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1.
Mymensingh Med J ; 33(2): 350-355, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38557509

RESUMO

Evaluation of the in vitro antibacterial activity of Methanolic extracts isolated from Black pepper seeds (Piper nigrum L.) against two infection causing pathogens, Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. Between July 2022 and June 2023, this experimental study was conducted at the Mymensingh Medical College's Department of Pharmacology and Therapeutics in conjunction with the Department of Microbiology. Using the disc diffusion and broth dilution methods, the antibacterial activity of methanolic extract of black pepper seeds (MBPE) was evaluated at various doses. The solvents Methanol and 10.0% Di Methyl Sulfoxide (DMSO) were used to make the extract. Using the broth dilution procedure, the conventional antibiotic Ciprofloxacin was utilized and the outcome was contrasted with that of Methanol extracts. Methanolic extract of black pepper seeds (MBPE) at seven distinct concentrations (100, 80, 60, 40, 20, 10 and 5 mg/ml) were utilized, then later in chosen concentrations as needed to confirm the extracts' more precise margin of antimicrobial sensitivity. At 80 mg/ml and above doses of the MBPE, it had an inhibitory impact against the aforementioned microorganisms. For Staphylococcus aureus and Escherichia coli the MIC were 60 and 75 mg/ml in MBPE respectively. As of the MIC of Ciprofloxacin was 1µg/ml against Staphylococcus aureus and Escherichia coli. In comparison to MICs of MBPE for the test organisms, the MIC of Ciprofloxacin was the lowest. This study clearly shows that Staphylococcus aureus and Escherichia coli are sensitive to the methanolic extract of black pepper seeds' antibacterial properties.


Assuntos
Piper nigrum , Staphylococcus aureus , Humanos , Metanol , Extratos Vegetais/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Ciprofloxacina , Sementes , Escherichia coli
2.
Environ Res ; 195: 110857, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33581088

RESUMO

The nature of micro- and nanoplastics and their harmful consequences has drawn significant attention in recent years in the context of environmental protection. Therefore, this paper aims to provide an overview of the existing literature related to this evolving subject, focusing on the documented human health and marine environment impacts of micro- and nanoplastics and including a discussion of the economic challenges and strategies to mitigate this waste problem. The study highlights the micro- and nanoplastics distribution across various trophic levels of the food web, and in different organs in infected animals which is possible due to their reduced size and their lightweight, multi-coloured and abundant features. Consequently, micro- and nanoplastics pose significant risks to marine organisms and human health in the form of cytotoxicity, acute reactions, and undesirable immune responses. They affect several sectors including aquaculture, agriculture, fisheries, transportation, industrial sectors, power generation, tourism, and local authorities causing considerable economic losses. This can be minimised by identifying key sources of environmental plastic contamination and educating the public, thus reducing the transfer of micro- and nanoplastics into the environment. Furthermore, the exploitation of the potential of microorganisms, particularly those from marine origins that can degrade plastics, could offer an enhanced and environmentally sound approach to mitigate micro- and nanoplastics pollution.


Assuntos
Organismos Aquáticos , Poluentes Químicos da Água , Animais , Humanos , Microplásticos , Plásticos/toxicidade , Fatores Socioeconômicos , Poluentes Químicos da Água/análise
3.
Bioresour Technol ; 312: 123596, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32507633

RESUMO

This article reviews the production of renewable aviation fuels from biomass and residual wastes using gasification followed by syngas conditioning and Fischer-Tropsch catalytic synthesis. The challenges involved with gasifying wastes are discussed along with a summary of conventional and emerging gasification technologies. The techniques for conditioning syngas including removal of particulate matter, tars, sulphur, carbon dioxide, compounds of nitrogen, chlorine and alkali metals are reported. Recent developments in Fischer-Tropsch synthesis, such as new catalyst formulations are described alongside reactor technologies for producing renewable aviation fuels. The energy efficiency and capital cost of converting biomass and residual wastes to aviation fuels are major barriers to widespread adoption. Therefore, further development of advanced technologies will be critical for the aviation industry to achieve their stated greenhouse gas reduction targets by 2050.


Assuntos
Aviação , Gases de Efeito Estufa , Biomassa , Catálise , Alcatrões
4.
J Nanosci Nanotechnol ; 20(8): 5217-5222, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32126723

RESUMO

The present research focuses on the preparation of ZnO thin films both undoped and doped with varying Cu concentrations (0.0%, 0.8%, 3.0%, 5.0%, 10.0% and 20.0%) using sol-gel spin coating technique. The optical bandgap (Eg) for undoped films is recorded as 3.239 eV and shows a little increase to 3.248 eV when it is doped with 0.8% Cu concentration whereas further increase of Cu doping concentration, it is decreased from 3.248 eV to 3.107 eV for 20% Cu. The EU (Urbach Energy) is improved with the enhancement of Cu doping concentration. Ultraviolet (UV) and bluegreen band emissions are noticed from PL (photoluminescence) spectra. The UV peak intensities are diminished with increasing Cu doping concentration while the blue peaks intensities are amplified. These results illustrate that ZnO films doped with Cu meet the requirement for applications in different blue emission devices.

5.
Sci Rep ; 10(1): 4198, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144298

RESUMO

Herein, the preparation of gold nanoparticles-silk fibroin (SF-AuNPs) dispersion and its label-free colorimetric detection of the organophosphate pesticide, namely chlorpyrifos, at ppb level are reported. The silk fibroin solution was extracted from B. mori silk after performing degumming, dissolving and dialysis steps. This fibroin solution was used for synthesis of gold nanoparticles in-situ without using any external reducing and capping agent. X-ray Diffractometry (XRD), Field Emission Transmission Electron Microscopy (FETEM) along with Surface Plasmon Resonance based optical evaluation confirmed generation of gold nanoparticles within SF matrix. The resultant SF-AuNPs dispersion exhibited rapid and excellent colorimetric pesticide sensing response even at 10 ppb concentration. Effect of additional parameters viz. pH, ionic concentration and interference from other pesticide samples was also studied. Notably, SF-AuNPs dispersion exhibited selective colorimetric pesticide sensing response which can be calibrated. Furthermore, this method was extended to various simulated real life samples such as tap water, soil and agricultural products including plant residues to successfully detect the presence of chlorpyrifos pesticide. The proposed colorimetric sensor system is facile yet effective and can be employed by novice rural population and expert researchers alike. It can be exploited as preliminary tool for label-free colorimetric chlorpyrifos pesticide sensing in water and agricultural products.


Assuntos
Clorpirifos/química , Colorimetria/métodos , Fibroínas/química , Ouro/química , Nanopartículas Metálicas/química , Nanocompostos/química , Praguicidas/química , Fibroínas/ultraestrutura , Hidrodinâmica , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Difração de Raios X
6.
Bioresour Technol ; 299: 122557, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31918971

RESUMO

This article outlines the prospects and challenges of hydrogen production from biomass and residual wastes, such as municipal solid waste. Recent advances in gasification and pyrolysis followed by reforming are discussed. The review finds that the thermal efficiency of hydrogen from gasification is ~50%. The levelized cost of hydrogen (LCOH) from biomass varies from ~2.3-5.2 USD/kg at feedstock processing scales of 10 MWth to ~2.8-3.4 USD/kg at scales above 250 MWth. Preliminary estimates are that the LCOH from residual wastes could be in the range of ~1.4-4.8 USD/kg, depending upon the waste gate fee and project scale. The main barriers to development of waste to hydrogen projects include: waste pre-treatment, technology maturity, syngas conditioning, the market for clean hydrogen, policies to incentivize pioneer projects and technology competitiveness. The main opportunity is to produce low cost clean hydrogen, which is competitive with alternative production routes.


Assuntos
Hidrogênio , Eliminação de Resíduos , Biomassa , Conservação dos Recursos Naturais , Resíduos Sólidos , Tecnologia
7.
Waste Manag ; 102: 139-148, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677521

RESUMO

Catalytic pyrolysis is a useful technique for the conversion of scrap tyres into liquid fuels. Zeolite catalysts were employed in the pyrolysis of scrap tyres for the production of aromatic rich fuel. Deactivation of zeolite catalysts during pyrolysis reaction was investigated which played an important role in the product quality and composition. Herein, the performance of microporous zeolite catalysts and mesoporous MCM-41 catalyst was evaluated in a two-stage fixed bed reactor for the pyrolysis of scrap tyres. Comparative studies showed the increase in the production of aromatic compounds up to 23.7% over zeolite catalyst as compared to 18.7% over MCM-41 catalyst. However, Zeolite Y catalyst exhibited higher coke formation led to the rapid deactivation. The stability of zeolite catalysts is addressed by the incorporation of Cerium metal within the framework of two zeolite catalysts namely Zeolite Y and ZSM-5 through the ion-exchange technique. Parent and spent catalysts were characterised using synchrotron FT-IR spectroscopy, temperature-programmed desorption of ammonia (NH3-TPD), N2 Physisorption, scanning electron microscopy (SEM), inductively coupled plasma-optical emission spectrometry (ICP-OES), energy-dispersive X-ray spectroscopy (EDX), and hydrogen temperature-programmed reduction (H2-TPD). A higher percentage of aromatics were produced over the large pore Zeolite Y. Cerium ion-exchange decreased the formation of coke from 8.1% to 5.7% over submicron and large pore Zeolite Y catalyst. Moreover, naphthalene production decreased over both Ce-Zeolite Y and Ce-ZSM-5.


Assuntos
Cério , Coque , Zeolitas , Catálise , Pirólise , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Diagn Cytopathol ; 48(2): 118-127, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31697443

RESUMO

BACKGROUND: Fine needle aspiration cytology (FNAC) assisted with scrotal ultrasonography is the best preoperative diagnostic modality for palpable epididymal nodules. It also aids in their successive remedial approach as well as serves semi-therapeutically in cystic lesions. The objectives of this study are to recognize the spectrum of pathological conditions giving rise to epididymal nodules, then to compare them with corresponding ultrasound images, and to evaluate the histological features wherever practicable. METHODS: Total 62 patients underwent FNAC as well as sonographic evaluation for their epididymal nodules. Histopathology was performed in only 20 cases. RESULTS: Epididymitis either caused by tuberculosis (30.6%), or in its acute (11.3%) and chronic (8.1%) forms remained the commonest cytological diagnosis. Neoplastic lesions included mostly adenomatoid tumors (8.1%), and another case of seminomatous spread from ipsilateral testicular primary. Nineteen of the excised masses corroborated with their respective cytodiagnoses. The discrepant lesion was actually a papillary cystadenoma, which was cytologically misinterpreted as adenomatoid tumor. CONCLUSIONS: FNAC becomes the first-hand investigative measure for epididymal nodules, by virtue of its early, easy and highly accurate diagnostic implications. It segregates the patients into proper therapeutic protocol and thereby estranges those who really need operative management. When deployed together with ultrasound, the diagnostic accuracy of FNAC improves further.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Epididimo/patologia , Espermatocele/patologia , Ultrassonografia/métodos , Adolescente , Adulto , Idoso , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/normas , Epididimo/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Espermatocele/diagnóstico por imagem , Ultrassonografia/normas
9.
Mymensingh Med J ; 28(4): 779-791, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31599241

RESUMO

Evaluation of the in vitro antibacterial activity of aqueous and ethanolic extracts isolated from Clove (Syzygium aromaticum) buds against three food borne pathogens, gram-positive Staphylococcus aureus and gram-negative Escherichia coli & Pseudomonas aeruginosa. This interventional study was carried out during the period of July 2018 to June 2019 in the Department of Pharmacology and Therapeutics with the collaboration of Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh. The antibacterial activity was tested at different concentrations of both extracts of spice by using disc diffusion & broth dilution method. The extracts were prepared by using solvents aqueous & ethanol. The test microorganisms were also tested for their activity against a standard antibiotic Gentamicin (80mg) by broth dilution method and the result was compared with that of Aqueous and Ethanolic extracts. Aqueous and ethanolic extracts of clove had inhibitory activity against the test bacteria. Among different concentrations of the ACE, 500µg/ml & above concentration showed inhibitory effect against Staphylococcus aureus & Escherichia coli and 700µg/ml & above concentration showed inhibitory effect against Pseudomonas aeruginosa. In case of ECE, 500µg/ml & above concentration showed inhibitory effect against aforesaid bacteria. In disc diffusion method, S. aureus was found to be most susceptible to ACE (30.5mm) & Pseudomonas aeruginosa was found to be most susceptible to ECE (38mm). Minimum inhibitory concentrations (MIC) of ECE were lower than ACE for the test bacteria except Staphylococcus aureus where MICs of ACE & ECE were the same. This result was also compared against a standard antibiotic Gentamicin where the MICs of Gentamicin were lower in comparison to MICs of ACE & ECE. The present study showed that aqueous and ethanolic extracts of Clove demonstrated antibacterial effects against food borne pathogens.


Assuntos
Antibacterianos/toxicidade , Extratos Vegetais/toxicidade , Syzygium , Bangladesh , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt C: 1698-701, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25467659

RESUMO

During illumination of the MgB2:Cr2O3 films it was established substantial spectral shift of the infrared spectra in the vicinity of 20-50cm(-1). The excitations were performed by nanosecond Er:glass laser operating at 1.54µm and by microsecond 10.6µm CO2 laser. The spectral shifts of the IR maxima were in opposite spectral directions for the two types of lasers. This one observed difference correlates well with spectral shift of their critical temperatures. The possible explanation is given by performance of DFT calculations of the charge density redistribution and the time kinetics of the photovoltaic response. To understand the kinetics of the photoinduced processes the time kinetics of photoresponse was done for the particular laser wavelengths.

11.
Invest New Drugs ; 29(4): 523-33, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20069337

RESUMO

DNA intercalating molecules are promising chemotherapeutic agents. In the present study, a novel DNA intercalating compound of pyrimido[4',5':4,5]selenolo(2,3-b)quinoline series having 8-methyl-4-(3 diethylaminopropylamino) side chain is studied for its chemotherapeutic properties. Our results showed that 8-methyl-4-(3 diethylaminopropylamino) pyrimido [4',5':4,5] selenolo(2,3-b)quinoline (MDPSQ) induces cytotoxicity in a time- and concentration-dependent manner on leukemic cell lines. Both cell cycle analysis and tritiated thymidine assays revealed that MDPSQ affects DNA replication. Treatment with MDPSQ resulted in both elevated levels of DNA strand breaks and repair proteins, further indicating its cytotoxic effects. Besides, Annexin V/PI staining revealed that MDPSQ induces cell death by triggering necrosis rather than apoptosis.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Elipticinas/química , Elipticinas/farmacologia , Leucemia/patologia , Necrose/induzido quimicamente , Compostos Organosselênicos/farmacologia , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , DNA de Neoplasias/biossíntese , Ensaios de Seleção de Medicamentos Antitumorais , Instabilidade Genômica/efeitos dos fármacos , Humanos , Necrose/patologia , Proteínas de Neoplasias/metabolismo , Compostos Organosselênicos/química , Fosfatidilserinas/metabolismo , Propídio/metabolismo
12.
Invest New Drugs ; 29(5): 873-82, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20424886

RESUMO

DNA intercalating molecules are promising anticancer agents. Polycyclic aromatic molecules such as ellipticine intercalate into double-stranded DNA and affect major physiological functions. In the present study, we have characterized two molecules with the same chemical backbone but different side chains, namely 8-methoxy pyrimido[4',5':4,5]thieno (2,3-b)quinoline-4(3H)-one (MPTQ) and 4-morpholino pyrimido[4',5':4,5]thieno(2,3-b)quinoline (morpho-PTQ) at the 8th and 4th position, respectively. Although both MPTQ and morpho-PTQ show similar biophysical properties with high DNA affinity, here we show that they differ in their biological activities. We find that MPTQ is many fold more potent than morpho-PTQ and is cytotoxic against different leukemic cell lines. IC(50) value of methoxy PTQ was estimated between 2-15 µM among the leukemic cells studied, while it was more than 200 µM when morpho-PTQ was used. Cell cycle analysis shows an increase in sub-G1 phase, without any particular cell cycle arrest. Annexin V staining in conjunction with comet assay and DNA fragmentation suggest that MPTQ induces cytotoxicity by activating apoptosis. Thus the observed low IC(50) value of MPTQ makes it a promising cancer chemotherapeutic agent.


Assuntos
Apoptose/efeitos dos fármacos , Substâncias Intercalantes/farmacologia , Leucemia/patologia , Morfolinos/farmacologia , Quinolinas/farmacologia , Tiofenos/farmacologia , Anexina A5/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fase G1/efeitos dos fármacos , Humanos , Substâncias Intercalantes/química , Leucemia/metabolismo , Microscopia Confocal , Morfolinos/química , Fosfatidilserinas/metabolismo , Quinolinas/química , Tiofenos/química
13.
Invest New Drugs ; 28(1): 35-48, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19142583

RESUMO

DNA intercalators are one of the most commonly used chemotherapeutic agents. Novel intercalating compounds of pyrimido[4',5':4,5]selenolo(2,3-b)quinoline series having a butylamino or piperazino group at fourth position (BPSQ and PPSQ, respectively) are studied. Our results showed that BPSQ induced cytotoxicity whereas PPSQ was cytostatic. The cytotoxicity induced by BPSQ was concentration- and time-dependent. Cell cycle analysis and tritiated thymidine assay revealed that BPSQ affects the cell cycle progression by arresting at S phase. The absence of p-histone H3 and reduction in the levels of PCNA in the cells treated with BPSQ further confirmed the cell cycle arrest. Further, annexin V staining, DNA fragmentation, nuclear condensation and changes in the expression levels of BCL2/BAD confirmed the activation of apoptosis. Activation of caspase 8 and lack of cleavage of caspase 9, caspase 3 and PARP suggest the possibility of BPSQ triggering extrinsic pathway for induction of apoptosis, which is discussed. Hence, we have identified a novel compound which would have clinical relevance in cancer chemotherapeutics.


Assuntos
Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , DNA/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Substâncias Intercalantes/farmacologia , Leucemia/patologia , Compostos Organosselênicos/farmacologia , Quinolinas/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Morte Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Heterocíclicos de 4 ou mais Anéis/química , Humanos , Substâncias Intercalantes/química , Células K562 , Compostos Organosselênicos/química , Fosfatidilserinas/metabolismo , Quinolinas/química
14.
Bioorg Med Chem ; 17(6): 2576-84, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19243955

RESUMO

In order to explore the anticancer effect associated with the thiazolidinone framework, several 2-(5-((5-(4-chlorophenyl)furan-2-yl)methylene)-4-oxo-2-thioxothiazolidin-3-yl)acetic acid derivatives 5(a-l) were synthesized. Variation in the functional group at C-terminal of the thiazolidinone led to set of compounds bearing amide moiety. Their chemical structures were confirmed by (1)H NMR, IR and Mass Spectra analysis. These thiazolidinone compounds containing furan moiety exhibits moderate to strong antiproliferative activity in a cell cycle stage-dependent and dose dependent manner in two different human leukemia cell lines. The importance of the electron donating groups on thiazolidinone moiety was confirmed by MTT and Trypan blue assays and it was concluded that the 4th position of the substituted aryl ring plays a dominant role for its anticancer property. Among the synthesized compounds, 5e and 5f have shown potent anticancer activity on both the cell lines tested. To rationalize the role of electron donating group in the induction of cytotoxicity we have chosen two molecules (5e and 5k) having different electron donating group at different positions. LDH assay, Flow cytometric analysis and DNA fragmentation suggest that 5e is more cytotoxic and able to induce the apoptosis.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Tiazolidinedionas/síntese química , Tiazolidinedionas/farmacologia , Tionas/síntese química , Tionas/farmacologia , Ciclo Celular , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Citometria de Fluxo , Humanos , Análise Espectral/métodos
15.
J Photochem Photobiol B ; 94(1): 13-9, 2009 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-18945623

RESUMO

Circular dichroism, hydrodynamic methods, absorbance and fluorescence titration's were employed to study the interaction of 8-chloropyrimido[4',5':4,5]thieno(2,3-b)quinolin-4(3H)-one (chloro-PTQ) and 4-morpholinopyrimido[4',5':4,5]thieno(2,3-b)quinoline (morpholino-PTQ) with DNA. The association constant of chloro-PTQ and morpholino-PTQ were of the order of 10(5) and 10(6) M(-1). The fluorescence properties at ionic strength of 10mM are best fit by the neighbor exclusion model, with Ki of 0.3 x 10(4) M(-1) to 3.2 x 10(6) M(-1). CD spectra indicate that stacking of these compounds with DNA induces strong helicity in the usually disordered structure of the double strand. Viscosity experiments with sonicated rod like DNA fragments, produced a calculated length of 2.4A/bound of chloro/morpholino-PTQ molecule. The binding of chloro/morpholino-PTQ to DNA increased the melting temperature by about 1.5-7.0 degrees C. The cytotoxicity of these compounds on K-562, HL-60, Colo-205 and B16F10 melanoma are quite similar and IC(50) was in the range of 1.1-8muM. The anticancer efficacy against B16F10 melanoma has provided evidence of major anticancer activity for morpholino-PTQ. Single or multiple i.p. doses of compounds showed high level of activity against the subcutaneous (s.c.) grafted B16 melanoma with a significant increase in life span (161% and 272%). The aim of this study was to analyze the physicochemical properties of the chloro/morpholino-PTQ in an attempt to understand their superior biological activity. This research offers a new intercalation functional group to DNA targeted drug design.


Assuntos
Antineoplásicos/química , Antineoplásicos/toxicidade , Compostos Clorados/química , Pirimidinas/química , Quinolinas/química , Quinolinas/toxicidade , Compostos de Sulfidrila/química , Animais , Bovinos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Compostos Clorados/toxicidade , Dicroísmo Circular , DNA/química , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Morfolinas/química , Transplante de Neoplasias , Espectrofotometria , Titulometria , Viscosidade
16.
Toxicol Mech Methods ; 17(3): 135-45, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-20020962

RESUMO

ABSTRACT The genotoxic effect of the anticancer drugs Oxo-PTQ, Morpholino-PTQ, and Chloro-PTQ were studied in mice bone marrow by means of chromosome aberrations and micronucleus assay. These drugs, at dose levels of 21.42, 28.57, and 35.71 mg/kg b.w., respectively, were given to mice in a single application via the intraperitoneal route. Marrow was collected at 24, 48, and 72 h after the application. The chromosome aberrations and micronucleus assay were done according to standard procedures. These compounds gave rise to an increase in the number of micronuclei in a dose-dependent manner. The number of micronucleated polychromatic erythrocytes showed a maximum at 24 h, and there was partial recovery at 72 h. Chromosome aberrations increased significantly as compared to normal controls when treated with Oxo-PTQ followed by Morpholino-PTQ at 21.42 mg/kg b.w. (48 h). Statistically significant sperm abnormalities also revealed the genotoxic potency of these drugs. Our results suggest that the Pyrimido[4(I),5(I):4,5]thieno(2,3-b)quinoline drugs owe at least some of their cytotoxicity to their genotoxic effects, which seem to be mediated through interaction with topoisomerase II.

17.
Drug Chem Toxicol ; 28(3): 345-57, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16051559

RESUMO

8-methoxypyrimido[4',5':4,5]thieno(2,3-b)quinoline-4(3H)-one (MPTQ) is known to have antitumor and cytotoxic activities on various types of tumors. This compound showed a strong clastogenic effect on bone marrow cells of Swiss albino mice treated in vivo (17.5-35 mg/kg body weight). MPTQ induced micronuclei formation (MN) at doses of 17.5, 23.3, and 35 mg/kg. Dose and time-yield effect of MPTQ was studied in the case of chromosome aberration assay. MPTQ induced a statistically significant increase in the frequency of chromosome aberrations and micronuclei induction. The drug induced significant abnormal sperms even in the sperm shape abnormality assay. Based on the data reported in the literature, we have tried to establish the relationship between the clastogenic effect observed and process of MPTQ intercalation into DNA and the formation of protein-associated DNA-strand breaks probably promoted by topoisomerase enzymes.


Assuntos
DNA/efeitos dos fármacos , Substâncias Intercalantes/toxicidade , Mutagênicos , Quinolinas/toxicidade , Tiofenos/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/ultraestrutura , Aberrações Cromossômicas/induzido quimicamente , Dano ao DNA/efeitos dos fármacos , Masculino , Camundongos , Testes para Micronúcleos , Testes de Mutagenicidade , Tamanho do Órgão/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/ultraestrutura
18.
Bioorg Med Chem Lett ; 15(15): 3584-7, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15967664

RESUMO

In a three-step sequence, an array of angularly fused polycyclic heterocycles with coumarin, benzofuran and pyridine rings were synthesized from 4-bromomethylcoumarins and salicylonitrile. All the final compounds were fully characterized and screened for anti-microbial, anti-inflammatory and analgesic activities. Several compounds exhibited promising inflammation inhibiting and anti-microbial properties.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Cumarínicos/farmacologia , Medição da Dor/efeitos dos fármacos , Analgésicos/síntese química , Analgésicos/farmacologia , Animais , Antibacterianos/síntese química , Anti-Inflamatórios/síntese química , Benzofuranos/síntese química , Benzofuranos/farmacologia , Contagem de Colônia Microbiana , Cumarínicos/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Piridinas/síntese química , Piridinas/farmacologia , Relação Estrutura-Atividade
19.
Indian J Med Res ; 119(5): 198-205, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15218983

RESUMO

BACKGROUND & OBJECTIVES: The compounds containing novel tetracyclic condensed quinoline ring system is of interest because of its close relationship with anticancer drug ellipticine. 8-Methoxypyrimido[4(1),5(1):4,5]thieno(2,3-b)quinoline-4(3H)-one (MPTQ) was investigated to study its effect on in vitro growth inhibition and clonogenic cell survival assay on three tumour cell lines, human promyelocytic leukemia HL-60, melanoma B16F10 and neuro 2a. A systematic study was carried out to evaluate its antitumour efficacy against B16 murine melanoma. Antiinflammatory and analgesic activities of MPTQ were also studied. METHODS: The cytotoxicity of MPTQ on HL-60, B16F10 and neuro 2a cells was estimated by trypan blue exclusion test. The antitumour activity was evaluated using single dose, multiple/daily injections (days 3-6) or intermittent treatments over two weeks against s.c. implanted B16melanoma, both in terms of increased life span and tumour growth inhibition. Antiinflammatory activity was seen on carrageenan induced hind paw oedema. Counting the number of abdominal constrictions after the injection of acetic acid assessed the analgesic response. RESULTS: MPTQ is cytotoxic to all the cell lines tested and ID50 being in the range of 0.08-1.0 microM. MPTQ was studied for anticancer activity in the clonogenic assay. Drug was applied over a wide dose range by 24 h exposure, yielding clear dose-response effects. In vivo antitumour efficacy against B16 melanoma showed evidence of major antitumour activity for MPTQ. Single and multiple i.p. doses of drug proved high level activity against the s.c. grafted B16melanoma, significantly increasing survival (P<0.001) and inhibiting tumour growth (T/C of 3.0%). A reduction (76.48%) in paw volume was noted in 40 mg/kg dose of which was comparable to antiinflammatory activity of 150 mg/kg i.p. of phenylbutazone. Analgesic activity was found to be of peripheral type as there was reduction of 74 per cent in writhing response by MPTQ in dose of 40 mg/kg in mice. INTERPRETATION & CONCLUSION: The results suggested that the compounds containing pyrimidothienoquinoline system particularly 8-methoxy derivative might be potentially useful antitumour agent. We conclude that the correlation of physicochemical properties of the new series of pyrimidothienoquinolines with their pharmacological properties, might help in trying to understand the mechanism of pyrimidothienoquinolines series.


Assuntos
Antineoplásicos/metabolismo , Substâncias Intercalantes/metabolismo , Quinolinas/metabolismo , Tiofenos/metabolismo , Analgésicos/metabolismo , Animais , Anti-Inflamatórios/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Quinolinas/química , Ratos , Ratos Wistar , Células Tumorais Cultivadas
20.
Indian J Pathol Microbiol ; 46(1): 55-6, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15027722

RESUMO

T-cell-rich B-cell lymphoma (TCRBCL) is a recently described variant of diffuse Non-Hodgkin's lymphoma (NHL) which requires immunohistochemical analysis for its recognition. Striking similarities exist between TCRBCL and lymphocyte predominant Hodgkin's Disease (LPHD) due to the presence of Reed-Sternberg (R-S) like cells. Hence, the need for distinction between the two is of utmost importance from a prognostic and therapeutic stand point. The present study describes a case of TCRBCL, misdiagnosed as Hodgkin's Disease (HD) on fine needle aspiration (FNA) cytology. However, immunostaining of paraffin embedded sections corrected the cytological diagnosis.


Assuntos
Linfoma de Células B/patologia , Células de Reed-Sternberg/patologia , Linfócitos T/patologia , Adulto , Biópsia por Agulha , Humanos , Masculino
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