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631.
The rare alpha-thalassemia-1 of blacks is a zeta alpha-thalassemia-1 associated with deletion of all alpha- and zeta-globin genes 总被引:7,自引:0,他引:7
Restriction endonuclease mapping with alpha and zeta-globin gene probes showed differences between the alpha-thalassemia-1 (alpha-thal-1) condition in two patients with HbH disease. One patient had the rare black type of alpha-thal-1 together with alpha-thal-2 and HbS heterozygosities. The second patient was a Laotian child with HbE, Hb Constant Spring (alpha-thal-2), and alpha-thal-1 heterozygosities. The diagnoses were based on clinical, hematologic, and biochemical data. Whereas DNA fragments hybridizing to a zeta-probe were obtained from the Laotian type of alpha-thal-1, neither alpha nor zeta-gene fragments could be identified deriving from the black type of alpha-thal-1. Therefore, the black type of alpha-thal-1 is associated with a deletion of the entire zeta 2-psi zeta-psi alpha-alpha 2-alpha 1 gene complex and can be considered a zeta alpha-thal-1. It is likely that homozygosity for such a condition will lead to embryonic wastage, explaining the absence of hydrops fetalis in blacks. 相似文献
632.
Serological confirmation of human T-lymphotropic virus type I infection in healthy blood and plasma donors 总被引:10,自引:0,他引:10
Anderson DW; Epstein JS; Lee TH; Lairmore MD; Saxinger C; Kalyanaraman VS; Slamon D; Parks W; Poiesz BJ; Pierik LT 《Blood》1989,74(7):2585-2591
We wished to develop criteria for serological confirmation of human T- lymphotropic virus type I (HTLV-I) infection in healthy donors. Selected serum or plasma samples reactive by HTLV-I enzyme immunosorbent assay or gel-agglutination assays with at least one viral- specific band on Western immunoblot (WIB) were tested in six laboratories by four WIBs and four radioimmunoprecipitation assays (RIPAs) for antibodies to HTLV-I proteins encoded by gag (p19 and p24), env (gp46 and/or gp61), and tax (p40x) genes. One hundred forty-two donor sera were obtained from 38 Japanese, 69 American, and 35 Caribbean blood or plasma donors. Among these samples, WIB assays appeared more sensitive to p24 antibodies, whereas RIPAs were significantly more sensitive to gp61 antibodies. All sera (137) with gp61 antibodies had p24 antibodies. Of the 137 sera positive for p24 and gp61 antibodies, p19 antibodies were detected in 129 sera, and p40x antibodies were detected in 108. In sera with p19 antibodies and antibodies to env- or tax-encoded proteins, p24 antibodies were always present. Antibodies to p40x were not found in the absence of gp61 antibodies. Virological evidence of infection was found in seven American donors by lymphocyte coculture (one HTLV-I, one HTLV-II) or by polymerase chain reaction (three HTLV-I, two HTLV-II). Sera from all seven donors showed p24 and gp46 and/or gp61 antibodies. We suggest that seroreactivity to both p24 and gp46 and/or gp61 by WIB or RIPA or both are suitable criteria to confirm but not to distinguish HTLV-I and HTLV-II infections. 相似文献
633.
BC McLeod ; TH Price ; H Owen ; D Ciavarella ; I Sniecinski ; MJ Randels ; JW Smith 《Transfusion》1998,38(10):938-943
BACKGROUND: Apheresis donation is considered safe, but the incidence of adverse effects has not been determined in a large multicenter series of donations with modern instruments. STUDY DESIGN AND METHODS: The Hemapheresis Committee of the American Association of Blood Banks devised a uniform questionnaire that asked about 32 specific adverse effects. Transient paresthesia and mild vasovagal events were excluded. A survey was conducted in 1995; 17 centers returned 19,611 responses concerning 250 to 2,000 consecutive apheresis donations per center. RESULTS: Six hundred adverse effects were reported in 428 donations (2.18% of donations). Pain or hematoma at a venipuncture site was the most common response (1.15% of donations); only 203 donations had other (nonvenipuncture) adverse effects (1.04%). Total and nonvenipuncture rates were, respectively, 4.84 and 2.92 percent for 2,295 first donations and 1.78 and 0.77 percent for 17,303 repeat donations (p < 0.001). Rates of nonvenipuncture symptoms in first and repeat donations were, respectively, citrate-induced nausea and/or vomiting, 0.87 and 0.27 percent; tetany, 0.09 and 0.04 percent; pallor and/or diaphoresis, 1.87 and 0.32 percent; vasovagal nausea and/or vomiting, 0.87 and 0.13 percent; syncope and/or seizure, 0.39 and 0.04 percent; and chills and/or rigors, 0.31 and 0.01 percent. The overall rate of donor unconsciousness was 0.08 percent. Hemolysis was reported twice. Clotting or leakage occurred in 0.08 percent of donations, and inability to return blood occurred in 0.16 percent. No life-threatening adverse effects were reported. Procedure-specific nonvenipuncture rates were 1.05 percent of 17,584 platelet donations, 0.67 percent of 594 white cell donations, and 0.37 percent of 1,354 plasma donations. Center-specific rates varied from 0.32 to 6.81 percent of donations for total adverse effects and from 0.11 to 2.92 percent of donations for nonvenipuncture events. CONCLUSION: Apheresis donation is a safe undertaking, suitable for voluntary blood donors, with a very low risk of serious adverse effects. The risk of unconsciousness is lower than that found in many studies of whole-blood donation. 相似文献
634.
BACKGROUND: The clinical utility of polymorphonuclear neutrophil (PMN) transfusion therapy has been compromised, in part, by the inability to obtain sufficient quantities of functional neutrophils from donors. To define the optimal conditions for mobilization of PMNs in granulocyte donors, the effects of granulocyte-colony-stimulating factor (G-CSF) and dexamethasone, separately and in combination, on PMN counts in normal volunteers were compared. STUDY DESIGN AND METHODS: Five normal subjects were randomly assigned to each of the following single-dose regimens in 5 consecutive weeks: 1) G-CSF, 300 micrograms given subcutaneously; 2) G-CSF, 600 micrograms subcutaneously: 3) dexamethasone, 8 mg given orally; 4) G-CSF, 300 micrograms subcutaneously, plus dexamethasone, 8 mg orally; and 5) G-CSF, 600 micrograms subcutaneously, plus dexamethasone 8 mg orally. Venous blood was collected at 0, 6, 12, and 24 hours after drug administration for the determination of absolute neutrophil counts (ANCs). RESULTS: Maximal ANC was achieved at 12 hours after each regimen, except dexamethasone alone (maximum, 24 hours). Dexamethasone significantly increased the maximal ANC induced by either dose of G-CSF alone (p < 0.05). The greatest mobilization of PMNs occurred after the administration of G-CSF (600 micrograms) and dexamethasone (8 mg); the ANC increased from a mean baseline value of 3,594 per microL to 43,017 per microL at 12 hours. All of the drug regimens were well tolerated. CONCLUSION: Dexamethasone significantly increases the level of neutrophilia induced in normal subjects by G-CSF. The combination of dexamethasone and G-CSF (at the dosages used in this study) is a convenient, well-tolerated regimen for the mobilization of PMNs in the peripheral blood of granulocyte donors. Moreover, the optimal quantitative yield of PMNs is likely to be achieved by leukapheresis 12 hours after drug administration. 相似文献
635.
D Darbar MB ChB AB Bridges MB ChB MRCP R Roberts DPhil MRCP TH Pringle MD FRCP 《International journal of clinical practice》1995,49(3):166-167
SUMMARY Cor triatriatum is a rare congenital cardiac malformation, and in its most common form is characterised by a membrane that separates the left atrium into a proximal and distal chamber. First manifestation in adulthood has been reported previously, but at 67 years of age this patient is one of the oldest to present for the first time. It was diagnosed after a probable TIA, episodic vertigo and central retinal artery occlusion. The value of echocardiography in patients with neurological disease of presumed embolic origin is demonstrated here. 相似文献
636.
M Adams ; TH Lee ; MP Busch ; J Heitman ; GJ Marshall ; GF Gjerset ; JW Mosley 《Transfusion》1993,33(6):504-508
Storage of lymphocytes for later use in prospective epidemiologic studies of blood donors and transfusion recipients has been limited by the cost of separating peripheral blood mononuclear cells (PBMCs). When the Transfusion Safety Study began in 1985, it was decided to establish a cell repository of cryopreserved buffy coat (BC) samples, and thus far over 20,000 samples have been accumulated from enrolled subjects. To determine if these specimens could be used for polymerase chain reaction, a simple thawing and pelleting technique for recovering hemoglobin-free total white cells (WBCs) was developed. To validate the technique, parallel analysis was conducted of BCs, whole blood (WB), and PBMC samples from human immunodeficiency virus type 1 (HIV-1)- seropositive subjects. Immediate postthaw cell courts of 29 frozen- thawed (F-T) WB and BC samples averaged 90 percent of the prefreeze (input) values. Representative WBC populations were obtained by immediate pelleting. Amplification of HIV-1 gag sequences from F-T BCs and F-T WB was 94 and 75 percent, respectively, which is as sensitive as that obtained with freshly separated PBMC lysates. Quantitative HIV- 1 proviral load analysis by serial dilution of 23 F-T BCs and 8 WB lysates showed results comparable to those obtained with lysates of fresh PBMCs. Values for WBC differential and immunophenotyping could be applied to express viral load relative to total WBCs, PBMCs, or CD4+ cells. These results establish the basis for simplified virologic analysis of cryopreserved BC or WB specimens. 相似文献
637.
Neutrophil transfusions: kinetics and functions of neutrophils mobilized with granulocyte-colony-stimulating factor and dexamethasone 总被引:4,自引:0,他引:4
BACKGROUND: The collection of adequate numbers of neutrophils (polymorphonuclear leukocytes, PMNs) from normal donors has long hampered the development of neutrophil transfusion therapy. The stimulation of donors with granulocyte-colony-stimulating factor (G- CSF) plus dexamethasone is a promising way of improving PMN collections. STUDY DESIGN AND METHODS: Sixteen normal subjects received G-CSF (600 micrograms subcutaneously) and dexamethasone (8 mg by mouth) 12 hours before leukapheresis. Measurements included PMN morphology, immunophenotype analysis, chemiluminescence, bactericidal activity, in vivo kinetics, and adverse effects. RESULTS: A mean of 77.4 +/− 6.4 × 10(9) PMNs was collected with each leukapheresis; 14 percent were bands. PMNs had increased surface expression of CD11b, CD18, CD14, CD32, and CD64. Bactericidal capacity against Staphylococcus aureus was normal. Inducible respiratory burst was maintained, although the responses to some agonists were diminished. Returned leukapheresis cells labeled with 3H-diisopropylfluorophosphate had a modestly decreased percentage of recovery and circulated with a prolonged half- life. Migration of these cells to skin chambers was approximately equal to that of the subjects' own blood PMNs. Adverse effects included transient bone pain, headache, hunger, and insomnia. CONCLUSIONS: Precollection treatment of leukapheresis donors with G-CSF plus dexamethasone is an effective way to enhance the collection of PMNs with normal or near-normal functional properties for PMN transfusion therapy. 相似文献
638.
TH.M. STARINK R. HAUSMAN L. VAN DELDEN† H. NEERING 《The British journal of dermatology》1977,97(2):167-177
A typical fibroxanthoma is a solitary tumour of the skin, which occurs mostly on sun-exposed areas in elderly people. The diagnosis can only be made with certainty on the typical histological findings, which suggest a bizarre malignant tumour. Although metastasizing tumours are reported in the literature, the authors believe that the true atypical fibroxanthoma is benign. Correct diagnosis obviates the need for unnecessary radical surgery. The possibility of atypical fibroxanthoma should always be considered when a histologically bizarre tumour is found on sun-damaged or irradiation-damaged skin in elderly patients or on previously traumatized sites. In this paper five cases are added to the 346 cases culled from the literature. Electron microscopic investigations in one case demonstrated cells with delicate cytoplasmic fibrils in small bundles. This does not necessarily suggest filaments of myofibroblasts, as has been previously reported. 相似文献
639.
Three groups of glaucoma patients, treated topically with various beta-blocking agents, were studied for mucocutaneous side-effects of long-term therapy. In five of eleven patients with ocular and/or periocular dermatitis as an adverse reaction to long-term treatment with metoprolol eye drops a dermatitis, reproducible by patch tests with pure metoprolol 3%, was demonstrable. Histopathological examination of positive patch tests examined in three cases showed a picture compatible with a delayed type of hypersensitivity. Four atenolol treated patients showed adverse reactions, but negative patch tests to atenolol were found. In addition new data are reported in favour of cross-reactivity between certain beta-blocking agents. 相似文献