Search results for "IBA"
showing 10 items of 1355 documents
Effect of changes in the cellular energy state on glucose transport activity in Brevibacterium flavum
2000
Abstract The effect of changes in cellular energy state on 6[14C]glucose uptake and activity of the phosphoenolpyruvate:glucose phosphotransferase system (PTS) in Brevibacterium flavum RC 115 cells was investigated. Energy generation in cells was varied by adding an inhibitor of cellular respiration (potassium cyanide) and an uncoupler of oxidative phosphorylation (pentachlorophenol) to the cell culture as well as by changing thiamine concentration in the bacterial growth medium. The results showed that glucose uptake in ‘respiring’ cells was inversely correlated with bacterial respiration activity: uptake declined with excess ATP generation and increased with lower ATP synthesis caused by …
Pirmsskolas vecuma bērnu patstāvības veicināšana celtniecības rotaļās
2018
Darba autore: Inga Branca Darba nosaukums: “Pirmsskolas vecuma bērnu patstāvības veicināšana celtniecības rotaļās” Darba mērķis: Izzināt pirmsskolas vecuma bērnu patstāvības sekmēšanu celtniecības rotaļās Pētījuma mērķis ir izzināt pirmsskolas bērnu patstāvības sekmēšanu celtniecības rotaļās. Pirmajā nodaļā tiks analizētas pedagogu un psihologu teorijas un atziņas par celtniecības rotaļām un to kā sekmēt bērna patstāvību šajās rotaļās. Šajā nodaļā uzzināsim, kas ir patstāvība un kas nepieciešams, lai to attīstu. Tika izvirzīta hipotēze, ka bērnu patstāvības veidošanās celtniecības rotaļā būs veiksmīga, ja bērnam ir brīvi pieejama vieta, materiāli un laiks rotaļai savas ieceres izstrādei. La…
Biomolecule-corona formation confers resistance of bacteria to nanoparticle-induced killing: Implications for the design of improved nanoantibiotics
2018
Abstract Multidrug-resistant bacterial infections are a global health threat. Nanoparticles are thus investigated as novel antibacterial agents for clinical practice, including wound dressings and implants. We report that nanoparticles' bactericidal activity strongly depends on their physical binding to pathogens, including multidrug-resistant primary clinical isolates, such as Staphylococcus aureus , Klebsiella pneumoniae or Enterococcus faecalis . Using controllable nanoparticle models, we found that nanoparticle-pathogen complex formation was enhanced by small nanoparticle size rather than material or charge, and was prevented by 'stealth' modifications. Nanoparticles seem to preferentia…
Synthesis and antimicrobial screening of tetra Schiff bases of 1,2,4,5-tetra (5-amino-1,3,4-thiadiazole-2-yl)benzene
2014
Abstract In the present study, novel tetra Schiff bases were synthesized by condensation of 1,2,4,5-tetra (5-amino-1,3,4-thiadiazole-2-yl)benzene with different aromatic aldehydes. The chemical structures were confirmed by means of IR, 1 H NMR, 13 C NMR, and elemental analysis. All compounds were screened for antibacterial ( Staphylococcus aureus ATCC-9144, Staphylococcus epidermidis ATCC-155, Micrococcus luteus ATCC-4698, Bacillus cereus ATCC-11778, Escherichia coli ATCC-25922, and Pseudomonas aeruginosa ATCC-2853) and antifungal ( Aspergillus niger ATCC-9029 and Aspergillus fumigatus ATCC-46645) activities by paper disc diffusion technique. The minimum inhibitory concentrations (MICs) of …
Three simultaneous dissolution profiles on a solid pharmaceutical formulation by a FIA manifold provided with a single spectrophotometric detector.
2003
This article deals with the simultaneous determination of three dissolution profiles in the same pharmaceutical formulation. The officially proposed procedure from the pharmacopoeias is adapted to the FIA methodology to obtain the officially recommended profile or "global profile", and two "individual" profiles, corresponding to dissolution rate of two different active principles present in the formulation; both drugs have overlapped UV-vis spectra. The simultaneous determination of several profiles is based on the derivative spectra and the zero crossing mathematical procedure for the "individual" profiles of an active principle; the "global" profile of the formulation is obtained from the…
A monolayer of a Cu2+-tetraazamacrocyclic complex on glass as the adhesive layer for silver nanoparticles grafting, in the preparation of surface-act…
2011
International audience; A silane-derivatized tetraaza Cu2+ macrocyclic complex is prepared, which forms monolayers on glass surfaces, capable of allowing the further deposition of a stable monolayer of silver nanoparticles, obtaining by this, surfaces that display an enhanced antibacterial activity against Staphylococcus aureus and Escherichia coli.
Activity–Bioavailability balance in Oral Drug Development for a Selected Group of 6‐Fluoroquinolones
2002
Abstract A nomogram is proposed to select the best candidate in drug development studies with quinolones and is intended to substitute other possible models. The nomogram is referred to as an activity–bioavailability balance (ABB) because it includes the following two criteria: ABB= 1 / gm MIC ( drug candidate ) 1 /gm MIC ( ciprofloxacin ) · F calc \( drug candidate \) F calc ( ciproflaxacin ) . The in vitro activity of a group of 4′ N ‐alkyl‐ciprofloxacin derivatives was determined together with that of ciprofloxacin, initially against some reference strains and subsequently against 159 clinical isolates of eight selected species. The inverse of the geometric mean of the lowest concentrati…
Metal complexes of sulfanilamide derivatives. Crystal structure of [Zn(sulfathiazole)2]·H2O
1993
Abstract The crystal structure of the Zn(sulfathiazole) 2 ·H 2 O complex is reported. The complex crystallizes in the monoclinic space group C 2/ c . The cell dimensions are a = 9.098(3) A, b = 17.871(5) A, c = 14.61(1) A, β = 99.44(6)°, V = 2343(2) A 3 , Z = 4, and D x = 1.68 g/cm 3 . The final conventional R-factor = 0.027 for 2669 “observed” reflections and 191 variables. The Zn ion is surrounded in a regular tetrahedral arrangement by two N amino and two N thiazole atoms pertaining to four sulfathiazole (Hstz) ligands. Each stz anion, acting as a bidentate ligand, chelates to two Zn ions as a bridge through the N thiazole and the N amino atoms. The IR, 13 C NMR in solid state, 1 H NMR, …
Increased circulating and intrahepatic T-cell-specific chemokines in chronic hepatitis C: relationship with the type of virological response to pegin…
2004
Summary Aims : To determine the serum and intrahepatic levels of T-helper-1-associated chemokines in patients with chronic hepatitis C before, during and after peginterferon plus ribavirin combination therapy and to search for correlations with baseline characteristics of hepatitis C virus-related chronic liver disease and type of therapeutic response. Methods : Serum chemokine levels were determined by enzyme-linked immunosorbent assays and intrahepatic chemokine messenger RNA and protein levels were tested by ribonuclease protection assay and immunohistochemistry. Results : Serum and intrahepatic chemokine levels were elevated in all patients with chronic hepatitis C and showed a marked d…
Sesterterpenes and macrolide derivatives from the endophytic fungus Aplosporella javeedii.
2020
Abstract Five sesterterpenes (1–5) including two new compounds (1 and 2), as well as a new (6) and a known macrolide (7) were isolated from the endophytic fungus Aplosporella javeedii. The structures of the new compounds were elucidated by analysis of their 1D and 2D NMR and HRMS data as well as by comparison with the literature. Compound 4 and its acetyl derivatives 4a, 4b, 4c which were prepared by acetylation of 4 exhibited moderate cytotoxicity against the mouse lymphoma cell line L5178Y with IC50 values ranging from 6.2 to 12.8 μM, respectively. Moreover, 4a and 4c exhibited also cytotoxicity against human leukemia (Jurkat J16) and lymphoma (Ramos) cell lines. Compound 7 showed strong …