Effect of red thyme oil (Thymus vulgaris L.) vapours on fungal decay, quality parameters and shelf-life of oranges during cold storage.

This work has been aimed at studying the effect of red thyme oil (RTO, Thymus vulgaris L.) on the shelf-life and Penicillium decay of oranges during cold storage. RTO vapours significantly reduced (P ≤ 0.05) the percentage of infected wounds, the external growth area and the production of spores in inoculated orange fruit stored for 12 days at 7 °C in a polypropylene film selected for its appropriate permeability. Among the RTO compounds, p-cymene and thymol were the most abundant in packed boxes at the end of cold storage. The RTO vapours did not affect the main quality parameters of the oranges, or the taste and odour of the juice. The results have shown that an active packaging, using RTO vapours, could be employed, by the citrus industry, to extend the shelf-life of oranges for fresh market use and juice processing.

Growth and metabolite production of a grape sour rot yeast-bacterium consortium on different carbon sources.

The present study was designed to evaluate possible sugar-based trophic interactions between acetic acid bacteria (AAB) and non-Saccharomyces yeasts (NSY) involved in table grape sour rot, a disease in which berries spoilage is caused by the accumulation of several microbial metabolites. Acetobacter syzygii LMG 21419 (As) and Candida zemplinina CBS 9494 (Cz), a simplified AAB-NSY association responsible for table grape sour rot, grew differently in a minimal medium (YP) supplemented with glucose, ethanol, acetic and gluconic acid under monoculture conditions. In As -Cz co-culture media, after 24 h of incubation, As showed high relative abundance in YP-ethanol, whereas Cz was the dominant strain in YP-glucose medium. Co-culture in YP-glucose showed that glucose was converted into ethanol by Cz that, in turn, promoted the growth of As population. Gluconic acid was the main bacterial metabolite from glucose in monoculture, whereas acetic acid putatively derived from ethanol oxidation was found only in co-culture. However, gluconic acid showed inhibitory effect against As whereas acetic acid mainly inhibited Cz. Negative effects of both metabolites were mitigated in the glucose-supplemented medium. The results suggest a possible metabolic- based temporal succession between AAB and NSY during grape sour rot development. At the begin of sour rot, low glucose concentration promotes NSY producing ethanol, then, the AAB could take advantage from the oxidation of ethanol into acetic acid, becoming the dominant microbial sour rot population during the late stages of the process.

Efficacy of gaseous ozone to counteract postharvest table grape sour rot.

This work aims at studying the efficacy of low doses of gaseous ozone in postharvest control of the table grape sour rot, a disease generally attributed to a consortium of non-Saccharomyces yeasts (NSY) and acetic acid bacteria (AAB). Sour rot incidence of wounded berries, inoculated with 8 NSYstrains, or 7 AAB, or 56 yeast-bacterium associations, was monitored at 25 °C up to six days. Sour rot incidence in wounded berries inoculated with yeast-bacterium associations resulted higher than in berries inoculated with one single NSY or AAB strain. Among all NSY-AAB associations, the yeast-bacterium association composed of Candida zemplinina CBS 9494 (Cz) and Acetobacter syzygii LMG 21419 (As) showed the highest prevalence of sour rot; thus, after preliminary in vitro assays, this simplified As-Cz microbial consortium was inoculated in wounded berries that were stored at 4 °C for ten days under ozone (2.14 mg m-3) or in air. At the end of cold storage, no berries showed sour-rot symptoms although ozonation mainly affected As viable cell count. After additional 12 days at 25 °C, the sour rot index of inoculated As-Cz berries previously cold-stored under ozone or in air accounted for 22.6 ± 3.7% and 66.7 ± 4.5%, respectively. Molecular analyses of dominant AAB and NSY populations of both sound and rotten berries during post-refrigeration period revealed the appearance of new strains mainly belonging to Gluconobacter albidus and Hanseniaspora uvarum species, respectively. Cold ozonation resulted an effective approach to extend the shelf-life of table grapes also after cold storage.

Pituitary apoplexy during pregnancy: a rare, but dangerous headache.

Pituitary apoplexy is a rare endocrine emergency that occurs in a small number of patients with a pituitary tumor. It is a clinical syndrome characterized by the sudden onset of headache, nausea, vomiting, visual impairment, and decreased consciousness, caused by hemorrhage and/or infarction of the pituitary gland. Pituitary apoplexy has very rarely been described during pregnancy, when it is potentially life-threatening to both the mother and the fetus, if unrecognized. Only a few cases have been published to date. The review of the existing literature underlines that pituitary apoplexy, although rare, should be borne in mind when a pregnant woman presents with severe headache and visual defects of sudden onset. After initial management, which includes intravenous glucocorticoid therapy, fluid and electrolyte replacement, the final selection of medical or surgical treatment should result from a multidisciplinary approach involving expert specialists, keeping into account both severity of clinical presentation and gestational week.

Changes in bacterial composition of zucchini flowers exposed to refrigeration temperatures.

Microbial spoilage is one of the main factors affecting the quality of fresh fruits and vegetables, leading to off-flavor, fermented aroma, and tissue decay. The knowledge of microbial growth kinetics is essential for estimating a correct risk assessment associated with consuming raw vegetables and better managing the development of spoilage microorganisms. This study shows, for the first time, that only a part of total microbial community, originally present on fresh harvested female zucchini flowers, was able to adapt itself to refrigerated conditions. Through the study of microbial growth kinetics it was possible to isolate forty-four strains belonging to twenty-two species of the genera Acinetobacter, Arthrobacter, Bacillus, Enterobacter, Erwinia, Klebsiella, Pantoea, Pseudoclavibacter, Pseudomonas, Serratia, Staphylococcus, and Weissella, suggesting Enterobacteriaceae as potentially responsible for pistil spoilage.

Biotransformation of patulin by Gluconobacter oxydans.

A bacterium isolated from patulin-contaminated apples was capable of degrading patulin to a less-toxic compound, ascladiol. The bacterium was identified as Gluconobacter oxydans by 16S rRNA gene sequencing, whereas ascladiol was identified by liquid chromatography-tandem mass spectrometry and proton and carbon nuclear magnetic resonance. Degradation of up to 96% of patulin was observed in apple juices containing up to 800 microg/ml of patulin and incubated with G. oxydans.

Plasma radio-frequency-based diskectomy for treatment of cervical herniated nucleus pulposus: feasibility, safety, and preliminary clinical results.

BACKGROUND AND PURPOSE: Several techniques, including chymopapain, mechanical aspiration, laser-based disk decompression, and endoscopic keyhole surgery, have been proposed as minimally invasive alternatives to fusion for treating cervical disk herniation, though none has gained wide acceptance. The purpose of this study was to assess feasibility, safety, and preliminary clinical results of percutaneous plasma-mediated radio-frequency-based diskectomy for cervical disk herniation. METHODS: Patients (N = 55) with cervical soft disk protrusion were treated over a 29-month period. They had radicular pain; 3 patients also had moderate myelopathy. The procedure was performed with the Perc-DC SpineWand by using an anterior approach. Most cases were conducted with local anesthetic on an outpatient basis. Clinical outcomes were graded by using the Macnab criteria. RESULTS: At 2 months, outcomes were good or excellent in 44/55 (80%) patients; the success rate was similar at 6 months, when 44 (85%) patients (n = 52/55) had good or excellent results. One clinically relevant complication (infectious diskitis) occurred within the first month postprocedure and was successfully treated. One technical complication (in situ rupture of the device tip) was observed; however, the patient remained asymptomatic during the 2-year follow-up. The 3 patients with clinical myelopathy experienced regression of cord compression symptoms; MR imaging in 2 patients showed morphologic evidence of reduction of cord compression. CONCLUSIONS: Plasma radio-frequency-based diskectomy in the cervical spine appears to be a minimally invasive low-risk approach, which is easy to perform, associated with only minimal discomfort to the patient, and effective in the short term.

Angioplasty and stenting of the cervical carotid bifurcation under filter protection: a prospective study in a series of 53 patients.

The aim of this study is to assess safety, reliability, ease of use and usefulness of filter protection devices during angioplasty and stenting of stenotic lesions of the cervical carotid bifurcation. Over a period of 42 months, 53 patients harboring a cervical carotid bifurcation stenotic lesion were treated, by angioplasty and/or stenting using filter protection devices of different kinds. The stenosis was atherosclerotic in 48 cases, post-surgical in four and post-radiation in one case. In all cases, the treatment was successful, with good restoration of the luminal diameter. There were three major strokes (5.6%) and one minor stroke (1.9%). Two of these (one major, one minor) occurred a few hours after the stenting procedure and both seemed by all evidence due to a hemorrhagic hyperperfusion syndrome. One hemiparesis and dysphasia occurred two days after the procedure, secondary to subacute thrombosis with occlusion of the stent. One patient complained of three episodes of decrease in visual acuity of the eye ipsilateral to the stenting in the two weeks following treatment. In conclusion, in our experience, use of the devices adds only few minutes to the procedure time; direct lesions of the arterial wall, such as dissections or intraluminal thrombi, related to the use of filters were never observed, and spasm of the distal I.C.A. also proved rapidly regressive. The content of all filters, if any, was histologically examined, but plaque material was found only in one case, probably owing to our primary stenting technique without use of pre-dilation. The major technical drawback is in-filter coagulation, which occurred in 16 cases, occluding the membrane of the filter and thus slowing or blocking intracranial flow. Such an event can be counteracted by a more aggressive anti-coagulation protocol, which could, however, be responsible for the two complications with hemorrhagic brain infarction. Furthermore, we observed two other major neurological events, which bring the incidence of neurological complications in this series as high as 7.5%. Therefore, it is our opinion that safety of filters is not yet proven, and consequently great care must be taken in their use.

Microbial community dynamics during the Scamorza Altamurana cheese natural fermentation.

The growth dynamics of the natural microbial community responsible for the fermentation of Scamorza Altamurana, a typical Southern Italian cheese made using backslopping, was investigated applying a polyphasic approach combining 1) microbial enumeration with culture media, 2) randomly amplified polymorphic DNA (RAPD) fingerprinting of microbial communities, 3) sequencing of partial 16S ribosomal DNA (rDNA) genes, and 4) physiological tests. Viable cell counts on different culture media showed that the cocci community prevailed during the 18 h of curd fermentation and the 6 d of cheese ripening. RAPD fingerprinting made it possible to isolate 25 different strains identified by 16S rDNA sequencing as belonging to five species of Lactobacillus, three species of Streptococcus, one species of Weissella, and one species of Enterococcus. The physiological analyses of all lactic acid bacteria strains revealed that the isolates belonging to Streptococcus genus were the most acidifying, whereas lactobacilli were most proteolytic. Streptococcus thermophilus C48W and Lactobacillus delbrueckii subsp. bulgaricus B15Z dominated all through the fermentation process. Furthermore, they seemed to be stable in a subsequent whey sample analyzed after 7 mo. The recovery of strains endowed with interesting technological features, such as acidifying and proteolytic activities, and surviving in natural whey could allow the upscaling of cheese processing safeguarding the organoleptic characteristics of Scamorza Altamurana and could possibly improve other fermented dairy products.

Phenotypic and molecular identification and clustering of lactic acid bacteria and yeasts from wheat (species Triticum durum and Triticum aestivum) sourdoughs of Southern Italy.

The microflora of 25 wheat sourdoughs from the Apulia region, Southern Italy, was characterized. The sourdoughs were mainly produced from Triticum durum wheat. The number of lactic acid bacteria and yeasts ranged from ca. log 7.5 to log 9.3 colony forming units (cfu)/g and from log 5.5 to log 8.4 cfu/g, respectively. About 38% of the 317 isolates of lactic acid bacteria were identified by conventional physiological and biochemical tests. Phenotypic identification was confirmed by 16S rDNA and 16S/23S rRNA spacer region PCR. Overall, 30% of the isolates were identified as Lactobacillus sanfranciscensis, 20% as Lb. alimentarius, 14% as Lb. brevis, 12% as Leuconostoc citreum, 7% as Lb. plantarum, 6% as Lactococcus lactis subsp. lactis, 4% as Lb. fermentum and Lb. acidophilus, 2% as Weissella confusa and 1% as Lb. delbrueckii subsp. delbrueckii. Some of these species have not been previously isolated from sourdoughs. Since bakers yeast is widely used in sourdough production, Saccharomyces cerevisiae was largely found. The phenotypical relationships within the main lactic acid bacteria identified were established by using cluster analysis. A microbial map of the 25 sourdoughs was plotted showing characteristic associations among lactic acid bacteria and differences in the lactic acid bacteria species which were mainly due to the species of wheat flour, use of bakers yeast and type of bread.

Changes in the Lactobacillus community during Ricotta forte cheese natural fermentation.

The loss of microbial biodiversity due to the increase in large-scale industrial processes led to the study of the natural microflora present in a typical little known dairy product. The community of lactobacilli was studied in order to understand the natural fermentation of Ricotta forte cheese. The combined use of RAPD analysis, 16S rDNA sequencing and physiological tests allowed 33 different strains belonging to 10 species of Lactobacillus to be characterized. RAPD analysis revealed the heterogeneity of both the Lact. kefiri and Lact. paracasei species. The sequence analysis of the large 16S/23S rRNA spacer region enabled Lact. plantarum to be distinguished from Lact. paraplantarum, two closely related species belonging to the Lact. plantarum group. The recovery of strains endowed with interesting physiological characteristics, such as strong stress resistance, could improve technological and/or organoleptic characteristics of Ricotta forte cheese and other fermented foods.

Molecular and physiological characterization of dominant bacterial populations in traditional mozzarella cheese processing

The development of the dominant bacterial populations during traditional Mozzarella cheese production was investigated using physiological analyses and molecular techniques for strain typing and taxonomic identification. Analysis of RAPD fingerprints revealed that the dominant bacterial community was composed of 25 different biotypes, and the sequence analysis of 16S rDNA demonstrated that the isolated strains belonged to Leuconostoc mesenteroides subsp. mesenteroides, Leuc. lactis, Streptococcus thermophilus, Strep. bovis, Strep. uberis, Lactococcus lactis subsp. lactis, L. garviae, Carnobacterium divergens, C. piscicola, Aerococcus viridans, Staphylococcus carnosus, Staph. epidermidis, Enterococcus faecalis, Ent. sulphureus and Enterococcus spp. The bacterial populations were characterized for their physiological properties. Two strains, belonging to Strep. thermophilus and L. lactis subsp. lactis, were the most acidifying; theL. lactis subsp. lactis strain was also proteolytic and eight strains were positive to citrate fermentation. Moreover, the molecular techniques allowed the identification of potential pathogens in a non-ripened cheese produced from raw milk.

Molecular characterization of the Lactobacillus community in traditional processing of Mozzarella cheese.

The natural Lactobacillus community involved in traditional Mozzarella cheese production has been investigated. The bacterial associations of whey, curd before stretching and Mozzarella were analyzed using randomly amplified polymorphic DNA (RAPD) to follow growth kinetics, and 16S rDNA sequencing to identify the taxonomical position of isolated strains. Analysis of RAPD fingerprints revealed that the Lactobacillus community was composed of 13 different biotypes and the sequence analysis of 16S rDNA demonstrated that the isolated strains belong to L. plantarum, L. fermentum, L. helveticus and L. casei subsp. casei. In addition, two strains of Weissella hellenica were isolated on selective media for lactobacilli. The four L. casei subsp. casei strains and W. hellenica contained sequences related to the prtP gene coding for proteinase, and the highest proteolytic activity in milk was found in one strain of L. casei subsp.casei.

Opposing regulation of tau protein levels by ionotropic and metabotropic glutamate receptors in human NT2 neurons.

Human NT2-N neurons derived from retinoic acid treatment of the NTera 2 cell line were used to determine the consequences of ionotropic glutamate receptor (iGluR) hyperstimulation and possible modulatory role(s) exerted by metabotropic glutamate receptor (mGluR) activation. We found that NT2-N neurons express the NR1 subunit of N-methyl-D-aspartate (NMDA) iGluRs and mRNA encoding the 1a isoform of mGluRs. A 15 min pulse with 100 microM NMDA induced an increase in the levels of tau proteins in NT2-N cells. This effect was prevented by incubating NT2-N neurons in the presence of the mGluR agonist (1 S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD). This phenomenon was related, in terms of doses and time, with the observed 1S,3R-ACPD-mediated protection against NMDA-induced NT2-N cell death. Our findings suggest that iGluRs and mGluRs might participate in the control of human neuron viability by differentially affecting the expression of tau proteins.

[CT x-ray in recurrences of lumbar disk herniation. Usefulness of the examination with contrast enhancement]. / La TC nelle recidive di ernia discale lombare. Utilità dell'esame con contrast enhancement.

The CT is an important and valuable instrument in the study of the postoperative lumbar spine, in the patients which presented persistent clinical manifestation. In this report the technique with contrast enhancement is outlined, the criteria for its interpretations are presented, and its advantages and limitations are reviewed; pitfalls in technique interpretation are stressed. Two hundred and fifty patients are referred to the CT without and with i.v. contrast medium for this diagnostic request: scar or herniation at surgery level.