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Fucosidosis: four new mutations and a new polymorphism 总被引:2,自引:0,他引:2
Seo Hee-Chan; Willems Patrick J.; Kretz Keith A.; Martin Brian M.; O'Brien John S. 《Human molecular genetics》1993,2(4):423-429
Fucosidosis is a rare lysosomal storage disease due to a nearlycomplete deficiency of -L-fucosidase (EC 3.2.1.51
[EC]
). In thisstudy, all 8 exons of the -L-fucosidase structural gene (FUCA-1)were amplified by PCR methods, and the amplified products weresubcloned and sequenced. Five patient groups with fucosidosiswere selected according to their ethnic backgrounds and haplotypesfor RFLPs in FUCA-1. Four presumptive disease causing mutationswere detected: 1) A major deletion of DNA containing the lasttwo exons of FUCA-1 in two Algerian siblings. 2) A G to T mutationin exon 6 resulting in an in-frame termination codon (E375X)in eight Hispanic patients from Colorado and New Mexico. 3)A G to A mutation (G60D) in exon 1 in four Italian patientsand in three related French-American (Cajun) patients. ThisG60D mutation creates a unique site for Afl III. 4) A frameshiftmutation resulted from a two-base deletion in exon 2 (K151fs)in an Italian patient. This deletion obliterates a unique BstXIsite and creates a new BpmI site, and was found in only thispatient and in only one allele. The rationale for proposingthese defects as disease causing mutations includes pedigreeanalysis and the predicted consequences of each defect uponthe activity and the concentration of the enzyme. An A to Gtransition (Q281R) in exon 5 was found to be present in homozygousform in affected patients and also in normal subjects; it appearsto be a newly identified polymorphism. It causes a charge changeand may be responsible for the electrophoretic variant phenotypeof fucosidosis. This polymorphism is inherited concordant withthe RFLP PvuIIBglI haplotype 2 2, 2 2.The 4 new mutations identified here comprise 70% of allelesof the 25 fucosidosis patients in our study. 相似文献
44.
Carlos M. Villaln Eduardo Ramírez‐San Juan Araceli Snchez‐Lpez Guadalupe Bravo Edwin W. Willems Pramod R. Saxena David Centurin 《Basic & clinical pharmacology & toxicology》2003,92(4):165-172
Abstract: The present study investigated the effects of dopamine on the canine external carotid circulation. One min. intracarotid artery (i.c.) infusions of dopamine (10–310 μg min.?1) produced dose‐dependent decreases in the canine external carotid conductance without affecting blood pressure or heart rate. This effect was mimicked by the D1/2‐like receptor agonist apomorphine (1–310 μg min?1), but not by the D2‐like receptor agonist, bromocriptine (31–310 μg min.?1). In contrast, fenoldopam (1–310 μg min.?1, intracarotid), a D1‐like receptor agonist, produced dose‐dependent increases in external carotid conductance. The vasoconstrictor response to dopamine was abolished after intravenous administration of the antagonists, phentolamine (α1/2; 2000 μg kg?1) or rauwolscine (α2; 100 μg kg?1), but remained unaffected after prazosin (α1; 100 μg kg?1) or haloperidol (D2‐like; 1000 μg kg?1). Interestingly, after phentolamine not only were the vasoconstrictor responses to dopamine abolished, but even a dose‐dependent vasodilator component was unmasked. These vasodilator responses to dopamine remained unchanged after intravenous haloperidol or propranolol (1000 μg kg?1 each). On the other hand, the vasodilator responses to fenoldopam, which remained unchanged after intravenous saline (0.1 ml kg?1), propranolol (1000 μg kg?1) or vagosympathectomy, were abolished by the D1‐like receptor antagonist, SCH‐23390 (10 μg kg?1). Lastly, the responses to dopamine and fenoldopam were not significantly altered after intraperitoneal pretreatment with reserpine (5 mg kg?1; ?24 hr). The above results suggest that the canine external carotid vasoconstrictor responses to dopamine: (i) are mainly mediated by α2‐adrenoceptors; and (ii) overshadow a vasodilator component, which involves vascular D1‐like receptors. 相似文献
45.
Objectives: Evaluate the age-dependency of ciliary beat frequency (CBF) in biopsies after ciliogenesis in culture. Study Design: Retrospective analysis of CBF and ciliary ultrastructure in biopsies and after ciliogenesis from 203 individuals, aged 3 months to 74 years. Methods: All patients with successful culture were included. Ciliogenesis was obtained using the sequential monolayer-suspension culture technique for dissociated nasal epithelial cells. CBF was measured using computerized microscope photometry. Secondary ultrastructural abnormalities were evaluated in transmission electron microscopy. Results: There was no correlation between age and CBF, in either the biopsies (7.0 ± 2.6 Hz; n = 113) or after ciliogenesis in culture (8.1 ± 1.3 Hz; n = 203). Even in individuals older than 70 years, CBF was normal in bioptic material (6.7 ± 1.7 Hz) and after ciliogenesis in culture (7.9 ± 1.0 Hz). Also, in individuals less than 1 year of age CBF was normal in biopsies as well as after ciliogenesis. CBF correlated inversely with the percentage of secondary ultrastructural abnormalities in the biopsies as seen with transmission electron microscopy: 8.1 ± 1.8 Hz when ciliary ultrastructure was normal and 3.5 ± 3.3 Hz in cases of severe secondary ciliary dyskinesia. After ciliogenesis in culture, ciliary ultra-structure was always normal, as was CBF. Conclusion: CBF is age independent but correlates with secondary ultrastructural abnormalities. CBF after ciliogenesis in culture is the intrinsic one. 相似文献
46.
Willems PW van den Bergh WM Vandertop WP 《Journal of neurology, neurosurgery, and psychiatry》2000,68(4):508-510
A case of thoracic intradural extramedullary arachnoid cyst is presented in which an intramedullary low grade glioma was suspected preoperatively. The cyst was widely fenestrated and postoperatively, the patient experienced considerable improvement in her symptoms. As postoperative MRI studies also showed resolution of the intramedullary changes we regard the intramedullary changes as a result of the cyst, without the existence of primary medullary pathology. To our knowledge an arachnoid cyst, to date, has not been described as the cause of syringomyelia. As radiological findings can be misleading, extramedullary pathology, located more cranially, should be ruled out when treating cystic medullary changes. 相似文献
47.
C Matthys M Bilau Y Govaert E Moons S De Henauw J L Willems 《Food and chemical toxicology》2005,43(2):271-278
Acrylamide has recently been found in a range of heat treated food items. As it is a neurotoxic agent and a probable, human carcinogen (IARC 2A), human exposure to this chemical might constitute an important public health issue. The purpose of the study was to estimate the acrylamide intake in Flemish adolescents (based on 7-day food record) and to evaluate the possible health risks due to the exposure. The Belgian Federal Agency for the Safety of the Food Chain collected 150 food items from different supermarkets and restaurants to analyse the acrylamide level. The limit of quantitation was 30 microg acrylamide/kg foodstuffs. Exposure modelling was based on Monte Carlo simulations. The estimated dietary intake of acrylamide per person given as the 5th, 50th and 95th percentile were 0.19, 0.51 and 1.09 mircog/kg bw/d. Bread, despite its low acrylamide content, is relevant as a source of acrylamide exposure at the lower percentiles. At higher percentiles the contribution of French fries and crisps is more important. It must be emphasised that the exposure assessment has several limitations. Risk of neurotoxicity seems negligible. The relevance of current intake levels in terms of cancer risk remains a subject of debate. 相似文献
48.
49.
Laparoscopic adjustable gastric banding (LAGB) is an often performed bariatric procedure for morbid obesity. Several complications
are known, including surgery and port-side-associated complications. As rare but serious late complication of LAGB, we describe
a 50-year-old patient with periodic incomplete intestinal constriction due to the silicone connecting tube, 4 years after
laparoscopic adjustable gastric banding was performed. Abdominal CT scan showed an obstructive ileus due to a loop in the
connecting tube. After surgical removal of the connecting tube, the patient recovered without sequelae. 相似文献
50.
van Halteren HK Bongaerts GP Verhagen CA Kamm YJ Willems JL Grutters GJ Koopman JP Wagener DJ 《Journal of cancer research and clinical oncology》2004,130(4):211-216
Background Within hypoxic tumor regions anaerobic dissimilation of glucose is the sole source of energy generation. It yields only 5% of the ATP that is normally gained by means of oxidative glucose catabolism. The increased need for glucose may aggravate cancer cachexia. We investigated the impact of recombinant human erythropoietin (RhEPO) and increased inspiratory oxygen concentrations on weight loss in tumor-bearing mice.Methods Fragments of the murine C26-B adenocarcinoma were implanted in 60 BALB/c-mice. The mice were divided into four groups and assigned to: (A) no treatment; (B) RhEPO- administration (25 IU daily from day 1–11, three times per week from day 12); (C) RhEPO and 25% oxygen; and (D) RhEPO and 35% oxygen. Three control groups of four healthy mice each received the same treatment as groups A, B, and D, respectively. Hematocrit and hemoglobin levels, tumor volume, and body weight were monitored. At day 17 the experiment was terminated and the serum lactate concentration was measured. The tumors were excised and weighed and, for each mouse, the percentage weight loss was calculated. The impact of tumor weight and the treatments on lactate concentration and weight loss was evaluated.Results Significant positive correlations were found between tumor weight and lactate concentration and between tumor weight and percentage weight loss. In the mice with the largest tumors, RhEPO displayed a significant weight loss-reducing effect, and a significant negative correlation was found between hemoglobin concentration and weight loss. An oxygen-rich environment did not appear to influence weight loss.Conclusion Anaerobic glycolysis in a growing C26-B tumor is related to weight loss. RhEPO administration results in a reduction of the percentage weight loss; this effect is probably mediated by an increased hemoglobin concentration.This study was financially supported by a grant from Ortho Biotech, a division of Janssen Cilag, Tilburg, the Netherlands 相似文献