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PubMed2003

Peripheral sensory and motor abnormalities in patients with multiple sclerosis.

OBJECTIVES: Peripheral nerve abnormalities are uncommon in multiple sclerosis (MS). When present, they are usually attributed to factors associated with advanced disease, such as malnutrition or cytotoxic drugs or hereditary factors. However, a combination of MS and neuropathy has been reported. The aim of this study is to evaluate the question of possible peripheral involvement in MS. METHODS: We studied sensory and motor nerve conduction velocities (NCV) and amplitudes values in some sensory and motor nerves in upper and lower extremities in 20 definite multiple sclerosis patients diagnosed according to the criteria of Poser Scale and in 15 healthy subjects. The total number of studied nerves were 91 in patients group and 69 in control group. RESULTS: The most frequent electrophysiological abnormalities noted in patients group were low amplitude of the ulnar and sural nerve and slow NCV of the tibial and sural nerves. Electrophysiological abnormalities were found in 15 of 91 nerves examined (16.5%). The neurological disability was not associated with the presence of electrophysiological abnormalities. The electrophysiological abnormalities in control group subjects were a slight slow conduction of sural nerve in 2 of 69 nerves examined (2.9%). CONCLUSIONS: Our findings indicate a high frequency of sensory-motor electrophysiological nerve abnormalities in a selected group of multiple sclerosis patients. Electromyographers must be aware of these abnormalities when performing routine electromyography examinations in these patients.

Adult↗

PubMed2002

[Neuroimaging and neurochemical studies of Rett syndrome].

We review here the current status of neuroimaging and neurochemical research on Rett syndrome (RTT), with reference to neurophysiological, neuropathological, and immuno-histochemical changes previously described. Abnormalities have been reported in the intermediates of the biogenic amine neurotransmitters/receptor systems, and of beta-phenylethylamine (PEA), an endogenous amine synthesized by the decarboxylation of phenylalanine in dopaminergic neurons of the nigrostratal system. We also discuss the roles of other neurotransmitters including beta-endrophin, substance P and neurotrophic factors including nerve growth factors. Recently, mutations in the gene encoding methyl-CpG binding protein 2 (MeCP2), mapped to Xq28, have been identified in patients with RTT. Multiple abnormalities in various neurotransmitter/receptor systems may accounts for the pervasive defects in RTT.

Biogenic Amines↗

PubMed1992

Hyperparathyroidism in multiple endocrine neoplasia syndrome.

BACKGROUND: We analyzed clinical findings and results of parathyroidectomy in 42 patients treated from 1936 to 1988 at the University of California, San Francisco (UCSF) for primary hyperparathyroidism and multiple endocrine neoplasia (MEN) syndrome to document results of parathyroidectomy and reasons for failed parathyroid operations. METHODS: Of the 42 patients (38 had MEN 1 syndrome; 4 had MEN 2A syndrome), 40 patients were treated surgically: 29 had initial parathyroidectomy at UCSF; 11 were referred to UCSF because of MEN syndrome. Eight of these 11 patients required reoperation for persistent or recurrent hyperparathyroidism. Patients with hyperplasia were treated with subtotal parathyroidectomy; the glands of those patients with solitary or double adenomas were removed with or without biopsy of the normal appearing glands. RESULTS: Overall, in seven (50%) of 14 patients with hyperplasia, three (16%) of 19 patients with solitary adenoma, and one (14%) of seven patients with double adenomas, recurrent or persistent hyperparathyroidism developed. Failure in patients with hyperplasia was due to missed supernumerary glands (13%) and missed ectopic glands (33%). Failure occurred in patients with solitary (three patients) or double (one patient) parathyroid tumors because of unrecognized hyperplasia. None of the four patient with MEN 2A syndrome had persistent or recurrent disease, but hypoparathyroidism developed in one patient; hypoparathyroidism developed in three patients with MEN 1 syndrome. CONCLUSIONS: These data suggest that although many patients with primary hyperparathyroidism and MEN syndrome have multiple abnormal parathyroid glands, two populations of patients exist; one population has solitary or double adenomas and recurrence is uncommon, whereas the other population of patients has hyperplasia and persistent or recurrent disease is common.

Adenoma↗

PubMedDate not supplied

Meconium ileus and intestinal atresia in fetuses and neonates.

A collaborative study was performed to determine the different types and mechanisms of intestinal abnormalities during gestation. Cases had to fulfill one or more of the following three criteria: (1) meconium ileus, (2) intestinal stenosis or atresia, and (3) meconium peritonitis. Esophageal atresia, anorectal atresia, and abdominal wall defects were excluded. One hundred two cases were reviewed from the autopsies of 42 induced abortions, 22 stillborns, and the surgical findings in 38 neonates. Meconium ileus was detected mainly during the second trimester (28/38), and was associated with cystic fibrosis (15), fetal blood deglutition (4), infection (6), or multiple-abnormalities (10), in which three chromosomal aberrations were found. Intestinal stenosis or atresia was more commonly detected during the third trimester of gestation (46/56). Sixteen of the 30 duodenal malformations were associated with trisomy 21, whereas in the 26 small intestinal atresias, signs of distress or ischemia were most frequently detected. Only 8 of 25 meconium peritonitis cases were isolated. A total of 20 cystic fibrosis cases could be proved. In this series, functional abnormalities were observed predominantly in the second trimester and associated mainly with cystic fibrosis or amniotic fluid abnormalities. Anatomic lesions were commonly detected later on and associated with ischemic conditions, chromosomal aberrations, and even cystic fibrosis.

Constriction, Pathologic↗

PubMed2004

[Diagnostic value of fasting glucose, fructosamine, and glycated haemoglobin HbA(1c) with regard to ADA 1997 and who 1998 criteria for detecting diabetes and other glucose tolerance abnormalities].

New diagnostic criteria for diabetes mellitus proposed by the American Diabetes Association in 1997 and the World Heath Organization Consultation Report in 1998 recommend lowering of the fasting plasma glucose (FPG) to 7.0 mmol/L. This change in the diagnostic FPG cut-off point was based on the results of well-documented epidemiological studies showing that increased risk of microangiopathy starts at values closer to 7.0 than 7.8 mmol/L used in the past. To facilitate the diagnosis, ADA Expert Committee recommends using FPG as the main diagnostic tool and eliminating OGTT from routine clinical practice. In contrast to ADA, WHO Consultation Group strongly recommended keeping OGTT in routine use. Due to the inconvenience, poor reproducibility, non-physiological character and labour-intensiveness of OGTT, an alternative test has been sought. The aim of this study was to determine whether fasting capillary glucose (FCG) along with fructosamine and glycated haemoglobin (HbA(1c)) perform better for the detection of glucose tolerance abnormalities than FCG alone. OGTT was performed in 1528 patients. Serum fructosamine was determined in 480 and glycated haemoglobin in 234 of these patients. To assess the value of FCG, fructosamine and glycated haemoglobin in predicting post-load glycaemia and detecting glucose tolerance abnormalities, multiple linear regression analysis and Receiver Operating Characteristics analysis were done. Fructosamine correlated stronger with 2h-postload glucose concentrations than with fasting glucose. HbA(1c) correlated stronger with FCG than with 2h-postload glucose. Combined use of fructosamine and FCG predicted 2h-postload glucose better than combined use of FCG and HbA(1c). Receiver Operating Characteristics curve analysis showed that FCG was the best criterion in discriminating diabetes. Combined use of FCG and fructosamine slightly improved the ability to discriminate glucose tolerance abnormalities from normal glucose tolerance. The following conclusions were drawn: (1) FCG is the most effective predictor of 2h-postload glucose and the best criterion for discriminating diabetes and other glucose tolerance abnormalities from normal glucose tolerance. (2) Because of the limited sensitivity and specificity of fasting glucose, fructosamine and glycated haemoglobin tests, OGTT is irreplaceable in the identification of patients with glucose tolerance abnormalities. Nevertheless, fructosamine is a potentially useful post-load glycaemia index.

Adult↗

PubMed1993

MR imaging of the tarsal sinus and canal: normal anatomy, pathologic findings, and features of the sinus tarsi syndrome.

After definition of the normal anatomic features of the tarsal sinus and canal at magnetic resonance (MR) imaging, 123 ankle MR imaging studies in 116 patients were reviewed. Abnormalities of the tarsal sinus and canal were seen on MR images in 33 cases (26.8%), were highly associated with tears of the lateral collateral ligament, and could be categorized according to the pathologic findings in patients with sinus tarsi syndrome: (a) diffuse infiltration with low T1- and T2-weighted signal intensity (n = 17) consistent with fibrosis, (b) diffuse infiltration with low T1-weighted signal intensity and increased T2-weighted signal intensity (n = 11) consistent with chronic synovitis and nonspecific inflammatory changes, and (c) multiple abnormal fluid collections (n = 5) consistent with synovial cysts. Absence of the anterior microrecesses of the posterior subtalar joint was a common finding on normal MR imaging studies (46 of 90) and may reflect lack of iatrogenic joint distention. Tears of the posterior tibial tendon may have a previously unrecognized association with the sinus tarsi syndrome.

Adult↗

PubMed2003

[Fetal abnormalities leading to termination of pregnancy: the experience at the Assaf Harofeh Medical Center between the years 1999-2000].

OBJECTIVES: To assess the distribution of fetal indications leading to termination of pregnancy. DESIGN: A retrospective study. METHODS: The study included all parturient women with singleton pregnancy, who underwent termination of pregnancy due to fetal abnormalities (structural, chromosomal/genetic, infections). The women were subdivided into two groups according to their gestational age, i.e. early termination (gestational period < 23 weeks) and late termination (gestational period > 23 weeks). RESULTS: A total of 137 terminations of pregnancies were performed, including 102 early terminations and the rest--late terminations. The mean maternal age was 31 +/- 5 years. The termination procedures were performed at a mean gestational age of 20 +/- 5 weeks. The main indications in the early-termination subgroup were structural and chromosomal/genetic (n = 45, 44% for each subgroup). Multiple abnormalities were more common in the early-termination group (18% versus 7%). In the late-termination subgroup the leading indications were structural anomalies (n = 29, 83%) that were subdivided into neurological defects (31%) followed by skeletal deformities (23%). In addition, in the late-termination subgroup there were more cardiac and urinary tract defects (17% versus 11% and 14% versus 9%, respectively). Among the chromosomal aneuploidies, trisomy 21 was diagnosed in 24 cases (53%). Fetal infections were diagnosed in 13 pregnancies (9%), with only one of these detected in advanced gestation. The leading infectious agent was cytomegalovirus. CONCLUSIONS: In the early-termination subgroup the main indications were equally divided between structural and chromosomal/genetic defects while in the late-termination subgroup the leading cause was structural defects.

Abortion, Induced↗

PubMed1987

The fetus with an abdominal wall defect: management and outcome.

Despite prenatal diagnosis, maternal transport and early perinatal treatment in specialized hospitals, improvement in overall mortality has not been observed among newborns with abdominal wall defects (omphalocele and gastroschisis). A comparison has been made, for both anomalies, between 55 cases treated in the periods 1967-1979 and 30 treated in the periods 1980-1985. In this last group 14 prenatally detected cases were separated from cases discovered at birth. Recent advances in treatment have reduced mortality rates for both of these anomalies. This was especially true for gastroschisis; in omphalocele cases, associated abnormalities appeared to be an unavoidable limiting factor in survival. With prenatal diagnosis a surprising increase in mortality rate was observed among omphalocele cases detected before birth. A possible reason for this is the total number of antenatally diagnosed cases that, with maternal transport, are concentrated in centers where surgical facilities are available. Before introduction of antenatal diagnosis, most of these cases would never have been observed by the pediatric surgeon because of death prior to referral or treatment. Gastroschisis cases may benefit more from antenatal recognition and early treatment because multiple abnormalities or immaturity are not so important limiting factors in survival as in omphalocele cases. Reduced trauma and contamination of exposed viscera, immediate treatment and adequate supportive measures may significantly reduce mortality rate in gastroschisis cases. Operative delivery of fetuses with an abdominal wall defect is controversial. The risk of vaginal route delivery has been over emphasized. Intrapartum rupture of an omphalocelic sac was an extremely rare event before introduction of antenatal diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal Muscles↗

PubMedDate not supplied

Further clinical delineation in trisomy 1q32 syndrome.

A male newborn with multiple congenital abnormalities was studied. Clinically, he showed prominent forehead, facial dysmorphism, ear malformations, congenital heart defect and limb anomalies. The cytogenetic studies demonstrated a karyotype 46,XY, der(18) t(1;18)(q32;p11.3)pat with partial trisomy 1q32-qter and a monosomy 18p. The patient displayed clinical features of trisomy 1q but not of monosomy 18p. There are around 80 reports of trisomy 1q32. The purpose of this paper is to describe the first case of a translocation involving 1q and 18p chromosome breakpoints. Additional findings detected in the propositus permit us a further delineation of the trisomy 1q syndrome.

Abnormalities, Multiple↗

PubMed2004

Tumor-associated endothelial cells with cytogenetic abnormalities.

Tumor angiogenesis is necessary for solid tumor progression and metastasis. Tumor blood vessels have been shown to differ from normal counterparts, for example, by changes in morphology. An important concept in tumor angiogenesis is that tumor endothelial cells are assumed to be genetically normal, although these endothelial cells are structurally and functionally abnormal. However, we hypothesized that given the phenotypic differences between tumor and normal blood vessels, there may be genotypic alterations as well. Mouse endothelial cells were isolated from two different human tumor xenografts, melanoma and liposarcoma, and from two normal endothelial cell counterparts, skin and adipose. Tumor-associated endothelial cells expressed typical endothelial cell markers, such as CD31. They had relatively large, heterogeneous nuclei. Unexpectedly, tumor endothelial cells were cytogenetically abnormal. Fluorescence in situ hybridization (FISH) analysis showed that freshly isolated uncultured tumor endothelial cells were aneuploid and had abnormal multiple centrosomes. The degree of aneuploidy was exacerbated by passage in culture. Multicolor FISH indicated that the structural chromosomal aberrations in tumor endothelial cells were heterogeneous, indicating that the cytogenetic alterations were not clonal. There was no evidence of human tumor-derived chromosomal material in the mouse tumor endothelial cells. In marked contrast, freshly isolated normal skin and adipose endothelial cells were diploid, had normal centrosomes, and remained cytogenetically stable in culture even up to 20 passages. FISH analysis of tumor sections also showed endothelial cell aneuploidy. We conclude that tumor endothelial cells can acquire cytogenetic abnormalities while in the tumor microenvironment.

Aneuploidy↗

PubMed1996

An autosomal dominant, qualitative platelet disorder associated with multimerin deficiency, abnormalities in platelet factor V, thrombospondin, von Willebrand factor, and fibrinogen and an epinephrine aggregation defect.

Multimerin is a massive soluble, multimeric protein found in platelets and endothelial cells. Recent studies identified multimerin as a specific coagulation factor V binding protein, complexed with platelet, but not plasma, factor V. These findings led us to investigate individuals with inherited factor V deficiencies for possible multimerin abnormalities. Platelet proteins were evaluated using immunoassays, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting, immunoprecipitation, and direct binding studies. Patients with factor V Quebec, a disorder with abnormal platelet factor V, had a quantitative deficiency in multimerin (n = 11 tested; mean, 12.5%; range, 5% to 27% of the normal pool; normal range, 45% to 214%) with a normal multimer pattern. Quantitative and qualitative abnormalities were detected in their platelet factor V. An unrelated patient who was deficient in platelet and plasma factor V had normal platelet multimerin. The levels of platelet beta-thromboglobulin, von Willebrand factor, thrombospondin, and fibrinogen antigen were normal in the factor V Quebec patients. However, proteins with abnormal mobility were detected in their platelet lysate and releasate, and their platelet thrombospondin, von Willebrand factor, and fibrinogen showed evidence of proteolytic degradation. Platelet counts of the factor V Quebec patients ranged from mildly thrombocytopenic to low normal (mean, 159 x 10(9)/L; range, 104 to 198 x 10(9)/L). In addition, their platelets failed to aggregate in response to 6 to 10 micromol/L epinephrine despite normal numbers of platelet alpha 2-adrenergic receptors. These data indicate that patients with factor V Quebec have an inherited bleeding disorder distinct from other platelet disorders and associated with multiple abnormalities, including multimerin deficiency, abnormal platelet factor V, thrombospondin, von Willebrand factor, and fibrinogen, and an epinephrine aggregation defect.

Afibrinogenemia↗

PubMed2000

Loss of E2F4 activity leads to abnormal development of multiple cellular lineages.

We have generated mice deficient in E2F4 activity, the major form of E2F in many cell types. Analysis of newborn pups deficient in E2F4 revealed abnormalities in hematopoietic lineage development as well as defects in the development of the gut epithelium. Specifically, we observed a deficiency of various mature hematopoietic cell types together with an increased number of immature cells in several lineages. This was associated with an increased frequency of apoptotic cells. We also found a substantial reduction in the thickness of the gut epithelium that normally gives rise to crypts as well as a reduction in the density of villi. These observations suggest a critical role for E2F4 activity in controlling the maturation of cells in a number of tissues.

Abnormalities, Multiple↗

PubMed1976

Congenital anomalies in children with Wilms' tumor: a new survey.

From 68 hospitals in the National Wilms' Tumor Study, records of 547 patients showed six patients with aniridia, 16 with hemihypertrophy, and 24 with genitourinary abnormalities. Multiple cases of Wilms' tumor occurred in three families. The results confirm high frequencies of aniridia and genitourinary anomalies in patients with Wilms' tumor, and show that concurrence with hemihypertrophy may be more often recognized or recorded now than it was ten years ago. The results demonstrate the desirability of developing checklists for other childhood neoplasms some of which have their own constellation of anomalies.

Child↗

PubMed1996

Epilepsy and brain abnormalities in mice lacking the Otx1 gene.

The morphogenesis of the brain and the differentiation of the neural structures are highly complex processes. A series of temporally and spatially regulated morphogenetic events gives rise to smaller areas that are phylogenetically, functionally and often morphogenetically different. Candidate genes for positional information and differentiation during morphogenesis have been isolated. Both in vivo inactivation in mice and impairment in human diseases revealed, that they are required in regional specification and/or correct cell-type induction. We have previously cloned and characterized the murine Otx1 gene, which is related to orthodenticle (otd), a homeobox-containing gene required for Drosophila head development. Expression data during murine embryogenesis and postnatal brain development support the idea that Otx1 could be required for correct brain and sense organs development. To decipher its role in vivo we produced null mice by replacing Otx1 with the lacZ gene. Otx1-/- mice showed spontaneous epileptic behaviour and multiple abnormalities affecting mainly the telencephalic temporal and perirhinal areas, the hippocampus, the mesencephalon and the cerebellum, as well as the acoustic and visual sense organs. Our findings indicate that the Otx1 gene product is required for proper brain functions.

Animals↗

PubMed1996

Insulin resistance: a multifaceted metabolic syndrome. Insights gained using a low-dose insulin infusion technique.

The term 'insulin resistance', when applied to human disease, is often equated with impaired whole-body insulin-mediated glucose disposal as determined using techniques such as the hyperinsulinaemic glucose 'clamp' technique. Insulin resistance may be defined in more generic terms as 'a state in which normal concentrations of insulin produce an attenuated biological response'--a definition which does not restrict consideration of insulin action to a solitary aspect of metabolism and emphasizes the importance of examining the effects of insulin at concentrations which are relevant to normal physiology. While a number of useful investigative techniques have been developed for the assessment of insulin action in man, most focus narrowly on glucose metabolism; other key aspects of metabolism have received far less attention. Moreover, the pharmacological hyperinsulinaemia usually attained during euglycaemic clamp studies is unsuitable for assessing processes such as adipocyte lipolysis which are maximally inhibited by insulin concentrations within the low-physiological range. In this article we present a summary of our investigations of insulin action in vivo using a low-dose incremental insulin infusion technique. This technique permits examination of circulating insulin/metabolite dose-response relationships within the lower physiological range of plasma insulin concentrations. Using this approach, we have identified multiple abnormalities in the regulation of carbohydrate and lipid metabolism in subjects with a diverse array of insulin-resistant states characterized by variable degrees of glucose intolerance. Of note are the consistent observations of defective regulation of non-esterified fatty acid and glycerol metabolism, being apparent even in patients in whom glucose tolerance was either normal or only marginally impaired. Our studies indicate that defective insulin action is not confined to impaired glucose disposal in insulin-resistant disorders and is usually evident in other aspects of intermediary metabolism. We suggest that the concept of insulin resistance as a pathological entity would be usefully enhanced by greater recognition of the multiple defects in insulin action which may be encountered in insulin-resistant states.

Adult↗

PubMed2004

Osteosarcoma with multiple metastases and subcutaneous involvement in a rabbit (Oryctolagus cuniculus).

BACKGROUND: Osteogenic sarcomas are rare in rabbits, but cases involving the mandible, ribs, frontal bones, and tibia have been reported. OBJECTIVE: The purpose of this study was to describe the clinical and pathologic findings in a rabbit with osteosarcoma and multiple metastases with subcutaneous involvement. METHODS: A 1-year-old female Polish rabbit was evaluated for dysorexia, lameness, gait difficulties with the hind limbs, and the presence of 2 subcutaneous nodules, on the left thigh and in the dorsal region. A hard swelling was also present at the base of the tail. Radiographic findings revealed multiple abnormalities in several bones, which were more severe in the sacrococcygeal region and femur. Several areas of calcification involving the thorax and abdomen as well as skeletal muscles, also were noted. The thigh nodule was surgically removed, and cytologic and histologic evaluations were performed. Following the rabbit's death, postmortem radiographs were taken and necropsy was performed. Samples of tissues and organs, involved bone segments, and other subcutaneous nodules were collected and examined by cytology and histology. RESULTS: Both the subcutaneous nodules and the majority of tissues and organs contained neoplastic cells whose appearance was consistent with osteogenic sarcoma. CONCLUSION: Clinical, radiologic, and pathologic data supported a diagnosis of osteosarcoma with multiple metastases and subcutaneous involvement.

Animals↗

PubMed2004

Chromosome abnormalities identified in 347 spontaneous abortions collected in Japan.

OBJECTIVE: We determined the incidence of specific chromosome abnormalities in this Japanese population so that comparisons could be made to the incidence of chromosome abnormalities reported for other populations. METHODS: A total of 423 cases of products of conception aborted spontaneously were collected for cytogenetics analysis from various medical sites located in Japan. The cytogenetic results, along with clinical information including gestational age at the time of the miscarriage and maternal age, were compiled in a database. The incidence of specific chromosome aberrations was determined. The abnormalities were separated by gestational age at the time of the miscarriage and by maternal age. RESULTS: The total number of specimens available for cytogenetic analysis was 407. Cytogenetic results were obtained for 347 cases (85.3%), of which 196 (56.5%) showed chromosome abnormalities. Autosomal trisomy was detected in 120 cases (61.2% of the abnormal cases). Trisomy for each autosome, with the exception of chromosomes 1, 5, 6, 11, 12, and 19, was identified. The most common autosomal trisomy was that of chromosome 16 (30 cases), followed by trisomy 21 (13 cases), and trisomy 22 (13 cases). Eight cases showed double trisomies, and one case showed trisomy for three different chromosomes. Two cases showed monosomy 21, and 24 cases showed 45,X. Triploidy was identified in 27 cases and tetraploidy was detected in five cases. Unbalanced structural rearrangements were found in 11 cases, and balanced translocations were identified in two cases. Six cases showed mosaicism: three cases showed a normal cell line; and three cases had multiple abnormal cell lines. Separating the trisomies by the gestational age at which time the miscarriage occurred revealed that trisomies 7, 8, 14, 15, 16 and 22 occurred exclusively during the first trimester and fetuses with trisomies 4, 13, 18 and 21 survived late into the second trimester. CONCLUSION: Overall patterns of chromosome abnormalities detected in spontaneous abortions in Japan were similar to those reported in the literature.

Abortion, Spontaneous↗

PubMed2006

Increased susceptibility to maternal aneuploidy demonstrated by comparative genomic hybridization analysis of human MII oocytes and first polar bodies.

Single cell comparative genomic hybridization (CGH) was employed to extensively investigate 24 unfertilized or in vitromatured meiosis II oocytes and their corresponding first polar bodies (PBs), to determine how and whether all 23 chromosomes participate in female meiosis I errors and to accurately estimate the aneuploidy rate in the examined cells. Results were obtained for 15 oocytes and 16 PBs, representing 23 eggs (MII oocyte-PB complexes) donated from 15 patients (average age 32.2 years). Abnormalities were detected in ten eggs, giving an overall aneuploidy rate of 43.5%. In all, fourteen anomalies were scored, with the fertilized oocyte being at risk of monosomy in eight cases and at risk of trisomy in six; chromosomes of various sizes participated. CGH was able to give a comprehensive aneuploidy rate, as both absence of chromosomal material and the presence of extra copies were accurately scored. The aneuploidy mechanisms determined were: classical whole univalent non-disjunction; chromatid predivision prior to anaphase I, leading to metaphase II imbalance. There was also evidence of germinal mosaicism for a trisomic cell line. Three patients appeared to be predisposed to meiosis I errors, based on the presence of either multiple abnormalities in one or more of their examined cells, or of the same type of abnormality in all of their cells. Exclusion of these susceptible patients reduces the aneuploidy rate to 20%. Various hypotheses are put forward to explain these observations in order to stimulate research into the complex nature of female meiotic regulation.

Adult↗