Efficacy and safety of ultrasound cycloplasty in Indian eyes with open-angle glaucoma.

Purpose: To evaluate the safety and efficacy of ultrasound cycloplasty in eyes with primary or secondary open-angle glaucoma, not amenable to adequate control of intra-ocular pressure (IOP) with medical treatment. Methods: Prospective interventional cohort study of 28 eyes of 28 subjects in a tertiary eye care centre in India in patients with open-angle glaucoma. All enrolled eyes underwent ultrasound cycloplasty with the second-generation probe with six shots of 8 s each, operated by a single surgeon between November 2018 and January 2020. They were followed up for a period of 12 months. The primary treatment outcome was IOP and the secondary outcomes were vision and postoperative complications. Results: A total of 28 eyes of 28 patients were studied, and the mean age was 63.82 ± 6.46 years. Primary open-angle glaucoma (75%) was the most common etiology. There was significant reduction in IOP from the baseline (24.93 ± 4.27 mmHg) to the postoperative value (15.82 ± 3.14 mmHg) at the end of 12 months (P < 0.00001). Mean reduction in IOP was 9.14 ± 4.09 mmHg at 12 months (36.66%). Number of ocular hypotensives reduced significantly from baseline (3.32 ± 0.47) to 12-month postoperative follow-up (0.68 ± 0.74) (P < 0.00001). Qualified success was achieved in 89.28% eyes. No major complications were noted. Conclusion: Ultrasound cycloplasty is found to be effective and safe in eyes with open-angle glaucoma because of the primary or secondary etiology, being more effective in the former.

The complete mitochondrial genome study and phylogenetic analysis of Asiatic Water Snake (Fowlea piscator) using 'Next-Generation Sequencing' technology.

The first complete mitochondrial genome sequencing of Asiatic Water snake or Checkered Keelback or Fowlea piscator (=Xenochrophis piscator) was carried out using Next-Generation Sequencing technology. The complete mitochondrial genome of Asiatic Water snake is 16,999bp long with a base composition of 33% A, 28% T, 12% G and 27% C, with a GC content of 39%. Like the typical snake mitochondrial genome, F. piscator also shows relatively similar mitogenome arrangement comprising 37 genes including 13 protein-coding genes, 22 tRNA genes, two rRNA genes and two non-coding regions or a duplicated control region (D-Loop) along with an origin of replication. Nine genes including eight tRNAs and NAD6 were encoded on the Light or L-strand. Phylogenetic analyses using the complete mitochondrial genome of F. piscator demonstrate a close relationship with the family Colubridae and sub family Natricinae.

Anticancer activity and cell death mechanism of Pt(II) complexes: Their in vitro bio-transformation to Pt(II)-DNA adduct formation and BSA binding study by spectroscopic method.

Pt(II) complex cis-[Pt(PEA)(OH2)2] X2, C-2 (where, PEA = 2-Pyridylethylamine and X  = ClO4- or NO3-) was synthesized by hydrolysis of cis-[Pt(PEA)Cl2] C-1. Glutathione (GSH) and DL-penicilamine (DL-pen) substituted complexes cis-[Pt(PEA)(GSH)],C-3 and cis-[Pt(PEA)DL-pen)]X C-4 were synthesized and characterized by spectroscopic methods. Kinetic studies were traced on complex C-2 with the thiols, GSH and DL-pen. Pt(II)-Sulfur adduct formation mechanisms of the substituted products C-3 and C-4 were established from the kinetic investigation. At pH 4.0, C-2 - thiols interactions follow two consecutive steps: the first step is dependent, and the second is independent of [thiol]. The association equilibrium constant (KE), substitution rate constants for both steps (k1 & k2), and activation parameters (ΔH‡ and ΔS‡) have been assessed to propose the mechanism. Agarose gel electrophoresis mobilization pattern of DNA with complexes was performed to visualize the interaction nature. CT-DNA and BSA binding activities of the complexes have been executed by electronic, fluorescence spectroscopy, and viscometric titration methods. Evaluation of thermodynamic parameters (ΔH0, ΔS0, and ΔG0) from BSA binding constants was executed to propose the driving forces of interaction between these species. A molecular docking study was performed to evaluate the binding mode of complexes with BDNA strands. Anticancer activity of the complexes C-1 to C-4 was explored on both A549 and HEp-2 cell lines, compared with approved anticancer drugs cisplatin, carboplatin, and oxaliplatin. All these complexes were tested by NBT assay on normal cell line skeletal muscle cells (L6 myotubes) to observe the adverse effects compared to recognized anticancer medications. The ultimate aim is to explore the role of anticancer agents on cell death mechanism, which has been performed by flow-cytometer on HEp-2 cell lines.

Contrasting spectroscopic response of human hemoglobin in presence of graphene oxides and its reduced form: Comparative approach with carbon quantum dots.

Recently, a considerable amount of research is being directed towards study of graphene oxide (GO) and its reduced form (RGO) since their exposed functional groups make them better candidates in nanobiotechnolgy. In order to assess their biocompatibility, the nature of interactions between Human Hemoglobin (HHb) and GO/RGO are monitored since a comparative spectroscopic approach towards understanding their nature of interactions has not been investigated previously. UV-vis spectroscopy reveals hyperchromicity for HHb-GO system and hypochromicity for HHb-RGO system in the region of absorption of tryptophan/tyrosine residues. Notably, although steady-state fluorescence static quenching of HHb for GO and enhancement of fluorescence for RGO is noticed, but average fluorescence-lifetime is remaining unchanged in presence of GO/RGO. Calorimetric data illustrates three-site and five-site binding model to be the best-fit model for GO and RGO respectively. Also, synchronous fluorescence quenching corresponding to alterations in microenvironment of tryptophan/ tyrosine residues is observed only in presence of GO. Likewise FTIR spectroscopy elucidates involvement of both amide I and amide II bond of HHb backbone through H-bonding interaction only for GO. Furthermore RLS spectra demonstrate an increase and a decrease in signal for GO and RGO respectively. Surprisingly, secondary structure of HHb is maintained upon interaction with both GO/RGO, as revealed by CD spectroscopy, thus supporting their potential application in biological microenvironment. Thus it appears that the spectroscopic properties of HHb upon interaction with GO is altered upon its reduction to RGO. Furthermore the role of HHb as good candidate for bimolecular interaction has been highlighted.

Fluorescence enhancement via aggregation effect due to microenvironmental alterations in human hemoglobin protein in presence of carbon quantum dots (CQD): Comparative spectroscopic approach.

CQDs have emerged with outstanding properties as a star member of carbon nanomaterial family and in order to reveal its wide-range of application in biological microenvironment the interactions between human hemoglobin (HHb) and CQD and also with ethylenediamine-functionalized CQD (NCQD) are assessed using several techniques. Firstly, UV-vis absorption spectra of HHb reveal hyperchromic effect in the region of absorbance of tryptophan and tyrosine residues and also hypochromicity of Soret band in presence of CQD and NCQD. Interestingly, steady-state fluorescence spectroscopy reveal distinct fluorescence enhancement of HHb with significant red shift thereby indicating exposures of tryptophan and tyrosine residues to a more hydrophilic environment. However synchronous fluorescence spectra reveal that the microenvironment of tryptophan and tyrosine residues is altered in opposite manner, i.e. exposure of tryptophan residues to a more hydrophilic environment and the tyrosine residues to a more hydrophobic environment. Moreover the fluorescence enhancement is observed to be accompanied by increase in average fluorescence-lifetime and decrease in steady-state anisotropy thus signifying a decrease in restriction of rotational motion. Furthermore tryptophan residues within HHb appear to interact more with CQD compared to NCQD. Thermodynamic parameters as revealed by Isothermal Titration Calorimetry (ITC) demonstrate that electrostatic, hydrogen bonding and hydrophobic interactions are the predominant modes of interactions in presence of CQD. Whereas hydrophobic and hydrogen bonding interactions are the major interacting forces in presence of NCQD with five-site sequential binding as best-fit model in both the cases. Such interactions also appear to be associated with an increase in aggregation of HHb as evident from the measurements by atomic force microscopy (AFM) and dynamic light scattering (DLS) study. Although FT-IR spectra display alteration of amide I band, but the overall secondary structure of HHb seems to be nearly retained even in presence of CQDs, as evident in the CD spectra. These observations thus highlight the potential biomedical application of CQDs in biological microenvironment of human especially as drug-delivery system. Also bimolecular interaction of HHb as a model protein with other nanoparticles at the nano bio-interface has been outlined.

To reveal the nature of interactions of human hemoglobin with gold nanoparticles having two different morphologies (sphere and star-shaped) by using various spectroscopic techniques.

The nature of interactions between heme protein human hemoglobin (HHb) and gold nanoparticles of two different morphologies that is GNP (spherical) and GNS (star-shaped) have been investigated by using UV-vis absorption, steady state fluorescence, synchronous fluorescence, resonance light scattering (RLS), time resolved fluorescence, FT-IR, and circular dichroism (CD) techniques under physiological condition of pH ~7 at ambient and different temperatures. Analysis of the steady state fluorescence quenching of HHb in aqueous solution in the presence of GNP and GNS suggests that the nature of the quenching is of static type. The static nature of the quenching is also confirmed from time resolved data. The static type of quenching also indicates the possibility of formation of ground state complex for both HHb-GNP and HHb-GNS systems. From the measurements of Stern-Volmer (SV) constants KSV and binding constants, KA and number of binding sites it appears that HHb forms stronger binding with GNP relative to GNS. Analysis of the thermodynamic parameters indicates that the formation of HHb-GNP and HHb-GNS complexes are spontaneous molecular interaction processes (∆G<0). In both cases hydrogen bonding and van der Waals interactions play a dominant role (∆H<0, ∆S<0). Synchronous fluorescence spectroscopy further reveals that the ground state complex formations of HHb-GNP and HHb-GNS preferably occur by binding with the amino acid tyrosine through hydrogen bonding interactions. Moreover the α-helicity contents of the proteins as obtained from the circular dichroism (CD) spectra appears to be marginally reduced by increasing concentrations of GNP and GNS and the α-helical structures of HHb retain its identity as native secondary structure in spite of complex formations with GNP or GNS. These findings demonstrate the efficiency of biomedical applications of GNP and GNS nanoparticles as well as in elucidating their mechanisms of action as drugs or drug delivery systems in human.