bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic monitoring of cerebral metabolites during and after transient global ischemia in rats by quantitative proton NMR spectroscopy in vivo
Authors: Nagatomo Yasushi , Wick Markus , Prielmeier Franz , Frahm Jens
Published: March 2007

Localized proton NMR spectroscopy was used to dynamically monitor alterations of cerebral metabolites before, during, and after a 10 min period of global forebrain ischemia in anesthetized rats. Metabolic assessment was based on user‐independent determination of absolute brain concentrations at a nominal temporal resolution of 1.6 min. While the concentrations of N‐acetyl aspartate (neuronal marker), creatines, cholines, and myo‐inositol (glial marker) remained constant, ischemia induced a rapid decline of brain glucose. One hour after reperfusion, glucose recovered to 4.1± 2.2 mmol/kg wet weight significantly above the basal value of 2.3± 1.3 mmol/kg wet weight. Mirroring glucose depletion, lactate increased from 1.0±0.6 to 13.5±1.5 mmol/kg wet weight 10‐15 min after the onset of ischemia. During reperfusion lactate clearance was characterized by a first‐order rate constant of 0.03/min. The time courses of glucose and lactate reflect the rapid onset of anaerobic glycolysis during states of critically diminished blood flow. Assuming complete ischemia the production of lactate from glucose and cerebral glycogen stores yields a brain glycogen concentration of 4.7±0.9 mmol glycosyl unit/kg wet weight. Elevation of brain glucose during early reperfusion suggests a transient mismatch of glucose uptake and consumption during the first 1‐2 hours post ischemia.
Interpretation of DW‐NMR data: Dependence on experimental conditions
Authors: Norris David G. , Niendorf Thoralf
Published: March 2007

This review examines the effect of experimental conditions on the data obtainable from diffusion weighted NMR experiments. The origin and forms of the Stejskal‐Tanner experiment are presented, and the relative merits of bipolar to monopolar diffusion weighting gradient pulses are discussed, as are those of spin‐echo and stimulated‐echo weighting schemes. The short pulse Stejskal‐Tanner experiment as required for q‐space imaging is described. Criteria for successful diffusion weighted imaging are given, and current strategies for diffusion weighted imaging are evaluated against these. The range of biological objects accessible to diffusion weighted NMR is summarized, together with the associated experimental limitations. In the final section the dependence of diffuson weighted NMR data on diffusion time and b‐value range is examined, and the relationship between apparent restricted diffusion and the size of the extracellular space is demonstrated.
Diffusion‐weighted imaging in tissues: Theoretical models
Authors: Szafer A. , Zhong Jianhui , Anderson Adam W. , Gore John C.
Published: March 2007

Typical diffusion measurements use Stejskal‐Tanner pulsed gradient spin echo sequences to provide information about the average diffusion and displacement profiles of particles in a sample. To derive structural information, a measured displacement profile has to be related by means of a model to the physical and geometrical properties of the tissue, such as diffusion coefficients and shapes of semi‐permeable membranes of compartments in the system. The behavior of the NMR signal and the measured ADC are greatly affected by the cellular architecture of a tissue, mainly because cellular membranes are relatively impermeable to water. For long diffusion times, and small signal attenuations, ADC is relatively insensitive to how it is measured. In general, however, ADC values are not readily interpreted unless the measuring conditions are specified in detail. For given measuring conditions, ADC depends on intra‐ and extracellular diffusion coefficients, membrane permeabilities, cell sizes and the cellular volume fraction. If intra‐ and extracellular T2relaxation rates are different enough, ADC may also depend on the relaxation properties of the system and the echo time. An improved understanding of the precise influence of these factors has been obtained by detailed consideration of theoretical and computer models that can be related to experimental data in simple systems. Further refinements of such models should advance our understanding of water diffusion in tissues.
Diffusion MRI: Precision, accuracy and flow effects
Authors: Conturo Thomas E. , McKinstry Robert C. , Aronovitz Joseph A. , Neil Jeffrey J.
Published: March 2007

After a decade of evolution and application of diffusion imaging, a large body of literature has been accumulated. It is in this context that the accuracy and precision of diffusion‐weighted and quantitative diffusion MRI are reviewed. The emphasis of the review is on practical methods for clinical human imaging, particularly in the brain. The requirements for accuracy and precision are reviewed for various clinical and basic science applications. The methods of measuring and calculating diffusion effects with MRI are reviewed. The pulse gradient spin echo (PGSE) methods are emphasized as these methods are used most commonly in the clinical setting. Processing of PGSE data is reviewed. Various PGSE encoding schemes are also reviewed in terms of the accuracy and precision of isotropic and anisotropic diffusion measurements. The broad range of factors impacting the accuracy of the PGSE methods and other encoding schemes is then considered. Firstly, system inaccuracies such as background imaging gradients, gradient linearity, refocusing RF pulses, eddy currents, image misregistration, noise and dynamic range are considered. A second class of inaccuracies is contributed by the bulk effects of the imaged object, and include sample background gradients, subject motion of cerebrospinal fluid and organs, and aperiodic organ motion. A final category of potential inaccuracies is classified as being contributed by microscopic, biophysical tissue properties and include partial volume effects, anisotropy, restriction, diffusion distance, compartmentation, exchange, multiexponential diffusion decay, T2 weighting and microvascular perfusion. Finally, the application of diffusion methods to studies of blood flow in the microvasculature (i.e. the arterioles, capillaries and venules) are reviewed in detail, particularly in terms of feasibility and the stringent accuracy and precision requirements. Recent provocative studies examining the use of PGSE approaches to suppress microvascular signals in brain functional MRI (fMRI) are also reviewed.
Inferring microstructural features and the physiological state of tissues from diffusion‐weighted images
Authors: Basser Peter J.
Published: March 2007

We review several methods that have been developed to infer microstructural and physiological information about isotropic and anisotropic tissues from diffusion weighted images (DWIs). These include Diffusion Imaging (DI), Diffusion Tensor Imaging (DTI), isotropically weighted imaging, and q‐space imaging. Just as DI provides useful information about molecular displacements in one dimension with which to characterize diffusion in isotropic tissues, DTI provides information about molecular displacements in three dimensions needed to characterize diffusion is anisotropic tissues. DTI also furnishes scalar parameters that behave like quantitative histological or physiological‘stains’ for different features of diffusion. These include Trace(D), which is related to the mean diffusivity, and a family of parameters derived from the diffusion tensor, D, which characterize different features of anisotropic diffusion. Simple thought experiments and geometrical constructs, such as the diffusion ellipsoid, can be used to understand water diffusion in isotropic and anisotropic media, and the NMR experiments used to characterize it.
Diffusion‐weighted NMR imaging: Application to experimental focal cerebral ischemia
Authors: Hoehn‐Berlage Mathias
Published: March 2007

Changes in diffusion NMR imaging are believed to be based on intra/extracellular water homeostasis and will therefore reflect early disturbances of ion and water homeostasis after the onset of an ischemic event. Diffusion‐weighted NMR imaging (DWI) thus has the potential to be a sensitive tool for the observation of stroke evolution. The present state of information extracted from diffusion‐weighted NMR imaging for the understanding of cerebral focal ischemia in experimental research has been compiled in this review. The emphasis was set on three essential aspects of the technique in relation to focal ischemia. Firstly, the sensitivity of diffusion‐weighted imaging for ischemic alterations is described. A comparison with conventional NMR imaging using relaxation time changes is included. Secondly, the comparison of the diffusion‐weighted imaging with invasive techniques is discussed. Here, interpretation of the physiological, metabolic and hemodynamic alterations reflected in the observed diffusion changes is presented. The importance of regionally resolved information for a meaningful assignment of DWI changes to pathophysiological alterations is demonstrated for the differentiation between ischemic core and penumbra from DWI and quantitative diffusion coefficient data. The time dependence of correlations with physiological, biochemical and hemodynamic variables as a further important aspect is stressed. Thirdly, the potential of the technique for the assessment of development and effectiveness of new therapeutical strategies against stroke is demonstrated.
Diffusion‐weighted NMR imaging changes caused by electrical activation of the brain
Authors: Prichard James W. , Zhong Jianhui , Petroff Ognen A. C. , Gore John C.
Published: March 2007

The apparent diffusion coefficient of brain water was decreased by frontal cortical electroshock, usually but not always associated with brief epileptic afterdischarge detectable at the parietal cortex. Previous studies have shown that status epilepticus causes similar larger decreases, which are largely reversible by the termination of seizure discharge with pentobarbital. Cerebral blood flow is elevated in these conditions, and biochemical energy failure does not occur. The brain water diffusion coefficient also decreases in spreading depression, without depletion of energy stores. All of these findings may be due in part to the reduction of brain extracellular space caused by cell swelling, which occurs to some degree in all three conditions. However, major biological differences between brain activation and brain ischemia and new evidence for increased cytosolic viscosity in the latter both suggest that other mechanisms deserve further investigation. Use‐dependent motility of dendritic spines and other phenomena that may allow direct detection of neural activity by diffusion‐weighted NMR imaging are of special interest.
In vivo diffusion spectroscopy. An overview
Authors: Nicolay Klaas , Toorn Annette Van Der , Dijkhuizen Rick M.
Published: March 2007

This review describes in vivo NMR measurements of metabolite diffusion. NMR spectroscopy can employ a variety of endogeneous marker molecules to obtain information on various aspects of in vivo biochemistry and biophysics from the diffusion characteristics of these markers. NMR‐based metabolite diffusion data give an insight into the physico‐chemical properties of the intracellular compartment and of changes therein in relation to development and pathology. Recent applications have proven that in vivo diffusion spectroscopy provides exciting opportunities to both fundamental and applied research.
Clinical Aspects of DWI
Authors: Moseley Michael E. , Butts Kim , Yenari Midori A. , Marks Michael , Crespigny Alex De
Published: March 2007

Diffusion‐weighted MR imaging (DWI) is capable of imaging ischemia‐induced changes in water protons in either animal or man. Technical developments are described that allow the routine clinical utility of DWI in a stroke setting to provide objective criteria beyond the neurological exam by which the pathophysiology of stroke can be evaluated. To date, DWI has provided unique information concerning detection and evaluation of acute, symptomatic lesions from older, chronic strokes, detection and localization of small deep infarcts and reversible ischemic neurologic deficits and transient ischemia. Clinical DWI studies suggest that the temporal behaviour of ADC can critically improve the evaluation of clinical ischemia.
The prenatal diagnosis of the Walker‐Warburg Syndrome
Authors: Crowe Carol , Jassani Majida , Dickerman Lois
Published: March 2007

On the basis of physical features and autopsy findings, a child with congenital hydrocephalus, bilateral microphthalmia, myopathy, severe developmental retardation and multiple brain malformations was diagnosed to have the Walker‐Warburg Syndrome (WWS). During a subsequent pregnancy in this family, a fetus at risk for this autosomal recessive condition was evaluated with serial ultrasound examinations. At 15 weeks of gestation an encephalo‐cele was noted. Disproportionately slow growth of the head compared to the body was noted at 36 weeks. At birth, the diagnosis of WWS was confirmed in the child due to the presence of microcephaly, an encephalocele, a meningocele and bilateral microphthalmia. This is the first reported case of the early prenatal diagnosis of this recently categorized genetic condition, in which the major features are hydrocephalus, multiple central nervous system malformations, microphthalmia with ocular malformations, severe psychomotor retardation, congenital myopathy and a very limited life expectancy.
Prenatal diagnosis of hunter syndrome using chorionic villi
Authors: Pannone N. , Gatti R. , Lombardo C. , Di Natale P.
Published: March 2007

A case of the Hunter syndrome diagnosed prenatally using chorionic villi is presented. Chorion biopsy was performed in the 10th week of pregnancy. The sample was examined for karyotype and for iduronate sulfatase activity. The fetus was male and the enzyme activity reduced to 4 per cent of normal. Termination of pregnancy occurred at the 11th week.
Prenatal diagnosis of a de novo complex chromosomal rearrangement involving four chromosomes
Authors: Kim Hyon Ju , Perle Mary Ann , Bogosian Virginia , Greco Alba
Published: March 2007

A complex chromosome rearrangement, apparently a balanced translocation involving chromosomes 4,6, 15 and 16, was found in cultured cells of amniotic fluid from a 32–year‐old primigravida who requested amniocentesis for prenatal diagnosis because of a family history of mental retardation. Chromosome analysis of peripheral blood from both parents were normal.

The couple was counselled for the prenatal diagnosis of this de novo complex translocation and, subsequently, elected to terminate the pregnancy. Post‐mortem examination revealed a 23–week fetus with intrauterine growth retardation. The identical chromosome rearrangement was subsequently confirmed in cultured fibroblasts from skin and cord obtained from the abortus.

To our knowledge, this is the first report where routine prenatal diagnosis revealed a fetus with a balanced complex chromosomal rearrangement involving four chromosomes of de novo origin.
Congenital chylothorax‐prenatal ultrasonic diagnosis and successful post partum management
Authors: Meizner I. , Carmi R. , Bar‐Ziv J.
Published: March 2007

The prenatal diagnosis by ultrasound of congenital chylothorax is described allowing early intervention immediately after delivery. Unilateral fluid collection in the right lung with marked displacement of the heart to the left were the most prominent sonographic signs. Post partum thoracocentesis and chylus fluid drainage served as a life saving procedure.
Prenatal diagnosis of zellweger's syndrome by chorionic villus sampling‐and a caveat
Authors: Carey W. F. , Robertson E. F. , Van Crugten C. , Poulos A. , Nelson P. V. , Finikiotis G.
Published: March 2007

At 7·5 weeks gestation, two small chorionic villous biopsies were obtained from a woman at risk for Zellweger's cerebro‐hepato‐renal syndrome, and were separately established in culture. After 3 weeks, dihydroxyacetone phosphate acyltransferase (DHAP‐AT) activity was measured in both cultures. The enzyme was markedly deficient in one cell strain and this was subsequently shown to have a male karyotype. However, the second culture had normal enzyme activity and a female karyotype.

The pregnancy was terminated at 11·5 weeks gestation, and follow‐up studies on fetal tissues confirmed a male fetus with markedly deficient DHAP‐AT activity.
Maternal age and amniocentesis: Should this be lowered to 30 years?
Authors: Crandall B. F. , Lebherz T. B. , Tabsh K.
Published: March 2007

We have reviewed the results of 10000 2nd trimester amniocenteses performed at our centre. Over 80 per cent of these were done only because of maternal age (MA); there were three times as many < 35 year‐old women in 1984 compared to 1975. Of women aged 30–34 years at delivery 0·69 per cent were found to have a MA‐related chromosome abnormality compared to 0·94 per cent in those aged 35–40 years. Because only about 7 per cent of births occurred to women ⩾ 35 years and 18·6 per cent between 30–34 years, and a practical utilization rate of 50 per cent, we recommend that amniocentesis be made available to women aged ⩾ 30 years. We believe that 27 per cent of Down syndrome (DS) pregnancies could be identified if 50 per cent of pregnant women in this age category availed themselves of the test. With the same utilization rate, about three times as many amniocenteses would be required in California as performed here in 1983.
Chorionic villus culture for first trimester diagnosis of chromosome defects: Evaluation by two london centres
Authors: Czepulkowski B. H. , Heaton D. E. , Kearney L. U. , Rodeck C. H. , Coleman D. V.
Published: March 2007

The maceration technique for the culture of chorionic villi has been applied by St Mary's Hospital and King's College Hospital, to a total of 225 villus aspirates of which 100 were from diagnostic cases. Two hundred and eighteen (96·8 per cent) of these were successfully karyotyped, and chromosome abnormalities were detected in 15 cases. Of the cases with a normal karyotype, 113 were male and 90 were female. Sixty‐nine (77 per cent) of the female cultures were demonstrated to be fetal and a further two of these may be verified at delivery. The use of Chang medium was found to accelerate cell growth thereby reducing the interval between sampling and reporting to less than 2 weeks. An unlimited quantity of metaphase spreads was obtained suitable for the application of routine banding techniques, and comparable to those obtained from amniotic fluid culture. Experience with diagnostic cases reinforced our view that culture should always back up direct analysis and this is discussed with particular reference to the occurrence of mosaicism in the trophoblast.
Short communication kazal type trypsin inhibitor in amniotic fluid in fetal developmental disorders
Authors: Kolho K. L.
Published: March 2007

The amniotic fluid concentrations of the Kazal type trypsin inhibitor were studied in pregnancies with fetal developmental disorders. The samples were obtained by amniocentesis between 14 and 19 weeks of gestation. In cases with fetal malformations, the level was below the normal 10th centile in 15 out of 28 cases (54 per cent, P<0.05) and above the normal 90th centile in 2 cases (7.1 per cent). Low values were common in cases with intrauterine fetal death or congenital nephrosis. The levels were normal in fetal chromosomal aberrations.
Inv dup (15): Prenatal diagnosis and postnatal follow‐up
Authors: Miny P. , Basaran S. , Kuwertz E. , Holzgreve W. , Pawlowitzki I.‐H.
Published: March 2007

A de novo inv dup (15) was diagnosed at amniocentesis. No physical abnormalities were detected after birth. The boy developed severe mental and motor retardation, which became obvious at 16 months of age.
Prenatal diagnosis of osteogenesis imperfecta type III
Authors: Robinson L. Pat , Worthen Nancy J. , Lachman Ralph S. , Adomian Gerald E. , Rimoin David L.
Published: March 2007

Ultrasonographic and radiographic evaluation of a fetus at risk for osteogenesis imperfecta (O.I) type III was performed. Real‐time ultrasound measurements at 15 weeks gestation were interpreted as normal, but at 20 and 22 weeks of gestation revealed marked shortening of the long bones and deformity of the femurs. The findings were confirmed by fetal radiography at 22 weeks gestation. Radiographic and histologic changes characteristic of O.I. were observed in the aborted fetus. Thus the antenatal manifestations of O.I. type III maybe severe enough to make prenatal diagnosis possible in the second trimester for families at risk for recurrence of this disorder.
First trimester diagnosis of RhO (D) with an immunofluorescence technique after chorionic villus sampling
Authors: Fuhrman H. C. , Klink F. , Grzejszczyk G. , Vossberg A. , Poschmann A. , Geusendam G. , Froster‐Iskenius U. , Schwinger E.
Published: March 2007

Double indirect immunofluorescence technique (DIIF) was applied to fetal erythrocytes from vascularized chorionic villi, obtained by chorionic villus sampling (CVS) in the first trimester of pregnancy, to determine the presence of Rhesus antigen Rh (D).
Prenatal diagnosis of severe combined immunodeficiency with defective synthesis of HLA molecules
Authors: Durandy A. , Cerf‐Bensussan N. , Dumez Y. , Griscelli C.
Published: March 2007

The immunodeficiency associated with a defective expression of HLA molecules is an autosomal recessive disorder leading to death during childhood. We have performed prenatal diagnosis for six fetuses at risk for this disease by membrane immunofluorescence on blood lymphocytes and monocytes, using specific monoclonal antibodies for HLA class I and II molecules. Two pregnancies have been found to be affected. The diagnosis has been confirmed on each abortus by the study of the membrane expression of HLA class I and II molecules on blood lymphocytes and monocytes, and on thymic and splenic cells. The four other cases were found to be normal both during pregnancy and after birth. The detection of the defect as early as the 20th week of gestation allows selective termination.
Temporal changes in Ohio amniocentesis utilization during the first twelve years (1972–1983), and frequency of chromosome abnormalities observed
Authors: Naber John M. , Huether Carl A. , Goodwin Beth A.
Published: March 2007

The history of amniocentesis utilization in the seventh largest state of the United States is documented from its inception in 1972 through the first half of 1984. Amniocentesis utilization ratios for Ohio residents aged ⩾35 have increased from 0.21 per cent (19/9091) in 1972 to 23.4 per cent (1655/7531) in 1983, representing an average annual growth rate of 43.1 per cent. Of the amniocenteses performed from January 1, 1978–July 1, 1984, 71 per cent were referred for advanced maternal age (⩾35), 15 per cent for maternal anxiety (30–34), 10 per cent for family history or previous child with a genetic defect, and 4 per cent for other reasons. Between 1978‐1983 utilization by women 45 years of age was only 20 per cent higher than women 35 even though their risk of giving birth to a Down syndrome child was about one order of magnitude higher. In addition, various factors were tested as to whether they affected utilization of amniocentesis by women ⩾35 during 1978 1983. A strong correlation of +0.89 existed between county population size and utilization ratios. No difference in utilization was found between whites and nonwhites, regardless of county population size. When utilization ratios were compared separately between Protestants, Catholics and other religions in Ohio's most populated county, no statistical differences were found. From 1978–July 1, 1984, the frequency of all cytogenetically abnormal chromosome results observed in Ohio amniocenteses to women ⩾35 was 2.48 per cent (187/7536). Of these, 2.15 per cent (162/7536) had unbalanced karyotypes. Future maximum amniocentesis utilization for women ⩾35 is estimated at 60–70 per cent.
Prenatal diagnosis of mosaic trisomy 9
Authors: Zadeh Touran M. , Peters June , Sandlin Constance
Published: March 2007

Mosaic trisomy 9 was detected in an amniotic fluid cell culture from a 40‐year‐old woman evaluated because of advanced maternal age. After counselling, parents elected to terminate the pregnancy. On autopsy the fetus was found to have hydrocephalus and a single kidney. The diagnosis of trisomy 9 mosaicism was confirmed in cultured skin fibroblasts. This is the third reported case of trisomy 9 mosaicism diagnosed prenatally.
Determination of maternal serum acetylcholinesterase in pregnancies with fetal neural tube defects
Authors: Sorensen K. , Brodbeck U. , Rasmussen A. G. , Norgaard‐Pedersen B.
Published: March 2007

We have investigated the occurrence of acetylcholinesterase (AChE) (E.C.3.1.1.7) in fetal serum, amniotic fluid and maternal serum using an immuno‐chemical assay‐technique employing both polyclonal and monoclonal antibodies. Fetal serum had increased amounts of AChE, which is due to an increase in the 10.5S form of the enzyme. This form was also found in amniotic fluids of pregnancies with a fetal neural tube defect (NTD), but not in normal amniotic fluid. The increase in amniotic fluid AChE was however, not reflected in the maternal serum.
The impact of screening for open neural tube defects in England and Wales
Authors: Cuckle Howard , Wald Nicholas
Published: March 2007

Using information derived from the voluntary system of notification of congenital malformations in England and Wales, the birth prevalence of anencephaly and spina bifida was estimated to have declined by 80 per cent from 31.5 to 6.2 per 10 000 between 1964–1972 and 1985. Over the same period, notified terminations of pregnancy with a suspected fetal central nervous system abnormality increased from less than 1 per cent to 56 per cent of neural tube defect births and central nervous system terminations combined, accounting for 31 per cent of the decline in births. Routinely collected national statistics provide a method for monitoring the impact of screening for open neural tube defects. However because they are incomplete and lack detail an alternative method of monitoring is needed. This paper includes an outline of such a method, together with the results of a pilot study designed to assess the feasibility of monitoring screening in the Oxford Region.
Prenatal diagnosis of alpha‐1‐antitrypsin deficiency by fetal blood sampling
Authors: Corney G. , Whitehouse D. B. , Hopkinson D. A. , Rodeck C. H. , Nicolaides K. , Norman M. , Mowat A. P.
Published: March 2007

Fetal blood sampling for the diagnosis of alpha‐1‐antitrypsin deficiency using protein isoelectric focusing was carried out in the period 1980–1985. The results of 25 cases from 18 mothers are reported. All had a previous history of a PiZ child affected by liver disease.

The method was found to be technically satisfactory and the fetal results were subsequently confirmed in all 18 cases where follow‐up was possible. The fetus was found to be PiZ in nine cases and all these pregnancies were terminated. Of the remaining pregnancies three cases aborted or were delivered prematurely and 13 proceeded to term without complications.
Prenatal diagnosis and obstetrical management of multicystic dysplastic kidney disease
Authors: Rizzo Nicola , Gabrielli Sandro , Pilu Gianluigi , Perolo Antonella , Cacciari Alfredo , Domini Remigio , Bovicelli Luciano
Published: March 2007

Multicystic dysplastic kidney disease (MDKD) is one of the most common congenital renal anomalies. We report 16 consecutive cases of MDKD recognized in the antenatal period by sonography. Diagnosis is usually easy as MDKD has in the vast majority of cases a striking ultrasound appearance including enlargement of the kidney and multiple renal cysts. However, differentiation from obstructive uropathy may be difficult, and we made a total of five erroneous diagnoses. Unilateral MDKD has almost invariably a good prognosis. However, severe life‐threatening associated anomalies were found in six cases. Therefore, a detailed survey of fetal anatomy and determination of karyotype are strongly recommended.
Second trimester prenatal diagnosis of the Jarcho‐Levin syndrome
Authors: Tolmie John L. , Whittle Martin J. , McNay Margaret B. , Gibson Angus A. M. , Connor J. M.
Published: March 2007

The Jarche–Levin syndrome (spondylothoracic dysostosis) is a rare autosomal recessive disorder characterized by a short neck, short trunk and a constricted thorax due to multiple rib and vertebral defects; other visceral malformations are occasionally present. Most cases die in infancy due to respiratory failure. In this report we describe two cases in one family from the United Kingdom. Prenatal diagnosis by ultrasound examination during the second trimester was successfully accomplished in the second case.
Prenatal diagnosis of medium‐chain acyl‐coenzyme A dehydrogenase deficiency
Authors: Bennett M. J. , Allison F. , Lowther G. W. , Gray R. G. F. , Johnston D. I. , Fitzsimmons J. S. , Manning N. J. , Pollitt R. J.
Published: March 2007

A fatal case of medium‐chain acyl‐coenzyme A dehydrogenase deficiency is described in a patient who presented with hypoglycaemia and a gross non‐ketotic dicarboxylic aciduria. Cultured skin fibroblasts released 14CO2 from [1–14C] octanoic acid at half the normal rate. Prenatal diagnosis was undertaken in a subsequent pregnancy in which cultured amniotic fluid cells revealed a marked reduction in octanoate oxidation indicative of an affected fetus. The pregnancy was terminated and the diagnosis was confirmed by enzyme analysis of skin fibroblasts taken from the fetus. The high residual octanoate oxidation by affected fibroblasts together with the absence of any characteristic abnormality of amniotic fluid organic acids are a potential limitation to the reliability of this type of prenatal diagnosis.
Prenatal diagnosis of congenital non‐bullous ichthyosiform erythroderma (lamellar ichthyosis)
Authors: Perry Tracy B. , Holbrook Karen A. , Hoff Mary S. , Hamilton Emily F. , Senikas Vyta , Fisher Chris
Published: March 2007

We report the first positive prenatal diagnosis ofcongenital non‐bullous ichthyosiform erythroderma or lamellar ichthyosis. Fetal skin samples were obtained by fetoscopy at 21 weeks' gestation and examined by light and electron microscopy. Light microscopy revealed a thickened interfollicular epidermis with multiple layers of flattened cells and excessive keratinization of the epidermal lining of the follicular infundibulum. Electron microscopy of the thickened epidermis revealed granular cells that contained larger‐than‐normal keratohyalin granules and multiple layers of parakeratotic cornified cells. Although there was regional variation in the degree of interfollicular keratinization, follicles from all regions showed greater and more complete keratinization, indicating that they express the abnormality early enough in development to permit prenatal diagnosis at about 20 weeks' gestation.
Modulation of echocardiographic parameters by fetal behaviour
Authors: Arduini D. , Rizzo G. , Pennestri F. , Romanini C.
Published: March 2007

In order to verify if fetal behavioural states could affect cardiac parameters, thirty‐one healthy fetuses were studied near term. We evaluated systolic time intervals (pre‐ejection period and ventricular ejection time), M‐mode parameters (fractional shortening and mean circumferential shortening) and Doppler flow velocities (mean peak velocity of aortic and pulmunary arteries) of left and right ventricles. Both fetal breathing movements and fetal heart rate patterns seem to modify these parameters with an increase of cardiac contractility during active phases of fetal behaviour.
Early prenatal diagnosis of A lethal syndrome of multiple congenital contractures
Authors: Kirkinen P. , Hervat R. , Leisti J.
Published: March 2007

An ultrasonic diagnosis of a lethal, autosomally recessive syndrome of multiple congenital contractures was made in seven high‐risk pregnancies on the 13rd to 17th gestational weeks. The diagnostic findings were the development of progressive subcutaneous oedema from the 13th gestational week on and the decrease of fetal limb movements.
Prenatal diagnosis of the fragile X using thymidine induction
Authors: Sutherland Grant R. , Baker Elizabeth , Purvis‐Smith Stuart , Hockey Athel , Krumins Ed , Eichenbaum Sam Z.
Published: March 2007

Eleven pregnancies in ten patients at risk for the fragile X were monitored by amniocentesis or chorion villus biopsy and induction of the fragile site using thymidine, methotrexate and FUdR. Three female fetuses and one male fetus were found to have the fragile X. The results obtained using thymidine induction were superior to those using methotrexate induction and probably better than those obtained using FUdR induction.
A prospective study of spontaneous miscarriage in ultrasonically normal pregnancies and relevance to chorion villus sampling
Authors: Liu David T. Y. , Jeavons B. , Preston C. , Pearson D.
Published: March 2007

A total of 1068 patients were examined by ultrasound to ensure normality of pregnancy and followed prospectively from booking until 28 weeks. The spontaneous miscarriage rate was 2.7 per cent occuring within the first 16 weeks. Threatened miscarriage was associated with a 38 per cent fetal loss. Miscarriage was less likely as pregnancy advanced. The reduction in subsequent miscarriage rate before 11 weeks and from 11 weeks onwards is statistically significant (p<0.001). Gravidity, maternal age and a history of previous fetal loss did not contribute significantly to the miscarriage rate. Patients with a history of fetal loss were more likely to experience a threatened miscarriage. The relevance of these findings to chorion villus sampling is discussed.
Prenatal diagnosis of trisomy 20 mosaicism indicating an extra embryonic origin
Authors: Baldinger Shari , Millard Cindy , Schmeling David , Bendel Richard P.
Published: March 2007

An additional case of amniotic fluid trisomy 20 mosaicism is presented. After careful counselling, the pregnancy continued and a phenotypically normal female was delivered. This case of amniocyte mosaicism establishes the source of aneuploid cell line as amnion. Since an extra‐embryonic origin of the mosaicism has been confirmed, this should be carefully considered as a real possibility in counselling such families.
Listeriosis: A cause of non‐immune hydrops fetalis
Authors: Gembruch U. , Niesen M. , Hansmann M. , Knöpfle G.
Published: March 2007

A case of prenatally diagnosed non‐immune hydrops fetalis, that was later shown to be caused by listeriosis, is presented, and the clinical course, as well as the appropriate diagnostic and therapeutic procedures are described. We conclude, that listeriosis should be excluded, whenever a non‐immune hydrops fetalis is associated with septicemia, influenza‐like illness and fever of unknown origin.
The importance of chorionic villus sampling after first trimester diagnosis of cystic hygroma
Authors: Reuss A. , Pijpers L. , Schampers P. T. F. M. , Wladimiroff J. W. , Sachs E. S.
Published: March 2007

The prenatal diagnosis of The Turner Syndrome is described at a menstrual age of 12 weeks. Detection of cystic hygroma was followed by vaginal chorionic villous sampling (CVS) which revealed a 45,X karyotype. Early documentation of fetal karyotype in the presence of a cystic hygroma is essential for accurate diagnosis and genetic counselling.
Ultrasound evaluation of pregnancies at risk for homozygous α‐thalassaemia‐1
Authors: Ghosh A. , Tang M. H. Y. , Liang S. T. , Ma H. K. , Chan Vivian , Chan T. K.
Published: March 2007

Twenty‐six pregnant Chinese women who were at risk of giving birth to a fetus affected with homozygous α‐thalassaemia‐1 were examined serially by ultrasound. Six of these 26 pregnancies were affected. In one third of the affected pregnancies progressive fetal ascites appeared before 24 weeks gestation and these pregnancies were terminated. In the remaining two thirds abnormal estimated fetal weight‐placental volume (EFW‐PV) ratio and fetal growth retardation as evidenced by a falling biparietal diameter (BPD), femur length (FL) but a normal abdominal circumference (AC) was apparent by 28 weeks gestation. Increased transverse cardiac (TC) diameter was another consistent finding but appeared late. All these features appeared before the onset of fetal ascites. A normal EFW‐PV ratio and fetal growth until 28 weeks gestation was a reassuring sign of normality. Abnormal EFW‐PV ratio was the earliest sign to appear in affected pregnancies and a normal ratio until 28 weeks gestation had a 100 per cent predictive value.
Maternal cell contamination in cultured chorionic villi: Comparison of chromosome Q‐polymorphisms derived from villi, fetal skin, and maternal lymphocytes
Authors: Williams John , Medearis Arnold L. , Chu Weimei H. , Kovacs George D. , Kaback Michael M.
Published: March 2007

Maternal cell contamination of chorionic villi (CV) samples used for first trimester prenatal diagnosis can cause obvious and/or unrecognized diagnostic dilemmas. The purpose of this investigation is to assess the frequency of maternal cell contamination (MCC) in chorionic villus samples and to evaluate selected parameters which might predict where contamination is more likely to have occurred. Maternal lymphocytes, chorionic villi from ultrasonically directed transcervical catheter aspiration, and fetal tissue were obtained at 8–11 weeks gestation from 45 patients undergoing elective termination. Quinacrine (Q) banded metaphases were compared from duplicate direct preparations of chorionic villi; cultured chorionic villi, fetal fibroblast tissue cultures, and maternal lymphocyte cultures. Q‐polymorphisms in metaphase chromosomes were 100 per cent concordant between fetal tissue and direct CV preparation. However, evidence for maternal cell contamination occurred in 13.1 per cent of cultured chorionic villi preparations where polymorphisms were found to be identical between maternal and cultured CV and both distinct from fetal tissue preparations. Where MCC was identified, it was noted that CV cell cultivation interval was prolonged (24.2±6.8 days) compared with non‐contaminated cultures (14.1±4.4 days) (p <0.05).

We conclude that maternal cell contamination is a significant problem with chorionic villus sampling. Where direct preparations are not employed or when cultures are ‘slow growing’, MCC may be a significant and unrecognized complication re: fetal diagnosis. Direct preparations, multiple cultures, quinacrine banding, and maternal Q‐polymorphism comparisons can minimize diagnostic dilemmas secondary to maternal cell contamination. Q‐polymorphism comparisons between maternal and fetal chromosomes should be included in all instances where cultured chorionic villi are utilized for fetal diagnosis and where direct preparations are not available.
Krabbe's disease: First trimester diagnosis confirmed on cultured amniotic fluid cells and fetal tissues
Authors: Giles L. , Cooper A. , Fowler B. , Sardharwalla I. B. , Donnai P.
Published: March 2007

Chorionic villi obtained during the first trimester from a pregnancy at risk for Krabbe's disease were shown to have reduced cerebroside‐β‐galactosidase (E.C. 3.2.1.46) activity using the artificial substrate trinitrophenylaminolauryl galactocerebroside (TNPAL‐galactocerebroside). Assay of this enzyme in cultured amniotic fluid cells following amniocentesis, performed at the patient's request confirmed the diagnosis. Termination of pregnancy was performed and subsequent enzyme studies of the fetal tissues were consistent with the diagnosis of Krabbe's disease, thus confirming that chorionic villi can be used for first trimester diagnosis of this condition.
First Trimester Prenatal Diagnosis of Metabolic Diseases: A survey in countries from the European Community
Authors: Poenaru Livia
Published: March 2007

This paper presents the collected data concerning First Trimester Prenatal Diagnosis of Metabolic Diseases performed in different countries of the European Community by enzymatic methods using chorionic villi.

In all, 258 diagnoses were made for 38 different metabolic diseases and 56 (22 per cent) affected fetuses have been detected.

Several difficulties were encountered with regard to chorionic villus material or enzyme expression in this tissue. We stress the conditions necessary for avoiding errors in diagnosis.
Karyotypic differences between cells from placenta and other fetal tissues
Authors: Verjaal M. , Leschot N. J. , Wolf H. , Treffers P. E.
Published: March 2007

Six cases are reported with discrepancies between the karyotypes of placental cells and cells from other fetal tissue. The respective findings were: (a) 48,+7,+18 resp. 47,+18. (b) 46, i(18q) resp. 46, del18(p11). (c) 46, XX resp. 46, XX/47, XXX. (d) 46, X, Yq+ and 46, XY resp. 46, XY. (e) 46/47,+12 resp. 46. (f) 46/47,+5 resp. 46. These differences were found in both early and term pregnancies. Care should be taken in deducing the fetal karyotype from the chromosomal pattern of placental cells.
Immediate prenatal diagnosis of Zellweger syndrome by direct measurement of very long chain fatty acids in chorionic villus cells
Authors: Rocchiccioli F. , Aubourg P. , Choiset A.
Published: March 2007

We report a gas chromatographic‐mass spectrometric method which allows the very long chain fatty acids content of trophoblastic tissue to be directly measured in samples collected by biopsy between 8 and 11 weeks of gestation. This method has been successfully applied to the detection of fetal Zellweger syndrome in two pregnant women who had previously delivered affected infants. In one of them, increased concentrations of C26:0 (0.254 versus 0.108±0.035 μ/mg proteins) and C24:0 (1.32 versus 0.815±0.325 μ/mg proteins) in trophoblast indicated that the fetus had Zellweger syndrome, a diagnosis confirmed by pathological findings after abortion. In the second case, the pregnancy was allowed to proceed, on the basis of normal concentrations of very long chain fatty acids in trophoblastic tissue, and its outcome was actually a healthy newborn.
Incidence of fetal chromosome abnormalities in 2264 low‐risk women
Authors: Tabor Ann , Philip John
Published: March 2007

Among a population of 6305 pregnant women, aged 25 to 34 years and estimated to be at no increased risk of genetic disease in the fetus, 4606 women participated in a randomized controlled trial of genetic amniocentesis between 1980 and 1984.

In the study group having amniocentesis (2264 women), 23 fetal chromosome abnormalities (1.0 per cent) were found: eight autosomal aneuploidies, seven sex chromosome aneuploidies, seven balanced structural rearrangements and one case of a marker some. The structural rearrangements and the marker chromosome were all shown to be inherited. The study group seemed representative for the whole population of younger women at low genetic risk. Therefore, a 1.0 per cent total rate of fetal chromosome abnormalities, consisting of one‐third autosomal aneuploidies, one‐third sex chromosome aneuploidies and one‐third structural rearrangements, may be expected in the second trimester in younger low‐risk women.

In the same period of time, 562 women in the same age group were offered amniocentesis because of an estimated increased risk of fetal genetic disease. The total rate of fetal chromosome abnormality in this ‘high‐risk’ group was 0.9 per cent and thus no different from the rate in the low‐risk group.
High resolution proton NMR spectroscopy of human amniotic fluid
Authors: Nelson T. R. , Gillies R. J. , Powell D. A. , Schrader M. C. , Manchesters D. K. , Pretorius D. H.
Published: March 2007

Human amniotic fluid (HAF) is a dynamic system whose characteristics depend on continuous interchanges between fetal and maternal circulations. HAF reflects not only the environment of the fetus but may also provide information about fetal development or pathology. The concentration of HAF constituents varies with gestational age and pathological states. The number of the compounds currently implicated in fetal developmental pathology are relatively few. Currently used assay methods are not adequate to totally explain or predict the complex biochemistry of the fetus. The purpose of this work was to investigate HAF with NMR spectroscopy. In the present study HAF was obtained from 47 women undergoing routine amniocentesis. Cells were separated for karyological analysis and the supernatant was acid‐extracted, lyophilized and re‐suspended in D20 resulting in a concentration increase over native fluid. 1H NMR spectra were obtained at 360 MHz and 60 MHz. Eighteen compounds including several amino acids, were identified using parallel reference and standard addition protocols. NMR spectroscopy detected compounds of known clinical importance including glucose, leucine, isoleucine, lactate and creatinine. In conclusion, we have demonstrated that a number of physiologically relevant compounds are readily observable in HAF using 1H NMR spectroscopy. This technique can currently provide valuable information regarding HAF composition and has the potential of being used in vivo in the future.
Prenatal detection of a de novo duplication of the long arm of chromosome 7
Authors: Howard P. J.
Published: March 2007

Amniocentesis was performed for maternal age and subsequent cytogenetic studies revealed a male fetus with a mosaic karyotype, one cell line having a duplication for the long arm of chromosome 7.

The pregnancy was terminated and the two cell lines confirmed in varying proportions in the fetal tissues. External examination of the fetus revealed only growth retardation and a high forehead. The lack of phenotypic defects and the possible aetiology of the de novo rearrangement are considered.
Misdiagnosis of omphalocele associated with Edwards syndrome and congenital heart disease
Authors: Colley N. , Knott P. D. , Gould S. J.
Published: March 2007

We present a case in which an apparent omphalocele, diagnosed at 30 weeks gestation ultrasound, led to identification of fetal trisomy 18 and congenital heart disease. At delivery, the fetus had the features of trisomy 18 and congenital heart disease but the omphalocele was absent. We suggest that the appearances seen are easily confused with a small omphalocele and could potentially result in unnecessary further investigations being performed.
A simple method for preparing prometaphase chromosomes from amniotic fluid cell cultures
Authors: Cheung Sau W. , Crane James P. , Johnson Ann , Simms Lyn , Reid Joan
Published: March 2007

A simple method for preparing prometaphase chromosomes from amniotic fluid cell cultures is described. The technique is based upon several key steps including: (1) reduced colcemid concentration, (2) reduced exposure to trypsin‐EDTA, and (3) maintaining cells in single suspension by adjusting cell concentration appropriately. Chromosomes with banding resolution up ot 800 bands per haploid set can be routinely produced. The described methodology is particularly useful in defining and establishing the clinical significance of subtle structural aberrations.
Prenatal diagnosis of tuberous sclerosis: The use of fetal echocardiography
Authors: Platt Lawrence D. , Devore Greggory R. , Horenstein Janet , Pavlova Zdena , Kovacs Bruce , Falk Rena Ellen
Published: March 2007

Fetal echocardiography was used to identify a cardiac rhabdomyoma in the second trimester. The combination of this finding with a maternal history of Tuberous Sclerosis allowed the patient and her family to make a more educated decision regarding termination of the pregnancy. Post mortem examination of the fetus confirmed the prenatal findings. This case report demonstrates the importance of ultrasound evaluation of the fetus at risk of recurrence of a genetic syndrome in which one or more anatomical defects might be seen.