We describe here the extraction and identification of several classes of phenolic compounds from the lichens
Parmotrema dilatatum (Vain.) Hale,
Parmotrema tinctorum (Nyl.) Hale,
Pseudoparmelia ...sphaerospora (Nyl.) Hale and
Usnea subcavata (Motyka) and determined their anti-tubercular activity. The depsides (atranorin, diffractaic and lecanoric acids), depsidones (protocetraric, salazinic, hypostictic and norstictic acids), xanthones (lichexanthone and secalonic acid), and usnic acid, as well seven orsellinic acid esters, five salazinic acid 8’,9’-
O-alkyl derivatives and four lichexanthone derivatives, were evaluated for their activity against
Mycobacterium tuberculosis. Diffractaic acid was the most active compound (MIC value 15.6
μg/ml, 41.6
μM), followed by norstictic acid (MIC value 62.5
μg/ml, 168
μM) and usnic acid (MIC value 62.5
μg/ml, 182
μM). Hypostictic acid (MIC value 94.0
μg/ml, 251
μM) and protocetraric acid (MIC value 125
μg/ml, 334
μM) showed moderate inhibitory activity. The other compounds showed lower inhibitory activity on the growth of
M. tuberculosis, varying from MIC values of 250 to 1370
μM.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
BACKGROUND AND PURPOSE We investigated the effect of the phosphodiesterase‐5 inhibitor, tadalafil, on the acute hypernociception in rat models of arthritis.
EXPERIMENTAL APPROACH Rats were treated ...with either an intra‐articular injection of zymosan (1 mg) or surgical transection of the anterior cruciate ligament (as an osteoarthritis model). Controls received saline intra‐articular or sham operation respectively. Joint pain was evaluated using the articular incapacitation test measured over 6 h following zymosan or between 4 and 7 days after anterior cruciate ligament transection. Cell counts, tumour necrosis factor‐α (TNF‐α), interleukin‐1 (IL‐1), and the chemokine, cytokine‐induced neutrophil chemoattractant‐1 (CINC‐1) were measured in joint exudates 6 h after zymosan. Groups received tadalafil (0.02–0.5 mg·kg−1per os) or saline 2 h after intra‐articular zymosan. Other groups received the µ‐opioid receptor antagonist naloxone or the cGMP inhibitor 1H‐1,2,4 oxadiazolo 4,3‐a quinoxalin‐1‐one (ODQ) before tadalafil.
KEY RESULTS Tadalafil dose‐dependently inhibited hypernociception in zymosan and osteoarthritis models. In zymosan‐induced arthritis, tadalafil significantly decreased cell influx and TNF‐α release but did not alter IL‐1 or CINC‐1 levels. Pretreatment with ODQ but not with naloxone prevented the anti‐inflammatory effects of tadalafil.
CONCLUSIONS AND IMPLICATIONS Therapeutic oral administration of tadalafil provided analgesia mediated by guanylyl cyclase and was independent of the release of endogenous opioids. This effect of tadalafil was associated with a decrease in neutrophil influx and TNF‐α release in inflamed joints.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Background and Purpose
Intestinal mucositis is a common side‐effect of irinotecan‐based cancer chemotherapy regimens. This mucositis is associated with cytokine activation and NO synthesis. ...Production of IL‐18 is up‐regulated in patients suffering from inflammatory bowel disease. Therefore, we have investigated the role of IL‐18 in the pathogenesis of irinotecan‐induced intestinal mucositis.
Experimental Approach
Wild type (WT), IL‐18 or caspase‐1 knockout mice were treated with either saline or irinotecan (60 mg·kg−1 per 4 days, i.p.) or the IL‐18 binding protein (IL‐18bp, 10 mg·kg−1) before irinotecan. On day 5, diarrhoea was monitored and proximal intestinal strips were obtained for histopathology, in vitro gut contractility, myeloperoxidase (MPO) and inducible NOS (iNOS) activity, and detection of IL‐18 expression.
Key Results
Irinotecan induced severe diarrhoea accompanied by intestinal injury (villi shortening and increased crypt depth). Additionally, irinotecan treatment increased MPO and iNOS activity, iNOS immunostaining and IL‐18 expression in WT mice compared with saline treatment. The IL‐18 production was associated with macrophages. In vitro, intestinal smooth muscle strips were hyperresponsive to ACh after irinotecan treatment. Increases in MPO and iNOS activity, intestinal contractility and diarrhoea were prevented in caspase‐1 knockout and IL‐18 knockout mice, and in IL‐18bp‐treated WT mice. Furthermore, the Survival of irinotecan‐treated mice was increased and iNOS immunoexpression and IL‐18 production prevented in IL‐18 knockout mice.
Conclusions and Implications
Targeting IL‐18 function may be a promising therapeutic approach to decreasing the severity of intestinal mucositis during irinotecan treatment regimens.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Over time, oil production in a reservoir tends to decrease, which makes it difficult to flow through the reservoir to the well, making its production increasingly difficult and costly. Due to their ...physical properties, such as reducing the water/oil interfacial tension, surfactants have been used in enhanced oil recovery (EOR) processes, however, their adsorption presents as an undesirable and inevitable factor and can decrease the efficiency of the method. This work’s main objective is to evaluate the effect of glycerol in the adsorption of surfactants in sandstones, as well as in the recovery factor during EOR. Brine solutions containing the nonionic surfactant saponified coconut oil (SCO), with and without glycerol, were used in the adsorption and oil recovery tests in sandstone. Adsorption, recovery, rheological, and thermogravimetric analysis were carried out. Regarding the surfactant/glycerol/brine solution, there was an improvement in the oil mobility, as the glycerol contributed to an increase in the viscosity of the solution, thereby increasing the sweep efficiency. The recovery factor obtained for the surfactant solution with glycerol was satisfactory, being 53% higher than without glycerol, because it simultaneously provided an increase in viscosity and a decrease in interfacial tension, both of which are beneficial for the efficiency of the process.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Through a systematic variation on the structure of a series of manganese complexes derived from 2-acetylpyridine-N(4)-R-thiosemicarbazones (Hatc-R), structural features have been investigated with ...the aim of obtaining complexes with potent anti-Mycobacterium tuberculosis activity. The analytical methods used for characterization included FTIR, EPR, UV–visible, elemental analysis, cyclic voltammetry, magnetic susceptibility measurement and single crystal X-ray diffractometry. Density functional theory (DFT) calculations were performed in order to evaluate the contribution of the thiosemicarbazonate ligands on the charge distribution of the complexes by changing the peripheral groups as well as to verify the Mn–donor atoms bond dissociation predisposition. The results obtained are consistent with the monoanionic N,N,S-tridentate coordination of the thiosemicarbazone ligands, resulting in octahedral complexes of the type Mn(atc-R)2, paramagnetic in the extension of 5 unpaired electrons, whose EPR spectra are consistent for manganese(II). The electrochemical analyses show two nearly reversible processes, which are influenced by the peripheral substituent groups at the N4 position of the atc-R1− ligands. The minimal inhibitory concentration (MIC) of these compounds against M. tuberculosis as well as their in vitro cytotoxicity on VERO and J774A.1 cells (IC50) was determined in order to find their selectivity index (SI) (SI=IC50/MIC). The results evidenced that the compounds described here can be considered as promising anti-M. tuberculosis agents, with SI values comparable or better than some commercial drugs available for the tuberculosis treatment.
Thiosemicarbazone manganese(II) complexes of the type Mn(atc-R)2 (Hatc-R=2-acetylpyridine-N(4)-R-thiosemicarbazone) were investigated by several techniques. The high activities against Mycobacterium tuberculosis (MTB) and low in vitro cytotoxicity to VERO and J774 cells presented by these complexes place them on the rank of potential anti-tuberculosis drug candidates. Display omitted
•The anti-Mycobacterium tuberculosis (MTB) activity of Mn(II) complexes is probed.•The Mn(II) compounds present two reversible redox processes in the voltammetry.•DFT calculations are compared with experimental data.•The complexes show low in vitro cytotoxicity against VERO and J774A.1 cells.•A promising candidate for tuberculosis treatment is identified.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract A series of 4-amino-7-chloroquinoline derivatives were synthesized by the reaction of 4,7-dichloro-quinoline with the corresponding diamine and then with propargyl bromide. In addition, ...platinum(II) complexes were obtained by reacting some of the organic derivatives with K2 PtCl4 . Several of the synthesized compounds displayed antituberculosis activities. Compound 3 was 47.5 times more active than amphotericin B against Leishmania chagasi (IC50 = 0.04 μg/mL). Compounds 5, 6, 7, 9, 10, 11 and 13 presented promising results against Mycobacterium tuberculosis , with MIC values ranging from 12.5 to 15.6 μg/mL, comparable to the “first and second line” drugs used to treat tuberculosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The reactions between Pd(
C
2,
N-dmba)(μ-X)
2 (dmba
=
N,
N-dimethylbenzylamine; X
=
Cl, Br) and thiourea (tu) in the 1:2 molar ratio at room temperature resulted in the mononuclear compounds Pd(
C
2,
...N-dmba)(Cl)(tu) (
1) and Pd(
C
2,
N-dmba)(Br)(tu) (
2), which were characterized by elemental analyses and infrared (IR),
1H- and
13C{
1H} NMR spectroscopies. The crystal and molecular structures of
2 were determined by single-crystal X-ray diffraction. In vitro cytotoxicity assays of the compounds
1,
2, tu, dmba and cisplatin were carried out using two murine tumor cell lines, namely mammary adenocarcinoma (LM3) and lung adenocarcinoma (LP07). The compounds
1,
2, tu and dmba were also tested against
Mycobacterium tuberculosis and their MIC values were determined.
Display omitted The antitumor and antitubercular activities of the compounds Pd(
C
2,
N-dmba)(X)(tu) {dmba
=
N,
N-dimethylbenzylamine; X
=
Cl (
1), Br (
2)} were evaluated in this work.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Two new complexes of platinum(II) and silver(I) with acesulfame (ace) were synthesized. The structures of K
2PtCl
2(ace)
2 and Ag(ace)
n
were determined by X-ray crystallography. Antitumoral, ...antibacterial and antiviral studies were evaluated and the compounds showed a good activity, especially against
Mycobacterium tuberculosis
and dengue virus type 2 (
New Guinea C strain).
Two new complexes of platinum(II) and silver(I) with acesulfame were synthesized. Acesulfame is in the anionic form acesulfamate (ace). The structures of both complexes were determined by X-ray crystallography. For K
2PtCl
2(ace)
2 the platinum atom is coordinated to two Cl
− and two
N-acesulfamate atoms forming a
trans-square planar geometry. Each K
+ ion interacts with two oxygen atoms of the S(
O)
2 group of each acesulfamate. For the polymeric complex Ag(ace)
n
the water molecule bridges between two crystallographic equivalent Ag1 atoms which are related each other by a twofold symmetry axis. Two Ag1 atoms, related to each other by a symmetry centre, make bond contact with two equivalent oxygen atoms. These bonds give rise to infinite chains along the unit cell diagonal in the ac plane. The
in vitro cytotoxic analyses for the platinum complex using HeLa (human cervix cancer) cells show its low activity when compared to the vehicle-treated cells. The Ag(I) complex submitted to
in vitro antimycobacterial tests, using the Microplate Alamar Blue (MABA) method, showed a good activity against
Mycobacterium tuberculosis, responsible for tuberculosis, with a minimal inhibitory concentration (MIC) value of 11.6
μM. The Ag(I) complex also presented a promising activity against Gram negative (
Escherichia coli and
Pseudomonas aeruginosa) and Gram positive (
Enterococcus faecalis) microorganisms. The complex K
2PtCl
2(ace)
2 was also evaluated for antiviral properties against dengue virus type 2 (
New Guinea C strain) in Vero cells and showed a good inhibition of dengue virus type 2 (
New Guinea C strain) replication at 200
μM, when compared to vehicle-treated cells.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Background and purpose: We investigated the effect of nitric oxide synthase (NOS) inhibition on polymorphonuclear cell (PMN) influx in zymosan or lipopolysaccharide (LPS)‐induced arthritis and ...peritonitis.
Experimental approach: Wistar rats received intra‐articular (i.art.) zymosan (30–1000 µg) or LPS (1–10 µg). Swiss C57/Bl6 mice genetically deficient in intercellular adhesion molecule‐1 (ICAM‐1−/−) or in β2‐integrin (β2‐integrin−/−) received zymosan either i.art. or i.p. PMN counts, leukotriene B4 (LTB4), tumour necrosis factor‐α (TNF‐α) and interleukin‐10 (IL‐10) levels were measured in joint and peritoneal exudates. Groups received the NOS inhibitors NG‐nitro‐L‐arginine methyl ester (LN), nitro‐L‐arginine, N‐3‐(aminomemethyl)benzyl acetamide or aminoguanidine, prior to zymosan or LPS, given i.p. or s.c. in the arthritis and peritonitis experiments respectively. A group of rats received LN locally (i.art. or i.p.), 30 min prior to 1 mg zymosan i.art.
Key results: Systemic or local NOS inhibition significantly prevented PMN migration in arthritis while increasing it in peritonitis, regardless of stimuli, concentration of NOS inhibitors and species. NOS inhibition did not alter TNF‐α and IL‐10 but decreased LTB4 in zymosan‐induced arthritis. LN administration significantly inhibited PMN influx into the joints of ICAM‐1−/− and β2‐integrin−/− mice with zymosan‐arthritis, while not altering PMN influx into the peritoneum of mice with zymosan‐peritonitis.
Conclusions and implications: Nitric oxide has a dual modulatory role on PMN influx into joint and peritoneal cavities that is stimulus‐ and species‐independent. Differences in local release of LTB4 and in expression of ICAM‐1 and β2‐integrin account for this dual role of NO on PMN migration.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
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