Hexanuclear lanthanide clusters encapsulating a mu(6)-CO32- ion displaying an unusual binding mode

Reaction of hydrated lanthanum halides (Ln=La, Pr and Nd) with LH2 [1-(2-HydroxyPhenyl)-3-(2-thienyl)-1,3-Propanedione] in presence of excess triethylamine with methanol as a solvent resulted in the isolation and structural characterization of a series of novel hexanuclear lanthanide clusters templated by mu(6)-CO32- introduced via spontaneous fixation of atmospheric carbon dioxide depicting a new coordination mode of binding. This particular mode of bridging is a first report of its kind in lanthanide clusters. Magnetic analysis of the praseodymium and neodymium analogue shows strong antiferromagnetic interactions in case of praseodymium and weak antiferromagnetic interactions in case of neodymium

PHYSIOLOGICALLY-BASED PHARMACOKINETIC MODEL FOR PLANT-BASED ANTI-OXIDANT DRUGS

ABSTRACTObjective: A pharmacokinetic study is a cumbersome process in clinical research. It is very important in target validation and in shifting a leadcompound into a drug. Our major objective was to reveal the most important physiochemical characters of the plant-based anti-oxidants in align withhuman physiology. The in silico studies can preferably be the best solution to identify the physiologically-based pharmacokinetic (PBPK) behavior ofthe anti-oxidants.Methods: Anti-oxidants are found in many foods including fruits and vegetables. Few of the important anti-oxidants, i.e. around 10 plant-based antioxidantcompounds were taken for this research. These compounds were evaluated based on their pharmacokinetic parameters. The properties suchas Lipinski's rule of 5, absorption, distribution, metabolism, excretion, and toxicity (ADMET) of the compounds were screened thoroughly with thehelp of tools such as molinspiration and gastroplus.Results: The physiological studies of these compounds had shown different compartmental absorptions of the compound in the human gastrointestinaltract. Certain compounds were found to pass the physiological barriers and had the ability to become a drug. The compounds were filtered using therisk and toxicity factors. These risk factors caused the compounds to fail in the process of becoming a drug.Conclusion: The compounds which passed the PBPK studies were eligible to become a drug. Of the 10 compounds investigated, eugenol, gingerol,zingerone, and geraniol were found to have higher fraction of absorption to become a drug. Out of these compounds, the compounds gingerol andeugenol have shown the best factor of absorption, and hence, have a better probability of becoming a drug.Keywords: Anti-oxidants, Lipinski, Absorption, Distribution, Metabolism, Excretion and toxicity, Physiological properties, GastroPlus, In silico

Redox shield enfolding a magnetic core

Ferrocenyl betadiketones were reacted with hydrated lanthanide trihalides in presence of a base to yield red color solids, whose structures were characterized by single crystal X-ray diffraction technique. Structural analysis revealed the formation of nona- and tetranuclear lanthanide oxo-hydroxo clusters [Dy9(μ4-O)2(μ3-OH)8(μ-Fca)8(Fca)8]−[HN(C2H5)3]+ (1), [Ln4(μ-OH)2(μ-OCH3)4(CH3OH)2(Fctfa)6] Ln = Yb (2), Lu (3), and [Ln4(μ-OH)2(μ-OCH3)4(CH3OH)2(Fcpfa)6] Ln = Yb (4), Lu (5). Magnetism studies revealed that 1 shows slow relaxation of magnetisation. Cyclic voltammetry studies of 1 reveal electrochemically stable quasi reversible oxidation systems whereas 2-5 showed irreversible nature

Effect of coordination geometry on the magnetic properties of a series of Ln2 and Ln4 hydroxo clusters

A series of three isostructural tetranuclear complexes with the general molecular formula [Ln4(µ3-OH)4(L)4(µ2-piv)4(MeOH)4] (Ln = Gd 1, Dy 2 and Ho 3; LH = [1,3-bis(o-methoxyphenyl)-propane-1,3-dione]) were isolated and unambiguously characterized by single crystal XRD. Under similar reaction conditions, simply changing the co-ligand from pivalate to 2,6-bis(hydroxymethyl)-p-cresol (LH'3) led to the isolation of dinuclear Ln(III) complexes with the general molecular formula [Ln2(L)4(µ2-LH'2)2]·4DMF (Ln =Gd 4, Dy 5 and Ho 6). Direct current magnetic susceptibility data studies on the polycrystalline sample of 1-6 and the results reveal the existence of weak antiferromagnetic exchange interactions between the lanthanide ions in 1 which is evident from the spin Hamiltonian (SH) parameters (J1 = −0.055 cm−1 and g = 2.01) extracted by fitting χMT(T). On the other hand, though complex 4 exhibits weak antiferromagnetic coupling ( J1 = −0.048 cm−1 and g = 1.99) between the Gd(III) ions, the χMT (T ) data of complexes 5 and 6 unambiguously disclose the presence of ferromagnetic interactions between Dy(III) and Tb(III) ions at lower temperature. Magnetization relaxation dynamics studies performed on 2 show frequency dependent out-of-phase susceptibility signals in the presence of an optimum external magnetic field of 0.5 kOe. In contrast, complex 5 shows slow magnetization relaxation with an effective energy barrier (Ueff) of 38.17 cm−1 with a pre-exponential factor (τ0) of 1.85 × 10−6 s. The magnetocaloric effect (MCE) of complexes 1 and 4 was extracted from the detailed magnetization measurement and the change in the magnetic entropy (−ΔSm) of 1 and 4 was found to be 25.57 J kg−1 K−1 and 12.93 J kg−1 K−1,respectively, at 3.0 K for ΔH = 70 kOe

HISTORIC REVIEW ON MODERN HERBAL NANOGEL FORMULATION AND DELIVERY METHODS

Chemistry deals with herbal constituents are often coined as phytochemistry. Herbal constituents have profound improvements in drug discovery for several existing diseases. Many of these constituents are restricted from pharmaceutical discoveries due to two important reasons: pharmacodynamics and pharmacokinetics. There are many new technological strategies and comparisons have been studied to improve the herbal discoveries in the pharmaceutical market. This review paper will highlight historical evidence of nanogels which is the most important strategy applied to several herbal medicines with high patience compliance, delivery rate, and efficiency. Nanogels are nanoparticles combined with cross-linked polymer networks with desirable features to carry hydrophilic or hydrophobic drugs in a more stable condition. Nanogels are highly preferred substances for herbal medicine in terms of stability and rapid response to the external stimuli factors. Nanogel can facilitate the herbal products with higher cellular penetration than existing and hence, it proves to be the new dimension for both oral and transdermal drug delivery for several unmet diseases like cancer, diabetes, and chronic disorders. By the way, including the recent technological constituents to herbal drugs, it can possess high bioavailability, low toxicity and enhance the sustained release

Dy2 and Dy4 hydroxo clusters assembled using o-vanillin based Schiff bases as ligands and b-diketone co-ligands: Dy4 cluster exhibits slow magnetic relaxation

The reaction of DyCl3.6H2O with the mixed ligand system consisting of o-vanillin based Schiff base ligand H2L [2-(2-hydroxy-3-methoxybenzylideneamino) phenol], dibenzoylmethane (Ph2acac) and acetylacetone (Acac) in the presence of triethylamine as the base afforded, di and tetranuclear dysprosium hydroxo clusters having formulae [Dy2(L)2(Ph2acac)2(H2O)2]3 (1) and [Dy4(L)4(acac)2(OH)2(H2O)2(C6H5N)4] (2) respectively. The solid state structures of these products were established by Single Crystal X-ray diffraction technique. Magnetism studies reveal Dy4 exhibits slow magnetic relaxation behavior

Myopia Control Dose Delivered to Treated Eyes by a Dual Focus Myopia Control Contact Lens

SIGNIFICANCE Consistent with closed-loop models of regulated eye growth, a successful dual-focus (DF) myopia-control contact lens focused a significant proportion of light anterior to the central retina in eyes of treated children viewing near and distant targets. PURPOSE This study examined the optical impact of a DF contact lens during near viewing in a sample of habitual DF lens wearing children. METHODS Seventeen myopic children aged 14 to 18 years who had completed 3 or 6 years of treatment with a DF contact lens (MiSight 1 Day; CooperVision, Inc., San Ramon, CA) were recruited and fit bilaterally with the DF and a single-vision (Proclear 1 Day; CooperVision, Inc.) contact lens. Right eye wavefronts were measured using a pyramidal aberrometer (Osiris; CSO, Florence, Italy) while children accommodated binocularly to high-contrast letter stimuli at five target vergences. Wavefront error data were used to compute pupil maps of refractive state. RESULTS During near viewing, children wearing single-vision lenses accommodated on average to achieve approximate focus in the pupil center but, because of combined accommodative lag and negative spherical aberration, experienced up to 2.00 D of hyperopic defocus in the pupil margins. With DF lenses, children accommodated similarly achieving approximate focus in the pupil center. When viewing three near distances (0.48, 0.31, and 0.23 m), the added +2.00 D within the DF lens treatment optics shifted the mean defocus from +0.75 to -1.00 D. The DF lens reduced the percentage of hyperopic defocus (≥+0.75 D) in the retinal image from 52 to 25% over these target distances, leading to an increase in myopic defocus (≤-0.50 D) from 17 to 42%. CONCLUSIONS The DF contact lens did not alter the accommodative behavior of children. The treatment optics introduced myopic defocus and decreased the amount of hyperopically defocused light in the retinal image

Accuracy of 1-Hour Plasma Glucose During the Oral Glucose Tolerance Test in Diagnosis of Type 2 Diabetes in Adults : A Meta-analysis

OBJECTIVE One-hour plasma glucose (1-h PG) during the oral glucose tolerance test (OGTT) is an accurate predictor of type 2 diabetes. We performed a meta-analysis to determine the optimum cutoff of 1-h PG for detection of type 2 diabetes using 2-h PG as the gold standard. RESEARCH DESIGN AND METHODS We included 15 studies with 35,551 participants from multiple ethnic groups (53.8% Caucasian) and 2,705 newly detected cases of diabetes based on 2-h PG during OGTT. We excluded cases identified only by elevated fasting plasma glucose and/or HbA(1c). We determined the optimal 1-h PG threshold and its accuracy at this cutoff for detection of diabetes (2-h PG >= 11.1 mmol/L) using a mixed linear effects regression model with different weights to sensitivity/specificity (2/3, 1/2, and 1/3). RESULTS Three cutoffs of 1-h PG, at 10.6 mmol/L, 11.6 mmol/L, and 12.5 mmol/L, had sensitivities of 0.95, 0.92, and 0.87 and specificities of 0.86, 0.91, and 0.94 at weights 2/3, 1/2, and 1/3, respectively. The cutoff of 11.6 mmol/L (95% CI 10.6, 12.6) had a sensitivity of 0.92 (0.87, 0.95), specificity of 0.91 (0.88, 0.93), area under the curve 0.939 (95% confidence region for sensitivity at a given specificity: 0.904, 0.946), and a positive predictive value of 45%. CONCLUSIONS The 1-h PG of >= 11.6 mmol/L during OGTT has a good sensitivity and specificity for detecting type 2 diabetes. Prescreening with a diabetes-specific risk calculator to identify high-risk individuals is suggested to decrease the proportion of false-positive cases. Studies including other ethnic groups and assessing complication risk are warranted.Peer reviewe

Ligand driven assembly of a monoorganooxotin cage from the reactions of organotin precursors with phosphonate ligands

2376-2381The reaction of n-BuSn(OH)2Cl with t-BuP(O)(OH)2 in a 1:2 ratio in refluxing toluene or stirring in acetonitrile at room temperature forms the monoorganooxotin cage, [(n-BuSn)2O{ O2P(OH)-t-Bu}4]2 1 in good yields. The reaction conditions have been varied to optimize the yield of the oxo cluster. An intermediate leading to the formation of 1 has been identified by 31P NMR spectroscopy. Compound 1 can be used as a single-source precursor for the formation of SnP2O7 by a low temperature decomposition process at 750oC. &nbsp