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Abstract

A highly sensitive high-performance liquid chromatography (HPLC) method was developed for the simultaneous determination of eight biogenic amines in aquatic products. The biogenic amines in the sample were extracted with 5% trichloroacetic acid, derived with dansyl chloride (Dns-Cl) and quantified by a UV detector. The results showed that tryptamine (TRY), 2-phenethylamine (PHE), putrescine (PUT), cadaverine (CAD), histamine (HIS), tyramine (TPY), spermidine (SPD), and spermine (SPM) were effectively separated in 18 min in the range of 0.1–50 mg/kg with a good linear coefficient (r 2 > 0.999). The detection limits (LODs) of the eight biogenic amines were 0.007–0.021 mg/kg while the limits of quantification (LOQs) were 0.024–0.069 mg/kg with the recoveries basically between 68 and 123%. The determination of eight biogenic amines in five commercial fermented aquatic products indicating that the developed method could be applied for the simultaneous detection of biogenic amines in multiple aquatic products.

Open access
Progress in Agricultural Engineering Sciences
Authors: Judit Perjéssy, Ferenc Hegyi, Magdolna Nagy-Gasztonyi, Rita Tömösközi-Farkas and Zsolt Zalán

Abstract

Nowadays, demand for products which beyond the overall nutritional value have a feature that protects the consumer health, have increased. Several studies have proved that fruit juices can become a suitable carrier or medium for probiotic organisms. Therefore, the aim of our study was to investigate the possibility of the probiotication of sour cherry juice (SCJ) by fermentation with probiotic starter culture. During the fermentation 9 Lactobacillus strains were used and Újfehértói fürtös sour cherry species as raw material. To reach the recommended probiotic cell count we investigated the pH adjustment, supplementation of nutrients, the effect of dilution, and strain adaptation to SCJ. In our study the properties of the strains – such as reproduction and metabolism – and its effect on the raw material were investigated. A significant difference was observed between the number of viable cells of certain Lactobacillus strains, that is important in point of view of the development of probiotic-containing products. Furthermore, the lactic acid fermented SCJ can enhance the polyphenol content and antioxidant activity to promote the health of consumers.

Open access

When are we somewhere and when are we not? When is it “here”, when is “now” and when is it not? In everyday life, this question can usually have a clear answer. But we all know the state of mind - if not from elsewhere, then from school - when we are physically present somewhere, but in fact our minds are elsewhere we are in a completely different place in spirit, being busy with something else. We can barely remember what happened in the classroom, later we are left with only what caught our attention at that time, what we were really busy with at the time. One might think that in architecture it may not even be worth addressing this issue, the situation seems so clear: here is a definite place with specific geometric features and history, shaped and formed by the mysterious “genius loci”, and now is our age, the present in which we live. According to the common opinion today, good architecture expresses its own age and its own time, catching the spirit of the place. However, it is enough to think only of the Gothic cathedrals to see the very partial validity of this view. In cathedrals, the purpose of the now and here is exactly to serve, display, illustrate the time and place of the not-now and not-here.

Összefoglaló Mikor vagyunk valahol, és mikor nem? Mikor van itt, mikor van most és mikor nem? A mindennapi életben e kérdésre általában egyértelműen válaszolunk. De mindnyájan ismerjük azt a lelkiállapotot - ha máshonnan nem, hát az iskolából -, amikor fizikailag valahol vagyunk, de valójában egészen máson jár az eszünk, lélekben egészen máshol vagyunk, mással vagyunk elfoglalva. Alig emlékszünk arra, hogy mi történt ott akkor az órán, később csak az marad meg bennünk, ami akkor figyelmünket lekötötte, ami akkor valójában foglalkoztatott. Azt gondolhatnánk, hogy az építészetben talán nem is érdemes foglalkozni ezzel a kérdéssel, olyan egyértelműnek látszik a helyzet: az itt, egy meghatározott hely sajátos geometriai tulajdonságokkal és történelemmel, amelyet a titokzatos „genius loci” alakít, formál, a most pedig a mi korunk, a jelen, amelyben élünk. Mai általánosan elterjedt vélekedésünk szerint a jó építészet a hely szellemét megérezve saját korát, saját idejét fejezi ki. Elég azonban csupán a gótikus katedráli- sokra gondolnunk ahhoz, hogy belássuk e vélekedés nagyon is részleges érvényességét. A katedrálisok- ban a most és itt célja éppenséggel a nem most és a nem itt idejének és helyének szolgálata, megjelenítése, szemléltetése.

Open access

Abstract

Bovine tuberculosis (bTB) is a common zoonosis prevalent in many countries with grave economic consequences. Most developed and developing countries have implemented the test-and-slaughter policy to protect public health and reduce economic losses in the cattle industry. The official diagnosis of bTB is based on assays dependent on cell-mediated immunity (CMI). CMI-based diagnosis demonstrates diagnostic incapability at late stages of infection, which could be overcome by diagnosis based on humoral immunity (HI). Therefore, there is an urgent need to identify and define the B cell antigenome of Mycobacterium bovis. In this study, the B cell antigenome of culture filtrate proteins (CFP) was defined by mass spectrometry-based proteomics technology. Four spots were detected on 2-dimensional gel electrophoresis (2-DE) against M. bovis-positive serum in an immunoblotting experiment. Twenty-one proteins were identified in four spots by proteomic tools, such as Mb2900, Mb2898, Mb0448, Mb3834c, Mb1918c, Mb0134c, Mb0358 and Mb1868c, which are known B cell antigens, including 13 new proteins, i.e. Mb3751, Mb2006c, Mb3276c, Mb2244, Mb1164c, Mb2553c, Mb2946c, Mb1849c, Mb1511c, Mb1034c, Mb2616c, Mb0854c and Mb2267. These new proteins identified by 2-DE and immunoblotting were the B cell antigens used in developing serological diagnostic methods based on HI to bTB.

Restricted access

Abstract

An 11-year-old Hanoverian gelding used for jumping was evaluated for gait abnormalities and hoof problems in the hindlimbs. Clinical examinations revealed signs consistent with shivers. A thyroid gland enlargement was noticed, baseline serum thyroid hormone (TH) concentrations were low, and a low response to thyrotropin-releasing hormone administration was observed. Hypothyroidism was suspected. The horse was treated with levothyroxine for 1 year. TH concentrations returned to the normal range by week 4 of treatment. Thirty weeks after the initiation of levothyroxine therapy, the gait abnormality improved. Our findings suggest that the assessment of thyroid status and especially of the subclinical thyroid gland disorders in horses affected with shivering, as well as evaluation of the effects of levothyroxine on the improvement of clinical signs could be promising in establishing the aetiopathogenesis and/or treatment of shivering in horses.

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Abstract

Aeromonads are recognised as important pathogens of fishes. In this study, ten water samples were randomly collected from pet shops' fish tanks and home aquaria inhabited by several fish species (silver arowana, koi, goldfish, catfish, pictus fish, silver shark and silver dollar fish). Altogether 298 colonies were isolated using Aeromonas selective agar. A total of 154 isolates were then confirmed as belonging to the genus Aeromonas using the GCAT gene. Using ERIC-PCR, a total of 40 duplicate isolates were excluded from the study and 114 isolates were subjected to PCR-RFLP targeting the RNA polymerase sigma factor (rpoD) gene using lab-on-chip. A total of 13 different Aeromonas species were identified. The most prevalent species were A. veronii (27%, 31/114), followed by A. dhakensis (17%, 19/114), A. finlandiensis (9%, 10/114), A. caviae (8%, 9/114), A. hydrophila (4%, 4/114), A. jandaei (4%, 4/114), A. rivuli (3%, 3/114), A. enteropelogens (2%, 2/114), A. tecta (2%, 2/114), A. allosaccharophila (1%, 1/114), A. eucrenophila (1%, 1/114), A. media (1%, 1/114) and A. diversa (1%, 1/114). Twenty-six isolates (23%) were unidentifiable at species level. The present study demonstrates that Aeromonas species are highly diverse in freshwater fish tanks, and suggests the potential risks posed by the isolated bacteria to the health of ornamental fish species.

Restricted access

Abstract

Similarly to other industries wineries also increasingly attempt to minimize and utilize waste to protect our environment. The aim of this study was to determine the optimal parameters (temperature, solvent concentration, and time) of extracting total polyphenol content (TPC) from Tokaji Aszú marc using two different extraction solvents: ethanol–water and isopropanol–water (1:4 solid/liquid ratio). The extractions were achieved based on Central Composite Design with Response Surface Method (CCRD–RSM). The optimal extraction parameters in the case of ethanol–water solvent: 60 °C temperature, 59.5% ethanol concentration in solvent, 5 h. At these parameters the probable TPC concentration is 23966.2 uM GAE/L. The optimal extraction parameters in the case of isopropanol–water solvent: 60 °C temperature, 52% ethanol concentration in solvent, 5 h. At these parameters the probable TPC concentration is 7188.44 uM GAE/L. In both cases the binary solvent was better than the mono-solvent. Ethanol–water solvent was more efficient than the isopropanol–water solvent.

Open access

Abstract

An ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC–MS/MS) method was developed to determine the fenofibric acid (FA) in human plasma and applied to a pharmacokinetic study of fenofibrate tablet (Lipanthyl® supra, 160 mg) on Chinese subjects which had not been reported. Bezafibrate was used as an internal standard (IS), and the plasma samples were precipitated by methanol. Multiple reaction monitoring (MRM) mode was used to quantitatively analyzed FA m/z 317.2 → 230.7 and the IS m/z 360.0 → 274.0 in the electrospray ionization (ESI) negative interface. The calibration curves were linear over the range of 50–30,000  ng/mL (r 2  ≥  0.996). The intra-day and inter-day precision (coefficient of variation, CV%) was less than 2.7 and 2.5%, respectively. The accuracy (relative error, RE%) ranged from −4.5 to 6.9%. The average recovery was higher than 86.2%, and the matrix effect was between 95.32 and 110.55%. The simple, rapid, and selectivity method was successfully applied to the pharmacokinetic study of fenofibrate tablets on Chinese subjects.

Open access

Abstract

Recently, the thermal performance of the parabolic trough collector (PTC), augmented to be more applicable and efficient, received intensive research. These studies aimed to improve heat transfer in the receiver part, in order to decrease the heat loss, and enhance the heat transfer to the thermal fluid. Many previous review papers focused on the numerical sides rather than the experimental side. Several research papers recommended doing more research in the experimental field; in order to decrease the gap between the numerical and experimental results, as well as increase the confidence level of what has been done in the theoretical field researches. Regarding the recommendations of the recent papers to decrease the gap between numerical and experimental aspects, this review paper focused on the recent experimental research related to thermal enhancement performance in the receiver part of the parabolic solar collector. In this research, different categories of the enhancement methods are discussed in detail through this review, namely nanofluids, surface modifications, and inserts models or the two categories combined together. We discussed these categories for different parabolic troughs considering only the recent experimental research between the period from 2014 up to 2019. Some parameters were discussed, such as the main dimensions of the examined receiver and parabolic collector. Moreover, types of nanoparticle specifications and preparation methods with different base fluids were highlighted. In addition, we discussed different aspects of using inserts models and inlet and outlet surface modification methods. Finally, the main thermal efficiency and thermal performance enhancement results for each work were presented.

Open access

Absztrakt:

Bevezetés: A COVID–19 kórlefolyásában újabban több szerző felvetette a D-dimer-pozitivitás és a D-dimer-emelkedés prediktív értékét a betegség súlyosbodásában, illetve az eseti halálozásban. Célkitűzés: Magyar betegek értékeinek összehasonlítása a nemzetközi adatokkal, ennek részeként a D-dimer prediktív értéke a 2 héten belüli eseti halálozásra. Módszerek: A szerzők 51, RT-PCR-rel igazolt SARS-CoV-2-fertőzött beteg D-dimer-eredményeit dolgozták fel retrospektív módon. Megvizsgáltuk, hogy ha a D-dimer eléri vagy meghaladja a vágóérték 4-szeresét, akkor ez milyen kockázatot (odds ratio) jelent a halálozásra. Logisztikus regresszióval meghatároztuk, hogy a 2 héten belüli halálozás esélyhányadosa a konvencionális vágóérték hányszorosa mellett lesz szignifikáns. Eredmények: Az 51 betegből 13 halt meg a kórházba kerülést követően 2 héten belül. Megállapítottuk, hogy a tradicionális, 0,5 µg/ml FEU vágóérték mellett meghatározott D-dimer-pozitivitásnak alacsony a prediktív értéke a halálozásra. Ha azt vizsgáltuk, hogy a D-dimer eléri vagy meghaladja a vágóérték 4-szeresét, és ez milyen kockázatot jelent a halálozás szempontjából, akkor a logisztikus regresszió paraméterei 1,64-szeres emelkedést mutattak (p = 0,00183), és az esélyhányados (odds ratio) értéke 5,17 (CI 95% = 1,32–20,22) volt. A D-dimer prediktív értéke a halálozásra az életkor függvényében változik. A 13 elhunyt közül 12 idősebb volt 80 évesnél, így a 80 év feletti életkor a magas D-dimer-szintnél nagyobb kockázatot jelentett a halálozásra, odds ratio: 20,7 (CI 95% = 2,41–175,5). Következtetés: A több mint négyszeres vágóértékre emelkedett D-dimer-szint az életkor mellett COVID–19-ben előre jelezheti a 2 héten belüli halálozást. Orv Hetil. 2020; 161(41): 1739–1743.

Open access