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21.
In this paper we will review the results obtained during the last 2 years with the aponeurotic galea and subgalea for vermillion lip augmentation. The survey was carried out on 42 patients who displayed either an absence of or reduction in the vermillion of one or both lips or a senile lip. In all cases the surgical procedure introduced aponeurotic galea and subgalea in the space found between the orbicular lip muscle and the vestibular mucus, just behind the vermillion. All the operations were performed under local anaesthetic. The size of the aponeurotic galea fragment removed varied in length between 10 and 12 cms. and in width between 1 and 2 cms., using the following parameters for its dimensions: the previous volume of the lips, and the distance between the two buccal commissures when in the “smile position.” 相似文献
22.
The goal of IMRT is to achieve an isodose distribution conformed to the tumor while avoiding the organs at risk. For these tasks several gantry angles are selected, each one containing a series of different leaf configurations for the multileaf collimator (MLC) (segments). Verifying the relative distributions as well as the absolute doses is an important step for quality assurance issues. We have observed that an accurate modeling of the transmission of the primary x-ray fluence through the jaws and MLC as well as the head scatter is crucial for a precise calculation of relative doses and monitor units. Also, an inaccurate calculation of the output factor for small size segments can lead to important differences in the absolute dose for points under these segments. Incorrect models could lead to systematic errors of around 5% to 10% in the calculated monitor units and a shift in the isodose curves. 相似文献
23.
Evolution of foot-and-mouth disease virus 总被引:28,自引:0,他引:28
Domingo E Escarmís C Baranowski E Ruiz-Jarabo CM Carrillo E Núñez JI Sobrino F 《Virus research》2003,91(1):47-63
Foot-and-mouth disease virus evolution is strongly influenced by high mutation rates and a quasispecies dynamics. Mutant swarms are subjected to positive selection, negative selection and random drift of genomes. Adaptation is the result of selective amplification of subpopulations of genomes. The extent of adaptation to a given environment is quantified by a relative fitness value. Fitness values depend on the virus and its physical and biological environment. Generally, infections involving large population passages result in fitness gain and population bottlenecks lead to fitness loss. Very different types of mutations tend to accumulate in the foot-and-mouth disease virus (FMDV) genome depending on the virus population size during replication. Quasispecies dynamics predict higher probability of success of antiviral strategies based on multivalent vaccines and combination therapy, and this has been supported by clinical and veterinary practice. Quasispecies suggest also new antiviral strategies based on virus entry into error catastrophe, and such procedures are under investigation. Studies with FMDV have contributed to the understanding of quasispecies dynamics and some of its biological implications. 相似文献
24.
25.
Ignacio Gonzalez-Gomez Ilkka Mononen Nora Heisterkamp John Groffen Vesa Kaartinen 《The American journal of pathology》1998,153(4):1293-1300
Aspartylglycosaminuria (AGU) is one of the most common lysosomal storage disorders in humans. A mouse model for AGU has been recently generated through targeted disruption of the glycosylasparaginase gene, and at a young age the glycosyl asparaginase-deficient mice demonstrated many pathological changes found in human AGU patients (Kaartinen V, Mononen I, Voncken J-W, Gonzalez-Gomez I, Heisterkamp N, Groffen J: A mouse model for aspartylglycosaminuria. Nat Med 1996, 2:1375–1378). Our current findings demonstrate that after the age of 10 months, the general condition of null mutant mice gradually deteriorated. They suffered from a progressive motoric impairment and impaired bladder function and died prematurely. A widespread lysosomal hypertrophy in the central nervous system was detected. This neuronal vacuolation was particularly severe in the lateral thalamic nuclei, medullary reticular nuclei, vestibular nuclei, inferior olivary complex, and deep cerebellar nuclei. The oldest animals (20 months old) displayed a clear neuronal loss and gliosis, particularly in those regions, where the most severe vacuolation was found. The severe ataxic gait of the older mice was likely due to the dramatic loss of Purkinje cells, intensive astrogliosis and vacuolation of neurons in the deep cerebellar nuclei, and the severe vacuolation of the cells in vestibular and cochlear nuclei. The impaired bladder function and subsequent hydronephrosis were secondary to involvement of the central nervous system. These findings demonstrate that the glycosylasparaginase-deficient mice share many neuropathological features with human AGU patients, providing a suitable animal model to test therapeutic strategies in the treatment of the central nervous system effects in AGU. 相似文献
26.
Coxsackievirus B3-Induced Myocarditis : Perforin Exacerbates Disease, But Plays No Detectable Role in Virus Clearance 总被引:8,自引:3,他引:8
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John R. Gebhard Christopher M. Perry Stephanie Harkins Thomas Lane Ignacio Mena Valrie C. Asensio Iain L. Campbell J. Lindsay Whitton 《The American journal of pathology》1998,153(2):417-428
Viral myocarditis is remarkably common, being detected in approximately 1% of unselected asymptomatic individuals. Many cases are attributable to enteroviral infection, and in particular to coxsackievirus B3. The underlying pathogenesis is controversial, but most studies admit the important immunopathological role of infiltrating CD8+ (cytotoxic) T lymphocytes (CTLs). We have previously shown that CTLs play conflicting roles in coxsackievirus B (CVB) myocarditis; they assist in controlling virus replication, but also are instrumental in causing the extensive inflammatory disease, which often results in severe myocardial scarring. A role for perforin, the major CTL cytolytic protein, in CVB myocarditis has been suggested, but never proven. In the present study we use perforin knockout (PKO) mice to show that perforin plays a major role in CVB infection; in broad terms, perforin is important in immunopathology, but not in CVB clearance. For example, PKO mice are better able to withstand a normally lethal dose of CVB (100% survival of PKO mice compared with 90% death in +/+ littermates). In addition, PKO mice given a nonlethal dose of CVB develop only a mild myocarditis, whereas their perforin+ littermates have extensive myocardial lesions. The myocarditis in PKO mice resolves more quickly, and these mice show minimal histological sequelae; in contrast, late in disease the perforin+ mice develop severe myocardial fibrosis. PKO mice, despite lacking this major CTL effector function, can control the infection and eradicate the virus; growth kinetics and peak CVB titers are indistinguishable in PKO and perforin+ mice. Therefore, the immunopathological and antiviral effects of CTLs can be uncoupled by ablation of perforin; this offers a promising target for therapy of myocarditis. Furthermore, we evaluate the possible roles of apoptosis, and of chemokine expression, in CVB infection. In perforin+ mice, apoptotic cells are detected within the inflammatory infiltrate, whereas in their PKO counterparts, apoptotic myocyte nuclei are seen. Chemokine expression in both PKO and perforin+ mice precedes and parallels the course of myocarditis. Several chemokines are detectable earlier in PKO mice than in perforin+ mice, but PKO mice show reduced peak levels, and chemokine expression decays sooner. In particular, MIP-1α expression is barely detectable at any time point in PKO mice, but it is readily identified in perforin+ animals, peaking just before the time of maximal myocarditis; this is particularly interesting, given that MIP-1α knockout mice are resistant to CVB myocarditis, but remain able to control viral infection. Thus, the chemokine pathway offers a second route of intervention to diminish myocarditis and its sequelae, while permitting the host to eradicate the virus. 相似文献
27.
Campos B Díez O Odefrey F Domènech M Moncoutier V Martínez-Ferrandis JI Osorio A Balmaña J Barroso A Armengod ME Benítez J Alonso C Stoppa-Lyonnet D Goldgar D Baiget M 《Human mutation》2003,21(4):452-452
A frame-shift 9254del5 mutation was independently identified in 12 families, eleven of them with Spanish ancestors, in a BRCA2 screening performed in 841 breast and/or ovarian cancer families and in 339 women with breast cancer diagnosed before the age of 40 at different centers in France and Spain. We sought to analyze in detail the haplotype and founder effects of the 9254del5 and to estimate the time of origin of the mutation. Eight polymorphic microsatellite markers and two BRCA2 polymorphisms were used for the haplotype analyses. The markers were located flanking the BRCA2 gene spanning a region of 6.1 cM. Our results suggest that these families shared a common ancestry with BRCA2 9254del5, which is a founder mutation originating in the Northeast Spanish, with an estimated age of 92 (95% CI 56-141) generations. 相似文献
28.
Gaforio JJ Ortega E Algarra I Serrano MJ Alvarez de Cienfuegos G 《Clinical and diagnostic laboratory immunology》2002,9(6):1282-1294
The participation of NK cells in the activation of splenic macrophages or in resistance to systemic candidiasis is still a matter of debate. We had previously reported that there is a correlation between natural killer cell activation and resistance to systemic candidiasis. In those experiments we had used tilorone to boost NK cell activity in mice. Here we show a mechanism elicited by tilorone in splenic macrophages which could explain their effect on mouse survival during acute disseminated Candida albicans infection. The results demonstrate that tilorone treatment elicits, by a direct effect, the production of proinflammatory cytokines (interleukin-6 [IL-6], tumor necrosis factor alpha [TNF-alpha], and IL-12) by splenic macrophages. In addition, it increases the capacity of splenic macrophages to phagocytize C. albicans through activation of NK cells. We also demonstrate that the presence of NK cells is essential for maintaining a basal level of phagocytic activity, which characterizes splenic macrophages of na?ve control mice. The results demonstrate that it is possible to identify two phenotypically and functionally peculiar cell populations among splenic macrophages: (i). cells of the "stimulator/secretor phenotype," which show high levels of major histocompatibility complex (MHC) class II surface expression, are poorly phagocytic, and synthesize the proinflammatory cytokines IL-6, TNF-alpha, and IL-12, and (ii). cells of the "phagocytic phenotype," which express low levels of MHC class II molecules, are highly phagocytic, and do not secrete proinflammatory cytokines. 相似文献
29.
Ignacio Algarra Matías Pérez Jose Juan Gaforio Fernando Gasca Federico Garrido 《Clinical & experimental metastasis》1994,12(1):31-36
The role of different tilorone analogs in the abrogation of the metastatic spread of H-2 positive and H-2 negative tumor clones was studied. Pre-treatment of BALB/c mice with RMI 10,874DA compound completely abolished lung colonization of an H-2 negative (GR9.B9) MCA-induced fibrosarcoma clone in an experimental metastasis assay. This effect was also evident when clones were treated with other tilorone analogs (R11,567DA or R11,513DA). Other H-2 positive and H-2 negative chemically induced fibrosarcoma clones were also tested. The effect was not due to direct toxicity of the tilorone analog on tumor cells, but instead was dependent on NK cells; this was suggested by the finding that treatment of mice with anti-asialo GM1 abrogated the effect of the tilorone analog (RMI 10,874DA compound). Interestingly, the inhibition of lung colonization after intravenous injection was again observed regardless of the H-2 phenotype of the tumor clones, and H-2+ and H-2– clones were similarly inhibited.In vitro assays of NK sensitivity of tumor clones showed that lysis varied depending on the H-2 phenotype of tumor clones, indicating an absence of correlation betweenin vivo andin vitro results. 相似文献
30.
Susana Camacho Maria Del Valle Ostos José Ignacio Llorente Ana Sanz Manuel García Alberto Domezain Ramón Carmona 《Anatomical record (Hoboken, N.J. : 2007)》2007,290(9):1178-1189
Ampullary organs of Acipenser naccarii sturgeons were examined by optical and electronic microscopy (transmission electron microscopy and scanning electron microscopy) from hatching until 1 month later when the juvenile phase is completely established. It was observed that, when A. naccarii begins to feed actively, the ultrastructural characteristics of ampullary organs already correspond to those of adult animals. These organs may, therefore, be functional and, together with taste buds, facilitate food search after exhaustion of yolk sac food reserves. Mature ampullary organs of A. naccarii are formed by an ampulla that communicates with the exterior by means of a short channel. These ampullae correspond to the sensory portion of these receptors and are formed by two cell types: receptor cells and support cells. Receptor cells present a kinocilium on their free surface and establish ribbon synapses with axon nerve endings that arise from the underlying conjunctive tissue. Support cells enclose receptor cells, bear stereocilia and occasional cilia, and are of a secretory nature. The mucus associated with ampullary organs mainly comprises neutral mucopolysaccharides, whereas mucopolysaccharides are usually acid in other fish groups. Anat Rec, 290:1178–1189, 2007. © 2007 Wiley‐Liss, Inc. 相似文献