25 research outputs found
Studies on Magnetic and Dielectric Properties of Antiferromagnetically Coupled Dinuclear Cu(II) in a One-Dimensional Cu(II) Coordination Polymer
A one-dimensional Cu(II) coordination polymer with encapsulated antiferromagnetically coupled binuclear Cu(II) has been synthesized by using 5-nitroisophthalic acid (5-N-IPA) and 4-aminopyridine (4-APY) [Cu2(5-N-IPA)2(4-APY)4] n (1). Electrical properties are examined by complex impedance (Z*), dielectric permittivity (Ξ΅*), and ac conductivity studies at different frequencies (10 kHz-5 MHz) and temperatures (253-333 K). The contribution of grain and grain boundary has been explained by a different theoretical model. The variable temperature magnetic susceptibility data for compound 1 were recorded between 300 and 2 K. The shape of the curve (ΟM T vs T) indicates dominant antiferromagnetic coupling, which results from the interaction between the copper(II) atoms
In Search of Wound Healing Drugs: A Journey Through Ayurveda
Description of wound healing is a recent concern of modern surgery and medical therapeutics, but first evidences are available in ancient Indian system of medicine, namely Ayurveda in the name of Vrana (wounds) and Vranaropaka (wound healing drugs). It has been reported that in different classical Ayurvedic texts, about 164 medicinal plants, 24 metals and minerals and 18 animal products are described for their wound healing activity. The mechanism of the healing process and the selection of drugs from natural resources are very specific in Ayurveda, and some of these have been scientifically screened. Besides a single component of drug, many classical formulations either in the form of polyherbal or herbo-minerals have been cited in Ayurveda from time to time since pre-vedic era to recent modern time. Many traditional folkloric preparations of India were also later on incorporated in Ayurveda utilizing sources of some pockets of Ayurveda in different parts of the country. Chronological development of these drugs on the basis of physical, molecular and clinical parameters is elaborated vividly with some examples of experimentation like Curcuma longa, Pterocarpus santalinus, Cynodon dactylon and a composed formulation named Kshantak Malam
Carboxylato bridging Cu(II) coordination polymer: Structure, magnetism and catalytic reduction of nitrophenols
The 1D coordination polymer, [Cu 2 ( ΞΌ2 -OH) 2 (DABA) 2 ] n ( 1 ), (HDABA = 4-Diallylamino-benzoic acid) is characterized by Single crystal X-Ray diffraction analysis. The structure switches to a 2D geometry by hy- drogen bonding interactions. Hand grinding aqueous suspension of the coordination polymer, 1 , present in nano regime of av . 100 nm dimension and shows catalytic performance in the reduction of toxic nitro- phenols to corresponding aminophenols by NaBH 4 . The rate constant values ( ΞΊapp ) are 2.4 Γ10 β3 (4-NP), 5.3 Γ10 β3 (2,4-DNP) and 5.6 Γ10 β3 (2,4,6-TNP) s β1 are much higher than reduction by only NaBH 4 . The susceptibility measurements ( ΟM T ) of Cu(II) coordination polymer indicates the presence of a very weak antiferromagnetic coupling between the metal centres. The hand grinding technique and reusability of 1 makes the approach chemically green, cost effective and attracts the attention towards the real-life application
At-Risk and Recent-Onset Type 1 Diabetic Subjects Have Increased Apoptosis in the CD4+CD25+(high) T-Cell Fraction
BACKGROUND: In experimental models, Type 1 diabetes T1D can be prevented by adoptive transfer of CD4+CD25+ FoxP3+ suppressor or regulatory T cells. Recent studies have found a suppression defect of CD4+CD25+(high) T cells in human disease. In this study we measure apoptosis of CD4+CD25+(high) T cells to see if it could contribute to reduced suppressive activity of these cells. METHODS AND FINDINGS: T-cell apoptosis was evaluated in children and adolescent 35 females/40 males subjects comprising recent-onset and long-standing T1D subjects and their first-degree relatives, who are at variable risk to develop T1D. YOPRO1/7AAD and intracellular staining of the active form of caspase 3 were used to evaluate apoptosis. Isolated CD4+CD25+(high) and CD4+CD25β T cells were co-cultured in a suppression assay to assess the function of the former cells. We found that recent-onset T1D subjects show increased apoptosis of CD4+CD25+(high) T cells when compared to both control and long-standing T1D subjects p<0.0001 for both groups. Subjects at high risk for developing T1D 2β3Ab+ve show a similar trend p<0.02 and p<0.01, respectively. On the contrary, in long-standing T1D and T2D subjects, CD4+CD25+(high) T cell apoptosis is at the same level as in control subjects pβ=βNS. Simultaneous intracellular staining of the active form of caspase 3 and FoxP3 confirmed recent-onset FoxP3+ve CD4+CD25+(high) T cells committed to apoptosis at a higher percentage 15.3Β±2.2 compared to FoxP3+ve CD4+CD25+(high) T cells in control subjects 6.1Β±1.7 p<0.002. Compared to control subjects, both recent-onset T1D and high at-risk subjects had significantly decreased function of CD4+CD25+(high) T cells pβ=β0.0007 and pβ=β0.007, respectively. CONCLUSIONS: There is a higher level of ongoing apoptosis in CD4+CD25+(high) T cells in recent-onset T1D subjects and in subjects at high risk for the disease. This high level of CD4+CD25+(high) T-cell apoptosis could be a contributing factor to markedly decreased suppressive potential of these cells in recent-onset T1D subjects
Apoptosis of CD4+CD25high T Cells in Type 1 Diabetes May Be Partially Mediated by IL-2 Deprivation
from T1D subjects. in T1D may be caught up in a relatively deficient cytokine milieu. function in subjects predisposed to T1D
Arylazoimidazole complexes of lead(II)-halide and their photochromism
418-426Lead(II) complexes of 1-alkyl-2-(arylazo)imidazole (Raai-CnH2n+1), [Pb(Raai-CnH2n+1)X2] (X = Cl, Br, I; and Raai-CnH2n+1, R = H, Me and n = 4, 6, 8) have been characterized by UV-vis, IR and 1H-NMR spectroscopy. The coordinated Raai-CnH2n+1 in the complexes undergoes E-to-Z (trans-to-cis) isomerisation about the βN=Nβ group upon being irradiated with UV light in DMF solution. The rate and quantum yields of E-to-Z photoisomerisation (ΟEβZ) of the complexes are poorer than the respective free ligand response and are also affected by the nature of halide present (Cl-, Br- and I-). Variation in physicochemical parameters may be correlated with the effective mass of the photochrome. The rate of isomerisation follows the sequence: [Pb(Raai-CnH2n+1)Cl2] nH2n+1)Br2] nH2n+1)I2]. The Z-to-E isomerisation has been carried out at varying temperatures (298β308 K) to determine the activation energy of Z-to-E (cis-to-trans) isomerisation (Ea: 47.09β63.42 kJ mol-1) and the entropy of activation (S : 166.52 to β109.0 J mol-1 K-1) which is a large negative in the complexes. Theoretical calculation supports cleavage of Pb(II)-N(azo) bond followed by the βN=Nβ rotation in a three-coordinated symmetry rather than the four-coordinated symmetry
The type of responder T-cell has a significant impact in a human in vitro suppression assay.
In type 1 diabetes (T1D), a prototypic autoimmune disease, effector T cells destroy beta cells. Normally, CD4(+)CD25(+high), or natural regulatory T cells (Tregs), counter this assault. In autoimmunity, the failure to suppress CD4(+)CD25(low) T cells is important for disease development. However, both Treg dysfunction and hyperactive responder T-cell proliferation contribute to disease.We investigated human CD4(+)CD25(low) T cells and compared them to CD4(+)CD25(-) T cells in otherwise equivalent in vitro proliferative conditions. We then asked whether these differences in suppression are exacerbated in T1D. In both single and co-culture with Tregs, the CD4(+)CD25(low) T cells divided more rapidly than CD4(+)CD25(-) T cells, which manifests as increased proliferation/reduced suppression. Time-course experiments showed that this difference could be explained by higher IL-2 production from CD4+CD25(low) compared to CD4+CD25- T cells. There was also a significant increase in CD4+CD25(low) T-cell proliferation compared to CD4+CD25- T cells during suppression assays from RO T1D and at-risk subjects (nβ=β28, pβ=β0.015 and pβ=β0.024 respectively).The in vitro dual suppression assays proposed here could highlight the impaired sensitivity of certain responder T cells to the suppressive effect of Tregs in human autoimmune diseases
Clinical Study of 'Triphala' β A Well Known Phytomedicine from India
Triphala' is an age old commonly used Ayurvedic powdered preparation in
Indian systems of medicine. This well known formulation is made by
combining Terminalia chebula, Terminalia belarica and Emblica
officinalis, in equal proportions based on the observation of Ayurvedic
Formulary of India (AFI). The formulation is prescribed in the first
line treatment of many aliments and is used as laxative, detoxifying
agent and rejuvenator. To establish its clinical validity the present
work was undertaken to evaluate its therapeutic potentials and adverse
effects. The Triphala formulation was standardized by HPTLC (High
Performance Thin Layer Chromatography), using Gallic acid as a marker
and was subjected to clinical studies. After proper screening 160
patients of age between 16β52 years were selected for 45 days
clinical study. The effectiveness of trial drugs were judged on the
basis of the subjective and objective parameters. It was observed that
the amount, frequency and consistency of stool were improved in
Triphala treated group. The changes of odor, mucous, flatulence,
belching and abdominal pain where also taken into account. The well
being was assessed on the basis of the parameters like concentration,
appetite, thirst, sleep, hyperacidity in arbitrary scoring system.
Triphala was found to have good laxative property, help in management
of hyperacidity and also improve appetite. No adverse effect was
observed in the treated group when compared to normal patients.
Triphala can be used effectively in the treatment of constipation and
other gastric problems