bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fetal gastric size in normal and abnormal pregnancies
Authors: Sase M. , Asada H. , Okuda M. , Kato H. 
Published: March 2003

AbstractObjectiveThe aim of this observational study was to construct an ultrasound index of fetal gastric size for the prenatal detection of congenital digestive tract obstruction.SubjectsA total of 386 fetal measurements were performed in routine ultrasonographic examinations of women with normal singleton pregnancies between 18 and 39 weeks of gestation. Gastric measurements were also performed in 13 fetuses with digestive tract obstruction.MethodsThe ultrasound plane which included the pylorus and which provided the largest stomach area was used for definition and measurement of gastric area and maximal longitudinal dimension. The transverse section at the center of the gastric corpus was used for transverse and anteroposterior dimensions. Gastric volumes were calculated as a prolate ellipsoid. The gastric area ratio was defined as the gastric area divided by the transverse abdominal area. Biparietal diameter (BPD) and abdominal transverse area were also measured.ResultsThe fetal gastric area was significantly correlated with fetal gastric volume (r = 0.91) and gestational age (r = 0.74). However, the correlation coefficient for gastric area with gestational age was smaller than those of the BPD (r = 0.97) with gestational age and abdominal transverse area with gestational age (r = 0.97). Gastric area ratio decreased slightly towards term. The gastric area ratio was below the 95% confidence intervals for the predicted values in all five fetuses with esophageal atresia, and exceeded the 95% confidence intervals in seven of the eight fetuses with duodenal atresia or intestinal tract obstruction.ConclusionFetal gastric area correlates with ultrasound‐determined gastric volume measurements and appears to be useful in the assessment of digestive tract anomalies. Copyright © 2002 ISUOG
Dynamic three‐dimensional color Doppler ultrasound of human fetal intracardiac flow
Authors: Deng J. , Yates R. , Sullivan I. D. , Mcdonald D. , Linney A. D. , Lees W. R. , Anderson R. H. , Rodeck C. H. 
Published: March 2003

AbstractObjectivesTo develop dynamic three‐dimensional ultrasound techniques for prenatal imaging of the intracardiovascular flow as well as the cardiovascular structure to address difficulties in assessing the spatially complex hemodynamics and morphology of the fetal heart.MethodsGray‐scale and color (velocity) Doppler echocardiography were performed on 12 fetuses to provide serial anatomical and rheological tomograms which were spatially registered in three dimensions. Using a second ultrasound machine simultaneously, spectral Doppler ultrasound was performed to record umbilical arterial waveforms, thus providing the temporal (fourth) dimension in terms of the cardiac cycle and facilitating removal of motion artifacts.ResultsAcquisitions were successful in eight of 15 attempts. Imaging of the flow of blood in four dimensions was achieved in six of the eight datasets. In one case with complex cardiac malformations, three‐dimensional reconstructions at systole and diastole offered dynamic diagnostic views not appreciated on the cross‐sectional images.ConclusionsOur novel technique has made possible the prenatal visualization of the spatial distribution and true direction of intracardiac flow of blood in four dimensions in the absence of motion artifacts. The technique suggests that diagnosis of cardiac malformations can be made on the basis of morphological and hemodynamic changes throughout the entire cardiac cycle, offering unique and significant information complementary to conventional techniques. Further work to integrate the several non‐purpose‐built machines into a single system will improve the rate of acquisition of data, and may provide a new means of imaging and modeling structure and hemodynamics, not only for the fetal heart but for many other moving body parts.
Increased first‐trimester nuchal translucency as a prenatal manifestation of salt‐wasting congenital adrenal hyperplasia
Authors: Fincham J. , Pandya P. P. , Yuksel B. , Loong Y. M , Shah J. 
Published: March 2003

AbstractCongenital adrenal hyperplasia (CAH) is an autosomal recessive disorder that results from a deficiency in one or other of the five enzymes of cortisol biosynthesis. The most common form of CAH is 21‐hydroxylase deficiency (21‐OHD) and this may be manifest clinically in the neonatal period as a life threatening salt‐wasting condition alongside genital ambiguity. Prenatal diagnosis is available for CAH, however, there is poor correlation between the specific genotype and the phenotypic expression of the condition. We report two cases of severe salt‐wasting CAH in one family that presented in both pregnancies with increased nuchal translucency (NT) in the first trimester. This is the first report of the association, between increased NT and CAH 21‐OHD.
Professor Edward George Gray, FRS (1924–1999)
Authors: GUILLERY R. W. 
Published: March 2003

Professor George Gray, who died in August 1999, had a notable career as a pioneer electron microscopist of neural tissues. His name is still attached to synapses, which can be classified as Gray type 1 (symmetric) or type 2 (asymmetric), and in addition he made a number of other profound contributions to our knowledge of synaptic structures.He started his academic career late, having worked before the second World War as a bank clerk, and then serving in the Navy, patrolling for U‐boats in the North Sea and Atlantic for 4 years during the latter part of the war. He had an early interest in zoology, particularly in marine biology and microscopy and when he left the Navy he took the opportunity to work for a degree in Zoology at the University of Wales in Aberystwyth. A first class honours degree was followed by a PhD on melanophores in teleosts. It was fortunate that the external examiner for the thesis was J. Z. Young, who was impressed by the work and by George, and who invited George to work as his assistant in the preparation of The Life of the Mammals in the Anatomy Department at University College London.
Origin of the vertebrate inner ear: evolution and induction of the otic placode
Authors: STREIT ANDREA 
Published: March 2003

abstractThe vertebrate inner ear forms a highly complex sensory structure responsible for the detection of sound and balance. Some new aspects on the evolutionary and developmental origin of the inner ear are summarised here. Recent molecular data have challenged the longstanding view that special sense organs such as the inner ear have evolved with the appearance of vertebrates. In addition, it has remained unclear whether the ear originally arose through a modification of the amphibian mechanosensory lateral line system or whether both evolved independently. A comparison of the developmental mechanisms giving rise to both sensory systems in different species should help to clarify some of these controversies. During embryonic development, the inner ear arises from a simple epithelium adjacent to the hindbrain, the otic placode, that is specified through inductive interactions with surrounding tissues. This review summarises the embryological evidence showing that the induction of the otic placode is a multistep process which requires sequential interaction of different tissues with the future otic ectoderm and the recent progress that has been made to identify some of the molecular players involved. Finally, the hypothesis is discussed that induction of all sensory placodes initially shares a common molecular pathway, which may have been responsible to generate an ‘ancestral placode’ during evolution.
Evaluation of three‐dimensional glenoid structure using MRI
Authors: INUI HIROAKI , SUGAMOTO KAZUOMI , MIYAMOTO TAKASHI , MACHIDA AKITOSHI , HASHIMOTO JUN , NOBUHARA KATSUYA 
Published: March 2003

The tilting angle and the shape of the glenoid cavity are considered to relate closely to shoulder stability. They are also important when planning arthroplasty and developing new designs. This study examines the glenoid cavity using 3‐dimensional MRI. Forty volunteers (20 men, 20 women; average age 21.4; range 18–35 y) were enrolled in the study. The tilting angles of the glenoid bone were measured in 5 consecutive axial planes perpendicular to the glenoidal long axis. Cross sections were divided into 3 types (concave, flat, convex) according to the shape on each plane.The average tilting angles for the 5 planes from the bottom to the top were 3.3±4.1, 1.4±3.8, −0.6±1.9, −1.4±3.3, and −6.2±3.3 degrees anteriorly, indicating that the 3‐dimensional bony structure of the glenoid was twisted anteriorly to posteriorly. Images on the bottom plane consisted of 82.5% concave type, 15% flat type and 2.5% convex type, while only 3 cases (7.5%) showed concave at the top plane. The shape of the glenoid cavity is thought to be conducive to glenohumeral motion and stability.
Modulation of angiogenesis is effective in a model of rheumatoid arthritis
Authors: Afuwape A. O. , Paleolog E. M. 
Published: March 2003

A feature of rheumatoid arthritis (RA) is prominent hyperplasia of the synovium, which results in an increased distance between the invasive pannus and the existing synovial vasculature. Concomitantly the hyperplastic tissue imposes an augmented metabolic demand on the pre‐existing vasculature. As a consequence the synovium in RA becomes hypoxic, resulting in an increased rate of formation of new blood vessels, to supply nutrients and oxygen. Targeting the vasculature in RA is a potential therapeutic approach in RA. VEGF, a key vascular permeability and angiogenic factor, is expressed in RA. In this study we utilised adenovirus expressing the secreted form of the extracellular domain of the Flt‐1 VEGF receptor (sFlt‐1) to inhibit VEGF in the collagen‐induced arthritis (CIA) model, to determine whether blocking the effects of vegf might be an effective treatment for RA.AdvsFlt‐1, administered intravenously on the first day of arthritis, significantly suppressed CIA. For example, on d 6 of arthritis the mean increase in paw thickness, which reflects oedema, for untreated and null adenovirus‐treated animals was 0.23 ± 0.05 mm and 0.38 ± 0.08, respectively, compared to 0.07 ± 0.05 for AdvsFlt‐1‐treated mice (P < 0.001 vs. Adv0‐treated and untreated mice by 2‐way anova). Western blot analyses revealed the presence of a 100‐kDa band, corresponding to human sFlt‐1, in liver extracts from arthritic mice infected with AdvsFlt‐1 at 24 h but not 72 h after infection. This band was absent in liver extracts from Adv0‐infected mice and all synovial extracts. Measurement of protein levels by ELISA demonstrated the presence of sFlt‐1 in liver, synovium and serum, although levels declined by 72 h post infection. These data suggest efficient but transient expression of sFlt‐1. Sera from adenovirus infected mice were found to contain antiviral antibodies and additionally, sera from AdvsFlt‐1‐infected but not Adv0‐infected mice recognised human recombinant sFlt‐1.These observations demonstrate that adenoviral mediated delivery of human sFlt‐1 leads to transient gene expression and suppression of CIA. This effect is reduced later in the course of disease due to the expression of antiadenovirus as well as antisFlt‐1 antibodies. Future studies will assess the effect of combination treatment, using AdvsFlt‐1 together with anti‐TNF(antibody, to prolong the beneficial effects of VEGF blockade. These results suggest that blocking the pro‐angiogenic and permeability action of VEGF may be beneficial for treatment of RA.
The aquaporin‐1 water channel protein is abnormally expressed in oedematous human brain tumours
Authors: Papadopoulos M. C. , Saadoun S. , Krishna S. , Bell B. A. , Davies D. C. 
Published: March 2003

The aquaporins (AQPs) comprise a family of at least 10 highly conserved water channel proteins. Of these only AQP1 and AQP4 are significantly expressed in the brain. In normal brain AQP1 is expressed by the choroid plexus, whereas AQP4 is expressed by astrocyte end‐feet surrounding brain microvessels and forming the glial limiting membrane under the pia mater and ependyma. In order to begin to investigate whether AQP1 is involved in brain water homeostasis, the expression of AQP1 was compared in normal human brain and in human brain tumours where brain water homeostasis is disrupted. Formalin fixed, paraffin embedded samples of morphologically normal human brain (n = 5), low‐grade (Daumas‐Duport I or II) astrocytomas (n = 5), high‐grade (Daumas‐Duport III or IV) astrocytomas (n = 5) and adenocarcinoma metastases to the brain (n = 5) were obtained from patients who underwent surgery at Atkinson Morley’s Hospital during 1998–9. Astrocytomas and metastatic adenocarcinomas were investigated because they are the commonest human brain tumours. Immunocytochemistry was performed using a polyclonal rabbit anti‐AQP1 primary antibody (AB3065, Chemicon). The immunoreactivity was visualised using immunoperoxidase and diaminobenzidine. In all samples of non‐neoplastic and neoplastic brain, AQP1 immunoreactivity was found over erythrocyte cell membranes. In morphologically normal human brain AQP1 immunolabelling was occasionally observed over microvessel endothelial cells. In 4/5 low grade astrocytomas AQP1 immunolabelling was present over most microvessel endothelial cells and at the periphery of most tumour cells. In all high grade astrocytomas, dense AQP1 immunolabelling was present over most microvessel endothelial cells and both at the periphery and throughout the cytoplasm of most tumour cells. In all metastatic adenocarcinomas AQP1 immunolabelling was present over most microvessel endothelial cells. In 2/5 adenocarcinoma samples AQP1 immunoreactivity was also present in cells with the morphology of reactive astrocytes that were in close proximity to the tumour cells. The presence of AQP1 immunoreactivity in cells within human brain tumours that do not normally express AQP1 and the increasing AQP1 expression with tumour severity, suggest that AQP1 may play a role in the formation of brain tumour oedema. Since brain oedema increases the morbidity and mortality of patients with brain tumours, blocking the AQP1 water channel may provide a way to improve the prognosis of such patients.
Three‐dimensional sonographic evaluation of the fetal lumbar spinal canal
Authors: Wallny Thomas , Schild Ralf L. , Fimmers Rolf , Hansmann Manfred E. 
Published: March 2003

AbstractIn a prospective cross‐sectional ultrasound study the size of the fetal lumbar spinal canal was evaluated to determine reference values for the lumbar part of the vertebral canal. One hundred and sixty‐seven pregnant women undergoing routine obstetric ultrasound were studied between 16 and 41 weeks of gestation. Exclusion criteria consisted of structural fetal anomalies or growth restriction. Area and volume of the vertebral canal at L1, L3 and L5 were calculated by three‐dimensional (3D) ultrasound. Length of the lumbar spine was also determined. The size of the spinal canal and spinal length correlated well with gestational age. No gestational‐age‐dependent differences in area and volume measurements between upper and lower lumbar spine were found. The results provide an in vivo assessment of the spinal canal by 3D ultrasound over the entire gestation period.
Immunocytochemical localization of angiotensin II receptor subtypes 1 and 2 in the porcine fetal, prepubertal and postpubertal ovary
Authors: Shuttleworth Gail , Hunter Morag G. , Robinson Graham , Broughton Pipkin Fiona 
Published: March 2003

AbstractThere is considerable evidence for a mammalian ovarian renin–angiotensin system, which may influence ovulation, angiogenesis and steroidogenesis via the autocrine and/or paracrine actions of the biologically active product of the cascade, angiotensin II (AngII). There are two characterized AngII receptors – type 1, AT1 and type 2, AT2. We report the localization of these receptor subtypes within porcine fetal, prepubertal and postpubertal ovaries. Positive staining for AT1 and AT2 receptors was observed in egg nests in all fetal ovaries studied, as well as in a defined two‐cell layer at the ovarian periphery. In prepubertal tissue, positive AT1 and AT2 staining was localized to granulosa cells adjacent to the basement membrane of pre‐antral and antral follicles, with no staining in the thecal layer. There was immunostaining for both receptors in prepubertal oocytes and zona pellucida. In postpubertal tissue, positive AT1 and AT2 immunostaining was localized to areas of putative neovascularization, the zona pellucida and the oocyte. Further AT1 staining was located to the postpubertal antral follicle granulosa cells. The results indicate that there are higher densities of AT1 receptors than AT2 receptors in the porcine fetal, prepubertal and postpubertal ovary, and this has profound implications for the role of AngII in ovarian development.
Developmental mechanisms underlying polydactyly in the mouse mutant Doublefoot
Authors: Crick Alexandra P. , Babbs Christian , Brown Jennifer M. , Morriss‐Kay Gillian M. 
Published: March 2003

AbstractThe pre‐axial polydactylous mouse mutant Doublefoot has 6–9 digits per limb but lacks anteroposterior polarity (there is no biphalangeal digit 1). It differs from other polydactylous mutants in showing normal Shh expression, but polarizing activity (shown by mouse‐chick grafting experiments) and hedgehog signalling activity (shown by expression of Ptc1) are present throughout the distal mesenchyme. The Dbf mutation has not yet been identified. Here we review current understanding of this mutant, and briefly report new results indicating (1) that limb bud expansion is concomitant with ectopic Ihh expression and with extension of the posterior high cell proliferation rate into the anterior region, and (2) that the Dbf mutation is epistatic to Shh in the limb.
The effect of the slow‐to‐green mutation on cell division during leaf initiation and early leaf growth in Lolium temulentum
Authors: MOSES LYNNE , OUGHAM HELEN J. , FRANCIS DENNIS 
Published: March 2003

SUMMARYCell division was examined during leaf initiation in the slow‐to‐green mutant of Lolium temulentum L. to test the hypothesis that the cell cycle in the leaf primordium is a key regulator of the well characterized reduction in final leaf length in the mutant compared with that of the wild type. The cell doubling time (cdt, by colchicine method) was substantially longer in the youngest leaf primordium (YLP) of the mutant (107 h) than in the wild type (43 h) although the duration of the most rapid cell cycle (cc, by percentage labelled mitoses method) was between 18–20 h in each. As a consequence, the proportion of rapidly proliferating cells was only 20 % in the mutant compared with 47 % in the wild type. The size of the shoot apical meristem and the plastochron were similar between genotypes which indicates that the shoot meristem was largely buffered from the effects of the mutation. Mitotic cell area was also similar in the YLP of both genotypes. However, as the leaf elongated, mitotic cell area and interphase cell size were significantly larger in the mutant compared with the wild type. This change was coupled with a reduced number of cells per unit length of leaf in the mutant. The data are consistent in showing that the proportion of rapidly proliferating cells in the YLP (but not the rate of cell division) is a key parameter which influences growth of the leaf.
Effects of elevated CO2, nitrogen and phosphorus on the growth and photosynthesis of two upland perennials: Calluna vulgaris and Pteridium aquilinum
Authors: WHITEHEAD S. J. , CAPORN S. J. M. , PRESS M. C. 
Published: March 2003

SUMMARYBracken (Pteridium aquilinum (L.) Kuhn) and heather (Calluna vulgaris (L.) Hull) are important upland species which often grow in close proximity in the UK. The effects of factorial treatments of elevated atmospheric CO2 (539 μmol mol−1 as opposed to ambient atmospheric CO2 concentrations of 355 μmol mol−1), added N (50 kg N ha−1 as NH4NO3) and added P (20 kg P ha−1 as NaH2PO4) on the performance of these two species were studied under controlled environmental conditions using container‐grown plants. Plants grown and measured at high CO2 had higher rates of net photosynthesis than those grown and measured in ambient CO2. This increase was greater in heather than in bracken and resulted in a large stimulation of growth in the former. In bracken there was no significant change in plant size or phenology. The increase in biomass of heather in high CO2 was greatest in the absence of added nutrients and lowest when both N and P were supplied. The growth and photosynthesis of both plants responded positively to the supply of P alone or P with N (in both CO2 atmospheres), but there was little response to N alone. The implications of these findings for bracken and heather growing in the field under conditions of an elevated CO2 atmosphere and greater nutrient availability are discussed.
Costs and benefits of mycorrhizal infection in a spring ephemeral, Erythronium americanum
Authors: LAPOINTE LINE , MOLARD JULIE 
Published: March 2003

summarySpring ephemerals have evolved specific growth strategies that take advantage of the high photon fluence rates of early spring. These strategies involve a sequential growth of different organs. Erythronium americanum (Ker‐Gawl), a common spring ephemeral of northern maple forests, produces its roots in the autumn, although stems and leaves develop in the spring. Mycorrhizal infection of the root system occurs very rapidly and intensively. The fungi thus depend on carbohydrate reserves accumulated in the corm (underground reserve organ) for their growth and development through the winter. We found that the presence of mycorrhizas drastically decreases root growth during the cold period and is more costly of carbohydrate reserves than root growth alone. However, during the spring, the presence of mycorrhizas fully benefits the plant: we measured an annual growth rate of mycorrhizal plants twice that of fungicide‐treated plants which were non‐mycorrhizal. We suspect that E. americanum is highly susceptible to water stress during the growing season and might rely on its mycorrhizas for water supply to a greater extent than for nutrient supply. Nutrient uptake might occur mainly in the autumn when arbuscules are at their most abundant.
Changes in microtubule arrays in symbiotic orchid protocorms during fungal colonization and senescence
Authors: UETAKE YUKARI , FARQUHAR MELISSA L. , PETERSON R. LARRY 
Published: March 2003

SUMMARYMicrotubule arrays were studied in Spiranthes sinensis (Pers.) Ames protocorms cultured in vitro either asymbiotically or symbiotically with the fungus Ceratobasidium cornigerum (Bourdot) Rogers by localizing β‐tubulin in hand sections observed with laser scanning confocal microscopy. Cortical microtubules present in uncolonized cells disappeared when cells became colonized by the fungus. However, microtubules were observed between the hyphae forming hyphal coils (pelotons) in colonized cells. In these cells a close relationship between pelotons, microtubules and nuclei was often observed, and microtubules associated with hyphae formed a net‐like structure through the pelotons. During senescence and condensation of the pelotons, microtubules were observed surrounding the pelotons, between collapsing hyphae and as circular profiles within the collapsed hyphal masses. In cells which contained completely collapsed hyphal masses and which were not recolonized, cortical microtubules reappeared and continued from the cell periphery through the hyphal remains to the collapsed hyphal masses. Microtubules associated with hyphae seemed to be involved in the condensation of hyphal masses in the host cells. Microtubules were also observed within hyphae, except in those which were collapsing or had collapsed.