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11.
A functional survey of the enhancer activity of conserved non-coding sequences from vertebrate Iroquois cluster gene deserts 总被引:7,自引:4,他引:7
de la Calle-Mustienes E Feijóo CG Manzanares M Tena JJ Rodríguez-Seguel E Letizia A Allende ML Gómez-Skarmeta JL 《Genome research》2005,15(8):1061-1072
Recent studies of the genome architecture of vertebrates have uncovered two unforeseen aspects of its organization. First, large regions of the genome, called gene deserts, are devoid of protein-coding sequences and have no obvious biological role. Second, comparative genomics has highlighted the existence of an array of highly conserved non-coding regions (HCNRs) in all vertebrates. Most surprisingly, these structural features are strongly associated with genes that have essential functions during development. Among these, the vertebrate Iroquois (Irx) genes stand out on both fronts. Mammalian Irx genes are organized in two clusters (IrxA and IrxB) that span >1 Mb each with no other genes interspersed. Additionally, a large number of HCNRs exist within Irx clusters. We have systematically examined the enhancer activity of HCNRs from the IrxB cluster using transgenic Xenopus and zebrafish embryos. Most of these HCNRs are active in subdomains of endogenous Irx expression, and some are candidates to contain shared enhancers of neighboring genes, which could explain the evolutionary conservation of Irx clusters. Furthermore, HCNRs present in tetrapod IrxB but not in fish may be responsible for novel Irx expression domains that appeared after their divergence. Finally, we have performed a more detailed analysis on two IrxB ultraconserved non-coding regions (UCRs) duplicated in IrxA clusters in similar relative positions. These four regions share a core region highly conserved among all of them and drive expression in similar domains. However, inter-species conserved sequences surrounding the core, specific for each of these UCRs, are able to modulate their expression. 相似文献
12.
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
13.
Martina Meoli Franco Muggli Sebastiano A.G. Lava Mario G. Bianchetti Carlo Agostoni Claudine Kocher Thomas W. Bührer Letizia Ciliberti Giacomo D. Simonetti Gregorio P. Milani 《Nutrients》2021,13(5)
Vitamin D has been claimed to be effective in the response to infections, including the respiratory syndrome coronavirus 2 (SARS-CoV-2). It is supposed that lockdown measures and fear of SARS-CoV-2 infection might reduce vitamin D levels through the modification of lifestyle. However, very few data exist on the association between lockdown measures and vitamin D status in humans. For this cross-sectional comparative study, adolescents (n = 298) aged 18 to 19 years were enrolled during the compulsory military fitness-for-duty evaluation between July and December 2020 in Southern Switzerland. Beyond anthropometric measurements, participants filled in a structured questionnaire about their lifestyle and a blood specimen was sampled for the determination of total 25-hydroxy-vitamin D. The obtained data were compared with those of 437 adolescents enrolled at the military fitness-for-duty evaluation during the same period of the year in the context of the CENERI study (2014–2016). The anthropometric measures were similar between the two study groups. The levels of vitamin D were also comparable (77 (64–91) vs. 74 (60–92) nmol/L, p = 0.50; median and interquartile range). A total of 38 (13%) and 43 (9.8%) subjects presented insufficient (<50 nmol/L) levels of vitamin D (p = 0.42) during the current pandemic and in the CENERI study, respectively. These data do not support the hypothesis that during the SARS-CoV-2 pandemic, late adolescents are at higher risk of vitamin insufficiency. 相似文献
14.
Chiara Mazziotta Carmen Lanzillotti Marcello Govoni Simonetta Falzoni Maria Letizia Tramarin Elisa Mazzoni Mauro Tognon Fernanda Martini John Charles Rotondo 《Immunology》2023,168(4):671-683
Oncogenic Merkel cell polyomavirus (MCPyV) provokes a widespread and asymptomatic infection in humans. Herein, sera from healthy children and young adults (HC, n = 344) aged 0–20 years old were evaluated for anti-MCPyV immunoglobulin G (IgG) and IgM antibodies employing a recently developed immunoassay. Serum MCPyV IgG data from healthy subjects (HS, n = 510) and elderlies (ES, n = 226), aged 21–65/66–100 years old, from our previous studies, were included. The anti-MCPyV IgG and IgM rates in HC sera were 40.7% and 29.7%, respectively. A lower prevalence of anti-MCPyV IgGs was found in HC aged 0–5 years old (13%) compared to 6–10 (52.3%), 11–15 (60.5%) and 16–20 years old (61.6%) cohorts. Age-stratified HCs exhibited similar anti-MCPyV IgM rates (27.9%–32.9%). Serological profiles indicated that anti-MCPyV IgGs and IgMs had low optical densities (ODs) during the first years of life, while IgM ODs appeared to decrease throughout young adulthood. A lower anti-MCPyV IgGs rate was found in HC (40.7%) than HS (61.8%) and ES (63.7%). Upon the 5-years range age-stratification, a lower anti-MCPyV IgGs rate was found in the younger HC cohort aged 0–5 years old compared to the remaining older HC/HS/ES cohorts (52.3%–72%). The younger HC cohort exhibited the lowest anti-MCPyV IgG ODs than the older cohorts. Low anti-MCPyV IgMs rates and ODs were found in the 21–25 (17.5%) and 26–30 (7.7%) years old cohorts. Our data indicate that, upon an early-in-life seroconversion, the seropositivity for oncogenic MCPyV peaks in late childhood/young adulthood and remains at high prevalence and relatively stable throughout life. 相似文献
15.
Letizia Mazzini Daniela Testa Carla Balzarini Gabriele Mora 《Journal of neurology》1994,241(4):223-227
Based on the hypothesis that free radicals play a general role in the neurodegenerative process in motor neuron disease, we tested selegiline in a group of patients affected by amyotrophic lateral sclerosis (ALS) to examine whether it might modify the progression of the disease. Patients were admitted if they were 25–80 years old and had a confirmed diagnosis of ALS with symptoms lasting no longer than 24 months. Patients with familial ALS, pure progressive bulbar palsy, primary lateral sclerosis or progressive muscle atrophy were excluded; a total of 111 patients were recruited. Fifty-three patients were randomly assigned to receive the drug (selegiline 10 mg/day orally for 6 months) and the remaining 58 were considered ALS controls. Mortality was similar in the two groups (4 and 5 patients respectively), though the difference was not statistically significant. Among the survivors, mean MRC and Norris disability scores and forced vital capacity were fairly similar in the two groups at all times and no statistically significant difference between treated and untreated patients was found. The results did not change when the data were related to age, duration and characteristics of onset of the disease. The rate of progression was significantly more rapid in patients with bulbar symptoms in both groups. Our data do not show any significant effect of selegiline in modifying the progression of ALS. 相似文献
16.
Montorsi F Salonia A Maga T Bua L Guazzoni G Barbieri L Barbagli G Chiesa R Pizzini G Rigatti P 《The Journal of urology》2000,163(6):1704-1708
PURPOSE: We assessed the long-term outcome of plaque incision and vein grafting in select patients with Peyronie's disease by extensive preoperative and postoperative subjective and objective analysis. MATERIALS AND METHODS: From January 1995 to June 1998, 50 men 28 to 62 years old (mean age 44) underwent surgery. Patients were evaluated preoperatively, 3 months after surgery and at a mean long-term followup of 32 months by sexual history, physical examination, determination of penile length and degree of curvature, dynamic color power Doppler sonography of the penile vessels and nocturnal RigiScan* evaluation for 3 nights. Study inclusion criteria were penile curvature 45 degrees or greater that made vaginal intromission impossible, stable disease for at least 6 months, patient reported normal penile rigidity, normal penile hemodynamics on color power Doppler ultrasound, normal nocturnal penile rigidity with at least 1 erection nightly (including base and tip rigidity greater than 60%, and a duration of 10 minutes) and absent base-tip discrepancies. Plaque was usually approached via a combined subcoronal and midline sagittal scrotal incision. Maximal rigidity was created intraoperatively and 1 to 3 plaque incisions were made. Saphenous vein patches were then grafted at the incision sites. Postoperatively patients were systemically treated with neurotrophic factors and low molecular weight heparin. Local vacuum supported corporeal stretching was done and weekly alprostadil injections were given to optimize corporeal oxygenation. RESULTS: At long-term followup complete penile straightening was achieved in 40 cases (80%), minor residual curvature of 30 degrees or less persisted in 7 (14%) and significant disease recurred in 3 (6%). Penile rigidity was equal to that preoperatively in 47 patients (94%), while 3 (6%) reported clinically significant decreased potency. Penile length was equal to that preoperatively in 30 patients (60%), while 20 (40%) noticed slight penile shortening. Postoperatively penile color power Doppler sonography showed vascular impairment in 5 men (10%) and nocturnal RigiScan testing revealed a significant decrease in nightly erections in 5 (10%). Surgical complications included penile hypoesthesia in 1 case (2%), penile hematoma in 2 (4%), wound infection in 1 (2%) and glandular ischemia in 1 (2%). CONCLUSIONS: Plaque incision and vein grafting achieved satisfactory clinical results in the majority of patients with severe and stable Peyronie's disease, intact penile rigidity preoperatively, normal penile color power Doppler ultrasound and normal nocturnal RigiScan testing. 相似文献
17.
Isabel Santillán Palencia Letizia Benassi StradaLaura Blasco Gastón Inma Rincón RicoteRomán Curiel Rodado Antonio González González 《Progresos de Obstetricia y Ginecología》2008
Objectives
To evaluate maternal and fetal outcomes of multiple pregnancy according to route of delivery.Material and methods
We performed a retrospective study of all twin deliveries in the previous 5 years and evaluated the route of delivery, especially in the final year. The information was recorded with Microsoft EXCEL and was analyzed with the statistical program SPSS 12.0 for Windows.Results
The mean gestational age was 35.3 weeks. Route of delivery was through cesarean section in 59.8%. The mean interval between twins was 7.82 minutes when the first twin was delivered vaginally. Neonatal morbidity was found in 49%, and was higher in the second twin and in preterm deliveries.Conclusions
Multiple pregnancies are associated with a large number of maternal and perinatal complications, as well as with a greater number of cesarean sections. Consequently, correct intrapartum management is required to reduce neonatal morbility as far as possible. 相似文献18.
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20.
Paolo Ortolani Antonio Marzocchi Cinzia Marrozzini Tullio Palmerini Francesco Saia Carlo Serantoni Matteo Aquilina Simona Silenzi Federica Baldazzi Daniele Grosseto Nevio Taglieri Robin M T Cooke Maria Letizia Bacchi-Reggiani Angelo Branzi 《European heart journal》2006,27(13):1550-1557
AIMS: Treatment delay is a powerful predictor of survival in ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI). We investigated effectiveness of pre-hospital diagnosis of STEMI with direct referral to PCI, alongside more conventional referral strategies. METHODS AND RESULTS: From January 2003 to December 2004, 658 STEMI patients were referred for primary PCI at our intervention laboratory. Three predefined referral routes were compared: (1) for patients within 90 min drive of the PCI centre, pre-hospital diagnosis and direct transportation (n=166), (2) diagnosis at the interventional hospital emergency department (n=316), (3) diagnosis at local hospitals before transportation (n = 176). Pre-hospital diagnosis was associated with more than 45 min reduction in treatment delay (P = 0.001). No significant difference in in-hospital mortality was apparent in the overall study population. In the cardiogenic shock subgroup (n = 80), pre-hospital diagnosis was associated with a two-thirds reduction in in-hospital mortality (P = 0.019); mortality was only 6.2% in shock patients who underwent PCI in < 2 h. CONCLUSION: This study shows that pre-hospital diagnosis can provide a reduction in primary PCI treatment delay, and suggests the hypothesis that this referral strategy might provide survival benefits to patients with cardiogenic shock. 相似文献