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71.
Loxosceles adelaida spiders (Araneae, Sicariidae) are found near and inside the caves in the Parque Estadual Turistico do Alto Ribeira (PETAR), Sao Paulo, Brazil, which are visited by thousands of tourists every year. Several Loxosceles species are a public health problem in many regions of the world, by causing severe dermonecrosis and/or complement dependent haemolysis upon envenomation. The aim of this study was to characterize the biochemical and biological properties of L. adelaida venom and evaluate the toxic potential of envenomation by this non-synanthropic Loxosceles species. The biological activities of the L. adelaida venom was compared to that of Loxosceles gaucho, a synanthropic species of medical importance in Brazil. L. adelaida venom showed a similar potential to induce haemolysis, dermonecrosis and lethality as L. gaucho venom. L. adelaida crude venom was purified, yielding a 31 kDa component endowed with haemolytic and dermonecrotic activities. In conclusion, we show here that the troglophile Loxosceles species, L. adelaida, commonly found in the complex of caves from PETAR, is potentially able to cause envenomation with the same gravity of those produced by synanthropic species.  相似文献   
72.
We conducted a meta-analysis of randomized controlled clinical trials on steroid treatment for multiple sclerosis and optic neuritis. Of the 25 trials comparing steroids and controls without steroid treatment that we identified 12 were selected for this review. A meta-analysis was conducted to calculate the overall odds ratio across the studies for the numbers of patients without functional improvement and with new relapses. The trials included a total of 1714 patients: 998 with multiple sclerosis and 716 with optic neuritis. Any type of corticosteroids or adrenocorticotropic hormone (ACTH) treatment was considered, as was any dosage, route of administration, and length of treatment. Main outcome measures were: (a) number of multiple sclerosis patients who did not improve by at least one point on the EDSS or equivalent scale, or number of optic neuritis patients without complete recovery of visual acuity at 8 or 30 days and at longer follow-up; (b) number of multiple sclerosis patients with at least one new relapse, or number of optic neuritis patients in whom definite multiple sclerosis was diagnosed at longer follow-up. We found that corticosteroids or ACTH produced a significant improvement in disability or visual acuity at 30 days (odds ratio 0.49; 95 % CI 0.37–0.64). The improvement was not statistically significant at longer follow-up (0.85; 95 % CI 0.67–1.09). The treatment did not significantly reduce the number of patients with relapses (0.74; 95 % CI 0.54–1.01). Both low and high doses were effective for 30-day improvement, but only high-dose and short-term therapy were factors that identified subgroups with some reduction in the risk of new relapse. However, the power of the statistical analysis to detect a reliable difference in the subgroups was low. Steroid treatment is therefore effective in accelerating short-term recovery in patients with multiple sclerosis or optic neuritis. Whether steroids are also effective in reducing the risk of relapse, and the optimal dose and length of treatment must still be determined. Received: 5 August 1999, Received in revised form: 29 December 1999, Accepted: 22 January 2000  相似文献   
73.
BACKGROUND: Recently we demonstrated an increased 2,3-diphosphoglycerate (2,3-DPG) erythrocyte concentration in rat pups subjected to nucleotide-enriched artificial feeding. DESIGN: The present study was carried out to test the hypothesis that a possible increase in 2,3-DPG concentration can also be obtained in human neonates who are fed nucleotide-enriched formula. Preterm neonates born or referred to the neonatal intensive care unit of the G. Gaslini Hospital, Genoa University, with a gestational age >30 weeks and <37 weeks were enrolled in our randomized trial. Recruitment took place within 48-72 hours from birth. Only newborns of mothers deciding not to breast-feed were eligible to be randomized for the supplemented group (FN) or non-supplemented group (RF). Breast-fed newborns were considered the control group (C). The study window (for supplementation and blood samples) was restricted to the first two weeks following birth (from the 2nd (t1) to the 16th (t2) day of life). At the end of our study, only 21 neonates were eligible for statistical analysis. RESULTS: The stimulating action of dietary nucleotides on 2,3-DPG concentration failed to be demonstrated; increases in 2,3-DPG concentration that were observed in newborns fed with nucleotide supplemented formula (FN) were comparable to those observed in newborns fed with regular formula (RF) and breast-fed newborns. CONCLUSIONS: The EC recommendation for the amount of nucleotides allowed in formula milk does not seem to be high enough to have positive effects on 2,3-DPG synthesis. Whether this possible 'pharmacological' effect can be achieved by a higher intake of ingested nucleotides and/or a change in the proportions of single nucleotides contained in milk formulas remain interesting end points to be elucidated.  相似文献   
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Despite the existence of an effective live-attenuated vaccine, measles can appear in vaccinated individuals. We investigated breakthrough measles cases identified during our surveillance activities within the measles/rubella surveillance network (MoRoNet) in Milan and surrounding areas (Northern Italy). Between 2017 and 2021, we confirmed measles virus (genotypes B3 or D8) infections in 653 patients and 51 of these (7.8%) were vaccinees. Among vaccinated individuals whose serum was available, a secondary failure was evidenced in 69.4% (25/36) of cases while 11 patients (30.6%) were non-responders. Non-responders were more frequently hospitalized and had significantly lower Ct values in both respiratory and urine samples. Median age and time since the last immunization were similar in the two groups. Importantly, we identified onward transmissions from vaccine failure cases. Vaccinees were involved in 20 outbreaks, in 10 of them they were able to transmit the virus, and in 8 of them, they were the index case. Comparing viral hemagglutinin sequences from vaccinated and non-vaccinated subjects did not show a specific mutation pattern. These results suggest that vaccination failure was likely due to the poor immune response of single individuals and highlights the importance of identifying breakthrough cases and characterizing their clinical and virologic profiles.  相似文献   
79.
Simple SummaryGlioblastoma is an aggressive brain tumor with a dismal prognosis. In a minority of cases, it presents with multiple lesions already at the time of diagnosis, affecting patients’ survival and treatment. Our retrospective study aims to increase the current understanding and define a treatment for this sub-entity, to improve patient survival. Chemoradiotherapy is a also safe and efficacy treatment in patients with multiple lesions. Survival advantages from extensive resection remain unclear.AbstractGlioblastomas with multiple foci at presentation (mGBMs) account for 2–35% of all GBMs. mGBMs have limited existing data and no standardized treatment. This study aims to determine their incidence, demographic and clinical features, outcome, and prognostic factors in terms of overall survival. We performed a monocentric retrospective study, reviewing patients treated at the Istituto Oncologico Veneto. Inclusion criteria were: new diagnosis of GBM and presence of multiple lesions on pre-treatment MRI. ECOG PS was used to evaluate clinical condition, RANO criteria for radiological assessment, and CTCAE v5.0 for treatment-related adverse events. The incidence of newly diagnosed mGBM was 7.2% and the study population consisted of 98 patients. Median age was 63 years, M:F ratio of 1.8:1, and a surgical approach was undertaken in 73 patients (mostly partial resection). MGMT was methylated in 47.5%, and 82 patients received active oncological treatment (65.9% radiotherapy plus temozolomide (RT + TMZ)). The disease control rate with RT + TMZ was 63%. Median OS of the entire study population was 10.2 months (95% CI 6.6–13.8), and median PFS was 4.2 months (95% CI 3.2–5.2). The ECOG PS, the extent of resection, and the RT + TMZ were significant prognostic factors in the univariate analysis for OS, but only the RT + TMZ was a significant independent OS predictor in the multivariate analysis (HR = 3.1, 95% IC 1.3–7.7, p = 0.014). The incidence of mGBM is not rare. RT + TMZ is confirmed to be an independent prognostic factor for survival and a safe and effective treatment. When feasible, RT + TMZ should be considered as a possible first-line treatment. The role of the extent of resection is still unclear.  相似文献   
80.
Purpose The purpose of the study was to evaluate the effect on visual function of orally administered CDP-choline in addition to patching for the treatment of amblyopia in children. Methods This was an open label parallel group study comparing patching plus oral CDP-choline with patching alone. Sixty-one participants (aged between 5 and 10 years) suffering from anisometropic or strabismic amblyopia were divided at random into two groups: Group A, 800 or 1,200 mg (according to the body weight) of orally administered CDP-choline and 2-h patching a day; Group B, 2-h patching a day. Both groups were treated for 30 consecutive days. A follow-up visit was set 60 days after the treatment was discontinued. The main outcome measure was the change in visual acuity of amblyopic eyes as measured by Snellen’s E charts. The secondary outcome measures were changes in the visual acuity of amblyopic eye as measured by isolated letters (Snellen’s E) and changes in the contrast sensitivity of amblyopic eyes. Results The addition of CDP-choline to patching therapy was not found to be more effective than patching alone after 30-day treatment. The present results showed that adding CDP-choline to patching stabilised the effects obtained during the treatment period. In fact, whereas the participants treated only with patching showed a decrease in visual acuity at 90 days, these receiving CDP-choline and patching combined appeared to maintain the results obtained (two-way ANOVA: P = 0.0042). Similar results were obtained when measuring visual acuity by isolated Snellen’s E letters. Conclusions In amblyopic patients, CDP-choline combined with patching contributes to obtaining more stable effects than patching alone. Fabio De Gregorio works as an advisor for Tubilux Pharma S.p.A. The authors have full control of all primary data and they agree to allow Graefe’s Archives for Clinical and Experimental Ophthalmology to review their data if requested.  相似文献   
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