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991.
Ramalhosa MJ Paíga P Morais S Ramos S Delerue-Matos C Oliveira MB 《Food and chemical toxicology》2012,50(2):162-167
The concentrations of 18 polycyclic aromatic hydrocarbons (PAHs) were determined in three commercially valuable fish species (sardine, Sardina pilchardus; chub mackerel, Scomber japonicus; and horse mackerel, Trachurus trachurus) from the Atlantic Ocean. Specimens were collected seasonally during 2007–2009. Only low molecular weight PAHs were detected, namely, naphthalene, acenaphthene, fluorene and phenanthrene. Chub mackerel (1.80–19.90 μg/kg ww) revealed to be significantly more contaminated than horse mackerel (2.73–10.0 μg/kg ww) and sardine (2.29–14.18 μg/kg ww). Inter-specific and inter-season comparisons of PAHs bioaccumulation were statistically assessed. The more relevant statistical correlations were observed between PAH amounts and total fat content (significant positive relationships, p ? 0.05), and season (sardine displayed higher amounts in autumn–winter while the mackerel species showed globally the inverse behavior). The health risks by consumption of these species were assessed and shown to present no threat to public health concerning PAH intakes. 相似文献
992.
Nisha Verma Mario Pink Frank Petrat Albert W. Rettenmeier Simone Schmitz-Spanke 《Archives of toxicology》2012,86(12):1861-1871
More than 90?% of all bladder cancers are transitional cell carcinomas arising from the cells lining the inside of the hollow organ (uroepithelium). Cell cultures from primary urinary bladder epithelial cells (PUBEC) of pigs were established to assess the uptake, intracellular concentration, and subcellular distribution of the environmental pollutant benzo(a)pyrene (BaP). During treatment of the cells with 0.5?μM BaP for up to 24?h, intracellular concentration of BaP increased without saturation but with marked differences between various PUBEC pools. Analysis of BaP uptake by laser scanning microscopy indicated that BaP is rapidly partitioned into the cell membrane, while only a slight but significant increase in BaP fluorescence intensity was observed in the cytosol and nucleus. Spectrofluorometric quantification of BaP in PUBEC using ex situ calibration revealed a strong accumulation of BaP, leading to intracellular concentrations ranging from 7.28 to 35.70?μM in cells exposed to 0.5?μM BaP and from 29.9 to 406.64?μM in cells exposed to 10?μM BaP. These results were confirmed by gas chromatographic mass spectrometric analysis. Apoptotic cell nuclei were assessed by TUNEL analysis to see whether BaP exposure at the given concentrations results in a toxic effect. While apoptotic cells were barely detectable in control epithelial cells, there was a marked elevation in apoptosis in the BaP-exposed cells. In conclusion, a comprehensive study on uptake and quantification of BaP in epithelial cells from pig bladder is reported for the first time. The study may be helpful in understanding the pattern of BaP uptake and distribution in bladder and its possible implication in bladder cancer development. 相似文献
993.
994.
S de Biase G Merlino S Lorenzut M Valente GL Gigli 《Expert opinion on drug metabolism & toxicology》2012,8(10):1247-1261
Introduction: Restless legs syndrome (RLS) is a common neurological disorder that might impair nocturnal rest causing decreased alertness, depressed mood, reduced job performance, and poor quality of life. In patients affected by severe RLS, a pharmacological treatment is mandatory. Areas covered: The present review is based on a search using PubMed from 1994 to 2012. It is focused on the Absorption, Distribution, Metabolism, Elimination and Toxicology (ADMET) characteristics of the most used medications for RLS. In particular, the ADMET characteristics of dopaminergic agents, anticonvulsants able to improve neuropathic pain, and iron were discussed. Expert opinion: Clinical trials have showed that non-ergolic dopamine agonists are efficacious and safe for patients affected by moderate to severe idiopathic RLS. However, no head-to-head study has compared the long-term effects of the three dopamine agonists approved by the FDA for RLS (ropinirole, pramipexole, and rotigotine). Moreover, further studies should investigate the extended-release formulation of ropinirole and pramipexole in RLS patients affected by all day long distressing symptoms. A standardized treatment for symptomatic forms of RLS is lacking. Randomized, placebo-controlled trials should be performed at least in RLS patients with peripheral neuropathic and chronic kidney disease. Concerning RLS due to iron deficiency, a head-to-head study comparing efficacy, safety and compliance of oral iron versus intravenous one seems to be needed. 相似文献
995.
Campos SB Miranda DM Souza BR Pereira PA Neves FS Tramontina J Kapczinski F Romano-Silva MA Correa H 《Psychiatric genetics》2011,21(2):106-111
Frequent comorbidity between panic disorder (PD) and mood disorders has been widely reported in clinical and epidemiological studies and, recently, an increasing attention has been paid to the cooccurrence of PD and bipolar disorder (BD). Several studies have shown that an imbalance of serotonin activity could be related to panic symptoms. Tryptophan hydroxylase 2 (TPH2) are plausible candidates for the association with PD. The aim of this study is to investigate a possible association between TPH2 gene polymorphisms and the PD comorbidity susceptibility.Our sample consisted of 515 patients; 274 patients with BD (subtypes I and II), including 45 patients with lifetime panic disorder comorbidity and 241 controls. These patients were genotyped for eight tagging single nucleotide polymorphisms of the gene of human TPH2. We found significant differences between patients with BD, with panic disorder comorbidity, and controls in the allelic analysis (rs4448731, P=0.0069; rs4565946, P=0.0359; rs4760820, P=0.0079; rs1487275, P=0.0439) and genotypic analysis (rs4448731, P=0.011; rs4760820, P=0.0259). We also identified significant differences between patients with BD, with and without panic disorder comorbidity in the allelic analysis (rs4448731, P=0.004; rs4565946, P=0.011; rs11179000, P=0.031; rs4760820, P=0.018; rs1487275, P=0.038; rs10879357, P=0.023) and genotypic analysis (rs4448731, P=0.004; rs4565946, P=0.010; rs4760820, P=0.023; rs10879357, P=0.052). The haplotype analysis in the group of patients with BD, with and without panic disorder comorbidity, was also significant (rs4448731-rs4565946, P=0.0190; rs4448731-rs4565946, P=0.0220; rs10506645-rs4760820, P=0.0360). Further studies are needed to replicate the positive association that we observed. 相似文献
996.
Langlois F Langlois MF Carpentier AC Brown C Lemieux S Hivert MF 《Physiology & behavior》2011,104(3):373-377
Weight gain and appetite regulation are complex interplays between internal and external cues. Our aim was to investigate the association of eating behaviors with ghrelin taking into account lifestyle. We conducted a cross-sectional analysis in a sample of first-year university students at the Université de Sherbrooke. We collected medical history, anthropometric measurements, vital signs, fitness index, and fasting blood samples. Questionnaires included a lifestyle questionnaire and the Three-Factor Eating Questionnaire (TFEQ) estimating dietary restraint, disinhibition and hunger. We recruited 308 participants aged 20.7 ± 3.2 years and a mean BMI of 23.3 ± 3.4 kg/m2. Hunger score was significantly associated with ghrelin levels (r = 0.11, P < 0.05). In women, this association was independent of age, BMI, dietary and lifestyle factors (P = 0.02). The association between ghrelin level and hunger score was observable in leaner individuals (r = 0.28, p < 0.0001) but not in heavier individuals (r = − 0.08, p = 0.34; stratified by BMI < vs > 22.6 kg/m2). Restraint (R) and disinhibition (D) were not associated with ghrelin levels. The three eating behaviors demonstrated expected correlations with lifestyle supporting the validity of the TFEQ in this cohort. In conclusion, we demonstrated that ghrelin, a biological marker, is associated with self-reported perception of hunger, independently of anthropometric measures and lifestyle. 相似文献
997.
Rubio I Seitz H Canali E Sehr P Bolchi A Tommasino M Ottonello S Müller M 《Virology》2011,409(2):348-359
The N-terminal region of the human papillomavirus (HPV) L2 protein has been shown to contain immune epitopes able to induce the production of neutralizing and cross-neutralizing antibodies (Gambhira et al., 2007; Kawana et al., 1999). Using bacterial thioredoxin as a scaffold, we managed to enhance the immunogenicity of putative L2 neutralizing epitopes, but only a minor fraction of the resulting immune responses was found to be neutralizing (Rubio et al., 2009). To determine the recognition patterns for non-neutralizing, neutralizing and cross-neutralizing antibodies, we isolated and characterized a panel of 46 monoclonal antibodies directed against different HPV16 L2 epitopes. Four of such antibodies proved to be neutralizing, and two of them, both targeting the amino acid (aa) 20-38 region of L2, were found to cross-neutralize a broad range of papillomaviruses. The epitopes recognized by neutralizing and cross-neutralizing antibodies were mapped at high resolution and were found to be characterized by distinct recognition patterns. Even in the case of the L2 20-38 epitope, cross-neutralization of HPV31 pseudovirions proved to be extremely inefficient, and this was found to be primarily due to the lack of a proline residue at position 30. HPV16 specific amino acids in this region also appear to be responsible for the lack of cross-neutralizing activity, thus suggesting a potential immune escape mechanism. For the aa 71-80 region, instead, the data indicate that restriction of neutralization to HPV16 is due to sequence (or structural) differences laying outside of the epitope. Besides providing new insights on the molecular bases of L2-mediated immune reactivity, the present data may pave the way to novel vaccination approaches specifically evoking cross-neutralizing antibody responses. 相似文献
998.
Hach S Ishihara M Keller PE Schütz-Bosbach S 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,212(4):563-574
Analogously to the visual system, somatosensory processing may be segregated into two streams, with the body constituting
either part of the action system or a perceptual object. Experimental studies with participants free from neurological disease
which test this hypothesis are rare, however. The present study explored the contributions of the two putative streams to
a task that requires participants to estimate the spatial properties of their own body. Two manipulations from the visuospatial
literature were included. First, participants were required to point either backward towards pre-defined landmarks on their
own body (egocentric reference frame) or to a forward projection of their own body (allocentric representation). Second, a
manipulation of movement mode was included, requiring participants to perform pointing movements either immediately, or after
a fixed delay, following instruction. Results show that accessing an allocentric representation of one’s own body results
in performance changes. Specifically, the spatial bias shown to exist for body space when pointing backward at one’s own body
disappears when participants are requested to mentally project their body to a pre-defined location in front space. Conversely,
delayed execution of pointing movements does not result in performance changes. Altogether, these findings provide support
for a constrained dual stream hypothesis of somatosensory processing and are the first to show similarities in the processing
of body space and peripersonal space. 相似文献
999.
Rainer A Spadaccio C Sedati P De Marco F Carotti S Lusini M Vadalà G Di Martino A Morini S Chello M Covino E Denaro V Trombetta M 《Annals of biomedical engineering》2011,39(7):1882-1890
Sternal synthesis after median sternotomy, a conventional access practice in thoracic and cardiac surgery, is at the basis of severe complications, often impairing the clinical outcome of surgical interventions. In this work, we propose the use of an acellular biomaterial scaffold, to be interposed across the fracture rime during closure operations, directly exposing the biomaterial to bone marrow, in order to expedite healing process. A rabbit model of median sternotomy was performed and an electrospun scaffold composed of a hydroxyapatite-loaded absorbable biopolymer (poly-L: -lactide), shaped into a fibrillar structure, was used. CT follow-up confirmed a complete healing in the scaffold-treated group 1 week before the control. Histological evaluation demonstrated presence of newly formed bone trabeculae among scaffold fibers showing a higher degree of maturity with respect to the control untreated group. The proposed approach is able to both guide a more rapid healing and modulate inflammatory response across the wound site, resulting in improved healing and tissue remodeling with respect to conventional closure technique. 相似文献