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1.
J Mol Model ; 30(5): 122, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38570356

RESUMEN

CONTEXT: In this study, we have investigated the structure, reactivity, bonding, and electronic transitions of DPA and PDTC along with their Ni-Zn complexes using DFT/TD-DFT methods. The energy gap between the frontier orbitals was computed to understand the reactivity pattern of the ligands and metal complexes. From the energies of FMO's, the global reactivity descriptors such as electron affinity, ionization potential, hardness (η), softness (S), chemical potential (µ), electronegativity (χ), and electrophilicity index (ω) have been calculated. The complexes show a strong NLO properties due to easily polarization as indicated by the narrow HOMO-LUMO gap. The polarizability and hyperpolarizabilities of the complexes indicate that they are good candidates for NLO materials. Molecular electrostatic potential (MEP) maps identified electrophilic and nucleophilic sites on the surfaces of the complexes. TDDFT and NBO analyses provided insights into electronic transitions, bonding, and stabilizing interactions within the studied complexes. DPA and PDTC exhibited larger HOMO-LUMO gaps and more negative electrostatic potentials compared to their metal complexes suggesting the higher reactivity. Ligands (DPA and PDTC) had absorption spectra in the range of 250 nm to 285 nm while their complexes spanned 250 nm to 870 nm. These bands offer valuable information on electronic transitions, charge transfer and optical behavior. This work enhances our understanding of the electronic structure and optical properties of these complexes. METHODS: Gaussian16 program was used for the optimization of all the compounds. B3LYP functional in combination with basis sets, such as LanL2DZ for Zn, Ni and Cu while 6-311G** for other atoms like C, H, O, N, and S was used. Natural bond orbital (NBO) analysis is carried out to find out how the filled orbital of one sub-system interacts with the empty orbital of another sub-system. The ORCA software is used for computing spectral features along with the zeroth order regular approximation method (ZORA) to observe its relativistic effects. TD-DFT study is carried out to calculate the excitation energy by using B3LYP functional.

2.
Chemosphere ; 282: 131135, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34470171

RESUMEN

Hexavalent chromium is a highly toxic element generated due to indiscriminate chromite mining in Sukinda, Odisha. In the present research investigation a relatively higher Cr(VI) resistant (900 mg L-1) bacterium CWB-54 was isolated from the chromite mine water. Based on the biochemical and molecular analysis the strain (CWB-54) was identified as Exiguobacterium mexicanum. When this bacterium was grown at 35 °C, 100 rpm, pH~8.0, and fructose as an electron donor, it could reduce the total hexavalent chromium (100 mg L-1) supplemented in the medium within 33 h of incubation period. Though experiment was carried out to study the effect of Mn, Ni, Cd, Hg and Zn on Cr(VI) reduction by the strain E. mexicanum it has been observed that in the presence of Cd and Hg, Cr(VI) reduction drastically decreased. Characterization of Cr(VI) reduced product by SEM-EDX and TEM analysis revealed intracellular and extracellular Cr(III) deposition in the bacterium, which is assumed to be Cr(OH)3 precipitate in nanometric size. But the extracellular chromate reductase enzyme production is found to be negligible as compared to the intracellular enzyme production. The increased concentration of Cr(VI) above (1000 mg L-1) also showed the genotoxic effect on the DNA. Several reports have been published on Exiguobacterium sp. on different scientific aspect but the current report on the reduction of toxic Cr(VI) by a new species E. mexicanum is a novel one which established the potentiality of this microorganism for a broad area of application.


Asunto(s)
Exiguobacterium , Suelo , Biodegradación Ambiental , Cromo , Oxidación-Reducción
3.
Indian J Nucl Med ; 36(1): 92-94, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34040312

RESUMEN

An elderly male on androgen deprivation therapy for prostatic adenocarcinoma presented with obstructive jaundice. Since biopsy from the head of the pancreas showed neuroendocrine carcinoma (NEC), he was diagnosed with second primary pancreatic NEC. Ga-68 DOTANOC positron emission tomography/computed tomography (PET/CT) done subsequently showed enlarged mildly DOTANOC-avid retroperitoneal nodes infiltrating the pancreas. These nodes were found to be progression of prostate-specific membrane antigen (PSMA) nonavid retroperitoneal nodes visualized in his Ga-68 PSMA PET/CT performed at another institution before 4 months, when there was no lesion in the pancreas. This observation revised the diagnosis from second primary pancreatic NEC to progression of neuroendocrine differentiation in preexisting prostatic adenocarcinoma.

4.
ACS Omega ; 4(25): 21604-21611, 2019 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-31867557

RESUMEN

Effective transportation of fly ash-water slurry through a pipeline from its generation site, a power plant, to a storage site by replacing commercial surfactants such as cetyl trimethyl ammonium bromide and sodium dodecyl sulfate by a natural dispersant extracted from Sapindus laurifolia was studied. The stability of fly ash slurry was determined from its rheological parameters, dispersant concentration, and stabilization mechanism. From surface tensiometric data, the critical micelle concentration of the dispersant was obtained to be 0.017 g/cc. The stabilization of high-concentration fly ash slurry has been studied through its rheological behavior by variation of temperature and dispersant and ash concentration. The rheological result obtained for fly ash concentrations in the range of 50-65% slurry was best justified by the Bingham plastic model. The wettability of fly ash particles is increased in the presence of dispersants, which is inferred from reduction of the surface tension value. The stabilization mechanism of the slurry is explained by a steric factor as indicated by the decrease in the zeta potential value. Air pollution is minimized at its destination site due to agglomeration of fly ash particles, which is confirmed from the SEM microphotograph.

5.
J Environ Manage ; 247: 121-134, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31238200

RESUMEN

A highly lead(II) resistant (up to 2200 mg/l) bacterium PbRPSD202 was selected among 210 lead resistant bacteria isolated from marine environment of Paradeep Port, Odisha for possible biosoption of toxic Pb (II) ions from metals polluted environments. The bacterium was identified as Bacillus xiamenensis following the phenotypic as well as 16S rRNA gene sequence analysis. In addition to Pb(II), it also showed resistance towards other heavy metals like Cd(II), Cr(VI), As(III), Cu(II), Ni(II) and Zn(II). Batch biosorption of Pb(II) using both live and dead biomass of this strain was investigated under different operational parametric conditions such as pH, temperature, NaCl concentration, shaking speed, treatment time, biomass concentration and initial Pb(II) concentration. The maximum Pb(II) uptake of 216.75 and 207.4 mg/g biomass was obtained with live and dead biomass, respectively, at the optimum condition (4% w/v NaCl, pH 6.0, 35 °C, 140 rpm and 1 g/l biosorbent dose). Both active as well as passive Pb(II) bio-sorption process showed best fit with the pseudo-second-order kinetic model. The sorption mechanism was favoured with Langmuir isotherm model indicating monolayer type adsorption. FTIR and FESEM-EDX analysis further ensured the possible interactions of Pb(II) with bacterial cell surface ligands like hydroxyl, carbonyl, carboxyl and amine groups during surface adsorption. TEM analysis revealed the intracellular accumulation of lead ions. This investigation highlights the potential application of this bacterium for bioremediation of lead(II) from the multiple metals contaminated saline environment through biosorption.


Asunto(s)
Bacillus , Adsorción , Biomasa , Concentración de Iones de Hidrógeno , Cinética , Plomo , ARN Ribosómico 16S
6.
Indian J Nucl Med ; 31(2): 134-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27095863

RESUMEN

Carcinoma cervix is the most common gynecological malignancy among Indian women. The common symptoms at presentation include abnormal vaginal bleeding, unusual discharge from the vagina, or pain during coitus and postmenopausal bleeding. Rarely, few patients may present with distant metastases without local symptoms. We present two patients with an unusual presentation of metastatic disease without any gynecological symptoms, where (18)F-flouro deoxy glucose positron emission tomography/computed tomography helped in identifying the primary malignancy in the uterine cervix.

7.
J Clin Oncol ; 34(11): 1197-207, 2016 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-26858335

RESUMEN

PURPOSE: An open-label, noninferiority study to evaluate the impact of epoetin alfa (EPO) on tumor outcomes when used to treat anemia in patients receiving chemotherapy for metastatic breast cancer. METHODS: Women with hemoglobin ≤ 11.0 g/dL, receiving first- or second-line chemotherapy for metastatic breast cancer, were randomly assigned to EPO 40,000 IU subcutaneously once a week or best standard of care. The primary end point was progression-free survival (PFS). Secondary end points included overall survival, time to tumor progression, overall response rate, RBC transfusions, and thrombotic vascular events. RESULTS: In 2,098 patients randomly assigned, median PFS (based on investigator-determined disease progression [PD]) was 7.4 months in both groups (hazard ratio [HR], 1.089; 95% CI, 0.988 to 1.200); upper bound exceeded prespecified noninferiority margin of 1.15. Median PFS per independent review committee-determined PD was 7.6 months in both groups (HR, 1.028; 95% CI, 0.922 to 1.146); upper bound did not exceed prespecified noninferiority margin. Median overall survival at clinical cutoff (1,337 deaths) was 17.2 months in the EPO and 17.4 months in the best standard of care group (HR, 1.057; 95% CI, 0.949 to 1.177), median time to tumor progression was 7.5 months in both groups (HR, 1.094; 95% CI, 0.991 to 1.209), and overall response rate was 50% versus 51% (odds ratio, 0.950; 95% CI, 0.799 to 1.130). RBC transfusions were 5.8% versus 11.4% (P < .001), and thrombotic vascular events were 2.8% versus 1.4% (P = .038), respectively. CONCLUSION: The primary end point, PFS based on investigator-determined PD, did not meet noninferiority criteria. As a consistency assessment with the primary finding, PFS based on independent review committee-determined PD met noninferiority criteria. Overall, this study did not achieve noninferiority objective in ruling out a 15% increased risk in PD/death. RBC transfusion should be the preferred approach for the management of anemia in this population.


Asunto(s)
Anemia/prevención & control , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Epoetina alfa/uso terapéutico , Hematínicos/uso terapéutico , Adulto , Anciano , Anemia/inducido químicamente , Anemia/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/mortalidad , Progresión de la Enfermedad , Esquema de Medicación , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Oportunidad Relativa , Calidad de Vida , Nivel de Atención , Resultado del Tratamiento
8.
Indian J Nucl Med ; 31(1): 55-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26917898

RESUMEN

Anaplastic large cell lymphoma (ALCL) is a rare type of nonHodgkin's lymphoma (NHL), but one of the most common subtypes of T-cell lymphoma. It is an aggressive T-cell lymphoma, and some ALCL may mimic less aggressive classical HL histopathlogically. It may be misdiagnosed unless careful immunohistochemical examination is performed. As the prognosis and management of these two lymphomas vary significantly, it is important to make a correct diagnosis. We describe a case who was diagnosed as classical HL by histopathological examination of cervical lymph node, in whom (18)F-flouro deoxyglucose positron emission tomography/computed tomography appearances were unusual for HL and warranted review of histopathology that revealed anaplastic lymphoma kinase-1 negative anaplastic large T-cell lymphoma, Hodgkin-like variant, thereby changing the management.

9.
Indian J Dermatol ; 60(2): 176-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25814707

RESUMEN

Cutaneous B cell lymphomas can arise primarily from the skin or may occur due to secondary spread from nodal lymphomas. Primary lymphomas are confined to the skin without systemic spread and they differ from secondary lymphomas in their clinical behavior, treatment and prognosis. Cutaneous lymphomas being relatively rare, lack of precise definition and understanding of their clinical behavior diseases leads to pitfalls in the diagnosis. We report two cases of cutaneous B cell lymphomas who presented with fever of unknown origin initially and later found to have skin lesions. Hence, skin can be a potential diagnostic clue in the evaluation of patients with fever of unknown origin. The distinctions between the primary and the secondary lymphomas become important in choosing the treatment and assessing the prognosis.

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