different constituents of the composites, particularly at the interfaces between the matrix layers and at the fibre/matrix interface. It was shown that several matrix layers crystallized during the creep tests. Moreover, a thin silica layer was observed at the pyrocarbon/matrix interfaces. Differences between the behaviour of the same type of material creep tested under neutral atmosphere are discussed.
Retention of fluorescent probes during aldehyde‐free anhydrous freeze‐substitution
Authors: Hyde G. J. , Davies D. S. , Cole L. , Ashford A. E.
Published: May 2003

Fluorescent probes are widely used for microscopy of live‐cell processes, but few such probes can also be used with classically fixed or otherwise immobilized material, and none has been used without aldehyde fixation, which can introduce artefacts of structure and probe localization. Here we show that the fluorescence patterns in fungal hyphae loaded with chloromethyl aminocoumarin (CMAC), and then anhydrously freeze‐substituted, without any aldehyde fixation, are similar to those seen in living hyphae. Probe loss into the mounting medium (Spurr's resin) with CMAC and five other probes tested indicated that some unwanted solubilization of probe occurred during embedding, but nevertheless vacuoles could be imaged by their retention of probe.
Re‐evaluation of differential phase contrast (DPC) in a scanning laser microscope using a split detector as an alternative to differential interference contrast (DIC) optics
Authors: Amos W. B. , Reichelt S. , Cattermole D. M. , Laufer J.
Published: May 2003

In this paper, differential phase imaging (DPC) with transmitted light is implemented by adding a suitable detection system to a standard commercially available scanning confocal microscope. DPC, a long‐established method in scanning optical microscopy, depends on detecting the intensity difference between opposite halves or quadrants of a split photodiode detector placed in an aperture plane. Here, DPC is compared with scanned differential interference contrast (DIC) using a variety of biological specimens and objective lenses of high numerical aperture. While DPC and DIC images are generally similar, DPC seems to have a greater depth of field. DPC has several advantages over DIC. These include low cost (no polarizing or strain‐free optics are required), absence of a double scanning spot, electronically variable direction of shading and the ability to image specimens in plastic dishes where birefringence prevents the use of DIC. DPC is also here found to need 20 times less laser power at the specimen than DIC.
The locus coeruleus complex of the bottlenose dolphin (Tursiops truncatus) as revealed by tyrosine hydroxylase immunohistochemistry
Authors: Manger Paul R. , Ridgway Sam H. , Siegel Jerome M.
Published: May 2003

Using tyrosine hydroxylase immunohistochemistry we examined the structure of the pontine, or rostral rhombencephalic, catecholaminergic cells groups, which may be collectively termed the locus coeruleus complex (LC), in the bottlenose dolphin. The present study is the first to describe the LC in a cetacean species and, at 1.3 kg, represents the largest non‐human brain to date in which the LC has been investigated. We identified four catecholaminergic cell groups in the dorsal pontine tegementum and peri‐aqueductal gray matter: A6 dorsal (locus coeruleus), A6 ventral (locus coeruleus alpha), A7 (subcoeruleus), and A5 (fifth arcuate nucleus). No patterns of cellular distribution, nuclear subdivision, or cellular morphology indicate specialization of the LC, which might have been anticipated because of the large absolute brain size and unihemispheric sleep phenomenology of cetaceans.
Sensitivity of sleep stages to painful thermal stimuli
Authors: Bentley A. J. , Newton S. , Zio C. D.
Published: May 2003

Many modalities of both acute and chronic pain have been shown to disrupt sleep. Any differences in the intensity of thermal noxious stimulus required to produce arousal from stage 2, slow‐wave sleep (SWS) and rapid eye movement (REM) sleep is unclear. An assessment of reactions of seven male (age 22 ± 2.9 years) and three female subjects (age 21.0 ± 1.0 years) to a range of gradually increasing temperatures was used both when awake and asleep. When awake, subjects assigned five different descriptors to the increasing heat stimulus. During the different stages of sleep, temperatures were increased over the same range as when awake until the subjects aroused from sleep. The possible fluctuations in pain perception due to a time‐of‐night effect were assessed in awake subjects over a 12‐h period from 19:00 to 07:00 hours. During sleep, arousals occurred at significantly higher temperatures during SWS (P < 0.01) and REM sleep (P < 0.05) than during stage 2 sleep. The temperatures causing arousals during SWS and REM sleep were not significantly different and were equivalent to temperatures causing pain tolerance when awake. No changes in pain perception due to time of night were observed. The results show that a higher intensity of thermal noxious stimulus is required to cause arousal from SWS and REM sleep when compared with stage 2 sleep. This would confirm the suspicion that REM sleep and SWS are relatively, and possibly equally, resistant to disruption by noxious stimuli.
A corneal model for slit‐scanning elevation topography
Authors: Cairns G. , Collins A. , McGhee C. N. J.
Published: May 2003

Computerised videokeratography is increasing in sophistication and accuracy. The Orbscan II Videokeratographer combines the advantages of Placido derived and slit‐scanning derived topography, to acquire shape information on the posterior surface of the cornea. The purpose of this paper is to construct a model of slit‐scanning elevation topography and highlight potential sources of variation in this methodology. Ray tracing calculations were performed on a defined, theoretical, spherical model to obtain a pachymetric measurement. These calculations were tested by comparing the pachymetry measurement derived from the model, over a refractive index shift from 1.376 to 1.400 with the pachymetry measurement obtained by Orbscan II, of a human eye, with an identical alteration in refractive index. The two methods of measurement differed by only 0.157 μm, suggesting that the model is a good representation of slit‐scanning elevation topography, and that refractive index variations have only a minimal effect on Orbscan II pachymetry measurement.
The detection of small simulated field defects using multifocal VEPs
Authors: Chan H. L. , Tam W. K. , Chen C. L. , Ng N. C.
Published: May 2003

Introduction: The multifocal visual‐evoked potential (mfVEP) has been widely investigated in the study of diseases of the visual system. However, the sensitivity of the mfVEP in objective detection of field defects has not been determined. This study investigates the variation of the mfVEP responses whilst simulating field defects by using different sizes of mask on the stimulus pattern.

Methods: Simulated field defects of four different sizes (2, 3, 5, and 7 degrees) at two different eccentricities (10 and 16 degrees) were generated on a standard mfVEP dartboard stimulus using opaque masks. These masks were placed at the centre of each dartboard sector and the modified stimuli were used to elicit mfVEPs from 10 normal subjects. The response densities and latencies of N1, P1 of the mfVEP were compared, without and with small simulated field defects.

Results: The minimum size of simulated field defect causing significant response density reduction in P1 and N1 was 5 degrees at both retinal eccentricities. N1 showed similar reduction in response density at both retinal eccentricities, but P1 showed larger reduction at the 10‐degree location than at the 16‐degree location. There was no change in latencies with simulated field defect at either location.

Conclusions: The mfVEP is only sensitive to a simulated field defect equal to or larger than 5 degrees in diameter, and mfVEP has greater sensitivity at 10‐degree eccentricity than at 16‐degree eccentricity.
Correlation analysis of visual field thresholds and scanning laser ophthalmoscopic optic nerve head measurements in glaucoma
Authors: Gulati Vikas , Agarwal Harish C. , Sihota Ramanjit , Saxena Rohit
Published: May 2003

In a cross‐sectional study of 50 consecutive primary open‐angle glaucoma cases, full threshold 30‐2 visual fields on Humphrey Visual Field Analyser were correlated to stereometric parameters obtained using a scanning laser ophthalmoscope (HRT II). The strength of linear correlation between the stereometric parameters and visual thresholds was used to generate a correspondence map between the optic disc and the visual field. Rim/disc area ratio and cup/disc area ratio correlated with the visual thresholds at the highest number of points in the visual fields. Thresholds at superior hemifield locations correlated best with the rim/disc area ratio and cup/disc area ratio in the inferonasal sector and the ones in the inferior hemifield correlated best with the rim/disc area ratio and cup/disc area ratio in the superotemporal sector. Optic disc parameters correlated better with inferior field locations and non‐edge points than superior field locations and edge points. The data indicate that rim/disc area ratio and cup/disc area ratio measurements on HRT II have a good correlation with visual field damage seen on automated visual fields.
Oculocardiac reflex caused by contact lenses
Authors: Mimura Tatsuya , Amano Shiro , Funatsu Hideharu , Araie Makoto , Kagaya Fumie , Kaji Yuichi , Oshika Tetsuro , Yamagami Satoru , Okada Eichi
Published: May 2003

Purpose: To report two cases of patients who fell unconscious because of the oculocardiac reflex when attempting to wear contact lenses.

Case reports: Case 1: A 15‐year‐old healthy boy came to our clinic to be fitted with contact lenses. As soon as a hard contact lens was inserted forcibly, he became unconscious. Case 2: A 22‐year‐old man fell unconscious the instant that the eye was compressed with a hard contact lens. Neither patient had used glasses or contact lenses before. Their blood pressure was decreased while unconscious. They recovered consciousness after about 10 min, and nausea and vomiting settled subsequently. Contact lens insertion was tried again carefully after 1 week avoiding compression of the eyes and there were no problems. They are currently using contact lenses without any problems.

Conclusion: Insertion of contact lenses may rarely provoke the oculocardiac reflex.
Intact satellite cells lead to remarkable protection against Smn gene defect in differentiated skeletal muscle
Authors: Nicole Sophie , Desforges Benedicte , Millet Gaelle , Lesbordes Jeanne , Cifuentes-Diaz Carmen , Vertes Dora , Cao My Linh , De Backer Fabienne , Languille Laetitia , Roblot Natacha , Joshi Vandana , Gillis Jean-Marie , Melki Judith
Published: May 2003

Deletion of murine Smn exon 7, the most frequent mutation found in spinal muscular atrophy, has been directed to either both satellite cells, the muscle progenitor cells and fused myotubes, or fused myotubes only. When satellite cells were mutated, mutant mice develop severe myopathic process, progressive motor paralysis, and early death at 1 mo of age (severe mutant). Impaired muscle regeneration of severe mutants correlated with defect of myogenic precursor cells both in vitro and in vivo. In contrast, when satellite cells remained intact, mutant mice develop similar myopathic process but exhibit mild phenotype with median survival of 8 mo and motor performance similar to that of controls (mild mutant). High proportion of regenerating myofibers expressing SMN was observed in mild mutants compensating for progressive loss of mature myofibers within the first 6 mo of age. Then, in spite of normal contractile properties of myofibers, mild mutants develop reduction of muscle force and mass. Progressive decline of muscle regeneration process was no more able to counterbalance muscle degeneration leading to dramatic loss of myofibers. These data indicate that intact satellite cells remarkably improve the survival and motor performance of mutant mice suffering from chronic myopathy, and suggest a limited potential of satellite cells to regenerate skeletal muscle.
Ever Closer Cooperation? The Limits of the ‘Norwegian Method’ of European Integration
Authors: Eliassen Kjell A. , Sitter Nick
Published: May 2003

The ‘No’ majorities in two referendums on European Community/Union (EC/EU) membership have set clear formal limits to Norway's participation in European integration. However, pro‐EU parliamentary majorities have tended to produce governments that seek as close cooperation with the EU as possible. This involves a kind of quasi‐membership of the EU, particularly in the light of cooperation beyond the limits of the European Economic Area (EEA). The result has been a ‘Norwegian method’ of European integration that combines access to the Single Market with efforts to ‘purchase’ participation in other policy areas and adapt to changing EU policies, legislation and treaties. Given the supranational character of the EU's Single Market rules, this kind of quasi‐membership goes considerably further than non‐members’ participation in most other international organisations. Although the EEA system has worked to the parties’ satisfaction, Norway's efforts to keep up with a changing Single Market, maintain the institutions in the face of treaty change and enlargement, and accommodate new developments pertaining to the EU's second and third pillars represent considerable challenges to the Norwegian method of integration.
The Structure of Budget Demands in Denmark, Norway And Sweden
Authors: Borre Ole
Published: May 2003

Data on people's attitudes to items on the public budgets are found in the International Social Science Programme (ISSP) Role of Government surveys and Danish national election surveys 1990–1998. These data are factor analysed to validate a three‐way agenda that postulates three main goals or functions of the state: the authoritarian state, the welfare state, and the humanitarian state. The factor solution is very similar in Denmark, Norway, Sweden, and the four largest European Union (EU) countries, and on many points consistent with theories of value change and new politics.

Based on the factor analysis, the support for each of the three agendas is analysed for voters of different parties in the three Scandinavian party systems. We find that all three systems are structured in at least two dimensions, the welfare dimension and the humanitarian vs. authoritarian dimension. These data therefore point to the existence of a ‘new politics’ dimension that is similar in the three party systems insofar as it contains the same five budget items. However, the opinion climate differs somewhat between the three countries. The support for the humanitarian agenda is lowest in Norway, whereas the support for the authoritarian agenda is highest in Denmark.
Formation of Disulfide-Linked Complexes between the Three Minor Envelope Glycoproteins (GP
2b
, GP
3
, and GP
4
) of Equine Arteritis Virus
Authors: Wieringa Roeland , de Vries Antoine A. F. , Rottier Peter J. M.
Published: May 2003

Equine arteritis virus (EAV) is an enveloped, positive-stranded RNA virus belonging to the family
Arteriviridae
of the order
Nidovirales
. Six transmembrane proteins have been identified in EAV particles: the nonglycosylated membrane protein M and the glycoprotein GP
5
(previously named G
L
), which occur as disulfide-bonded heterodimers and are the major viral envelope proteins; the unglycosylated small envelope protein E; and the minor glycoproteins GP
2b
(formerly designated G
S
), GP
3
, and GP
4
. Analysis of the appearance of the GP
2b
, GP
3
, and GP
4
proteins in viral particles by gel electrophoresis under reducing and nonreducing conditions revealed the occurrence of two different covalently linked oligomeric complexes between these proteins, i.e., heterodimers of GP
2b
and GP
4
and heterotrimers of GP
2b
, GP
3
, and GP
4
. Shortly after their release from infected cells, virions contained mainly cystine-linked GP
2b
/GP
4
heterodimers, which were subsequently converted into disulfide-bonded GP
2b
/GP
3
/GP
4
trimers through the covalent recruitment of GP
3
. This process occurred faster at a higher pH but was arrested at 4°C. Furthermore, the conversion was almost instantaneous in the presence of the thiol oxidant diamide. In contrast, the sulfhydryl-modifying agent
N
-ethylmaleimide inhibited the formation of disulfide-bonded GP
2b
/GP
3
/GP
4
trimers. Using sucrose density gradients, we could not demonstrate a noncovalent association of GP
3
with the cystine-linked GP
2b
/GP
4
dimer in freshly released virions, nor did we observe higher-order structures of the GP
2b
/GP
4
or GP
2b
/GP
3
/GP
4
complexes. Nevertheless, the instantaneous diamide-induced formation of disulfide-bonded GP
2b
/GP
3
/GP
4
heterotrimers at 4°C suggests that the three minor glycoproteins of EAV are assembled as trimeric complexes. The existence of a noncovalent interaction between the cystine-linked GP
2b
/GP
4
dimer and GP
3
was also inferred from coexpression experiments showing that the presence of GP
3
increased the electrophoretic mobility of the disulfide-bonded GP
2b
/GP
4
dimers. Our study reveals that the minor envelope proteins of arteriviruses enter into both covalent and noncovalent interactions, the function of which has yet to be established.
Herpes Simplex Virus Type 1 Portal Protein UL6 Interacts with the Putative Terminase Subunits UL15 and UL28
Authors: White Colleen A. , Stow Nigel D. , Patel Arvind H. , Hughes Michelle , Preston Valerie G.
Published: May 2003

The herpes simplex virus type 1 (HSV-1) UL6, UL15, and UL28 proteins are essential for cleavage of replicated concatemeric viral DNA into unit length genomes and their packaging into a preformed icosahedral capsid known as the procapsid. The capsid-associated UL6 DNA-packaging protein is located at a single vertex and is thought to form the portal through which the genome enters the procapsid. The UL15 protein interacts with the UL28 protein, and both are strong candidates for subunits of the viral terminase, a key component of the molecular motor that drives the DNA into the capsid. To investigate the association of the UL6 protein with the UL15 and UL28 proteins, the three proteins were produced in large amounts in insect cells with the baculovirus expression system. Interactions between UL6 and UL28 and between UL6 and UL15 were identified by an immunoprecipitation assay. These results were confirmed by transiently expressing wild-type and mutant proteins in mammalian cells and monitoring their distribution by immunofluorescence. In cells expressing the single proteins, UL6 and UL15 were concentrated in the nuclei whereas UL28 was found in the cytoplasm. When the UL6 and UL28 proteins were coexpressed, UL28 was redistributed to the nuclei, where it colocalized with UL6. In cells producing either of two cytoplasmic UL6 mutant proteins and a functional epitope-tagged form of UL15, the UL15 protein was concentrated with the mutant UL6 protein in the cytoplasm. These observed interactions of UL6 with UL15 and UL28 are likely to be of major importance in establishing a functional DNA-packaging complex at the portal vertex of the HSV-1 capsid.
Acute glomerulonephritis
Authors: Vinen C S , Oliveira D B G
Published: May 2003

Glomerulonephritis is an important cause of renal failure thought to be caused by autoimmune damage to the kidney. While each type of glomerulonephritis begins with a unique initiating stimulus, subsequent common inflammatory and fibrotic events lead to a final pathway of progressive renal damage. In this article the different forms of inflammatory glomerulonephritis and their diagnosis are discussed. In a review of therapy both immediate life saving treatment given when glomerulonephritis causes acute renal failure and more specific treatments designed to modify the underlying mechanisms of renal injury are considered.
Iron deficiency anaemia: are the British Society of Gastroenterology guidelines being adhered to?
Authors: Patterson R N , Johnston S D
Published: May 2003

Background

The British Society of Gastroenterology (BSG) issued guidelines on the investigation of iron deficiency anaemia (IDA) ensuring standardised and comprehensive gastrointestinal investigation in all patients. It was apparent that not all patients in the authors’ hospital were investigated according to these guidelines.

Objective

To determine whether patients who were referred for upper gastrointestinal endoscopy for investigation of IDA were confirmed to be iron deficient, and whether the BSG guidelines were being fully implemented.

Methods

All patients referred for upper gastrointestinal endoscopy over an 18 month period on a computer database (Endoscribe) were reviewed. Haematology, biochemistry, and radiology results were obtained and the frequency of the various diagnoses recorded.

Results

A total of 320 patients (133 male; mean age 71.5 years) were initially referred for upper gastrointestinal endoscopy for investigation of IDA, of whom 95 were iron deficient. Of these, 44 (46%) had duodenal biopsies performed, three (7%) of whom were diagnosed with coeliac disease. Five patients were diagnosed with upper gastrointestinal carcinoma (one oesophageal, four gastric). Of the remaining 87 patients, 65 (75%) underwent lower gastrointestinal investigations with four having colorectal carcinoma, four colonic polyps, and one angiodysplasia.

Conclusions

Duodenal biopsies were performed in less than half of the patients. In those not diagnosed with coeliac disease or upper gastrointestinal carcinoma, only three quarters underwent lower gastrointestinal assessment. Approximately 10% were diagnosed with gastrointestinal malignancy as a cause for their anaemia and in 66% of patients no gastrointestinal cause was found. All physicians need to be made fully aware of the BSG guidelines for investigation of IDA.
Iatrogenic injury to the breast bud causing breast hypoplasia
Authors: Goyal A , Mansel R E
Published: May 2003

A 14 year old girl with iatrogenic breast asymmetry is reported. She had multiple operations to the left anterior chest wall in the neonatal period for diaphragmatic hernia that resulted in multiple scars, which damaged the left breast bud. A better thoracotomy incision avoiding the breast bud could prevent later breast hypoplasia.
Unusual cause of infective discitis in an adolescent
Authors: Sayana M K , Chacko A J , Mc Givney R C
Published: May 2003

The first case of infective discitis caused by Eikenella corrodens in an adolescent is presented. The need for anaerobic cultures when dealing with infective pathology in the spine is stressed. A 14 year old boy presented with acute exacerbation of back pain, which showed characteristics of infective discitis after magnetic resonance imaging. Computed tomography guided biopsy grew E corrodens in anaerobic cultures that was sensitive to ampicillin, co- amoxiclav, cefadroxil, and cefotaxime. This patient responded well to co-amoxiclav and recovered without any surgical intervention.
A SUPERSYMMETRIC MODEL WITH THE GAUGE SYMMETRY SU(3)1 × SU(2)1 × U(1)1 × SU(3)2 × SU(2)2 × U(1)2
Authors: KÖRNER J. G. , LIU CHUN
Published: May 2003

A supersymmetric model with two copies of the Standard Model gauge groups is constructed in the gauge mediated supersymmetry breaking scenario. The supersymmetry breaking messengers are in a simple form. The Standard Model is obtained after first step gauge symmetry breaking. In the case of one copy of the gauge interactions being strong, a scenario of electroweak symmetry breaking is discussed, and the gauginos are generally predicted to be heavier than the sfermions.
PARTICLE PRODUCTION RELATED TO THE TUNNELING IN FALSE VACUUM DECAY
Authors: MAZIASHVILI MICHAEL
Published: May 2003

Motivated by the work of Mersini, the particle production related to the tunneling in false vacuum decay is carefully investigated in the thin-wall approximation. It is shown that in this case the particle production is exponentially suppressed even when the momentum is comparable to the curvature scale of the bubble. The number of created particles is ultraviolet finite.
Biosynthesis and Metabolism of Brassinosteroids
Authors: Fujioka Shozo , Yokota Takao
Published: May 2003

Brassinosteroids (BRs) are steroid hormones that regulate the growth and development of plants. Detailed study of the biosynthesis of brassinolide, a C28BR, revealed that two parallel routes, the early and late C-6 oxidation pathways, are connected at multiple steps and also are linked to the early C-22 oxidation pathway. Thus, BR biosynthetic pathways are highly networked. Furthermore, the biosynthesis of C27BRs was shown to proceed in a similar way to that of C28BRs. Information on enzymes and genes involved in the BR biosynthesis, as well as their regulation, has been obtained using BR-deficient and BR-insensitive mutants. In addition, the biosynthesis of sterols, which were recently recognized not only as precursors of BRs and membrane constituents, but also as modulators of plant development, is discussed. Various metabolic reactions of BRs including epimerization, oxidation, and conjugation are also summarized.
The Impact of Peripartum Factors on the Onset and Duration of Lactation
Authors: Sievers E. , Haase S. , Oldigs H.-D. , Schaub J.
Published: May 2003

Knowledge of peripartum indicators of those mother-infant pairs that are at increased risk of early failure of lactation may improve specific support of breastfeeding. Mode of delivery, labor complications, hyperbilirubinemia, milk intake and weight development were evaluated in healthy term infants in a hospital (n = 338). Delayed onset of lactation was observed in primiparae and in study participants with peripartum complications. The quantitative intake of human milk, assessed by test weighing 0–24 h and 24–48 h after the onset of lactation, was not significantly different between these groups. In addition, volume intake, weight gain and lactation success were tracked in 77 infants. Partial feeding of infant formula or an intake of <150 g of human milk per day 24–48 h after the onset of lactation was linked to weaning within 4 weeks. Ninety-one percent of the infants were exclusively breastfed at discharge; this value had declined to 49, 35 and 20% at 4, 12 and 20 weeks, respectively. Peripartum factors may contribute to early lactation failure; the long-term success of breastfeeding was predominantly determined outside the hospital.
Modulation of Mucin Synthesis by γ-Interferon in Human Colon Adenocarcinoma Cells
Authors: Niv Yaron , Koren Rivka
Published: May 2003

Objectives: Recombinant human interferon has been shown to enhance the expression of histocompatibility antigens and certain tumor-associated antigens in a variety of carcinoma cell lines. Since many tumor-associated antigens are mucins, we investigated the effect of recombinant human γ-interferon on mucin production and secretion by colon cancer cell lines. Methods: Control and γ-interferon-treated cells were labeled with [3H]glucosamine in DMEM-H16 medium with 5% FCS for 24 h. Analysis was performed by gel filtration on Sepharose CL-4B columns, and the high-molecular-weight glycoprotein eluted at the void volume from the cytosol and medium was counted (expressed as dpm/4 × 106 cells). In another experiment the void volume was compared to concentration curves of standard mucins (expressed as mg/107 cells). Results: γ-Interferon increased mucin synthesis in HT-29 and LIM-6 cells, but not in LS174T and CACO2 cells. In HT-29 and LIM-6 cells, mucin synthesis was induced by γ-interferon in a dose-dependent manner. The percentage of mucin secreted into the medium was also increased. Conclusion: The heterogeneity of response of human colon cancer cell lines to γ-interferon by mucin production may limit the specific role of γ-interferon as a modulator of mucin-type tumor-associated antigens.
Food Contents and Biological Activity of 25-Hydroxyvitamin D: A Vitamin D Metabolite to Be Reckoned With?
Authors: Ovesen Lars , Brot Christine , Jakobsen Jette
Published: May 2003

Only a limited number of foods naturally contain vitamin D such as fish, meat and offal, and eggs, and milk and dairy products. However, all these foods in addition contain the metabolite 25-hydroxyvitamin D (25OHD). From the few systematic studies which have been performed the food contents of 25OHD in animal foods are usually low but vary. Contents are typically very low in milk and fish (<0.1 µg/100 g), somewhat higher in meat and offal (0.2–0.4 µg/100 g) and up to 1 µg/100 g in egg yolk. It has been demonstrated that 25OHD is absorbed better and faster from the diet than native vitamin D and has metabolic effects of its own in regulating cell growth and calcium metabolism. Thus, the biological activity of 25OHD is greater than that of native vitamin D. However, there is as yet no consensus on the conversion factor that should be used for 25OHD to calculate vitamin D activity. Depending on the testing system used the factor varies from 1.5 to 5. If food contents and the higher potency of 25OHD are not included in dietary intake surveys, true vitamin D intake will be underestimated.