bluuebunny/crossref_metadata_2025 huggingface dataset:
Prenatal age‐specific reference intervals for measuring all five digits of the fetal hand
Authors: Tovbin J. , Maymon R. , Tovbin L. , Dreazen E. , Bukovsky I. , Herman A.
Published: March 2003

Objective

To construct prenatal age‐specific reference intervals for measurement of five digits in normal fetuses.

Patients and Methods

Prospective cross‐sectional study of fetuses assessed at an antenatal ultrasound unit in a university‐affiliated general hospital. The study cohort comprised 302 pregnant women attending our clinic for routine fetal biometry or anomaly scan between December 1997 and June 2000. They all fulfilled the study inclusion criteria: singleton fetuses with normal anatomy, accurate gestational age and no medical complications of pregnancy. Each fetus was scanned once only and the finger measurements of one hand were obtained. Electronic calipers were placed on the outer margin of the proximal phalanx to the outer margin of the distal phalanx level. Those measurements and the relevant gestational age were registered in a computerized database.

Results

The linear increase of size of each of the five fingers was plotted across the evaluated range of gestation (P < 0.001; r
2 between 0.85 and 0.86 for fingers I to V). Tables showing the 5th, 50th and 95th centiles of finger lengths between 14 and 27 weeks' gestation were created based on the reference interval charts.

Conclusions

Second‐trimester measurement of all five digits of the fetal hand is feasible. This may assist in the evaluation of fetuses that are primarily suspected of having genetic abnormalities that might be expressed by deviation in finger length. Copyright © 2002 ISUOG
Can the degree of retrograde diastolic flow in abnormal umbilical artery flow velocity waveforms predict pregnancy outcome?
Authors: Brodszki J. , Hernandez‐Andrade E. , Gudmundsson S. , Dubiel M. , Mandruzzato G. P. , Laurini R. , Maršál K.
Published: March 2003

Objective

Reverse end‐diastolic flow is the most pathological type of the umbilical artery flow velocity waveform. We aimed to investigate whether additional prognostic information can be obtained from umbilical artery waveforms in cases with reverse end‐diastolic flow.

Subjects and methods

Umbilical artery Doppler velocity waveforms from 44 fetuses with reverse end‐diastolic flow were analyzed and the following parameters measured: the highest amplitude and the area below the maximum velocity curve of forward and reverse flow (A, B and C, D, respectively) and the duration of forward and reverse flow (Tc and Td, respectively). Ratios A/B, C/D and Tc/Td were calculated. The cut‐off values for A/B, C/D and Tc/Td with the best predictive values for perinatal death were established with the help of receiver operating characteristics curves. The three curves were compared with each other.

Results

Of the three ratios, A/B and C/D had the best capacity to predict perinatal death. Both ratios had acceptable sensitivities, specificities and positive predictive values. In this regard, A/B and C/D were comparable. The cut‐off values for A/B and C/D were 4.3 and 4.52, respectively. Survivors had significantly higher A/B and C/D ratios than non‐survivors (P = 0.0001 and 0.0003, respectively). Significantly more fetuses with A/B or C/D below the established cut‐off values had pulsations in the venous system (P < 0.05). In fetuses with a gestational age ≤210 gestational days the survival rate was significantly higher in those with A/B or C/D above the cut‐off values (P = 0.03 and 0.003, respectively).

Conclusions

The A/B or C/D ratio can be used for quantification of the reverse end‐diastolic flow waveforms in the umbilical artery and may offer additional information to the evaluation of fetal condition. Copyright © 2002 ISUOG
Chorionicity determination in twin pregnancies: how accurate are we?
Authors: Stenhouse E. , Hardwick C. , Maharaj S. , Webb J. , Kelly T. , Mackenzie F. M.
Published: March 2003

Objectives

To determine the accuracy of antenatal prediction of chorionicity in twin pregnancies in our institution.

Methods

Antenatal chorionicity was determined using the number of placental masses, the presence or absence of a twin peak sign and the fetal sex. The gestational age at assessment was documented. Postnatal diagnosis of chorionicity was determined by neonatal sex and placental pathology.

Results

Chorionicity was correctly determined in 95% of cases (n = 131); 91% of the monochorionic and 96% of the dichorionic pregnancies were correctly determined. If chorionicity was assessed prior to 14 weeks' gestation (n = 96) the correct diagnosis was made in all except one case.

Conclusions

Ultrasound assessment of chorionicity has a high sensitivity and specificity. This is further improved if the assessment is performed prior to 14 weeks' gestation. Copyright © 2002 ISUOG
Prenatal sonographic findings of thalamic cavernous angioma
Authors: Henrich W. , Stupin J. H. , Bühling K. J. , Bührer C. , Bassir C. , Dudenhausen J. W.
Published: March 2003

A cavernous angioma of the thalamus is a rare congenital brain tumor. We report the perinatal management and follow‐up to 2 years in a case diagnosed in utero at 37 weeks of gestation, and review the literature. Copyright © 2002 ISUOG
Fetal cardiac abnormalities identified prior to 14 weeks' gestation
Authors: Huggon I. C. , Ghi T. , Cook A. C. , Zosmer N. , Allan L. D. , Nicolaides K. H.
Published: March 2003

Objective

An increasing number of patients are presenting at early gestational age as being at high risk for congenital heart disease, as a result of ultrasound screening by nuchal translucency. The feasibility and accuracy of fetal echocardiography was assessed in a series of pregnancies studied before 14 weeks' gestation.

Methods

Echocardiography was attempted in 478 fetuses of crown–rump length 40.0–85.0 mm (median, 60.3 mm) with increased nuchal translucency, suspected abnormalities on routine scan or a family history of heart defect. The findings were related to results of autopsy, karyotyping, later scans and postnatal follow‐up.

Results

Satisfactory images were obtained transabdominally in 402/478 (84.1%) and transvaginally in a further 13 patients. Cardiac defects were confidently identified in 60 fetuses and abnormalities of uncertain significance (isolated ventricular or great artery disproportion, or tricuspid regurgitation) were observed in a further 49. Defects were suspected in an additional 20 fetuses, and 286 were passed as normal. The karyotype was subsequently demonstrated to be abnormal in 70/286 (24.5%) fetuses with normal echocardiograms, and in 94/129 (72.9%) with abnormal or suspicious cardiac findings. Validation of the scan findings was possible in 241 fetuses. Normal heart structure was confirmed in 204 fetuses, and previously unsuspected cardiac abnormalities revealed in nine. Heart defects were verified in 28 fetuses, but five of these had important additional findings. There were false positive findings in three fetuses.

Conclusions

Fetal echocardiography is feasible prior to 14 weeks' gestation. Cardiac defects, when present, may be identified or suspected in the majority of cases. In the risk group studied, heart defects were frequently a manifestation of chromosomal abnormality. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Prediction of fetal weight by ultrasound: the contribution of additional examiners
Authors: Gull I. , Fait G. , Har‐Toov J. , Kupferminc M. J. , Lessing J. B. , Jaffa A. J. , Wolman I.
Published: March 2003

Objectives

To assess the contribution of additional examiners to: the average discrepancy between estimated and actual fetal weights; the correlation between estimated and actual fetal weights; the reduction in major (> 10%) discrepancies between estimated and actual fetal weights.

Design

Three experienced sonographers independently measured fetal biparietal diameter, head circumference, abdominal circumference and femur length in 39 fetuses at term. The estimated fetal weights were calculated for each examiner. Fetal biometric measurements were analyzed to obtain the source of differences in estimations among the examiners. Discrepancy, correlation and number of major (> 10%) discrepancies between the estimated and actual fetal weights were calculated for each examiner, and the contribution of additional examiners was analyzed.

Results

The differences in measurements of the biparietal diameter and femur length were lower than those of the head and abdominal circumferences. For each of the three examiners, the average discrepancy between the estimated and actual fetal weights was 6.1%, 5.9% and 6.3%. When the estimation was based on two examiners, the discrepancy decreased to 4.8–5.6%. The contribution of a third examiner was nil. Major (> 10%) discrepancies between estimated fetal weight and actual birth weight were found in seven, eight and nine estimations of the examiners. Estimation by two examiners decreased the number of major discrepancies, and estimation by all three examiners further decreased by approximately 50% the number of major discrepancies between the estimated and actual fetal weights.

Conclusion

Measurements by multiple examiners changes only slightly the average number of discrepancies between estimated and actual fetal weights. However, the reduction in major (> 10%) discrepancies is statistically and clinically significant. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Blood redistribution in the fetal brain during chronic hypoxia
Authors: Dubiel M. , Gunnarsson G. Ö. , Gudmundsson S.
Published: March 2003

Background

Studies on blood flow velocity in the fetal middle cerebral artery have revealed signs of brain sparing in chronic hypoxia. These signs of brain sparing can disappear in the terminal case, but whether this applies to the whole brain or only parts of it is unknown.

Methods

Velocity waveforms of the middle cerebral, anterior cerebral and posterior cerebral arteries were recorded in 221 pregnancies complicated by pregnancy‐induced hypertension. The presence of brain sparing (pulsatility index < 2 standard deviations) was noted and correlated to outcome of pregnancy, including emergency operative intervention and/or neonatal distress.

Results

Signs of brain sparing in the anterior cerebral artery were found in 90 fetuses, and in the middle cerebral and posterior cerebral arteries in 52 and 65, respectively. Signs of brain sparing in the anterior cerebral artery showed the strongest relationship to adverse perinatal outcome. The anterior cerebral artery was the only vessel in which signs of brain sparing were predictive of perinatal mortality.

Conclusions

Velocimetry of the anterior cerebral artery appears to be superior to that of the middle cerebral and posterior cerebral arteries as a means to predict adverse perinatal outcome. Anterior cerebral artery brain sparing may therefore be less transitory than sparing in the middle cerebral and posterior cerebral arteries, possibly suggesting that the frontal lobes are spared longer than the lateral and occipital regions of the fetal brain.
Impact of a multiparameter, ultrasound‐based triage on surgical management of adnexal masses
Authors: Berlanda N. , Ferrari M. M. , Mezzopane R. , Boero V. , Grijuela B. , Ferrazzi E. , Pardi G.
Published: March 2003

Objective

To prospectively evaluate the accuracy of a multiparameter, ultrasound‐based triage and its impact on surgical management of adnexal masses.

Methods

Masses evaluated as normal according to Ferrazzi's sonographic morphological score were considered as being at low risk of malignancy and eligible for laparoscopic treatment without further evaluation. Masses evaluated as abnormal, but without additional risk factors such as ascites, diameter ≥ 10 cm, bilaterality, immobility, resistance index ≤ 0.6 and serum CA 125 > 35 IU/mL were considered at moderate risk and eligible for laparoscopic evaluation and treatment. Masses with abnormal morphological score and any of these additional risk factors were considered at high risk and treated by laparotomy. The results of pathological examination were obtained for each mass.

Results

Two hundred and four (87%) masses were benign and 30 (13%) were malignant. Among 182 low‐risk, 19 moderate‐risk and 33 high‐risk masses, the odds of malignancy were 1 : 90, 1 : 18 and 4.5 : 1, respectively. To calculate the diagnostic accuracy of this algorithm, low‐ and moderate‐risk groups were considered together: the sensitivity was 90%, specificity 97%, positive predictive value 82% and negative predictive value 99%. The new algorithm was significantly more accurate than was morphological score alone (P = 0.0002). Ninety‐six percent of benign masses were treated by laparoscopy. All three patients with malignant masses that were incorrectly assigned to laparoscopy underwent laparoscopic adnexectomy and frozen section.

Conclusions

The accuracy of this new algorithm was higher than that of the sonographic morphological scoring system alone. In the present series, it allowed the treatment by laparoscopy of 96% of benign adnexal masses without mismanagement of any cases of ovarian cancer.
On the morphology of the brachial plexus of the platypus (Ornithorhynchus anatinus) and the echidna (Tachyglossus aculeatus)
Authors: KOIZUMI MASAHIRO , SAKAI TATSUO
Published: March 2003

Four forelimbs of 3 platypuses and 3 forelimbs of 2 echidnas were examined to study the precise form of the brachial plexus and to clarify the structural characteristics of the brachial plexus in phylogeny. The spinal components contributing to the plexus (C4–T2) and the formation patterns of the 3 trunks of the plexus were the same as those generally observed in mammals. In the cranial half of the brachial plexus from C4, 5 and 6 in monotremes, division into the ventral bundle (lateral cord) and dorsal bundle (axillary nerve) is clear, as in other mammals. However, for monotremes, in the caudal half of the plexus from C7 and T1 (+T2) and the nerves arising from the caudal plexus there is no definite division into the ventral and dorsal bundles, which distribute to the flexor and extensor parts of the forelimbs, respectively. The lower trunk of the monotreme brachial plexus forms a cord which contains both ventral and dorsal components. This characteristic diverges from the generally accepted idea that the tetrapod limb plexus is divided clearly into 2 layers: a dorsal layer for extensors and a ventral layer for flexors of the limb. Considering the incomplete dorsoventral division of forelimb nerves in some reptiles and urodeles, the caudal half of the monotreme brachial plexus has characteristics in common with those of lower tetrapods.
An ultrastructural study of cartilage resorption at the site of initial endochondral bone formation in the fetal mouse mandibular condyle
Authors: SHIBATA SHUNICHI , SUZUKI SHOICHI , YAMASHITA YASUO
Published: March 2003

An ultrastructural study was undertaken on cartilage resorption at the site of initial endochondral bone formation in the mouse mandibular condyle on d 16 of pregnancy. After resorbing the bone collar, the osteoclasts extended their cell processes into the cartilage matrix and made contact with hypertrophic chondrocytes. By means of cell processes or vacuolar structures, these osteoclasts entrapped the calcified cartilage matrices, cell debris, and the degraded uncalcified cartilage matrices. In particular, since the calcified cartilage matrices were sometimes seen to be disrupted within the osteoclastic vacuolar structures, they were probably disposed of by the osteoclasts. Invading endothelial cells giving rise to capillaries also directly surrounded the degraded uncalcified cartilage matrices and small deposits of cell debris. In addition, hypertrophic chondrocytes that had attached to or were in the process of attaching to the invading osteoclasts often enclosed the small calcified cartilage matrices. Other cell types that have often been reported in other regions of cartilage resorption were not seen at the site of initial endochondral bone formation in this study. Our findings in relation to cartilage resorption may therefore represent unique features of the site of initial endochondral bone formation site. We consider that the manner of cartilage resorption is likely to vary by site, age, and species.
Specialised sympathetic neuroeffector associations in rat iris arterioles
Authors: SANDOW SHAUN L. , WHITEHOUSE DREW , HILL CARYL E.
Published: March 2003

Vascular sympathetic neuroeffector associations have been examined in rat iris arterioles using serial section electron microscopy and reconstruction techniques. Examination of random sections showed that, of all profiles of varicosities (199) seen to lie closer than 4 μm to vascular smooth muscle cells, only a small proportion (29/199) were found in close association with vascular smooth muscle cells, where adjacent membranes were separated by less than 100 nm. However, serial section examination, from intervaricose region to intervaricose region, of 79 varicosities similarly observed lying within 4 μm of vascular smooth muscle cells showed that 54 formed close associations with vascular smooth muscle cells. In serial sections, all these varicosities were also closely associated with melanocytes and of the 25 remaining varicosities, 22 formed close associations with melanocytes alone, whilst 3 did not come into close association with any effector cell. The increased observation of close associations with vascular smooth muscle cells in serial sections, compared with random sections, is consistent with the demonstration that the area of contact only occupies, on average, a small percentage (5%) of the total surface area of the varicosity as seen in the 3‐dimensional reconstructions. In both random and serial sections, close associations were observed between varicosities and vascular smooth muscle cells or melanocytes irrespective of whether fibres were present singly or in small nerve bundles. Three‐dimensional reconstruction of associations of varicosities and vascular smooth muscle cells demonstrated several common features, such as accumulations of synaptic vesicles and loss of Schwann cell covering at the region of membrane facing the effector cell. The similarity in the appearance of the neuroeffector association seen in this study and those described in previous studies provides evidence for the existence of a common sympathetic neuroeffector association, irrespective of the receptor subtype involved in neurotransmission.
Advances in three‐dimensional diagnostic radiology
Authors: TER HAAR ROMENY BART M. , ZUIDERVELD KAREL J. , VAN WAES PAUL F. G. M. , VAN WALSUM THEO , VAN DER WEIJDEN REMKO , WEICKERT JOACHIM , STOKKING RIK , WINK ONNO , KALITZIN STILIYAN , MAINTZ TWAN , ZONNEVELD FRANS , VIERGEVER MAX A.
Published: March 2003

The maturity of current 3D rendering software in combination with recent developments in computer vision techniques enable an exciting range of applications for the visualisation, measurement and interactive manipulation of volumetric data, relevant both for diagnostic imaging and for anatomy. This paper reviews recent work in this area from the Image Sciences Institute at Utrecht University. The processes that yield a useful visual presentation are sequential. After acquisition and before any visualisation, an essential step is to prepare the data properly: this field is known as ‘image processing’ or ‘computer vision’ in analogy with the processing in human vision. Examples will be discussed of modern image enhancement and denoising techniques, and the complex process of automatically finding the objects or regions of interest, i.e. segmentation. One of the newer and promising methodologies for image analysis is based on a mathematical analysis of the human (cortical) visual processing: multiscale image analysis. After preprocessing the 3D rendering can be acquired by simulating the ‘ray casting’ in the computer. New possibilities are presented, such as the integrated visualisation in one image of (accurately registered) datasets of the same patient acquired in different modality scanners. Other examples include colour coding of functional data such as SPECT brain perfusion or functional magnetic resonance (MR) data and even metric data such as skull thickness on the rendered 3D anatomy from MR or computed tomography (CT). Optimal use and perception of 3D visualisation in radiology requires fast display and truly interactive manipulation facilities. Modern and increasingly cheaper workstations (<$10000) allow this to be a reality. It is now possible to manipulate 3D images of 2563 at 15 frames per second interactively, placing virtual reality within reach. The possibilities of modern workstations become increasingly more sophisticated and versatile. Examples presented include the automatic detection of the optimal viewing angle of the neck of aneurysms and the simulation of the design and placement procedure of intra‐abdominal aortic stents. Such developments, together with the availability of high‐resolution datasets of modern scanners and data such as from the NIH Visible Human project, have a dramatic impact on interactive 3D anatomical atlases.
Determination of a standard site for the measurement of bone mineral density of the human calcaneus
Authors: BURSTON B. , McNALLY D. S. , NICHOLSON H. D.
Published: March 2003

Ultrasound of the calcaneus may be used as a cheap, ionising radiation‐free and easy to use indicator of skeletal status, and hence of osteoporotic fracture risk. At present ultrasound is not widely used as it suffers from high precision errors. As ultrasound parameters are determined in part by bone mineral density (BMD), an increase in the accuracy and precision of BMD measurements should reduce the precision error associated with ultrasound measurements. The aim of this study was to define an anatomical site on the calcaneus at which accurate and precise measurements of BMD can be made. Ten dry calcanei and 10 cadaveric feet were scanned using a DXA scanner; 9 anatomically defined regions (1 cm2) were selected in the posterior part of the calcaneus for analysis. The centre of region 1 was positioned halfway along the line joining the anterior border of the calcaneal tubercle and the peak of the posterior superior tubercle, and the remaining 8 regions were placed around this central area. The BMD in these 9 regions was compared with the whole bone BMD and the variability of BMD within each of the 9 regions was measured. The reproducibility of the technique was assessed by taking 10 repeated measurements of 2 bone and 2 cadaveric specimens, each specimen being removed and repositioned between measurements. Region 1 was found to be the most representative of total BMD in cadaveric feet. This region also showed the least variability of BMD and consistently gave the lowest coefficients of variation in the reproducibility study both in the bone and the cadaveric specimens. This region is hence the most suitable site on the calcaneus for measuring absolute values of and changes in BMD. The surface position of region 1 was found to be consistently 5/9 along the line at 45° to the vertical, from the lateral malleolus to the heel. The identification of the surface location of region 1 relative to anatomical landmarks of the foot has enabled the same anatomical site to be measured in all subjects. This allows meaningful intersubject comparisons to be made. Preliminary data suggest that precision errors using ultrasound are also reduced when measurements are taken at this region of the calcaneus. The reduction in the precision error of ultrasound assessment of skeletal status may provide a cheap and safe way to identify individuals at risk from osteoporotic fracture.
Immunolocalisation of vascular endothelial growth factor (VEGF) in human neonatal growth plate cartilage
Authors: HORNER A. , BISHOP N. J. , BORD S. , BEETON C. , KELSALL A. W. , COLEMAN N. , COMPSTON J. E.
Published: March 2003

Angiogenesis is essential for the replacement of cartilage by bone during growth and repair. In order to obtain a better understanding of the mechanisms regulating vascular invasion at sites of endochondral ossification we have investigated the expression of the endothelial cell‐specific mitogen, vascular endothelial growth factor (VEGF), by chondrocytes in human neonatal growth plates. VEGF was absent from chondrocytes in the resting zone and only weakly expressed by occasional chondrocytes in the proliferating region. In the hypertrophic zone the number of chondrocytes stained and the intensity of staining for VEGF increased with chondrocyte hypertrophy, maximum expression of VEGF being observed in chondrocytes in the lower hypertrophic and mineralised regions of the cartilage. These observations provide the first demonstration of the presence of VEGF in situ in developing human bone and are consistent with in vitro observations demonstrating the upregulation of proangiogenic growth factor production with increasing chondrocyte hypertrophy. The presence of numerous small blood vessels and vascular structures in the subchondral region where VEGF expression was maximal indicates that VEGF produced by hypertrophic chondrocytes may play a key role in the regulation of vascular invasion of the growth plate.
Glucocorticoids induce glutamine synthetase in folliculostellate cells of rat pituitary glands in vivo and in vitro
Authors: SHIRASAWA NOBUYUKI , YAMANOUCHI HIROSHI
Published: March 2003

Glutamine synthetase (GS) is a glucocorticoid‐inducible enzyme that has a key role for glutamate metabolism in the central and peripheral nervous system. In this study GS activity was measured and the amount of immunoreactive GS (ir‐GS) cells in the rat anterior pituitary gland was quantified as a function of age. In addition, the effects of GS inhibitors, glucocorticoid administration, and adrenalectomy on GS activity were examined. Some of the ir‐GS cells were also immunoreactive for S100 protein (ir‐S100) which is a known marker for folliculostellate cells (FS) in the anterior pituitary. FS cells expressing GS were first detected in 3‐d‐old rats, and this cell population, expressed as the immunostained cell area divided by a standard unit area, increased as a function of age. The percentages of FS cells also expressing GS were 0.2, 6.4, 25 and 74% at 3 d, 30 d, 60 d and 2 y of age, respectively. GS enzyme activity also increased in parallel with the increase of ir‐GS cell population maturation. The subcutaneous injection of methionine sulphoximine, a GS and γ‐glutamylcysteine synthetase inhibitor, reduced pituitary GS activity by 83%, but increased the population of ir‐GS cells 3.5‐fold in 30‐d‐old rats. Buthionine sulphoximine, a specific inhibitor of γ‐glutamylcysteine synthetase, had little effect on GS activity or the ir‐GS cell population. Neither methionine sulphoximine nor buthionine sulphoximine changed the population of ir‐S100 protein cells (FS cells). Dexamethasone and hydrocortisone increased the population of ir‐GS cells by 3.1 and 4.2‐fold, respectively, within 12 h after administration. A significant increase of GS activity due to the injection of glucocorticoids was observed in the anterior pituitary, but not in the brain, retina or liver of immature rats. Adrenalectomy did not cause decrease of pituitary GS activity, and dexamethasone administration increased GS activity in both adrenalectomised and intact rats. In the monolayer culture of anterior pituitary cells, glucocorticoids increased GS activity by ×1.5, and methionine sulphoximine reduced the activity by over 94%. These results demonstrate that GS in folliculostellate cells is a glucocorticoid‐inducible enzyme in vivo and in vitro, and that the age‐dependent increase of GS activity is independent of endogenous adrenal glucocorticoids.
Peptidergic hormones and neuropeptides, and aminergic neurotransmitters of the pancreatic islets of the Houbara bustard (Chlamydotis undulata)
Authors: MENSAH‐BROWN E. P. K. , BAILEY T. A. , PALLOT D. J. , GARNER A.
Published: March 2003

Immunoreactivity to insulin (Ins), somatostatin (Som), glucagon (Glu) and pancreatic polypeptide (PP) was found in 70%, 22%, 15% and 11% respectively of Houbara pancreatic endocrine islet cells. Whilst Ins occurred centrally and SOM was observed both in peripherally and centrally located islets, the other hormones were localised in peripheral islet cells; Som was also observed in neuronal cell bodies and nerve fibres. In addition, the islet cells contained substance P (SP) (65%) in the centre and vasoactive intestinal polypeptide (VIP) (2%) at the periphery. Immunoreactivity to choline acetyltransferase (ChAT), VIP and galanin (Gal) occurred in the walls of blood vessels located mainly at the periphery of islets. Occasionally, VIP and Gal immunoreactive varicose nerve terminals and ChAT immunoreactive cell bodies were also observed in the centre of islets. SP neuronal cell bodies were not observed but prominent SP immunoreactive varicose terminals were discernible in capillary walls within the islets. Neuropeptide Y (NPY) immunoreactive neurons were detected in neuronal cell bodies located mainly peripherally. Neuronal nitric oxide synthase (nNOS) immunoreactivity occurred in neuronal cell bodies and nerve fibres mainly at the periphery and also in centrally located islet endocrine cells. Immunoreactivity to tyrosine hydroxylase (TH) was similar in distribution to that of ChAT. In comparison with other avian species, the islets of the dorsal pancreatic lobe of the bustard contain all the peptidergic hormones normally present in the islets of other avian species, but are not segregated into dark A and light B cells. Many of the insulin containing cells also contained SP. The islets also contained several neuropeptides which are probably involved in their regulation.
Neonatal pulmonary hypertension prevents reorganisation of the pulmonary arterial smooth muscle cytoskeleton after birth
Authors: HALL SUSAN M. , GORENFLO MATTIAS , READER JAYNE , LAWSON DURWARD , HAWORTH SHEILA G.
Published: March 2003

The pulmonary arterial smooth muscle cell (SMC) cytoskeleton was studied in tissue from 36 piglets aged from within 5 min of birth to 21 d of age, and in 8 adults. An additional 16 piglets were made pulmonary hypertensive by exposure to hypobaric hypoxia (50.8 kPa) for 3 d. In conduit intrapulmonary elastic arteries α, β and γ actin, the 204, 200 and 196 kDa myosin heavy chain (MHC) isoforms and vinculin were localised by immunohistochemistry. The total actin content, the proportion of monomeric to filamentous α and γ actin and changes in the proportions of the MHC isoforms were determined biochemically. Dividing SMCs were localised and quantified using Ki‐67. We found a transient reduction in immunohistochemical expression of γ actin, 204 kDa MHC isoform and vinculin at 3 and 6 d in the inner media, associated with a transient increase in Ki‐67 labelling. The actin content also decreased at 3 and 6 d (P < 0.05), but there was a postnatal, permanent increase in monomeric actin, first the α then the γ isoform. The relative proportions of the MHC isoforms did not change between birth and adulthood in elastic pulmonary arteries but in muscular arteries the 200 kDa isoform increased between 14 d and adulthood. Pulmonary hypertension prevented both the immunohistochemical changes and the postnatal burst of SMC replication and prevented the transient postnatal reduction in actin content. These findings suggest that rapid remodelling of the actin cytoskeleton is an essential prerequisite of a normal postnatal fall in pulmonary vascular resistance.
Widespread expression of tartrate‐resistant acid phosphatase (Acp 5) in the mouse embryo
Authors: HAYMAN ALISON R. , BUNE ALISON J. , COX TIMOTHY M.
Published: March 2003

Tartrate‐resistant acid phosphatase (TRAP, Acp 5) is considered to be a marker of the osteoclast and studies using ‘knockout’ mice have demonstrated that TRAP is critical for normal development of the skeleton. To investigate the distribution of TRAP in the mammalian embryo, cryostat sections of 18 d murine fetuses were examined by in situ hybridisation, immunohistochemistry and histochemical reactions in situ. Abundant expression of TRAP mRNA was observed in the skin and epithelial surfaces of the tongue, oropharynx and gastrointestinal tract including the colon, as well as the thymus, ossifying skeleton and dental papillae. TRAP protein was identified at the same sites, but the level of expression in the different tissues did not always correlate with apparent enzyme activity. The findings indicate that abundant TRAP expression is not confined to osteoclasts in bone, but occurs in diverse tissues harbouring cells of bone marrow origin, including dendritic cells and other cells belonging to the osteoclast/macrophage lineage.
GABAB and group I metabotropic glutamate receptors in the striatopallidal complex in primates
Authors: SMITH YOLAND , CHARARA ALI , HANSON JESSE E. , PAQUET MARYSE , LEVEY ALLAN I.
Published: March 2003

Glutamate and GABA neurotransmission is mediated through various types of ionotropic and metabotropic receptors. In this review, we summarise some of our recent findings on the subcellular and subsynaptic localisation of GABAB and group I metabotropic glutamate receptors in the striatopallidal complex of monkeys. Polyclonal antibodies that specifically recognise GABABR1, mGluR1a and mGluR5 receptor subtypes were used for immunoperoxidase and pre‐embedding immunogold techniques at the light and electron microscope levels. Both subtypes of group I mGluRs were expressed postsynaptically in striatal projection neurons and interneurons where they aggregate perisynaptically at asymmetric glutamatergic synapses and symmetric dopaminergic synaptic junctions. Moreover, they are also strongly expressed in the main body of symmetric synapses established by putative intrastriatal GABAergic terminals. In the globus pallidus, both receptor subtypes are found postsynaptically in the core of striatopallidal GABAergic synapses and perisynaptically at subthalamopallidal glutamatergic synapses. Finally, extrasynaptic labelling was commonly seen in the globus pallidus and the striatum.

Moderate to intense GABABR1 immunoreactivity was observed in the striatopallidal complex. At the electron microscope level, GABABR1 immunostaining was commonly found in neuronal cell bodies and dendrites. Many striatal dendritic spines also displayed GABABR1 immunoreactivity. Moreover, GABABR1‐immunoreactive axons and axon terminals were frequently encountered. In the striatum, GABABR1‐immunoreactive boutons resembled terminals of cortical origin, while in the globus pallidus, subthalamic‐like terminals were labelled. Pre‐embedding immunogold data showed that postsynaptic GABABR1 receptors are concentrated at extrasynaptic sites on dendrites, spines and somata in the striatopallidal complex, perisynaptically at asymmetric synapses and in the main body of symmetric striatopallidal synapses in the GPe and GPi. Consistent with the immunoperoxidase data, immunoparticles were found in the presynaptic grid of asymmetric synapses established by cortical‐ and subthalamic‐like glutamatergic terminals.

These findings indicate that both GABA and glutamate metabotropic receptors are located to subserve various modulatory functions of the synaptic transmission in the primate striatopallidal complex. Furthermore, their pattern of localisation raises issues about their roles and mechanisms of activation in normal and pathological conditions. Because of their ‘modulatory’ functions, these receptors are ideal targets for chronic drug therapies in neurodegenerative diseases such as Parkinson's disease.
Compartments of the adult parasellar region
Authors: WENINGER WOLFGANG J. , PRAMHAS DELIO
Published: March 2003

In the infant the region lateral to the sella turcica which is traditionally termed the ‘cavernous sinus’ is composed of 3 individual compartments. The aim of this study was to demonstrate a similar compartmentation of the adult cavernous sinus and to identify and quantify the adipose bodies which are located within the compartments. The region of the cavernous sinus in 136 adults was analysed by microdissection and histology. We demonstrate that in 66% of the cavernous sinus in adults is composed of at least 2 compartments and in 22% it is made up of 3. Assimilating the renaming in infants we termed the compartments ‘pterygopalatine’, ‘orbital’ and ‘lateral sellar’. The pterygopalatine and orbital compartments are connected with extracranial tissue spaces via the superior orbital fissure and contain characteristic adipose bodies. Exact topographic descriptions and measurements of the compartments and their adipose bodies are provided. Our study clearly defines compartmentation of the adult parasellar space in most individuals and thus changes the anatomical view of this space. The direct connection of 2 of these compartments with extracranial tissue spaces and the measurements of their adipose bodies are of interest for surgeons and neuroradiologists.
Carbohydrate moieties of the interstitial and glandular tissues of the amphibian Pleurodeles waltl testis shown by lectin histochemistry
Authors: SÁEZ FRANCISCO JOSÉ , MADRID JUAN FRANCISCO , APARICIO RAQUEL , HERNÁNDEZ FRANCISCO , ALONSO EDURNE
Published: March 2003

The amphibian testis is a useful model because of its zonal organisation in lobules, distributed along the cephalocaudal axis, each containing a unique germ cell type. Sperm empty lobules form the so‐called glandular tissue at the posterior region of the gonad. Androgen production is limited to the cells of the interstitial tissue surrounding lobules with spermatozoa bundles and to the cells of the glandular tissue. In this work, we have studied the distribution of terminal carbohydrate moieties of N‐ and O‐linked oligosaccharides in the interstitial and glandular tissue of the Pleurodeles waltl testis, by means of 14 lectins combined with chemical and enzymatic deglycosylation pretreatment. Some differences in glycan composition between the interstitial and the glandular tissue have been detected. Thus in both tissues, N‐linked oligosaccharides contained mannose, Gal(β1,4)GlcNAc, and Neu5Ac(α2,3)Gal(β1,4)GlcNAc, while O‐linked oligosaccharides contained Con A‐positive mannose, Gal(β1,3)GalNAc, Gal(β1,4)GlcNAc, Neu5Ac(α2,3)Gal(β1,4)GlcNAc, and WGA‐positive GlcNAc. Fucose was also detected in both tissues. However, GlcNAc on N‐linked oligosaccharides and GalNAc and Neu5Ac(α2,6)Gal/GalNAc on both N‐ and O‐linked oligosaccharides were found only in the interstitial tissue. As glandular tissue cells arise from the innermost cells of interstitial tissue that surround lobules, the differences in the glycan composition of interstitial and glandular tissue shown in this work may be related to the start of androgen synthesis when steroid hormone (SH)‐secreting cells develop.
Biphalangeal fifth toe: an increasingly common variant?
Authors: GEORGE M.
Published: March 2003

The presence of 2 phalanges in the 5th toe was first described by Leonardo da Vinci in 1492 (O’Malley & Saunders, 1952) and is recognised as a normal variant. It is probably a true anatomical variant resulting from incomplete segmentation rather than the result of phalangeal fusion (Venning, 1960; Le Minor, 1995) and has been noted to be present in fetuses from as early as 12 wk (Venning, 1960). This variant (and the much rarer 2 biphalangeal 2nd–4th toes) is an exclusively human phenomenon suggesting it is a response to bipedalism (Le Minor, 1995). Various investigators have reported the incidence of the 2 phalanged 5th toe of populations as between 35.5% and 80.4% with the lower values being seen in Europeans and the higher in Japanese (Venning, 1960; Thompson & Chang, 1995). Our study compared foot radiographs in the old and young to see if there was any difference in incidence.
Asymmetry in the epithalamus of vertebrates
Authors: CONCHA MIGUEL L. , WILSON STEPHEN W.
Published: March 2003

abstract

The epithalamus is a major subdivision of the diencephalon constituted by the habenular nuclei and pineal complex. Structural asymmetries in this region are widespread amongst vertebrates and involve differences in size, neuronal organisation, neurochemistry and connectivity. In species that possess a photoreceptive parapineal organ, this structure projects asymmetrically to the left habenula, and in teleosts it is also situated on the left side of the brain. Asymmetries in size between the left and right sides of the habenula are often associated with asymmetries in neuronal organisation, although these two types of asymmetry follow different evolutionary courses. While the former is more conspicuous in fishes (with the exception of teleosts), asymmetries in neuronal organisation are more robust in amphibia and reptiles. Connectivity of the parapineal organ with the left habenula is not always coupled with asymmetries in habenular size and/or neuronal organisation suggesting that, at least in some species, assignment of parapineal and habenular asymmetries may be independent events.

The evolutionary origins of epithalamic structures are uncertain but asymmetry in this region is likely to have existed at the origin of the vertebrate, perhaps even the chordate, lineage. In at least some extant vertebrate species, epithalamic asymmetries are established early in development, suggesting a genetic regulation of asymmetry. In some cases, epigenetic factors such as hormones also influence the development of sexually dimorphic habenular asymmetries. Although the genetic and developmental mechanisms by which neuroanatomical asymmetries are established remain obscure, some clues regarding the mechanisms underlying laterality decisions have recently come from studies in zebrafish. The Nodal signalling pathway regulates laterality by biasing an otherwise stochastic laterality decision to the left side of the epithalamus. This genetic mechanism ensures a consistency of epithalamic laterality within the population. Between species, the laterality of asymmetry is variable and a clear evolutionary picture is missing. We propose that epithalamic structural asymmetries per se and not the laterality of these asymmetries are important for the behaviour of individuals within a species. A consistency of the laterality within a population may play a role in social behaviours between individuals of the species.
Morphogenesis and evolution of vertebrate appendicular muscle
Authors: HAINES LYNN , CURRIE PETER D.
Published: March 2003

abstract

Two different modes are utilised by vertebrate species to generate the appendicular muscle present within fins and limbs. Primitive Chondricthyan or cartilaginous fishes use a primitive mode of muscle formation to generate the muscle of the fins. Direct epithelial myotomal extensions invade the fin and generate the fin muscles while remaining in contact with the myotome. Embryos of amniotes such as chick and mouse use a similar mechanism to that deployed in the bony teleost species, zebrafish. Migratory mesenchymal myoblasts delaminate from fin/limb level somites, migrate to the fin/limb field and differentiate entirely within the context of the fin/limb bud. Migratory fin and limb myoblasts express identical genes suggesting that they possess both morphogenetic and molecular identity. We conclude that the mechanisms controlling tetrapod limb muscle formation arose prior to the Sarcopterygian or tetrapod radiation.
Trabecular trajectory in the articular processes of the human fourth cervical vertebra
Authors: HERRERA M. , PANCHÓN A. , PEREZ‐BACETE M.
Published: March 2003

The articular processes (AP) of the neural arch have been implicated in weight transmission through the cervical spine. To analyse the mechanism of weight transmission in the AP, we studied the direction of forces within it, in particular, the pattern of trabecular trajectories. Twenty‐two AP from C4 vertebrae were studied in anatomical sections, and corresponding photoelastic models from selected sections were constructed and analysed. Anatomical and photoelastic findings show the subarticular spongiosa of the superior articular process (SAP) to be orthogonally arranged with vertical and oblique trabeculae in the direction of compressive forces and additional trabeculae always oriented perpendicular to the former. Vertical and oblique trabeculae are divided into rostral, middle and posterior groups. Rostral and middle trabeculae end in the anterior wall of the SAP and the transitional zone with the pedicle. Posterior trabeculae end in the subarticular spongiosa of the inferior articular process (IAP). The findings relating to trabecular trajectories in the SAP differ from previous descriptions and instead suggest that a part of the weight forces distributed within the AP transmit to the subchondral zone of the IAP. Knowledge of the trajectorial architecture of the AP may contribute to refining finite element analytical models for investigating its weight‐bearing function.
Early nephron formation in the developing mouse kidney
Authors: BARD JONATHAN B. L. , GORDON ADELE , SHARP LINDA , SELLERS WILLIAM I.
Published: March 2003

This paper reports 3‐dimensional confocal microscopy observations on how nephrogenic aggregates form from the NCAM‐ and Pax2‐positive caps (4–5 cells deep) of condensed metanephric mesenchyme surrounding the duct tips of the mouse kidney. Aggregates of 6–8 cells are first seen at ∼E12.5–12.75 immediately proximal to this cap, closely abutting the duct surface. As the tip advances, NCAM expression is maintained in the cap but is otherwise restricted to aggregates whose cells rapidly epithelialise, forming tubules that invade the duct epithelium. Pax2 expression studies shows how the rind of nephrogenic blastemal cells forms: as duct tips extend towards the kidney surface, the associated Pax2+ cells form patches of cells on the kidney surface. These observations revise our knowledge of the timing and process of nephron initiation.
Fibrocartilage at the entheses of the suprascapular (superior transverse scapular) ligament of man—a ligament spanning two regions of a single bone
Authors: MORIGGL B. , JAX P. , MILZ S. , BÜTTNER A. , BENJAMIN M.
Published: March 2003

The suprascapular ligament converts the suprascapular notch into a foramen separating the vessels and nerve of the same name. It connects 2 regions of the same bone and does not cross any joint, and no mechanical function has yet been attributed to it. Nevertheless, variations in its thickness and length, and its tendency to ossify, suggest that the ligament responds to changes in mechanical load. This should be reflected in the composition of the extracellular matrix. The primary purpose of the present study is to demonstrate that the suprascapular ligament has fibrocartilaginous entheses (i.e. insertion sites), even though there is no obvious change in insertional angle that directly results from joint movement. Such a change is more typical of tendons or ligaments that cross highly mobile joints. The complete ligament (including both entheses) was removed from 7 cadavers shortly after death and fixed in 90% methanol. Cryosections were immunolabelled with a panel of monoclonal antibodies against collagens (types I, II, III, VI), glycosaminoglycans (chondroitin 4 sulphate, chondroitin 6 sulphate, dermatan sulphate and keratan sulphates), proteoglycans (aggrecan and versican) and link protein. Both entheses were strongly fibrocartilaginous, and a moderately fibrocartilaginous matrix was also detected throughout the remainder of the ligament. The extracellular matrix of both entheses labelled strongly for type II collagen, aggrecan and link protein. The fibrocartilaginous character of the entheses suggests that the insertion sites of the ligament are subject to both compressive and tensile loading and are regions of stress concentration. This in turn probably reflects the complex shape of the scapula and the presence of a conspicuous indentation (the suprascapular notch) near the ligament. The loading patterns may reflect either the attachment of muscles and/or the forces transmitted to the suprascapular ligament from the neighbouring coracoclavicular ligament.