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1.
ACS Omega ; 9(16): 17706-17725, 2024 Apr 23.
Article En | MEDLINE | ID: mdl-38680368

Herein, this study was compiled to investigate a suitable solution for the fabrication and development of the multifunctional defense tent from previously reported research. The military always needs to protect their soldiers and equipment from detection. The advancement of infrared detection technology emphasizes the significance of infrared camouflage materials, reducing thermal emissions for various applications. Objects emit infrared radiation detectable by devices, making military targets easily identifiable. Infrared camouflage mitigates detection by lowering an object's infrared radiation, achieved by methods such as reducing surface temperature, which is crucial in designing military tents with infrared (IR) camouflage, considering water repellency and antibacterial features. Water repellency, as well as antimicrobial properties, in army tents is also important as they have to survive in different situations. All these problems should be addressed with the required properties; therefore, the authors try to introduce a new method from which multifunctional tents can be produced through economical, multifunctional, and sustainable materials that have IR protection, water repellency, ultraviolet (UV) protection, air filtration and permeability, and antimicrobial properties. There is still no tent that performs multiple functions at a time, even those functions that do not correlate with each other such as water repellency, IR protection, antimicrobial, and air permeability. So, a multifunctional tent could be the solution to all these problems having all the properties discussed above. In this study based on the literature review, authors concluded a method for the required tent for canvas fabric coated with zinc sulfide (ZnS), graphene oxide (GO), and zinc oxide (ZnO), or these materials should be incorporated in fiber formation because fiber composition has more impact. These multifunctional tents will be very beneficial due to their multifunctions like weather resistance, durability, and long life. These would help the army in their missions by concealing their soldiers and equipment from detection by cameras and providing filtered air inside the tent in case of gases or explosions. The proposed method will help to fulfill the stated and implied needs of customers.

2.
Microsc Res Tech ; 87(1): 31-41, 2024 Jan.
Article En | MEDLINE | ID: mdl-37909383

Three new species Buellia darelensis, B. densitheca, B. kashmirensis and two new records B. elegans and B. taishanensis are added to the lichen biota of Pakistan. Buellia darelensis and B. kashmirensis share the same habitats found on the rock while B. densitheca colonized on bark of Pinus hardwoods in the Himalayan forest, Pakistan. Morphological, chemical, and phylogenetic analyses were carried out to elucidate the placement of these species and to support the delimitation of the new taxa. Detailed descriptions and figures for the species are given, and a key to all known buellioid species from Pakistan is provided. RESEARCH HIGHLIGHTS: During recent explorations of lichens from different regions of Pakistan, we observed specimens that could not be readily assigned to any known species. A phylogenetic analysis of the internal transcribed spacer nrDNA region confirms their position within the genus Buellia, and morphological data showed distinctiveness of three species from other known species of the genus. We therefore describe these specimens as new species to science, and two species are as new records for the country. Pakistan exhibits a large altitudinal variation, with climatic conditions and a diverse vegetation that supports a diverse and conspicuous lichen biota. The nature reserves have abundant biological resources, and it is expected that more new species of lichen may be discovered in the future.


Ascomycota , DNA Barcoding, Taxonomic , Phylogeny , DNA Barcoding, Taxonomic/methods , Sequence Analysis, DNA , Pakistan , DNA, Fungal/genetics , Ascomycota/genetics , Microscopy, Electron
3.
Bioorg Chem ; 80: 99-111, 2018 10.
Article En | MEDLINE | ID: mdl-29894893

Thymidine phosphorylase (TP) is an angiogenic enzyme. It plays an important role in angiogenesis, tumour growth, invasion and metastasis. In current research work, we study the effect of structural modification of dihydropyrimidine-2-ones (DHPM-2-ones) on TP inhibition. A series of eighteen new derivatives of 3,4-dihydropyrimidone-2-one were designed and synthesized through the structural modification at C-6 position. All these new derivatives were then assessed for in-vitro inhibition of thymidine phosphorylase (TP) from E. coli. Oxadiazole derivatives 4a-e exhibited excellent TP-inhibition at low micromolar concentration levels better than standard drug 7-deazaxanthine (7-DX). Among all these compounds, 4b was found to be the most potent with IC50 = 1.09 ±â€¯0.004 µM. Anti-angiogenesis potential of representative compounds were also studied in a chorioallantoic membrane (CAM) assay. Here again, compound 4b was found to be the potent anti-angiogenesis compound in a CAM assay. Docking studies were also performed with Molecular Operating Environment (MOE) to further analyse the mode of inhibition of these compounds. Binding mode analysis of the most active inhibitors showed that these are well accommodated into the binding site of enzyme though stable hydrogen bonding and hydrophobic interactions.


Angiogenesis Inhibitors/chemical synthesis , Drug Design , Enzyme Inhibitors/chemical synthesis , Escherichia coli Proteins/metabolism , Pyrimidines/chemistry , Thymidine Phosphorylase/metabolism , Angiogenesis Inhibitors/metabolism , Angiogenesis Inhibitors/pharmacology , Animals , Binding Sites , Catalytic Domain , Chickens , Enzyme Inhibitors/metabolism , Enzyme Inhibitors/pharmacology , Escherichia coli/enzymology , Escherichia coli Proteins/antagonists & inhibitors , Inhibitory Concentration 50 , Molecular Docking Simulation , Neovascularization, Physiologic/drug effects , Pyrimidines/metabolism , Pyrimidines/pharmacology , Structure-Activity Relationship , Thymidine Phosphorylase/antagonists & inhibitors
4.
Eur J Med Chem ; 145: 140-153, 2018 Feb 10.
Article En | MEDLINE | ID: mdl-29324337

Present work describes the in vitro antibacterial evaluation of some new amino acid conjugated antimicrobial drugs. Structural modification was attempted on the three existing antimicrobial pharmaceuticals namely trimethoprim, metronidazole, isoniazid. Twenty one compounds from seven series of conjugates of these drugs were synthesized by coupling with some selected Boc-protected amino acids. The effect of structural features and lipophilicity on the antibacterial activity was investigated. The synthesized compounds were evaluated against five standard American type culture collection (ATCC) i.e. Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi strains of bacteria. Our results identified a close relationship between the lipophilicity and the activity. Triazine skeleton proved beneficial for the increase in hydrophobicity and potency. Compounds with greater hydrophobicity have shown excellent activities against Gram-negative strains of bacteria than Gram-positive. 4-amino unsubstituted trimethoprim-triazine derivative 7b have shown superior activity with MIC = 3.4 µM (2 µg/mL) for S. aureus and 1.1 µM (0.66 µg/mL) for E. coli. The synthesized compounds were also evaluated for their urease inhibition study. Microbial urease from Bacillus pasteurii was chosen for this study. Triazine derivative 7a showed excellent inhibition with IC50 = 6.23 ±â€¯0.09 µM. Docking studies on the crystal structure of B. pasteurii urease (PDB ID 4UBP) were carried out.


Amino Acids/pharmacology , Anti-Bacterial Agents/pharmacology , Enzyme Inhibitors/pharmacology , Isoniazid/pharmacology , Metronidazole/pharmacology , Trimethoprim/pharmacology , Amino Acids/chemistry , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Bacillus/drug effects , Bacillus/enzymology , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Escherichia coli/drug effects , Hydrophobic and Hydrophilic Interactions , Isoniazid/chemical synthesis , Isoniazid/chemistry , Metronidazole/chemical synthesis , Metronidazole/chemistry , Microbial Sensitivity Tests , Molecular Structure , Pseudomonas aeruginosa/drug effects , Salmonella typhi/drug effects , Staphylococcus aureus/drug effects , Structure-Activity Relationship , Trimethoprim/chemical synthesis , Trimethoprim/chemistry , Urease/antagonists & inhibitors , Urease/metabolism
5.
J Pak Med Assoc ; 67(12): 1956-1958, 2017 Dec.
Article En | MEDLINE | ID: mdl-29256556

Parathyroid carcinoma is a rare malignant neoplasm of the parathyroid glands which results in enlargement and excessive production of parathyroid hormone (PTH) responsible for pathologically raising calcium levels in the blood resulting in bone pain/fractures, renal stones and other signs of hypercalcaemia. A 37 year old woman presented with sudden, spontaneous bone pain and fracture of the right femoral shaft. This unusual presentation was explained by extremely high PTH levels and hypercalcaemia in the blood and a hard, solitary mass palpable in the neck. During surgical excision of this mass, finding of several adhesions, possible capsular invasion and lymph node enlargement led to a diagnosis of parathyroid carcinoma. The neoplasm proliferates via adenoma-carcinoma sequence so early diagnosis and prompt surgical excision with post-operative care may provide palliation and keep recurrences in check. Pancreas and pituitary evaluation is also necessary as this presentation may be a part of Wermer (MEN-1) syndrome. .


Femoral Fractures , Parathyroid Neoplasms , Adult , Female , Femoral Fractures/diagnostic imaging , Femoral Fractures/etiology , Femoral Fractures/surgery , Humans , Parathyroid Neoplasms/complications , Parathyroid Neoplasms/diagnosis
6.
Bioorg Chem ; 74: 53-65, 2017 10.
Article En | MEDLINE | ID: mdl-28753459

In our previous report, we have identified 3,4-dihydropyrimidine scaffold as promising class of urease inhibitor in a structure based virtual screen (SBVS) experiment. In present study, we attempted to optimize the scaffold by varying C-5 substituent. The elongation of the C-5 chain was achieved by the reaction of C-5 ester with hydrazine leading to C-5 carbohydrazides which were further used as building blocks for the synthesis of fifteen new compounds having diverse moieties. A significantly higher in vitro urease inhibitory activity with IC50 values in submicromolar range was observed for semithiocarbazide derivatives (4a-c, 0.58-0.79µM) and isatin Schiff base derivative 5a (0.23µM). Docking analysis suggests that the synthesized compounds were anchored well in the catalytic site and extending to the entrance of binding pocket and thus restrict the mobility of the flap by interacting with its key amino acid residues. The overall results of urease inhibition have shown that these compounds can be further optimized and developed as lead urease inhibitors.


Canavalia/enzymology , Drug Design , Enzyme Inhibitors/pharmacology , Molecular Docking Simulation , Pyrimidines/pharmacology , Urease/antagonists & inhibitors , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Molecular Structure , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Quantum Theory , Structure-Activity Relationship , Urease/metabolism
7.
J Pak Med Assoc ; 67(6): 968, 2017 Jun.
Article En | MEDLINE | ID: mdl-28585611

A cross sectional study was conducted in Services Hospital, Lahore using a self administered questionnaire to test the knowledge, attitude and prescribing practices of residents and attending physicians using non-probability convenience sampling. A total of 116 questionnaires were filled (Response rate=77.3%). Knowledge was below average (mean score of 3.66±1.1). Only 18 physicians (16%) could correctly estimate the rates of resistance of Klebsiella pneumoniae and pseudomonas aeruginosa to cephalosporin. Mostly physicians reviewed their decisions to prescribe an antibiotic by discussing with a senior colleague (n=93; 80%). When they did, the senior colleague sometimes recommended a different antibiotic (n=106; 91%). Seventy seven physicians (66%) reported that they prescribed more than one antibiotic per day. Physicians also stated that their decision of antimicrobial prescription was influenced by patient's socioeconomic status (n=108; 93.1%) and patients' demands (n=24; 20.7%). This study highlighted the importance of Antimicrobial stewardship and revealed topics to address during future antimicrobial prescribing interventions such as dissemination of information about local resistance rates and encouraging knowledge about antimicrobials.


Antimicrobial Stewardship , Attitude of Health Personnel , Clinical Competence , Drug Resistance, Microbial , Physicians , Practice Patterns, Physicians' , Clinical Decision-Making , Cross-Sectional Studies , Humans , Pakistan , Patient Preference , Social Class
8.
Bioorg Chem ; 69: 91-101, 2016 12.
Article En | MEDLINE | ID: mdl-27750058

Based on the pharmacological importance of dihydropyrimidine (DHPM) scaffold, substituted DHPMs linked with acetamide linker to substituted aromatic anilines were synthesized and evaluated for their potency as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors. The good AChE inhibitory activity of 4-dihydropyrimidine-2-thione (4a-h) and 2-amino-1,4-dihyropyrimidines (5a-h) series was observed with compound 4a and 4d identified as the most potent compounds with IC50 values of 0.17±0.01 and 0.39±0.04µMrespectively. The inhibition of BChE was found in a broader range of concentrations (2.37-56.32µM). To explore the binding insights into the enzyme, molecular docking study was carried out using GOLD software. The binding mode analysis indicated that all of these inhibitors are well accommodated in the active site and interact with the key amino acid residues of Catalytic anionic site (CAS) and peripheral anionic site (PAS). Furthermore, in silico ADMET predictions suggest that these compounds are non-AMES toxic with good blood brain barrier (BBB) penetration, human intestinal absorption.


Acetylcholinesterase/metabolism , Cholinesterase Inhibitors/pharmacology , Drug Design , Pyrimidines/pharmacology , Absorption, Physiological , Binding Sites/drug effects , Blood-Brain Barrier/drug effects , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Dose-Response Relationship, Drug , Humans , Intestinal Mucosa/metabolism , Intestines/drug effects , Molecular Docking Simulation , Molecular Structure , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Structure-Activity Relationship
9.
Eur J Med Chem ; 115: 230-44, 2016 Jun 10.
Article En | MEDLINE | ID: mdl-27017551

In an attempt to explore novel and more potent antileishmanial compounds to diversify the current inhibitors, we pursued a medicinal chemistry-driven strategy to synthesize novel scaffolds with common pharmacophoric features of dihydropyrimidine and chalcone as current investigational antileishmanial compounds. Based on the reported X-ray structure of Pteridine reductase 1 (PTR1) from Leishmania major, we have designed a number of dihydropyrimidine-based derivatives to make specific interactions in PTR1 active site. Our lead compound 8i has shown potent in vitro antileishmanial activity against promastigotes of L. Major and Leishmania donovani with IC50 value of 0.47 µg/ml and 1.5 µg/ml respectively. The excellent in vitro activity conclusively revealed that our lead compound is efficient enough to eradicate both visceral and topical leishmaniasis. In addition, docking analysis and in silico ADMET predictions were also carried out. Predicted molecular properties supported our experimental analysis that these compounds have potential to eradicate both visceral and topical leishmaniasis.


Antiprotozoal Agents/pharmacology , Drug Design , Leishmania donovani/drug effects , Leishmania major/drug effects , Pyrimidines/pharmacology , Antiprotozoal Agents/chemical synthesis , Antiprotozoal Agents/chemistry , Chemistry, Pharmaceutical , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Molecular Docking Simulation , Molecular Structure , Parasitic Sensitivity Tests , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Structure-Activity Relationship
10.
J Enzyme Inhib Med Chem ; 24(1): 151-6, 2009 Feb.
Article En | MEDLINE | ID: mdl-18608771

In continuation of our previous study on the urease inhibition by a number of chalcones, 2,3-dihydro-1,5-benzothiazepines and 2,3,4,5-tetrahydro-1,5-benzothiazepines, FlexX docking has been exploited to get a deeper insight into the mechanism of their inhibitory action. A comparison of the IC(50) values of the active compounds reveals that, of the three classes of compounds studied, 2,3-dihydro-1,5-benzothiazepines were the most potent urease inhibitors. An in silico examination of these compounds showed that the activity is related to the interaction of ligand with the nickel metallocentre, its interaction with two amino acid residues, Asp224 and Cys322, in addition to the orientation of rings A and B in the catalytic core of the enzyme. The most active compound 2,3-dihydro-1,5-benzothiazepine (4) anchor tightly through a network of interactions with Ni701 and Ni702. This includes a number of hydrogen bonds and hydrophobic contacts with the amino acid residues in its vicinity. For their reduced analogs, the difference in the activity of different diastereomers has been observed to be configuration-dependent. This may be ascribed mainly to the difference in the orientation of ring B of the two stereoisomers and the extent of their interaction with Asp224 and Cys322 present in the catalytic core of the enzyme.


Computer Simulation , Urease/antagonists & inhibitors , Benzothiadiazines/pharmacology , Binding Sites , Chalcones/pharmacology , Enzyme Inhibitors/pharmacology , Inhibitory Concentration 50 , Ligands , Molecular Structure , Structure-Activity Relationship
11.
Bioorg Med Chem ; 16(16): 7691-7, 2008 Aug 15.
Article En | MEDLINE | ID: mdl-18650096

Solid-phase synthesis of a parallel library of 3'-hydroxy-2,3-dihydrobenzothiazepines has been carried out through [4+3] annulation of alpha,beta-unsaturated ketones with aminothiophenol, using Wang resin as solid support. The synthesized compounds were evaluated for their potential as antibacterial, tumor inhibitors as well as acetyl- and butyrylcholinesterase inhibitors. None of the compounds showed any significant antibacterial activity. However, quite a few compounds showed significant potential as crown gall tumor inhibitors. These results reflect a strong exploratory potential in search of new benzothiazepines as source of anticancer agents. The results of the inhibition of cholinesterase revealed that benzothiazepines have a greater potential as butyrylcholinesterase inhibitors as compared to acetylcholinesterase. Moreover, the substitution of hydroxy group at C-3 in ring A led to increased activity when compared to unsubstituted- and 2'-OH substituted benzothiazepines.


Thiazepines/chemical synthesis , Thiazepines/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/pharmacology , Cholinesterases/metabolism , Combinatorial Chemistry Techniques , Inhibitory Concentration 50 , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Plant Tumors , Thiazepines/chemistry
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