Provider: - Institution: University of Zagreb. Faculty of Pharmacy and Biochemistry. Department of pharmaceutical technology. - Data provided by Europeana Collections- Ispitano je nastajanje ...inkluzijskih kompleksa lorazepama i risperidona s hidroksipropil-β-ciklodekstrinom (HP-β-CD) u otopini i u čvrstom stanju. U otopinama HP-β-CD različitih pH-vrijednostti lorazepam i risperidon stvaraju inkluzijske komplekse molarnog odnosa ciklodekstrin lijek 1:1. Nastajanje inkluzijskih kompleksa mijenja topljivost lijekova u vodi. Na stabilnost inkluzijskih kompleksa lorazepama i risperidona u otopini HP-β-CD utječe pH-vrijednost medija te prisustvo polimera (hidroksipropilmetilceluloza (HPMC) i karbomer). Inkluzijski kompleksi lorazepama i risperidona u čvrstom stanju pripremljeni su metodom sušenja raspršivanjem i karakterizirani su diferencijalnom pretražnom kalorimetrijom i infracrvenom spektroskopijom s Fourierovim transformacijama.
Lorazepam, risperidon i njihovi inkluzijski kompleksi uklopljeni su u mukoadhezivne mikročestice metodom sušenja raspršivanjem. Kao mukoadhezivni polimeri korišteni su HPMC, karbomer i interpolimerni kompleks HPMC i karbomera. Oblikovane mikročestice karakterizirane su s obzirom na uklapanje djelatne tvari, raspodjelu veličina čestica, vrijednost zeta-potencijala te termoanalitičkom metodom (DSC). Mukoadhezivnost mikročestica ispitana je in situ metodom određivanja rada adhezije. Utvrđeno je da na mukoadhezivnost mikročestica utječe kemijska struktura polimera te prisustvo lijeka, dok je utjecaj HP-β-CD zanemariv.
In vitro oslobađanje lorazepama i risperidona iz mikročestica ograničeno je topljivošću lijekova. Mehanizam oslobađanja lorazepama i risperidona iz mikročestica uključuje difuziju lijeka kroz izbubreni polimerni matriks te eroziju matriksa. HP-β-CD utječe na difuziju lorazepama u izbubrenom polimernom matriksu. Brzo otapanje inkluzijskog kompleksa doprinosi eroziji polimernog matriksa. Zbog toga je oslobađanje lorazepama iz mikročestica oblikovanih s HP-β-CD brže. Istim mehanizmom može se objasniti utjecaj HP-β-CD na oslobađanje risperidona iz mikročestica HPMC. Interakcija risperidona i karbomera ključna je pri oslobađanju lijeka iz mikročestica oblikovanih s karbomerom i interpolimernim kompleksom. Stoga je utjecaj HP-β-CD na oslobađanje risperidona iz mikročestica slabije izražen.
Stvaranje inkluzijskih kompleksa utječe na in vitro difuzibilnost lorazepama i risperidona. Mehanizam djelovanja HP-β-CD kao promotora difuzije lijekova tumači se visokom topljivosti inkluzijskih kompleksa te utjecajem ciklodekstrina na transport lijekova kroz hidrodinamski sloj na površini polupropusne membrane. Stvaranje inkluzijskih kompleksa utječe na brzinu oslobađanja lijekova iz mikročestica, a uslijed toga rastu koncentracije lorazepama i risperidona raspoložive za difuziju. Ove karakteristike mukoadhezivnih mikročestica pružaju potencijal za nazalnu primjenu ispitivanih lijekova i njihov transport u CST i/ili tkivo mozga. Ciklodekstrini i ispitivani polimeri u mikročesticama lorazepama i risperidona mogli bi oblikovati terapijski sustav prikladan za nazalnu primjenu lijekova s učinkom na središnji živčani sustav.- The inclusion complex formation of lorazepam and risperidone with HP-β-CD in solution and in solid state was investigated. In solutions of different pH values risperidone and lorazepam formed inclusion complexes with HP-β-CD. The inclusion complex formation significantly increased risperidone and lorazepam solubility. Media pH value and presence of the polymers (hydroxypropylmethyl cellulose (HPMC) and carbomer) influenced the stability of inclusion complexes. Inclusion complexes of risperidone and lorazepam in solid state were prepared by spray drying and characterised by differential scanning calorimetry (DSC) and FTIR spectroscopy.
Lorazepam, risperidone and their inclusion complexes were incorporated in the mucoadhesive microparticles by spray drying. HPMC, carbomer and interpolymer complex of HPMC and carbomer were used as mucoadhesive components. Prepared microparticles were characterised by determination of drug content, particle size distribution, zeta potential measurement and DSC measurement. Mucoadhesion of the microparticles was investigated by in situ method based on adhesion work measurement. Chemical structure of the polymers and drug entrapment affected the mucoadhesion of the microparticles, while HP-β-CD effect was negligible.
In vitro drug release form microparticles was limited by low water solubility of lorazepam and risperidone. The drug release mechanism included the drug diffusion through hydrated polymer matrix and matrix erosion. HP-β-CD affected the lorazepam release rate by increasing the drug solubility in swollen polymer matrix of the microparticles. HP-β-CD also promoted the matrix erosion and therefore contributed to the drug release. The same mechanism controlled the risperidone release from HPMC microparticles containing HP-β-CD. The drug-carbomer interaction limited the release of risperidone from the microparticles formulated with carbomer and interpolymer complex. Therefore, the influence of HP-β-CD on drug release from this microparticles was less pronounced.
The in vitro diffusion studies were performed using standard Franz-diffusion cell. Thereby nasal absorption of the drugs was simulated. Inclusion complex formation affected lorazepam and risperidone diffusibility by increasing the drug solubility. HP-β-CD acted as a carrier of the lipophilic drugs across the hydrodynamic layer on the membrane surface and increased the drug concentration gradient over the membrane. HP-β-CD in microparticles changed the values of in vitro drug diffusion. Inclusion complex formation affected the drug release rate from the microparticles and therefore higher concentrations of lorazepam and risperidone were available for the diffusion. Above-mentioned characteristics of the mucoadhesive microparticles offer the potential for nasal application of lorazepam and risperidone and their transport to the cerebrospinal fluid and the brain. Cyclodextrins and investigated polymers in lorazepam and risperidone microparticles could formulate suitable drug delivery system for nasal application of psychoactive drugs.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: University of Zagreb. Faculty of Pharmacy and Biochemistry. Department of microbiology. - Data provided by Europeana Collections- Fumonizin B1 (FB1), bovericin (BEA) i ...okratoksin A (OTA) su svjetski rašireni mikotoksini koji izazivaju čitav
niz patoloških promjena in vivo i in vitro, a čije je istodobno pojavljivanje u kukuruzu dokazano na području
Hrvatske. Stoga je u ovom radu ispitan mehanizam djelovanja FB1, BEA i OTA i njihove interakcije u PK 15
stanicama (epitel bubrega svinje), praćenjem preživljavanja stanica, integriteta plazmatske i mitohondrijske
membrane, razine lipidne peroksidacije i antioksidacijskog kapaciteta stanice te stupnja apoptoze i
genotoksičnog učinka niskih koncentracija mikotoksina (0,05 g/mL, 0,5 g/mL i 5 g/mL), tijekom 24 i 48
sati. Fumonizin B1, BEA i OTA su citotoksični za PK 15 stanice što se očituje smanjenjem vijabilnosti i
povećanjem katalitičke aktivnosti laktat dehidrogenaze i glutamat dehidrogenaze ovisno o dozi mikotoksina. Sva
tri mikotoksina u najvećoj koncentraciji značajno stimuliraju lipidnu peroksidaciju, a već pri nižim
koncentracijama smanjuju koncentraciju glutationa u PK 15 stanicama. Fumonizin B1, BEA i OTA uzrokuju
apoptozu PK 15 stanica pri čemu se značajnije morfološke apoptotičke promjene zamjećuju nakon 48-satnog
izlaganja. Okratoksin A ima jače djelovanje na aktivnost kaspaze-3 već nakon 24-satnog tretiranja u
koncentracijama od 0,5 i 5 g/mL, dok BEA i OTA uzrokuju značajnije povećanje aktivnosti ovog enzima
nakon duljeg izlaganja. FB1 i BEA su genotoksični za PK 15 stanice u koncentracijama od 0,5 i 5 g/mL, dok
OTA značajno povećava broj mikronukleusa već kod najmanje koncentracije. Sva tri mikotoksina imaju
klastogeni i aneugeni učinak pri čemu je klastogeno djelovanje OTA i BEA više izraženo. U koncentracijama
0,05 i 0,5 g/mL nakon 24- i 48-satnog izlaganja, kombinacije dva i sva tri mikotoksina mikotoksina pokazuju
uglavnom aditivane a manje sinergističke interakcije što se odražava na smanjenje vijabilnosti, narušavanje
integriteta stanične i mitohondrijske membrane, stimulaciju lipidne peroksidacije i smanjnje antioksidacijskog
kapaciteta te apoptozu i mutagenezu. Nakon 24-satnog izlaganja navedenim kombinacijama u koncentraciji 5
g/mL zapažen je aditivan, sinergistički i antagonistički učinak, a nakon 48-satnog tretmana u istoj koncentraciji
više je izražen antagonizam. Istodobni unos niskih koncentracija ovih mikotoksina putem hrane negativno se
odražava na antioksidacijski sustav te može pridonijeti imunosupresiji, nefrotoksičnosti i karcinogenezi u ljudi i
životinja tijekom dulje izloženosti.- Fumonisin B1 (FB1), beauvericin (BEA) and ochratoxin A are widespread mycotoxins, which cause a great
number of pathological changes in vivo and in vitro. Their co-occurrence was established in maize in Croatia.
The mechanism of action of FB1, BEA and OTA, as well as their interactions, were studied in the PK 15 cells
(porcine kidney epithelial cells). We examined the effects of low concentrations (0.05, 0.5 and 5 g/mL) of
individual and combined mycotoxins on cell viability, mitochondrial and plasma membrane integrity, lipid
peroxidation, antioxidative status, and apoptotic and genotoxic events in PK 15 cells. Decrease of cell viability
and increase of catalytic activity of LDH and GLDH show that FB1, BEA and OTA are cytotoxic to PK 15 cell
in dose dependent manner. Individual treatment of cells with 5 g/mL of FB1, BEA and OTA significantly
stimulated lipid peroxidation, while lower concentrations significantly reduced levels of glutathione. Significant
morphological apoptotic changes were observed after 48 hours of exposure to individual mycotoxins. Ochratoxin
A activated caspase-3 already after 24 hours of treatment with 0.5 and 5 g/mL, while BEA and OTA
significantly affected this enzyme after prolonged exposure. Fumonisn B1 and BEA are genotoxic to PK 15 cells
in concentrations of 0.5 and 5 g/mL, while OTA significantly increased the number of micronuclei already after
treatment with lowest concentrations. All of three mycotoxins mainly act as clastogens. Combined treatment
with two or all of three mycotoxins in concentrations of 0.05 and 0.5 g/mL during 24 and 48 hours, showed
mainly additive and less synergistic interactions on cell viability, mitochondrial and plasma membrane integrity,
stimulation of lipid peroxidation and decrease of antioxidative capacity, apoptotic and genotoxic events in PK 15
cells. After 24 hours of exposure to combined mycotoxins in concentration of 5 g/mL, additive, synergistic and
antagonistic effects were observed, while after 48 hours of exposure to same concentration we observed
antagonism. Simultaneous prolonged exposure to mycotoxins in low dietary concentrations can negatively affect
antioxidant status contributing the immunosuppression, nephrotoxicity and carcinogenicity in animals and
humans.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Cilj istraživanja bio je odrediti potrošnju imipenema, kao i otpornost gram negativnih uzročnika (Pseudomonas aeruginosa, Acinetobacter sp., Klebsiella sp., E. coli, Proteus mirabilis, Serratia ...marcescens, Enterobacter sp.) na imipenem. Gram negativni uzročnici izolirani su u Kliničkoj bolnici "Sestre milosrdnice" 1999. i 2000. godine. Testiranje osjetljivosti na imipenem provedeno je metodom disk difuzije i E-testom. Potrošnja imipenema je izražena u DDD/100 bolničkih dana u istim vremenskim razdobljima. Otpornost na imipenem u Acinetobacter sp. je statistički značajno pala 2000. godine (p=0,0052), a poglavito u prvih šest mjeseci (p=0,021) kada je potrošnja imipenema bila najniža. Otpornost ostalih gram negativnih uzročnika na imipenem nije statistički značajno pala. Rezultati ukazuju na to da bi potrošnja imipenema mogla utjecati na promjene u otpornosti Acinetobacter sp. na imipenem.
Provider: - Institution: University of Zagreb. Faculty of Pharmacy and Biochemistry. Department of pharmaceutical analysis. - Data provided by Europeana Collections- Provedena je botanička i ...fitokemijska karakterizacija vrsta roda Plantago L. iz zapadnog
dijela Hrvatske: P. altissima L., P. argentea Chaix, P. coronopus L., P. holosteum Scop. subsp.
depauperata, P. holosteum Scop. subsp. holosteum, P. holosteum Scop. subsp. scopulorum, P.
lagopus L. i P. maritima L. Utvrđena su morfološko-anatomska obilježja istraživanih biljnih
taksona i detaljno opisana građa listova i stabljika, te oblik i raspored trihoma. Histokemijskim
reakcijama dokazane su trjeslovine, sluzi, glikozidi, alkaloidi i proteini. Primjenom TLC metode i
taložnih reakcija utvrđena je prisutnost iridoida, flavonoida, fenolnih kiselina, trjeslovina,
triterpenskih kiselina, saponina i sterola. Unaprijeđena je MEKC metoda i provedena
karakterizacija iridoidnih sastavnica. Vodeni ekstrakti listova sadržavali su do 0,27% aukubina i
do 1,81% katalpola (P. argentea). U većine uzoraka detektirane su još dvije iridoidne supstancije.
Spektrofotometrijski određen sadržaj polifenolnih spojeva u nadzemnim biljnim organima najveći
je u taksona P. holosteum subsp. holosteum, a trjeslovinama i flavonoidima najbogatiji su
nadzemni dijelovi vrste P. argentea. Primjenom programskog paketa ESKULAP potvrđena je
valjanost analitičkog postupka za određivanje tanina s Folin-Ciocalteusovim fenolnim reagensom.
Reverzno-faznom HPLC analizom uspješno je provedena karakterizacija flavonoida i fenolnih
kiselina u metanolno-vodenim ekstraktima listova. Maseni udjeli tih tvari znatno su varirali među
taksonima: rutin (0,005-0,024%), hiperozid (0,007-0,020%), izokvercitrin (0,020%, P. argentea)
kvercitrin (0,001-0,013%), kvercetin (0,006-0,028%), klorogenska kiselina (0,002-0,115%) i
kavena kiselina (0,001-0,046%). Utvrđena je statistički značajna varijabilnost u distribuciji
analiziranih bioaktivnih tvari među analiziranim vrstama. Eksperimentalni fitokemijski podaci
obrađeni su metodom multivarijatne statistike. Utvrđeno je da se vrsta P. argentea fitokemijski
najviše razlikuje od ostalih taksona i da posjeduje najveći fitoterapijski potencijal od svih
istraživanih vrsta roda Plantago L.- Plantago altissima L., P. argentea Chaix, P. coronopus L., P. holosteum Scop. (subsp. depauperata,
subsp. holosteum and subsp. scopulorum), P. lagopus L. and P. maritima L. were botanically and
phytochemically investigated. Complete morphological and anatomical characterization of leaves and
stems was carried out. Histochemical reactions revealed the presence of tannins, mucilage, glycosides,
alkaloids, inulin and proteins. The existence of iridoids (aucubin and catalpol), flavonoids (rutin, hyperosid,
isoquercitrin, quercitrin and quercetin), saponin substances, triterpenes (oleanolic and ursolic acids) and
sterols (β-sitosterol and stigmasterol) was confirmed using TLC. Micellar electrokinetic chromatography
(MEKC) was used for characterization of iridoid substances. The yield of aucubin and catalpol was up to
0.27% and 1.81% of the dry mass of the leaves, respectively. Besides aucubin and catalpol, two related
compounds were determined in plant samples. The results of spectrometric measurements showed that P.
argentea and P. holosteum subsp. holosteum generally contained the highest amounts of total polyphenols,
tannins and flavonoids, while the lowest contents were measured in samples of P. coronopus.
Mathematical and statistical program ESKULAP was used for the evaluation of the analytical procedure
for tannin determination with Folin-Ciocalteu's phenol reagent. Characterizations of flavonoids and
phenolic acids were successfully performed by reversed phase HPLC. Yields of analysed substances varied
among examined species: rutin (0,005-0,024%), hyperosid (0,007-0,020%), isoquercitrin (0,020%, P.
argentea), quercitrin (0,001-0,013%), quercetin (0,006-0,028%), chlorogenic acid (0,002-0,115%) and
caffeic acid (0,001-0,046%). Experimental phytochemical data were evaluated by cluster analysis.
Significant differences were observed in contents and distribution of iridoids, flavonoids and phenolic acids
between investigated plant species. These substances might be good chemotaxonomical markers in the
study of genus Plantago. The results of present study showed that P. argentea had the highest
phytotherapeutic potential of all examined Plantago species and it could be a good resource of biologically
active compounds.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: - Data provided by Europeana Collections- Įvairūs raštai profesoriui Volfgangui: su prašymu apmokėti užsakytus Vilniaus universiteto vaistinei leidinį „ Россiйскiй ...Медицинскiй Списокъ на 1828-й годъ " ir chemines medžiagas, bei Vilniaus gydytojų tarybos rašto kopija, kurioje nurodomos pasikeitusios kai kurių cheminių medžiagų kainos.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: - Data provided by Europeana Collections- Dalykinio pobūdžio botanikos ir farmakologijos tema: apie siunčiamus riešutų pavyzdžius, augalų rinkimą, piešinius katalogui ?, kt. ...Minimi: X. Smołko Superyor Illuksztan., X. Chełmowski, J. S. Felkierzam, X. Somulewicz Prefekt, X. Dąbrowski kapelan, X. Lukaszewicz, kt.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: - Data provided by Europeana Collections- Vilniaus universiteto rektoriaus susirašinėjimas su farmakologijos profesoriumi J. Volfgangu, kuriame prašoma kartu su adjunktu ...Fonbergu ištirti siunčiamą miltelių mėginį dėl kenksmingų medžiagų būvimo. Pateikiamas tyrimų rezultatas.- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Antibacterial Agents Anderson, Rosaleen; Groundwater, Paul W; Todd, Adam ...
2012
eBook
Antibacterial agents act against bacterial infection either by killing the bacterium or by arresting its growth. They do this by targeting bacterial DNA and its associated processes, attacking ...bacterial metabolic processes including protein synthesis, or interfering with bacterial cell wall synthesis and function. Antibacterial Agents is an essential guide to this important class of chemotherapeutic drugs. Compounds are organised according to their target, which helps the reader understand the mechanism of action of these drugs and how resistance can arise. The book uses an integrated "lab-to-clinic" approach which covers drug discovery, source or synthesis, mode of action, mechanisms of resistance, clinical aspects (including links to current guidelines, significant drug interactions, cautions and contraindications), prodrugs and future improvements. Agents covered include: agents targeting DNA - quinolone, rifamycin, and nitroimidazole antibacterial agents agents targeting metabolic processes - sulfonamide antibacterial agents and trimethoprim agents targeting protein synthesis - aminoglycoside, macrolide and tetracycline antibiotics, chloramphenicol, and oxazolidinones agents targeting cell wall synthesis - β-Lactam and glycopeptide antibiotics, cycloserine, isonaizid, and daptomycin Antibacterial Agents will find a place on the bookshelves of students of pharmacy, pharmacology, pharmaceutical sciences, drug design/discovery, and medicinal chemistry, and as a bench reference for pharmacists and pharmaceutical researchers in academia and industry.
Provider: - Institution: - Data provided by Europeana Collections- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain ...Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
Provider: - Institution: - Data provided by Europeana Collections- Aptiekas darbiniece M. Līce Limbažu Lauvu aptiekā 1930. gadu beigās. J.Prūsa Lauvu aptieka atradās Limbažos Jūras ielā 11. Nama Jūra ...ielā 11 cēlis Edmunds Hanzens (1879-1934), kas ienāca Limbažos no Igaunijas un no pilsētas valdes dabūja zemes gabaliņu. Namu uzcēla divu gadu laikā, pie ieejas durvīm uzstādīja divas betonā izlietas lauvas, nokrāsotas baltā krāsā. Aptiekas koncesiju 1922. gadā ieguva provizors Jēkabs Prūss. 1924. gadā viņš aizgāja aizsaulē, taču aptieka palika Prūsu ģimenes īpašumā. Vēlāk tajā strādāja Prūsa radinieks Teodors Hanzens. 1947. gadā aptieku pārcēla uz Valmieru un iekļāva Valmieras aptiekā- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
