Internal transcribed spacer as a target to assess yeast biodiversity in Italian Taleggio PDO cheese

Abstract: Three batches of soft smear‐ripened Taleggio PDO cheese were made in Northern Italy during the summertime 2010. A total of 129 isolates cultured from cheese surface were examined by using PCR‐based methods and sequencing of both the ITS1 region and D1 and D2 domains of the 26S rRNA gene. Sequence analysis of isolates brought to the identification of 6 species: Debaryomyces hansenii, Kluyveromyces lactis, Kluyveromyces marxianus, Yarrowia lipolytica, Pichia guilliermondii, and Torulaspora delbrueckii. Analysis of DNA directly extracted from 45 cheese surfaces permitted to detect 2 additional species Candida sake and Candida etchellsii. D. hansenii was predominant and widespread whereas the other yeast species were detected less frequently. To determine the relationships between yeast community and the environment, 39 isolates from wooden boxes used for dry salting of cheese were analyzed as well. Sequencing of ITS1 region allowed to identify D. hansenii, T. delbrueckii, and K. lactis. ITS1 multiple sequence alignments of D. hansenii detected in wooden boxes showed an in‐del polymorphism at position 169. ITS1 secondary structures of yeasts were modeled to explore new applications of this region for molecular identification purposes. Practical Application: This study used molecular analysis to identify adventitious yeast population present in the surface of Taleggio smear‐ripened cheese. D. hansenii was found predominant in pasteurized milk, in dry salting equipment, and in all cheese samples until the end of ripening.     

Role of surface-inoculated Debaryomyces hansenii and Yarrowia lipolytica strains in dried fermented sausage manufacture. Part 1: Evaluation of their effects on microbial evolution, lipolytic and proteolytic patterns

The aim of this work was to study the effects of Debaryomyces hansenii and Yarrowia lipolytica strains, used with lactic acid starter cultures (Lactobacillus plantarum), on the manufacture of dried fermented sausages to understand their role on sausage microbial evolution, lipolytic and proteolytic patterns. The inoculation of the yeast strains did not markedly affect the sausage’s microbial flora. The sausages with the yeast strains showed more marked and earlier water activity (a_w) reductions. Moreover, the surface inoculation of the yeast strains resulted, at the end of ripening, in more pronounced proteolysis and lipolysis. The lipolytic patterns of the products were affected not only by the yeast strain but also by the level of mincing of the meat mixture used.     

New insights into the thermal desorption of the 2LiNH2 + KBH4 + LiH mixture

In situ two-dimensional synchrotron X-ray powder diffraction investigation combined with Rietveld method data analysis were performed in order to yield a complete and quantitative phases structure evolution of the polycrystalline mixture 2LiNH₂ + KBH₄ + LiH during H₂ desorption. While a first-principles, purely thermodynamics approach of the system predicted a single dehydrogenation step reaction at relatively low temperatures, it is assessed experimentally that the reaction occurs in two steps with first the formation of Li₂NH at ca. 230 °C due to the reaction between LiNH₂ and LiH plus hydrogen and ammonia evolution, followed by an additional reaction of the resulting phases with KBH₄ at 360 °C, which releases hydrogen and leads to the formation of the monoclinic and tetragonal Li₃BN₂ polymorphs. Besides pointing out possible limits of a purely thermodynamics approach inevitably relying exact knowledge of experimental quantities, it is concluded that before assuming it viable for on-board vehicle use, additional stoichiometries may be worth of investigation in order to assess any existence of lower hydrogen desorption temperature of such system.     

Thyroid Hormones and Antioxidant Systems: Focus on Oxidative Stress in Cardiovascular and Pulmonary Diseases

In previous works we demonstrated an inverse correlation between plasma Coenzyme Q₁₀ (CoQ₁₀) and thyroid hormones; in fact, CoQ₁₀ levels in hyperthyroid patients were found among the lowest detected in human diseases. On the contrary, CoQ₁₀ is elevated in hypothyroid subjects, also in subclinical conditions, suggesting the usefulness of this index in assessing metabolic status in thyroid disorders. A Low-T3 syndrome is a condition observed in several chronic diseases: it is considered an adaptation mechanism, where there is a reduction in pro-hormone T4 conversion. Low T3-Syndrome is not usually considered to be corrected with replacement therapy. We review the role of thyroid hormones in regulation of antioxidant systems, also presenting data on total antioxidant capacity and Coenzyme Q₁₀. Published studies suggest that oxidative stress could be involved in the clinical course of different heart diseases; our data could support the rationale of replacement therapy in low-T3 conditions.     

Why Our Patients Like Daily Hemodialysis

The option of daily hemodialysis (HD) was discussed in November 1998 with a group of 35 HD patients on home or self‐care/limited‐care HD in a single, freestanding unit. After the meeting, 3 patients on home HD chose to switch to daily HD. The clinical success of the first patient and the immediate followers was one of the main reasons for further extension of this experience. At the time of this writing (February 2000), 10 patients were on a daily HD program (8 at home and 2 in a self‐care/limited‐care center) and one was in training for home daily HD. One further patient who tried 1 month of daily HD dropped out for logistic reasons. On daily HD, patients are dialyzed 2 – 3 hours/day, 6 days/ week, with blood flow of 270 – 300 mL/min, on bicarbonate dialysate with individually determined levels of Na and K. The schedule is flexible and a switch to 3 – 4 dialyses/week is occasionally allowed for working needs or for vacation. In addition to the well‐known clinical advantages (better well‐being, blood pressure control, nutrition, etc.), some patients preferred daily HD because of easier organization of daily activities, including work schedule. Patients initially feared frequent needle punctures and excessive burden on partners, but those concerns proved to be less a problem than anticipated. All current patients are willing to continue daily HD; only a nursing shortage limits further extension of the program in the self‐care/limited‐care center.     

Hypercholesterolemia in Cancer and in Anorexia Nervosa: A Hypothesis for a Crosstalk

The relationship between cholesterol and cancer has been widely demonstrated. Clinical studies have shown changes in blood cholesterol levels in cancer patients. In parallel, basic research studies have shown that cholesterol is involved in the mechanisms of onset and progression of the disease. On the other hand, anorexic patients have high cholesterol levels and a high susceptibility to cancer. In this review, we first present a brief background on the relations among nutrition, eating disorders and cancer. Using several notable examples, we then illustrate the changes in cholesterol in cancer and in anorexia nervosa, providing evidence for their important relationship. Finally, we show a new possible link between cholesterol disorder in cancer and in anorexia nervosa.     

Limited Accuracy of Pan-Trk Immunohistochemistry Screening for NTRK Rearrangements in Follicular-Derived Thyroid Carcinoma

Patients with advanced thyroid cancer harboring NTRK rearrangements can be treated with highly effective selective inhibitors. Immunohistochemistry (IHC) analysis, to detect Trk protein expression, represents an appealing screening strategy for NTRK rearrangements, but its efficacy has been poorly explored in thyroid cancer. The aim of this study is to investigate the diagnostic utility of Trk IHC in the identification of NTRK rearrangements. A series of 26 follicular-derived thyroid tumors, positive for NTRK rearrangements, and 28 NTRK fusion-negative controls were retrospectively analyzed by IHC using the pan-Trk monoclonal antibody (clone {"type":"entrez-protein","attrs":{"text":"EPR17341","term_id":"523383444","term_text":"EPR17341"}}EPR17341) on the Ventana system. Area under the curve (AUC), sensitivity and specificity were calculated by ROC analysis. Trk expression was detected in 25 samples, including 22 out of the 26 NTRK-rearranged (84.6%) and three out of 28 NTRK-negative samples (10.7%). Four out of twenty-six NTRK-rearranged thyroid tumors were negative for Trk expression (15.4%), all carrying the ETV6/NTRK3 fusion. The AUC, sensitivity and specificity were 0.87, 0.85 and 0.89, respectively. A screening based on IHC analysis showed limited sensitivity and specificity in the identification of NTRK-rearranged tumors. Since falsely negative results could preclude the administration of effective targeted drugs, alternative detection strategies should be considered for thyroid cancer.     

Effect of Formulation on Physicochemical Properties and Water Status of Nutritionally Enriched Fresh Pasta

A standard fresh pasta formulation (STD, the control sample) was modified by introducing soy and carrot ingredients both in dry and in liquid forms (soy and carrot flour and soy milk and carrot juice) to obtain eight nutritionally enriched fresh pasta samples with different formulations. The effect of formulation on selected physicochemical properties and water status of fresh pasta were studied. Colour, texture (force at rupture and extensibility), and cooking loss were found significantly affected by the formulation. Soy and carrot decreased the force at rupture and extensibility of fresh pasta and increased the solids loss during cooking. Improper gluten network development due to either a steric hindrance of soy and carrot solids or improper water availability for gluten hydration due to different water–solid interaction developed were hypothesized. Soy and carrot ingredients significantly altered the water dynamics in the pasta matrix at different space-time levels (macroscopic, moisture content and water activity; macromolecular, frozen water content; molecular, proton nuclear magnetic resonance relaxometry) of fresh pasta in a manner dependent upon the physical state of the added ingredient. Soy flour increased both the frozen water content and the overall proton mobility (¹H FID, ¹H T ₁ and T ₂) of fresh pasta while these parameters did not markedly differed from STD when soy milk was used. The presence of both carrot flour and carrot juice decreased significantly the frozen water content of fresh pasta but, at a molecular level, carrot flour altered the proton molecular mobility, while carrot juice did not.     

Validation of a 1-Day Analytical Diagnostic Real-Time PCR for the Detection of Salmonella in Different Food Meat Categories

Foodborne disease caused by Salmonella represents a worldwide public health problem. In Europe, salmonellosis is still the second most commonly recorded zoonosis. Since the standard culture method for detecting Salmonella (ISO 6579:2002) requires up to 5 days to produce results, the need to develop rapid methods represents an important issue for the authorities and the producers. The aim of the present study was the in-house validation, according to ISO 16140, of an open-formula diagnostic real-time PCR for the detection of Salmonella in all the different meat categories reported in the EU Regulations relative to microbiological criteria for food safety. The assay employed specific primers and a probe target within the ttrRSBCA locus, which allows the tetrathionate respiration in Salmonella. Selectivity, relative accuracy, relative sensitivity and relative specificity were established by testing 110 bacterial strains and 175 various edible meat samples. Results showed 100 % selectivity, 100 % relative accuracy, 100 % relative sensitivity and 100 % relative specificity of the real-time PCR when compared to the standard culture method used as reference. In addition, in order to minimize the effect of the competitive micro-flora naturally present on meat samples, a highly nutritious and selective commercial medium (ONE Broth Salmonella, Oxoid) was evaluated in comparison with the classical non-selective pre-enrichment broth (buffered peptone water). Results demonstrated that the ONE Broth Salmonella medium increases the growth of Salmonella in the presence of competitive micro-flora.     

Mechanisms of the FMR1 Repeat Instability: How Does the CGG Sequence Expand?

A dynamic mutation in exon 1 of the FMR1 gene causes Fragile X-related Disorders (FXDs), due to the expansion of an unstable CGG repeat sequence. Based on the CGG sequence size, two types of FMR1 alleles are possible: “premutation” (PM, with 56-200 CGGs) and “full mutation” (FM, with >200 triplets). Premutated females are at risk of transmitting a FM allele that, when methylated, epigenetically silences FMR1 and causes Fragile X syndrome (FXS), a very common form of inherited intellectual disability (ID). Expansions events of the CGG sequence are predominant over contractions and are responsible for meiotic and mitotic instability. The CGG repeat usually includes one or more AGG interspersed triplets that influence allele stability and the risk of transmitting FM to children through maternal meiosis. A unique mechanism responsible for repeat instability has not been identified, but several processes are under investigations using cellular and animal models. The formation of unusual secondary DNA structures at the expanded repeats are likely to occur and contribute to the CGG expansion. This review will focus on the current knowledge about CGG repeat instability addressing the CGG sequence expands.