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101.
Blood glucose normalization upon transplantation of human embryonic pancreas into beta-cell-deficient SCID mice 总被引:4,自引:3,他引:1
M. Castaing B. Péault A. Basmaciogullari I. Casal P. Czernichow R. Scharfmann 《Diabetologia》2001,44(11):2066-2076
Aims/hypothesis: Transplanting human pancreatic islet beta cells could represent a radical new treatment of Type I (insulin-dependent) diabetes
mellitus. However, beta cells available for grafting are scarce and finding new sources of such cells would be crucial for
any cell therapy for diabetes. Undifferentiated precursor cells present in the human embryonic pancreas could represent such
a source.
Methods: We grafted human embryonic pancreases (6–9 weeks of development) that contain very few beta cells onto NOD/scid mice.
Results: The human pancreatic tissue grew, increasing in weight 200 times within six months and endocrine cells differentiated, the
number of human beta cells being increased by a factor 5000. Finally, the developed human endocrine tissue was mature enough
to control the glycaemia of mice deficient in endogenous beta cells.
Conclusion/interpretation: Human embryonic pancreas represent a source of immature cells that can proliferate and differentiate into mass beta cells
after transplantation. Transplantation of human embryonic pancreas into NOD/scid mice is a useful model for understanding the development of the human pancreas during prenatal life. [Diabetologia (2001)
44: 2066–2076]
Received: 12 June and in revised form: 17 July 2001 相似文献
102.
Liu J Zheng BS Aposhian HV Zhou YS Chen ML Zhang AH Waalkes MP. 《Journal of the peripheral nervous system : JPNS》2002,7(3):208-208
Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g., 62, 67, and 69). However, the desired in vivo potency in chronically diabetic rats, ED90 less than or equal to 5 mg/kg/day, was achieved only through further modification of the piperazine linker. Several members of this family, including 86, showed better than the targeted potency with ED90 values of 1-2 mg/kg/day. Compound 86 was further profiled and found to be a selective inhibitor of sorbitol dehydrogenase, with excellent pharmacodynamic/pharmacokinetic properties, demonstrating normalization of sciatic nerve fructose in a chronically diabetic rat model for approximately 17 h, when administered orally at a single dose of 2 mg/kg/day. 相似文献
103.
S Paeschke N Horn C Fotopoulou A Zambon-Bertoja A Sollwedel ML Zenclussen P Casalis J Dudenhausen HD Volk F Chen A Zenclussen 《American journal of reproductive immunology (New York, N.Y. : 1989)》2005,54(2):120-121
The acceptance of the semiallogeneic fetus within the maternal environment requires tolerance mechanisms not fully characterized yet. Normal pregnancy is known to be associated with a Th2 profile. Furthermore, T-regulatory cells were proposed to regulate the Th2/Th1 balance at early stages of pregnancy. Treg may avoid the shift to a Th1 profile preventing miscarriage. Accordingly, spontaneous abortion is characterized by a Th1 dominance and diminished levels of Tregulatory cells (Treg). The major aim of the present work was to investigate if pre-eclampsia, a late immunological complication of pregnancy, is characterized by similar hallmarks. Therefore, we measured the surface antigens CD4, CD25, CD8, CTLA4 (as well as the secretion of IL-10) in peripheral blood from patients suffering from pre-eclampsia (n = 8) and age-matched patients undergoing normal pregnancies (n = 9) by 4-colour flow-cytometry. We were not able to find any significant differences in the levels of CD4+ , CD25+ , CD8+ , CTLA4, CD4+ /CD25+ , CD4+ /CD25bright , CD4+ /CTLA4, CD25+ /CTLA4, CD4+ /CD25+ /CTLA4, CD8+ /CD25+ , CD8+ /CTLA4 or CD8+ /CD25+ /CTLA4 cell subsets. Our data suggest that Treg may not participate in the onset of pre-eclampsia and suggest other regulatory mechanisms during late pregnancy. 相似文献
104.
105.
Identification of pneumococcal serotypes from culture-negative clinical specimens by novel real-time PCR 总被引:1,自引:0,他引:1
D. Tarragó A. Fenoll D. Sánchez-Tatay L. A. Arroyo C. Muñoz-Almagro C. Esteva W. P. Hausdorff J. Casal I. Obando 《Clinical microbiology and infection》2008,14(9):828-834
Pneumococcal parapneumonic empyema is an increasingly common complication in children. Conventional microbiological cultures indicate bacterial causes in as few as 8% of cases; therefore, there is a vital need for new molecular methods of detection and diagnosis. The development and clinical evaluation of real-time PCR-based assays to detect the pneumococcal capsular wzg gene of all serotypes tested are reported here, and 24 of them have been identified in clinical specimens. Using real-time PCR assays with highly specific TaqMan MGB probes that target DNA sequences within the capsular polysaccharide gene cluster, it was possible to differentiate serotypes 1, 3, 5, 4, 6A, 6B, 7F/A, 8, 9V/A/N/L, 14, 15B/C, 18C/B, 19A, 19F/B/C, 23F and 23A. These assays showed high sensitivity (five to ten pneumococcal DNA equivalents) and they were validated with 175 clinical isolates of known serotypes. The clinical value of this approach was demonstrated by analysis of 88 culture-negative pleural fluids from children diagnosed with parapneumonic empyema in three Spanish hospitals. Pneumococcal DNA was detected in 87.5% of pleural fluids, and serotypes 1, 7F and 3 were responsible for 34.3%, 16.4% and 11.9%, respectively, of cases of parapneumonic empyema in children. Such molecular methods are critical for the diagnosis of invasive pneumococcal disease and continued epidemiological surveillance in order to monitor serotype vaccine effectiveness. 相似文献
106.
107.
108.
Childhood scoliosis: MR imaging 总被引:2,自引:0,他引:2
Nokes SR; Murtagh FR; Jones JD d; Downing M; Arrington JA; Turetsky D; Silbiger ML 《Radiology》1987,164(3):791-797
The spinal cords of 28 scoliosis patients between the ages of 1 month and 17 years were examined with magnetic resonance (MR) imaging. Complete visualization was obtained in all cases. In 15 patients (53%) neuropathologic abnormalities demonstrated by MR imaging significantly affected their clinical course, including tethered cords (n = 7), syringomyelia (n = 5), Arnold-Chiari I malformation (n = 4), spinal cord tumors (n = 2), Arnold-Chiari II malformation (n = 3), and diastematomyelia (n = 1). The advantages of MR imaging in the evaluation of the scoliotic spine in children include a high sensitivity for the occult conditions associated with scoliosis, good anatomic demonstration of the cord, and absence of bone artifacts. MR imaging is recommended as a primary imaging modality in scoliosis, following conventional radiography. 相似文献
109.
Cyano and amidino flavans, isoflavans and 3(2H)-isoflavenes were synthesized in order to study their in vitro antirhino-virus activity, by comparison with the known corresponding chloro derivatives. The activity of the new compounds was evaluated on rhinovirus 1 B infected HeLa cell cultures by examining their ability to interfere with viral cytopathic effect and with plaque formation. It was found that generally the cyano derivatives behave like the chloro compounds, whereas the amidino derivatives show a lower activity, although always dependent on the position of substituent. 相似文献
110.
Digital imaging of the chest 总被引:4,自引:0,他引:4
Fraser RG; Sanders C; Barnes GT; MacMahon H; Giger ML; Doi K; Templeton AW; Cox GG; Dwyer SJ d; Merritt CR 《Radiology》1989,171(2):297-307
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented. 相似文献