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141.
Rybicki  AC; Qiu  JJ; Musto  S; Rosen  NL; Nagel  RL; Schwartz  RS 《Blood》1993,81(8):2155-2165
Red blood cell (RBC) protein 4.2 deficiency is often associated with a moderate nonimmune hemolytic anemia, splenomegaly, and osmotically fragile RBCs resembling, but not identical to, hereditary spherocytosis (HS). In the Japanese type of protein 4.2 deficiency (protein 4.2Nippon), the anemia is associated with a point mutation in the protein 4.2 cDNA. In this report, we describe a patient with moderate and apparently episodic nonimmune hemolytic anemia with splenomegaly, spherocytosis, osmotically fragile RBCs, reduced whole cell deformability, and abnormally dense cells. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis analysis of the proposita's RBC membrane proteins showed an 88% deficiency of protein 4.2 and a 30% deficiency of glyceraldehyde-3-phosphate dehydrogenase (band 6). Structural and molecular analyses of the proposita's protein 4.2 were normal. In contrast, limited tryptic digestion of the proposita's band 3 showed a homozygous abnormality in the cytoplasmic domain. Analysis of the pedigree disclosed six members who were heterozygotes for the band 3 structural abnormality and one member who was a normal homozygote. Direct sequence analysis of the abnormal band 3 tryptic peptide suggested that the structural abnormality resided at or near residue 40. Sequence analysis of the proposita's band 3 cDNA showed a 232G-->A mutation resulting in a 40glutamic acid-->lysine substitution (band 3Montefiore). Allele-specific oligonucleotide hybridization was used to probe for the mutation in the pedigree, showing that the proposita was homozygous, and the pedigree members who were heterozygous for the band 3 structural abnormality were also heterozygous for the band 3Montefiore mutation. The band 3Montefiore mutation was absent in 26 chromosomes from race-matched controls and in one pedigree member who did not express the band 3 structural abnormality. In coincidence with splenectomy, the proposita's anemia was largely corrected along with the disappearance of most spherocytes and considerable improvements of RBC osmotic fragility, whole cell deformability, and cell density. We conclude that this hereditary hemolytic anemia is associated with the homozygous state for band 3Montefiore (40glutamic acid-->lysine) and a decreased RBC membrane content of protein 4.2. We speculate that band 3 structural abnormalities can result in defective interactions with protein 4.2 and band 6, and in particular, that the region of band 3 containing 40glutamic acid is involved directly or indirectly in interactions with these proteins.  相似文献   
142.
Oculocutaneous albinism   总被引:2,自引:0,他引:2  
Oculocutaneous albinism represents a group of inherited skin disorders characterized by a generalized reduction of cutaneous, ocular and pilar pigmentation from the time of birth. Oculocutaneous albinism types 1 and 2 are the most common, but several other types have been described. A defect in the melanin synthesis pathway, resulting in reduced formation of melanin, is responsible for oculocutaneous albinism. Aetiology, clinical manifestations, diagnosis and management are discussed.  相似文献   
143.
A woman with a 5-year history of unilateral orofacial granulomatosis required repeated evaluations (including sequential colonoscopies) to establish the diagnosis of cutaneous Crohn's disease, a condition that proved responsive to low doses of oral methotrexate administered weekly. To our knowledge this is the first report describing the use of methotrexate for treatment of orofacial granulomatosis caused by underlying Crohn's disease.  相似文献   
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Lymphadenopathy is the commonest presentation in HIV positive individuals. Fine needle aspiration cytology of 196 HIV positive patients was studied during six monthly review. 75% paients in this study who were asymptomatic were detected to have lymphadenopathy during the surveillance. 82% had lymph nodes smaller than 1cm size. Lymphadenopathy at more than one site was observed in 46.8% cases. Commonest opportunistic infection noticed was tuberculosis (TB) in 34.2%. Cyto-morphologically reactive pattern with Add fast bacilli (AFB) positivity was observed in 16.4% of TB cases. In 2.9% cases AFB were detected even in the tissue fluid. Negative images of AFB were observed in the macrophages in 3 cases. TB was detected with equal frequency in both asymptomatic and symptomatic groups. Axillary nodes pose problem due to deeper location. False positives were a case of dermatopathic lymphadenopathy and a case of Kimura''s disease. False negatives include two cases of TB lymphadenitis. Pathogens should be looked for irrespective of cyto-morphology. Biopsy should be done to confirm cases of lymphomas. Fine needle aspiration cytology should be included in the protocol of six monthly review of HIV infected cases.KEY WORDS: AIDS, FNAC, HIV, Lymph node, Tuberculosis  相似文献   
148.
In mice, whiskers on the snout form a highly specialized tactile organ with exquisitely patterned neural representations in the brain. Targeted deletion of the Msx2 gene leads to severe craniofacial defects, and stubby, curly whiskers. We examined the whisker pad histology, innervation, and whisker-related pattern formation along the trigeminal pathway in Msx2 -/- mice. Although the whiskers are severely deformed, whisker follicle structure, pattern and density of innervation, as well as central neural patterns in the brainstem, thalamus, and cortex appeared normal. We conclude that whisker-related neural patterns can form in the absence of normal whiskers, as long as whisker follicle innervation is intact.  相似文献   
149.
Naevus of Ota is a dermal melanocytosis most commonly found in black or Asian skin and is usually a benign malformation, but with a low risk of melanoma. We describe a 32-year-old Caucasian man with an acquired naevus of Ota with subtle pigmentation, in which a melanocytic papule developed. The lesion, deceptively, had no clinically suspicious features, but investigation revealed an aggressive cutaneous malignant melanoma, extensive orbital ring melanocytosis and metastatic brain and subsequent liver disease.  相似文献   
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