Study of pulmonary function tests in response to localized cold stimuli in age group between 19-30 years of Guwahati city

Background: The aim of the study was to observe any variation in the pulmonary functions in response to localized cold stimuli in an externally controlled environment.Methods: The baseline pulmonary function parameters were obtained before the introduction of localized cold stimuli. Now the stimuli were introduced by immersing both feet up to ankle in a bucket full of cold water maintained at temperature between 8-10degree Celsius in 30 male healthy subjects (age group 19-30 years) and the parameters were noted after 2 minutes and 5 minutes respectively using a Medspiror (HELIOS) Electronic spirometer and keeping room temperature at 24ocelsius in the Department of Physiology, Gauhati Medical College, Guwahati, Assam, India. For statistical analysis, the value of the pulmonary function parameters were presented as Mean±standard deviation. Analysis of variance (ANOVA) using Statistical Package for Social Sciences (SPSS) version 20 was employed for comparing the parameters and p<0.05 was considered as significant.Results: It was observed that the tidal volume and Inspiratory capacity showed a significant increase (p<0.05) whereas the Inspiratory reserve volume, expiratory reserve volume and forced vital capacity showed a significant decrease (p<0.05) in response to the cold stimuli.Conclusions: A significant effect was obtained in the pulmonary function tests exposed to cold stimuli showing the multidimensional response of the respiratory mechanics to cold, making a base for further information into the cold climatic effect in an individual

Analysis of muscle strength and endurance in healthy young adults and association of muscle strength with muscle endurance

Background: Muscle strength has been studied as a predictor of general health and many diseases.  Data on muscle strength of healthy adults are scarce in Assam. Aim of the study was to describe normative data for hand grip muscle strength and endurance among healthy young males and females of age group 18-21. Also, to find out any correlation between muscles strength and endurance.Methods: We have selected 79 healthy volunteers of both sexes of age group 18-21 years. We have measured muscle strength by hand grip dynamometer. Muscle endurance was calculated by asking the subjects to hold the dynamometer at one third of their muscle strength as long as they can.Results: In this study there were 46 males and 33 females. Mean muscle strength among the males is 27.09(SD7.05) and among the females is 10.76(SD6.19). Similarly mean endurance among males is 41.78(SD31.72) and among females is 16.15(SD9.81). These higher values of muscle strength and endurance in males are statistically significant. We have also found positive correlation between muscle strength and endurance in both the sexes.Conclusions: In this study we have seen that muscle strength and endurance of healthy young males are more than that of females. And also, muscle endurance increases with increase in muscle strength

Neutral tripodal receptors towards efficient trapping of oxalate

Tris(2-aminoethyl)amine (TREN) based pentafluorophenyl urea and 4-cyanophenyl thiourea receptors have shown encapsulation of oxalate (C<SUB>2</SUB>O<SUB>4</SUB><SUP>2−</SUP>) in semi-aqueous environment. A single crystal X-ray study shows trapping of planar conformer of C<SUB>2</SUB>O<SUB>4</SUB><SUP>2−</SUP> in both the cases. Further solution state binding of C<SUB>2</SUB>O<SUB>4</SUB><SUP>2−</SUP> is probed by <SUP>1</SUP>H-NMR titration study in semi-aqueous solvent

Bis-heteroleptic ruthenium(II) complex of a triazole ligand as a selective probe for phosphates

A new bis-heteroleptic ruthenium(II) complex (1) of 2-(1-methyl-1H-1,2,3-triazol-4-yl) pyridine (L) ligand was extensively explored for anion sensing studies. 1[PF<SUB>6</SUB>]<SUB>2</SUB> shows selective sensing of dihydrogen phosphate (H<SUB>2</SUB>PO<SUB>4</SUB><SUP>–</SUP>)/hydrogen pyrophosphate (HP<SUB>2</SUB>O<SUB>7</SUB><SUP>3–</SUP>) among halides, HCO<SUB>3</SUB><SUP>–</SUP>, AcO<SUP>–</SUP>, NO<SUB>3</SUB><SUP>–</SUP>, ClO<SUB>4</SUB><SUP>–</SUP>, HSO<SUB>4</SUB><SUP>–</SUP>, OH<SUP>–</SUP>, BzO<SUP>–</SUP>, H<SUB>2</SUB>PO<SUB>4</SUB><SUP>–</SUP>, and HP<SUB>2</SUB>O<SUB>7</SUB><SUP>3–</SUP> in acetonitrile. Enhancement of emission intensity of 1[PF<SUB>6</SUB>]<SUB>2</SUB> along with a 10 nm red shift of the emission maximum is observed in the presence of H<SUB>2</SUB>PO<SUB>4</SUB><SUP>–</SUP>/HP<SUB>2</SUB>O<SUB>7</SUB><SUP>3–</SUP> selectively. The photoluminescence (PL) titration experiment of 1[PF<SUB>6</SUB>]<SUB>2</SUB> results in binding constants (K<SUB>a</SUB>) of 5.28 × 10<SUP>4</SUP> M<SUP>–1</SUP> and 4.67 × 10<SUP>4</SUP> M<SUP>–1</SUP> for H<SUB>2</SUB>PO<SUB>4</SUB><SUP>–</SUP> and HP<SUB>2</SUB>O<SUB>7</SUB><SUP>3–</SUP>, respectively, which is in good agreement with the K<SUB>a</SUB> values obtained from UV–vis titration experiments (2.97 × 10<SUP>4</SUP> M<SUP>–1</SUP> and 2.45 × 10<SUP>4</SUP> M<SUP>–1</SUP> for H<SUB>2</SUB>PO<SUB>4</SUB><SUP>–</SUP> and HP<SUB>2</SUB>O<SUB>7</SUB><SUP>3–</SUP>, respectively). High selectivity of 1[PF<SUB>6</SUB>]<SUB>2</SUB> toward these two anions in acetonitrile is further confirmed by PL intensity measurement of 1[PF<SUB>6</SUB>]<SUB>2</SUB> upon addition of these two anions in the presence of a large excess of other competitive anions. Further, considerable changes in the lifetime (τ) as well as in the decay pattern of 1[PF<SUB>6</SUB>]<SUB>2</SUB> in the presence of H<SUB>2</SUB>PO<SUB>4</SUB><SUP>–</SUP>/HP<SUB>2</SUB>O<SUB>7</SUB><SUP>3–</SUP> among all tested anions support the selective binding property of 1[PF<SUB>6</SUB>]<SUB>2</SUB> toward these two anions. Significant downfield shift of the triazole −CH proton of 1[PF<SUB>6</SUB>]<SUB>2</SUB> with 1 equiv of H<SUB>2</SUB>PO<SUB>4</SUB><SUP>–</SUP> (Δδ = 0.26 ppm) and HP<SUB>2</SUB>O<SUB>7</SUB><SUP>3–</SUP> (Δδ = 0.23 ppm) in deuterated dimethyl sulfoxide proclaim binding mechanism via C–H···anion interaction in solution state. Finally, single-crystal X-ray structural analysis confirms the first example of dihydrogen pyrophosphate (H<SUB>2</SUB>P<SUB>2</SUB>O<SUB>7</SUB><SUP>2–</SUP>) recognition via solitary C–H···anion interactions

Combined solution-phase, solid-phase and phase-interface anion binding and extraction studies by a simple tripodal thiourea receptor

Tris(2-aminoethyl)amine (tren) based 4-cyanophenyl-substituted tripodal L, tris{[(4-cyanophenyl)amino]ethyl}thiourea receptor, was synthesized and explored thoroughly for anion recognition in solution by NMR spectroscopy and isothermal titration calorimetry (ITC) as well as in the solid state by single-crystal X-ray diffraction studies. Anion recognition properties of L were further exploited toward the extraction of sulfate as well as fluoride from aqueous media using a liquid–liquid extraction technique. A solution-state anion binding study using NMR spectroscopy in [D<SUB>6</SUB>]DMSO and ITC measurements in dry acetonitrile show a relatively higher association constant of L with halides (F<SUP>–</SUP> and Cl<SUP>–</SUP>) over oxyanions (H<SUB>2</SUB>PO<SUB>4</SUB><SUP>–</SUP> and HSO<SUB>4</SUB><SUP>–</SUP>). The single-crystal X-ray structural analysis of complex 1 reveals a monotopic encapsulation of fluoride in L through six N–H···F<SUP>–</SUP> interactions with a distorted trigonal-prismatic geometry, whereas sulfate and carbonate induce dimeric assemblies of L in complexes 2 and 3, respectively. In the case of sulfate, a tight dimeric capsular assembly of ca. 9.5 Å is observed through 15 N–H···O interactions, whereas carbonate forms a sandwich-like dimeric molecular aggregation through 14 N–H···O interactions. In the presence of tetrabutylammonium iodide as the phase transfer agent, L has shown ca. 70 % extraction of fluoride (based on L) and ca. 40 % extraction of sulfate (based on L) from aqueous solutions using an anion-exchange-based liquid–liquid extraction strategy. Extraction of these anions is unambiguously demonstrated by <SUP>1</SUP>H NMR, <SUP>19</SUP>F NMR and FTIR spectroscopy, PXRD and single-crystal X-ray diffraction studies

A Cyanuric Acid Platform Based Tripodal Bis-heteroleptic Ru(II) Complex of Click Generated Ligand for Selective Sensing of Phosphates via C–H···Anion Interaction

A new bis-heteroleptic trinuclear Ru­(II) complex (<b>1</b>[PF₆]₆) has been synthesized from electron deficient cyanuric acid platform based copper-catalyzed azide–alkyne cycloaddition, i.e., CuAAC click generated ligand, 1,3,5-tris [(2-aminoethyl-1H-1,2,3-triazol-4-yl)-pyridine]-1,3,5-triazinane-2,4,6-trione (<b>L1)</b>. Complex <b>1</b>[PF₆]₆ displays weak luminescence (ϕ_f = 0.002) at room temperature with a short lifetime of ∼5 ns in acetonitrile. It shows selective sensing of hydrogen pyrophosphate (HP₂O₇^3–) through 20-fold enhanced emission intensity (ϕ_f = 0.039) with a 15 nm red shift in emission maxima even in the presence of a large excess of various competitive anions like F^–, Cl^–, AcO^–, BzO^–, NO₃^–, HCO₃^–, HSO₄^–, HO^–, and H₂PO₄^– in acetonitrile. Selective change in the decay profile as well as in the lifetime of <b>1</b>[PF₆]₆ in the presence of HP₂O₇^3– (108 ns) further supports its selectivity toward HP₂O₇^3–. UV–vis and photoluminescence titration profiles and corresponding Job’s plot analyses suggest 1:3 host–guest stoichiometric binding between <b>1</b>[PF₆]₆ and HP₂O₇^3–. High emission enhancement of <b>1</b>[PF₆]₆ in the presence of HP₂O₇^3– has resulted in the detection limit of the anion being as low as 0.02 μM. However, <b>1</b>[PF₆]₆ shows selectivity toward higher analogues of phosphates (e.g., ATP, ADP, and AMP) over HP₂O₇^3–/H₂PO₄^– in 10% Tris HCl buffer (10 mM)/acetonitrile medium. Downfield shifting of the triazole C–H in a ¹H NMR titration study confirms that the binding of HP₂O₇^3–/H₂PO₄^– is occurring via C–H···anion interaction. The single crystal X-ray structure of complex <b>1</b> having NO₃^– counteranion, <b>1</b>[NO₃]₆ shows binding of NO₃^– with complex <b>1</b> via C–H···NO₃^– interactions

Bis-Heteroleptic Ruthenium(II) Complex of a Triazole Ligand as a Selective Probe for Phosphates

A new bis-heteroleptic ruthenium­(II) complex (<b>1</b>) of 2-(1-methyl-1<i>H</i>-1,2,3-triazol-4-yl) pyridine (<b>L</b>) ligand was extensively explored for anion sensing studies. <b>1</b>[PF₆]₂ shows selective sensing of dihydrogen phosphate (H₂PO₄^–)/hydrogen pyrophosphate (HP₂O₇^3–) among halides, HCO₃^–, AcO^–, NO₃^–, ClO₄^–, HSO₄^–, OH^–, BzO^–, H₂PO₄^–, and HP₂O₇^3– in acetonitrile. Enhancement of emission intensity of <b>1</b>[PF₆]₂ along with a 10 nm red shift of the emission maximum is observed in the presence of H₂PO₄^–/HP₂O₇^3– selectively. The photoluminescence (PL) titration experiment of <b>1</b>[PF₆]₂ results in binding constants (<i>K</i>_a) of 5.28 × 10⁴ M^–1 and 4.67 × 10⁴ M^–1 for H₂PO₄^– and HP₂O₇^3–, respectively, which is in good agreement with the <i>K</i>_a values obtained from UV–vis titration experiments (2.97 × 10⁴ M^–1 and 2.45 × 10⁴ M^–1 for H₂PO₄^– and HP₂O₇^3–, respectively). High selectivity of <b>1</b>[PF₆]₂ toward these two anions in acetonitrile is further confirmed by PL intensity measurement of <b>1</b>[PF₆]₂ upon addition of these two anions in the presence of a large excess of other competitive anions. Further, considerable changes in the lifetime (τ) as well as in the decay pattern of <b>1</b>[PF₆]₂ in the presence of H₂PO₄^–/HP₂O₇^3– among all tested anions support the selective binding property of <b>1</b>[PF₆]₂ toward these two anions. Significant downfield shift of the triazole −CH proton of <b>1</b>[PF₆]₂ with 1 equiv of H₂PO₄^– (Δδ = 0.26 ppm) and HP₂O₇^3– (Δδ = 0.23 ppm) in deuterated dimethyl sulfoxide proclaim binding mechanism via C–H···anion interaction in solution state. Finally, single-crystal X-ray structural analysis confirms the first example of dihydrogen pyrophosphate (H₂P₂O₇^2–) recognition via solitary C–H···anion interactions