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11.
12.
Genetically modified fibroblasts induce angiogenesis in the rat epigastric island flap 总被引:2,自引:0,他引:2
H.-G. Machens Jeffrey R. Morgan Francois Berthiaume Peter Stefanovich Ralf Reimer Alfred C. Berger 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1998,383(5):345-350
Methods: Gene therapy was tested for inducing functional angiogenesis in the superficial rat epigastric island flap to allow earlier
pedicle division. Autologous rat fibroblasts were grown, harvested, cultured and retrovirally transfected to produce platelet-derived
growth factor AA (PDGF-AA), an angiogenetically active protein. Stable gene expression was monitored by PDGF-AA enzyme-linked
immunosorbent assay (ELISA). One hundred and eighty animals were divided into three groups (I–III) and a bilateral flap created
in each animal. In all experiments, the right-sided flap was subjected to experimental treatment and the left-sided flap served
as control (1 ml saline 0.9%). During flap elevation, group I received 5×106 GMFB (genetically modified fibroblasts) plus 1 ml Dul-becco's modified Eagle's medium. Group II was treated with 5×106 NMFB (non-modified fibroblasts) plus 1 ml medium and group III received 1 ml medium only. The flaps were sutured back and
the vascular pedicle was bilaterally ligated and divided in each of ten animals during the following 6 days. After 7 days,
the flaps were harvested, the amount of necrosis measured and histologically examined. Results: The GMFB produced up to 560 times more PDGF-AA than the NMFB, measured by ELISA. The GMFB-treated flaps tolerated surgical
division of the vascular pedicle significantly earlier than groups II and III. Histologically, fibroblasts persisted in all
flaps of groups I and II, without major inflammatory reaction. In all GMFB-treated flaps, massive angiogenesis could be demonstrated.
Conclusion: By means of retroviral gene transfer, autologous rat fibroblasts can be genetically modified for stable expression of the
PDGF-A gene to produce high amounts of PDGF-AA, which is angiogenetically active. After injection into the panniculus carnosus,
these cells induce functional angiogenesis to permit earlier division of the vascular pedicle in this flap model.
Received: 5 January 1998 / Accepted: 17 June 1998 相似文献
13.
14.
M Hamoir M Remacle A Youssif D Moulin G Francois D Claus A Kahn Y Frederickx 《Head & neck surgery》1988,10(6):406-410
Parapharyngeal cystic hygroma is a rare tumor of the neck. This report describes two cases in which surgical resection was necessary to overcome sudden airway obstruction and details the surgical technique. These cases were considered "near misses" for sudden infant death syndrome (SIDS) and were revealed by computed tomography (CT) and echography to be parapharyngeal cystic hygroma. The location of this malformation could have produced sudden airway collapse and be erroneously diagnosed as SIDS. The postoperative follow-up was satisfactory and no recurrence was detected. We believe CT and echography should be included in the evaluation of such cases. 相似文献
15.
Ibraheim A. Naga Francois B. Sakla Zaiful A. Girgis Fathy A. State 《Developmental dynamics》1970,129(1):53-63
Twenty-five rabbits were used to study the effect of glossopharyngeal nerve transection upon the number, size and cellular constitution of the taste buds. The glossopharyngeal nerve was cut on one side, the other being left undisturbed as a control. The animals were sacrificed in groups of three after 7, 10, 14, 21, and 30 days, and 2 and 4 months after the operation. Seven days after the operation the size and number of intragemmal cells were decreased in the taste buds. The taste pores with hairlets passing through them disappeared. The number of taste buds on circumvallate papillae decreased. After ten days taste buds in both types of papillae showed signs of degeneration. Fourteen days after the operation there was a marked decrease in size and number of taste buds. The circumvallate papillae now possessed no taste buds. After 21 days few taste buds were present in foliate gutters. These consisted of one or two sustentacular cells each. After 30 days there were no taste buds on foliate papillae, and thickness of the epithelium lining the gutters was decreased. Two or four months after denervation, the foliate gutters were shallow and some had become flattened. The importance of the gustatory nerve for development and maintenance of the normal status of the taste buds is discussed. 相似文献
16.
Rats with thalamic taste nuclei lesions were adapted to a 23 hr 50 min deprivation schedule and then presented with 0.125 percent saccharin followed by an injection of LiCl or saline. When retested with saccharin, animals with lesions showed a marked attenuation in taste aversion as compared to controls. 相似文献
17.
Rapid detection of methicillin-resistant Staphylococcus aureus directly from sterile or nonsterile clinical samples by a new molecular assay 总被引:13,自引:0,他引:13
Francois P Pittet D Bento M Pepey B Vaudaux P Lew D Schrenzel J 《Journal of clinical microbiology》2003,41(1):254-260
A rapid procedure was developed for detection and identification of methicillin-resistant Staphylococcus aureus (MRSA) directly from sterile sites or mixed flora samples (e.g., nose or inguinal swabs). After a rapid conditioning of samples, the method consists of two main steps: (i) immunomagnetic enrichment in S. aureus and (ii) amplification-detection profile on DNA extracts using multiplex quantitative PCR (5'-exonuclease qPCR, TaqMan). The triplex qPCR assay measures simultaneously the following targets: (i) mecA gene, conferring methicillin resistance, common to both S. aureus and Staphylococcus epidermidis; (ii) femA gene from S. aureus; and (iii) femA gene from S. epidermidis. This quantitative approach allows discrimination of the origin of the measured mecA signal. qPCR data were calibrated using two reference strains (MRSA and methicillin-resistant S. epidermidis) processed in parallel to clinical samples. This 96-well format assay allowed analysis of 30 swab samples per run and detection of the presence of MRSA with exquisite sensitivity compared to optimal culture-based techniques. The complete protocol may provide results in less than 6 h (while standard procedure needs 2 to 3 days), thus allowing prompt and cost-effective implementation of contact precautions. 相似文献
18.
M. E. De Paepe Konstantinos Papadakis Brian D. Johnson Francois I. Luks 《Virchows Archiv : an international journal of pathology》1998,432(1):7-16
Tracheal occlusion in utero has been shown to cause accelerated fetal lung growth and is now being considered as a therapeutic
modality for pulmonary hypoplasia. We report the effects of tracheal ligation on the surfactant-producing type II pneumocyte
population. Three groups of fetal lambs underwent tracheal ligation of 2 weeks’, 4 weeks’ and 6 weeks’ duration, respectively,
and all were sacrificed at 136 days’ gestation (9 days pre-term). Nonoperated twins served as controls. The type II pneumocyte
population was studied morphometrically using a combination of anti-surfactant protein B immunohistochemistry and computer-assisted
stereologic morphometry at light and electron microscopic levels. Single-factor ANOVA was used for statistical analysis. Two
weeks of tracheal ligation resulted in doubling of the total lung volume as a result of airspace distension and, to lesser
extent, growth of the tissue compartment. With increasing duration of tracheal ligation, there was no additional lung growth.
However, more prolonged tracheal occlusion was found to result in significant reduction of the surfactant system, as reflected
in the marked decrease of total pneumocyte type II volume (3.14 cm3, 0.95 cm3, and 0.46 cm3, after 2, 4, and 6 weeks of ligation, compared with 5.96 cm3 for controls) and total pneumocyte type II number (13.9 × 109, 3.8 × 109, and 2.4 × 109, compared with 53.2 × 109 for controls). Ultrastructural analysis of the type II cells in obstructed lungs showed vacuolar degenerative changes that,
after 6 weeks of ligation, were apparently irreversible. In utero tracheal ligation causes fetal lung hyperplasia, but results
in reduction of and injury to the surfactant-producing cell population. Before tracheal occlusion can find widespread clinical
application, its pathophysiology needs to be further elucidated.
Received: 30 April 1997 / Accepted: 10 July 1997 相似文献
19.
Graaff Esther de; Rouillard Patricia; J.Willems Patrick; P.T.Smits Arie; Rousseau Francois; A.Oostra Ben 《Human molecular genetics》1995,4(1):45-49
The fragile X syndrome is the most frequent cause of inheritedmental retardation. The molecular mechanism of the disorderis based on the expansion of a CGG repeat in the 5' UTR of theFMR1 gene In the majority of fragile X patients. The instabilityof this CGG repeat containing region is not restricted to theCGG repeat Itself but expands to the flanking region as well.We describe four unrelated fragile X patients that are mosaicfor both a full mutation and a small deletion in the CGG repeatcontaining region. Sequence analysis of the regions surroundingthe deletions showed that both the (CGG)n repeat and some flankingsequences were missing in all four patients. The 5' breakpointsof the deletions were found to be located between 7553bp proximal to the CGG repeat. This suggests the presence ofa hot spot region for deletions in the CGG repeat region ofthe FMR1 gene and emphasizes the instability of this regionIn the presence of an expanded CGG repeat. 相似文献
20.
Functional mapping of the human globus pallidus: contrasting effect of stimulation in the internal and external pallidum in Parkinson's disease 总被引:4,自引:0,他引:4
Yelnik J Damier P Bejjani BP Francois C Gervais D Dormont D Arnulf I M Bonnet A Cornu P Pidoux B Agid Y 《Neuroscience》2000,101(1):77-87
Our objective was to elaborate a functional map of the globus pallidus by correlating the intrapallidal localization of quadripolar electrodes implanted in parkinsonian patients with the clinical effect of the stimulation of each contact. Five patients with L-DOPA-responsive Parkinson's disease presenting severe motor fluctuations and L-DOPA-induced dyskinesias were treated by continuous bilateral high-frequency stimulation of the globus pallidus. The effects of stimulation on parkinsonian disability were tested through each of the four stimulating contacts of each electrode. The anatomical localization of each of the stimulating contacts was determined by confronting the pre- and post-operative magnetic resonance imaging with the anatomical atlas of Schaltenbrand and Wharen.(34) The registration procedure comprised digitization of the atlas, the use of deformation tools to fit atlas sections with magnetic resonance imaging sections, and three-dimensional reconstruction of both the atlas and the magnetic resonance imaging sections. Analysis of the 32 stimulating contacts tested did not reveal a somatotopic organization in the pallidal region investigated but demonstrated that high-frequency stimulation had contrasting effects depending on whether it was applied to the external or the internal pallidum. Akinesia was improved by stimulation of the external pallidum but worsened by stimulation of the internal pallidum. In contrast, parkinsonian rigidity was improved by stimulation of either part of the pallidum. The areas in the internal pallidum where stimulation worsened akinesia were those in which stimulation reduced or suppressed L-DOPA-induced dyskinesias. Conversely, stimulation applied to the external pallidum induced dyskinesias. The fact that rigidity was improved by stimulation of the internal and external pallidum suggests that the neuronal bases of parkinsonian rigidity are different from those of akinesia and dyskinesias. The effect on akinesia and dyskinesias is in agreement with the current model of basal ganglia circuitry(10) if high-frequency stimulation activates rather than inhibits pallidal neurons, a possibility which is very likely since there are marked anatomical, biochemical and electrophysiological differences between the globus pallidus and the subthalamic nucleus.This study demonstrates that high-frequency stimulation of the globus pallidus in parkinsonian patients has contrasting effects depending on whether it is applied to the external or the internal part of this nucleus. The effect on akinesia and dyskinesias suggests that stimulation activates pallidal neurons, a result which challenges the generally accepted concept that high-frequency stimulation inactivates neurons in the region stimulated. 相似文献