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31.
Domenico Schiavino Eleonora Nucera Emanuela Pollastrini Tiziana De Pasquale Alessandro Buonomo Francesco Bartolozzi Carla Lombardo Chiara Roncallo Giampiero Patriarca 《Annals of allergy, asthma & immunology》2004,92(4):409-413
BACKGROUND: Hymenoptera venom hypersensitivity is an epidemiologically important problem. The only effective treatment in the management of venom-allergic patients with a history of generalized reactions to insect sting is specific immunotherapy. OBJECTIVE: To demonstrate safety and effectiveness of a modified ultrarush desensitization protocol in venom-allergic patients. METHODS: Fifty-seven patients with Hymenoptera venom allergy underwent a specific 1-day ultrarush desensitization by the subcutaneous route, reaching the cumulative dose of 101.1 microg in 2.5 hours. The maintenance dose (100 microg) was administered after 15 days and thereafter once a month. Patients were followed up for a year. Antihistamines were withheld for 15 days before and during desensitization to not underestimate the incidence of adverse effects. RESULTS: All patients but I completed the ultrarush desensitization. (This patient discontinued the treatment because of a hypertensive crisis not related to the desensitization.) The treatment caused a rapid variation of immunological parameters (IgE, IgG4) since the 15th day. After the desensitization, skin prick test results became negative in 15 patients (27%, decrease of 3.5 log), whereas they decreased in 14 patients (25%, decrease of 1 log). Sixty-four percent showed no adverse effects. Only 7% had a mild systemic reaction. CONCLUSIONS: Ultrarush desensitization is an effective and safe therapy in the management of patients with Hymenoptera venom allergy. In fact, it provides a faster tolerance, without significant differences regarding incidence of severe adverse effects, compared with traditional and rush protocols. It can be adopted for all patients, even children and teenagers. 相似文献
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33.
V Júnior Haddad H A Miot L D Bartoli A de Chiara Cardoso R M Pires de Camargo 《Medical mycology》2002,40(4):425-427
Localized lymphatic sporotrichosis generally develops after the fungus Sporothrix schenckii is traumatically introduced into skin or mucosa by contaminated plant material. An 18-year-old male fisherman was injured by spines of the dorsal fin of a fish on the left third finger. The lesion became ulcerated, edematous and suppurative and did not respond to tetracycline and cephalexin. Fifteen days after the accident, a nodular lymphangitic pattern of swelling was observed. Histopathological findings and an intradermal test were suggestive of sporotrichosis and mycological cultures confirmed the diagnosis. The lesions resolved after oral treatment with potassium iodide. Sporotrichosis is a common subcutaneous mycosis in Brazil, and there is a previous report in the literature of this disease being acquired via trauma involving fish spines. 相似文献
34.
Ultrastructural analysis of pancreatic acinar cells from mice fed on genetically modified soybean 下载免费PDF全文
Malatesta M Caporaloni C Rossi L Battistelli S Rocchi MB Tonucci F Gazzanelli G 《Journal of anatomy》2002,201(5):409-415
No direct evidence that genetically modified (GM) food may represent a possible danger for health has been reported so far; however, the scientific literature in this field is quite poor. Therefore, we investigated the possible effects of a diet containing GM soybean on mouse exocrine pancreas by means of ultrastructural, morphometrical and immunocytochemical analyses. Our observations demonstrate that, although no structural modification occurs in pancreatic acinar cells of mice fed on GM soybean, quantitative changes of some cellular constituents take place in comparison to control animals. In particular, a diet containing significant amount of GM food seems to influence the zymogen synthesis and processing. 相似文献
35.
Crotti D D'Annibale ML Ubaldi M Fonzo G Medori MC 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2002,10(4):213-219
During 2001 we analyzed 1730 pharyngeal swabs for S. pyogenes (SGA): 1142 children (0-10 years old), 132 adolescent subjects (11-17 years old), and 456 adults (18 or more years old). 994 subjects (664 children, 85 adolescent ones, 245 adults) had acute pharyngotonsillitis. In this last group we observed 321 positivities (32.3 %) for SGA: 40.4 % among children, 24.7 % among adolescent people, 13.1 % among adults. The pharyngotonsillitis prevailed during winter and spring. The resistances (R) towards erythromycin were 27.7 % (89 cases), and among children 30.6 % (82 cases), towards clyndamicin 15.3 % (49 cases, and 17.2 %, 46 cases, among children), towards rokytamicin 11.8 % (38 cases, and 13.1 %, 35 cases, among children). These were the phenotypes of R to erythromycin: 25.8 % M-phenotype, 19.1 % inducible (iMLS), 55.1 % constitutive (cMLS); among children respectively 25.6 %, 18.3 % and 53.7 %. Increased resistances towards 16-C macrolides, increased resistances of cMLS to erythromycin, and the persistence of R to 14-C macrolides around 30 % are discussed. 相似文献
36.
Simona Di Terlizzi Elisabetta Zino Benedetta Mazzi Chiara Magnani Cristina Tresoldi Serena Kimi Perna Marco Bregni Silvano Rossini Fabio Ciceri Claudio Bordignon Chiara Bonini Katharina Fleischhauer 《Biology of blood and marrow transplantation》2006,12(1):95-101
Minor histocompatibility antigens (mHags) HA-1 and HA-2 are encoded by biallelic loci, with immunogenic variants, HA-1H and HA-2V, which induce strong HLA-A2-restricted alloreactive T-cell responses, and nonimmunogenic counterparts, HA-1R and HA-2M, which represent functional null alleles that are poorly presented by HLA class I molecules. HA-1 and HA-2 are potential targets of selective graft-versus-leukemia and graft-versus-tumor reactivity after allogeneic hematopoietic stem cell transplantation (HSCT); however, these applications are restricted to a limited number of patients. Here, we show that a far more frequent application of HA-1 and HA-2 disparity relies on their use as markers for the state of host chimerism after allogeneic HSCT. We have determined allelic frequencies of 29.3% and 70.7% for HA-1H and HA-1R, respectively, and of 83.7% and 16.3% for HA-2V and HA-2M, respectively, in >200 healthy individuals from northern Italy. Similar frequencies were observed in nearly 100 patients affected by hematologic malignancies or solid tumors, thus showing that HA-1 and HA-2 variability are not associated with the presence of cancer. On the basis of these data, we predict that HA-1 and HA-2 can be used in 32.8% and 23.5% of Italian transplant patients, respectively, as markers for the state of host chimerism, whereas exploitation of disparity for these mHags for targeted immunotherapy will be possible in 10.7% and 1.1% of Italian patients, respectively. Retrospective HA-2 typing of bone marrow aspirates obtained from a patient during complete remission or recurrence of acute myeloid leukemia after haploidentical HSCT showed the feasibility of using HA-2 as a surrogate marker for disease monitoring. Because of an apparent north-south gradient for HA-1 allelic frequencies, with higher frequencies for the HA-1H variant reported in white populations from Southern Europe as compared with Northern Europe and North America, the diagnostic applicability of HA-1 disparity will be slightly more frequent in transplant patients from the north. Taken together, our data show that determination of HA-1 and HA-2 variability can be an important parameter for the selection of allogeneic stem cell donors, in particular for patients affected by hematologic malignancies without a tumor-specific molecular marker. 相似文献
37.
38.
Ca2+ is the primary regulator of force generation by cross-bridges in striated muscle activation and relaxation. Relaxation is as necessary as contraction and, while the kinetics of Ca2+-induced force development have been investigated extensively, those of force relaxation have been both studied and understood less well. Knowledge of the molecular mechanisms underlying relaxation kinetics is of special importance for understanding diastolic function and dysfunction of the heart. A number of experimental models, from whole muscle organs and intact muscle fibres down to single myofibrils, have been used to explore the cascade of kinetic events leading to mechanical relaxation. By using isolated myofibrils and fast solution switching techniques we can distinguish the sarcomeric mechanisms of relaxation from those of myoplasmic Ca2+ removal. There is strong evidence that cross-bridge mechanics and kinetics are major determinants of the time course of striated muscle relaxation whilst thin filament inactivation kinetics and cooperative activation of thin filament by cycling, force-generating cross-bridges do not significantly limit the relaxation rate. Results in myofibrils can be explained well by a simple two-state model of the cross-bridge cycle in which the apparent rate of the force generating transition is modulated by fast, Ca2+-dependent equilibration between off- and on-states of actin. Inter-sarcomere dynamics during the final rapid phase of full force relaxation are responsible for deviations from this simple model. 相似文献
39.
Zei G Lisa A Fiorani O Magri C Quintana-Murci L Semino O Santachiara-Benerecetti AS 《European journal of human genetics : EJHG》2003,11(10):802-807
A total of 202 Sardinian male subjects were examined for 13 biallelic stable markers, the complex 49a,f/TaqI system and three microsatellites of the Y chromosome in order to investigate, through surname analysis, on a possible territorial heterogeneity inside the island. The study of geographical distribution and linguistic derivation of Sardinian surnames allow us to discover their 'probable place of origin' and reconstruct ancient genetic isolates which borders are, today, no more recognizable. The molecular analysis revealed that about 90% of the Sardinian Y chromosomes fell into haplogroups E-M35, G-M201, I-M26, J-12f2 and R-M269. In contrast with the territorial homogeneity of these haplogroups, when the individuals were distributed according to their birthplace, a significant difference between the three historically and culturally distinct geographical areas into which Sardinia can be subdivided was observed when the individuals were distributed according to the ancestral location of surnames. In particular, the major contribution to this heterogeneity is due to the 'Sardinian-specific' haplogroup I-M26 (almost completely associated with the 49a,f-Ht12/12f2-10Kb/YCAIIa-21/YCAIIb-11 compound haplotype), which shows both a significantly higher incidence in the central-eastern (archaic) area and a significantly lower frequency in the northern area. The results of this study agree with the hypothesis that the ancestral homeland of this specific subset of haplogroup I is the mountainous central-eastern area of Sardinia, where the population underwent a long history of isolation since ancient times, and highlight the informative power of the surname analysis. 相似文献
40.
Patrizia Sadocco Chiara Bulli Graziano Elegir Alberto Seves Ezio Martuscelli 《Macromolecular chemistry and physics.》1993,194(10):2675-2686
The biodegradability of solution-cast films of poly(D (–)-3-hydroxybutyrate) (PHB) blended with the melt-compatible component atactic poly(epichlorohydrin) (aPECH) was investigated. A bacterium which produced extracellular enzymes that degraded PHB even when blended with aPECH was isolated, and tentatively designated as Aureobacterium saperdae. The growth rate of A. saperdae decreased with increasing aPECH content in the blend, up to films containing 60 wt.-% aPECH, at which composition growth was completely inhibited. The decrease in the bacterial growth rate could be due to the dilution of PHB molecules on the blend film surface caused by the presence of aPECH molecules. At the stationary phase of bacterial growth the percentage of weight loss of blend films decreased with increasing aPECH fraction, which was probably due to the lower accessibility of PHB when blended with aPECH. During the bacterial growth only PHB was metabolized, whereas neither degradation nor abiotic release of aPECH was detected for blend films. 相似文献