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Marcello Mancini Adelaide Greco Enrico Tedeschi Giuseppe Palma Monica Ragucci Maria Grazia Bruzzone Anna Rita Daniela Coda Enza Torino Alessandro Scotti Ileana Zucca Marco Salvatore 《PloS one》2015,10(6)
To characterize the anatomy of the venous outflow of the mouse brain using different imaging techniques. Ten C57/black male mice (age range: 7-8 weeks) were imaged with high-frequency Ultrasound, Magnetic Resonance Angiography and ex-vivo Microcomputed tomography of the head and neck. Under general anesthesia, Ultrasound of neck veins was performed with a 20MHz transducer; head and neck Magnetic Resonance Angiography data were collected on 9.4T or 7T scanners, and ex-vivo Microcomputed tomography angiography was obtained by filling the vessels with a radiopaque inert silicone rubber compound. All procedures were approved by the local ethical committee. The dorsal intracranial venous system is quite similar in mice and humans. Instead, the mouse Internal Jugular Veins are tiny vessels receiving the sigmoid sinuses and tributaries from cerebellum, occipital lobe and midbrain, while the majority of the cerebral blood, i.e. from the olfactory bulbs and fronto-parietal lobes, is apparently drained through skull base connections into the External Jugular Vein. Three main intra-extracranial anastomoses, absent in humans, are: 1) the petrosquamous sinus, draining into the posterior facial vein, 2) the veins of the olfactory bulb, draining into the superficial temporal vein through a foramen of the frontal bone 3) the cavernous sinus, draining in the External Jugular Vein through a foramen of the sphenoid bone. The anatomical structure of the mouse cranial venous outflow as depicted by Ultrasound, Microcomputed tomography and Magnetic Resonance Angiography is different from humans, with multiple connections between intra- and extra- cranial veins. 相似文献
64.
Chiara Ciaccio Francisco Oca?a-Calahorro Enrica Droghetti Grazia R. Tundo Emanuel Sanz-Luque Fabio Polticelli Paolo Visca Giulietta Smulevich Paolo Ascenzi Massimo Coletta 《PloS one》2015,10(5)
The single-cell green alga Chlamydomonas reinhardtii harbors twelve truncated hemoglobins (Cr-TrHbs). Cr-TrHb1-1 and Cr-TrHb1-8 have been postulated to be parts of the nitrogen assimilation pathway, and of a NO-dependent signaling pathway, respectively. Here, spectroscopic and reactivity properties of Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4, all belonging to clsss 1 (previously known as group N or group I), are reported. The ferric form of Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4 displays a stable 6cLS heme-Fe atom, whereas the hexa-coordination of the ferrous derivative appears less strongly stabilized. Accordingly, kinetics of azide binding to ferric Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4 are independent of the ligand concentration. Conversely, kinetics of CO or NO2− binding to ferrous Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4 are ligand-dependent at low CO or NO2− concentrations, tending to level off at high ligand concentrations, suggesting the presence of a rate-limiting step. In agreement with the different heme-Fe environments, the pH-dependent kinetics for CO and NO2−binding to ferrous Cr-TrHb1-1, Cr-TrHb1-2, and Cr-TrHb1-4 are characterized by different ligand-linked protonation events. This raises the question of whether the simultaneous presence in C. reinhardtii of multiple TrHb1s may be related to different regulatory roles. 相似文献
65.
Di Gioia D Luziatelli F Negroni A Ficca AG Fava F Ruzzi M 《Journal of biotechnology》2010,156(4):309-316
Vanillin is one of the most important flavors in the food industry and there is great interest in its production through biotechnological processes starting from natural substrates such as ferulic acid. Among bacteria, recombinant Escherichia coli strains are the most efficient vanillin producers, whereas Pseudomonas spp. strains, although possessing a broader metabolic versatility, rapidly metabolize various phenolic compounds including vanillin. In order to develop a robust Pseudomonas strain that can produce vanillin in high yields and at high productivity, the vanillin dehydrogenase (vdh)-encoding gene of Pseudomonas fluorescens BF13 strain was inactivated via targeted mutagenesis. The results demonstrated that engineered derivatives of strain BF13 accumulate vanillin if inactivation of vdh is associated with concurrent expression of structural genes for feruloyl-CoA synthetase (fcs) and hydratase/aldolase (ech) from a low-copy plasmid. The conversion of ferulic acid to vanillin was enhanced by optimization of growth conditions, growth phase and parameters of the bioconversion process. The developed strain produced up to 8.41 mM vanillin, which is the highest final titer of vanillin produced by a Pseudomonas strain to date and opens new perspectives in the use of bacterial biocatalysts for biotechnological production of vanillin from agro-industrial wastes which contain ferulic acid. 相似文献
66.
Corrente M Franchini D Decaro N Greco G D'Abramo M Greco MF Latronico F Crovace A Martella V 《The new microbiologica》2010,33(4):337-341
Brucella spp. is a worldwide zoonotic pathogen. Infection by Brucella canis in dogs is endemic in the Southern USA and in Central and South America, but it appears sporadically in other parts of the world, including Europe. Tissue samples from a dog with chronic prostatitis, discospondylitis and locomotor problems were subjected to clinical and laboratory examinations. B. canis was detected by PCR in biological fluids and tissues of the animal, while antibodies to B. canis were found in the serum, providing additional strong evidence for the circulation of B. canis in Italy. 相似文献
67.
Zhenrong Xu Salvacion Cacatian Jing Yuan Robert D. Simpson Lanqi Jia Wei Zhao Colin M. Tice Patrick T. Flaherty Joan Guo Alexey Ishchenko Suresh B. Singh Zhongren Wu Brian M. McKeever Boyd B. Scott Yuri Bukhtiyarov Jennifer Berbaum Jennifer Mason Reshma Panemangalore Maria Grazia Cappiello Ross Bentley David A. Claremon 《Bioorganic & medicinal chemistry letters》2010,20(2):694-699
Structure-guided drug design led to new alkylamine renin inhibitors with improved in vitro and in vivo potency. Lead compound 21a, has an IC50 of 0.83 nM for the inhibition of human renin in plasma (PRA). Oral administration of 21a at 10 mg/kg resulted in >20 h reduction of blood pressure in a double transgenic rat model of hypertension. 相似文献
68.
Nicoletta Botto Simona Vittorini Giovanna Maria Colombo Andrea Biagini Umberto Paradossi Giovanni Aquaro Maria Grazia Andreassi 《Cardiovascular ultrasound》2010,8(1):1-5
Background
To assess the reliability of fetal heart volume measurement by three-dimensional sonography (3DUS) using the eXtended Imaging Virtual Organ Computer-aided AnaLysis (XI VOCAL) method.Methods
This reliability study enrolled 30 pregnant women with singleton healthy pregnancies between 19 and 34 weeks of gestation. All volume acquirements were performed with a convex volumetric transducer (C3-7ED) coupled to an Accuvix XQ sonography device (Medison, Korea). The XI VOCAL 10 planes was the method of choice for volumetric measurement. 3D datasets were analyzed by two observers (EQSB and HJFM); fetal heart volume was measured twice by the first and once by the second observer to calculate intra and interobserver reproducibility. Statistical analysis used pareated Student's t test (p) and calculated Intraclass correlation coefficients (ICC). Bland-Altman plots were also constructed.Results
We observed an excellent intra- and interobserver reliability for fetal cardiac volume assessed by XI VOCAL. For the intraobserver the ICC was 0.998 (95% CI: 0.997; 0.999), with mean of differences of 0.12 cm3 (95% limits of agreement: -0.84; +0.84; p = 0.130). For interobserver the ICC was 0.899 (95%CI: 0.996; 0.998), mean of differences 0.05 cm3 (95% limits of agreement: -0.84; +0.84; p = 0.175).Conclusion
Fetal cardiac volume assessed by 3DUS using XI VOCAL method is highly reproducible between 19 to 34 gestational weeks. 相似文献69.
Manfredi S Federici C Picano E Botto N Rizza A Andreassi MG 《Mutation research》2007,621(1-2):106-112
Cigarette smoking is a powerful risk factor for coronary artery disease (CAD), leading to the formation of DNA alterations within blood vessels and heart. However, the degree of smoking-related atherosclerosis varies from individual to individual. Genetic polymorphisms of relevant xenobiotic metabolising enzymes may determine the susceptibility of an individual response to environmental toxicants. The purpose of this study was to test the hypothesis that the inheritance of polymorphic genes encoding cytochrome P450 1A1 (CYP1A1 MspI) and glutathione S-transferases (GSTM1(null) and GSTT1(null)) may be causally associated with the presence and severity of smoking-induced CAD. In a case-only design, 222 (179 male, 57.8+/-10.3 years) consecutive smoker patients who had undergone elective and diagnostic coronary angiography were recruited. We found a group (n=169) of smoker patients with significant CAD, defined as>50% reduction in diameter of at least one major vessel, and a group without obstructive CAD (n=53). No significant differences were observed in CYP1A1 genotypes frequencies between CAD and non-CAD smokers (p=0.1). Homozygous deletion of GSTM1 had a frequency of 58.6% among patients with CAD and 45.3% among those without CAD (p=0.08). The frequency of the GSTT1(null) genotype was 43.8% among the patients with CAD and 24.5% among CAD-free subjects (p=0.01). After adjustment for traditional risk factors, the presence of combined GSTM1(null)GSTT1(null) genotypes was significantly associated with an increased risk of CAD (OR=3.9; 95% CI: 1.3-11.4, p=0.01). Moreover, smokers with combined GSTM1(null)GSTT1(null) genotypes had significantly higher number of stenosed vessels than those with the positive genotype (2.3+/-0.9 versus 1.7+/-0.8, p=0.03). Our findings showed that smokers carrying GST deleted genotypes have an increased susceptibility to the smoking related coronary artery disease. Exploring gene-smoking effect provides an excellent model in order to understand gene-environment toxicants interaction and its implications to cardiovascular disease. 相似文献
70.
Diagnostic cardiac ultrasounds are an environment-friendly and non-ionising imaging technology. However, ultrasounds are not biologically inert, and their use might have profound clinical impact. This paper summarizes the known effects of cardiac ultrasound—compared to other major imaging techniques—to exposed patients and to clinically exposed physicians practising ultrasound imaging. Furthermore, this review also provides an overview of the evidences on the biological effects of diagnostic ultrasound—which suggest that ultrasound with frequency, intensity and duration fully in the diagnostic range have significant molecular, cellular and organ effects.
A better understanding of these effects may improve our understanding of the complex interactions between ultrasound and biological tissues and may open new avenues to therapeutic applications based on the ultrasound-modulated cell functions, such as membrane transduction, apoptosis, cell permeability and thrombolysis. 相似文献