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101.
Fofanova OV Evgrafov OV Polyakov AV Poltaraus AB Peterkova VA Dedov II 《The Journal of clinical endocrinology and metabolism》2003,88(2):820-826
Isolated GH deficiency (IGHD) is characterized by genetic heterogeneity, both in familial and sporadic cases. To determine if this statement can be applied to the Russian population, we performed screening for mutations in the GH-1 gene in children living in Russia with IGHD. Twenty-eight children from 26 families with total IGHD were studied. DNA fragments, covering each of four (2-5) exons of GH-1 were amplified using PCR. Single-strand conformation polymorphism analysis followed by direct DNA sequencing identified five heterozygous mutations of splicing in intron 2, intron 3, and exon 4 of GH-1; three of them were not previously reported. We concentrated here on dominant-negative mutations causing IGHD type II, which were as follows: 1) A>T transversion of the second base of the 3'-acceptor splice site of intron 2 (IVS2 -2A>T); 2) T>C transition of the second base of the 5'-donor splice site of intron 3 (IVS3 +2T>C); 3) G>A transition of the first base of the 5'-donor splice site of intron 3 (IVS3 +1G>A). Our data indicate allelic heterogeneity of IGHD type II (IGHD II). However, all mutations in Russian IGHD II patients affect splicing, a striking difference from the mutation spectrum of other IGHD forms. The IVS2 -2A>T mutation is the first identified mutation in intron 2 of GH-1. The 5'-donor splice site of intron 3 of GH-1 is a mutational hot spot, and the IVS3 +1G>A mutation can be considered to be a common molecular defect in IGHD II in Russian patients. 相似文献
102.
Mesenchymal stem cells remain of host origin even a long time after allogeneic peripheral blood stem cell or bone marrow transplantation 总被引:6,自引:0,他引:6
Rieger K Marinets O Fietz T Körper S Sommer D Mücke C Reufi B Blau WI Thiel E Knauf WU 《Experimental hematology》2005,33(5):605-611
OBJECTIVE: Plasticity of hematopoietic stem cells (HSC) has gained major interest in stem cell research. In order to investigate whether HSC may differentiate into mesenchymal stem cells (MSC), we assessed chimerism in peripheral blood (PB), mononuclear cell fractions (MNC) of bone marrow, and MSC derived from bone marrow (BM) from 27 up to 4225 days after allogeneic transplantation. PATIENTS AND METHODS: We applied fluorescence in situ hybridization using X/Y gene probes in sex-mismatched and STR-PCR in sex-matched patients. MSC could have been generated in 27 of 55 bone marrow samples derived from 20 patients. Fifteen patients received peripheral blood stem cell transplants (PBSCT), including CD34-selected PBSCT in two. Five patients received bone marrow. RESULTS: While all patients had chimerism in PB and MNC of the BM, in all but one patient BM-derived MSC were of recipient origin. This single patient showed reproducibly MSC of donor origin in a frequency of 1% after having received a CD34-selected PBSCT. Looking at graft collections, MSCs were easily generated from BM specimens, while no MSC could be derived from PBSC samples. CONCLUSION: Even though HSC have been found to differentiate into a variety of nonhematological cell types, they usually do not differentiate into MSC after allogeneic transplantation. 相似文献
103.
Recombinant humanized anti-IL-2 receptor antibody (daclizumab) produces responses in patients with moderate aplastic anemia 总被引:9,自引:2,他引:9
In contrast to severe aplastic anemia (sAA), the appropriate management of patients with moderate pancytopenia is unclear. In this study, we examined the efficacy of a humanized monoclonal antibody recognizing interleukin-2 receptor (daclizumab), which has proven to be a successful immunosuppressive agent in solid organ and bone marrow transplantation. We treated 17 patients with moderate aplastic anemia (mAA) with 1 mg/kg every 2 weeks for 3 months. mAA was defined as depression of 2 of the 3 blood counts: absolute neutrophil count 1200/mm3 or less, platelet count 70,000/mm3 or less, hemoglobin level 8.5 g/dL or lower, and absolute reticulocyte count 60,000/mm3 or less. The primary end point of our protocol was a hematologic response in at least one affected peripheral blood value. Daclizumab had little toxicity. Six of the 16 (38%) evaluable patients responded to treatment. Two patients with previously chronic disease showed complete return of normal counts, which were sustained for more than 2 years following treatment. Four patients had single-lineage responses. Two previously transfusion-dependent patients became transfusion independent; one patient with many neutropenia-related infections had a normal neutrophil count following treatment. Daclizumab appears safe; its efficacy in this pilot protocol suggests that expanded study of this monoclonal antibody in immune-mediated bone marrow failure syndrome is warranted. 相似文献
104.
Copolymerization of N‐(prop‐1‐yne‐3‐yl)‐4‐(piperidine‐1‐yl)‐1,8‐naphthalimide with Arylacetylenes into Fluorescent Polyacetylene‐Type Conjugated Polymers 下载免费PDF全文
Radoslava Sivkova Olga Trhlíková Jiří Zedník Jan Sedláček 《Macromolecular chemistry and physics.》2015,216(21):2115-2128
N‐(prop‐1‐yne‐3‐yl)‐4‐(piperidine‐1‐yl)‐1,8‐naphthalimide (PNPr), i.e., the monomer with a terminal ethynyl group and 1,8‐naphthalimide fluorophore, has been successfully copolymerized with a series of monoethynylarenes into well‐soluble high‐molecular‐weight (Mw up to 210 000) linear polyacetylene‐type copolymers containing from 14 to 51 mol% units derived from PNPr. The copolymerization of PNPr with bifunctional 4,4′‐diethynylbiphenyl provides polyacetylene‐type micro/mesoporous fluorescent network containing 8 mol% PNPr units and exhibiting the Brunauer–Emmett–Teller surface of ≈1000 m2 g?1. The copolymerizations (catalyzed with acetylacetonato(norborna‐2,5‐diene)rhodium complex, [Rh(nbd)acac]) proceed smoothly despite the fact that the homopolymerization of PNPr fails. The fluorescence of PNPr (emission at ≈ 510 nm) has been retained after the incorporation of PNPr into the copolymers. The fluorescence of the copolymers can be induced by a direct excitation of PNPr units or via an energy transfer mechanism. In the latter case, the comonomeric units with aromatic hydrocarbon fluorophores (e.g., of the biphenyl‐type) emitting at 380–400 nm (after irradiation with 300 nm UV radiation) serve as energy donors for fluorescent PNPr acceptors. The difference between the wavelengths of the primary absorbed radiation and the finally emitted radiation is 210 nm.
105.
Inés Fajardo-Martos Olga Roda Ramón Zambudio-Periago Aurora Bueno-Cavanillas Fidel Hita-Contreras Indalecio Sánchez-Montesinos 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(3):205-214
Objective
To determine and compare specific factors that could be associated and predictive with successful prosthetic rehabilitation in major lower-limb amputations.Methods
A 15-year long (2000–2014) retrospective observational cohort study was conducted. Two different criteria were used to define successful prosthetic rehabilitation: (1) the ability to walk at least 45 m, regardless of assistive devices; and (2) walking >45 m without other ambulatory aids than one cane (if required). Age, gender, comorbidities, cause and level of amputation, stump characteristics, ulcers in the preserved limb, and time between surgery and physical therapy were examined as predictors of successful prosthetic rehabilitation.Results
A total of 169 patients (61.60 ± 15.9 years) were included. Regarding walking ability with or without walking aids, the presence of ulcers in the preserved limb was individually associated with failed prosthetic rehabilitation (p < 0.001), while being male (OR = 0.21; 95%CI = 0.06–0.80) and transtibial level of amputation (OR = 6.73; 95%CI = 1.92–23.64) were identified as independent predictors of failure and success, respectively. Regarding the criterion of successful rehabilitation, a shorter time until rehabilitation was individually associated with improved walking ability (p < 0.013), while failure could be predicted by comorbidities (OR = 0.48; 95%CI = 0.29–0.78) and age groups of 65–75 years old (OR = 0.19; 95%CI = 0.05–0.78) and over 75 years old (OR = 0.19; 95%CI = 0.04–0.91).Conclusions
Regarding walking ability with or without walking aids, male gender and transtibial level of amputation are independently associated with failure and success respectively, whereas older age and comorbidities can predict failed prosthetic rehabilitation when assistive walking devices are considered. Future prospective cohort studies are needed to confirm these findings. 相似文献106.
Carlos A. Ramos Rayne Rouce Catherine S. Robertson Amy Reyna Neeharika Narala Gayatri Vyas Birju Mehta Huimin Zhang Olga Dakhova George Carrum Rammurti T. Kamble Adrian P. Gee Zhuyong Mei Meng-Fen Wu Hao Liu Bambi Grilley Cliona M. Rooney Helen E. Heslop Gianpietro Dotti 《Molecular therapy》2018,26(12):2727-2737
107.
To access the calibration of a predictive model in a survival analysis setting, several authors have extended the Hosmer–Lemeshow goodness‐of‐fit test to survival data. Grønnesby and Borgan developed a test under the proportional hazards assumption, and Nam and D'Agostino developed a nonparametric test that is applicable in a more general survival setting for data with limited censoring. We analyze the performance of the two tests and show that the Grønnesby–Borgan test attains appropriate size in a variety of settings, whereas the Nam‐D'Agostino method has a higher than nominal Type 1 error when there is more than trivial censoring. Both tests are sensitive to small cell sizes. We develop a modification of the Nam‐D'Agostino test to allow for higher censoring rates. We show that this modified Nam‐D'Agostino test has appropriate control of Type 1 error and comparable power to the Grønnesby–Borgan test and is applicable to settings other than proportional hazards. We also discuss the application to small cell sizes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
108.
109.
Gabriella Nosso Brunella Capaldo Sara Cocozza Olga Vaccaro 《Clinical Case Reports》2015,3(12):1030-1033
We show the long‐term efficacy and safety of modified biliopancreatic diversion for the treatment of LPL‐deficiency. How this option compares with gene therapy is difficult to evaluate due to limited experience. Surgery may be the first option in patients in whom medical therapy is ineffective and gene therapy not applicable. 相似文献
110.
Olga Ivanitskaya MD PhD Elena Andreeva MD PhD Natalia Odegova MD 《Journal of ultrasound in medicine》2018,37(4):1039-1042
A ventricular septal aneurysm is a rare heart defect located in the muscular or membranous part of the septum. Muscular ventricular septal aneurysms are usually isolated, with a favorable prognosis. Membranous ventricular septal aneurysms are often associated with other heart anomalies, could result in serious complications, and may require surgical treatment. We describe 2 cases of prenatally diagnosed ventricular septal aneurysms: an isolated membranous ventricular septal aneurysm with a good outcome, which was initially misdiagnosed as an atrioventricular septal defect; and a muscular ventricular septal aneurysm associated with a hypoplastic aortic arch and severe hydrocephaly, which resulted in termination of the pregnancy. To our knowledge, the combination of a muscular ventricular septal aneurysm with an extracardiac anomaly has not been reported previously. 相似文献