Exosome-Mediated Differentiation of Mouse Embryonic Fibroblasts and Exocrine Cells into β-Like Cells and the Identification of Key miRNAs for Differentiation.

Diabetes is a concerning health malady worldwide. Islet or pancreas transplantation is the only long-term treatment available; however, the scarcity of transplantable tissues hampers this approach. Therefore, new cell sources and differentiation approaches are required.

Improved differentiation of human adipose stem cells to insulin-producing β-like cells using PDFGR kinase inhibitor Tyrphostin9.

Diabetes mellitus (DM) is a metabolic syndrome where insulin secretion or the response to insulin produced by the body is compromised. The only available long-term treatment is the transplantation of pancreas or islet for procuring β-cells. However, due to the shortage of β-cell sources from the tissues, differentiation of pluripotent stem cells or terminally differentiated cells into β-cell is proposed as an alternative strategy.

Sensing of Different Human Telomeric G-Quadruplex DNA Topologies by Natural Alkaloid Allocryptopine Using Spectroscopic Techniques.

This article describes how a natural alkaloid allocryptopine (ALL) is able to differentiate two forms of biologically relevant human telomeric (htel22) G-quadruplex DNAs (GQ-DNA) depending on the presence of K and Na ions by steady-state and time-resolved spectroscopic techniques. For both interactions, predominant involvements of static-type quenching mechanism with the negligible influence of dynamic collision are established by UV-vis absorption and fluorescence emission study, which is further supported by fluorescence lifetime measurements. ALL exhibits appreciable affinity toward both GQ-DNAs.

Complete genotyping of unusual species A rotavirus G12P[11] and G10P[14] isolates and evidence of frequent in vivo reassortment among the rotaviruses detected in children with diarrhea in Kolkata, India, during 2014.

Species A rotaviruses (RVA) are the most important cause of acute gastroenteritis in the young of humans and many animal species globally. G1P[8], G2P[4], G3P[8], G4P[8], G9P[6/8] and G12P[6/8] are the predominantly isolated genotypes throughout the world including India. Unusual genotypes from different host species such as G5, G6, G8, G10 and G11 have also been reported in humans with low frequency.

Hospital based surveillance and genetic characterization of rotavirus strains in children (<5 years) with acute gastroenteritis in Kolkata, India, revealed resurgence of G9 and G2 genotypes during 2011-2013.

Introduction: India accounts for an estimated 457,000-884,000 hospitalizations and 2 million outpatient visits for diarrhea. In spite of the huge burden of rotavirus (RV) disease, RV vaccines have not been introduced in national immunization programme of India. Therefore, continuous surveillance for prevalence and monitoring of the circulating genotypes is needed to assess the disease burden prior to introduction of vaccines in this region.

Formation of oligomers in the early phase of pH-induced aggregation of the Alzheimer Aβ(12-28) peptide [corrected].

The early phase in the aggregation process of the Alzheimer's peptide Aβ(12-28) with both protected and unprotected ends was studied by time-resolved infrared spectroscopy and circular dichroism spectroscopy. Aggregation in the time-resolved experiments was initiated by a rapid pH drop caused by the photolysis of 1-(2-nitrophenyl)ethyl sulfate (caged sulfate). The infrared spectra indicate aggregates from both versions of the Aβ(12-28) peptide.

Spectroscopic investigations to reveal the nature of interactions between the haem protein myoglobin and the dye rhodamine 6G.

In the present investigation, steady-state and time-resolved fluorescence with the combination of circular dichroism (CD) spectroscopic techniques were applied to study the interactions of the well-known dye rhodamine 6 G (R6G) with the haem protein human myoglobin (Mb). From the analysis of the results it appears that the static type of fluorescence quenching mechanism is primarily involved, due to ground-state interactions. Although considerable overlapping of fluorescence emission of the dye R6G with the absorption of Mb in the Q-band region exists, the possibility of occurrences of the excitational singlet-singlet non-radiative energy transfer process from R6G to Mb appears to be unlikely, according to time-resolved fluorescence measurements.

Investigations on the photoreactions of phenothiazine and phenoxazine in presence of 9-cyanoanthracene by using steady state and time resolved spectroscopic techniques.

By using electrochemical, steady state and time resolved (fluorescence lifetime and transient absorption) spectroscopic techniques, detailed investigations were made to reveal the mechanisms of charge separation or forward electron transfer reactions within the electron donor phenothiazine (PTZH) or phenoxazine (PXZH) and well known electron acceptor 9-cyanoanthracene (CNA). The transient absorption spectra suggest that the charge separated species formed in the excited singlet state resulted from intermolecular photoinduced electron transfer reactions within the donor PTZH (or PXZH) and CNA acceptor relaxes to the corresponding triplet state. Though alternative mechanisms of via formations of contact neutral radical by H-transfer reaction have been proposed but the observed results obtained from the time resolved measurements indicate that the regeneration of ground state reactants is primarily responsible due to direct recombination of triplet contact ion-pair (CIP) or solvent-separated ion-pair (SSIP).

A detailed spectroscopic study on the interaction of Rhodamine 6G with human hemoglobin.

UV-vis, time-resolved fluorescence and circular dichroism spectroscopic investigations have been made to reveal the nature of the interactions between xanthene dye Rhodamine 6G and the well known protein hemoglobin. From the analysis of the steady-state and time-resolved fluorescence quenching of Rhodamine 6G in aqueous solutions in presence of hemoglobin, it is revealed that the quenching is static in nature. The primary binding pattern between Rhodamine and hemoglobin has been interpreted as combined effect of hydrophobic association and electrostatic interaction.

Fluorescence spectroscopic characterization of the interaction of human adult hemoglobin and two isatins, 1-methylisatin and 1-phenylisatin: a comparative study.

In this report, steady state and time-resolved fluorescence along with circular dichroism (CD) spectroscopic, FTIR, and anisotropy investigations were made to reveal the nature of the interactions between human adult hemoglobin (Hb) and the isatins, 1-methylisatin (1-MI) and 1-phenylisatin (1-PI). From the analysis of the steady state and time-resolved fluorescence quenching of Hb in aqueous solution in the presence of an isatin, i.e.

Does bimolecular charge recombination in highly exergonic electron transfer afford the triplet excited state or the ground state of a photosensitizer?

The investigations were made on photoinduced electron transfer (ET) from the singlet excited state of rubrene (1RU*) to p-benzoquinone derivatives (duroquinone, 2,5-dimethyl-p-benzoquinone, p-benzoquinone, 2,5-dichloro-p-benzoquinone, and p-chloranil) in benzonitrile (PhCN) by using the steady state and time-resolved spectroscopies. The photoinduced ET produces solvent-separated type charge-separated (CS) species and the charge-recombination (CR) process between RU radical cation and semiquinone radical anions obeys second-order kinetics. Not only the CS species but also the triplet excited state of RU (3RU*) is seen in the transient absorption spectra upon laser excitation of a PhCN solution of RU and p-benzoquinone derivatives.

Effects of liquid crystal environment on the spectroscopic and photophysical properties of well-known reacting systems 2,3-dimethylindole (DMI) and 9-cyanoanthracene (9CNA).

Electrochemical and steady-state and time-resolved spectroscopic studies on a disubstituted indole, 2,3-dimethylindole (DMI), and well-known electron acceptor 9-cyanoanthracene (9CNA) in liquid crystal (LC) 4-(n- pentyl)-4'-cyanobiphenyl (5CB) environment demonstrate entirely different spectroscopic and photophysical behaviors from those observed earlier by our research group with the same reacting systems in isotropic media n-heptane and acetonitrile (ACN). From the UV-vis absorption spectral measurements of the donor DMI in the presence of the acceptor 9CNA in liquid crystal medium (in 5CB) in various temperatures above the nematic-isotropic phase transition from 308 to 313 K (pseudo-ordered domain), it was observed that the lower energy lying absorption band of DMI situates in a longer wavelength region than the corresponding band observed in isotropic medium n-heptane or ACN. The possibility of the photochromic effect is discussed.

Photophysical processes involved within the bichromophoric system 9-benzotriazole-1-ylmethyl-9H-carbazole and its role as an artificial photosynthetic device.

From both steady state and fluorescence lifetime measurements it reveals that due to photoexcitation of benzotriazole (BZ) part of the bichromophore, 9(1-H-benzotriazole-lylmethyl)-9H-carbazole (BHC), singlet-singlet energy transfer takes place to populate the lowest excited singlet of carbazole (CZ). CZ, thus being excited indirectly via energy transfer process, undergoes strong charge transfer (CT) reaction with the surrounding polar medium acetonitrile (ACN). On the other hand, very weak CT band was apparent when CZ part, within BHC, was directly excited.