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81.
82.
Gómez-Román JJ Del Valle CE Zarrabeitia MT Martínez JC Goñi FZ Lera RM Cuevas J Val-Bernal JF 《Pathology international》2005,55(9):580-584
Bronchioloalveolar carcinoma is a distinctive subtype of pulmonary adenocarcinoma, without effective therapy, although there have recently been some attempts to use lung transplantation. However, a high post-transplantation local recurrence rate is described with some controversy regarding the possible involved mechanisms, the main possibilities being the lymphatic spread and aerosolization. Presented herein is a case of a bilateral lung transplantation for a bilateral and pneumonic form of non-mucinous bronchioloalveolar carcinoma in a 43-year-old woman. The histological analysis of mediastinal lymph nodes during surgery did not show neoplastic cells. Thirty-five months after transplantation several nodular opacities in donor lungs were detected. Three pulmonary wedge resections were performed showing a non-mucinous bronchioloalveolar carcinoma with the same histological characteristics as the primary. Again, the mediastinal lymph nodes were tumor free. A complete microsatellites molecular analysis was performed to compare the primary and recurrent carcinoma using capillary electrophoresis, showing that the recurrent tumor was generated in a recipient cellular clone. The absence of lymph node metastasis and the molecular evidence of the recipient origin of the neoplasm supports the contamination of the new lungs at the time of implantation as being the reason for the high incidence of recurrence after lung transplantation in this kind of disease. 相似文献
83.
Intranasal immunization with SAG1 and nontoxic mutant heat-labile enterotoxins protects mice against Toxoplasma gondii 总被引:19,自引:0,他引:19 下载免费PDF全文
Bonenfant C Dimier-Poisson I Velge-Roussel F Buzoni-Gatel D Del Giudice G Rappuoli R Bout D 《Infection and immunity》2001,69(3):1605-1612
Effective protection against intestinal pathogens requires both mucosal and systemic immune responses. Intranasal administration of antigens induces these responses but generally fails to trigger a strong protective immunity. Mucosal adjuvants can significantly enhance the immunogenicities of intranasally administered antigens. Cholera toxin (CT) and heat-labile enterotoxin (LT) are strong mucosal adjuvants with a variety of antigens. Moreover, the toxicities of CT and LT do not permit their use in humans. Two nontoxic mutant LTs, LTR72 and LTK63, were tested with Toxoplasma gondii SAG1 protein in intranasal vaccination of CBA/J mice. Vaccination with SAG1 plus LTR72 or LTK63 induced strong systemic (immunoglobulin G [IgG]) and mucosal (IgA) humoral responses. Splenocytes and mesenteric lymph node cells from mice immunized with LTR72 plus SAG1, but not those from mice immunized with LTK63 plus SAG1, responded to restimulation with a T. gondii lysate antigen in vitro. Gamma interferon and interleukin 2 (IL-2) production by splenocytes and IL-2 production by mesenteric lymph node cells were observed in vitro after antigen restimulation, underlying a Th1-like response. High-level protection as assessed by the decreased load of cerebral cysts after a challenge with the 76K strain of T. gondii was obtained in the group immunized with LTR72 plus SAG1 and LTK63 plus SAG1. They were as well protected as the mice immunized with the antigen plus native toxins. This is the first report showing protection against a parasite by using combinations of nontoxic mutant LTs and SAG1 antigen. These nontoxic mutant LTs are now attractive candidates for the development of mucosally delivered vaccines. 相似文献
84.
Paolo Sportoletti Beatrice Del Papa Mariangela De Ioanni Lorenzo Moretti Elisabetta Bonifacio Vania Lanterna Alain Bell Katia Fettucciari Eugenia Carnevali Tiziana Zei Franca Falzetti Massimo F Martelli Antonio Tabilio Mauro Di Ianni 《Biology of blood and marrow transplantation》2006,12(12):1250-1260
T-cell homeostasis is regulated by several molecules; among these, interleukin (IL)-7 plays an essential role in the survival and homeostatic proliferation of peripheral naive T cells. In a previous study, we investigated whether human mesenchymal stromal cells (MSCs) could be engineered with the IL-7 gene to produce functional level of this cytokine. In the present study, we analyzed the impact of different quantities of IL-7 produced by MSCs on the survival and proliferation of a negative immunoselected naive (CD3(+)/CD45RA(+)) T-cell population. Co-cultivation of peripheral naive T cells with MSCs producing low (16 pg/mL) or high (1000 pg/mL) IL-7 levels or in the presence of exogenous IL-7 (0.01 ng/mL and 100 ng/mL) maintained the CD3(+)/CD45RA(+) naive T-cell phenotype. Chemokine receptor CCR7(+) expression was also maintained among this T-cell population. Naive T-cell molecular characteristics were maintained as assessed by the Vbeta spectratyping complexity score, which showed the maintenance of a broad T-cell repertoire. No Th1 or Th2 differentiation was observed, as assessed by interferon-gamma or IL-4 accumulation. In contrast, only MSCs producing high amounts of IL-7 caused increased activation (CD25 31.2% +/- 12% vs 10% +/- 3.5%; P < .05), proliferation (CD71 17.8+/-7% vs 9.3%+/-3, P < .05), apoptosis (assessed by annexin V: 18.6% +/- 5% vs 14.9% +/- 2.6%; P > .05), and the phase S cell cycle (15% vs 6.9%, P > .05). Exogenous IL-7 exhibited no significant effect. In conclusion, we demonstrated that IL-7 produced by MSCs has a dose-independent effect on naive T-cell survival while exerting a dose-dependent effect on activation/proliferation. Due to the continuous production of IL-7 by engineered cells, our system is more efficacious than exogenous IL-7. 相似文献
85.
In vitro production of IgE by human peripheral blood mononuclear cells. I. Rate of IgE biosynthesis 下载免费PDF全文
S. Romagnani E. Maggi G. F. Del Prete R. Troncone M. Ricci 《Clinical and experimental immunology》1980,42(1):167-174
IgE protein and grass-specific IgE antibodies were detected in the supernatants of 7-day cultures of unstimulated and pokeweed mitogen (PWM) stimulated human blood mononuclear cells from non-atopic and grass pollen-sensitive individuals. Significant amounts of IgE protein were detected in culture supernatants of grass-sensitive individuals and, even at lower levels, in those of non-atopic subjects. In contrast, detectable amounts of grass-specific antibodies were found only in the culture supernatants of grass-sensitive subjects. The mean values of total and grass-specific IgE detected in the supernatants of unstimulated and PWM-stimulated cultures did not differ statistically. Time sequence studies showed that IgE concentrations, measured in the 7-day supernatants, were due to a continuous release from the cells of IgE quantities progressively decreasing up to days 7 or 8. Comparison of the IgE protein and IgE antibody found in the 7-day culture supernatants to those released from initial cell pellets by treatment with acid buffer or freezing and thawing, showed that the IgE detected in 7-day supernatants could result, in part, from the release of cytophilic IgE bound to basophil or other cell types and in part also from the release of preformed lymphocyte cytoplasmic IgE into the supernatant fluids during the course of culture. In most non-atopic subjects and in some grass-sensitive patients the preformed IgE accounted virtually for the total IgE detected in the 7-day culture supernatants. However, the increase of IgE above the levels measured in the initial cell pellets, which was found in most grass-sensitive subjects, clearly reflected newly synthesized IgE. Both cycloheximide and puromycin were capable of reducing significantly the IgE concentration in culture supernatants when it was greater than the amount found in the initial cell pellets. The treatment of cells with mitomycin C was also able to decrease significantly the amount of IgE released in the supernatant after day 3 of culture. 相似文献
86.
Esmer C Urraca N Carnevale A Del Castillo V 《American journal of medical genetics. Part A》2004,(2):162-166
Children with genetic diseases must be followed for long periods of time to seek new findings. Other patients require further check-ups and studies to be diagnosed. Some patients never return for medical care after the first consultation, which may have serious consequences. We reviewed 400 medical charts of patients with genetic disease to analyze overall attendance to the genetics clinic, investigate some of the causes of failure to seek medical advice, and determine the differences between those first seen as outpatients or as inpatients. The mean follow-up period was 8.3 months (range 0-79), and the average number of visits was 2.8 (range 1-16). Forty eight percent of the cases first seen as inpatients were evaluated only once and 14% twice; while 22 and 21% of the 300 cases first seen as outpatients attended once and twice, respectively (P = 0.0). Appointment keeping was apparently not affected by the presence or absence of diagnosis. Overall, 97 patients were discharged, 7 died, 55 continued on follow-up, 62 attended other hospital services-but not genetics-and 179 were completely lost to follow-up. Diagnosed patients were counseled more frequently than undiagnosed patients (62 vs. 5%); and 71% of the diagnosed patients first seen as outpatients but only 36% of undiagnosed cases first seen as inpatients were counseled, differences between these two groups were significant (P = 0.005). We conclude that keeping the patient with genetic disease on follow-up is a difficult task. New educational strategies must be planned to improve this worrisome situation. 相似文献
87.
Comparison of isolates of Neisseria gonorrhoeae causing meningitis and report of gonococcal meningitis in a patient with C8 deficiency. 总被引:1,自引:0,他引:1 下载免费PDF全文
C Del Rio D S Stephens J S Knapp R J Rice W O Schalla 《Journal of clinical microbiology》1989,27(5):1045-1049
We studied a previously healthy 20-year-old woman who presented with gonococcal meningitis. The gonococcal isolate, HT-1, was prototrophic by auxotyping, was protein I serovar IB-1, and agglutinated with wheat germ lectin. This isolate differed from the proline-requiring, serovar IA-1 and IB-4, wheat germ-agglutination-negative gonococcal isolates recovered from three patients during a recent outbreak of gonococcal meningitis in Philadelphia. HT-1 was killed by normal pooled human sera (greater than or equal to 98% at 30 min) but not effectively killed by the convalescent-phase sera of the patient (greater than 30% survival at 30 min). Similar results were obtained when mucosal and cerebrospinal fluid isolates from a Philadelphia patient were exposed to these sera, but mucosal and blood isolates from another Philadelphia case showed increased resistance to killing by normal pooled human sera. Further characterization revealed multiple differences in outer membrane and cellular proteins and lipopolysaccharide between case isolates. Absence of the L8 lipopolysaccharide epitope was noted for all isolates. Sera of our patient were found to have low total hemolytic complement (CH100 = 21 U/ml; normal = 55 to 100 U/ml) due to deficiency of C8 (C8 less than 1,000 CH50 U/ml; normal = greater than or equal to 16,000 CH50 U/ml). This is the first reported case of gonococcal meningitis occurring in a patient with a terminal-complement deficiency. Gonococcal meningitis is a rare complication of gonococcal bacteremia. Both defects in host defenses (e.g., terminal-complement deficiency) and organisms with unusual virulence appear to contribute to the pathogenesis of this complication of gonococcal bacteremia. 相似文献
88.
The first case of human subcutaneous dirofilariasis in the Marche region (Central Italy) is described. It was caused by Dirofilaria repens and localised in the abdominal wall of a 23 years old university student from Pesaro. The presence of many histological sections of the nematode in strong regression, suggests that the death of the parasite occurred inside the nodule many months before the surgical intervention. 相似文献
89.
Direct induction of human B-cell differentiation by recombinant interleukin-2. 总被引:5,自引:0,他引:5 下载免费PDF全文
S Romagnani G Del Prete M G Giudizi R Biagiotti F Almerigogna A Tiri A Alessi M Mazzetti M Ricci 《Immunology》1986,58(1):31-35
Recombinant interleukin-2 (rIL-2) induced highly purified human tonsillar B cells to differentiate into immunoglobulin (Ig)-producing cells in vitro. The B-cell response was not due to rIL-2-contaminating substances, but reflected the activity of IL-2 itself, since it was inhibited by addition to the cultures of anti-TAC monoclonal antibody. The rIL-2-induced B-cell response was apparently not mediated by factors released by residual T cells present in B-cell suspensions at undetectable levels, since supernatants (SN) from unstimulated autologous T cells cultured at concentrations even much higher than those possibly contaminating B-cell suspensions did not induce any detectable Ig production. In addition, the Ig production by B cells cultured with SN prepared from high numbers of autologous T cells stimulated with rIL-2, as well as from allo-activated or mitogen-stimulated T cells, was of the same magnitude as the Ig production resulting from direct addition of rIL-2 concentrations comparable with those present in the supernatants. After centrifugation on Percoll density gradients, most of the tonsillar B cells responsive to rIL-2 were recovered in the lower density cell fraction containing a number of larger activated B cells. Moreover, B-cell enriched suspensions from peripheral blood (PB) (which usually contains a lower number of in vivo activated B cells than tonsil) showed poor or no response to rIL-2 alone, but displayed significant Ig production when rIL-2 was added to the cultures in the presence of Staphylococcus aureus Cowan I (SAC) bacteria.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
90.
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