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91.
Teshima I Bawle EV Weksberg R Shuman C Van Dyke DL Schwartz S 《American journal of medical genetics》2000,94(2):113-119
Two cases of marker chromosomes derived from a non-centromeric location were studied to determine the characteristics of these markers with respect to the presence of functional centromeres and whether an associated phenotype could be described. The markers were characterized by fluorescence in situ hybridization and centromeric protein studies. Assessments were done to identify clinical features. Case 1 is a girl referred at age 1.5 years with swirly areas of hyperpigmentation, bilateral preauricular pits, hypotonia, developmental delay, and seizures. Case 2 is a male first evaluated as a newborn and then later during the first year of life. He had streaky hypopigmentation, right preauricular pit, accessory nipples, postaxial polydactyly, asymmetric cerebral ventricles, duplicated right kidney, a right pulmonary artery stenosis, and seizures. Mosaicism for an extra marker from the 3qter region was present in both cases. Both markers had a constriction near one end and were C-band negative. Centromeric protein studies indicated absence of CENP-B, presence of CENP-C (data for case 1 only), and presence of CENP-E. Marker chromosomes were thus identified with a chromosomal origin far from their usual centromeric region and yet appeared to have functional centromeres. These two cases did not permit a specific clinical phenotype to be ascribed to the presence of tetrasomy for 3q26.2 approximately 3q27.2-->3qter. 相似文献
92.
Matsuo T Wanaka K Asada R 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(7):622-629
Heparin-induced thrombocytopenia(HIT) due to immunological mechanisms is known as an important adverse reaction to heparin treatment, and heparin treatment should be applied while keeping in mind the risk of onset of HIT 5-14 days after the initiation of heparin. The presence of HIT had not been fully recognized in clinical practice in Japan despite the management of HIT being well confirmed in Western countries. Recognition of HIT has increased since argatroban, a direct thrombin inhibitor, obtained the approval of the FDA for prevention and treatment of HIT. Although the incidence of HIT in Japan has not yet been clarified, there is some evidence that HIT is encountered in critically ill patients undergoing heparin anticoagulation. Clinical diagnosis of HIT is performed by means of thrombocytopenia of a drop of 50% or 100 x 10(30/microl for 5 -14 days after starting heparin treatment. Confirmatory laboratory tests examine whether the patients have antibodies against heparin/PF4 complexes or not. Two assay tests for detecting heparin/PF4 complex antibodies are available in Japan. As a functional test, the heparin-induced platelet aggregation method is easily performed and the result is obtained in a short time. The result of the test has, however, been misleading due to the selection of donors. Low platelet activity of the donors on the addition of heparin induces a negative response in spite of positive antibodies in the sample. Before testing samples, it is important to check heparin reactivity of the donor's platelets. Enzyme immunoassay detecting the antibodies is available as a commercial kit. Sensitivity obtained by enzyme immunoassay is very high and often introduces false-positives. Careful attention to interpretation of the result is required. Treatment of HIT should be started at the time of recognition of thrombocytopenia while antibody testing for HIT is performed. As an alternative anticoagulant to heparin, argatroban should immediately be applied to avoid complication of thrombosis. Thrombocytopenia and hypercoagulability quickly recover to the preheparin level by the appropriate use of argatroban. 相似文献
93.
Saheki T Kobayashi K Iijima M Horiuchi M Begum L Jalil MA Li MX Lu YB Ushikai M Tabata A Moriyama M Hsiao KJ Yang Y 《Molecular genetics and metabolism》2004,81(Z1):S20-S26
Citrin is a mitochondrial aspartate glutamate carrier primarily expressed in the liver, heart, and kidney. We found that adult-onset type II citrullinemia is caused by mutations in the SLC25A13 gene that encodes for citrin. In this report, we describe the frequency of SLC25A13 mutations, the roles of citrin as a member of the urea cycle and as a member of the malate-aspartate shuttle, the relationship between its functions and symptoms of citrin deficiency, and therapeutic issues. 相似文献
94.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Kazuno Imai Yoshikazu Kandori Akira Ishizuka Atsushi Osada 《European journal of applied physiology》1993,67(4):354-359
Summary We have examined the nonparallel changes in tampanic membrane temperatures (T
ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T
ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T
ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T
ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T
ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T
ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T
ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation. 相似文献
95.
Keiko Murayama Robert S. Greenwood Kathleen W. Rao Arthur S. Aylsworth 《American journal of medical genetics. Part A》1991,40(4):488-492
We have studied three children with de novo terminal deletion of the long arm of chromosome 1 (46,XX,del(1)(q43)). They all have minor anomalies and neurological signs (severe psychomotor developmental delay, generalized hypotonia, and seizures) that have been described previously. In addition, all of these three patients have autistic-like behavior. They avoid eye contact, show no interest in people, express little emotion, and repeat stereotypic movements such as head nodding and purposeless finger manipulation. They also spend excessive time in making unusual sounds consisting of a high-pitched shrill cry with little intonation in infancy and a harsh, strained, and glottal stridency in later life. They make no labial, lingual, or nasal sounds. We suggest that these observations may be unique clinical manifestations of certain terminal 1q deletions. 相似文献
96.
Syun Hosoda Harumi Suzuki Takeshi Oguri Keiko Ikuta Toshiharu Nagatsu 《Pathology international》1976,26(4):519-531
A case of adrenal pheochromocytoma Is reported characterized by polygonal basophilic granular cells of benign type, plump eosinophilic granular cells of transitional type, and spindle-shaped cells of malignant type. In the primary tumor the neoplastic cells of each type revealed a distinctive topographical distribution. All gradations between the latter two varieties of cells were found, especially in the vicinity of the transitional cell area. Multiple metastases were present in the liver and lungs, where only anaplastic spindle-shaped cells could be found. Ultrastructurally, the benign cells contained predominantly large, rather light, secretory granules with a coarsely granulated core. In the malignant cells, the number, size, and intensity of granules varied considerably from cell to cell or even within a single cell. In general, the malignant cells had a higher frequency of smaller granules with electron-dense homogeneous cores. Moderate amounts of noradrenalin but not significant dopamine or adrenalin could be demonstrated from a metastatic nodule In liver. We postulate that this adrenal medullary pheochromocytoma was benign originally and underwent malignant transformation shortly before the patient's death. This is based upon the patient's clinical features and the peculiar structures of the primary tumor. 相似文献
97.
Kiyoshi Tanikawa Takamichi Enomoto Masahiro Hatano Keiko Motegi Zenjiro Okuno 《Macromolecular chemistry and physics.》1975,176(10):3025-3034
Poly(N-vinylcarbazole), (PNVC), was prepared, fractionated by gel permeation chromatography, and then characterized by viscometry and vapour pressure osmometry. The fractionated PNVC species with relatively narrow molecular weight distributions were successfully used to measure both their electrical dark-conductivity and photoconductivity using a surface type cell in high vacuum (ca. 10?7 mm Hg) at room temperature. A molecular weight dependent photoconductivity was found for the fractionated PNVCs with weight average molecular weights in the range of 1,2·103 to 2,4·105. This observation is in contradiction to Epping's results who has found a molecular weight independent photoconductivity in the molecular weight range of 3·105 to 7·106. Our molecular weight dependence may be well understood in terms of the interrupted overlap of the π-electrons of adjacent carbazolyl groups at the terminal parts of the polymer chains, this effect being all the more stronger the smaller the molecular weight is. 相似文献
98.
Velo-cardio-facial syndrome: Implications of microdeletion 22q11 for schizophrenia and mood disorders 总被引:2,自引:0,他引:2
Arnold PD Siegel-Bartelt J Cytrynbaum C Teshima I Schachar R 《American journal of medical genetics》2001,105(4):354-362
Velo-cardio-facial syndrome (VCFS) is a congenital malformation syndrome with variable phenotypic features that has been associated with chromosomal microdeletion 22q11.2. Psychiatric disorders have been reported to be highly prevalent in individuals with this syndrome, and the objective of this study was to assess the nature and extent of psychopathology among individuals with VCFS. We studied 20 children and adolescents with 22q11 deletions determined by fluorescence in situ hybridization (FISH). Control subjects were 11 nondeleted siblings who were the closest age match to the affected subjects. Both affected and control subjects were assessed using two standardized psychiatric research instruments. The results of this study confirmed the high rate of psychiatric disorders among VCFS subjects (60% of our subjects). Of the specific types of disorders, only mood disorders were significantly more common among VCFS subjects compared to sibling controls, with eight VCFS subjects having mood disorders compared with none of the control subjects (P<0.02). Three affected subjects had schizotypal traits comorbid with a mood disorder. In addition, disruptive behavior disorders were frequently diagnosed among VCFS subjects. Using a dimensional measure of psychopathology, significant differences between VCFS subjects and sibling controls were found on three scales: ADHD (P<0.02), separation anxiety (P<0.02), and depression (P<0.01). VCFS subjects were achieving significantly less well academically and requiring significantly more special educational assistance than sibling controls. Follow-up data were available on two subjects, both of whom had been diagnosed with schizophrenia. Further research on psychopathology in VCFS may provide a model of how a specific genetic defect can lead to the development of psychiatric disorders. 相似文献
99.
The purpose of the present study was to understand the concept of aggressiveness of children through an analysis of the relationship between aggressiveness and personality traits. A total of 1,206 elementary school children were enrolled in the study. In order to investigate the correlation, a path analysis was performed using multiple regression analyses in which 4 variables of aggressiveness (irritability, hostility, physical aggression and verbal aggression) were employed as dependent variables and 5 variables of personality traits (agreeableness, conscientiousness, emotionality, openness and extroversion) were used as independent variables. The results of the analysis indicated that significantly positivepath was observed from extroversion to all four variables of aggressiveness. Extroversion indicated especially strong influence on irritability and physical aggression. A significantly negativepath was observed from agreeableness to irritability and hostility. From conscientiousness, a negative path was observed towards physical aggression and a positive path towards verbal aggression. A significantly negative path was observed from emotionality only towards verbal aggression. It was assumed that each of the four inferior characteristics of aggressiveness of children had a complex nature to be influenced by multiple personality traits. 相似文献
100.
Yasunori Higuchi Yoichi Tamura Tomohisa Uchida Keiko Matsuura Naoki Hijiya Shunsuke Yamamoto 《Pathobiology》2004,71(1):1-11
We generated transgenic mice expressing osteopontin (OPN) under the control of the alpha(1)-antitrypsin promoter. These mice (OPN-T mice) expressed OPN mRNA in liver and kidney, and released a large amount of plasma OPN, which increased after stimulation with turpentine oil. Before sensitization, the number of CD4+ T cells in lymph nodes was significantly higher in OPN-T than nontransgenic mice, and that in spleen was slightly higher, whereas that of CD8+ T cells was no different between OPN-T and nontransgenic mice. After sensitization, the CD4+ T cell numbers in spleen increased significantly, while there were almost no changes in the CD8+ T cells in lymph nodes and spleen. The intensity of contact hypersensitivity responses to 2,4-dinitrofluorobenzene (DNFB) was obviously enhanced in OPN-T mice. In the delayed-type hypersensitivity (DTH) model elicited by DNFB, the number of CD8+ T cells among DNFB-2,4,6-trinitrobenzenesulfonic acid (TNBS)-peritoneal exudate cells was significantly higher in OPN-T than nontransgenic mice, while there was almost no difference in that of CD4+ T cells. Adoptive transfer experiments revealed that the enhanced reactivity is carried by CD4+ and CD8+ T cells, respectively, although the ability of transferring DTH was significantly lower in CD8+ than in CD4+ T cells. The enhancement of CD8+ T cell migration was observed in OPN-T mice. These results suggest that OPN induces a proliferation of effector CD4+ and CD8+ cells in cell-mediated reactions and plays a role in the migration of CD8+ T cells. 相似文献