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1.
J Assoc Physicians India ; 70(4): 11-12, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35443326

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-Idade
2.
Chemistry ; 22(26): 8903-14, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27167164

RESUMO

Anion recognition studies were performed with triazole-appended thiourea conjugates of calix[6]arene (i.e., compound (6) L) by absorption and (1) H 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=455 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 200 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=345 nm band and the spectral changes are associated with the formation of an isosbestic point at λ=343 nm. (1) H 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) H 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) H 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) H 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.

3.
Chemistry ; 22(26): 8980-9, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27218408

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) µm ((116±20) 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=315 nm in the presence of H2 PO4 (-) , CO3 (2-) , HCO3 (-) , CH3 CO2 (-) , and F(-) . The (1) H 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(-) ≫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 Electrospray
4.
Anal Chem ; 87(18): 9344-51, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26301897

RESUMO

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 Fluorescência
5.
J Org Chem ; 79(12): 5763-70, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24874120

RESUMO

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 ∼70 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 Fluorescência
6.
Org Lett ; 14(12): 2968-71, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22676137

RESUMO

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 ∼70-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.


Assuntos
Calixarenos/química , Corantes Fluorescentes/química , Flúor/química , Iminas/química , Lantânio/química , Fenóis/química , Triazóis/química , Corantes Fluorescentes/análise , Flúor/análise , Íons/química , Lantânio/análise , Modelos Moleculares , Estrutura Molecular
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