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The following article discusses the experimental and clinical reasons for using absorbable synthetic explants in retinal surgery. We have carried out experimental studies with absorbable synthetic explants bandmade from absorbable sewing threads: PG910, PGA and PDS; proving that these explants are well tolerated by the organism. Their reabsorption time is from 45 days using PG910, to 8 months using PDS; these periods are sufficient for proper anatomical healing of the retina to take place. We present 13 cases of extraction of Teflon explants after retinal detachment surgery; in none of these cases did re-detachment of the retina occur. Consequently, this induced us to introduce absorbable synthetic explants into retinal detachment surgery, using absorbable threads, having previously carried out an experimental study on rabbits. We present 10 cases of retinal detachment operated on with PDS from 95 cases operated on using absorbable synthetic explants; 100% anatomical healing of the retina was achieved. We consider this type of explant to be the ideal material for retinal detachment healing, due to the fact that its period reabsorption, being longer than those of the other explants, allows a longer indentation period. 相似文献
134.
Eugenia Bruzzese Valeria Raia Eliana Ruberto Riccardo Scotto Antonietta Giannattasio Dario Bruzzese Maria Cristina Cavicchi Michela Francalanci Carla Colombo Nadia Faelli Valeria Daccò Giuseppe Magazzù Stefano Costa Vincenzina Lucidi Fabio Majo Alfredo Guarino 《Journal of cystic fibrosis》2018,17(3):375-382
Background
Intestinal dysbiosis has been described in Cystic Fibrosis (CF) and probiotics have been proposed to restore microbial composition. Aim of the study was to investigate the effects of Lactobacillus rhamnosus GG (LGG) on clinical outcomes in children with cystic fibrosis (CF).Methods
A multicentre, randomised double-blind, clinical trial was conducted in children with CF. After 6 months of baseline assessment, enrolled children (2 to 16 years of age) received Lactobacillus GG (6 × 109 CFU/day) or placebo for 12 months. Primary outcomes were proportion of subjects with at least one pulmonary exacerbation and hospitalisation over 12 months. Secondary endpoints were total number of exacerbations and hospitalisations, pulmonary function, and nutritional status.Results
Ninety-five patients were enrolled (51/95 female; median age of 103 ± 50 months). In a multivariate GEE logistic analysis, the odds of experiencing at least one exacerbation was not significantly different between the two groups, also after adjusting for the presence of different microbial organisms and for the number of pulmonary exacerbations within 6 months before randomisation (OR 0.83; 95% CI 0.38 to 1.82, p = 0.643). Similarly, LGG supplementation did not significantly affect the odds of hospitalisations (OR 1.67; 95% CI 0.75 to 3.72, p = 0.211). No significant difference was found for body mass index and FEV1.Conclusions
LGG supplementation had no effect on respiratory and nutritional outcomes in this large study population of children with CF under stringent randomised clinical trial conditions. Whether earlier interventions, larger doses, or different strains of probiotics may be effective is unknown. 相似文献135.
Ghiotto F Fais F Valetto A Albesiano E Hashimoto S Dono M Ikematsu H Allen SL Kolitz J Rai KR Nardini M Tramontano A Ferrarini M Chiorazzi N 《The Journal of clinical investigation》2004,113(7):1008-1016
Studies of B cell antigen receptors (BCRs) expressed by leukemic lymphocytes from patients with B cell chronic lymphocytic leukemia (B-CLL) suggest that B lymphocytes with some level of BCR structural restriction become transformed. While analyzing rearranged V(H)DJ(H) and V(L)J(L) genes of 25 non-IgM-producing B-CLL cases, we found five IgG(+) cases that display strikingly similar BCRs (use of the same H- and L-chain V gene segments with unique, shared heavy chain third complementarity-determining region [HCDR3] and light chain third complementarity-determining region [LCDR3] motifs). These H- and L-chain characteristics were not identified in other B-CLL cases or in normal B lymphocytes whose sequences are available in the public databases. Three-dimensional modeling studies suggest that these BCRs could bind the same antigenic epitope. The structural features of the B-CLL BCRs resemble those of mAb's reactive with carbohydrate determinants of bacterial capsules or viral coats and with certain autoantigens. These findings suggest that the B lymphocytes that gave rise to these IgG(+) B-CLL cells were selected for this unique BCR structure. This selection could have occurred because the precursors of the B-CLL cells were chosen for their antigen-binding capabilities by antigen(s) of restricted nature and structure, or because the precursors derived from a B cell subpopulation with limited BCR heterogeneity, or both. 相似文献
136.
Metabolic, humoral, and cellular responses in adult volunteers immunized with the genetically inactivated pertussis toxin mutant PT- 9K/129G 总被引:14,自引:0,他引:14 下载免费PDF全文
A Podda L Nencioni M T De Magistris A Di Tommaso P Bossù S Nuti P Pileri S Peppoloni M Bugnoli P Ruggiero 《The Journal of experimental medicine》1990,172(3):861-868
PT-9K/129G, a nontoxic mutant of pertussis toxin (PT) obtained by genetic manipulation, has been shown in animal models to be a promising candidate for new vaccines against whooping cough. To assess the safety and the immunogenicity of PT-9K/129G in humans, a pilot study has been performed in adult volunteers. The protein was found to be safe, capable of inducing high titers of toxin-neutralizing antibodies, and capable of generating immunological memory. In fact, vaccination caused an increase of cell-mediated response to PT, PT-9K/129G, S1 subunit, and B oligomer, indicating that memory T cells are induced by the vaccine. Since PT-9K/129G is mitogenic for T lymphocytes in vitro, it was investigated whether this activity is also present in vivo. No variation was observed in the proportion of T cells (CD3+), T helper cells (CD4+), and cytotoxic T cells (CD8+), as well as in that of other lymphoid populations, by FACS analysis. Interestingly, no thorough correlation was found between humoral and cellular responses. In one case, a very high cellular response was present in absence of detectable antibodies, suggesting that the antibody response, which is the only parameter measured in most clinical trials, may not give a complete picture of the response induced by a vaccine. 相似文献
137.
A 643-nucleotide-long fragment of rDNA gene was amplified by PCR in the nematode worm Caenorhabditis. When the experiments were performed by using samples fixed in formalin, artefacts were detected. While the size of the amplified fragment resulted unaffected, very striking differences were seen in the nucleotide sequences of the amplified fragments. Furthermore, in many cases, the PCR reaction failed completely. The results obtained might warn of potential problems, especially when the amount of DNA to be amplified scarce. 相似文献
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139.
Giorgia Querin Elisa DaRe Ilaria Martinelli Luca Bello Cinzia Bertolin Davide Pareyson Caterina Mariotti Elena Pegoraro Gianni Sorarù 《Neurological sciences》2016,37(11):1815-1821
The Spinal and Bulbar Muscular Atrophy Functional Rating Scale (SBMAFRS) is an established rating instrument used to assess the functional status of patients with Spinal and Bulbar Muscular Atrophy (SBMA). Our aim was to validate an Italian version of the scale. We administered the SBMAFRS to sixty SBMA patients during routine follow-up of clinical evaluations. To estimate the test stability, the scale was re-administered to a subset of 39 randomly selected patients after 8 weeks. The patients underwent clinical evaluation including 6-min walk. Psychometric analysis included reliability assessment and factorial analysis. To evaluate convergent validity, correlations between SBMAFRS items and muscular force assessed by manual testing, ALSFRS total score and subscales scores, and forced vital capacity, were performed. Internal consistency as measured by Cronbach’s alpha (total scale 0.85) was high. Test–retest reliability assessed by Spearman’s rho was also high. Principal component analysis with varimax rotation yielded a four-factor solution accounting for approximately 79 % of the variance. The scale total score and subscales score were strongly correlated with respective items and subscores of the ALSFRS, with respiratory function and with the 6-min walk test. In conclusion, we performed an Italian validation of the only existing disease-specific Functional Rating Scale for SBMA patients. This scale will be a useful tool not only in the clinical practice but also as an outcome measure in upcoming clinical trials. 相似文献
140.
Petra Schwingenschuh MD Tabish A. Saifee MRCP Petra Katschnig‐Winter MD MSc Antonella Macerollo MD Mariella Koegl‐Wallner MD Valeriu Culea MD Christine Ghadery MD PhD Edith Hofer PhD Tamara Pendl MD Stephan Seiler MD Ulrike Werner PhD Sebastian Franthal MD Natasha M. Maurits PhD Marina A. Tijssen MD PhD Reinhold Schmidt MD John C. Rothwell PhD Kailash P. Bhatia MD FRCP Mark J. Edwards FRCP PhD 《Movement disorders》2016,31(4):555-562