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Cobalamin and holotranscobalamin measurements in the obese
No full textPretilost se smatra jednom od najčešćih bolesti modernog društva s kompleksnom etiologijom koja se razvija zbog neuravnoteženog unosa i potrošnje energije pri čemu je dominacija na strani unosa. Pretilost uzrokuje brojne komplikacije vezane uz razne organske sustave. Vitamin B12 ključan je u eritropoezi, procesu metilacije te je kofaktor raznih enzima. 80-94% ukupnog kobalamina vezano je za haptokorin i taj dio čini neaktivnu frakciju, dok je ostatak vezan za aktivni oblik, holotranskobalamin. Deficit vitamina B12 može dovesti do hematoloških abnormalnosti te demijelinizacije središnjeg živčanog sustava, zbog čega ga je važno na vrijeme uočiti. Koncentracija kobalamina unutar referentnog intervala ne mora značiti adekvatan status vitamina B12 zbog čega on ne predstavlja dobar marker deficita vitamina B12. Holotranskobalamin kao aktivni oblik vitamina B12 predstavlja bolji izbor kao marker deficijencije. Cilj ovog istraživanja bio je ispitati postoji li statistički značajna razlika u koncentracijama kobalamina i holotranskobalamina kod pretilih ispitanika (ITM > 25 kg/m2) u usporedbi s ispitanicima normalne tjelesne mase. Istraživanje je provedeno u Kliničkom zavodu za laboratorijsku dijagnostiku KBC-a Zagreb, na 195 ispitanika od čega je 103 normalne tjelesne mase, a 92 pretilo. Koncentracije analita određene su kemiluminiscentnom imunokemijskom metodom s mikročesticama (CMIA) na analizatoru Abbott Alinity i za kobalamin, a za holotranskobalamin na analizatoru Architect. Utvrđivanje statistički značajnih razlika ispitano je Mann-Whitney testom. Rezultati su pokazali statistički značajno nižu koncentraciju kobalamina kod pretilih ispitanika u usporedbi s ispitanicima normalne tjelesne mase. Medijan izmjerenih koncentracija nije ispod preporučene cut-off vrijednosti (150 pmol/L). Iako je kod pretilih ispitanika izmjerena niža koncentracija holotranskobalamina, nije pronađena statistički značajna razlika između skupina.Obesity is considered to be one of the most prevalent diseases in modern-day society. It is an illness with complex etiology that occurs due to an imbalanced input and usage of energy where the input of energy is larger than the usage. Obesity is the cause of many complications related to different organ systems. Vitamin B12 is a key vitamin in erythropoiesis, and methylation, and it is a cofactor of different enzymes. 80-94% of total cobalamin is an inactive fraction bonded to haptocorrin while the rest is bonded in holotranscobalamin. Vitamin B12 deficiency can lead to hematological abnormalities and demyelination of the central nervous system which is why early detection is important. Cobalamin concentration within the reference range does not equate to an adequate status of vitamin B12 which is why this assay is not the best marker of vitamin B12 deficiency. As an active form of cobalamin, the holotranscoobalamin assay represents a better choice in detecting deficiency. The goal of this research was to determine whether there is a statistically significant difference in cobalamin and holotranscobalamin concentrations between a group of obese subjects (BMI > 25 kg/m2) and a group of subjects with a normal body mass index. The research was conducted at the Department of Laboratory Diagnostics at the University Hospital Centre in Zagreb on 195 subjects, of which 103 had normal body mass index, and 92 were obese. Analytes concentrations were measured using the chemiluminescent microparticle immunoassay (CMIA) on the Abbott Alinity analyzer for cobalamin, and on the Architect analyzer for holotranscobalamin. The Mann-Whitney test was used to determine whether there was a statistically significant difference in the concentrations. The results show statistically significant lower cobalamin concentration in obese subjects compared to subjects with a normal body mass index. The median of measured cobalamin concentrations was not below the recommended cut-off value (150 pmol/L). Even though holotranscobalamin concentration measured in obese subjects was lower, there was not a statistically significant difference between the two groups of subjects
The effects of Globularia alypum L. on radish (Raphanus sativus L.) seed germination and on the level of non-enzymatic antioxidants in radish seedlings grown in the presence of excess copper(II) ions
No full textCilj ovog rada bio je ispitati učinak različitih koncentracija metanolnog ekstrakta grmaste glavulje (Globularia alypum L., Plantaginaceae) na klijavost sjemenki i razinu neenzimskih antioksidansa u klijancima rotkvice (Raphanus sativus L., Brassicaceae) koji su bili izloženi oksidacijskom stresu izazvanom suviškom iona bakra(II). Sjemenke su bile predtretirane dva sata destiliranom vodom i odabranim koncentracijama ekstrakta grmaste glavulje otopljenog u destiliranoj vodi (50, 500 i 5 000 μg/mL), a nakon toga tretirane su s 3,5 mL 0,005 M CuSO4 ili destilirane vode (negativna kontrola). Nakon 5 dana klijanja na dnevnoj svjetlosti pri temperaturi 20 ± 2 °C, izračunati su parametri klijavosti (ukupna klijavost, prosječno vrijeme klijanja i prosječna brzina klijanja), izmjerena duljina korjenčića i hipokotila te izvagana masa suhih klijanaca. Nakon toga su pripremljeni homogenati klijanaca rotkvice u 5%-tnoj (w/v) trikloroctenoj kiselini. Nakon centrifugiranja i odvajanja supernatanta, određen je sadržaj ukupnih fenola i koncentracija reduciranog glutationa. Tretman 0,005 M CuSO4 statistički je značajno smanjio klijavost sjemenki, duljinu korjenčića i hipokotila te suhu masu klijanaca rotkvice u odnosu na negativnu kontrolu. Također, smanjio je i razinu neenzimskih antioksidansa u klijancima rotkvice, sadržaj ukupnih fenola i koncentraciju reduciranog glutationa. Dvije primijenjene koncentracije ekstrakta grmaste glavulje (50 i 500 μg/mL) statistički su značajno povećale klijavost sjemenki rotkvice u tretmanu s bakrom (p < 0,05). U istom tretmanu, sve su koncentracije ekstrakta statistički značajno povećale duljinu hipokotila klijanaca, dok su dvije koncentracije (500 i 5 000 μg/mL) povećale duljinu hipokotila i u usporedbi s negativnom kontrolom. Nadalje, sve su koncentracije ekstrakta povećale razinu neenzimskih antioksidansa, ali nisu imale utjecaj na duljinu korjenčića i suhu masu klijanaca. Dobiveni rezultati ukazuju na to da vrsta G. alypum može smanjiti negativne učinke oksidacijskog stresa izazvanog suviškom iona bakra(II) te potaknuti rast rotkvice.The aim of this study was to explore the effects of different concentrations of Globularia alypum L. (Plantaginaceae) methanolic extract on radish (Raphanus sativus L.) seed germination and on the level of non-enzymatic antioxidants in radish seedlings which were exposed to oxidative stress in the presence of excess copper(II) ions. Seeds were pre-treated for two hours with distilled water and chosen concentration of G. alypum extract dissolved in distilled water (50, 500 and 5000 μg/mL) and afterwards treated with 3.5 mL of 0.005 M CuSO4 or distilled water (negative control). After five days of germination in daylight at 20 ± 2 °C, germination parameters (total germination, mean germination time and mean germination rate) were assessed, the root and hypocotyl lengths measured, and the dry masses of radish seedlings weighed. Afterwards, seedling homogenates were prepared using 5% (w/v) trichloroacetic acid. After centrifugation and separation of supernatant, total phenolic content and reduced glutathione concentration were determined. Treatment with 0.005 M CuSO4 significantly decreased seed germination, the root and hypocotyl lengths, and dry mass of radish seedlings compared to negative control. It also decreased the level of non-enzymatic antioxidants in radish seedlings, total phenolic content and reduced glutathione concentration. Two applied concentrations of G. alypum extract (50 and 500 μg/mL) significantly increased germination percentages of radish seeds in the copper treatment (p < 0.05). In the same treatment, all extract concentrations significantly increased hypocotyl lengths, while two concentrations (500 and 5000 μg/mL) increased hypocotyl lengths also compared to negative control. Furthermore, all extract concentrations significantly increased the level of non-enzymatic antioxidants but had no effect on root length and seedling dry mass. Obtained results indicate that G. alypum may reduce the negative effects of oxidative stress induced by excess of copper(II) ions and promote radish growth
Pregled dostupnih skala za procjenu opterećenja aritikolinergičkim lijekovima
No full textAnticholinergic medications are frequently used by older adults.
They act on muscarinic acetylcholine receptors and antagonise
the effects of acetylcholine by competitively binding to these receptors. Usually,
they are used to manage a wide range of clinical conditions, including urinary
frequency, urgency and incontinence, irritable bowel syndrome, depression,
psychosis, chronic obstructive pulmonary disease and Parkinson's disease.
Unfortunately, simultaneously they are associated with a wide range of adverse
effects to which elderly patients are particularly sensitive. Most common adverse effects include 1dry mouth, constipation, urinary retention, falls, blurred vision
and delirium. Anticholinergic burden refers to the cumulative effect of taking
multiple medications with anticholinergic effects. Over the past few decades
many scales have been developed to measure anticholinergic burden. These scales
usually rank the anticholinergic activity of medications into 3-5 levels, ranging
from no anticholinergic activity (O) to definite anticholinergic activity (3 to
5). There is high variability in existing scales; there is still no consensus on the
definition, and both the number and ranking of the anticholinetgic medications
listed vary considerably between the scales. Also, some scales consider the
impact of different routes of administration when ranking the anticholinergic
activity of medications, while others exclude topical, ophthalmic, and inhaled
preparations. Future imperative is developing of one reference composite
anticholinergic scale which would be a useful tool for clinicians to identify medications
with anticholinergic activity
Učinkovitost hidrolizata kolagena u prevenciji i usporavanju starenja kože
No full textCilj istraživanja.
Brojne znanstvene studije pokazuju da suplementacija pojedinim nutrijentima ima potencijalnu ulogu u modulaciji starenja kože, među njima i kolagen, odnosno njegovi hidrolizati. Glavni cilj predloženog specijalističkog rada je iznjeti sustavni pregled dostupnih kliničkih istraživanja o učincima oralne suplementacije hidroliziranim kolagenom u svrhu poboljšanja znakova starenja kože. Dodatni ciljevi rada su dati cjelovit prikaz osobina i svojstava hidroliziranog kolagena te dostupnih istraživanja o mehanizmima njegovog djelovanja i biodostupnosti.
Metode.
Za izradu ovog teorijskog rada korišteni su znanstveni i stručni radovi dostupni putem baze PubMed.
Rezultati.
Istraživanja pokazuju da per os primjena hidroliziranog kolagena poboljšava kliničke manifestacije zdravlja kože, kroz djelovanje na različite aspekte građe i funkcije kože. Kao rezultat pregleda dostupne literature nameće se zaključak da nisu u potpunosti istraženi mehanizmi djelovanja hidroliziranog kolagena u koži, kao i važnost formulacije kolagena u pripravku.
Zaključak.
Potrebna su i daljna istraživanja kojima bi se definirale smjernice za doziranje i duljinu trajanja primjene hidroliziranog kolagena u svrhu postizanja optimalnog učinka.Objectives.
Numerous studies show that supplementing certain nutrients, including collagen and its hydrolysates, can play a significant role in modulating the process of skin ageing. The main goal of this study was to conduct a systematic review of available clinical research on the anti-age effects of oral supplementation with hydrolyzed collagen Additional goals were to provide a comprehensive overview of the features and characteristics of available hydrolyzed collagen formulations and highlight the current knowledge of its mechanism of action and oral bioavailability.
Methods.
Scientific and professional papers available through the PubMed database were used to prepare this theoretical paper.
Results.
Research shows that per os application of hydrolyzed collagen improves clinical manifestations of skin health, by affecting various aspects of skin structure or function. However, mechanism of the action of hydrolyzed collagen in the skin have not been completely elucidated and neither was the importance of particular collagen formulations in products available in the market.
Conclusions.
Additional research is needed to define guidelines for the optimal dosage and duration of hydrolyzed collagen administration in order to achieve an clinically significant anti-age effect
Evaluation of combined effects of silver and polystyrene nanoparticles on model immune cells
No full textNanotehnologija danas ima ulogu rastuće važnosti u razvoju novih industrijskih i medicinskih proizvoda. Nanočestice srebra (nanoAg) jedne su od najviše istraživanih tipova nanomaterijala za potencijalnu primjenu u medicini zbog svojih izraženih antimikrobnih svojstava. Njihova uporaba u medicinskom kontekstu ograničena je zbog štetnog utjecaja kojeg mogu imati na ljudske stanice i tkiva. Iako je toksičnost nanočestica srebra dobro poznata i istražena, manjkaju informacije o kombiniranim biološkim učincima nanoAg i drugih materijala ili nanomaterijala. Za razvoj novih, sigurnih uređaja i pomagala u kojima se koristi nanoAg, nužno je ispitati zdravstvene rizike koji mogu nastati međudjelovanjem nanoAg i materijala koji se primjenjuju u tim proizvodima. Polistiren je biološki inertan materijal široke industrijske i medicinske primjene, te su zbog toga nanočestice polistirena (nanoPS) odabrane za ispitivanje učinka mješavina nanočestica na modelne stanice ljudskog imunosnog sustava, Jurkat i THP-1. Nanočestice su karakterizirane metodama atomske mikroskopije sila te dinamičkog i elektroforetskog raspršenja svjetlosti. Analiziran je utjecaj nanoAg i nanoPS na preživljenje stanica, pokretanje apoptoze, parametre oksidativnog stresa, oštećenje DNA, pokretanje upalnog odgovora te promjene mehaničkih svojstava stanica. Unos nanočestica vizualiziran je konfokalnim mikroskopom i kvantificiran protočnim citometrom. Pokazano je da nanoAg i nanoPS ne stupaju u interakcije u vodenoj suspenziji ili u staničnom mediju, te da su mješavine nanoAg i nanoPS imale štetniji učinak na stanice Jurkat i THP-1 nego pojedinačne vrste nanomaterijala. Ovi rezultati važan su doprinos razumijevanju učinaka nanomaterijala na ljudsko zdravlje i razvoju novih i sigurnih primjena nanotehnologije u medicini.Nanotechnology has a role of growing importance in development of novel industrial and medical applications. Silver nanoparticles (nanoAg) are some of the most researched types of nanomaterials for potential use in medicine due to their significant antimicrobial properties. Their use in medical applications is limited due to their potential toxicity to human cells and tissue. Although the toxicity of silver nanoparticles is well known, there is a distinct lack of information on combined biological effects of nanoAg and other types of materials or nanomaterials. In order to develop safe nanoAg-enabled products, it is paramount to determine if interactions of nanoAg with other materials could pose additional health hazard compared to nanoAg alone. Polystyrene is a biologically inert material with widespread use in industrial and medical applications, and polystyrene nanoparticles (nanoPS) were used to assess the effects of nanometrial mixtures on model immune cell lines, Jurkat and THP-1. Nanoparticles were characterized using atomic force microscopy, as well as dynamic and electrophoretic light scattering techniques. The effects of nanoAg and nanoPS on cell survival, induction of apoptosis, oxidative stress parameters, DNA damage, immune response and changes in cell mechanical properties were analyzed. Nanoparticle uptake was visualized with confocal microscope and quantified using flow cytometry. Results have shown that nanoAg and nanoPS do not interact in water suspensions or in cell culture media, and that nanoAg/nanoPS mixtures had an augmented, detrimental impact on Jurkat and THP-1 cells compared to individual nanoparticle types. These results present an important contribution for understanding impact of nanomaterials on human health, and for development of novel and safe applications of nanotechnology in medicine
Gastrointestinal stability of polyphenols from complex plant extracts
No full textU kreiranju funkcionalne hrane i dodataka prehrani, sve se češće koriste kompleksni biljni ekstrakti bogati polifenolima koji pokazuju širok spektar poželjnih bioloških učinaka, ponajprije antioksidativnog.
U ovom radu ispitana je antioksidativna učinkovitost i gastrointestinalna stabilnost/biodostupnost polifenola iz različitih formulacija ekstrakata sjemenki grožđa i ekstrakata japanskog dvornika. Cilj istraživanja bio je odabrati ekstrakte koji su pogodni za daljnju primjenu u kreiranju funkcionalne hrane obogaćene polifenolima. Kako bi se odredio potencijal analiziranih ekstrakata kao nutraceutika potrebno je uzeti u obzir njihovu antioksidativnu aktivnost i gastrointestinalnu stabilnost.
Antioksidativna aktivnost analiziranih uzoraka istražena je Folin-Ciocalteu (ukupni redukcijski potencijal) i TEAC metodom (antiradikalna učinkovitost). Gastrointestinalna stabilnost (biodostupnost) polifenola u analiziranim ekstraktima određena je in vitro statičkom simulacijom probave prema optimiranom INFOGEST protokolu.
Različite formulacije ekstrakata sjemenki grožđa bile su međusobno usporedive po vrijednostima antioksidativnog potencijala dok su se analizirani ekstrakti japanskog dvornika značajno razlikovali. Antioksidativni potencijal ekstrakta japanskog dvornika značajno je niži od antiradikalnog potencijala ekstrakta sjemenki grožđa. Polifenolni biljni ekstrakti bili su uglavnom stabilni u simuliranim uvjetima probavnog trakta te je malo smanjenje biodostupnosti polifenola primijećeno samo u jednoj formulaciji ekstrakta sjemenki grožđa.Complex plant extracts rich in polyphenols are being increasingly used as bioactive ingredients in the formulation of functional food and nutritional supplements, due to the wide spectrum of their biological effects, primarily, antioxidant. .
In this paper, antioxidant activity and gastrointestinal stability of polyphenols from different formulations of grape seed extract and Polygonum Cuspidatum extract were investigated. The goal was to establish which extracts were suitable for the further use in designing polyphenol-enriched functional foods. To determine the potential of analysed extracts as nutraceuticals, both, their antioxidant activity and gastrointestinal stability need to be taken into account.
Antioxidant activity of analysed samples was investigated by Folin-Ciocalteu (total reduction potential) and TEAC method (antiradical efficiency). Gastrointestinal stability/bioaccessibility of polyphenols in analysed extracts was determined by in vitro static simulation of digestion according to the optimized INFOGEST protocol
Different formulations of grape seed extracts were comparable to each other in terms of antioxidant potential, while the analysed Polygonum cuspidatum extracts differed significantly. The antioxidant potential of the Polygonum cuspidatum extract was significantly lower in comparison to antiradical potential of the grape seed extract. It was determined that polyphenolic plant extracts were stable under simulated conditions of the digestive tract; the small decrease of the polyphenolic bioaccessibility was observed only in one analysed formulation of grape seed extract
Influence of vitamin D status in the organism on the course of SARS-CoV-2 infection
No full textSARS-CoV-2 uzročnik je najnovije pandemijske zarazne bolesti, COVID-19, koja predstavlja ozbiljan rizik za ljudsko zdravlje. Infekcija SARS-CoV-2 uzrokuje aktivaciju imunosnog sustava i sustavnu hiperinflamaciju što može dovesti do akutnog respiratornog distres sindroma (ARDS), jednog od vodećih uzroka morbiditeta i mortaliteta u bolesnika s teškim oblikom infekcije SARS-CoV-2. Žrtve ARDS-a karakterizira značajan porast IL-6 i IL-1 te oštećenje endotela i povećana propusnost barijera. Aktivacija makrofaga, povezana s citokinskom olujom, potiče disregulaciju urođenog imuniteta, a u vrlo teškim oblicima infekcije dovodi i do oštećenja te zatajenja brojnih organa. Vitamin D i njegov receptor, receptor vitamina D (VDR), imaju ključnu ulogu u infekcijama zbog svog izvanrednog utjecaja na urođene i stečene imunosne odgovore te na suzbijanje upalnog procesa. Vitamin D smanjuje jačinu citokinske oluje te smanjuje sistemski upalni odgovor stimulirajući diferencijaciju regulatornih T stanica. Također, inducira proizvodnju endogenih antimikrobnih peptida koji organizam štite od napadajućeg respiratornog virusa. Zaštitna svojstva suplementacije vitaminom D potkrijepljena su brojnim opservacijskim studijama i meta-analizom kliničkih ispitivanja za prevenciju virusnih akutnih respiratornih infekcija. Imajući navedeno na umu, preporuča se održavanje optimalne razine vitamina D u krvi jer se time pospješuje rad imunosnog sustava koji omogućuje organizmu da se učinkovito izbori sa svim patogenima, uključujući viruse.SARS-CoV-2 is the causative agent of the latest pandemic infectious disease, COVID-19, which constitues a serious risk to human health. SARS-CoV2 infection causes immune activation and systemic hyperinflammation which can lead to acute respiratory distress syndrome (ARDS), one of the leading causes of morbidity and mortality in patients with a severe form of SARS-CoV-2 infection. ARDS victims are characterized by a significant increase in IL-6 and IL-1, as well as endothelial damage and increased barrier permeability. Macrophage activation, associated with the cytokine storm, promotes dysregulation of innate immunity and in very severe forms of infection leads to damage and failure of numerous organs. Vitamin D and its receptor, vitamin D receptor (VDR), exert a critical role in infections due to their remarkable impact on both innate and adaptive immune responses as well as on the suppression of the inflammatory process. Vitamin D reduces the intensity of the cytokine storm and also reduces the systemic inflammatory response by stimulating the differentiation of regulatory T cells. It also induces the production of endogenous antimicrobial peptides that protect the body from attacking respiratory viruses. The protective properties of vitamin D supplementation have been supported by numerous observational studies and by meta-analysis of clinical trials for prevention of viral acute respiratory infections. Considering this, it is recommended to maintain an optimal level of vitamin D in the blood, as this improves the work of the immune system, which enables the body to effectively fight all pathogens, including viruses
Otvaranje i deprotoniranje tiazolidinskog prstena. Računalna DFT studija
No full textThiazolidine, a long-known and thoroughly tested molecule, is a structural part of many commonly used compounds. Among these are penicillin antibiotics, which can be found in the environment in increasing concentrations that already exhibit a number of harmful effects in both environmental and health aspects. In order to find a solution for this problem, in the laboratory where this thesis was made it was discovered that UV light only opens thiazolidine ring in thiazolidine and its derivatives. This discovery requires additional chemical description that cannot be obtained through experiments. Therefore, in this research computational methods were used to gather chemical descriptors for the mentioned process on thiazolidine and its three derivatives. For each derivative, species with open and closed thiazolidine rings were tested, as well as certain constants that describe the transition from one species to another.
All collected results in this work were calculated using Gibbs free energies of optimized structures at b3lyp/6-31G(d,p) and b3lyp/6-311++G(d,p) theoretical level. Solvation energies were obtained using the SMD method. Acidity constants were calculated using six different methods, of which method 5 proved to be the most accurate one. Transition state structure for thiazolidine ring-opening reaction was confirmed by IRC calculation, and the wavelengths of absorption maxima were confirmed by TD-DFT calculations.
The obtained values for acidity and chemical equilibrium constants give a basic insight into the behavior of tested species in water. Global reactivity indexes, accompanied by UV-Vis absorption maxima, show high reactivity for all examined compounds. For all molecules, the ratio of the constants values for the same reactions among the corresponding species is the same. The constants' absolute values for the molecules obtained differ depending on the substituents on the thiazolidine ring, as expected.Tiazolidin, dobro poznata i temeljito ispitana molekula, strukturalni je dio mnogih, često korištenih spojeva. Među takvima su i penicilinski antibiotici, koje nalazimo u okolišu u sve većim koncentracijama koje već sada uzrokuju niz štetnih učinaka u ekološkom i zdravstvenom aspektu. S ciljem pronalaska rješenja za ovaj aktualni problem, u laboratoriju gdje je izrađen ovaj rad otkriveno je da pod utjecajem UV svjetla dolazi do otvaranja tiazolidinskog prstena u tiazolidinu i njegovim derivatima. Ovo otkriće zahtijeva dodatno razumijevanje koje se eksperimentima za ovaj brzi proces ne može dobiti. U tu su svrhu u ovom radu korištene računalne metode te su dobiveni kemijski parametri koji opisuju spomenuti proces na tiazolidinu i trima njegovim derivatima. Za svaki su derivat ispitane specije s otvorenim i zatvorenim tiazolidinskim prstenom, te određene konstante koje opisuju prelazak jedne specije u drugu.
Svi prikupljeni rezultati ovog rada izračunati su pomoću slobodnih Gibbsovih energija optimiziranih struktura na b3lyp/6-31G(d,p) i b3lyp/6-311++G(d,p) teorijskoj razini. Solvatacijske energije dobivene su pomoću SMD metode. Konstante kiselosti izračunate su pomoću šest različitih metoda, od kojih se metoda 5 pokazala najtočnijom. IRC računom potvrđena je struktura prijelaznog stanja reakcije otvaranja tiazolidinskog prstena, a TD-DFT računima valne duljine apsorpcijskih maksimuma.
Dobivene vrijednosti konstanti kiselosti i kemijske ravnoteže daju osnovni uvid u ponašanje specija u vodi. Indeksi reaktivnosti, popraćeni UV-Vis apsorpcijskim maksimumima, pokazuju visoku reaktivnost svih ispitivanih spojeva. Za sve molekule, odnos vrijednosti pojedinih konstanti za iste reakcije među odgovarajućim specijama je isti. Apsolutna vrijednost dobivenih brojki razlikuje se ovisno o supstituentima na tiazolidinskom prstenu, kao što je i očekivano
Validation of sHSS-GC-FID method for determination of organic volatile compounds in orally administered solid herbal dietary supplemets for inflammatory bowel diseases
No full textUpalne bolesti crijeva spadaju u kronične idiopatske upalne bolesti gastrointestinalnog sustava karakterizirane upalama segmenata probavnog trakta s raznolikim kliničkim manifestacijama poput krvavih stolica, proljeva, tenezma, urgencije te grčevitih bolova. Razlikujemo dva entiteta: Crohnovu bolest i ulcerozni kolitis. U pozadini Crohnove bolesti je stanično posredovani Th1 tip imunog odgovora, a kod ulceroznog kolitisa Th2 tip koji generira humoralni imuni odgovor. Od lijekova koji se koriste za liječenje upalnih bolesti crijeva prevladavaju aminosalicilati, kortikosteroidi, imunosupresivi i biološka terapija, no u posljednje vrijeme sve se više pacijenata uključuje uz terapiju i biljne dodake prehrani. Neki od korištenih dodataka prehrani su ekstrakt andrografisa i smola tamjanovca, no svakako najvažnija je kurkuma u čijim podancima se nalazi spoj kurkumin uz koji se povezuje snažno protuupalno, antioksidativno i antimutageno djelovanje.
S obzirom na to da od 1990-ih postoji jak uzlazni trend u korištenju dodataka prehrani, jasno je da se povećao i interes pacijenata i zdravstvenih radnika za njihovu sigurnost i učinkovitost. U usporedbi s lijekovima, dodaci prehrani nisu podvrgnuti istim znanstvenim ispitivanjima i nisu tako striktno regulirani i kontrolirani, stoga se mogu naći proizvodi kontaminirani s teškim metalima, pesticidima i dodanim farmakološkim tvarima. Kod biljnih dodataka prehrani, najveći problem je što često sadržavaju značajnu količinu zaostalih organskih otapala, posebice etanola koji je metabolički aktivan i kao takav predstavlja rizik za pojedine skupine pacijenata. Dakle, potreban je razvoj jedinstvene analitičke metode koja bi mogla brzo i pouzdano odrediti ostatna otapala prisutna u biljnim dodacima prehrani.
Plinska kromatografija je metoda odjeljivanja u kojoj uzorak tijekom unošenja u kolonu trenutno ispari, nakon čega plinovita pokretna faza eluira sastavnice uzorka prolazeći kolonom sa nepokretnom fazom, a odijeljene se sastavnice najčešće dokazuju plamenoionizacijskim detektorom. Iz uzorka je potrebno prvo odvojiti hlapljiva organska otapala u plinovitu fazu, stoga se plinska kromatografija povezuje s metodom headspace uzorkovanja. S obzirom na hlapljivost organskih otapala i značajnu separacijsku sposobnost kapilarnih kolona, plinska kromatografija vodeća je tehnika za njihovo određivanje.
U ovom radu validirana je sHSS-GC-FID metode za određivanje metanola, etanola, acetona, izopropanola, diklormetana, etil acetata i kloroforma u krutim biljnim dodacima prehrani koji se koriste uz terapiju upalnih bolesti crijeva. Ispitivanje parametara selektivnosti, linearnosti, granica dokazivanja i određivanja, preciznosti, točnosti i izdržljivosti dalo je zadovoljavajuće rezultate, te se metoda pokazala prikladnom za određivanje navedenih ostatnih otapala. Validirana metoda primijenjena je za analizu dva uzorka neobrađene usitnjene kurkume u kojima nije pronađeno nijedno ostatno otapalo, što čini ove biljne dodatke prehrani sigurnima za uporabu u liječenju upalnih bolesti crijeva.Inflammatory bowel diseases, which include Crohn's disease and ulcerative colitis, are idiopathic chronical inflammatory diseases of the gastrointestinal tract, characterized by recurrent inflammations of segments of gastrointestinal tract with various clinical manifestations such as blood in the stool, diarrhea, urging and abdominal pain. The pathogenesis of Crohn's disease involves the cell-mediated Th1 immune response, while pathogenesis of ulcerative colitis involves Th2 response which generates humoral immunity. Current drug treatment consists of aminosalicylates, corticosteroids, immunosuppressants and biological therapy, but nowadays more and more patients are turning to herbal therapy because of drug side effects. Some of herbal dietary supplements that are used are extract from green chireta and resin from olibanum-tree, but the most important one is turmeric with its main component curcumin. Numerous pharmacological activities have been reported for curcumin, including anti-inflammatory, antioxidant and anticancer properties.
There is a sharp upward trend in the use of dietary supplements since 1990s, which resulted in widespread interest of health care practitioners and patients in their safety and quality. Comparing to medications, dietary supplements are not subjected to the same scientific scrutiny and are not as strictly regulated and controlled, so they are products sold contaminated with heavy metals, pesticides or prescription drugs. In addition, herbal dietary supplements may contain significant levels of organic volatile compounds, especially ethanol which is metabolically active, so it represents high risk for certain groups of patients. Therefore, development of rapid and reliable method for determination of organic volatile compounds in herbal dietary supplements is much needed.
Gas chromatography is an analytical method in which the sample is loaded onto the head of the column via a heated injection port, where it evaporates, and then a gaseous mobile phase elutes its components flowing through a heated tube coated with a liquid stationary phase. Separated components are usually detected with the flame ionization detector. Gas chromatography may be connected to headspace sampling technique to analyze the samples with complex matrices that also contain non-volatile substances. Due to the volatility of organic solvents and the substantial separating capability of capillary columns, gas chromatography is dominated technique for organic solvents determination.
This work focuses upon validation of sHSS-GC-FID method for simultaneous determination of methanol, ethanol, acetone, isopropanol, dichloromethane, ethyl acetate and chloroform in solid herbal dietary supplements for inflammatory bowel diseases. The method was validated for selectivity, linearity, limits of determination and quantitation, precision, accuracy and robustness. All the results were satisfactory; therefore, the method has proven to be reliable for determination
of these organic volatile compounds. Validated method was used in analysing two different turmeric food products, where none of the organic volatile compounds were found, which has proven their safety in therapeutical use in the inflammatory bowel diseases
Examination of anti-inflammatory activity of selected plant species
No full textU ovome diplomskom radu istražena je protuupalna aktivnost ekstrakata biljnih droga Glycyrrhizae radix, Berberidis radicis cortex, Sylibi maiani fructus i Ehinaceae purpureae herba. Ekstrakti biljnih droga pripremljeni su u netkosičnom biorazgradivom glicerolu. Ispitana je povezanost dobivenih rezultata protuupalnog djelovanja sa sadržajem glicerola i flavonoida u ispitivanim ekstraktima. Rezultati ispitivanja pokazali su znatnu protuupalnu aktivnost biljne droge Glycyrrhizae radix u odnosu na pozitivnu kontrolu, te se to djelovanje može povezati sa sadržajem flavonoida. Preostali biljni ekstrakti pokazali su blago ili pak neznatno djelovanje te nizak sadržaj flavonoida.In this work, anti-inflammatory activity of extracts of herbal drugs Glycyrrhizae radix, Berberidis radicis cortex, Silybi mariani fructus and Ehinaceae purpureae herba was investigated. Herbal drug extracts were prepared in a non-toxic biodegradable solvent glycerol. The correlation of the anti-inflammatory action and flavonoid content in the extracts was investigated. The results show that Glycyrrhizae radix demonstrated significant anti-inflammatory activity in relation to the positive control, and that this action can be associated with the content of flavonoids. The remaining plant extracts showed a slight or insignificant effect and a low content of flavonoids