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1.
ACS Omega ; 9(1): 456-463, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222515

RESUMO

The textile wastewater sludge (TWS) treatment and disposal are environmentally challenging due to toxic organics and metals. At the same time, cattle manure (CM), with better combustion performance, i.e., calorific value and uniform burning capability, is still underutilized in many parts of the world. This study evaluated and assessed the TWS and CM blending compatibility to convert them into fuel pellets for the direct combustion option and to stabilize toxic contaminants in TWS. After initial drying, grinding, and particle size control of the raw TWS and CM, both were blended at different ratios. The blended and nonblended TWS and CM samples were converted into pellets and analyzed for proximate and ultimate analyses, namely, moisture content, fixed carbon, CHNO, gross calorific value (GCV), bulk density, ash content, and metals, to evaluate the efficacy for energy applications. Out of three blended ratios, i.e., 75:25 (W/W%; CM/TWS), 50:50, and 25:75, the 75:25 blended pellet composition was found appropriate for fuel application. For the 75:25 blend, the obtained GCV was 12.77 MJ/kg, elemental carbon was 27.5%, volatiles were 41.7%, and residue ash was 42.8% of the total weight. Moreover, the blending ratios of 75:25 and 50:50 revealed that elemental and metal (Fe, Cu, Zn, Ni, Cr, Na, Mg, Mn) concentrations in TWS were stabilized to below threshold limits in the obtained residue ash for safe handling. The explored methods of TWS and CM waste processing, blending, and pelletization proposed a new technique for their sustainable waste valorization into energy sources.

2.
Bioorg Med Chem ; 51: 116509, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34798381

RESUMO

A new series of enkephalin-like tetrapeptide analogs modified at the C-terminus by an N-(3,4-dichlorophenyl)-N-(piperidin-4-yl)propionamide (DPP) moiety were designed, synthesized, and tested for their binding affinities at opioid receptors and monoamine transporters to evaluate their potential multifunctional activity for the treatment of chronic pain. Most ligands exhibited high binding affinities in the nanomolar range at the opioid receptors with a slight delta-opioid receptor (DOR) selectivity over mu-opioid receptor (MOR) and kappa-opioid receptor (KOR) and low binding affinities in the micromolar range at the monoamine transporters, SERT and NET. Ligands of which the positions 1 and 4 were substituted by Dmt and Phe(4-X) residues, respectively, showed the excellent binding affinities at three opioid receptors. Among them, Dmt-d-Tic-Gly-Phe(4-F)-DPP was the most promising considering its excellent opioid affinities, particularly unexpected high binding affinity (Ki = 0.13 nM) at the KOR, and moderate interactions with serotonin/norepinephrine reuptake inhibitors (SNRIs). Docking studies revealed that the ligand was a good fit for the KOR binding pocket (binding score = 8,750).


Assuntos
Amidas/farmacologia , Oligopeptídeos/farmacologia , Receptores Opioides kappa/antagonistas & inibidores , Receptores Opioides mu/antagonistas & inibidores , Amidas/química , Relação Dose-Resposta a Droga , Humanos , Ligantes , Modelos Moleculares , Estrutura Molecular , Oligopeptídeos/síntese química , Oligopeptídeos/química , Receptores Opioides kappa/metabolismo , Receptores Opioides mu/metabolismo , Relação Estrutura-Atividade
3.
Pharmaceutics ; 11(11)2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31717566

RESUMO

Raynaud's Phenomenon is a vascular affliction resulting in pain and blanching of the skin caused by excessive and prolonged constriction of arterioles, usually due to cold exposure. Nifedipine is a vasodilatory calcium channel antagonist, which is used orally as the first-line pharmacological treatment to reduce the incidence and severity of attacks when other interventions fail to alleviate the condition and there is danger of tissue injury. Oral administration of nifedipine, however, is associated with systemic adverse effects, and thus topical administration with nifedipine locally to the extremities would be advantageous. However, nifedipine is subject to rapid photodegradation, which is problematic for exposed skin such as the hands. The goal of this project was to analyze the photostability of a novel topical nifedipine cream to UVA light. The effect of incorporating the photoprotectants rutin, quercetin, and/or avobenzone (BMDBM) into the nifedipine cream on the stability of nifedipine to UVA light exposure and the appearance of degradation products of nifedipine was determined. Rutin and quercetin are flavonoids with antioxidant activity. Both have the potential to improve the photostability of nifedipine by a number of mechanisms that either quench the intermolecular electron transfer of the singlet excited dihydropyridine to the nitrobenzene group or by preventing photoexcitation of nifedipine. Rutin at either 0.1% or 0.5% (w/w) did not improve the stability of nifedipine 2% (w/w) in the cream after UVA exposure up to 3 h. Incorporation of quercetin at 0.5% (w/w) did improve nifedipine stability from 40% (no quercetin) to 77% (with quercetin) of original drug concentration after 3 h UVA exposure. A combination of BMDBM and quercetin was the most effective photoprotectant for maintaining nifedipine concentration following up to 8 h UVA exposure.

4.
Pharmaceutics ; 9(4)2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29156634

RESUMO

The focus of this review is to provide an overview of the chitosan based nanoparticles for various non-parenteral applications and also to put a spotlight on current research including sustained release and mucoadhesive chitosan dosage forms. Chitosan is a biodegradable, biocompatible polymer regarded as safe for human dietary use and approved for wound dressing applications. Chitosan has been used as a carrier in polymeric nanoparticles for drug delivery through various routes of administration. Chitosan has chemical functional groups that can be modified to achieve specific goals, making it a polymer with a tremendous range of potential applications. Nanoparticles (NP) prepared with chitosan and chitosan derivatives typically possess a positive surface charge and mucoadhesive properties such that can adhere to mucus membranes and release the drug payload in a sustained release manner. Chitosan-based NP have various applications in non-parenteral drug delivery for the treatment of cancer, gastrointestinal diseases, pulmonary diseases, drug delivery to the brain and ocular infections which will be exemplified in this review. Chitosan shows low toxicity both in vitro and some in vivo models. This review explores recent research on chitosan based NP for non-parenteral drug delivery, chitosan properties, modification, toxicity, pharmacokinetics and preclinical studies.

5.
Eur J Med Chem ; 138: 396-406, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-28688279

RESUMO

A novel series of 5-(aroylhydrazinocarbonyl)escitalopram (58-84) have been designed, synthesized and tested for their inhibitory potential against cholinesterases. 3-Chlorobenzoyl- (71) was found to be the most potent compound of this series having IC50 1.80 ± 0.11 µM for acetylcholinesterase (AChE) inhibition. For the butyrylcholinesterase (BChE) inhibition, 2-bromobenzoyl- (76) was the most active compound of the series with IC50 2.11 ± 0.31 µM. Structure-activity relationship illustrated that mild electron donating groups enhanced enzyme inhibition while electron withdrawing groups reduced the inhibition except o-NO2. However, size and position of the substituents affected enzyme inhibitions. . In docking study of AChE, the ligands 71, 72 and 76 showed the scores of 5874, 5756 and 5666 and ACE of -64.92,-203.25 and -140.29 kcal/mol, respectively. In case of BChE, ligands 71, 76 and 81 depicted high scores 6016, 6150 and 5994 with ACE values -170.91, -256.84 and -235.97 kcal/mol, respectively.


Assuntos
Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Citalopram/análogos & derivados , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Citalopram/síntese química , Citalopram/química , Citalopram/farmacologia , Relação Dose-Resposta a Droga , Electrophorus , Cavalos , Estrutura Molecular , Relação Estrutura-Atividade
6.
Org Lett ; 17(17): 4256-9, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26278016

RESUMO

The preparation of fluoroalkoxy arylboronic esters by iridium-catalyzed aromatic C-H borylation is described. The fluoroalkoxy groups employed include trifluoromethoxy, difluoromethoxy, 1,1,2,2-tetrafluoroethoxy, and 2,2-difluoro-1,3-benzodioxole. The borylation reactions were carried out neat without the use of a glovebox or Schlenk line. The regioselectivities available through the iridium-catalyzed C-H borylation are complementary to those obtained by the electrophilic aromatic substitution reactions of fluoroalkoxy arenes. Fluoroalkoxy arylboronic esters can serve as versatile building blocks.

7.
Bioorg Med Chem ; 23(17): 6014-24, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26189031

RESUMO

A novel serie of escitalopram triazoles (60-88) and a tetrazole (89) have been synthesized and subjected to a study to establish the inhibitory potential of these compounds toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Some selectivity in inhibition has been observed. The 4-chlorophenyl- (75, IC50, 6.71 ± 0.25 µM) and 2-methylphenyl- (70, IC50, 9.52 ± 0.23 µM) escitalopram triazole derivatives depicted high AChE inhibition, while 2-fluorophenyl- (76, IC50 = 4.52 ± 0.17 µM) and 4-fluorophenyl- (78, IC50 = 5.31 ± 0.43 µM) have found to be excellent BChE inhibitors. It has also been observed that ortho, meta and para substituted electron donating groups increase the inhibition, while electron withdrawing groups reduce the inhibition. Docking analyses of inhibitors with AChE have depicted the binding energies for 70 and 75 as ΔG(bind) -6.42 and -6.93 kcal/mol, respectively, while ligands 76 and 78 have shown the binding affinity ΔG(bind) -9.04 and -8.51 kcal/mol, respectively, for BChE.


Assuntos
Citalopram/química , Citalopram/síntese química , Triazóis/química , Triazóis/síntese química , Inibidores da Colinesterase/química , Estrutura Molecular , Relação Estrutura-Atividade
8.
Bioorg Med Chem ; 23(6): 1251-9, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25703306

RESUMO

A series of opioid and serotonin re-uptake inhibitors (SSRIs) bifunctional ligands have been designed, synthesized, and tested for their activities and efficacies at µ-, δ- and κ opioid receptors and SSRIs receptors. Most of the compounds showed high affinities for µ- and δ-opioid receptors and lower affinities for SSRIs and κ opioid receptors. A docking study on the µ-opioid receptor binding pocket has been carried out for ligands 3-11. The ligands 7 and 11 have displayed the highest binding profiles for the µ-opioid receptor binding site with ΔGbind (-12.14kcal/mol) and Ki value (1.0nM), and ΔGbind (-12.41kcal/mol) and Ki value (0.4nM), respectively. Ligand 3 was shown to have the potential of dual acting serotonin/norepinephrine re-uptake inhibitor (SNRI) antidepressant activity in addition to opioid activities, and thus could be used for the design of multifunctional ligands in the area of a novel approach for the treatment of pain and depression.


Assuntos
Desenho de Fármacos , Receptores Opioides/metabolismo , Receptores de Serotonina/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Relação Dose-Resposta a Droga , Humanos , Ligantes , Estrutura Molecular , Inibidores Seletivos de Recaptação de Serotonina/síntese química , Inibidores Seletivos de Recaptação de Serotonina/química , Relação Estrutura-Atividade
9.
Biotechnol Prog ; 30(5): 1221-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25079608

RESUMO

A general mathematical framework has been proposed in this work for scheduling of a multiproduct and multipurpose facility involving manufacturing of biotech products. The specific problem involves several batch operations occurring in multiple units involving fixed processing time, unlimited storage policy, transition times, shared units, and deterministic and fixed data in the given time horizon. The different batch operations are modeled using state-task network representation. Two different mathematical formulations are proposed based on discrete- and continuous-time representations leading to a mixed-integer linear programming model which is solved using General Algebraic Modeling System software. A case study based on a real facility is presented to illustrate the potential and applicability of the proposed models. The continuous-time model required less number of events and has a smaller problem size compared to the discrete-time model.


Assuntos
Reatores Biológicos , Biotecnologia/métodos , Modelos Teóricos , Fluxo de Trabalho
10.
Intern Med J ; 43(1): 96-100, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23324092

RESUMO

Pleural effusion is a common medical condition encountered by doctors. This study was conducted to ascertain the level of junior doctor (physician-in-training) training, knowledge and supervision in the management of pleural effusion. The information was collected with the help of a proforma, from 49 junior medical doctors working in a metropolitan health service. All the doctors who participated in the survey had come across pleural effusion in their practice, but only 67% of doctors had any experience with the procedure of diagnostic thoracentesis. Sixty-seven percent of doctors conveyed that they will refer the majority of cases (75-100%) for radiological-guided thoracentesis. The main reasons for referral for radiologically guided procedure were lack of experience (65%), fear of complications (61%), lack of supervision and guidance (49%), and lack of time (38%). A significant proportion of doctors interviewed (47%) was unaware of the major indications for intercostal tube drainage of parapneumonic effusions. This survey highlights deficiencies in junior doctor knowledge and procedural skills. Junior doctor training should be tailored to increase the 'hands-on' training time and increased patient contact. Senior clinicians should be given sufficient 'protected time' for teaching and training.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Corpo Clínico Hospitalar/educação , Paracentese/educação , Derrame Pleural/diagnóstico , Austrália , Competência Clínica , Pesquisas sobre Atenção à Saúde , Humanos , Medicina , Paracentese/efeitos adversos , Paracentese/estatística & dados numéricos , Derrame Pleural/cirurgia , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde , Estudos de Amostragem , Inquéritos e Questionários
11.
Clin Ophthalmol ; 4: 269-73, 2010 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-20463794

RESUMO

BACKGROUND AND OBJECTIVE: Squint surgery is frequently performed successfully in Hyderabad. However, no study in any detail has been performed on the outcome of monocular surgery for horizontal squint in the region. This study aims to determine the results of monocular surgery for horizontal trabismus. DESIGN: Retrospective/observational study. SUBJECTS AND METHODS: The study was conducted on patients aged under 45 years, presenting with horizontal strabismus and undergoing monocular squint surgery. Anterior segment slit lamp examination, and if possible, posterior segment examination with 90 diopter (D) and 78 D fundoscopes was performed. Angle of deviation was measured. Patients were divided into two groups (esotropia and exotropia). Investigations were performed. Surgery was done under general anesthesia. A second surgical procedure was performed after six months for any residual deviations. RESULTS: After squint surgery, patients in group 1 (79%) and in group 2 (73.3%) had residual deviation of less than 15 prism diopters (PD). The preoperative deviations of 60 PD or less illustrated excellent domino effects with residual deviation of fewer than 15 PD. Three patients with successive deviation underwent a second surgery with excellent outcomes. CONCLUSION: Few extraocular muscles can be prevented due to monocular squint surgery when multiple surgeries are needed.

12.
Met Based Drugs ; 8(3): 137-43, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18475987

RESUMO

Some novel transition metal [Co(II), Cu(II), Ni(II) and Zn(II)] complexes of substituted pyridine Schiff-bases have been prepared and characterized by physical, spectral and analytical data. The synthesized Schiff-bases act as deprotonated tridentate for the complexation reaction with Co(II), Ni(II) and Zn(II) ions. The new compounds, possessing the general formula [M(L)(2)] where [M=Co(II), Cu(II), Ni(II) and Zn(II) and HL=HL(1), HL(2), HL(3) and HL(4)] show an octahedral geometry. In order to evaluate the effect of metal ions upon chelation, the Schiff bases and their complexes have been screened for antibacterial activity against the strains such as Escherichia coli,Staphylococcus aureus, and Pseudomonas aeruginosa. The complexed Schiff bases have shown to be more antibacterial against one more bacterial species as compared to uncomplexed Schiff-bases.

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