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71.
Antonio Bevilacqua Monica Mischitelli Valeria Pietropaolo Emanuela Ciuffreda Milena Sinigaglia Maria Rosaria Corbo 《PloS one》2015,10(10)
Alicyclobacillus acidoterrestris is the main cause of most spoilage problems in fruit juices and acidic products. Since soil borne species often contaminate fruit juices and do not need strict extreme requirements for survival, it is a great concern to investigate whether and how soil species could evolve from their ecological niches in microbial community to new environments as fruit juices. In this study, 23 isolates of thermo-acidophilic, spore-forming bacteria from soil were characterized by cultural and molecular methods. In addition, 2 strains isolated from a spoilage incident in pear juice were typed. Strains phenotyping showed that they could be grouped into 3 different clusters, and some isolates showed identical or quite similar patterns. Analyzing pH and temperature ranges for growth, the majority of strains were able to grow at values described for many species of Alicyclobacillus. Qualitative utilization of lysine, arginine and indole production from tryptophan revealed, for the first time, deamination of lysine and decarboxylation of arginine. Resistance to 5% NaCl as well as the ability to hydrolyze starch and gelatin, nitrate reduction, catalase and oxidase activities confirmed literature evidences. Examining of 16S rRNA, showed that isolates were divided into three blocks represented by effectively soil species and strains that are moving from soil to other possible growing source characterized by parameters that could strongly influence bacterial survival. RAPD PCR technique evidenced a great variability in banding patterns and, although it was not possible to obtain genotypically well-distinguished groups, it was feasible to appreciate genetic similarity between some strains. In conclusion, the investigation of a microbial community entails a combination of metagenomic and classic culture-dependent approaches to expand our knowledge about Alicyclobacillus and to look for new subspecies. 相似文献
72.
Emanuela Viggiano Marcellino Monda Alessandro Viggiano Andrea Viggiano Caterina Aurilio Bruno De Luca 《Molecular and cellular biochemistry》2010,339(1-2):149-154
Previous studies have demonstrated that there is an increase in oxidative stress in the cerebral cortex of rats after repeated painful stimulation and that long-lasting pain increases the production of superoxide ion (O2 ?), nitric oxide and peroxynitrite due to the activation of AMPA and NMDA receptors. The purpose of the present study was to evaluate the possible role of O2 ? in the transmission of oro-facial pain. Formaldehyde 1% was injected subcutaneously into one vibrissal pad of adult male Sprague-Dawley rats as a model of persistent pain, then O2 ? production and superoxide dismutase (SOD) activity were evaluated in the left and right spinal trigeminal nuclei. O2 ? production was revealed using dihidroetidium (DHE) injected at 10 or 45 min after the formalin injection in conscious or anaesthetized rats. A histochemical assay for SOD was performed to evaluate the activity of SOD at 10 min after the formalin injection. The results showed a significant increase in O2 ? production in the homolateral nucleus at 45 min. However, there was no significant difference between the two sides at 10 min after the formalin injection. No significant difference was observed in SOD activity between the two sides of the spinal trigeminal nucleus. This study demonstrated that there is an increased production of O2 ? in the second phase but not in the first phase of the formalin test; thus O2 ? is involved in pain induced by inflammation, but not in acute pain. 相似文献
73.
Still little information is available on the efficacy and toxicity of anti-Trop-2 antibodies in man. Findings on antibodies anti-Trop-1/Ep-CAM, a paralog molecule of Trop-2, may provide preliminary indications, and a low-affinity anti-Trop-1/Ep-CAM monoclonal antibody, failed to show any benefit in colon cancer patients. Other anti-Trop-1 antibodies, e.g. MT201, may bear more promise, as may more advanced molecular forms, e.g. a BiTE design (MT110) or trifunctional antibodies (catumaxomab). However, the efficacy of these reagents in cancer patients still needs to be proven in randomized clinical trials. 相似文献
74.
Collagen and mature elastic fibre organisation as a function of depth in the human cornea and limbus
Christina S. Kamma-Lorger Craig Boote Sally Hayes Julian Moger Manfred Burghammer Carlo Knupp Andrew J. Quantock Thomas Sorensen Emanuela Di Cola Nick White Robert D. Young Keith M. Meek 《Journal of structural biology》2010,169(3):424-430
A network of circumferentially oriented collagen fibrils exists in the periphery of the human cornea, and is thought to be pivotal in maintaining corneal biomechanical stability and curvature. However, it is unknown whether or not this key structural arrangement predominates throughout the entire corneal thickness or exists as a discrete feature at a particular tissue depth; or if it incorporates any elastic fibres and how, with respect to tissue depth, the circumcorneal annulus integrates with the orthogonally arranged collagen of the central cornea. To address these issues we performed a three-dimensional investigation of fibrous collagen and elastin architecture in the peripheral and central human cornea using synchrotron X-ray scattering and non-linear microscopy. This showed that the network of collagen fibrils circumscribing the human cornea is located in the posterior one-third of the tissue and is interlaced with significant numbers of mature elastic fibres which mirror the alignment of the collagen. The orthogonal arrangement of collagen in the central cornea is also mainly restricted to the posterior stromal layers. This information will aid the development of corneal biomechanical models aimed at explaining how normal corneal curvature is sustained and further predicting the outcome of surgical procedures. 相似文献
75.
It has been demonstrated that patients showing symptoms of chronic bacterial prostatitis but culture-negative prostate-specific specimens can benefit from administration of antibacterial agents. This suggests that organisms that are not isolated in the routine practice may be responsible for prostate infection in an undefined fraction of subjects. Anaerobic bacteria have been proposed to play a pathogenic role in CBP, on the basis of studies describing clinical remission after eradication of pathogens like Peptostreptococcus spp or Bacterioides spp from prostatic secretions of symptomatic patients, or the significant association between prostatic infection by anaerobes and the presence of inflammation markers in prostatic secretions.In this paper, we report in detail a case of severely symptomatic chronic prostatitis in a patient with evidence of infection by Peptostreptococcus. We also report for the first time that treatment with the 3rd generation fluoroquinolone moxifloxacin was successful in eradicating the pathogen and in causing dramatic resolution of signs and symptoms of chronic bacterial prostatitis.The strict association between eradication of Peptostreptococcus and the rapid disappearance of clinical signs/symptoms points to a causative role of this anaerobe in the chronic bacterial prostatitis case described in this report. 相似文献
76.
77.
Tiziana Greggi Konstantinos Martikos Emanuela Pipitone Francesco Lolli Francesco Vommaro Elena Maredi Stefano Cervellati Mario Di Silvestre 《Scoliosis》2010,5(1):1-11
Background
The reported incidence of scoliosis in arthrogryposis varies from 30% to 67% and, in most cases, the curves progress rapidly and become stiff from early age. The authors report six cases of scoliosis in arthrogryposis to assess the role of surgical treatment.Methods
Six cases (3 males, 3 females; mean age at surgery 13.2 years) with arthrogryposis multiplex congenita associated with the characteristic amyoplasia were reviewed: they were operated on for scoliosis at the authors' Spine Surgery Department between 1987 and 2008. Surgery was performed using the Harrington-Luque instrumentation (2 cases), the Luque system (1), a hybrid segmental technique with hooks and screws (1) and spinal anchoring with pedicle screws (2).Results
The patients were clinically and radiologically reviewed at a mean follow-up of 4.2 years, ± 2.7 (range, 1 to 9 years). Three minor postoperative complications were encountered; a long-term pulmonary complication was seen in one case after reintervention and was successfully resolved after 10 days. Surgery was successful in the other 5 cases, where solid arthrodesis was achieved and no significant curve progression was observed at follow-up.Conclusions
The experience acquired with the present case series leads the authors to assert that prompt action should be taken when treating such aggressive forms of scoliosis. In case of mild spinal deformities in arthrogryposis, brace treatment should be attempted, the evolution of the curves being unpredictable; however, when the curve exceeds 40° and presents with marked hyperkyphosis, hyperlordosis or pelvic obliquity, surgery should not be delayed. 相似文献78.
79.
Singh R Kaur B Kalina I Popov TA Georgieva T Garte S Binkova B Sram RJ Taioli E Farmer PB 《Mutation research》2007,620(1-2):71-82
Epidemiological studies conducted in metropolitan areas have demonstrated that exposure to environmental air pollution is associated with increases in mortality. Carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) are the major source of genotoxic activities of organic mixtures associated with respirable particulate matter, which is a constituent of environmental air pollution. In this study,we wanted to evaluate the relationship between exposure to these genotoxic compounds present in the air and endogenous oxidative DNA damage in three different human populations exposed to varying levels of environmental air pollution. As measures of oxidative DNA damage we have determined 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) by liquid chromatography–tandem mass spectrometry (LC–MS/MS) and cyclic pyrimidopurinone N-1,N2 malondialdehyde-2′-deoxyguanosine (M1dG) by the immunoslot blot assay from lymphocyte DNA of participating individuals. The level of endogenous oxidative DNA damage was significantly increased in individuals exposed to environmental air pollution compared to unexposed individuals from Kosice (8-oxodG adducts) and Sofia (M1dG adducts). However, there was no significant difference in the level of endogenous oxidative DNA and exposure to environmental air pollution in individuals from Prague (8-oxodG and M1dG adducts) and Kosice (M1dG adducts). The average level of M1dG adducts was significantly lower in unexposed and exposed individuals from Kosice compared to those from Prague and Sofia. The average level of 8-oxodG adducts was significantly higher in unexposed and exposed individuals from Kosice compared to those from Prague. A significant increasing trend according to the interaction of c-PAHs exposure and smoking status was observed in levels of 8-oxodG adducts in individuals from Kosice. However, no other relationship was observed for M1dG and 8-oxodG adduct levels with regard to the smoking status and c-PAH exposure status of the individuals. The conclusion that can be made from this study is that environmental air pollution may alter the endogenous oxidative DNA damage levels in humans but the effect appears to be related to the country where the individuals reside. Genetic polymorphisms of the genes involved in metabolism and detoxification and also differences in the DNA repair capacity and antioxidant status of the individuals could be possible explanations for the variation observed in the level of endogenous oxidative DNA damage for the different populations. 相似文献
80.
Pedemonte N Caci E Sondo E Caputo A Rhoden K Pfeffer U Di Candia M Bandettini R Ravazzolo R Zegarra-Moran O Galietta LJ 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(8):5144-5153
SCN(-) (thiocyanate) is an important physiological anion involved in innate defense of mucosal surfaces. SCN(-) is oxidized by H(2)O(2), a reaction catalyzed by lactoperoxidase, to produce OSCN(-) (hypothiocyanite), a molecule with antimicrobial activity. Given the importance of the availability of SCN(-) in the airway surface fluid, we studied transepithelial SCN(-) transport in the human bronchial epithelium. We found evidence for at least three mechanisms for basolateral to apical SCN(-) flux. cAMP and Ca(2+) regulatory pathways controlled SCN(-) transport through cystic fibrosis transmembrane conductance regulator and Ca(2+)-activated Cl(-) channels, respectively, the latter mechanism being significantly increased by treatment with IL-4. Stimulation with IL-4 also induced the strong up-regulation of an electroneutral SCN(-)/Cl(-) exchange. Global gene expression analysis with microarrays and functional studies indicated pendrin (SLC26A4) as the protein responsible for this SCN(-) transport. Measurements of H(2)O(2) production at the apical surface of bronchial cells indicated that the extent of SCN(-) transport is important to modulate the conversion of this oxidant molecule by the lactoperoxidase system. Our studies indicate that the human bronchial epithelium expresses various SCN(-) transport mechanisms under resting and stimulated conditions. Defects in SCN(-) transport in the airways may be responsible for susceptibility to infections and/or decreased ability to scavenge oxidants. 相似文献