bluuebunny/crossref_metadata_2025 huggingface dataset:
The Significance of non‐visualization of the fetal gallbladder in early pregnancy
Authors: Blazer S. , Zimmer E. Z. , Bronshtein M.
Published: March 2003

Purpose:  To assess the incidence of a non‐visualized gallbladder in early pregnancy and to determine its prognostic significance.

Material and methods:  Transvaginal ultrasound examination was performed in 29 749 consecutive pregnant women at 14–16 weeks gestation. All women underwent a detailed fetal survey prospectively. The incidence and associated risk in cases of a non‐visualized fetal gallbladder was determined.

Results:  The gallbladder was not visualized in early pregnancy in 34 fetuses, giving an incidence of 0.11% (1 in 875 pregnancies). Associated malformations were detected in 14 fetuses (41%), and in 20 fetuses non‐visualization of the gallbladder was an isolated finding. All fetuses with an isolated finding had a normal outcome, in 13 fetuses the gallbladder was detected later on in pregnancy, in five no gallbladder was found after delivery, and two patients were lost in follow up. Of the 14 fetuses with associated anomalies, five had also an abnormal karyotype. Termination of pregnancy was performed in nine of these fetuses. Of the cases which continued pregnancy there was one case of neonatal death, two cases of developmental delay and only one normal child.

Conclusion:  Non‐visualization of the fetal gallbladder in the early pregnancy is uncommon but is associated with a high incidence of associated anomalies. Fetuses with an isolated finding of a non‐visualized gallbladder have usually a favorable outcome.
Ultrasonographic findings of VATER association
Authors: Tanemura M. , Tsukishiro S. , Suzumori K.
Published: March 2003

Purpose:  VATER association is a combination of congenital anomalies including vertebral defects (V), anal atresia (A), tracheoesophageal fistula (TE), esophageal atresia (E), and radial and renal anomalies (R). This report describes the prenatal progress of four such cases and the features of ultrasonographic findings.

Methods:  Case (1): the mother was referred at 12 weeks gestation because of a fetal abdominal cyst. Bilateral hydronephroses and an expansive bladder were detected by ultrasonography. At 36 weeks polyhydramnios appeared, and soon she delivered. V, A, TE, E and R were confirmed. Case (2): the mother was referred at 14 weeks because of a fetal abdominal cyst and oligohydramnios. Ultrasonography suggested megalocystis based on urethral atresia. An infant was delivered at 27 weeks and died right thereafter. Autopsy confirmed V, A, R, tracheal atresia, genital anomaly and megalocystis. Case (3): the mother was transported at 37 weeks because of fetal distress. Polyhydamnios had been suspected on a routine office visit. The infant was delivered by cesarean section. TE, E and limb defects were detected. Case (4): the mother was referred at 26 weeks because of anhydramnios and mediastinal shift. Ultrasonography and fetal MRI indicated renal agenesis and congenital diaphragmatic hernia. Autopsy on a stillborn infant revealed V, A, TE, E, R and diaphragmatic hernia.

Results and conclusions:  The features of ultrasonographic findings of VATER association were abnormality of urinary organs and amniotic fluid volume. However, in the cases with esophageal atresia, estimation of renal function was difficult.
Ultrasonographic normograms of the fetal chin and filtrum during pregnancy
Authors: Jaffa A. J. , Wolman I. , Har‐Toov J. , Fait G. , Amster R. , Lessing J. B. , Gull I. , Jaffa A. J.
Published: March 2003

Introduction:  Abnormal sizes of the chin and of the filtrum or their proportions are morphological features in certain syndromes. Both chin and filtrum can be visualized and measured from the early second trimester until term. As of today there are no normograms of the chin and of the filtrum during pregnancy, and dysmorphism is evaluated only by subjective criteria.

Purpose:  To establish normograms of the fetal chin and filtrum.

Methods:  We studied cross‐sectioned the size of the chin and length of the filtrum in 153 fetuses from the 13th to the 42nd week of gestation. The chin was measured from the lower lip to the skin under the mandibular edge. The filtrum was measured from the nose to the upper lip.

Results:  The growth normograms for the chin was best described by the regression equation: Y = − 9.799 + 1.312X − 0.013 × 2; R2 = 0.87 (Y = chin size in mm, X = gestational week). The growth normograms for the filtrum was best described by the regression equation: Y = − 2.672 + 0.477X − 0.005 × 2, R2 = 0.82 (Y = filtrum size in mm, X = gestational week). The ratio chin/filtrum tends to increase from 2 at the beginning of the second trimester to 2.8 at term.

Conclusions:  We present the first normograms of fetal chin and filtrum along the pregnancy. One of the fetuses was found to have micrognatia at 32 weeks and both his chin and filtrum were abnormal. We used the normograms to evaluate another two past cases of face dysmorphism, which were evaluated by subjective criteria and found abnormal chin and filtrum sizes. These normograms can be used in consulting genetic disorders.
First‐trimester umbilical cord diameter: a novel marker of fetal aneuploidy
Authors: Ghezzi F. , Raio L. , Di Naro E. , Franchi M. , Buttarelli M. , Schneider H.
Published: March 2003

Objective

To compare the umbilical cord diameter at 10–14 weeks of gestation of chromosomally normal and abnormal fetuses.

Methods

In a consecutive series of women, who were undergoing routine sonographic evaluation at 10–14 weeks of gestation, umbilical cord diameter and nuchal translucency were measured. Reference ranges for umbilical cord diameter according to gestational age and crown–rump length were constructed. Fetal karyotype was obtained at chorionic villus sampling, amniocentesis or at delivery in newborns with features suspicious for chromosomal abnormalities.

Results

During the study period, 784 patients met the inclusion criteria. Of these, a fetal or placental chromosomal abnormality was present in 17 cases. The mean umbilical cord diameter increased with gestational age (r = 0.41,P < 0.001). The proportion of fetuses with an umbilical cord diameter above the 95th centile was higher in the presence of fetal or placental chromosomal abnormalities than in normal fetuses (5/17 vs. 39/767, P < 0.01). Among fetuses with an abnormal fetal or placental karyotype, nuchal translucency was above the 95th centile for gestational age in 10 cases. When only fetal chromosomal abnormalities were considered (n = 14), the combined detection rate was 85.7% (12/14).

Conclusions

Sonographic assessment of the umbilical cord in early gestation appears to identify a subset of fetuses at increased risk of chromosomal abnormalities. Copyright © 2002 ISUOG
Pelvic sonography and uterine artery color Doppler analysis in the diagnosis of female precocious puberty
Authors: Battaglia C. , Regnani G. , Mancini F. , Iughetti L. , Venturoli S. , Flamigni C.
Published: March 2003

Objectives

To evaluate the role of ultrasound and color Doppler analyses in the diagnosis of precocious puberty.

Methods

Gray‐scale sonographic uterine and ovarian evaluation together with color Doppler analysis of the uterine artery were prospectively performed in 29 girls presenting with premature breast development and pubic hair growth. The values were compared with results obtained from the gonodotrophin releasing hormone stimulation test. Excluded from the study were patients with isolated thelarche or isolated pubarche and those patients with gonodotrophin releasing hormone‐independent puberty and with polycystic ovaries.

Results

According to the Tanner scale, all the girls presented a breast stage of 2–3 and pubic hair stage 2–3. The uterine size was greater in those girls who presented a pubertal response to the gonodotrophin releasing hormone test (Group II; n = 20) (8.07 ± 4.47 mL) than in those who did not (Group I; n = 9) (3.07 ± 1.18 mL; P = 0.001). The ovarian volume and the number of small follicles was not significantly different between the groups. On Doppler analysis, more elevated impedances were observed in Group I (pulsatility index = 3.28 ± 0.37) than in Group II (pulsatility index = 2.29 ± 0.19; P = 0.001) girls. The presence of a low pulsatility index (<2.5) at the level of the uterine arteries had a high diagnostic value for precocious puberty (sensitivity 86%, specificity 100%).

Conclusions

Uterine artery Doppler analysis may assist the diagnosis of gonodotrophin releasing hormone‐dependent precocious puberty, may be useful for the selection of those girls needing treatment, and may simplify the follow‐up of girls treated for precocities. Copyright © 2002 ISUOG
The sonographic approach to the detection of fetal cardiac anomalies in early pregnancy
Authors: Bronshtein M. , Zimmer E. Z.
Published: March 2003

Background

Transvaginal sonography enables imaging of the fetal heart in various planes and directions in early pregnancy. This study summarizes our experience in early detection of fetal cardiac anomalies.

Methods

Transvaginal sonographic examination was performed in 36 323 consecutive fetuses in both high‐ and low‐risk pregnancies. More than 99% of cases were evaluated at 14–16 weeks' gestation. Examination of the cardiovascular system did not rely on still images of the classic views but instead was performed in a dynamic mode visualizing the heart and great vessels from different directions and in various scanning planes.

Results

Cardiac anomalies were detected in 173 fetuses, giving an overall incidence of 1 in 210 pregnancies. In 44% of these, the cardiac anomaly was isolated. An abnormal karyotype was detected in 27 of the 72 cases that underwent chromosomal analysis. An abnormal nuchal translucency finding was observed in 59 fetuses. The sonographic diagnosis was confirmed after delivery or at postmortem in 90 cases. Ten fetuses had a cardiac anomaly which differed from the anomaly suggested by sonography. In the remaining cases, a postmortem examination was not possible because termination of pregnancy was performed by dilatation and curettage. In four cases we did not detect the cardiac anomaly in early pregnancy. Two of them were detected at rescanning in mid‐pregnancy.

Conclusion

Early detection of fetal cardiac anomalies is now possible. Most anomalies occur in low‐risk pregnancies. We suggest performing a detailed early multidirectional dynamic continuous sweep ultrasound examination of the fetal cardiovascular system in all pregnancies. Copyright © 2002 ISUOG
Evaluation of cycle‐to‐cycle variation of endometrial responsiveness using transvaginal sonography in women undergoing assisted reproduction
Authors: Basir G. S. , O W.‐S. , So W. W. K. , Ng E. H. Y. , Ho P. C.
Published: March 2003

Objectives

To investigate the variation of endometrial responsiveness between cycles within the same women undergoing assisted reproduction.

Methods

The sonographic endometrial thickness in ovarian stimulation cycles was compared with that of subsequent natural cycles. One hundred and thirty‐six ovarian stimulation cycles of in‐vitro fertilization and embryo transfer were evaluated. Women who did not conceive in in‐vitro fertilization cycles were subsequently seen in natural cycles (n = 97) or the next in‐vitro fertilization cycle (n = 39). Based on a receiver–operating characteristics (ROC) curve using endometrial thickness to predict pregnancy, the first in‐vitro fertilization cycles were classified according to the endometrial thickness as optimal (>8 mm) in 98 cycles, or suboptimal (≤8 mm) in 29 cycles. Similarly, spontaneous cycles were classified as suboptimal (≤7 mm) in 28 cycles and optimal (>7 mm) in 69 cycles.

Results

The pregnancy rates were significantly lower (P < 0.05; Fisher's Exact test) in the suboptimal group in both the in‐vitro fertilization and frozen embryo transfer cycles. There was a strong correlation (r
2 = 0.745) and a significant difference (P < 0.001; Wilcoxon signed rank sum test) between the endometrial thickness of stimulation and natural cycles.

Conclusion

It is possible to predict the occurrence of optimal or suboptimal endometrial response in natural cycles of women, after evaluation in stimulated cycles, with a high degree of reliability. Risk of implantation failure can be identified before subsequent treatment cycles and adjuvant therapeutic strategies may be planned to improve the endometrial response before embryo transfer. Copyright © 2002 ISUOG
Antenatal diagnosis of placenta percreta with planned in situ retention and methotrexate therapy in a woman infected with HIV
Authors: Henrich W. , Fuchs I. , Ehrenstein T. , Kjos S. , Schmider A. , Dudenhausen J. W.
Published: March 2003

Placenta percreta is a rare obstetric condition associated with potentially life‐threatening hemorrhage. Diagnosis in advance of delivery permits a planned delivery and preparation for blood transfusions and planned Cesarean hysterectomy, which is the common treatment. We report a case of placenta percreta in an HIV‐positive patient which was diagnosed in the second trimester using conventional and extended field of view ultrasound imaging and color Doppler. At 36 weeks the infant was delivered by Cesarean section and the placenta was left in situ. Postoperatively the patient was treated with methotrexate. Four weeks later, the patient delivered the placenta spontaneously. Early or late postpartum hemorrhage did not occur and postoperative recovery was uneventful. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
First‐trimester, three‐dimensional transvaginal ultrasound volumetry in normal pregnancies and spontaneous miscarriages
Authors: Acharya G. , Morgan H.
Published: March 2003

Objective

The aim of this study was to perform three‐dimensional ultrasound volumetry of intrauterine contents in cases of normal and failed pregnancies and correlate these with conventional two‐dimensional measurements.

Methods

This was a cross‐sectional observational study. Three‐dimensional volumetric data were collected from a total of 111 patients with first‐trimester singleton pregnancies together with conventional two‐dimensional measurements. A single investigator performed all ultrasound scans and volume measurements.

Results

Among 111 participants, 30 had an ongoing pregnancy and 81 had a miscarriage (anembryonic pregnancy 30, missed miscarriage 30, and incomplete miscarriage 21). There were no significant differences in age, parity, or gestational age between groups. A positive linear correlation was demonstrable between the crown–rump length and gestational sac volume in normal pregnancies (r = 0.962) and between gestational sac volume and gestational age, but the correlation was weaker in cases of missed miscarriage (r = 0.561). The volume of the retained products of conception as measured by three‐dimensional ultrasound volumetry in cases of incomplete miscarriage also showed a strong linear correlation (r = 0.938) to their maximum anterior–posterior diameter. There was an exponential correlation between the mean gestational sac diameter and gestational sac volume and the crown–rump length and embryonic volume in cases of both normal and failed pregnancies. The mean gestational sac diameter:crown–rump length ratio (P = 0.008) and gestational sac volume:embryonic volume ratio (P = 0.023) in missed miscarriages were significantly higher than those in ongoing pregnancies.

Conclusion

Three‐dimensional ultrasound volumetry of intrauterine contents in normal and failed pregnancies correlates well with conventional two‐dimensional measurements. Volumetric assessment does not seem to improve the diagnosis of miscarriage. However, its potential to predict pregnancies that will fail and determine the appropriate management regime for individual patients merits further research. Copyright © 2002 ISUOG
Sonographic features of phyllodes tumors of the breast
Authors: Chao T.‐C. , Lo Y.‐F. , Chen S.‐C. , Chen M.‐F.
Published: March 2003

Objective

The aim of this study was to examine the sonographic features of phyllodes tumors of the breast.

Methods

Retrospective analysis of prospectively recorded sonographic features was performed on 2268 patients with phyllodes tumors or fibroadenomas during 1995–98. Data from 110 phyllodes tumors (76 benign, 11 borderline, 23 malignant) and 2204 fibroadenomas were analyzed.

Results

The patients with phyllodes tumors were older than the patients with fibroadenoma (mean ± standard error, 39.7 ± 1.1 years vs. 33.4 ± 0.3 years; P < 0.0001). Sixty‐four percent of patients with phyllodes tumors were aged 31–50 years, while 68.5% of those with fibroadenoma were aged 21–40 years. Phyllodes tumors were larger than fibroadenomas (5.90 ± 0.43 cm vs. 1.95 ± 0.03 cm; P < 0.0001). The ratio of length to anteroposterior diameter of phyllodes tumors was smaller than the ratio of length to anteroposterior diameter of fibroadenomas (1.72 ± 0.06 vs. 1.89 ± 0.02; P = 0.0105). Seventy‐seven percent of phyllodes tumors were lobulated and 79.5% of fibroadenomas were oval. Lobulated shape of the tumor, heterogeneous echo pattern and absence of microcalcification are significant independent sonographic features in multiple logistic regression analysis to distinguish between phyllodes tumors and fibroadenoma. Benign, borderline and malignant phyllodes tumors displayed no significant differences in tumor size or the ratio of length to anteroposterior diameter.

Conclusions

There is a substantial overlap in the sonographic characteristics between phyllodes tumors and fibroadenoma of the breast. If lobulation and heterogeneous hypoechoic internal echoes are observed and calcifications are absent, a diagnosis of phyllodes tumors should be considered. Sonography cannot distinguish between malignant, borderline and benign phyllodes tumors. Copyright © 2002 International Society of Ultrasound in Obstetrics and Gynecology
Lectin binding patterns of porcine oviduct mucosa and endometrium during the oestrous cycle
Authors: WALTER INGRID , BAVDEK S.
Published: March 2003

Important functions of the oviduct during reproduction include the provision of an optimal environment for gametes and zygotes and nutrition of the early embryo. These functions are ensured by the secretion of an oviductal fluid which is known to contain organ‐specific glycoproteins. Glycoconjugates of the apical glycocalyx are considered to play a major role in cell recognition and interaction processes. In the present investigation, binding patterns of Con A, HPA, LTA, RCA I, UEA I, and WGA were studied in defined segments of the oviduct (infundibulum, ampulla, isthmus) and in the uterus during the oestrous cycle. The carbohydrate distribution showed regional as well as time dependent differences. LTA, HPA and WGA reacted strongly with Golgi regions and secretory granules in the oviduct epithelium during the follicular phase, indicating high secretory activity. LTA, HPA, and UEA I also revealed a varying carbohydrate composition of the glycocalyx during the oestrous cycle. Prominent regional differences in glycoconjugate expression were shown in oviductal segments by LTA and HPA binding: during the follicular phase, LTA binding sites were only present on epithelial cells of the isthmic segment, the ampulla and infundibulum being unreactive. D‐N‐acetyl‐galactosamine residues were demonstrated on ciliated epithelial cells of the ampulla and infundibulum exclusively during oestrus. The glycocalyx of uterine epithelial cells was clearly defined by HPA, WGA, LTA, RCA I and UEA I; LTA binding was restricted to the secretory phase. The observation of regional and time dependent variability in glycoconjugate distribution strongly indicates their specific physiological functions in reproductive processes.
Distribution of matrix metalloproteinases and their inhibitor, TIMP‐1, in developing human osteophytic bone
Authors: BORD SHARYN , HORNER ALAN , HEMBRY ROSALIND M. , REYNOLDS JOHN J. , COMPSTON JULIET E.
Published: March 2003

Connective tissues synthesise and secrete a family of matrix metalloproteinases (MMPs) which are capable of degrading most components of the extracellular matrix. Animal studies suggest that the MMPs play a role in bone turnover. Using specific polyclonal antisera, immunohistochemistry was used to determine the patterns of synthesis and distribution of collagenase (MMP‐1), stromelysin (MMP‐3), gelatinase A (MMP‐2) and gelatinase B (MMP‐9) and of the tissue inhibitor of metalloproteinases‐1 (TIMP‐1) within developing human osteophytic bone. The different MMPs and TIMP showed distinct patterns of localisation. Collagenase expression was seen at sites of vascular invasion, in osteoblasts synthesising new matrix and in some osteoclasts at sites of resorption. Chondrocytes demonstrated variable levels of collagenase and stromelysin expression throughout the proliferative and hypertrophic regions, stromelysin showing both cell‐associated and strong matrix staining. Intense gelatinase B expression was observed at sites of bone resorption in osteoclasts and mononuclear cells. Gelatinase A was only weakly expressed in the fibrocartilage adjacent to areas of endochondral ossification. There was widespread but variable expression of TIMP‐1 throughout the fibrous tissue, cartilage and bone. These results indicate that MMPs play a role in the development of human bone from cartilage and fibrous tissue and are likely to have multiple functions.
Morphometric analysis of the postnatal mouse optic nerve following prenatal exposure to alcohol
Authors: DANGATA Y. Y. , KAUFMAN M. H.
Published: March 2003

Pregnant female mice were divided on day 12 post coitum into a control and an experimental group. The experimental group was given a single intraperitoneal dose of 0.015 ml/g body weight of 25% solution of alcohol in distilled water while the control group was exposed to a similar weight related dose of normal saline. The optic nerves were isolated from the offspring of both control and experimental groups at wk 2, 3 and 5 (i.e. during the juvenile period of postnatal development) and analysed by light and electron microscopy. Although in both groups the optic nerve grew in size rapidly during the period studied, the rate of growth in the experimental groups lagged behind that of the controls. The difference was initially significant but tailed off, so that by wk 5 it was no longer significant. The time of initial onset and progression of myelinogenesis in the optic nerve of alcohol exposed mice also lagged behind that of controls. In both groups the size distribution of the myelinated nerve fibres in the optic nerve was unimodal with a positive skewing for all ages. The spectrum of size distribution of the nerve fibres was, however, broader in controls than in the corresponding experimental groups. With increasing age the proportion of small and medium size fibres was greater in the experimental group than in the controls, while for the large diameter fibres the reverse was observed. It is suggested that this study may shed light on the teratogenic effect of ‘binge’ drinking during pregnancy and that it is the critical period when exposure occurs that is more important than the duration of administration.
Quantification of the collagen fibre architecture of human cranial dura mater
Authors: JIMENEZ HAMANN MARIA C. , SACKS MICHAEL S. , MALININ THEODORE I.
Published: March 2003

The purpose of this study was to quantify and map the gross fibre architecture of the cranial dura mater (CDM) using small angle light scattering (SALS). In SALS, HeNe laser light is passed through the tissue, and the resultant scattering pattern is analysed to determine the preferred fibre direction and degree of orientation. The dura mater was found to be a complex structure with fibre orientations ranging from highly aligned to nearly random. In the temporal region, 80% of the samples (n=20) were found to have regions composed of highly oriented fibres with a mean fibre direction of 6.3°±0.8° with respect to the sagittal plane (i.e. almost parallel to the superior sagittal sinus). These highly aligned regions were found in symmetric anatomical locations about the median sagittal sinus and had similar fibre orientations over both hemispheres. Although our sample size was small, we found that the size of the symmetric regions, which covered 14.4±1.6% of the total CDM area, was not influenced by subject's age or sex. The presence of these highly oriented fibre regions in CDM may be due to mechanical forces exerted on dura mater during its development. These forces may have induced realignment of the collagen fibres in the direction of tensile pull, although the exact basis for the unique gross fibre architecture of CDM remains unknown.
A comparison of four in vivo methods of measuring tibial torsion
Authors: MILNER C. E. , SOAMES R. W.
Published: March 2003

Tibial torsion, twisting of the tibia about its longitudinal axis, varies during development and early childhood. Knowledge of the normal range of tibial torsion at various ages and its accurate clinical measurement is important in the assessment of the extent of a torsional deformity. To evaluate tibial torsion a reliable technique for its measurement in vivo is therefore required. The aim of this study was to determine which of 4 existing in vivo methods of measuring tibial torsion was the most accurate and had the highest repeatability, by comparing them with direct measurement of the tibia. A wide range of mean values for tibial torsion was observed, using the various techniques, with none of the indirect techniques employed having a strong correlation with direct measurement of tibial torsion. The repeatability of the indirect techniques was observed to be low both in cadavers (n=4) and the living (n=3). Since none of the in vivo techniques appear to measure true tibial torsion or be of a reasonable repeatability, alternative easy to use and inexpensive methods need to be developed. Accurate clinical measurement of tibial torsion is important in the assessment of the extent of a torsional deformity. It is recommended that data gained using the methods reviewed here are interpreted with caution.
The menisci of the knee joint. Anatomical and functional characteristics, and a rationale for clinical treatment
Authors: MESSNER KAROLA , GAO JIZONG
Published: March 2003

The menisci and their insertions into bone (entheses) represent a functional unit. Thanks to their firm entheses, the menisci are able to distribute loads and therefore reduce the stresses on the tibia, a function which is regarded essential for cartilage protection and prevention of osteoarthrosis. The tissue of the hypocellular meniscal body consists mainly of water and a dense elaborate type I collagen network with a predominantly circumferential alignment. The content of different collagens, proteoglycans and nonproteoglycan proteins shows significant regional variations probably reflecting functional adaptation. The meniscal horns are attached via meniscal insertional ligaments mainly to tibial bone. At the enthesis, the fibres of the insertional ligaments attach to bone via uncalcified and calcified fibrocartilages. This anatomical configuration of gradual transition from soft to hard tissue, which is identical to other ligament entheses, is certainly essential for normal mechanical function and probably protects this vulnerable transition between 2 biomechanically different tissues from failure. Clinical treatment of meniscal tears needs to be based on these special anatomical and functional characteristics. Partial meniscectomy will preserve some of the load distribution function of the meniscus only when the meniscal body enthesis entity is preserved. Repair of peripheral longitudinal tears will heal and probably preserve the load distribution function of the meniscus, whereas radial tears through the whole meniscal periphery or more central and complex tears may be induced to heal, but probably do not preserve the load distribution function. There is no proof that replacement of the meniscus with an allograft can reestablish some of the important meniscal functions, and thereby prevent or reduce the development of osteoarthrosis which is common after meniscectomy. After implantation, major problems are the remodelling of the graft to inferior structural, biochemical and mechanical properties and its insufficient fixation to bone which fails to duplicate a normal anatomical configuration and therefore a functional meniscal enthesis.
A strong myelin thickness‐axon size correlation emerges in developing nerves despite independent growth of both parameters
Authors: FRAHER J. , DOCKERY P.
Published: March 2003

The axon determines whether or not it is myelinated by the Schwann cell. At maturity there is a positive correlation between sheath thickness and axon calibre. This correlation is initially very low or absent, but gradually strengthens during development. This increase could come about because the axon continuously controls Schwann cell myelinating activity, so that a given axon calibre is associated with a particular myelin sheath thickness, an interaction which would entail the Schwann cell continuously monitoring and responding to axon size. This seems unnecessarily complex. This theoretical study shows that the strong correlation between the 2 parameters within a given myelinated fibre population may come about in a much simpler way than outlined above. This is demonstrated by modelling the growth and myelination of a hypothetical population, utilising data from earlier studies on cervical ventral motoneuron axon development. The hypothesis tested shows that the only instructive interactions by the axon on the Schwann cell necessary for the strong correlation between the 2 parameters to emerge are for the initiation of myelination, its continuation and its termination. These could result from a single stimulus being switched on, persisting for a time and being switched off. Under this influence, the Schwann cell is assumed to proceed to form the myelin sheath at a constant rate which it itself inherently determines, in the absence of any quantitative influence exerted by the axon. This continues until the stimulus for myelination ceases to emanate from the axon. The validity of the hypothesis is demonstrated, because the resulting myelin‐axon relationships correspond closely to those observed during development.
Neurite outgrowth‐regulating properties of GABA and the effect of serum on mouse spinal cord neurons in culture
Authors: BIRD MARGARET , OWEN ALUN
Published: March 2003

Time‐lapse photography was used to examine the effects of γ‐aminobutyric acid (GABA) on the outgrowth and motility of neurites in cultures from mouse spinal cord. GABA at concentrations of 100, 10 and 1 μm caused significant inhibition of neurite outgrowth and the motility of growth cones was significantly reduced by treatment with 100 and 10 μm GABA. This effect was mimicked by the GABAB receptor agonist baclofen, whereas the GABAA receptor agonist muscimol had no effect. The effect of GABA on outgrowth and motility seems to be dependent on the type of serum employed. The results reported here were obtained only when heat‐inactivated serum was used and not when non heat‐inactivated serum was added to the culture medium. They suggest that GABA has a role in the regulation of process outgrowth within the embryonic mouse spinal cord.
The consistent presence of the human accessory deep peroneal nerve
Authors: KUDOH HIROYUKI , SAKAI TATSUO , HORIGUCHI MASAHARU
Published: March 2003

Twenty‐four human legs were dissected macroscopically to study the morphological details of the accessory deep peroneal nerve. This nerve arose from the superficial peroneal nerve and descended in the lateral compartment of the leg, deep to peroneus longus along the posterior border of peroneus brevis. Approaching the ankle joint, this nerve passed through the peroneal tunnels to wind around the lateral malleolus; it then crossed beneath the peroneus brevis tendon anteriorly to reach the dorsum of the foot. The accessory deep peroneal nerve was found in every case examined and constantly gave off muscular branches to peroneus brevis and sensory branches to the ankle region. In addition, this nerve occasionally had muscular branches to peroneus longus and extensor digitorum brevis, and sensory branches to the fibula and the foot. The anomalous muscles around the lateral malleolus were also innervated by this nerve. Neither cutaneous branches nor communicating branches with other nerves were found. The present study reveals that the accessory deep peroneal nerve is consistently present and possesses a proper motor and sensory distribution in the lateral region of the leg and ankle. It is not an anomalous nerve as has previously been suggested.
CT examination of the manipulation system in the giant panda (Ailuropoda melanoleuca)
Authors: ENDO HIDEKI , HAYASHI YOSHIHIRO , YAMAGIWA DAISHIRO , KUROHMARU MASAMICHI , KOIE HIROSHI , YAMAYA YOSHIKI , KIMURA JUNPEI
Published: March 2003

The manipulation mechanism of the giant panda (Ailuropida melanoleuca) was examined by means of CT (computed tomography) and 3‐dimensional (3‐D) Volume Rendering techniques. In the 3‐D images of the giant panda hand, not only the bones but also the muscular system was visualised. Sections of the articulated skeleton were obtained. It was demonstrated that the hand of the panda is equipped with separately moulded manipulation units as follows: (1) the radial sesamoid (RS), the radial carpal, and the first metacarpal (R–R–M) complex; and (2) the accessory carpal (AC) and the ulnar (A–U) complex. When the giant panda grasps anything, the R–R–M complex strongly flexes at the wrist joint, the RS becomes parallel with the AC, and the phalanges bend and hold the object. It is shown that the well‐developed opponens pollicis and abductor pollicis brevis muscles envelop and fix the objects between the R–R–M complex and the phalanges during grasping.
Morphometric and ultrastructural changes with ageing in mouse peripheral nerve
Authors: CEBALLOS DOLORES , CUADRAS JORDI , VERDÚ ENRIQUE , NAVARRO XAVIER
Published: March 2003

Qualitative and quantitative information is reported on the morphological changes that occur in nerve fibres and nonneuronal cells of peripheral nerve during the lifetime of the mouse. Tibial nerves of mice aged 6–33 mo were studied. With ageing, collagen accumulates in the perineurium and lipid droplets in the perineurial cells. Macrophages and mast cells increase in number, and onion bulbs and collagen pockets are frequently present. Schwann cells associated with myelinated fibres (MF) slightly decrease in number in parallel with an increase of the internodal length from 6 to 12 mo, but increase in older nerves when demyelination and remyelination are common. The unmyelinated axon to myelinated fibre (UA/MF) ratio was about 2 until 12 mo, decreasing to 1.6 by 27 mo. In older mice, the loss of nerve fibres involves UA (50% loss of 27–33 mo cf. 6 mo) more markedly than MF (35%). In aged nerves wide incisures and infolded or outfolded myelin loops are frequent, resulting in an increased irregularity in the morphology of fibres along the internodes. In the mouse there is an adult time period, 12–20 mo, during which several features of degeneration progressively appear, and an ageing period from 20 mo upwards when the nerve suffers a general disorganisation and marked fibre loss.
Ultrastructural study on the follicle‐associated epithelium of nasal‐associated lymphoid tissue in specific pathogen‐free (SPF) and conventional environment‐adapted (SPF‐CV) rats
Authors: JEONG KWANG IL , SUZUKI HODAKA , NAKAYAMA HIROYUKI , DOI KUNIO
Published: March 2003

Membranous (M) cells in follicle‐associated epithelium (FAE) play an important role in the mucosal immunity through transport of a variety of foreign antigens to the underlying mucosa‐associated lymphoid tissue (MALT). We aimed to investigate the ultrastructure of M cells in the FAE covering nasal‐associated lymphoid tissue (NALT) both in specific pathogen‐free (SPF) rats and in conventional environment‐adapted (SPF‐CV) rats aged 8–38 wk. In NALT of both SPF and SPF‐CV rats, FAE included the nonciliated microvillous cell, which appears to be an analogue of M cell previously described in other MALT. In SPF rats, M cells increased in number only slightly with age, and they maintained morphological uniformity irrespective of age. In SPF‐CV rats, M cells selectively increased in number resulting in prominent expansion of FAE surface area in parallel with the duration of maintenance in a conventional environment. In addition, M cells in SPF‐CV rats showed heterogeneity in their surface morphology such as the length and number of microvilli and cell surface area and outline. In addition, the FAE was stratified by various subtypes of M cells, which were characterised by several subcellular alterations including the presence of many keratin filaments, homogeneous dark bodies and extensive cytoplasmic interfoliation with wide intercellular spaces filled with amorphous proteinaceous material. These characteristics of M cells in SPF‐CV rat were intimately related with a preferential influx of immunocompetent cells into the FAE, which was not seen or was very rare in SPF rats irrespective of age. The results suggest the possibility that NALT may effectively carry out the mucosal immune response against antigenic stimuli of different magnitude through the unique dynamics of M cells which seem to be influenced by the infiltration of immunocompetent cells.
Using diagnostic radiology in human evolutionary studies
Authors: SPOOR FRED , JEFFERY NATHAN , ZONNEVELD FRANS
Published: March 2003

This paper reviews the application of medical imaging and associated computer graphics techniques to the study of human evolutionary history, with an emphasis on basic concepts and on the advantages and limitations of each method. Following a short discussion of plain film radiography and pluridirectional tomography, the principles of computed tomography (CT) and magnetic resonance imaging (MRI) and their role in the investigation of extant and fossil morphology are considered in more detail. The second half of the paper deals with techniques of 3‐dimensional visualisation based on CT and MRI and with quantitative analysis of digital images.
The human vomeronasal organ. Part II: prenatal development
Authors: SMITH TIMOTHY D. , BHATNAGAR KUNWAR P.
Published: March 2003

During the 20th century, the human vomeronasal organ (VNO) has been controversial regarding its structure, function, and even identity. Despite reports that provide evidence for its presence throughout prenatal and postnatal ontogeny, some studies and numerous textbooks declare its absence in late fetal and postnatal humans. To that end, the present study was designed to establish firmly whether the human VNO is homologous with that of other mammals and whether it degenerates (partially or completely) or persists throughout prenatal development. Fifty human embryos and fetuses (33 d to 32 wk fertilisation age) and 2 neonates were examined by light microscopy. Four embryonic primates (mouse lemurs) were examined for a comparison of VNO embryogenesis. The presence or absence and structural characteristics of the VNO and supporting tissues are described. The first appearance of the VNO was in the form of bilateral epithelial thickenings of the nasal septum, the vomeronasal primordium. The primordia invaginated between 37 and 43 d of age and formed the tubular VNO. The tubular VNO was located dorsally at a variable distance from, but was always spatially separated from the paraseptal cartilages. The mouse lemurs examined in this study and other reports from the literature indicate that the human VNO resembles that of primates having functional VNOs until just after a tubular VNO is formed. Examination of the VNO and adjacent tissues suggested that the VNO may lose receptor cells and corresponding vomeronasal nerves and become a ciliated, pseudostratified epithelium between ∼ 12 and 14 wk of age. Our findings indicate the prenatal human VNO goes through 3 successive stages: early morphogenesis, transformation (of the epithelium), and growth. These observations indicated that (1) all embryonic humans develop a vomeronasal organ which is homologous with the VNOs of other mammals, but which has become displaced and highly variable in relative location during embryogenesis; (2) the human vomeronasal organ does not degenerate prenatally, but very likely loses the functional components of the vomeronasal complex of other mammals; and (3) the remnant of the human VNO persists until birth and beyond.
Mouse granulated metrial gland cells require contact with stromal cells to maintain viability
Authors: STEWART I. J.
Published: March 2003

Granulated metrial gland (GMG) cells differentiate in the uterine wall in pregnancy in mice but the mechanisms which control their differentiation and maintenance are unknown. In vivo, GMG cells share an intimate association with fibroblast‐like stromal cells. The importance of this association has been assessed by examining the effects of withdrawal of stromal cell contact on GMG cell maintenance in vitro. When single cell suspensions of cells were prepared from mouse metrial glands there was a steady decline in numbers with days of culture but usually some remained at 7 d of culture. The ability of metrial gland cells to kill Wehi 164 target cells in 51Cr‐release cytotoxicity assays was retained by cells cultured for at least 3 d. When explants of metrial gland were maintained in culture to allow GMG cell migration onto the culture flask, the attached GMG cells were lost by 1 d later. Overall, these results suggest that a juxtacrine regulatory mechanism maintains GMG cells. The rapid loss of unsupported GMG cells in culture has major implications in the design of assays to examine GMG cell function.
An integrated theory of ageing in the nematode Caenorhabditis elegans
Authors: GEMS DAVID
Published: March 2003

Numerous theories of ageing have been proposed, and many have been tested experimentally, particularly using nematode models such as Caenorhabditis elegans. By combining those theories of ageing that remain plausible with recent findings from studies of C. elegans life span mutants, an integrated theory of ageing has been devised. This is formed from 3 interconnected elements: the evolutionary theory of ageing, the oxidative damage theory of ageing, and a nonadaptive programmed ageing theory. This tripartite theory of ageing gives rise to a number of predictions that may be tested experimentally.
Glial fibrillary acidic protein and vimentin immunoreactivity of astroglial cells in the central nervous system of adult Podarcis sicula (Squamata, Lacertidae)
Authors: LAZZARI MAURIZIO , FRANCESCHINI VALERIA
Published: March 2003

The present immunoperoxidase cytochemical study describes the distribution of glial intermediate filament molecular markers, glial fibrillary acidic protein (GFAP) and vimentin, in the brain and spinal cord of the adult lizard, Podarcis sicula. GFAP immunoreactivity is abundant and the positive structures are mainly represented by fibres of different lengths which are arranged in a rather regular radial pattern throughout the CNS. They emerge from generally immunopositive radial ependymoglia and are directed from the ventricular wall towards the meningeal surface. The glial fibres give origin to endfeet which are apposed to the blood vessel walls and subpial surface where they form the continous perivascular and subpial glia envelopes, respectively. In the optic tectum and spinal cord, star‐shaped astrocytes coexist with radial glia. In the spinal cord, cell bodies of immunopositive radial glia are displaced from the ependyma. While vimentin immunoreactive elements are almost completely absent in the brain except for a few diencephalic radial fibres, the spinal cord ependyma exhibits a clearly vimentin positivity and no GFAP staining. In the Podarcis CNS the immunocytochemical response of the astroglial intermediate filaments appears typical of mature astroglia cell lineage since it fundamentally expresses GFAP immunoreactivity. Moreover, this immunocytochemical study shows that the Podarcis fibre pattern with predominant radial glial cells is morphologically more immature than in avians and mammalians, a condition suggesting that reptiles represent a fundamental step in the phylogenetic evolution of vertebrate astroglial cells.
There is no loss of motor neurons in the rat spinal cord during postnatal maturation
Authors: LOWRY K. , QUACH H. , WREFORD N. , CHEEMA S. S.
Published: March 2003

Motor neurons are lost during embryonic development, but it remains controversial whether motor neuron cell death occurs during postnatal life. In this study we investigated the effect of postnatal maturation on the number of intact spinal motor neurons in the rat using retrograde labelling with model‐based counting, and an unbiased stereological counting technique. To determine the number of motor neurons innervating a specific forelimb muscle in rats of different postnatal ages FluoroGold was injected into the flexor carpi radialis. Before postnatal day 21 there were higher numbers of retrogradely labelled motor neurons than in adult rats, suggesting a ‘loss’ with postnatal maturation. This loss may be attributed to tracer diffusion to adjacent muscles and to the permeability of the muscle spindle capsule in younger animals. To obtain an unbiased estimate of the number of motor neurons in the C7 and C8 segments of the postnatal rat cervical spinal cord the fractionator/optical disector counting technique was used. This method did not show a loss of spinal motor neurons between birth and adulthood. The main conclusion from this study is that there is no loss of spinal motor neurons during postnatal maturation.
The development and evolution of the pharyngeal arches
Authors: GRAHAM ANTHONY
Published: March 2003

abstract

A muscularised pharynx, with skeletal support, serving the dual functions of feeding and respiration, is a fundamental vertebrate characteristic. Embryologically, the pharyngeal apparatus has its origin in a series of bulges that form on the lateral surface of the embryonic head, the pharyngeal arches, whose development is complex. These structures are composed of a number of disparate embryonic cell types: ectoderm, endoderm, neural crest and mesoderm, whose development must be coordinated to generate the functional adult apparatus. In the past, most studies have emphasised the role played by the neural crest, which generates the skeletal elements of the arches, in directing pharyngeal arch development, but it has also become apparent that the endoderm plays a prominent role in directing arch development. Neural crest cells are not required for arch formation, their regionalisation nor to some extent their sense of identity. Furthermore, the endoderm is the major site of expression of a number of important signalling molecules, and this tissue has been shown to be responsible for promoting the formation of particular components of the arches. Thus vertebrate pharyngeal morphogenesis can now be seen to be a more complex process than was previously believed, and must result from an integration of both neural crest and endodermal patterning mechanisms. Interestingly, this also mirrors the fact that the evolutionary origin of pharyngeal segmentation predates that of the neural crest, which is an exclusively vertebrate characteristic. As such, the evolution of the vertebrate pharynx is also likely to have resulted from an integration between these 2 patterning systems. Alterations in the interplay between neural crest and endodermal patterning are also likely to be responsible for the evolutionary that occurred to the pharyngeal region during subsequent vertebrate evolution.