Effect of exogenous proline on the ethanolic tolerance and malolactic performance of Oenococcus oeni

The use of malolactic starter cultures, often offer no guarantee of microbiological success due to the chemical and physical factors (pH, ethanol, SO₂, nutrient availability) that occur during the winemaking process. This study was born with the aim of improving the performance of the lactic acid bacteria used as a starter culture in the de-acidification of wines. Two commercial strains of Oenococcus oeni, were used. Was evaluated the effect of exogenous l-proline added during the bacterial growth, on the improvement of their survival in the presence of different ethanol concentrations and their ability to degrade l-malic acid in synthetic wine with the presence of 12% (v/v) and 13% (v/v) of ethanol. The results showed that l-proline improve ethanol tolerance and so the malolactic performances of O. oeni. This work represents an important strategy to ensure good vitality and improve the performance of the malolactic starter.

Red wine activates plasma membrane redox system in human erythrocytes

In the present study, we report that polyphenols present in red wine obtained by a controlled microvinification process are able to protect human erythrocytes from oxidative stress and to activate Plasma Membrane Redox System (PMRS). Human plasma obtained from healthy subjects was incubated in the presence of whole red wine at a concentration corresponding to 9.13-73 μg/ml gallic acid equivalents to verify the capacity to protect against hypochlorous acid (HOCl)-induced plasma oxidation and to minimize chloramine formation. Red wine reduced hemolysis and chloramine formation induced by HOCl of 40 and 35%, respectively. PMRS present on human erythrocytes transfers electrons from intracellular molecules to extracellular electron acceptors. We demonstrated that whole red wine activated PMRS activity in human erythrocytes isolated from donors in a dose-dependent manner with a maximum at about 70-100 μg/ml gallic acid equivalents. We also showed that red wine increased glutathione (GSH) levels and erythrocytic antioxidant capacity, measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) quenching assay. Furthermore, we reported that GSH played a crucial role in regulating PMRS activity in erythrocytes. In fact, the effect of iodoacetamide, an alkylating agent that induces depletion of intracellular GSH, was completely counteracted by red wine. Bioactive compounds present in red wine, such as gallic acid, resveratrol, catechin, and quercetin were unable to activate PMRS when tested at the concentrations normally present in aged red wines. On the contrary, the increase of PMRS activity was associated with the anthocyanin fraction, suggesting the capacity of this class of compounds to positively modulate PMRS enzymatic activity.

Effect of winemaking practices on color indexes and selected bioactive phenolics of Aglianico wine

Phenolic compounds are responsible for the sensory properties of wine as well as the properties beneficial to human health. The objective of this study was to establish the effect of the use of SO2 and pectolitic enzymes in the prefermentative phase, maceration time, and oak aging on color, anthocyanins, tannins, (+)-catechin, (-)-epicatechin, rutin, trans-resveratrol, and quercetin content of Aglianico wine. Color indexes and phenolics were analyzed by HPLC and spectrophotometric methods. The addition of SO2 and pectolitic enzymes before fermentation caused an increase in color intensity, color stability, total phenolics, anthocyanins, (+)-catechin, (-)-epicatechin rutin, trans-resveratrol, and quercetin content in Aglianico wine. Longer maceration times gave wines richer in total phenolics and with better chromatic characteristics. Storage in oak caused a decrease in anthocyanins, (+)-catechin, (-)-epicatechin, trans-resveratrol, and quercetin content but an increase in total phenolic content, and a stabilizing effect on color also occurred.

trans-Resveratrol, quercetin, (+)-catechin, and (-)-epicatechin content in south Italian monovarietal wines: relationship with maceration time and marc pressing during winemaking

The concentrations of trans-resveratrol, (+)-catechin, (-)-epicatechin, and quercetin were evaluated by means of high-performance liquid chromatography-diode array detection in red wines obtained from Aglianico, Piedirosso, and Nerello Mascalese grapes. The trans-resveratrol and epicatechin concentrations did not differ significantly between experimental wines. The concentration of quercetin in Nerello Mascalese wines was more than twice that observed in Aglianico and Piedirosso wines. Nerello Mascalese wines also significantly differed from other wines in the (+)-catechin content, which was significantly higher than those found in the other two wines. During maceration, the maximum extraction of trans-resveratrol was reached after 12 days for Aglianico and Piedirosso, after which a decline was observed. On the contrary, in the case of Nerello Mascalese, the concentration of trans-resveratrol increased steadily throughout the whole maceration process. After 2 days of maceration, the maximum concentration of quercetin was observed in Aglianico must, whereas the maximum quercetin extraction was reached after 12 days for Piedirosso and 17 days for Nerello Mascalese. The maximum levels of (+)-catechin and (-)-epicatechin were generally observed after 12 days of maceration for all wines, although a decline of (-)-epicatechin occurred after maximum extraction in Aglianico and Piedirosso wines. Following marc pressing, a significant increase in the concentration of trans-resveratrol for Aglianico, (+)-catechin and (-)-epicatechin for Piedirosso, and (-)-epicatechin for Nerello Mascalese was observed.

Clostridium innocuum bacteremia secondary to infected hematoma with gas formation in a kidney transplant recipient

Clostridium innocuum is a relatively antimicrobial resistant, frequently misidentified anaerobe that has only rarely been associated with bacteremia. A 38-year-old female with chronic hepatitis C underwent a second kidney transplant operation. Two weeks after surgery a computed tomography scan of the abdomen showed a heterogeneous hematoma with pockets of gas adjacent to the allograft, which extended into the pelvis and left abdominal wall, associated with low-grade fever. An anaerobic blood culture grew a Clostridium initially identified as C. subterminale and later re-identified as C. innocuum. At abdominal exploration liquefied blood was evacuated, and the patient completed a course of antibiotics and recovered. C. innocuum should be considered as a cause of gas-producing anaerobic infection in transplant patients. Because C. innocuum is frequently misidentified by the use of commercial anaerobic identification kits, its true incidence in serious infections is likely underestimated.

Whole-body FDG positron emission tomographic imaging for staging esophageal cancer comparison with computed tomography

PURPOSE

The aim of the authors in this study was to critically evaluate the role of whole-body positron emission tomographic (PET) imaging with fluorine-18 fluorodeoxyglucose (FDG) in staging esophageal cancer, and further to compare this method with conventional imaging with computed tomography (CT).

MATERIALS AND METHODS

The authors performed independent, blinded retrospective evaluations of FDG PET images obtained in 47 patients referred for the initial staging of esophageal cancer before minimally invasive surgical staging. Twenty PET studies from patients with nonesophageal thoracic cancers were randomly selected for inclusion in the PET readings. In a subset of 37 of 47 cases, the PET findings were compared with independent readings of CT studies acquired within the same 6-week interval. The utility of the imaging findings was evaluated using a high-sensitivity interpretation (i.e., assigning equivocal findings as positive) and a low-sensitivity interpretation (i.e., assigning equivocal findings as negative).

RESULTS

PET was less sensitive (41% in high-sensitivity mode, 35% in low-sensitivity mode) than CT (63% to 87%) for diagnosing tumor involvement in locoregional lymph nodes, which was identified by surgical assessment in 72% of patients. Notable, however, was the greater specificity of PET-determined nodal sites (to approximately 90%) compared with CT (14% to 43%). In detecting histologically proved distant metastases (n = 10), PET performed considerably better when applied in the high-sensitivity mode, with a sensitivity rate of approximately 70% and a specificity rate of more than 90% in the total group and in the subset of patients with correlative CT data. In the low-sensitivity mode, CT identified only two of seven metastatic sites, whereas the high-sensitivity mode resulted in an unacceptably high rate of false-positive readings (positive predictive value, 29%). PET correctly identified one additional site of metastasis that was not detected by CT.

CONCLUSIONS

The relatively low sensitivity of PET for identifying locoregional lesions precludes its replacement of conventional CT staging. However, the primary advantage of PET imaging is its superior specificity for tumor detection and improved diagnostic value for distant metastatic sites, features that may substantially affect patient management decisions. In conclusion, PET imaging is useful in the initial staging of esophageal cancer and provides additional and complementary information to that obtained by CT imaging.

A comparison of techniques for placement of double-lumen endobronchial tubes

STUDY OBJECTIVE

To compare two methods of double-lumen endobronchial tube placement for thoracic surgery and to identify factors that provide a rational basis for placement method selection.

DESIGN

Prospective, randomized study.

SETTING

Teaching hospital.

PATIENTS

58 ASA physical status II, III, and IV patients scheduled for surgical procedures requiring elective left-sided endobronchial intubation.

INTERVENTIONS

Patients were assigned randomly to either a group in which the initial placement method was the traditional approach of placing the endobronchial tube through the larynx and then advanced blindly into the left mainstem bronchus, or to a second group in which the left mainstem bronchus was intubated under direct vision using the fiberoptic bronchoscope.

MEASUREMENTS AND MAIN RESULTS

Of the 32 patients who underwent the traditional approach, primary success occurred in 27 patients and eventual success in 30. In 27 patients undergoing the directed approach, primary success occurred in 21 patients and eventual success in 25. Two patients in each group required the alternative method. The blind approach took 88 (+/- 91) seconds and the directed approach took 181 (+/- 193) seconds (p = 0.029). Timing data were analyzed using analysis of variance with respect to method and secretions and then t-tests as appropriate. Categorical data were analyzed using the Kruskal-Wallis and Fisher's exact tests as appropriate. All values are reported as means +/- SD.

CONCLUSION

Both the blind and directed approaches resulted in successful left mainstem placement of the endobronchial tube in the majority of patients but either method may fail when used alone. More time was required using the directed approach. Operator experience with both methods will increase the likelihood of success. The choice of the initial approach may be influenced by patient factors as well as available equipment and personnel.