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31.
Monosomy 9q and trisomy 16q in a case of congenital solitary infantile myofibromatosis 总被引:1,自引:0,他引:1
Sirvent N Perrin C Lacour JP Maire G Attias R Pedeutour F 《Virchows Archiv : an international journal of pathology》2004,445(5):537-540
Although infantile myofibromatosis (IM) is the most common fibrous proliferation of infancy, many aspects of this benign lesion have not been explored. IM histogenesis is still poorly understood, despite immunohistochemical staining and ultrastructural features that suggest a myofibroblastic origin. IM diagnosis is often made difficult by the predominance of small primitive spindle cells over myofibrobasts and the presence of intravascular growth. Genetic information is scarce, with only one karyotyped case. Here we describe a case of solitary IM discovered at birth in an otherwise healthy girl. The tumor was well circumscribed, arranged in nodules and made up of ovoid cells without atypia, in a myxoid background. Immunohistochemical evaluation indicated a myofibroblastic differentiation. The cytogenetic and fluorescence in situ hybridization analyses revealed an abnormal chromosome 9, derived from an unbalanced whole-arm translocation between chromosomes 9 and 16. On both chromosomes, the breakpoints were located in the pericentric heterochromatic region. This clonal abnormality has not been reported in other tumors and is different from the chromosome 6q deletion reported in the single previous reported IM karyotype. 相似文献
32.
33.
The distribution and metabolism of ACTH and the dynamics of the adrenal cortical response to this tropic hormone were characterized
in the rat, through mathematical models involving data derived from experiments, where plasma corticosterone concentrations
were measured following both single injections and infusions of ACTH. The models, which incorporate a previously established
model of the dynamics of plasma corticosterone, were statistically validated. The simulated dynamics of the different processes
linking ACTH secretion by the adenohypophysis to corticosterone secretion by the adrenal cortex include: (1) a variable MCR
for plasma ACTH, modeled as the sum of a constant and a saturable degradation process; (2) the ability of the adrenal gland
to secrete at a maximal rate aven after the plasma ACTH concentration has become negligible, modeled as the accumulation of
an intermediary productZ directly controlled by the plasma ACTH concentration; (3) a saturable secretion with a small time constant and which, for
single injections, always starts in the same fashion, modeled as a “synthesis process” whose input is a saturable function
ofZ; (4) an immediate fall of the plasma corticosterone concentration at the end of the ACTH infusions, modeled as a “release
process” also controlled byZ.
Supported by grants from the Medical Research Council of Canada (MT-1205, MT-1555, and MA-4970), and from INSERM, France (CRL-76-5-020-4). 相似文献
34.
A. Al Saadi Joseph F. Juliar John Harm A. Joseph Brough Eugene v. Perrin Harold Chen 《Clinical genetics》1976,9(1):43-50
Two live-born cases, 69,XXY and one stillbirth, 69,XXX are reported. Further evidence is presented to delineate the triploidy syndrome. Common external and internal features which characterize the triploidy syndrome are low-set ears, hypertelorism, colobomata, syndactyly, simian creases, microphallus, undescended testes, scrotal aplasia, anomalous heart and hypoplasia of kidneys and adrenals. The triploidy syndrome encompasses features found in trisomies 13, 18 and 21. We suggest that the abnormal development of the triploidy infants is the result of the mentioned trisomies and their subsequent effect on the remaining genome. 相似文献
35.
Irving Dardick Sharon Cavell David Moher Peggy Seely Alexander Dardick Marilyn McDougall Bruce F. Burns 《Ultrastructural pathology》1989,13(4):393-404
Ultrastructural morphometric analysis was carried out on six cases of lymph node biopsies with reactive hyperplasia to establish the frequency and depth of invaginations in nuclear profiles situated in the mantle zones and follicular centers. The frequency distribution of the depth of invaginations was similar in nuclear profiles whether in the small lymphocytes of mantle zones or the small, partially transformed (centrocytes) and fully transformed (centroblasts) lymphocytes of follicular centers. Invaginated and cleaved lymphocytes were not confined to the partially transformed (centrocytic) lymphocytes of follicular centers, and nuclear profiles with invaginations bore no resemblance to those depicted in the Lukes-Collins model. A considerable proportion of mantle zone lymphocyte nuclear profiles had invaginations (ranging from 7.5% to 53.6%) and there was no difference between the frequency of deep indentations or clefts in mantle zone lymphocytes (8.1 ± 5.4%) and the small unstimulated (9.3 ± 5.3%) and partially transformed (8.4 ± 1.4%) lymphocytes in follicular centers. Computer modeling of stylized nuclei with conical indentations indicated that all lymphocytic nuclei likely have multiple invaginations or groove-like creases. 相似文献
36.
Perrin A Bauza E Dal Farra C Domloge N 《International journal of tissue reactions》2004,26(3-4):97-104
Recent studies of our newly developed synthetic collagen-like hexapeptide have shown that it enhances cultured cell adhesion and differentiation and improves the morphology of ex vivo skin. Consequently, we were interested in further investigating the effects of the collagen-like peptide on the skin. We performed different immunostaining studies on ex vivo human skin samples treated with the collagen-like peptide at 1% in time course studies. Our research also included comparative studies with vitamin C (often used as a positive control for enhancing collagen synthesis). The results showed that application of the collagen-like peptide to the skin enhanced synthesis of many extracellular matrix (ECM) molecules and that this effect was observed very early in some ECM molecules such as laminin 5, collagen 111, and collagen IV The expression of the other molecules was increased after different times of application of the collagen-like peptide. Interestingly, comparative studies with vitamin C showed that the synthesis response of some ECM molecules such as laminin 5, collagen 111 and collagen IV was more rapid after the administration of the collagen-like peptide than through vitamin C administration. Our results also revealed that after a longer treatment period, both active ingredients stimulated ECM molecule synthesis to a similar degree, with the exception of some molecules that remained superiorafterpeptide administration, such as collagen IV and beta 1 integrin. These histological studies demonstrate the remarkable and rapid effect of the collagen-like peptide on stimulating ECM molecule synthesis and suggest wide application for the peptide in antiaging and photoaging skin care products. 相似文献
37.
BACKGROUND: Pathological gambling is more prevalent among postsecondary students than among the general adult population. While the prevalence of pathological gambling in this group has risen over the past decade, factors underlying the development of problem gambling among university students remain largely unexplored. One early study found alexithymia to be associated with pathological gambling. The aim of the present study was to further examine the relationship between alexithymia and gambling among postsecondary students. METHODS: The relationship between alexithymia and pathological gambling was examined in 562 postsecondary students who completed the South Oaks Gambling Screen (SOGS) and the 20-item Toronto Alexithymia Scale (TAS-20). RESULTS: Approximately 12% of the sample was classified as alexithymic according to the TAS-20. These individuals were found to have significantly more gambling problems, as measured by the SOGS, than nonalexithymic individuals. Approximately 9% of the sample was classified as pathological gamblers according to the SOGS. These individuals were found to have significantly higher levels of alexithymia, as measured by the TAS-20, than nonproblem gamblers. CONCLUSIONS: Alexithymia is associated with pathological gambling and may be a risk factor among postsecondary students for developing severe gambling problems. 相似文献
38.
Partha Biswas Govindsamy Kumaramanickavel Corinne Stoetzel Renaud Quillet Jyotirmay Biswas Elisabeth Lajeunie Dominique Renier Fabienne Perrin‐Schmitt 《American journal of medical genetics. Part A》2002,109(3):218-225
Saethre‐Chotzen syndrome is an autosomal dominant disease characterized by craniosynostosis, ptosis, and limb and external ear abnormalities. Variable expressivity is a well‐known phenomenon in this disorder. A large Indian family has been recently identified as carrying a nonsense TWIST mutation (Q28 X) in 17 members, of whom 16 were examined in detail. Only 4 (25%) of the patients showed patent craniostenosis, namely, oxycephaly. The penetrance of craniosynostosis in this family is lower than previously reported in the literature. Fifteen patients (93%) had moderate to severe ptosis. Minor limb and external ear abnormalities were present in most patients. Eyelid features were the hallmark of the disease for 12 members of the family, suggesting that mutations in TWIST may lead to a phenotype with mainly palpebral features and no craniostenosis. The clinical analysis of this large family clearly illustrates the significant variable expressivity, probably related to haploinsufficiency because of the TWIST mutation. This phenotypic variability remains unclear but could be the result of modifier genes and/or genetic background effect, as noticed previously in the transgenic twist‐null heterozygous mice. © 2002 Wiley‐Liss, Inc. 相似文献
39.
Ageing is associated with a decrease in the quality of balance regulation, in particular through dysfunctions of gaze control and postural stabilization, which results in an increased risk of falling. Conversely, the practice of physical and sporting activities has been shown to improve every level of postural regulation. This study is to assess the effects of the practice of physical activities on vestibulospinal reflex and ocular movements of visual and vestibular origins in elderly people. Gaze control and posture stabilization were evaluated in 13 healthy aged women who regularly practised physical activities and in 13 healthy aged sedentary women of a similar age, by dynamic posturographic test with electromyography, as well as electronystagmography with caloric and rotational vestibular tests, ocular saccades, smooth pursuit and optokinetic tests. The gaze and posture control performance of the active group was better; the proprioceptive and vestibular sensitivities were higher, visual detection quality was good, and reaction time was low. Regular physical activity develops or maintains the efficiency of the reflexes involved in postural control, especially through adequate neurosensorial information, which allows the central integrative structures to generate a more appropriate motor response. 相似文献
40.
Journal of Public Health - The purpose of this editorial is to provide guidance for the readers concerning the broad realm of approaches towards successful implementation of digital health... 相似文献