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31.
Thiago Santos Ferreira Manuella Lanzetti Marina Valente Barroso Carlos Romualdo Rueff-Barroso Cláudia Farias Benjamim Lycia de Brito-Gitirana Luís Cristóvão Porto Samuel Santos Valença 《Inflammation》2014,37(5):1355-1365
Our aim was to investigate the effects of four different statins on acute lung inflammation induced by cigarette smoke (CS). C57BL/6 male mice were divided into a control group (sham-smoked) and mice exposed to CS from 12 cigarettes/day for 5 days. Mice exposed to CS were grouped and treated with vehicle (i.p.), atorvastatin (10 mg/kg), pravastatin (10 mg/kg), rosuvastatin (5 mg/kg), or simvastatin (20 mg/kg). Treatment with statins differentially improved the pulmonary response when compared to the CS group. Atorvastatin and pravastatin demonstrated slightly effects on inflammation and oxidative stress. Rosuvastatin demonstrated the best anti-inflammatory effect, whereas simvastatin demonstrated the best antioxidant response. 相似文献
32.
Jakob Skou Pedersen Eivind Valen Amhed M. Vargas Velazquez Brian J. Parker Morten Rasmussen Stinus Lindgreen Berit Lilje Desmond J. Tobin Theresa K. Kelly S?ren Vang Robin Andersson Peter A. Jones Cindi A. Hoover Alexei Tikhonov Egor Prokhortchouk Edward M. Rubin Albin Sandelin M. Thomas P. Gilbert Anders Krogh Eske Willerslev Ludovic Orlando 《Genome research》2014,24(3):454-466
Epigenetic information is available from contemporary organisms, but is difficult to track back in evolutionary time. Here, we show that genome-wide epigenetic information can be gathered directly from next-generation sequence reads of DNA isolated from ancient remains. Using the genome sequence data generated from hair shafts of a 4000-yr-old Paleo-Eskimo belonging to the Saqqaq culture, we generate the first ancient nucleosome map coupled with a genome-wide survey of cytosine methylation levels. The validity of both nucleosome map and methylation levels were confirmed by the recovery of the expected signals at promoter regions, exon/intron boundaries, and CTCF sites. The top-scoring nucleosome calls revealed distinct DNA positioning biases, attesting to nucleotide-level accuracy. The ancient methylation levels exhibited high conservation over time, clustering closely with modern hair tissues. Using ancient methylation information, we estimated the age at death of the Saqqaq individual and illustrate how epigenetic information can be used to infer ancient gene expression. Similar epigenetic signatures were found in other fossil material, such as 110,000- to 130,000-yr-old bones, supporting the contention that ancient epigenomic information can be reconstructed from a deep past. Our findings lay the foundation for extracting epigenomic information from ancient samples, allowing shifts in epialleles to be tracked through evolutionary time, as well as providing an original window into modern epigenomics.Ancient DNA research started in the mid-1980s with the successful cloning and sequencing of a short mitochondrial DNA fragment from the quagga zebra, a species that became extinct in the early 20th century (Higuchi et al. 1984). Soon after, the invention of PCR unlocked access to this fragmented and degraded DNA material (Pääbo 1989), making it possible to amplify short gene markers of interest and compare their sequence to that from extant organisms. This illuminated a range of topics ranging from the reconstruction of the evolutionary origins of several now-extinct iconic mammals (Orlando et al. 2003; Krause et al. 2006), the evaluation of the possible role played by major past climatic changes in driving mega-fauna extinctions (Shapiro et al. 2004; Campos et al. 2010; Lorenzen et al. 2011), to the identification of the pathogens responsible for massive historical outbreaks (Taubenberger et al. 1997).However, before the advent of next-generation sequencing (NGS) platforms, the amount of ancient sequence information one had access to was limited to several tens of thousands of nucleotides at best (Noonan et al. 2005, 2006), and until very recently, sequencing whole ancient mitochondrial genomes was considered a major achievement (Cooper et al. 2001; Krause et al. 2006). Parallel sequencing of millions to billions of short DNA fragments has revolutionized ancient DNA research, and today a series of ancient genomes has been reconstructed from humans (Rasmussen et al. 2010, 2011; Keller et al. 2012; Raghavan et al. 2013), archaic hominins (Green et al. 2010; Reich et al. 2010; Meyer et al. 2012), the woolly mammoth (Miller et al. 2008), and several microbial pathogens (Bos et al. 2011; Martin et al. 2013; Schuenemann et al. 2013; Yoshida et al. 2013). Those mainly date back to recent historical periods or the Late Pleistocene, but most recently, the characterization of a 560,000- to 780,000-yr-old horse draft genome revealed that genomic information could be retrieved over much longer evolutionary time scales, probably up until the last million years (Orlando et al. 2013).Ancient genomes have provided important new insights into human evolution and dispersals (Rasmussen et al. 2010, 2011; Keller et al. 2012; Raghavan et al. 2013), revealing an admixture between contemporary human ancestors and archaic hominins (Green et al. 2010; Reich et al. 2010; Meyer et al. 2012) and multiple early human expansions into both Asia and North America (Rasmussen et al. 2010, 2011). The information gained from these samples has largely been limited to nucleotide polymorphisms. Unlike mutations, epigenetic modifications do not alter the underlying DNA sequence, but can be inherited across cell divisions and from parents to offspring and can control gene expression by reshaping cytosine methylation landscapes, nucleosome organization, and histone modification patterns. The range of biological processes that depend on some level of epigenetic regulation is diverse and includes imprinting (Bird 2002), transposition (Hollister and Gaut 2009), cell differentiation (Meissner et al. 2008), and cancer (Teschendorff et al. 2011). In this study, we use the Saqqaq genome that was retrieved from an ∼4000-yr-old tuft of hair of a Paleo-Eskimo from Greenland and sequenced to an average depth of 20× (Rasmussen et al. 2010). We demonstrate that NGS data can be used in the absence of bisulfite or further experimental treatment to directly infer genome-wide nucleosome organization and regional methylation levels, thereby providing the first survey of an ancient epigenome. 相似文献
33.
34.
José Vitor Lima-Filho Liliane Vilela Martins Danielle Cristina de Oliveira Nascimento Roberta Ferreira Ventura Jacqueline Ellen Camelo Batista Ayrles Fernanda Brandão Silva Maria Taciana Ralph Renata Valença Vaz Carlos Boa-Viagem Rabello Isabella de Matos Mendes da Silva Joaquim Evêncio-Neto 《The Brazilian journal of infectious diseases》2013,17(1):54-61
The zoonotic potential to cause human and/or animal infections among multidrug-resistant extraintestinal pathogenic Escherichia coli from avian origin was investigated. Twenty-seven extraintestinal pathogenic E. coli isolates containing the increased survival gene (iss) were obtained from the livers of healthy and diseased poultry carcasses at two slaughterhouses in Salvador, northeastern Brazil. The antimicrobial resistance-susceptibility profiles were conducted with antibiotics of avian and/or human use by the standardized disc-diffusion method. Antimicrobial resistance was higher for levofloxacin (51.8%), amoxicillin/clavulanic acid (70.4%), ampicillin (81.5%), cefalotin (88.8%), tetracycline (100%) and streptomycin (100%). The minimum inhibitory concentrations above the resistance breakpoints of doxycycline, neomycin, oxytetracycline and enrofloxacin reached, respectively, 88.0%, 100%, 75% and 91.7% of the isolates. Strains with high and low antimicrobial resistance were i.p. administered to Swiss mice, and histopathological examination was carried out seven days after infection. Resistance to goat and human serum complement was also evaluated. The results show that Swiss mice challenged with strain 2B (resistant to 11 antimicrobials) provoked a severe degeneration of hepatocytes besides lymphocytic infiltration in the liver, whereas the spleen showed areas of degeneration of the white and red pulp. Conversely, the spleen and liver of mice challenged with strain 4A (resistant to two antimicrobials) were morphologically preserved. In addition, complement resistance to goat and human serum was high for strain 2B and low for strain 4A. Our data show that multidrug resistance and pathogenesis can be correlated in extraintestinal pathogenic E. coli strains obtained from apparently healthy poultry carcasses, increasing the risk for human public healthy. 相似文献
35.
Qinghua Wu Ragnhild A Lothe Terje Ahlquist Ilvars Silins Claes G Tropé Francesca Micci Jahn M Nesland Zhenhe Suo Guro E Lind 《Molecular cancer》2007,6(1):45
Background
The epigenetics of ovarian carcinogenesis remains poorly described. We have in the present study investigated the promoter methylation status of 13 genes in primary ovarian carcinomas (n = 52) and their in vitro models (n = 4; ES-2, OV-90, OVCAR-3, and SKOV-3) by methylation-specific polymerase chain reaction (MSP). Direct bisulphite sequencing analysis was used to confirm the methylation status of individual genes. The MSP results were compared with clinico- pathological features. 相似文献36.
Valença MM 《Arquivos de neuro-psiquiatria》2002,60(1):181; author reply 182
37.
Franzius C Kopka K van Valen F Riemann B Sciuk J Schober O 《Nuclear medicine and biology》2002,29(4):483-490
The cellular transport systems and the transport kinetics of [123I]IMT uptake into non-malignant extracranial cells were characterized for the first time. Human fibroblasts were chosen as non-malignant extracranial cells as they are found ubiquitous in the body. [123I]IMT is exclusively transported into fibroblasts via the sodium independent system L. An apparent Michaelis constant K(m) = 116.2 +/- 18.9 microM and a maximum transport velocity V(max) = 191.6 +/- 13.9 pmol x (10(6) cells)(-1) x min(-1) were calculated for the sodium-independent transport. These results were compared with those determined in two malignantly transformed extracranial cell lines, the human Ewing's sarcoma cell lines VH-64 and CADO-ES-1. 相似文献
38.
The objective of this study was to analyze some clinical and epidemiologic aspects, as well as the follow up of 180 patients with Bell's palsy. In the study population there was a predominance of female (66.7%). Two peaks of incidence in the age distribution were identified: third-fourth and sixth decades of life. In the group of 180 patients there were 198 events of facial paralysis, 17 recurrences and in one patient the paralysis was bilateral at the onset. In 15 patients (8.3%) there were recurrences of the facial paralysis, in 12 cases (70.6%) the recurrences were ipsilateral. The left side of the face was involved in 55.6% of the cases. In eight patients the paralysis occurred during pregnancy (n=5) or puerperium (n=3). As associated conditions we found: arterial hypertension (11.7%), diabetes mellitus (11.1%), pregnancy or puerperium (4.4%; 6.7% in the women), and neurocysticercosis (1.1%). In 72.8% of the cases no association with such conditions was found. In 22.8% of the patients some kind of sequelae were identified: hemifacial spasm (12.8%), partial recovery of the motor deficit (10.6%), syndrome of the crocodile tears (3.3%), sincinetic contraction (2.8%), and the Marcus Gunn inverse phenomenon (1.1%). In conclusion, this study shows that the idiopathic facial paralysis may lead to important sequelae in more than 20% of the patients. 相似文献
39.
Sonya Hamilton Guro Huby Alison Tierney Alison Powell Tara Kielmann Aziz Sheikh Hilary Pinnock 《BMC health services research》2008,8(1):248
Background
Healthcare systems globally are reconfiguring to address the needs of people with long-term conditions such as respiratory disease. Primary Care Organisations (PCOs) in England and Wales are charged with the task of developing cost-effective patient-centred local models of care. We aimed to investigate how PCOs in England and Wales are reconfiguring their workforce to develop respiratory services, and the background factors influencing service redesign. 相似文献40.
Medeiros AC Aires-Neto T Marchini JS Brandão-Neto J Valença DM Egito ES 《Digestive surgery》2004,21(5-6):401-405
BACKGROUND/AIMS: Enterocutaneous fistulas are associated with prolonged hospital stay, high morbidity/mortality, and increased hospital costs. This study aims to describe the use of a vacuum system and normal oral diet in dealing with this problem. METHODS: Seventy-four consecutive patients with recent and defined external postoperative fistulas were analyzed. Abdominal imaging was used to exclude abscess and distal obstruction. The fistula tract was sealed with Foley catheter, connected to a negative pressure flask, changed daily for 5, 10 or 15 days, as necessary. A normal oral diet was permitted. RESULTS: No patient died. Serum albumin and transferrin showed significantly higher levels at the end of treatment than at the beginning. The moderate and low-output fistulas had the best results (97% closed). Forty-eight (65%) fistulas closed after 5 days, 16 (22%) after 10 days and 4 (5%) after 15 days. Treatment failed in 6 (8%) patients, who subsequently underwent surgery. The fistula did not close in 1 patient with a low output. The cost of the treatment was USD 41.75/day and it was considered cost-effective. CONCLUSIONS: The vacuum system demonstrated good results in the treatment of fistulas. It included simplicity, low cost, short hospital stay, absence of skin breakdown, normal eating, good nutrition and activity patterns. 相似文献