Photodelivery of CO by designed PhotoCORMs: correlation between absorption in the visible region and metal-CO bond labilization in carbonyl complexes

The therapeutic potential of photoactive CO-releasing molecules (photoCORMs) have called for close examination of the roles of the ligand(s) and the central metal atoms on the overall photochemical labilization of the metal-CO bonds. Along this line, we have synthesized four metal complexes, namely, [MnBr(azpy)(CO)3 ] (1), [Mn(azpy)(CO)3 (PPh3 )]ClO4 (2), [ReBr(azpy)(CO)3 ] (3), and [Re(azpy)(CO)3 (PPh3 )]ClO4 (4), derived from 2-phenylazopyridine. These complexes were characterized by spectroscopic and crystallographic studies. Although both 1 and 3 exhibit strong metal-to-ligand charge-transfer bands in the 500-600 nm region, only 1 photoreleases CO upon illumination with visible light. Results of theoretical studies were used to gain insight into this surprising difference. Strong spin-orbit coupling (prominent in heavy metals) appears to promote intersystem crossing to a triplet state in 3, a step that discourages CO release upon illumination with visible light. Slow release of CO from 2 and 4 also indicates that strong σ-donating ligands, such as Br(-) , accelerate the rate of CO photorelease relative to π-acid ligands, such as PPh3 .

Value addition of Palmyra palm and studies on the storage life

Palmyra palm (Borassus flabellifer L.) belonging to the family Palmae is referred to as tree of life with several uses including food, beverage, fibre, medicinal and timber. Unfortunately, the nutritionally enriched pulp of ripened palm has limited commercial use. Extraction of pulp has been accomplished by using water and heat to ensure maximum pulp recovery. Different recipes were tried for the preparation of two uncommon value added products like palm spread and palm toffee. On the basis of biochemical composition, organoleptic scores, microbial estimation and storage study both under ambient and refrigerated conditions; the suitable recipe was selected with the maximum acceptability. Gradual increase in total soluble solid (TSS), total sugar and reducing sugar while decrease in ascorbic acid, pH, β-carotene and protein content of processed products have been observed irrespective of storage condition. The results obtained from sensory evaluation and microbial status revealed that palm spread and toffee remained acceptable up to 9 months and 8 months, respectively at ambient temperature. The income per rupee investment for these two products was found to be remunerative.

Assessment of stress & related albuminuria in caregivers of severe mentally ill persons

BACKGROUND & OBJECTIVES

The family caregivers of patients with chronic diseases are known to undergo psychiatric stress leading to oxidative damage to glomerular membrane of kidney resulting in proteinuria. This study was aimed to compare current anxiety, depression levels and urinary albumin:creatinine ratio between primary caregivers of chronic mental patients and matched controls, and also whether the urinary albumin : creatinine ratio is correlated with stress factors (state and trait anxiety level, depression and caregiver burden) amongst caregivers.

METHODS

The present cross-sectional study included 131 subjects (93 primary caregivers of patients with major mental illness as cases and 38 normal controls). They completed the Burden Assessment Schedule of SCARF, State Trait Anxiety Inventory and Beck's Depression Inventory. A spot urine sample was tested for urinary albumin : creatinine ratio from all study subjects.

RESULTS

Mean values of current State and Trait anxiety, depression, urinary albumin:creatinine ratio were significantly higher in caregivers than controls (P < 0.001). Urinary albumin : creatinine ratio was significantly correlated (P < 0.001) with State and Trait anxiety level, depression as well as caregiver burden.

INTERPRETATION & CONCLUSIONS

The study demonstrated depression , anxiety and albuminuria amongst primary caregivers of patients with mental illness. Increase in the caregivers' burden, depression and anxiety resulted in an increase in the urinary albumin: creatinine ratio. This indicates that psychological stress is one of the determinants of albumin excretion rate in otherwise healthy subjects.

Determination of coverage interval of antioxidant vitamins (vitamin C & vitamin e) in plasma and serum of bengali population

Reference interval of all haematological and biological analytes should be measured for every population because of the huge diversity in genetic make-up, dietary habits. The coverage interval of antioxidant vitamins (vitamin C and α -tocopherol) in the plasma and serum of reference Bengali population was determined and compared with the reference intervals of antioxidant vitamins in the established literature. Adult healthy volunteers from 18 to 68 years of age underwent extensive clinical and investigational procedure and were included in the study. Vitamin C and α -tocopherol were estimated using simple Spectrophotometric method. Of the 71 healthy Bengali volunteers participated, 31 were males and 40 were females. The mean concentration of plasma vitamin C was found to be 0.65 mg/dL. The mean α -tocopherol was found 6.35 mg/L (14.74  μ mol/L) in the study population higher than the normal threshold value for α -tocopherol but lower than other populations. The study data enabled us to determine the gender nonspecific coverage interval of antioxidant vitamins, and the intervals were lower than the established reference interval in other populations.

Water-Soluble Derivatives of Octanuclear Iron-Oxo-Pyrazolato Complexes; An Experimental and Computational Study

Two water-soluble iron-pyrazolato complexes, [Fe8], have been prepared by the introduction of twelve hydroxyalkyl groups to the periphery of the approximately spherical octanuclear molecule and they are contrasted with their two organosoluble chloroalkyl analogues. All four new complexes, 1 - 4, have been characterized in solution by 1H-NMR and electrospray ionization mass spectroscopy. The one-electron reduction product of the water-soluble 3, [Fe8]-, has been structurally characterized by single crystal diffraction methods. In aqueous media, the four terminal Fe-Cl bonds of [Fe8] are partially hydrolysed and the resulting chloro/aqua/hydroxo species form supramolecular nanoscale aggregates, as determined by dynamic light scattering and electron microscopy. Preliminary computational studies by density functional theory methods have been employed in order to model the H-bonding interactions controlling the competing solvation and aggregation processes.

Experimental and theoretical Mössbauer study of an extended family of [Fe8(μ4-O)4(μ-4-R-px)12X4] clusters

Six [Fe(8)(μ(4)-O)(4)(μ-4-R-pyrazolato)(12)X(4)] complexes containing an identical Fe(8)(μ(4)-O)(4) core have been structurally characterized and studied by Mössbauer spectroscopy. In each case, an inner μ(4)-O bridged Fe(III) cubane core is surrounded by four trigonal bipyramidal iron centers, the two distinct sites occurring in a 1:1 ratio. The Mössbauer spectrum of each of the clusters consists of two quadrupole doublets, which, with one exception (X = NCS, R = H), overlap to give three absorption lines. The systematic variation of X and R causes significant changes in the Mössbauer spectra. A comparison with values for the same clusters computed using density functional theory allows us to establish an unequivocal assignment of these peaks in terms of a nested model for the overlapping doublets. The changes in Mössbauer parameters (both experimental and computed) for the 1-electron reduced species [Fe(8)(μ(4)-O)(4)(μ-4-Cl-pyrazolato)(12)Cl(4)](-) are consistent with a redox event that is localized within the cubane core.

Iodine deficiency disorder among pregnant women in a tertiary care hospital of Kolkata, India

The present unicentric, hospital based, non-interventional, cross-sectional study was undertaken to assess the iodine status of pregnant women attending the antenatal clinic at a medical college in Kolkata, India, during the different trimesters of pregnancy and to compare their iodine status with those of age-matched non-pregnant control women. Assessment of the iodine status was based on urinary iodine excretion (UIE). Serum levels of free triiodithyronine (fT3), free thyroxine (fT4) and thyroid stimulating hormone (TSH) were assayed as an indirect measure of iodine status. A statistical comparison between the median values for UIE, TSH, fT4 and fT3 in pregnant women and non-pregnant controls revealed a significant difference between the median values for UIE (p < 0.0047), TSH (p < 0.00001) and fT4 (p < 0.001). UIE and fT4 were significantly lower and TSH was significantly higher in pregnant women than in non-pregnant controls. However, no significant difference in median values for fT3 concentration between the groups was seen (p = 0.4). Only 4 cases out of 200 pregnant women had an UIE of less than the lower cut-off value for UIE recommended by the WHO corresponding to optimal iodine intake. The results indicate most pregnant subjects attending the antenatal clinic at Medical College Kolkata, India, a tertiary care institution, did not suffer from significant iodine depletion. This may be ascribed to increased awareness of this condition and the accessibility of iodized salt among the study population.

"Systematic Synthesis of a Metal Organic Framework Based on Triangular Cu(3)(μ(3)-OH) Secondary Building Units: From a 0-D Complex, to an 1-D Chain and a 3-D Lattice"

Reactions of Cu(CF(3)SO(3))(2) and pyrazole in methanolic solutions in the presence of stoichiometric amounts of py, py/4,4'-bpy, or 4,4'-bpy have yielded two new complexes [Cu(3)(μ(3)-OH)(μ-pz)(3)(py)(3)](CF(3)SO(3))(2)·0.5H(2)O (1) and [{Cu(3)(μ(3)-OH)(μ-pz)(3)(py)(2)}(2)(μ-4,4'-bpy)](CF(3)SO(3))(4) (2), a one-dimensional coordination polymer, {[Cu(3)(μ(3)-OH)(μ-pz)(3)(py)(μ-4,4'-bpy)](CF(3)SO(3))(2)·0.5H(2)O}(n) (3), and a three-dimensional, eight-fold interpenetrated extended lattice, {[Cu(3)(μ(3)-OH)(μ-pz)(3)(μ-4,4'-bpy)(1.5)](CF(3)SO(3))(2)·1.5H(2)O}(n) (4).

Physicochemical and conformational studies on BSA-surfactant interaction in aqueous medium

In this paper, results of physicochemical studies on the interaction of bovine serum albumin (BSA) with alkyltrimethylammonium bromide (ATAB), pentaethylene glycol mono-n-dodecyl ether (C12E5), and sodium dodecyl sulfate (SDS) under the experimental conditions of phosphate buffer at pH 7 in the presence of 10 mM sodium bromide (NaBr), maintaining the ionic strength of the overall solution at micro = 0.015 M, have been presented and discussed. Here, BSA-ATAB corresponds to a polyion-surfactant system bearing opposite charges. BSA precipitated out of the solution on addition of ATAB solution over a certain range of ATAB concentration, the concentration range being dependent on the particular member of the ATAB family. In our earlier reports on the precipitation of oppositely charged polymer-surfactant, the tensiometric profile for surfactant addition in polymer solution differed significantly from that expected from addition of surfactant in the dispersion medium. In the present study, the precipitation process could hardly affect the smoothness of the tensiometric profile. This indicates the interaction process is operative in bulk solution. Microcalorimetric profiles also evidenced an extra hump in the interaction profile at lower surfactant concentrations, without much affecting the dilution enthalpograms beyond micellization. This interaction appeared unimodal and the extent of interaction increased with increasing tail length of ATAB, evidencing the hydrophobic effect to be an important factor. Addition of salt (NaBr) also affected the nature of interaction: at lower concentration of NaBr, the interaction was mildly assisted, whereas 50 mM NaBr fairly assisted the interaction. The nonionic surfactant C12E5 modestly interacted with BSA. The anionic amphiphile SDS, on the other hand, interacted with BSA in two distinctly different stages, as evidenced from the tensiometric profile. The complexity of the BSA-SDS tensiometric isotherm compared to that of BSA-ATAB arose from the presence of cationic binding sites adjacent to hydrophobic patches of BSA in its native state, so that electrostatic and hydrophobic interactions can cooperatively operate side by side. The interfacial saturation occurred at a lower concentration in the presence of BSA compared to the normal cmc of SDS under identical solution conditions in the absence of BSA, which was slightly delayed for nonionic C12E5. The multitechnique approach evidenced that different experimental techniques probe different physicochemical phenomena and an attempt to show the concurrence of the break points in different techniques is only diluting the essence of this area.

Goitre prevalence, urinary iodine and salt iodisation level in a district of West Bengal, India

OBJECTIVES

We carried out a study to assess the prevalence of goitre, measure urinary iodine excretion (UIE) levels and to estimate salt iodine content at the household level in Howrah district of West Bengal, India.

METHODS

STUDY DESIGN

This is a Cross-sectional descriptive study conducted in September-December 2006.

SETTING

Primary schools located in 30 clusters (villages and wards) randomly selected through 30 cluster sampling methodology.

PARTICIPANTS

2400 school children, aged 8-10 years. Indicators: The indicators used in this study to assess for IDD were recommended by the WHO/UNICEF/ICCIDD. Goitre was assessed clinically by the standard palpation technique. The urinary iodine excretion level was analyzed by the wet digestion method. Salt samples consumed at the household level were collected and tested by the spot iodine testing kit to measure iodine content.

RESULTS

The Total Goitre Rate (TGR) was 13.7% (95% CI = 12.3-15.1%). Grade 1 was 11.4% and Grade 2 (visible goitre) was 2.3%. The TGR was influenced by the age and sex factors but not by religion and residence. The median urinary iodine excretion level was 13 microg/dL (normal range: 10-20 microg/dL) and none had a value less than 5 microg/dL. There was significant negative correlation between UIE levels and the age and place of residence factors. Almost 80% of salt samples tested had adequate iodine content (>or= 15 ppm). Consumption of iodized salts was lower among Hindus and in rural area.

CONCLUSION

In conclusion, the Howrah district is in a transition phase from iodine deficiency to iodine sufficiency.

A mixed-valence octanuclear iron-oxo pyrazolate: assessment of electronic delocalization by structural and spectroscopic analysis

A formally Fe(III)(7)Fe(II) complex, containing an inner Fe(4)O(4)-cubane and four peripheral Fe centers, is derived from the one-electron reduction of its Fe(III)(8) precursor. Spectroscopic analysis of the former reveals that the redox activity of this Fe(8) system is confined within its cubane core. The resulting (Fe(4)O(4))(3+)-cubane, which is valence-delocalized in the NMR, Mössbauer, and IR spectroscopy time scales but valence-trapped in the X-ray photoelectron spectroscopy (XPS) time scale, is better described as a Robin-Day class-II system by the analysis of its near-infrared (NIR) intervalence charge transfer (IVCT) band profile.