bluuebunny/crossref_metadata_2025 huggingface dataset:
Congenital lobar emphysema – the disappearing chest mass: antenatal ultrasound appearance
Authors: Quinton A. E. , Smoleniec J. S.
Published: March 2003

Prenatal diagnosis of congenital lobar emphysema is rarely reported in the literature. This case presents a fetus with an echogenic lung diagnosed at 18 weeks' gestation, that resolved completely during the pregnancy. This case is unique in that sonographic increased echogenicity was first noted at 18 weeks' gestation and had disappeared by 29 weeks' gestation. The diagnosis was made in the postnatal period as a result of follow up of the prenatal findings. This case reinforces the importance of continuing postnatal investigations of prenatal sonographic abnormalities even when they appear to have disappeared. A discussion of the causes of congenital lobar emphysema is presented. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
Bilateral congenital diaphragmatic hernia: diagnostic clues at fetal sonography
Authors: Song M. S. , Yoo S.‐J. , Smallhorn J. F. , Mullen J. B. M. , Ryan G. , Hornberger L. K.
Published: March 2003

Bilateral congenital diaphragmatic hernia is a rare, life‐threatening malformation. We describe a case of bilateral Bochdalek hernia diagnosed prenatally. The sonographic clues to the diagnosis were anterior displacement of the heart with relatively minimal lateral shift. The definitive diagnosis was made by demonstrating the liver in the right thorax and bowel loop and stomach in the left thorax. Color and power Doppler demonstrated the hepatic vessels embracing both sides of the heart from behind. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
Retrospective prenatal diagnosis of scimitar syndrome aided by three‐dimensional power Doppler imaging
Authors: Michailidis G. D. , Simpson J. M. , Tulloh R. M. R. , Economides D. L.
Published: March 2003

Scimitar syndrome is a rare malformation of the arterial supply and venous drainage of the lung. We report the case of a fetus that presented with cardiac asymmetry and malposition of the fetal heart. Postnatally, scimitar syndrome was confirmed at cardiac catheterization. Retrospective reconstruction of three‐dimensional power Doppler volumes, obtained during fetal life, allowed direct visualization of the abnormal aortopulmonary collateral vessel. This had not been seen on conventional scans. This case demonstrates many of the strengths of three‐dimensional sonographic techniques for the delineation of complex vascular anatomy. It confirms that a prospective diagnosis of scimitar syndrome should be possible during fetal life. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
Evaluation of prenatal diagnosis of congenital heart diseases by ultrasound: experience from 20 European registries
Authors: Garne E. , Stoll C. , Clementi M.
Published: March 2003

Objectives

To evaluate prenatal diagnosis of congenital heart diseases by ultrasound investigation in well‐defined European populations.

Design

Data from 20 registries of congenital malformations in 12 European countries were included. The prenatal ultrasound screening programs in the countries ranged from no routine screening to three ultrasound investigations per patient routinely performed.

Results

There were 2454 cases with congenital heart disease with an overall prenatal detection rate of 25%. Termination of pregnancy was performed in 293 cases (12%). There was considerable variation in prenatal detection rate between regions, with the lowest detection rates being in countries without ultrasound screening (11%) and in Eastern European countries (Croatia, Lithuania and Ukraine; 8%). In Western European countries with ultrasound screening, detection rate ranged from 19–48%. There was a significant difference in prenatal detection rate and proportion of induced abortions between isolated congenital heart disease and congenital heart disease associated with chromosome anomalies, multiple malformations and syndromes (P < 0.0001). There were 1694 cases with isolated congenital heart disease of which 16% were diagnosed prenatally. Malformations affecting the size of the ventricles were detected prenatally in half of the cases.

Conclusions

Prenatal detection rate of congenital heart disease varies significantly between countries even with the same screening recommendations. The presence of associated malformations significantly increases the prenatal detection rate. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
Prenatal diagnosis of mosaic trisomy 8 in a fetus with normal nuchal translucency thickness and reversed end‐diastolic ductus venosus flow
Authors: Campbell S. , Mavrides E. , Prefumo F. , Presti F. , Carvalho J. S.
Published: March 2003

We report a case of the prenatal diagnosis of trisomy 8 in a fetus presenting with normal nuchal translucency of 0.8 mm and reversed end‐diastolic ductus venosus blood flow at a routine first‐trimester scan at 11 weeks of gestation. No structural abnormalities were detected by the ultrasound scan. Karyotyping by chorionic villus sampling led to the diagnosis of mosaic trisomy 8, which was confirmed by fluorescent in‐situ hybridization on fetal tissue samples. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
Fetal nuchal translucency and normal chromosomes: a long‐term follow‐up study
Authors: Hiippala A. , Eronen M. , Taipale P. , Salonen R. , Hiilesmaa V.
Published: March 2003

Objective

To assess the impact of increased nuchal translucency observed during early pregnancy on the subsequent health of children with normal chromosomes, with special attention to cardiac anatomy and function.

Methods

Clinical examination and detailed cardiac evaluation were carried out in 50 chromosomally normal children at the age of 2.4–7.1 years who had had a nuchal translucency measurement of ≥ 3 mm at 13–15 weeks' gestation. The data of two babies who died of heart defects were also included.

Results

Major cardiac defects were identified in four (8%) of the children. The growth of all children was within normal limits. One child had Noonan syndrome, one had a cleidocranial dysplasia and a third had a developmental delay together with an unrecognized syndrome. Webs in the neck region were noticed in two children, with no associated pathology.

Conclusions

In chromosomally normal fetuses with increased nuchal translucency, fetal echocardiography is necessary to identify major cardiac defects. In general, the parents can be reassured that, in the great majority, postnatal development is normal. Copyright © 2001 International Society of Ultrasound in Obstetrics and Gynecology
Ultrasound evaluation of the fetal skull base throughout pregnancy
Authors: Degani S. , Leibovitz Z. , Shapiro I. , Gonen R. , Ohel G.
Published: March 2003

Objective

To construct nomograms for cranial base parameters of normal fetuses.

Study design

A cross‐sectional study of 386 normal singleton fetuses at 14–40 weeks' gestation. Measurements of the length and width of the sphenoid bone anteriorly and the otic cartilage posteriorly and of the angles between the ridges were obtained.

Results

Nomograms of the length and width of sphenoid ridge and otic cartilage, and of the angles in the cranial fossae are presented. A linear growth function was observed between cranial base measurements (sphenoid ridge length, otic cartilage length, cranial base angles) and gestational age, femur length and biparietal diameter.

Conclusion

Measurements of the length of cranial base ridges and the angles between them can be obtained easily in the second and third trimesters and might prove useful in the evaluation of pregnancies at high risk for associated fetal abnormalities. Copyright © 2002 ISUOG
Comparison of three‐dimensional, two‐dimensional and color Doppler ultrasound in predicting the presence of a nuchal cord at birth
Authors: Hanaoka U. , Yanagihara T. , Tanaka H. , Hata T.
Published: March 2003

Objectives

To compare the use of two‐dimensional, color Doppler and three‐dimensional ultrasound for predicting the presence of a nuchal cord at birth.

Methods

Eighty‐five singleton pregnancies without nuchal cord and 35 with nuchal cord (30 with a single coil of cord, four with a double coil, and one in which the cord was coiled around the neck three times) were studied within 1 week before delivery using transabdominal three‐dimensional sonography. Two‐dimensional and color Doppler ultrasound were also conducted for comparison.

Results

Two‐dimensional, color Doppler and three‐dimensional sonography identified in utero 24 (69%), 29 (83%) and 25 (71%), respectively, of the cases of nuchal cord found at birth. There were no significant differences in overall diagnostic indices of each diagnostic modality for detecting nuchal cord. However, the ability to view the nuchal cord (subjective assessment of the ease of visualization of nuchal cord) was better with three‐dimensional sonography than with two‐dimensional or color Doppler ultrasound.

Conclusions

Three‐dimensional surface imaging does not provide more useful diagnostic information compared with two‐dimensional and color Doppler ultrasound for detecting nuchal cord in utero. Copyright © 2002 ISUOG
Reference values for ductus venosus Doppler flow measurements at 10–14 weeks of gestation
Authors: Prefumo F. , Risso D. , Venturini P. L. , De Biasio P.
Published: March 2003

Objectives

To calculate reference ranges for ductus venosus Doppler measurements obtained transabdominally at 10–14 weeks of gestation.

Design

Two hundred and one normal fetuses with a crown–rump length (CRL) ranging from 38 to 88 mm were examined in a cross‐sectional study. The pulsatility index for veins (PIV), peak velocity during ventricular systole (S‐wave), lowest forward velocity during atrial contraction (A‐wave) and time‐averaged maximum velocity (TAMXV) were recorded from the ductus venosus. Flow velocity waveforms were also classified as normal or abnormal according to the presence (normal) or absence or reversal (abnormal) of frequencies during atrial contraction.

Results

Three of 201 fetuses showed an abnormal flow pattern (1.5%; 95% exact confidence interval, 0.3–4.3%). In the 198 fetuses with a normal flow pattern, the mean PIV ranged from 1.07 at a CRL of 38 mm to 1.00 at a CRL of 88 mm (r = −0.093; P = 0.19). A significant increase in mean blood flow velocity with increasing CRL was noted for the S‐wave (27.0 cm/s to 33.6 cm/s; r = 0.17; P = 0.02), the A‐wave (5.9 cm/s to 7.8 cm/s; r = 0.14; P = 0.04) and the TAMXV (19.4 cm/s to 25.3 cm/s; r = 0.19; P < 0.01). Crown–rump length‐specific reference ranges for each parameter were calculated using the method of scaled absolute residuals.

Conclusions

Abnormal ductus venosus flow patterns could be observed in normal fetuses, even if they ocurred with a low prevalence. Reference values for Doppler measurements were established in fetuses with normal patterns of flow. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Prenatal diagnosis of ventriculocoronary arterial fistula in a fetus with hypoplastic left heart syndrome and aortic atresia
Authors: Chaoui R. , Tennstedt C. , Göldner B.
Published: March 2003

In a fetus with a hypoplastic left heart syndrome detected at 26 weeks' gestation, a communication between the left ventricular cavity and the left coronary artery was detected using color Doppler. Bidirectional flow was demonstrated and the ventricle was shown to be filled via the fistula during diastole. After premature birth at 31 weeks and neonatal death, autopsy confirmed the findings. Because the association of a heart defect with ventriculocoronary communications worsens the neonatal prognosis, it should be ruled out in fetuses with hypoplastic left heart syndrome before parents are counseled. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Hereditary subependymal heterotopia associated with mega cisterna magna: antenatal diagnosis with magnetic resonance imaging
Authors: Bargalló N. , Puerto B. , De Juan C. , Martinez‐Crespo J. M. , Lourdes Olondo M.
Published: March 2003

Bilateral nodular subependymal heterotopia has recently been identified as a hereditary disease linked to the X‐chromosome. The sonographic findings are very subtle and difficult to observe during the second trimester when the germinal matrix is at its largest. Fetal magnetic resonance imaging facilitates visualization of the periventricular area. We report a case of bilateral nodular heterotopia associated with mega cisterna magna diagnosed by ultrasound and magnetic resonance imaging at 29 weeks' gestation. Magnetic resonance imaging of the brain of the mother revealed similar findings to those observed in the fetus and neonate. This case confirms the association between mega cisterna magna and bilateral periventricular nodular heterotopia and demonstrates that neuroimaging studies of the mother can contribute to the fetal diagnosis. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Intra‐ and interobserver reproducibility of ultrasound measurements of cervical length and width in the second and third trimesters of pregnancy
Authors: Valentin L. , Bergelin I.
Published: March 2003

Objectives

To determine intra‐ and interobserver reproducibility of ultrasound measurements of cervical length and width in the second and third trimesters of pregnancy.

Design

Twenty healthy women in the second or third trimester of pregnancy underwent transvaginal ultrasound examination of the cervix by two examiners. Three replicate meaurements of cervical length and width were taken by each observer for each woman. Intraobserver repeatability was expressed as the difference between the highest and lowest measurement value obtained by one observer, and as the repeatability coefficient and intraclass correlation coefficient. Interobserver reproducibility was expressed as the difference between the mean of the three measurements of each observer, limits of agreement, and interclass correlation coefficient. The repeatability coefficient/limits of agreement define the range within which 95% of the differences between two measurements by the same observer/two observers are likely to fall.

Results

Intra‐ and interobserver differences did not vary in any systematic way over the range of values measured. For cervical length measurements the repeatability coefficient was ± 5.4 mm for Observer 1 and ± 5.9 mm for Observer 2. The intraclass correlation coefficient for cervical length measurements was 0.93 for both observers. The corresponding coefficients for cervical width measurements were ± 3.9 mm and ± 7.3 mm, and 0.97 and 0.91. The interclass correlation coefficient for cervical length measurements was 0.76, the mean interobserver difference was 0.4 mm, and the limits of agreement were −10.0 mm to 10.8 mm. For cervical width measurements the interclass correlation coefficient was 0.74, the mean interobserver difference was −0.02 mm, and the limits of agreement were −12.4 mm to 12.4 mm. There was no systematic difference between the first, second and third cervical length measurements and no systematic bias between the two observers, and the results were not affected by which of the two examiners started the examination (three‐way analysis of variance). The same was true of cervical width measurements.

Conclusions

Our results do not support the contention that the first measurement of cervical length is the longest. There is substantial intra‐ and interobserver variability in the results of measurements of cervical length and width, even when experienced observers perform the measurements under standardized conditions. It is important to consider the possibility of ‘measurement error’ when ultrasound measurements of cervical length and width are used in clinical practice to monitor women at high risk of delivering preterm or to screen for preterm birth. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Split hand and foot malformation: ultrasound detection in the first trimester
Authors: Lapaire O. , Schiesser M. , Peukert R. , Holzgreve W. , Tercanli S.
Published: March 2003

The split hand split foot malformation is a rare disorder inherited in an autosomal dominant pattern with variable expression. In our case it was detected early by ultrasound in the twelfth week of gestation. To our knowledge, this is the earliest finding by ultrasound of this malformation. The sonographic findings were bilateral split hands and split foot. No other associated malformation was observed. The pathological findings were consistent with the diagnosis of split hand split foot malformation. Prenatal diagnosis, the genetic background, and the differential diagnosis are discussed. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Spermiogenesis and spermiation in a marsupial, the tammar wallaby (Macropus eugenii)
Authors: LIN MINJIE , HARMAN AMANDA , RODGER JOHN C.
Published: March 2003

Fourteen steps of spermatid development in the tammar wallaby (Macropus eugenii), from the newly formed spermatid to the release of the spermatozoon into the lumen of the seminiferous tubules, were recognised at the ultrastructural level using transmission and scanning electron microscopy. This study confirmed that although the main events are generally similar, the process of the differentiation of the spermatid in marsupials is notably different and relatively more complex than that in most studied eutherian mammals and birds. For example, the sperm head rotated twice in the late stage of spermiogenesis: the shape of the spermatid changed from a T‐shape at step 10 into a streamlined shape in step 14, and then back to T‐shape in the testicular spermatozoa. Some unique figures occurring during the spermiogenesis in other marsupial species, such as the presence of Sertoli cell spurs, the nuclear ring and the subacrosomal space, were also found in the tammar wallaby. However, an important new finding of this study was the development of the postacrosome complex (PAC), a special structure that was first evident as a line of electron dense material on the nuclear membrane of the step 7 spermatid. Subsequently it became a discontinuous line of electron particles, and migrated from the ventral side of the nucleus to the area just behind the posterior end of the acrosome, which was closely located to the sperm–egg fusion site proposed for Monodelphis domestica (Taggart et al. 1993). The PAC and its possible role in both American and Australian marsupials requires detailed examination. Distinct immature features were discovered in the wallaby testicular spermatozoa. A scoop shape of the acrosome was found on the testicular spermatozoa of the tammar wallaby, which was completely different to the compact button shape of acrosome in ejaculated spermatozoa. The fibre network found beneath the cytoplasm membrane of the midpiece of the ejaculated sperm also did not occur in the testicular spermatozoa, although the structure of the principal piece was fully formed and had no obvious morphological difference from that of the epididymal and ejaculated spermatozoa. The time frame of the formation of morphologically mature spermatozoa in the epididymis of the tammar wallaby needs to be determined by further studies.
Analysis of fused maxillary incisor dentition in p53‐deficient exencephalic mice
Authors: KAUFMAN M. H. , KAUFMAN D. B. , BRUNE R. M. , STARK M. , ARMSTRONG J. F. , CLARKE A. R.
Published: March 2003

Out of a total of 21 exencephalic p53‐deficient embryonic and newborn mice, 6 (28.6%) possessed fused maxillary incisor teeth. On histological analysis of the 5 examples seen on day 19.5 of gestation and newborn mice, 3 varieties were observed: an example of ‘simple’ fusion, 3 examples of simple fusion each of which contained a ‘dens in dente’ (‘tooth within a tooth’), and a single example in which the fused teeth were associated with a median supernumerary incisor tooth which, while deeply indenting the labial surface of the fused teeth, was in all locations a completely separate unit. 3‐D reconstructions of the fused teeth demonstrated that they were all of the fusio subtotalis variety. No gross abnormalities were observed in the other dentition in these mice. It is noted that in mice fused maxillary incisor teeth are relatively commonly associated with both hypervitaminosis A‐induced and trypan blue‐induced exencephaly. It is believed that the presence of dens in dente within fused maxillary incisor teeth has only once been reported in mice, and the association between fused maxillary incisor teeth and a median supernumerary incisor tooth has not previously been reported in this species.
Role of glutamate in the regulation of the outgrowth and motility of neurites from mouse spinal cord neurons in culture
Authors: OWEN ALUN D. , BIRD MARGARET M.
Published: March 2003

The excitatory amino acid glutamate has been shown to be toxic to a number of neuronal cell types both in vitro and in vivo. It has also been shown to be capable of controlling the development of neurons grown in vitro. Using time‐lapse video microscopy techniques the effects of glutamate on the rate of neurite outgrowth and growth cone motility were examined on cultured mouse spinal cord neurons. Concentrations in the range of 1 to 100 µM caused a significant inhibition of neurite outgrowth and concentrations of 10 and 100 µM significantly inhibited growth cone activity. In addition it was shown that the kainate/AMPA receptor antagonist (±)3‐(2‐carbvoxypiperazin‐4‐yl)‐propyl‐l‐phosphonic acid, but not the NMDA receptor antagonist 6,7‐dinitroquinoxaline‐2,3‐dione, was capable of blocking the inhibitory actions of glutamate on both outgrowth and motility. These results show that, at least in the culture system employed, glutamate might have a role in regulating neuronal development and function.
Distribution of myocardial macrophages in the normal human heart
Authors: AZZAWI MAY , HASLETON PHILIP S. , KAN SAU WAN , HILLIER VALERIE F. , QUIGLEY ALICIA , HUTCHINSON IAN V.
Published: March 2003

Macrophages are important in inflammatory processes in heart disease and in transplantation rejection. A resurgence of interest in the macrophage has emanated from recent evidence implicating it as an effector cell in atherosclerosis and transplantation rejection. The detailed distribution of the macrophage within the normal human heart is unknown. We quantified macrophage numbers in the different chambers of the heart. Large tissue blocks (1.5–2.0 cm3) were removed from specific sites in 5 ‘normal’ control hearts (2 males, 3 females, age range 19–46 y). Paraffin‐embedded sections were stained with a CD68 pan macrophage marker. Positive cells were enumerated within 20 random fields. Results were analysed using a generalised linear modelling method using the Poisson distribution. Macrophages were identified within septa, and often close to blood vessels, in the myocardium, and in the majority of areas in all hearts. Macrophage numbers varied significantly between areas (range 0–6 cells/high power field; P<0.001), and between the 5 hearts analysed (P<0.001). In general, there were significantly more macrophages in the ventricles (RV P<0.01, LV P<0.05), but these differences were affected by heart differences. This study provides a baseline for the range of macrophage numbers within normal hearts, thus enabling comparisons with macrophage numbers within diseased and transplanted hearts.
Innervation of intestinal arteries by axons with immunoreactivity for the vesicular acetylcholine transporter (VAChT)
Authors: LI Z. S. , FOX‐THRELKELD J. E. T. , FURNESS J. B.
Published: March 2003

The presence of a cholinergic innervation of arterioles within the gut wall is suggested by pharmacological studies of nerve mediated vasodilatation, but attempts to identify nerve cells that give rise to cholinergic vasodilator fibres have yielded discrepant results. In the present work, antibodies to the vesicular acetylcholine transporter protein (VAChT) were used to investigate the relationships of immunoreactive nerve fibres to submucosal arterioles. Comparison was made with cerebral arteries, which are known to be cholinergically innervated. Double labelling immunohistochemical techniques revealed separate VAChT and tyrosine hydroxylase (TH) immunoreactive (IR) fibres innervating all sizes of arteries of the submucosa of the stomach, ileum, proximal colon, distal colon and rectum as well as the cerebral arteries. Arterioles of all digestive tract regions had greater densities of TH‐IR innervation than VAChT‐IR innervation. In the ileum, double labelling for VAChT‐IR and VIP‐IR or calretinin‐IR showed more VAChT‐IR than either VIP‐IR or calretinin‐IR fibres. Calretinin‐IR and VAChT‐IR were colocalised in a majority of calretinin‐IR axons, but VIP‐IR and VAChT‐IR were not colocalised. All calretinin‐IR nerve cells in submucous ganglia were immunoreactive for choline acetyltransferase, but only 1–2% of VIP‐IR nerve cells were immunoreactive. Extrinsic denervation of the ileum did not alter the distribution of VAChT‐IR fibres, but it eliminated TH‐IR fibres. Removal of myenteric ganglia (myectomy) did not alter the distribution of fibres with VAChT or TH‐IR. This work thus provides evidence for cholinergic innervation of intrinsic arterioles throughout the digestive tract and indicates that the fibres in the small intestine originate from submucosal nerve cells.
Squatting facets on the neck of the talus and extensions of the trochlear surface of the talus in late Byzantine males
Authors: OYGUCU I. H. , KURT M. A. , IKIZ I. , EREM T. , DAVIES D. C.
Published: March 2003

Remodelling of bone occurs in response to physical stress. Habitual squatting is associated with modifications of the neck of the talus (squatting facets) and its trochlear/malleolar surfaces (trochlear extensions), and individual populations exhibit different incidences of these modifications that reflect their lifestyle. The occurrence of talar modifications was therefore investigated in a population of late Byzantine (13th century AD) adult male skeletons. Lateral squatting facets occurred most frequently (37.7%), but medial (0.6%), combined (0.6%) and continuous (gutter‐like) facets (0.6%) were also observed. Lateral (8.0%), medial (10.9%) and continuous (lateral/central/medial) extensions (4.6%) of the trochlear surface were all present in the late Byzantine population. There was no evidence of side dimorphism. The occurrence of lateral squatting facets in the late Byzantine population was greater than that reported for modern Europeans, but similar to that reported for some populations of modern Indians. The frequency of occurrence of trochlear extensions in the late Byzantine population was substantially less than in modern Indian populations, but similar to modern Europeans. Therefore, it is unlikely that precisely the same factors determine the expression of squatting facets and trochlear extensions.
On the ultrastructure of softened cartilage: a possible model for structural transformation
Authors: CHEN MIN‐HUEY , BROOM NEIL
Published: March 2003

The fibrillar architecture in the general matrix of softened cartilage has been compared with that of the normal matrix using both Nomarski light microscopy and transmission electron microscopy with combined stereoscopic reconstruction. A pseudorandom network developed from an overall radial arrangement of collagen fibrils is the most fundamental ultrastructural characteristic of the normal general matrix. This, in turn, provides an efficient entrapment system for the swelling proteoglycans. Conversely, the most distinctive feature of the softened matrix is the presence of parallel and relatively unentwined fibrils, strongly aligned in the radial direction. The presence of an optically resolvable fibrous texture in the softened cartilage matrix indicates the presence of discrete bundles of closely packed and aligned fibrils at the ultrastructural level of organisation. The general absence of such texture in the normal cartilage general matrix is consistent with the much greater degree of interconnectedness and related short‐range obliquity in the fibrillar architecture, hence the importance of the term pseudorandom network. A mechanism of structural transformation is proposed based on the important property of lateral interconnectivity in the fibrils which involves both entwinement and nonentwinement based interactions. The previously reported difference in intrinsic mechanical strength between the normal and softened matrices is consistent with the transformation model proposed in this study.
Epithelial‐connective tissue boundary in the oral part of the human soft palate
Authors: PAULSEN FRIEDRICH , THALE ANDREAS
Published: March 2003

The papillary layer of the oral part of the human soft palate was studied in 31 subjects of different age by means of histological, immunohistochemical and scanning electron microscopical methods. For scanning electron microscopy a new maceration method was introduced. Results determine epithelial thickness, height and density of connective tissue papillae and their 3‐dimensional architecture inside the lining epithelium as well as the collagenous arrangement of the openings of the glandular ducts. The individual connective tissue papillae of the soft palate are compared with the connective tissue boundary on the other side of the oral cavity. The connective tissue plateaux carrying a variable number of connective tissue papillae were found to be the basic structural units of the papillary body. The function of the epithelial‐connective tissue interface and the extracellular matrix arrangement in the lamina propria are discussed in order to promote the comparability of normal with pathologically altered human soft palates.
Alterations in rat vaginal histology by exogenous gonadotrophins
Authors: DALY T. JOSEPH M. , KRAMER BEVERLEY
Published: March 2003

Changes in vaginal epithelium are known to occur during the normal oestrous or menstrual cycle and in ovariectomised animals in response to various hormones. However, vaginal changes due to exogenous gonadotrophins superimposed on the normal hormonal milieu as occurs in in vitro fertilisation programmes have not previously been demonstrated. Female rats were hyperstimulated with follicle stimulating hormone and human chorionic gonadotrophin prior to mating. Control mated animals were not injected. Vaginal tissue was collected at 4.5, 5.5 and 6.5 d after mating. Tissue was processed for light microscopy. Hyperstimulation by the exogenous gonadotrophins caused mucification, a decrease in the number of epithelial layers and an increase in the thickness of the epithelium on d 4.5 of pregnancy. The mitotic index of the epithelial cells was depressed in the hyperstimulated rats with respect to control animals. Exposure to high levels of oestradiol and an altered progesteroneoestradiol ratio appear to have caused the changes in the vaginal epithelium.
Factors involved in the ‘rotation’ of the human embryonic stomach around its longitudinal axis: computer‐assisted morphometric analysis
Authors: NEBOT‐CEGARRA JOSEP , MARACULLA‐SANZ ENRIC , REINA‐DE LA TORRE FRANCISCO
Published: March 2003

The majority of studies as to whether gastric and nongastric factors are involved in the ‘rotation’ of the human embryonic stomach around its longitudinal axis have been morphological. The aim of this study was to analyse, with morphometric support, the influence on the angular modifications during gastric rotation of the simultaneous changes of the gastric walls and mesenteric growth, and the volumes of organs adjacent to the stomach (right, left and posterior groups). Computer imaging techniques were applied on cross sections of a graded series of 10 human embryos (from Carnegie stage (CS) 11) and 2 fetuses. A clockwise gastric rotation occurred during the embryonic period. The most rapid angular modifications took place from CS 11 to 16, after the rotation became oscillatory with angular changes in clockwise and anticlockwise directions, reaching the highest value at CS 18 (at the supraomental part of the stomach: 54.37°; at the omental part: 68.03°); after this period the angular values tended to stabilise. The predominant growth of the left gastric wall over the right and the changes in the width of the gastric mesentery were the most persistent factors involved in the modifications of the transverse gastric angle during the embryonic period although without relationship to their direction. During the increasing angular phases, clockwise rotation was promoted by the decrease of the volume of any group of organs adjacent to the stomach. When the volume of the left and posterior groups increased simultaneously, clockwise or anticlockwise angular directional change was related to the respective decrease or increase adjacent organ volume to the right. We conclude that the stomach of the human embryo undergoes heterogeneous and multifactorial rotation as a consequence of the overall increase in gastric wall growth to the left and the increase of gastric mobility produced by the previous mesenteric enlargement, and that the rotational direction results from the forces exerted on the stomach and the gastric mesenteries by the adjacent organs.
Acrosome formation during sperm transit through the epididymis in two marsupials, the tammar wallaby (Macropus eugenii) and the brushtail possum (Trichosurus vulpecula)
Authors: LIN MINJIE , RODGER JOHN C.
Published: March 2003

In certain Australian marsupials including the tammar wallaby (Macropus eugenii) and the brushtail possum (Trichosurus vulpecula), formation of the acrosome is not completed in the testis but during a complex differentiation process as spermatozoa pass through the epididymis. Using transmission and scanning electron microscopy this paper defined the process of acrosome formation in the epididymis, providing temporal and spatial information on the striking reorganisation of the acrosomal membranes and matrix and of the overlying sperm surface involved. On leaving the testis wallaby and possum spermatozoa had elongated ‘scoop’‐shaped acrosomes projecting from the dorsal surface of the head. During passage down the epididymis, this structure condensed into the compact button‐like organelle found on ejaculated spermatozoa. This condensation was achieved by a complex process of infolding and fusion of the lateral projections of the ‘scoop’. In the head of the epididymis the rims of the lateral scoop projections became shorter and thickened and folded inwards, to eventually meet midway along the longitudinal axis of the acrosome. As spermatozoa passed through the body of the epididymis the lateral projections fused together. Evidence of this fusion of the immature outer acrosomal membrane is the presence of vesicles within the acrosomal matrix which persist even in ejaculated spermatozoa. When spermatozoa have reached the tail of the epididymis the acrosome condenses into its mature form, as a small button‐like structure contained within the depression on the anterior end of the nucleus. During the infolding process, the membranes associated with the immature acrosome are either engulfed into the acrosomal matrix (outer acrosomal membrane), or eliminated from the sperm head as tubular membrane elements (cytoplasmic membrane). Thus the surface and organelles of the testicular sperm head are transient structures in those marsupials with posttesticular acrosome formation and this must be taken into consideration in attempts to dissect the cell and molecular biology of fertilisation.
Histochemical and immunohistochemical analysis of the mechanism of calcification of Meckel's cartilage during mandible development in rodents
Authors: ISHIZEKI K. , SAITO H. , SHINAGAWA T. , FUJIWARA N. , NAWA T.
Published: March 2003

It is widely accepted that Meckel's cartilage in mammals is uncalcified hyaline cartilage that is resorbed and is not involved in bone formation of the mandible. We examined the spatial and temporal characteristics of matrix calcification in Meckel's cartilage, using histochemical and immunocytochemical methods, electron microscopy and an electron probe microanalyser. The intramandibular portion of Meckel's cartilage could be divided schematically into anterior and posterior portions with respect to the site of initiation of ossification beneath the mental foramen. Calcification of the matrix occurred in areas in which alkaline phosphatase activity could be detected by light and electron microscopy and by immunohistochemical staining. The expression of type X collagen was restricted to the hypertrophic cells of intramandibular Meckel's cartilage, and staining with alizarin red and von Kossa stain revealed that calcification progressed in both posterior and anterior directions from the primary centre of ossification. After the active cellular resorption of calcified cartilage matrix, new osseous islands were formed by trabecular bone that intruded from the perichondrial bone collar. Evidence of such formation of bone was supported by results of double immunofluorescence staining specific for type I and type II collagens, in addition to results of immunostaining for osteopontin. Calcification of the posterior portion resembled that in the anterior portion of intramandibular Meckel's cartilage, and our findings indicate that the posterior portion also contributes to the bone formation of the mandible by an endochondral‐type mechanism of calcification.
Quantitative description of the spatial arrangement of organelles in a polarised secretory epithelial cell: the salivary gland acinar cell
Authors: MAYHEW TERRY M.
Published: March 2003

Previous quantitative descriptions of cellular ultrastructure have focused on spatial content (volume, surface area and number of organelles and membrane domains). It is possible to complement such descriptions by also quantifying spatial arrangements. Hitherto, applications of stereological methods for achieving this (notably, estimation of covariance and pair correlation functions) have been confined to organ and tissue levels. This study explores 3‐dimensional subcellular arrangements of key organelles within acinar cells of rabbit parotid salivary glands, highly polarised epithelial cells specialised for exocrine secretion of α‐amylase. It focuses on spatial arrangements of secretion product stores (zymogen granules), rough endoplasmic reticulum (RER) and mitochondria. Systematic random samples of electron microscopical fields of view from 3 rabbits were analysed using test grids bearing linear dipole probes of different sizes. Unbiased estimates of organelle volume densities were obtained by point counting and estimates of covariance and pair correlation functions by dipole counting. Plots of pair correlation functions against dipole length identified spatial arrangement differences between organelle types. Volumes within RER and mitochondrial compartments were positively correlated with themselves at distances below 4 μm and 2 μm respectively but were essentially randomly arranged at longer distances. In sharp contrast, zymogen granules were not randomly arranged. They were clustered at distances below 6–7 μm and more widely scattered at greater distances. These findings provide quantitative confirmation of the polarised arrangement of zymogen granules within acinar cells and further support for the relative invariance of biological organisation between subjects.
Bilateral superficial median arteries
Authors: NAKATANI TOSHIO , IZUMI ATSUSHI , TANAKA SHIGENORI
Published: March 2003

A superficial artery may be present in the forearm, arising from the axillary, brachial or superficial brachial arteries and crossing over the origin of the flexor muscles of the forearm to reach the palm (Adachi, 1928; Bergman et al. 1988). When this superficial artery continues as the normal ulnar artery accompanying the ulnar nerve at the wrist, it is referred to as the superficial ulnar artery, with an incidence of ∼4%. When the artery passes below or superficial to the flexor retinaculum in the middle of the forearm, sometimes continuing to join the superficial palmar arch, it is called the superficial median artery, with an incidence of ∼1%. We have observed a relatively rare variation involving the presence of a superficial median artery in both upper limbs. We discuss the clinical importance and the developmental aspects of this arterial variation.
Inhibition of dendrite formation in mouse melanocytes transiently transfected with antisense DNA to myosin Va
Authors: EDGAR ALASDAIR J. , BENNETT JONATHAN P.
Published: March 2003

In mice a molecular motor of the myosin V class (designated myosin Va) is known to be the product of the dilute locus, where a mutation prevents melanosome transport in melanocytes. There is conflicting evidence about whether it has a role in dendrite outgrowth. We investigated its role by transiently transfecting antisense oligonucleotides to inhibit its expression in a melanocyte cell line. We demonstrated mRNA and protein expression of myosin Va in 3 mouse melanocyte lines and 1 human melanoma cell line, using RT‐PCR and immunoblotting. Two splice variants were found in human cells whilst only the longer transcript, containing an additional exon, was present in mouse melanocyte lines. The shorter variant was detected in other mouse tissues. Myosin Va protein levels were similar in 3 melanocyte lines with differing amounts of pigmentation, indicating that expression of myosin Va is not tightly coupled to expression of melanin. Immunocytochemistry showed 2 types of myosin Va localisation. A punctate pattern of staining concentrated in the perinuclear region was indicative of organelle association, and the observation of occasional linear punctate staining aligned with F‐actin bundles supported the idea that myosin Va has a role in transporting melanosomes along actin filaments. Staining was also intense at tips of dendrites and at sites of dendrite‐cell contact, consistent with a possible role in dendrite growth. Transient transfection of antisense phosphorothioate oligodeoxynucleotides targeted against myosin Va mRNA reduced expression of myosin Va protein in cultured mouse melan‐a melanocytes by over 70% 20 h after transfection whereas a control (shuffled sequence) oligonucleotide did not. Upon trypsinisation and replating these cells the capacity of the transfected cells to extend new dendrites was reduced in the cells containing the specific antisense oligonucleotides but unaffected by the control oligonucleotide. Image analysis confirmed that the effect of transfection on morphology was statistically significant (P<0.01). In contrast when cells were not trypsinised and replated following transfection so that previously existing dendrites could persist, the normal dendritic morphology continued to be observed. We conclude that in addition to its involvement in melanosome transport, myosin Va has a role in the extension of new dendrites by melanocytes but not in maintenance of pre‐existing dendrites.
A densitometric analysis of the human first metatarsal bone
Authors: MUEHLEMAN CAROL , BAREITHER DANIEL , MANION BRUCE L.
Published: March 2003

Bone responds to the stresses placed on it by remodeling its structure, which includes shape, trabecular distribution and density distribution. We studied 49 pairs of cadaveric human 1st metatarsal bones in an attempt to establish the pattern of density distribution and to correlate it with the biomechanical function of the bone. We found that the head is denser than the base, the dorsal portion of the whole metatarsal is denser than the plantar portion and the lateral portion of the whole metatarsal is denser than the medial aspect. The same pattern of density with respect to dorsal vs plantar and lateral vs medial was also seen in the head when it was examined alone. When we compared the 4 portions of the head with the same portion of the metatarsal as a whole we found that only the medial portion of the head was less dense than its respective portion of the whole metatarsal. All of these patterns of density distribution are consistent with respect to age, sex and laterality. We have also hypothesised as to the relationship between density distribution seen both in the whole metatarsal and in the metatarsal head and their biomechanical function in the gait cycle.
In situ hybridisation study of type I, II, X collagens and aggrecan mRNAs in the developing condylar cartilage of fetal mouse mandible
Authors: FUKADA KENJI , SHIBATA SHUNICHI , SUZUKI SHOICHI , OHYA KEIICHI , KURODA TAKAYUKI
Published: March 2003

The aim of this study was to investigate the developmental characteristics of the mandibular condyle in sequential phases at the gene level using in situ hybridisation. At d 14.5 of gestation, although no expression of type II collagen mRNA was observed, aggrecan mRNA was detected with type I collagen mRNA in the posterior region of the mesenchymal cell aggregation continuous with the ossifying mandibular bone anlage prior to chondrogenesis. At d 15.0 of gestation, the first cartilaginous tissue appeared at the posterior edge of the ossifying mandibular bone anlage. The primarily formed chondrocytes in the cartilage matrix had already shown the appearance of hypertrophy and expressed types I, II and X collagens and aggrecan mRNAs simultaneously. At d 16.0 of gestation, the condylar cartilage increased in size due to accumulation of hypertrophic chondrocytes characterised by the expression of type X collagen mRNA, whereas the expression of type I collagen mRNA had been reduced in the hypertrophic chondrocytes and was confined to the periosteal osteogenic cells surrounding the cartilaginous tissue. At d 18.0 of gestation before birth, cartilage‐characteristic gene expression had been reduced in the chondrocytes of the lower half of the hypertrophic cell layer. The present findings demonstrate that the initial chondrogenesis for the mandibular condyle starts continuous with the posterior edge of the mandibular periosteum and that chondroprogenitor cells for the condylar cartilage rapidly differentiate into hypertrophic chondrocytes. Further, it is indicated that sequential rapid changes and reductions of each mRNA might be closely related to the construction of the temporal mandibular ramus in the fetal stage.
Sequential changes in trace metal, metallothionein and calmodulin concentrations in healing skin wounds
Authors: LANSDOWN A. B. G. , SAMPSON B. , ROWE A.
Published: March 2003

Metalloenzymes have an important role in repair and regenerative processes in skin wounds. Demands for different enzymes vary according to the phase in the healing cascade and constituent events. Sequential changes in the concentrations of calcium, copper, magnesium and zinc were studied in the incisional wound model in the rat over a 10 d period. Copper levels remained low (<10 μg/g dry weight) throughout, but calcium, magnesium and zinc increased from wounding and peaked at about 5 d at a time of high inflammation, granulation tissue formation and epidermal cell proliferation. Metal concentrations declined to normal by 7 d when inflammation had regressed, re‐epithelialisation of the wound site was complete and the ‘normalisation’ phase had commenced. Although the wound was overtly healed by 10 d, the epidermis was still moderately hyperplastic. In view of competitive binding of trace metals at membrane receptors and carrier proteins, the ratios or balance between these trace metals was examined and the significance is discussed. Using immunocytochemistry, we demonstrated increases in metallothionein immunoreactivity as an indication of zinc and copper activity in the papillary dermis and in basal epidermal cells near the wound margin 1–5 d after wounding. This is consistent with metalloenzyme requirements in inflammation and fibrogenesis. Calmodulin, a major cytosolic calcium binding protein was highest in maturing keratinocytes and in sebaceous gland cells of normal skin; it was notably more abundant in the epidermis near the wound margin and in re‐epithelialising areas at a time when local calcium levels were highest.