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991.
The volatile components of grape pomace coming from the processing of some of the most important varieties of grape (Vitis vinifera L.) cultivated in Sicily, namely Nero d'Avola, Nerello Mascalese, Frappato and Cabernet Sauvignon, have been determined by gas-chromatography (GC) and gas-chromatography-mass spectrometry (GC-MS). According to the winemaking procedure that entails the removal of stalks before fermentation, two kinds of grape pomace are obtained. The first consists of skins, pulp residues and seeds, the proper grape pomace, which is partially used for grappa, a typical Italian spirit, and alcohol production, the second consists almost exclusively of stalks. On the whole, 38 components have been characterized in the samples of grape pomaces, with Frappato cv. showing the richest composition; instead, 88 components have been detected in the stalks of Frappato, Nero d'Avola, Nerello Mascalese and Cabernet Sauvignon varieties. In order to make a comparison between the grape varieties easier, the volatile components detected in the two sets of samples (grape pomaces and stalks) have been grouped in different classes. Significant differences among varieties have been detected and statistical treatment of data is also reported. This study is part of a wider project aimed at the possible exploitation of the main agro-industrial by-products. At the same time it is one of the first reports on the volatile components of this waste material. 相似文献
992.
Two Cases of Vaginitis Caused by Itraconazole-Resistant Saccharomyces cerevisiae and a Review of Recently Published Studies 总被引:1,自引:0,他引:1
Savini V Catavitello C Manna A Talia M Febbo F Balbinot A D'Antonio F Di Bonaventura G Celentano C Liberati M Piccolomini R D'Antonio D 《Mycopathologia》2008,166(1):47-50
Genitourinary infections caused by non-Candida yeasts are uncommon, and especially due to Saccharomyces cerevisiae. We describe the cases of two adult females with vulvovaginal infections caused by itraconazole-resistant S. cerevisiae who made a full recovery after oral fluconazole therapy. We also provide a concise review of recently published studies on this topic. 相似文献
993.
Bernini A Venditti V Spiga O Ciutti A Prischi F Consonni R Zetta L Arosio I Fusi P Guagliardi A Niccolai N 《Biophysical chemistry》2008,137(2-3):71-75
Understanding how proteins are approached by surrounding molecules is fundamental to increase our knowledge of life at atomic resolution. Here, the surface accessibility of a multifunctional small protein, the archaeal protein Sso7d from Sulfolobus solfataricus, has been investigated by using TEMPOL and Gd(III)(DTPA-BMA) as paramagnetic probes. The DNA binding domain of Sso7d appears very accessible both to TEMPOL and Gd(III)(DTPA-BMA). Differences in paramagnetic attenuation profiles of (1)H-(15)N HSQC protein backbone amide correlations, observed in the presence of the latter paramagnetic probes, are consistent with the hydrogen bond acceptor capability of the N-oxyl moiety of TEMPOL to surface exposed Sso7d amide groups. By using the gadolinium complex as a paramagnetic probe a better agreement between Sso7d structural features and attenuation profile is achieved. It is interesting to note that the protein P-loop region, in spite of the high surface exposure predicted by the available protein structures, is not approached by TEMPOL and only partially by Gd(III)(DTPA-BMA). 相似文献
994.
The T-cell receptor (TCR) signalling machinery is central in determining the response of a T cell (establishing immunity or tolerance) following exposure to antigen. This process is made difficult by the narrow margin of self and non-self discrimination, and by the complexity of the genetic programmes that are induced for each outcome. Recent studies have identified novel negative feedback mechanisms that are rapidly induced by TCR engagement and that have key roles in the regulation of signal triggering and propagation. In vitro and in vivo data suggest that they are important in determining ligand discrimination by the TCR and in regulating signal output in response to antigen. 相似文献
995.
Tonino Bombardini Vincenzo Gemignani Elisabetta Bianchini Lucia Venneri Christina Petersen Emilio Pasanisi Lorenza Pratali David Alonso-Rodriguez Mascia Pianelli Francesco Faita Massimo Giannoni Giorgio Arpesella Eugenio Picano 《Cardiovascular ultrasound》2008,6(1):1-20
A cutaneous force-frequency relation recording system based on first heart sound amplitude vibrations has been recently validated. Second heart sound can be simultaneously recorded in order to quantify both systole and diastole duration.
Aims
1- To assess the feasibility and extra-value of operator-independent, force sensor-based, diastolic time recording during stress.Methods
We enrolled 161 patients referred for stress echocardiography (exercise 115, dipyridamole 40, pacing 6 patients). The sensor was fastened in the precordial region by a standard ECG electrode. The acceleration signal was converted into digital and recorded together with ECG signal. Both systolic and diastolic times were acquired continuously during stress and were displayed by plotting times vs. heart rate. Diastolic filling rate was calculated as echo-measured mitral filling volume/sensor-monitored diastolic time.Results
Diastolic time decreased during stress more markedly than systolic time. At peak stress 62 of the 161 pts showed reversal of the systolic/diastolic ratio with the duration of systole longer than diastole. In the exercise group, at 100 bpm HR, systolic/diastolic time ratio was lower in the 17 controls (0.74 ± 0.12) than in patients (0.86 ± 0.10, p < 0.05 vs. controls). Diastolic filling rate increased from 101 ± 36 (rest) to 219 ± 92 ml/m2* s-1 at peak stress (p < 0.5 vs. rest).Conclusion
Cardiological systolic and diastolic duration can be monitored during stress by using an acceleration force sensor. Simultaneous calculation of stroke volume allows monitoring diastolic filling rate. Stress-induced "systolic-diastolic mismatch" can be easily quantified and is associated to several cardiac diseases, possibly expanding the spectrum of information obtainable during stress. 相似文献996.
Giuffrida A Tabera L González R Cucinotta V Cifuentes A 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,875(1):243-247
Autolysis of Saccharomyces cerevisiae yeast is the main source of molecules that contribute to the quality of sparkling wines made by the traditional method. In this work, a genetically modified yeast (LS11) is compared to its isogenic wild type strain (BY4741) after autolysis. Chiral micellar electrokinetic chromatography with laser-induced fluorescence detection (chiral-MEKC-LIF) is used to identify and quantify the main D- and L-amino acids from both strains after accelerated autolysis. The procedure includes amino acids extraction, derivatization with FITC and chiral-MEKC-LIF separation in a background electrolyte composed of 100 mM sodium tetraborate, 30 mM SDS, 20 mM beta-CD at pH 10.0. The D- and L-forms of Arg, Asn, Ala, Glu and Asp, corresponding to the major amino acids found in these samples, are separated in less than 30 min with efficiencies up to 800,000 plates/m and high sensitivity (i.e., LODs as low as 40 nM were obtained for D-Arg for a signal to noise ratio of three). From these results it is corroborated that the genetic modification brings a faster autolysis of the yeast, releasing a higher amount of L-amino acids to the medium in a short time. Interestingly, the pattern of release of D-amino acids was also different between the transgenic and the conventional yeast strains. 相似文献
997.
The aim of this research is to investigate the relationship between obesity and wages, using data for nine countries from the European Community Household Panel (ECHP) over the period 1998-2001. We improve upon the existing literature by adopting a Quantile Regression approach to characterize the heterogenous impact of obesity at different points of the wage distribution. Our results show that (i) the evidence obtained from mean regression and pooled analysis hides a significant amount of heterogeneity as the relationship between obesity and wages differs across countries and wages quantiles and (ii) cultural, environmental or institutional settings do not seem to be able to explain differences among countries, leaving room for a pure discriminatory effect hypothesis. 相似文献
998.
999.
Lucattelli M Lunghi B Fineschi S Mirone V d'Emmanuele di Villa Bianca R Longo N Imbimbo C De Palma R Sorrentino R Lungarella G Cirino G 《The international journal of biochemistry & cell biology》2008,40(11):2638-2648
Peyronie's disease (PD) is characterized by an inflammatory response beneath the tunica albuginea with fibroblast proliferation forming a thickened fibrous plaque that may cause pain, penile curvature and erectile dysfunction. The progression of the PD plaque may eventually lead to calcification or ossification. Current therapeutic success is often unsatisfactory because of limited insight into disease mechanisms. Research has been hampered by the lack of a universally accepted animal model. We describe an animal model of spontaneous PD in tight skin (Tsk) mice, a C57Bl/6J subline that reproduces with age important features of the human disease (fibrous plaque formation, penile bending and areas of chondroid metaplasia with heterotopic ossification). Histological analysis demonstrated an evident structural disorganization of the tunica albuginea with excessive accumulation of type I collagen. At 12 months of age, fibrous plaques with areas of chondroid metaplasia and heterotopic ossification characterized Tsk penises. The up-regulation of hypoxia-inducible factor-1 (HIF-1) leads to an increased downstream expression of HIF-1 target genes, such as TGFbeta and iNOS. These factors, together with some PDGF family members, can cause collagen deposition in Tsk penises. They can also influence chondrocyte differentiation and heterotopic bone formation. In conclusion, hypoxia, HIF-1 and HIF-1 target genes appear to play an important role in the pathogenesis of PD in Tsk mice. This mouse model that is the first example of naturally occurring model of PD in laboratory animals may aid in the identification of signalling pathways crucial for PD and should facilitate the designing and testing of new therapeutic interventions. 相似文献
1000.
Adrenocorticotropic hormone and cortisol plasma levels directly correlate with childhood neglect and depression measures in addicted patients. 总被引:1,自引:0,他引:1
Gilberto Gerra Claudio Leonardi Elena Cortese Amir Zaimovic Grazia Dell'Agnello Matteo Manfredini Lorenzo Somaini Francesca Petracca Vincenzo Caretti Cristina Baroni Claudio Donnini 《Addiction biology》2008,13(1):95-104
Hypothalamic-pituitary-adrenal (HPA) axis dysfunction has been reported to be involved in vulnerability to alcohol and drug dependence in humans, possibly underlying both addictive behaviour and depression susceptibility. The aim of the present study was to investigate the possible interactions between childhood adverse experiences, depressive symptoms and HPA axis function in addicted patients, in comparison with healthy control. Eighty-two abstinent heroin or cocaine dependent patients and 44 normal controls, matched for age and sex, completed the symptoms Check List-90 (SCL-90), measuring depressive symptoms, and the Childhood Experience of Care and Abuse Questionnaire. Blood samples were collected to determine adrenocorticotropic hormone (ACTH) and cortisol basal plasma levels at 8:00 and 8:30 a.m. Addicted individuals showed significantly higher neglect and depression scores and ACTH-cortisol plasma levels respect to control subjects. Depression scores at SCL-90 in addicted patients positively correlated with plasma ACTH and cortisol values. In turn, plasma ACTH levels were directly associated with childhood neglect measures, reaching statistical significance with 'mother-neglect' scores. Plasma cortisol levels were related to 'father antipathy' among cocaine addicts. These findings suggest the possibility that childhood experience of neglect and poor parent-child attachment may have a persistent effect on HPA axis function as an adult, partially contributing, together with genetic factors and other environmental conditions, to both depressive traits and substance abuse neurobiological vulnerability. 相似文献