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41.
A diagnosis of the Neu-Laxova syndrome (NLS) was made by ultrasonography at 32 wks of gestation. Ultrasonographic examination showed intrauterine growth retardation (IUGR), Dandy-Walker anomaly, choroid plexus cysts, receding forehead and microcephaly, bilateral cataract without prominent eyes, scalp edema with no generalized edema, retrognathia, curved penis, and flexion deformities of limbs. The findings in this case are consistent with NLS; however, they did not fit any of Curry's [1982] groups. Massive swelling of hands and feet were among the main manifestations in classic NLS cases. In the case presented herein, edema was noted only in the scalp. This might shed further light on the question of variability vs. heterogeneity in the NLS. This case shows the existing possibility of an early diagnosis of NLS and adds Dandy-Walker anomaly and choroid plexus cysts as new findings to this syndrome. © 1992 Wiley-Liss, Inc.  相似文献   
42.
The association of rheumatoid arthritis (RA) with particular MHC class II genes suggests that autoantigen-spccific T cell clones present in joints could be central to the pathogenesis of the disease. Previous investigations on the clonal diversity of T cells infiltrating the rheumatoid synovial membrane have yielded conflicting results. With the use of Southern blot analysis, we investigated the clonalily of rheumatoid T cell lines expanded from peripheral blood, synovial fluid and synovial tissue. From peripheral blood lymphocyte (PBL) of RA patients and healthy normal controls, we also checked the consequences of two different culture conditions on the clonality of these cell lines. From control PBL, we found that in vitro non-specific expansion of non-clonal T cell populations does not create artefactual clonal selection. However, growing T cells in ritro with IL-2 seems to be able to lead to preferential expansion of cells bearing IL-2 receptor (IL-2R). We identified such in vivo activated IL-2-sensitive T cell clones frequently in RA synovial tissue (8/13) and more rarely in synovial fluid and peripheral blood (3/12). One patient presents the same T cell receptor gene rearrangements in synovial membrane of two affected joints. In RA synovial tissue, the frequency of these IL-2-responsive T cells is most prevalent among actively inflamed membranes removed early in the disease process. The role and the relevance to the disease of these I L-2-responsivc T cells remain to be elucidated.  相似文献   
43.
Heterogeneity of pseudoxanthoma elasticum: delineation of a new form?   总被引:2,自引:0,他引:2  
Sixty-four patients with pseudoxanthoma elasticum (PXE) were investigated in a nationwide study within South Africa and Zimbabwe. Thirty-nine individuals formed a distinct clinical subgroup. These persons were found exclusively among people of Afrikaner descent, whose origins are mainly derived from Dutch and French-Huguenot stock. This disorder was inherited as an autosomal recessive trait and presented mild to moderate cutaneous and cardiovascular manifestations. However, after the third decade of life severe visual impairment developed and culminated in blindness in 8 people by the age of 50. The cause of the visual defect was progressive extension of angioid streaks into the macula with neovascularization and haemorrhage. Laser therapy may have prevented further bleeding in 4 instances. The severity of ocular involvement contrasted with the mildness of the skin changes, and in this respect the condition seems to differ from previously delineated autosomal recessive forms of PXE.  相似文献   
44.
Cranial sclerosis with osteopathia striata was diagnosed in four members of a family in three generations. The expression of the gene varied from mild cranial enlargement to cranial abnormality associated with severe Pierre-Robin triad. The disorder was diagnosed prenatally in the most severely affected member of the family from the finding of an increased biparietal diameter of the fetal head on ultrasound examination.  相似文献   
45.
 Hereditary spastic paraplegia (HSP) is a group of clinically and genetically heterogeneous neurodegenerative disorders characterized by slowly progressive spasticity and weakness of the lower extremities. Among eight loci linked with autosomal-dominant (AD)-HSP, the SPG4 locus on chromosome 2p22 accounts for about 40% of all patients. Recently, mutations in a new member of the AAA protein family, called spastin, have been identified as responsible for SPG4-linked AD-HSP. Here, we describe a novel missense mutation (c.1031T>A; I344K) in exon 7 of the SPG4 gene identified in a Korean family with typical clinical features of pure AD-HSP. The mutation affects the third amino acid of the highly conserved AAA cassette domain, which is the most fore part of the domain altered by a missense mutation reported so far. Clinical presentations of affected individuals carrying the I344K mutation were not different from those of pure AD-HSP with SPG4 mutations reported previously. However, it is noteworthy that neither urinary dysfunction nor involvement of upper extremities was noticed in this family. To our knowledge, this is the first report of genetically confirmed AD-HSP in Korea. Received: February 20, 2002 / Accepted: May 21, 2002  相似文献   
46.
Purine nucleoside phosphorylase (PNP) deficiency results in an autosomal recessive immunodeficiency disease characterized by initial involvement of cellular immunity and neurological manifestations with subsequent abnormalities of humoral immunity. The initial presentation and clinical course has varied widely in the relatively few published cases. The molecular basis has been reported in only 10 patients, precluding evaluation of phenotype-genotype relationships. We now report clinical, immunologic, and molecular findings in a new case of relatively early onset that emphasizes hypotonia and developmental delay as early manifestations. The patient carried two novel missense mutations (Gly56A1a and Val217Ile) on the same allele in apparent homozygosity. Expression of each of the mutant enzymes in vitro demonstrated that the Gly156A1a mutation abolished enzyme activity while the Val217Ile mutation was without obvious effect and is therefore a normal variant. Such "normal" polymorphisms might be associated with a variable response to the immunosuppressive PNP inhibitors currently in clinical trials.  相似文献   
47.
48.
We report three novel activating mutations in the calcium-sensing receptor (CASR) that are responsible for autosomal dominant hypocalcemia (ADH) in three unrelated families. Each mutation involves a missense substitution resulting in a nonconservative amino acid alteration, P221L, E228Q, and Q245R. These mutations were observed in affected family members, but not in unaffected family members or in unrelated control samples. All three mutations are clustered in the extracellular domain of the CASR in a region dominated by negatively charged amino acids. Each mutant and wild-type receptor was expressed in Cos-1 cells. A luciferase reporter gene assay was utilized to detect the level of receptor activity by utilizing a protein kinase C-activated promoter to drive the production of luciferin, the reporter gene product. All three mutant receptors exhibited an increased sensitivity to calcium at all concentrations tested when compared to the wild-type receptor, supporting the hypothesis that these are activating mutations and are responsible for the ADH phenotype in these families. The data presented in this study suggest the importance of this highly negatively charged region of the extracellular domain in normal CASR function.  相似文献   
49.
Urticaria in response to various physical stimuli has been reported in sporadic and familial patterns. The most common of these physical urticarias, dermographism, is a localized urticarial response to stroking or scratching of the skin and has not been reported previously to be familial. A four-generation family with dermographism, probably inherited as an autosomal dominant trait, is presented along with a discussion of sporadic dermographism and other types of familial physical urticarias.  相似文献   
50.
Wiedemann‐Steiner syndrome (WSS) is a rare genetic disorder characterized by growth retardation, facial dysmorphism, hypertrichosis cubiti and neurodevelopment delay. It is caused by pathogenic variants in the KMT2A gene. This report describes two unrelated Portuguese patients, age 11 and 17 years, with a phenotype concordant with WSS and clinical and molecular diagnosis of WSS by the identification of two novel frameshift variants in the KMT2A gene. This work also highlights the presence of certain clinical features in patients with growth retardation and development delay and should draw attention to the diagnosis of WSS, when hirsutism, particularly hypertrichosis cubiti is present.  相似文献   
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