Dynamic co-culture metabolic models reveal the fermentation dynamics, metabolic capacities and interplays of cheese starter cultures.

In this study, we have investigated the cheese starter culture as a microbial community through a question: can the metabolic behaviour of a co-culture be explained by the characterized individual organism that constituted the co-culture? To address this question, the dairy-origin lactic acid bacteria Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis, Streptococcus thermophilus and Leuconostoc mesenteroides, commonly used in cheese starter cultures, were grown in pure and four different co-cultures. We used a dynamic metabolic modelling approach based on the integration of the genome-scale metabolic networks of the involved organisms to simulate the co-cultures. The strain-specific kinetic parameters of dynamic models were estimated using the pure culture experiments and they were subsequently applied to co-culture models. Biomass, carbon source, lactic acid and most of the amino acid concentration profiles simulated by the co-culture models fit closely to the experimental results and the co-culture models explained the mechanisms behind the dynamic microbial abundance. We then applied the co-culture models to estimate further information on the co-cultures that could not be obtained by the experimental method used. This includes estimation of the profile of various metabolites in the co-culture medium such as flavour compounds produced and the individual organism level metabolic exchange flux profiles, which revealed the potential metabolic interactions between organisms in the co-cultures.

Fecal Elastase Levels Predict Honeycombing in Pancreas Detected with Endoscopic Ultrasound.

Background and Study Aims: We aimed to demonstrate the association between fecal elastase levels and Rosemont categories in patients with chronic changes in pancreas detected with endoscopic ultrasound. Patients and Methods: Patients were selected consecutively from endosonography examinations performed for upper gastrointestinal subepithelial lesions and for pancreas evaluation. Pancreas imaging findings were categorized according to the Rosemont criteria using echoendoscope. Patients who were indeterminate of, suggestive of, and consistent with chronic pancreatitis were included in the study. Fecal elastase measurements were performed after the patients were qualified to participate in the study according to endosonography findings. Results: Seventy patients were included in the study. 54 of them were male. Mean age of the patients was 51.7 ± 10.2 year. There were 36 patients in the indetermine group for chronic pancreatitis. Mean fecal elastase level was 507.1 ± 14.6 µg/g in the indeterminate group. There were 24 patients in the suggestive group of chronic pancreatitis. Mean fecal elastase level was 400.4 ± 121.4 µg/g in the suggestive group of chronic pancreatitis. There were 10 patients, in the consistent group with chronic pancreatitis. Mean fecal elastase level was 134.8 ± 86.1. The difference between the three groups of fecal elastase values was statistically significant compared with Kruskal Wallis test. Ordinal logistic regression analysis showed that there was a significant relation between endosonografic categories and fecal elastase values with Nagelkerke value of 0.704. Conclusions: Fecal elastase levels of each of the endosonographic categories were significantly different from each other. Also, fecal elastase values can predict chronic changes in pancreas detected with endoscopic ultrasound.

The relationship between levels of plasma-soluble urokinase plasminogen activator receptor (suPAR) and presence of migraine attack and aura.

Migraine is one of the most common types of pain associated with sterile inflammatory conditions. Soluble urokinase plasminogen activator receptor (suPAR) is a potential novel inflammatory marker. We aim to determine the association between serum values of suPAR, procalcitonin, fibrinogen, and high-sensitivity C-reactive protein (hs-CRP) and migraine disease characteristics. The study involved a total of 60 migraine patients (33 patients in the interictal period, 27 patients in the attack period) and 30 healthy individuals. The serum values of suPAR were found to be significantly higher in migraine patients in the attack period than in migraine patients in the interictal period, and in healthy individuals (p < .01 for both). In addition, levels of suPAR were determined to be higher in migraine with aura patients than in migraine without aura patients. When we subdivided migraine patients according to frequency of attack (attacks/month), significant differences were found between the suPAR and procalcitonin levels (measured during the attack period) of those in the frequent-attack group (4-5 or more) versus those in the less frequent attack group (less than 4). Serum levels of procalcitonin were shown to be significantly higher in migraine patients during the attack period compared with migraine patients in the interictal period and in control subjects (p = .001 for both). Significant differences were found between plasma levels of fibrinogen in migraine patients versus control subjects (p < .01). No statistically significant difference was found between levels of hs-CRP in migraine patients versus the control group. These findings may show that presenting a high level of suPAR in migraine patients with attack and aura results to predisposition to occurring on the symptoms and that high levels of suPAR, procalcitonin and fibrinogen in patients with migraine result in neurogenic inflammation during migraine headaches.

Absence of exon 17 c.2970-2872delAAT mutation in Turkish NF1 patients with mild phenotype.

INTRODUCTION: Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder characterized by café-au-lait spots, neurofibromas, skinfold freckles, Lisch nodules, bone deformities, learning disabilities, and predisposition to neoplasms. It is caused by various mutations of the NF1 gene. Recently a 3-bp in-frame deletion in exon 17, c.2970-2972 delAAT mutation, has been associated with a milder phenotype of NF1 manifesting with pigmentary skin changes only. MATERIALS AND METHODS: We therefore analyzed 35 NF1 patients without neurofibromas, learning problems, or bone lesions (19 familial, 16 sporadic, age 7-44 years) for exon 17 mutations by DNA sequencing. RESULTS: We did not find the c.2970-2972 delAAT mutation in this group but identified two base changes in exon 17 (c.2989A>G and c.2894T>A), whether these two novel mutations are related to a mild phenotype remains to be confirmed in further studies. Our results suggest the reported phenotypic associations may not be valid for all populations.

The role of arginine-nitric oxide pathway in patients with Alzheimer disease.

There is a reciprocal regulation of arginase and nitric oxide synthase in L-arginine-metabolizing pathways. There are various evidences of the role of nitric oxide in several neuropsychiatric disorders including Alzheimer's disease. However, there is no study that has investigated the role of arginase as an important part of the arginine regulatory system affecting nitric oxide synthase activity in Alzheimer's disease. This study aims to investigate arginase, manganese (a cofactor of arginase), and total nitrite levels (a metabolite of NO) and their relationship to the arginine-NO pathway in patients with Alzheimer's disease. Arginase activities, Mn, and total nitrite levels were measured in plasma from 47 patients with Alzheimer's disease and 43 healthy control subjects. Plasma arginase activities and manganese were found to be significantly lower and total nitrite level higher in patients with Alzheimer's disease compared with controls. Our results suggest that the arginine-NO pathway is involved in the pathogenesis of Alzheimer's disease.

Inverse relationship between adiponectin levels and subclinical carotid atherosclerosis in patients undergoing coronary artery bypass grafting.

The purpose of this study was to examine the relation between adiponectin levels and subclinical carotid atherosclerosis in patients undergoing coronary artery bypass grafting (CABG). Serum concentrations of adiponectin and carotid intima/media thickness (IMT) were measured in 84 consecutive patients who underwent CABG. Carotid IMT both at the common carotid artery and carotid bulb level was correlated negatively and significantly (r = -0.581 and r = -0.415, respectively, P < 0.01) with the serum concentrations of adiponectin. Linear regression modeling identified adiponectin as the strongest predictive variable for carotid IMT both at the common carotid artery and carotid bulb level (P < 0.001). Stepwise regression analyses also showed that adiponectin was the strongest independent determinant of the carotid IMT both at the common carotid artery and the carotid bulb level (F = 20.215 and F = 19.565, respectively, P < 0.001). The mean number of diseased coronary arteries, mean number of distal anastomoses, cardiopulmonary bypass time, and aortic cross-clamping time did not significantly correlate with the serum concentrations of adiponectin. The findings indicate the presence of an inverse relationship between serum concentrations of adiponectin and subclinical carotid atherosclerosis in patients undergoing CABG. In these patients, the absence of a significant correlation between severity of coronary atherosclerosis and adiponectin might suggest that adiponectin levels may predict the early stages rather than further progression of atherosclerosis.