257 research outputs found

    Značaj višeredne komjuterizovane tomografije u dijagnostici bolesti srca

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    Beverage processing optimization of enzyme hydrolyzed milk permeate

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    Valorizacija permeata kao sporednog proizvoda industrije mleka je od izuzetnog ekološkog, ekonomskog i tehnološkog značaja. Cilj doktorske disertacije je razvoj tehnološkog procesa prerade permeata, kao sporednog proizvoda dobijenog nakon ultrafiltracije mleka tokom proizvodnje feta sira i svežeg („mladog“) sira. Ispitana je mogućnost enzimske hidrolize laktoze u permeatu korišćenjem enzima β-galaktozidaze izolovanog iz Kluyveromyces lactis u koncentraciji 0,1, 0,3 i 0,5 g/100g na temperaturama 20º, 30º i 40 ºC. Praćene su promene sadržaja laktoze, D–galaktoze i D–glukoze u vremenskim intervalima tokom 60 minuta. Posebna faza istraživanja obuhvatila je matematičko modelovanje i kinetiku procesa hidrolize laktoze u permeatu pod dejstvom β –galaktozidaze i primenu hidrolizovanog permeata u proizvodnji mlečnih napitaka po odabranoj formulaciji. Predložen je tehnološki proces proizvodnje napitka na bazi hidrolizovanog permeata sa dodatkom voćnih baza. Utvrđeni su parametri kvaliteta i trajnosti napitaka tokom 60 dana skladištenja. Na temperaturi 40°C dodatkom enzima β -galaktozidaze u koncentraciji 0,1g/100g za 60 minuta postiže se 100% stepen hidrolize prisutne laktoze u permeatu. Sa većom koncentracijom enzima, 0,3 g/100g odnosno 0,5g/100g, na istoj temperaturi, isti efekat se postiže za 20 minuta. Ispitivanjem kinetike hidrolize laktoze potvrđena je kinetika prvog reda. Generalno posmatrano visoki koeficijenti determinacije pokazuju dobro poklapanje eksperimentalnih rezultata i matematičkog modela reakcije prvog reda. Vrednosti se kreću od 0,974 (temperatura 20°C) do preko 0,990 (na temperaturama 30°C i 40°C) pri koncentraciji enzima 0,1g/100g. Proizvedeni napici od hidrolizovanog permeata su delaktozirani i ne sadrže mlečnu mast. Od ukupnih šećera u svim napicima više od 50% čini glukoza: 50,16% - napitak šumsko voće, 50,42% - napitak pomorandža/šargarepa, 54,65% - napitak multivitamin, odnosno 55,13% - napitak crveno voće. Najveći sadržaj vitamina C nakon proizvodnje imao je napitak sa dodatkom voćne baze multivitamin 0,3972 mg/100g, zatim šumsko voće 0,2887 mg/100g i pomo-randža/šargarepa 0,1999 mg/100g. Najveću vrednost antioksidativne aktivnosti nakon proizvodnje pokazali su uzorci napitka sa multivitaminom i šumskim voćem. Tokom perioda skladištenja dolazi do smanjenja DPPH vrednosti. Najmanji pad je u napitku sa pomorandžom / šargarepom (smanjenje za 17%), a najveći u napitku sa šumskim voćem (za 39%). Analizirani uzorci sadrže ukupnih polifenola u intervalu od 47,84 do 120,38 mg GAE/l u zavisnosti od vrste napitka, odnosno dodatih voćnih baza. Generalno može se zaključiti da se prime-njenim tehnološkim procesom dobijaju napici stabilnog fizičko-hemijskog sastava tokom 60 dana skladištenja, visoke nutritivne i niske energetske vrednosti.Valuation of the permeate as a by-product of the dairy industry is of great ecological, economic and technological importance. The aim of the PhD thesis is the development of the technological process of refining permeate, as a by-product obtained after ultrafiltration of milk during the production of feta cheese and fresh cheese. The possibility of enzymatic hydrolysis of the lactose in the permeate using the enzyme β-galactosidase isolated from Kluyveromyces lactis in a concentration of 0.1, 0.3 and 0.5 g / 100 g at a temperature of 20°, 30° and 40° C was examined. Changes in the content of lactose, D-galactose and D-glucose at intervals of 60 minutes were monitored. A special stage of the research included mathematical modeling and kinetics of lactose hydrolysis in the permeate under the influence of β-galactosidase and application of hydrolyzed permeate in the production of dairy products under the selected formulation. A technological process of producing a beverage on the basis of hydrolyzed permeate with the addition of fruit bases was suggested. Quality and durability parameters were determined for drinks during the 60 days of storage. Addition of the enzyme β-galactosidase at a concentration of 0.1 g / 100 g for 60 minutes at a temperature of 40 ° C a 100% degree of hydrolysis of lactose is achieved, present in the permeate. With a higher concentration of enzyme, 0.3 g / 100 g or 0.5 g / 100g, at the same temperature, the same effect can be achieved in 20 minutes. By examining the kinetics of lactose hydrolysis the first order kinetics was confirmed. Generally high coefficients of determination show good correspondence between the experimental results and the mathematical model of the first order reaction. Values range from 0.974 (at a temperature of 20° C) up to over 0.990 (at temperatures 30° C and 40° C) at a an enzyme concentration of 0.1g / 100g. Beverages produced from hydrolyzed permeate are lactose-free and fat-free products. More than half of the total sugar content in all beverages consists of glucose: 50.16%-forest fruit beverage, 50.42%-beverage orange/carrot, 54.65% beverage multivitamin and 55.13% - beverage red fruit. The highest vitamin C content after production was in a beverage with the addition of fruit base multivitamin (0.3972 mg/100g), followed by forest fruit (0.2887 mg/100g) and orange/carrot (0.1999 mg/100g). Beverage samples with multivitamin and forest fruits showed the highest value of antioxidant activity after production. During the storage period there is a reduction of DPPH values. The smallest decrease was in the beverage with orange/carrot (decreased 17%), and the biggest in the beverage with forest fruit (39%). The content of polyphenols in analyzed samples ranges from 47.84 to 120.38 mg GAE/L depending on the type of beverage and added fruit base. Overall it can be concluded that the applied technological process gives beverages of stable physical and chemical content during the 60 days of storage, of high nutritional value and low energy

    Additive results for the generalized Drazin inverse in a Banach algebra

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    AbstractIn this paper we investigate additive properties of the generalized Drazin inverse in a Banach algebra. We find some new conditions under which the generalized Drazin inverse of the sum a+b could be explicitly expressed in terms of a, ad, b, bd. Also, some recent results of Castro and Koliha [New additive results for the g-Drazin inverse, Proc. Roy. Soc. Edinburgh Sect. A 134 (2004) 1085–1097] are extended

    Olanzapine effects on parvalbumin/GAD67 protein expression in the layers of the retrosplenial cortex in chronically socially isolated rats

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    The alterations of gamma-aminobutyric acid (GABA) neurotransmission induced by psychosocial stress are implicated in the pathophysiology of major depressive disorder and anxiety. Olanzapine (Olz), an atypical antipsychotic, is used to treat psychiatric disorders. Since GABAergic signaling has been proposed as a potential therapeutic target for antipsychotics, we aimed to determine the susceptibility of different layers (1;2/3/4;5/6) in the retrosplenial cortex (RSC), including both granular c (RSGc) and dysgranular (RSD) subregions, in adult male rats exposed to chronic social isolation (CSIS) (six weeks), an animal model of depression, and/or treatment with Olz (7.5 mg/kg/day) (lasting 3 weeks of six-week CSIS), on the protein expression of parvalbumin interneurons, the largest class of GABAergic inhibitory neurons, and glutamate decarboxylase 67 (GAD67), as the main GABA-synthesizing enzyme. Results showed that CSIS decreased the number of GAD67 positive (GAD67+) cells in 5/6 layers of RSGc and increased in 1 and 2/3/4 layers of RSD, with no significant effect on PV positive (PV+) cells. Treatment with Olz in CSIS rats increased the number of GAD67+ cells in the 5/6 layers of the RSC and decreased in 1 and 2/3/4 layers of the RSD. Regarding PV+ cells, Olz treatment led to a decrease in 2/3/4 layers of RSD with no significant effect in RSGc. Overall, this study provided an insight into the neuroinhibitory transmission in the RSC, at the level of subregions and layers following CSIS and/or Olz treatment, and its involvement in the rat model of depression.Poster Session: Bran Stimulation & Signalling, Phase Separation and Open Dat

    Phenolic Composition, Antioxidant, Anti-Enzymatic, Antimicrobial and Prebiotic Properties of Prunus spinosa L. Fruits

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    Blackthorn (Prunus spinosa L.) fruit is bluish-black wild fruit traditionally used in nutrition and medicine. It is recently gaining attention as a functional food and an underutilized source of bioactive compounds for application in the food and pharmaceutical industry. This study aimed to assess the health-promoting potential of blackthorn fruits from Serbia by examining their chemical composition and in vitro biological activities. Phytochemical analysis of the blackthorn fruit extracts was performed using LC-DAD-ESI-MS. The total phenolic (TPC), total flavonoid (TFC), total anthocyanin (TAC) content, antioxidant capacity, and enzyme inhibitory activities were determined spectrophotometrically. The antimicrobial and prebiotic properties were tested using the broth microdilution method. Twenty-seven phenolics belonging to the classes of hydroxybenzoic and hydroxycinnamic acids derivatives, flavonoids, and anthocyanins were identified, with caffeoylquinic acid as the most abundant compound. Blackthorn extracts were characterized by notable TPCs, TFCs, and TACs, and free radical scavenging and reducing ability. The enzyme inhibitory effects (IC50 = 0.43–2.16 mg/mL) were observed towards α-amylase, α-glucosidase, acetylcholinesterase, and tyrosinase. Blackthorn fruit extracts in a concentration-dependent manner (0.3–5 mg/mL) stimulated the growth of several probiotic microorganisms and their mixtures, especially the yeast Saccharomyces boulardii. Obtained results support further evaluation of the functional food potential of blackthorn fruit

    SECONDARY ADRENAL INSUFFICIENCY MIMICKING ABDOMINAL CAUSE OF RECURRENT ABDOMINAL PAIN IN A PREPUBERTAL GIRL

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    Recurrent abdominal pain (RAP) in children is defined as at least three episodes of pain that occur over at least three months and affect the child's ability to perform normal activities. The prevalence of recurrent abdominal pain in a population of schoolchildren varies from 10% to even 45%. Pituitary disorders are rarely considered as causative factor in children with abdominal pain, especially in absence of midline facial defects and in case of emergency, when growth monitoring is neglected or not performed carefully. Herein we report an unusual case of RAP caused by secondary adrenal insufficiency. An 8-year-old girl was hospitalized repeatedly because of RAP. Biological parameters including white blood cell count, hemoglobin value, C-reactive protein, glucose, electrolytes were within the normal range. Low cortisol combined with low ACTH values was the clue for diagnosis. The magnetic resonance imaging (MRI) of the pituitary region revealed anterior pituitary hypoplasia and pituitary stalk interruption. To the best of our knowledge, this is the first report of child with RAP caused by pituitary disorder. Possible inherited, autoimmune and post-traumatic causative factors are discussed

    Putative Role of Neutrophil Extracellular Trap Formation in Chronic Myeloproliferative Neoplasms

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    Myeloproliferative neoplasms (MPNs) are hematologic malignancies characterized by gene mutations that promote myeloproliferation and resistance to apoptosis via constitutively active signaling pathways, with Janus kinase 2-signal transducers and the activators of transcription (JAK-STAT) axis as a core part. Chronic inflammation has been described as a pivot for the development and advancement of MPNs from early stage cancer to pronounced bone marrow fibrosis, but there are still unresolved questions regarding this issue. The MPN neutrophils are characterized by upregulation of JAK target genes, they are in a state of activation and with deregulated apoptotic machinery. Deregulated neutrophil apoptotic cell death supports inflammation and steers them towards secondary necrosis or neutrophil extracellular trap (NET) formation, a trigger of inflammation both ways. NETs in proinflammatory bone marrow microenvironment induce hematopoietic precursor proliferation, which has an impact on hematopoietic disorders. In MPNs, neutrophils are primed for NET formation, and even though it seems obvious for NETs to intervene in the disease progression by supporting inflammation, no reliable data are available. We discuss in this review the potential pathophysiological relevance of NET formation in MPNs, with the intention of contributing to a better understanding of how neutrophils and neutrophil clonality can orchestrate the evolution of a pathological microenvironment in MPNs

    Podklasa teških lanaca i nivo ekspresije sijalinske kiseline na njima određuju hromatografsku raspodelu humanih monoklonskih imunoglobulina G

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    Anion exchange chromatography is a widely accepted method for purification of immunoglobulins. In this work, we used human monoclonal immunoglobulin G (IgG) with structure and solubility of normal human IgG as a model for studying chromatographic behavior of particular molecular forms of IgG. Human sera with monoclonal IgG were fractionated on a strong anion exchanger, Q Sepharose Fast Flow. With 20 mM Tris pH 7.5 as a start buffer, 42% of human monoclonal IgG passed through column, and 58% of them remained adsorbed. Bound monoclonal IgG were eluted from the exchanger by linear increasing of concentration of NaCl from 0 to 0.5 M. The chromatographic distribution of human monoclonal IgG correlated with their electrophoretic mobilities in agarose gels, and it was dependent on ã heavy chain isotype. Light chain type, as well as serum concentration of monoclonal IgG did not influence their chromatographic behavior. The level of heavy chain sialic acid expression, but not of galactose and N-acetylglucosamine, significantly determined chromatographic distribution of serum monoclonal IgG. In addition to the information on the chromatographic behavior of human monoclonal IgG, we believe that the presented data could provide useful information about the possible use of Q Sepharose Fast Flow matrix for the isolation of specific molecular forms of human IgG.Zbog velike molekulske heterogenosti humanih imunoglobulina G (IgG) (4 izotipa, 20 alotipova i preko 600 mogućih glikoformi) ne postoji jedinstven protokol za izolovanje svih molekulskih formi IgG. Jonoizmenjivačka hromatografija je široko prihvaćen metod za izolovanje i prečišćavanje humanih IgG, pre svega zbog činjenice da se separacija odvija u blagim uslovima, što pored efikasnog prečišćavanja omogućava da struktura i funkcija IgG kao antitela ostane očuvana. Za izolovanje humanih IgG mogu se koristiti i slabi i jaki anjonski izmenjivači. Međutim, koji će od brojnih matriksa koji danas postoje na tržištu biti odgovarajući za izolovanje specifičnih molekulskih formi humanih IgG, može se znati samo nakon testiranja. U ovom radu, humani monoklonski IgG iz seruma bolesnika sa monoklonskim gamapatijama su izolovani preparativnom hromatografijom na Q Sepharose Fast Flow anjonskom izmenjivačkom matriksu. Kada je kao startni pufer korišćen 20 mM Tris-HCl, pH 7,5, 42% analiziranih monoklonskih IgG nije se vezivalo za matriks i bilo je moguće izolovati ih u čistoj formi. Preostalih 58% monoklonskih IgG, različitim intenzitetom vezivali su se za matriks, i sa njega su eluirani 0,09-0,43 M Tris, pH 7,5/NaCl. Hromatografska raspodela monoklonskih IgG je bila u korelaciji sa njihovom elektroforetskom pokretljivosti u gelu agaroze i podklasom γ teškog lanca, a nije bila određena tipom lakog lanca i serumskom koncen- tracijom monoklonskog IgG. Nivo ekspresije sijalinske kiseline na teškim lancima je značajno uticao na hromatografsku raspodelu humanih monoklonskih IgG, dok je nivo ekspresije druga dva terminalna šećera, galaktoze i N-acetilglukozamina, bio bez uticaja. Smatramo da prikazani rezultati mogu biti od koristiti u kreiranju protokola za izolovanje humanih monoklonskih IgG jer pored toga što daju informacije o njihovom hromatografskom ponašanju daju i informaciju o mogućnosti korišćenja Q Sepharose Fast Flow anjonskog matriksa za izolovanje pojedinih molekulskih formi humanih IgG

    Kompleksna modulacija sila tokom preciznog hvata šake primenom ponavljane transkranijalne magnetne stimulacije pražnjenjima u teta frekvenciji iznad dorzalnog premotornog korteksa

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    Background/Aim. Adaptive control and fingertip force synchronization of precise grasp stability during unimanual manipulation of small objects represents an illustrative example of highly fractionated movements that are foundation of fine motor control. It is assumed that this process is controlled by several motor areas of the frontal lobe, particularly applicable to the primary motor (M-1) and dorsal premotor cortex (PMd). Aiming to examine the role of PMd during fine coordination of fingertip forces we applied theta burst repetitive magnetic stimulation (TBS) to disrupt neural processing in that cortical area. Methods. Using a single-blind, randomized, crossover design, 10 healthy subjects (29 ± 3.9 years) received single sessions of continuous TBS (cTBS600), intermittent TBS (iTBS600), or sham stimulation, separate from one another at least one week, over the PMd region of dominant hemisphere. Precision grasp and lift were assessed by instrumented device, recording grip (G) and load (L) forces, during three manipulation tasks (ramp-and-hold, oscillation force producing and simple lifting tasks), with each hand separately, before and after interventions. Results. We observed the improvement of task performance related to constant error (CE) in oscillation task with the dominant hand (DH) after the iTBS (p = 0.009). On the contrary, the cTBS reduced variable error (VE) for non-dominant hand (NH), p = 0.005. Considering force coordination we found that iTBS worsened variables for NH (G/L ratio, p = 0.017; cross-correlation of the G and L, p = 0.047; Gain, p = 0.047). Conclusion. These results demonstrate the ability of TBS to modulate fingertip forces during precision grasping and lifting, when applied over PMd. These findings support the role of PMd in human motor control and forces generation required to hold small objects stable in our hands.Uvod/Cilj. Adaptivna kontrola i sinhronizacija sila prstiju šake tokom preciznog hvata pri manipulisanju malim predmetima jednom rukom predstavlja ilustrativni primer visoko frakcionisanih pokreta koji predstavljaju temelj motorne kontrole preciznih pokreta. Pretpostavlja se da ovim procesom upravlja nekoliko motornih oblasti frontalnog režnja, i to prvenstveno primarni motorni (M-1) i dorzalni premotorni korteks (PMd). Cilj istraživanja bio je ispitivanje uloge PMd-a tokom vršenja pokreta koji zahtevaju finu koordinaciju sila prstiju šake. U istraživanju smo primenili ponavljanu magnetnu stimulaciju pražnjenjima u teta frekvenciji, kako bi ometali neuralno procesiranje u toj oblasti moždane kore. Metode. Primenom jednostrano slepe studije, uz nasumičnu raspodelu i ukršteni dizajn, 10 zdravih ispitanika (29 ± 3,9 godina) bilo je izloženo pojedinačnim sesijama kontinuirane magnetne stimulacije (cTBS600), ili intermitentne ponavljane magnetne stimulacije (iTBS600), pražnjenjima u teta frekvenciji kao i prividnoj stimulaciji iznad PMd regiona dominantne hemisfere, odvojenih međusobno, najkraće nedelju dana. Precizanost hvata šake i podizanja procenjivani su uređajem koji je registrovao silu stiska (G) i silu podizanja (L) prilikom izvođenja tri zadatka (zadatak sa zadatim profilom L, zadatak sa oscilatornim variranjem nivoa L i zadatak sa podizanjem), koji su izvođeni sa obe ruke odvojeno, i to pre i nakon svake intervencije. Rezultati. Nakon primene iTBS protokola zabeleženo je poboljšanje izvođenja iskazano konstantnom greškom (CE) u zadatku sa oscilatornim variranjem nivoa L, kada je izvođen dominantnom rukom (DH), p = 0.009. Suprotno tome, primena cTBS protokola dovela je do smanjenja promenjive greške (VE) za nedominantnu ruku (NH), p = 0.005. Sa aspekta koordinacije sila utvrđeno je da je iTBS protokol doveo do pogoršanja rezultata praćenih pokazatelja za nedominantnu ruku (G/L odnos, p = 0.017; korelacija G i L, p = 0.047; prirast sile p = 0.047). Zaključak. Rezultati našeg istraživanja ukazuju na mogućnost modulacije sila prstiju šake tokom preciznog hvata i podizanja, ukoliko se TBS primeni iznad PMd-a. Dobijeni nalazi podržavaju ulogu PMd u motornoj kontroli i generisanju sila neophodnih za stabilno držanje malih predmeta kod ljudi
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