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991.
992.
Emile van den Akker Timothy J. Satchwell Stephanie Pellegrin Geoff Daniels Ashley M. Toye 《Haematologica》2010,95(9):1594-1598
The study of human erythropoiesis in health and disease requires a robust culture system that consistently and reliably generates large numbers of immature erythroblasts that can be induced to differentiate synchronously. We describe a culture method modified from Leberbauer et al. (2005) and obtain a homogenous population of erythroblasts from peripheral blood mononuclear cells (PBMC) without prior purification of CD34+ cells. This pure population of immature erythroblasts can be expanded to obtain 4×108 erythroblasts from 1×108 PBMC after 13–14 days in culture. Upon synchronized differentiation, high levels of enucleation (80–90%) and low levels of cell death (<10%) are achieved. We compared the yield of erythroblasts obtained from PBMC, CD34+ cells or PBMC depleted of CD34+ cells and show that CD34− cells represent the most significant early erythroid progenitor population. This culture system may be particularly useful for investigating the pathophysiology of anemic patients where only small blood volumes are available. 相似文献
993.
Germline mutations of the MEN1 gene in familial multiple endocrine neoplasia type 1 and related states 总被引:9,自引:0,他引:9
Agarwal SK; Kester MB; Debelenko LV; Heppner C; Emmert-Buck MR; Skarulis MC; Doppman JL; Kim YS; Lubensky IA; Zhuang Z; Green JS; Guru SC; Manickam P; Olufemi SE; Liotta LA; Chandrasekharappa SC; Collins FS; Spiegel AM; Burns AL; Marx SJ 《Human molecular genetics》1997,6(7):1169-1175
Familial multiple endocrine neoplasia type 1 (FMEN1) is an autosomal
dominant trait characterized by tumors of the parathyroids, gastro-
intestinal endocrine tissue, anterior pituitary and other tissues. We
recently cloned the MEN1 gene and confirmed its identity by finding
mutations in FMEN1. We have now extended our mutation analysis to 34 more
unrelated FMEN1 probands and to two related states, sporadic MEN1 and
familial hyperparathyroidism. There was a high prevalence of heterozygous
germline MEN1 mutations in sporadic MEN1 (8/11 cases) and in FMEN1 (47/50
probands). One case of sporadic MEN1 was proven to be a new MEN1 mutation.
Eight different mutations were observed more than once in FMEN1. Forty
different mutations (32 FMEN1 and eight sporadic MEN1) were distributed
across the MEN1 gene. Most predicted loss of function of the encoded menin
protein, supporting the prediction that MEN1 is a tumor suppressor gene. No
MEN1 germline mutation was found in five probands with familial
hyperparathyroidism, suggesting that familial hyperparathyroidism often is
caused by mutation in another gene or gene(s).
相似文献
994.
Laporte J; Guiraud-Chaumeil C; Vincent MC; Mandel JL; Tanner SM; Liechti- Gallati S; Wallgren-Pettersson C; Dahl N; Kress W; Bolhuis PA; Fardeau M; Samson F; Bertini E 《Human molecular genetics》1997,6(9):1505-1511
X-linked recessive myotubular myopathy (XLMTM) is characterized by severe
hypotonia and generalized muscle weakness, with impaired maturation of
muscle fibres. The gene responsible, MTM1, was identified recently by
positional cloning, and encodes a protein (myotubularin) with a tyrosine
phosphatase domain (PTP). Myotubularin is highly conserved through
evolution and defines a new family of putative tyrosine phosphatases in
man. We report the identification of MTM1 mutations in 55 of 85 independent
patients screened by single-strand conformation polymorphism for all the
coding sequence. Large deletions were observed in only three patients. Five
point mutations were found in multiple unrelated patients, accounting for
27% of the observed mutations. The possibility of detecting mutations and
determining carrier status in a disease with a high proportion of sporadic
cases is of importance for genetic counselling. More than half of XLMTM
mutations are expected to inactivate the putative enzymatic activity of
myotubularin, either by truncation or by missense mutations affecting the
predicted PTP domain. Additional mutations are missenses clustered in two
regions of the protein. Most of these affect amino acids conserved in the
homologous yeast and Caenorhabditis elegans proteins, thus indicating the
presence of other functional domains.
相似文献
995.
This study utilized various mouse strains with documented alterations in immune system components to assess their contribution to modify the virulence ofPorphyromonas gingivalis. P. gingivalisW50 was cultivated on blood agar plates, harvested and used to challenge mice by subcutaneous injection on the dorsolateral surface of the back. Soft tissue lesion development was estimated by measuring the area of the spreading lesion formed by this microorganism over a period of 15 days. Challenge of various normal inbred and outbred mouse strains including: BALB/cN, BALB/cJ, BALB/c nu/+, ICR, B10.A(4R), B10.MBR, A/J, C57BL/6J, CBA/CaH, C.B-17/Icv Tacf DF and C3H/HeN with 2×1010bacteria showed similar lesion size among these strains (400 mm2). Genetically deficient mouse strains [C.B-17/Icr Tac (SCID); DBA/2 (C5 deficient); BALB/c nu/nu (T cell deficient); CBA/CaHN-XID/J (B cell deficient) and C3H/HeJ (LPS hyporesponsive)] demonstrated a lesion size which was similar to normal animals. C57BL/6J-BgJ (NK cell deficient) mice exhibited a significantly more severe lesion than the other strains tested. Following healing of the lesions, we initiated a secondary infection of the surviving animals to estimate the acquisition of protective immunity following recovery from the primary infection. Normal mice demonstrated a delayed onset and decrease in lesion size of 15 to 30% compared with the primary infection. In contrast, each of the immunodeficient strains appeared unable to develop immune protection to the secondary challenge. The findings suggest that protection against primary infections withP. gingivalisare mediated by innate immune mechanisms (PMN. NK cells). Additionally, it appears that T-cell-dependent humoral responses are critical to developing immunity to subsequentP. gingivalisinfection. 相似文献
996.
Evaluation of New Quantitative Assays for Diagnosis and Monitoring of Cytomegalovirus Disease in Human Immunodeficiency Virus-Positive Patients 下载免费PDF全文
Isabelle Pellegrin Isabelle Garrigue Christine Binquet Genevieve Chene Didier Neau Pascal Bonot Fabrice Bonnet Herve Fleury Jean-Luc Pellegrin 《Journal of clinical microbiology》1999,37(10):3124-3132
Cobas Amplicor CMV Monitor (CMM) and Quantiplex CMV bDNA 2.0 (CMV bDNA 2.0), two new standardized and quantitative assays for the detection of cytomegalovirus (CMV) DNA in plasma and peripheral blood leukocytes (PBLs), respectively, were compared to the CMV viremia assay, pp65 antigenemia assay, and the Amplicor CMV test (P-AMP). The CMV loads were measured in 384 samples from 58 human immunodeficiency virus (HIV) type 1-infected, CMV-seropositive subjects, including 13 with symptomatic CMV disease. The assays were highly concordant (agreement, 0.88 to 0.97) except when the CMV load was low. Quantitative results for plasma and PBLs were significantly correlated (Spearman rho = 0.92). For PBLs, positive results were obtained 125 days before symptomatic CMV disease by CMV bDNA 2.0 and 124 days by pp65 antigenemia assay, whereas they were obtained 46 days before symptomatic CMV disease by CMM and P-AMP. At the time of CMV disease diagnosis, the sensitivity, specificity, and positive and negative predictive values of CMV bDNA 2.0 were 92.3, 97.8, 92.3, and 97.8%, respectively, whereas they were 92.3, 93.3, 80, and 97. 8%, respectively, for the pp65 antigenemia assay; 84.6, 100, 100, and 95.7%, respectively, for CMM; and 76.9, 100, 100, and 93.8%, respectively, for P-AMP. Considering the entire follow-up, the sensitivity, specificity, and positive and negative predictive values of CMV bDNA 2.0 were 92.3, 73.3, 52.1, and 97.1%, respectively, whereas they were 100, 55.5, 39.4, and 100%, respectively, for the pp65 antigenemia assay; 92.3, 86.7, 66.7, and 97.5%, respectively, for CMM; and 84.6, 91.1, 73.3, and 95.3%, respectively, for P-AMP. Detection of CMV in plasma is technically easy and, despite its later positivity (i.e., later than in PBLs), can provide enough information sufficiently early so that HIV-infected patients can be effectively treated. In addition, these standardized quantitative assays accurately monitor the efficacy of anti-CMV treatment. 相似文献
997.
998.
Quaia E Ulcigrai V Coss M De Paoli L Ukmar M Zanconati F De Pellegrin A De Manzini N Cova MA 《Academic radiology》2011,18(11):1365-1375
999.
1000.