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A comparative study of different Physicochemical Properties of Some commercially available Paracetamol Tablets
No full textParacetamol is a non-steroidal anti-inflammatory drug frequently presented for relief of pain
and fever. The present study was conducted to access the quality control parameters of three
different brands of paracetamol available in current pharmaceutical market of Thika town
Kenya.
The purpose of the current study was to perform various quality control tests like weight
variations, hardness, friability, disintegrations, assay and dissolution prescribed in official
monograph .The results of the three brands met the prescribed official monograph. All the
brands disintegrated within 15 minutes as per the official monograph
The percentage of active ingredients was in acceptable range. Drug regulatory authority
needs to ensure continuity of quality control parameters of paracetamol. Being an over the
counter drug the, consumption of paracetamol is too high therefore it is important for each
brand to be genuine, good manufactured and well marketed .So additional exploration over
the quality of paracetamol is compulsory for safe human consumption .
Keywords
I. Paracetamol
II. Comparative study
III. In- vitro analysis
IV. Physic chemical test
V. Quality control paramete
Controlling the reactivity of [Pd(II)(N^N^N)Cl]+ complexes using 2,6-bis(pyrazol-2-yl)pyridine ligands for biological application: Substitution reactivity, CT-DNA interactions and in vitro cytotoxicity study
No full textFour [(N^N^N)Pd(II)Cl]+ complexes [chloride-(2,2′:6′,2′′-terpyridine)Pd(II)]Cl (PdL1), [chlorido(2,6-bis(N-pyrazol-2-yl)pyridine)Pd(II)]Cl (PdL2), [chlorido(2,6-bis(3,5-dimethyl-N-pyrazol-2-yl)pyridine)Pd(II)]Cl (PdL3) and [chlorido(2,6-bis(3,5-dimethyl-N-pyrazol-2-ylmethyl)pyridine)Pd(II)]BF4 (PdL4) were synthesized and characterized. The rates of substitution of these Pd(II) complexes with thiourea nucleophiles viz; thiourea (Tu), N,N′-dimethylthiourea (Dmtu) and N,N,N′,N′-tetramethylthiourea (Tmtu) was investigated under pseudo first-order conditions as a function of nucleophile concentration [Nu] and temperature using the stopped-flow technique. The observed rate constants vary linearly with [Nu]; kobs = k2[Nu] and decreased in the order: PdL1 > PdL2 > PdL3 ≫ PdL4. The lower π-acceptability of the cis-coordinated N-pyrazol-2-yl groups (which coordinates via pyrazollic-N π-donor atoms) of the PdL2–4 significantly decelerates the reactivity relative to PdL1. Furthermore, the six-membered chelates having methylene bridge in PdL4 do not allow π-extension in the ligand and introduces steric hindrance further lowering the reactivity. Trends in DFT calculated data supported the observed reactivity trend. Spectrophotometric titration data of complexes with calf thymus DNA (CT-DNA) and viscosity measurements of the resultant mixtures suggested that associative interactions occur between the complexes and CT-DNA, likely through groove binding with high binding constants (Kb = 104 M−1). In vitro MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] cytotoxic activity data showed that PdL1 was the most potent complex against MCF7 breast cancer cells; its IC50 value is lower than that of cisplatin. The results demonstrate how modification of a spectator ligand can be used to slow down the reactivity of Pd(II) complexes. This is of special importance in controlling drug toxicity in both pharmaceutical and biomedical applications
Palladium(II) complexes of tridentate bis(benzazole) ligands: Structural, substitution kinetics, DNA interactions and cytotoxicity studies
No full textReactions of 2,6-bis(benzimidazol-2-yl)pyridine (L1), 2,6-bis(benzoxazol-2-yl)pyridine (L2), and 2,6-bis(benzothiazol-2-yl)pyridine (L3) with [Pd(NCMe)2Cl2] in the presence of NaBF4 afforded the corresponding Pd(II) complexes, [Pd(L1)Cl]BF4, PdL1; [Pd(L2)Cl]BF4, PdL2; [Pd(L3)Cl]BF4, PdL3; respectively, while reaction of bis[(1H-benzimidazol-2-yl)methyl]amine (L4) with [Pd(NCMe)2Cl2] afforded complex [Pd(L4)Cl]Cl, PdL4. Characterisation of the complexes was accomplished using NMR, IR, MS, elemental analyses and single crystal X-ray crystallography. Ligand substitution kinetics of these complexes by biological nucleophiles thiourea (Tu), L-methionine (L-Met) and guanosine 5′-diphosphate disodium salt (5-GMP) were examined under pseudo-first order conditions. The reactivity of the complexes decreased in the order: PdL1 > PdL2 > PdL3 > PdL4, ascribed to electronic effects. Density functional theory (DFT) supported this trend. Studies of interaction of the Pd(II) complexes with calf thymus DNA (CT-DNA) revealed strong binding affinities via intercalative binding mode. Molecular docking studies established associative non-covalent interactions between the Pd complexes and DNA. The in vitro cytotoxic activities of PdL1–PdL4 were assessed in cancer cell lines HeLa and MRC5-SV2 and a normal cell line MRC-5, using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. PdL1 exhibited cytotoxic potency and selectivity against HeLa cell that was comparable to cisplatin's. Complex PdL1, unlike cisplatin, did not significantly induce caspase-dependent apoptosis
An investigation of comparative substitution behavior of bifunctional trans-platinum(II) complexes with symmetric and asymmetric alkylamine ligands
No full textThis study was undertaken to investigate the comparative substitution behavior of mononuclear trans-platinum(II) complexes with symmetric and asymmetric amine ligands. The rate of substitution of the aqua moeities from the complexes trans-[Pt(NH3)2(H2O)2](ClO4)2 (tPt), trans-[Pt(NH3)(NH2C2H5)(H2O)2](ClO4)2 (tPt2H2O), trans-[Pt(NH3)(NH2C3H7)(H2O)2](ClO4)2 (tPt3H2O), [trans-Pt(OH2)2(NH2CH3)2](ClO4)2 (tPtM), and [trans-Pt(OH2)2{NH2CH(CH3)2}2](ClO4)2 (tPtR), by three nucleophiles, namely thiourea (TU), 1,3-dimethylthiourea (DMTU), and 1,1,3,3-tetramethylthiourea (TMTU) was studied under pseudo–first-order conditions as a function of concentration and temperature by stopped-flow spectrophotometry. All the substitution reactions of each of the trans-platinum(II) complexes proceeds by a stepwise mechanism involving rate-determining substitution of the first aqua ligand followed by a fast second substitution step, without any intermediates formed. The reactions were second order overall (rate = kobs[complex] where kobs = k2[nucleophile]), first order in both [complex] and [nucleophile]. The reactivity of the complexes was essentially governed by both steric and electronic factors. Comparing the second-order rate constants for the substitution reactions of the mononuclear diaqua trans-platinum(II) complexes with the thiourea-based nucleophiles, the observed trend follows: tPt > tPt2H2O > tPtM > tPt3H2O > tPtR. This reactivity trend is consistent with the pKa values obtained for the first deprotonation step. The reactivity of the nucleophiles with the complexes decreases with an increase in steric demand in the following order: TU > DMTU > TMTU. The low positive values of activation enthalpy and large negative values of activation entropy indicate an associative mechanism of substitution in all the complexes. The computational modeling using density functional theory calculations was employed to provide theoretical interpretation of kinetic data
Invitro antilipid peroxidation and ferric reducingantioxidant power of methanolic stem bark lonchocarpus eriocalyx
No full textFree radicals are species characterized by unpaired electrons and reactive in nature. These
Species mainly include two broad classes; reactive oxygen (ROS) species and reactive
Nitrogen species (RNS). Under normal condition they have beneficial role that involves cell
Signaling and beneficial oxidation that generates energy. However, under low levels of
Antioxidants or relapse in the antioxidant defense system free radicals are over produced and
They surpass the antioxidant levels. This increase in the free radicals mainly ROS results into
Oxidation reactions that cause deleterious damages on the cell membrane and even may result
Into cell death. One of this oxidation reactions is the lipid peroxidation in which the lipids are
Oxidized by the attack of reactive oxygen species that interferes with the cell membrane
Functions. The free radicals have as well been linked to the genesis of various disorders and
Diseases. The control of these deleterious effects involves eradication of the free radicals.
Antioxidants are used to scavenger these free radicals and the antioxidants of synthetic nature
Have been in use for many years. However, these gents have been associated with side effects
And are expensive. Plants are alternative source of natural antioxidants that are safe and at the
Same time potent. In this study the anti-lipid peroxidation activity and the ferric reducing
Antioxidant power of the methanolic stem bark extract of Lonchocarpus eriocalyx was
Investigated. The anti-lipid peroxidation was assayed by determining the thiobarbituric
Reactive substances (TBARS) while the reducing power was determined by the ferric
Reducing antioxidant power method. In this study L-ascorbic acid was used as the standard
Antioxidant in both assays. The ferric reducing power results showed that the extract recorded
A dose dependent reducing power which increased with increase in the concentration. At
Concentrations 3.125 mg/ml and 1.5625 mg/ml no significant difference in the percentage
Reducing power was noted (p>0.05). However, at the rest of the concentrations of the extract
Significant difference was noted in the percentage reducing power recorded (p<0.05).
Similarly, for the L-ascorbic acid, significant difference in the percentage reducing power
Was noted at 6.25 mg/ml. However, at the other all concentration no significant difference
Was noted between them (p>0.05). At all concentration levels, L-ascorbic acid recorded
Significantly higher reducing power percentage as compared to the extract (p<0.05). The
Methanolic root extract of Lonchocarpus eriocalyx and L-ascorbic acid recorded EC50 values
Of 0.36937 mg/ml and 0.26188 mg/ml respectively. The results for lipid peroxidation
Inhibition showed that at concentrations 12.5 mg/ml and 6.25 mg/ml and 3.125 mg/ml and
1.5625mg/ml no significant difference in percentage inhibition was recorded for both the
Extract and the standard (p>0.05). However, significant difference was noted at
Concentrations 0.3906 mg/ml and 0.7813 mg/ml for both extract and the standard (p<0.05).
The comparison of the peroxidation inhibition activity of the extract to that of standard
Showed that no significant difference was noted at concentration of 12.5 mg/ml (p>0.05).
However, at all other concentrations the standard (L-Ascorbic acid) recorded significantly
Higher percentage inhibition of lipid peroxidation(p<0.05). In conclusion the methanolic stem
Bark extract of Lonchocarpus eriocalyx it’s a potential antioxidant agent with free radical
Scavenging propertie
Correction to: A kinetic investigation of mononuclear trans-platinum(II) complexes with mixed amine ligands
No full textThe article “A kinetic investigation of mononuclear trans-platinum(II) complexes with mixed amine ligands”, written by “Moses Ariyo Olusegun, Desigan Reddy and Deogratius Jaganyi”, was originally published electronically on the publisher’s internet portal https://link.springer.com/article/10.1007/s11243-020-00381-0 on 12 March 2020 with open access. With the author(s)’ decision to step back from Open Choice, the copyright of the article changed on 20 April 2020 to ©Springer Nature Switzerland AG 2020 and the article is forthwith distributed under the terms of copyright
Exploring perspectives on antimicrobial stewardship: a qualitative study of health managers in Kenya
No full textBackground: Antimicrobial resistance is a significant public health concern with the establishment of antimicrobial stewardship in hospitals being obligatory now more than ever. The perspectives and insights of health managers on antimicrobial stewardship, the complementary health services and building blocks are imperative towards implementation of robust antimicrobial stewardship programs.
Methods: A cross-sectional, qualitative, multicenter study was conducted in three hospitals in Kenya. Key-informant, face-to-face interviews with hospital health managers were carried out on their perspectives on antimicrobial stewardship. Qualitative data was captured using audio tapes and field notes, transcribed and managed using QSR Nvivo 12 software. An iterative process was used to develop the thematic framework and updated in two rounds of iteration analysis. Analysis charts for each emergent theme were developed and categorized across all participants.
Results: Perspectives on antimicrobial stewardship are described in five thematic categories; Importance of antimicrobial stewardship and the role of medicines and therapeutics committee, availability of an antimicrobial formulary and usage surveillance systems, Laboratory competency and recommendations for infection prevention and management, Educational resources and communications channels available, Building blocks and low-lying fruits for ASCs. The role of stewardship collaboration in diagnosis and antimicrobial prescription was alluded to with managers indicating a growing rise in occurrence of antimicrobial resistance. There was no contextualized, hospital specific antimicrobial formulary based on the local antibiograms in any of the hospitals. Lack of adequate laboratory competency was a major deficit with most hospitals lacking culture and sensitivity testing services. Staff training and communication channels were available in varying capacity across the three hospitals. Building blocks identified include medicines and therapeutics committee, education and training platforms (CMEs and CPDs) and hospital leadership commitment towards antimicrobial stewardship.
Conclusions: The findings underpin the importance of understanding and incorporating the perspectives of health managers on the existing contextual mechanisms that can be leveraged on to establish robust AMS programs in the fight against AMR
Global Repertoire of Human Antibodies Against Plasmodium falciparum RIFINs, SURFINs, and STEVORs in a Malaria Exposed Population
No full textClinical immunity to malaria develops after repeated exposure to Plasmodium falciparum parasites. Broadly reactive antibodies against parasite antigens expressed on the surface of infected erythrocytes (variable surface antigens; VSAs) are candidates for anti-malaria therapeutics and vaccines. Among the VSAs, several RIFIN, STEVOR, and SURFIN family members have been demonstrated to be targets of naturally acquired immunity against malaria. For example, RIFIN family members are important ligands for opsonization of P. falciparum infected erythrocytes with specific immunoglobulins (IgG) acquiring broad protective reactivity. However, the global repertoire of human anti-VSAs IgG, its variation in children, and the key protective targets remain poorly understood. Here, we report wheat germ cell-free system-based production and serological profiling of a comprehensive library of A-RIFINs, B-RIFINs, STEVORs, and SURFINs derived from the P. falciparum 3D7 parasite strain. We observed that >98% of assayed proteins (n = 265) were immunogenic in malaria-exposed individuals in Uganda. The overall breadth of immune responses was significantly correlated with age but not with clinical malaria outcome among the study volunteers. However, children with high levels of antibodies to four RIFINs (PF3D7_0201000, PF3D7_1254500, PF3D7_1040600, PF3D7_1041100), STEVOR (PF3D7_0732000), and SURFIN 1.2 (PF3D7_0113600) had prospectively reduced the risk of developing febrile malaria, suggesting that the 5 antigens are important targets of protective immunity. Further studies on the significance of repeated exposure to malaria infection and maintenance of such high-level antibodies would contribute to a better understanding of susceptibility and naturally acquired immunity to malaria
