RESUMO
Present work was conducted to study of role of NGAL in diagnosis and staging the severity of diabetic nephropathy in type 2 diabetes mellitus patients to assess serum NGAL, urine albumin levels in diabetic patients with and without apparent nephropathy. MATERIAL: Comparative study conducted in the General Medicine department of SMS Hospital. INCLUSION CRITERIA: Patients of type 2 Diabetes mellitus. EXCLUSION CRITERIA: Patients consuming high protein diet, pregnancy, severe muscular exercises, orthostatic albuminuria, congestive heart failure, urinary tract infections, liver diseases. Patients with type 1 diabetes mellitus. OBSERVATION: The mean age of patient was 51.7 years. Here, HbA1c and NGAL were negatively correlated with each other with Pearson correlation -0.484 (p-value<0.05). In prediabetic patients mean NGAL was 407ng/ml and as HbA1c increases mean NGAL decreases 276.69 ng/ml (P-value <0.0012). As ACR increases mean NGAL increases significantly (P-value<0.05). CONCLUSION: Neutrophil gelatinase-associated lipocalin could be a renal function evaluation marker for patients with renal dysfunction and markers for detection of diabetic nephropathy in patients with type2 diabetes mellitus.
Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Biomarcadores , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Hemoglobinas Glicadas , Humanos , Lipocalina-2/urina , Masculino , Pessoa de Meia-IdadeRESUMO
Anion recognition studies were performed with triazole-appended thiourea conjugates of calix[6]arene (i.e., compound (6) L) by absorption and (1) Hâ NMR spectroscopy by using nineteen different anions. The composition of the species of recognition was derived from ESI mass spectrometry. The absorption spectra of compound (6) L showed a new band at λ=455â nm in the presence of F(-) due to a charge transfer from the anion to the thiourea moiety and the absorbance increases almost linearly in the concentration range 5 to 200â µm. This is associated with a strong visual color change of the solution. Other anions, such as H2 PO4 (-) and HSO4 (-) , exhibit a redshift of the λ=345â nm band and the spectral changes are associated with the formation of an isosbestic point at λ=343â nm. (1) Hâ NMR studies further confirm the binding of F(-) efficiently to the thiourea group among the halides by shifting the thiourea proton signals downfield followed by their disappearance after the addition of more than one equivalent of F(-) . The other anions also showed interactions with compound (6) L, however, their binding strength follows the order F(-) >CO3 (2-) >H2 PO4 (-) ≈CH3 COO(-) >HSO4 (-) . The NMR spectral changes clearly revealed the anion-binding region of the arms in case of all these anions. The anion binding to compound (6) L indeed stabilizes a flattened-cone conformation as deduced based on the calix-aromatic proton signals and was further confirmed by VT (1) Hâ NMR experiments. The stabilization of the flattened-cone conformation was further augmented by the interaction of the butyl moiety of the nBu4 N(+) counterion. The structural features of the anion-bound species were demonstrated by DFT computations and the resultant structures carried the features that were predicted based on the (1) Hâ NMR spectroscopic measurements. In addition, SEM images showed a marigold flower-type morphology for compound (6) L and this has been transformed into a chain-like structure of connected spherical particles in the presence of F(-) . The anion-induced microstructural features are reflective of the binding strength, size, and shape of the anions. The binding strengths of the anions by compound (6) L were further compared with that of compound (4) L, a calix[4]arene analogue of compound (6) L, in order to address the role of the number of arms built on the calixarene platform based on absorption spectroscopy, (1) Hâ NMR spectroscopy, and DFT computations and it was found that compound (6) L is a better receptor for F(-) , which extends its interactions from all the three arms.
RESUMO
A phenylenediamine-capped conjugate of calix[4]arene (Lamino ) was synthesized by reducing its precursor, Limino , with sodium borohydride in methanol. The Lamino sample binds to anions due to the more flexible and bent conformation of the capped aminophenolic binding core, compared to the precursor Limino . The Lamino sample showed selectivity towards H2 PO4 (-) by exhibiting a ratiometric increase in emission by about 11-fold with a detection limit of (1.2±0.2)â µm ((116±20)â ppb) over 15 anions studied, including other phosphates, such as P2 O7 (4-) , adenosine monophosphate (AMP(2-) ), adenosine diphosphate (ADP(2-) ), and adenosine triphosphate (ATP(2-) ). The Lamino sample shows an increase in the absorbance at λ=315â nm in the presence of H2 PO4 (-) , CO3 (2-) , HCO3 (-) , CH3 CO2 (-) , and F(-) . The (1) Hâ NMR spectroscopic titration of Lamino with H2 PO4 (-) , F(-) , and CH3 CO2 (-) showed major changes in the phenylene-capped and salicyl moieties, and thereby, confirming the aminophenolic region as the binding core. However, the binding strength of these anions followed the trend H2 PO4 (-) >F(-) â«CH3 CO2 (-) >HSO4 (-) . The heat changes observed by isothermal titration calorimetry support this trend. The Lamino sample showed reversible sensing towards H2 PO4 (-) and F(-) in the presence of Mg(2+) and Ca(2+) , respectively. NOESY studies of Lamino , in comparison with its anionic complexes, revealed that major conformational changes occurred in the capping region to facilitate the binding of anion. ESI-MS and the Job's method revealed 1:1 stoichiometry between Lamino and H2 PO4 (-) or F(-) . In the SEM micrographs of Lamino , the spherical particles are converted into spherical aggregates and further form large agglomerates and even branched sheets in the presence of anions, depending upon their binding strength.
Assuntos
Calixarenos/química , Fenóis/química , Fenilenodiaminas/química , Difosfato de Adenosina/química , Monofosfato de Adenosina/química , Trifosfato de Adenosina/química , Ânions/química , Boroidretos/química , Calixarenos/síntese química , Calorimetria , Espectroscopia de Ressonância Magnética , Metanol/química , Microscopia Eletrônica de Varredura , Fenóis/síntese química , Fosfatos/química , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
A phenylene diimine capped conjugate of 1,3-calix[4]arene (L) was synthesized and characterized, and its Mg(2+) complex has been isolated and characterized. The chemo sensing ensemble of Mg(2+) bound L provides distinguishable features of response toward phosphates, viz., HPO4(2-), P2O7(4-), and AMP(2-) (Set A) and H2PO4(-), ATP(2-), and ADP(2-) (Set B). While the Set A shows the formation of ternary complex, the Set B does not exhibit any intermediate complex, but both show the release of Mg(2+) and L at different equivalents. The structures of {L + Mg(2+)} and its phosphate bound ternary complexes have been established by computational calculations, and the corresponding results agree well with the experimental ones. The microscopy studies show an aggregation-disaggregation phenomenon in the presence of different equivalents of phosphates in both of the sets. Using the fluorescence data, an INHIBIT logic gate has been built.
Assuntos
Calixarenos/química , Magnésio/química , Microscopia , Modelos Moleculares , Compostos Organometálicos/química , Fenóis/química , Fosfatos/análise , Fosfatos/química , Conformação Molecular , Espectrometria de FluorescênciaRESUMO
A phenylene-diimine-capped conjugate of lower rim 1,3-calix[4]arene (L) was synthesized, characterized, and shown to selectively bind to Mg(2+) using its capped arms. This results in a selective recognition of Mg(2+) through eliciting fluorescence enhancement of â¼70 fold with a detection limit of 40 ± 5 ppb. However, in the presence of blood serum, the lowest detection limit is 209 ± 10 ppb (0.2 µM). The binding of Mg(2+) to L is authenticated by absorption and (1)H NMR data. The Job's plot derived on the basis of the absorption data showed 1:1 stoichiometry between the receptor and Mg(2+). The 1:1 species was further confirmed through ESI MS, that is, being supported by the isotope peak pattern authenticating the presence of Mg(2+) in the complex. The L binds Mg(2+) octahedrally using the tetradentate L(2-) and two additional acetic acid moieties by bringing conformational changes as studied on the basis of MM computations. The conformational changes that occur in the capped arms upon Mg(2+) binding were supported experimentally by NOESY. AFM and SEM studies showed that spherical particles of L are modified into flower and chain type aggregates upon complexation with Mg(2+), confirming the supramolecular behavior of the species formed.
Assuntos
Calixarenos/química , Iminas/química , Iminas/síntese química , Magnésio/química , Fenóis/química , Fenóis/síntese química , Calixarenos/síntese química , Espectroscopia de Ressonância Magnética , Espectrometria de FluorescênciaRESUMO
A new 1,3,5-tris-triazole linked picolylimine conjugate of calix[6]arene (L) has been shown to be selective toward La(3+) by turn on fluorescence with â¼70-fold enhancement and emits blue, with a minimal detection limit of 65 ± 5 ppb (490 nM). The species of recognition has been modeled computationally to have a monocapped twisted square antiprism with a N(6)O(3) binding core about La(3+). The in situ complex of L with La(3+) recognizes F(-) via fluorescence quenching. The reversible response of sensing La(3+) and F(-) sequentially by L has been demonstrated.