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1.
Sci Rep ; 12(1): 12843, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35902676

RESUMO

In the present study, a method for the synthesis of gelatin-stabilized copper oxide nanoparticles was developed. Synthesis was carried out by direct chemical precipitation. Copper sulfate, chloride, and acetate were used as precursors for the copper oxide synthesis. Gelatin was used as a stabilizer. It was found that the formation of monophase copper oxide II only occurred when copper acetate was used as a precursor. Our results showed that particles of the smallest diameter are formed in an aqueous medium (18 ± 6 nm), and those of th largest diameter-in an isobutanol medium (370 ± 131 nm). According to the photon correlation spectroscopy data, copper oxide nanoparticles synthesized in an aqueous medium were highly stable and had a monomodal size distribution with an average hydrodynamic radius of 61 nm. The study of the pH effect on the colloidal stability of copper oxide nanoparticles showed that the sample was stable in the pH range of 6.8 to 11.98. A possible mechanism for the pH influence on the stability of copper oxide nanoparticles is described. The effect of the ionic strength of the solution on the stability of the CuO nanoparticles sol was also studied, and the results showed that Ca2+ ions had the greatest effect on the sample stability. IR spectroscopy showed that the interaction of CuO nanoparticles with gelatin occurred through the hydroxyl group. It was found that CuO nanoparticles stabilized with gelatin have a fungicidal activity at concentration equivalent 2.5 · 10-3 mol/L and as a material for food nanopackaging can provide an increase in the shelf life of products on the example of strawberries and tomatoes. We investigated the possibility of using methylcellulose films modified with CuO nanoparticles for packaging and storage of hard cheese "Holland". The distribution of CuO nanoparticles in the methylcellulose film was uniform. We found that methylcellulose films modified with CuO nanoparticles inhibited the growth and development of QMAFAM, coliforms, yeast and mold in experimental cheese sa mples. Our research has shown that during the cheese storage in thermostat at 35 ± 1 °C for 7 days, CuO nanoparticles migrated to the product from the film. Nevertheless, it is worth noting that the maximum change in the concentration of copper in the experimental samples was only 0.12 µg/mg, which is not a toxic concentration. In general, the small value of migration of CuO nanoparticles confirms the high stability of the developed preparation. Our results indicated that the CuO nanoparticles stabilized with gelatin have a high potential for use in food packaging - both as an independent nanofilm and as part of other packaging materials.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Cobre/química , Embalagem de Alimentos , Gelatina , Nanopartículas Metálicas/química , Metilcelulose , Óxidos
2.
Indian J Cancer ; 53(2): 265-269, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28071624

RESUMO

INTRODUCTION: The worldwide incidence of head and neck malignancy exceeds half a million cases annually. In radiotherapy (RT), conventional fractionation comprises giving five fractions per week from Monday to Friday. Accelerated RT includes administration of six fractions per week is being advocated. It gives better locoregional control and the median overall treatment time is 39 days as compared to 46 days in conventional group. Our study involved comparison of conventional versus accelerated RT with concurrent chemotherapy, in evaluation of local control and toxicity in the two arms. MATERIALS AND METHODS: Sixty patients of locally advanced squamous cell carcinoma head and neck region were studied. All the patients received cisplatin (30 mg/m2) weekly during the therapy. The patients received RT dose of 70 Gray (Gy) in 35 fractions (#). The patients were randomly assorted into two groups: Group 1 - Study group (n = 30) - Six fractions RT per week (Monday-Saturday). Group 2 - Control group (n = 30) - Five fractions RT per week (Monday-Friday). During and after the treatment, locoregional control, acute and late radiation toxicity were assessed. Results and Observation: There was no significant difference between the two schedules regarding locoregional control rate. The Grade 3 or higher acute toxicities were significantly higher in the accelerated arm although there was no significant difference in late toxicities between the two arms. CONCLUSION: Accelerated fractionation regimen was not more efficacious than conventional fractionation in the treatment of previously untreated head and neck carcinoma.


Assuntos
Fracionamento da Dose de Radiação , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Dosagem Radioterapêutica/normas , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade
3.
Indian J Cancer ; 53(3): 372-376, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28244461

RESUMO

BACKGROUND: Induction chemotherapy (ICT) in patients with head and neck cancer has been studied since a long time. The addition of taxanes to the cisplatin and 5-fluorouracil (5FU) (PF) regimen results in superior antitumor activity. We did this study to see the response and toxicity of ICT with cisplatin and ifosfamide followed by concurrent chemoradiotherapy (CRT) in locally advanced, unresectable squamous cell carcinoma of head and neck (SCCHN). AIMS: The aim of this study was to see the results of ICT using cisplatin and ifosfamide regimen in locally advanced unresectable SCCHN in terms of acute and chronic toxicity and response to treatment. MATERIALS AND METHODS: Patients with Stage III and IV, nonmetastatic SCCHN were enrolled in the study. They were given two cycles of ICT with cisplatin and ifosfamide followed by CRT. RESULTS: After ICT, the overall response rate (ORR) was 75.0% at the primary site and 70.0% at the nodal site. ORR for combined primary and nodal disease was observed to be 67.5%. The complete response (CR) and partial response (PR) for combined primary and nodal site were seen in 4 (10.0%) and 23 (57.5%) patients. Of 32 patients who received CRT after ICT, CR was 53.1% and PR was 31.3%. Mucositis, skin reaction, and pharyngeal and laryngeal toxicities were the most common but tolerable. CONCLUSION: ICT with cisplatin and ifosfamide gives comparable results to the standard paclitaxel, PF regimen. We conclude that this combination regimen for ICT is not only an economical alternative of taxol-based regimen but also well tolerated by the patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Cisplatino/administração & dosagem , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Ifosfamida/administração & dosagem , Quimioterapia de Indução , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Prospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço
4.
Indian J Cancer ; 53(3): 402-407, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28244470

RESUMO

INTRODUCTION: In our study, we have treated cases of early glottic carcinoma by two different dose-fractionation schedules in relation to overall treatment time. MATERIALS AND METHODS: This is an analysis of 29 patients with invasive, previously untreated T1and T2squamous cell carcinoma of true vocal cord that was treated by radical radiation therapy. DOSE AND FRACTIONATION: All patients were treated with a continuous course of radiation therapy with once-daily fractionation. All the patients were treated 5 days a week from Monday to Friday. The fractionation regime was either: (1) 62.5 Gy/25fractions/5 weeks at 2.5 Gy fractions (Regimen 1), (2) 70 Gy/35 fractions/7 weeks at 2 Gy/fraction (Regimen 2). Regimen 1 included 15/29 patients (51.72%) and Regimen 2 included 14/29 patients (48.27%). Patients were evaluated for: (1) Locoregional control, (2) acute and late radiation toxicities, (3) quality of voice. RESULTS AND OBSERVATION: There was no significant difference in terms of locoregional control rate, acute and late radiation toxicities in both groups. Voice quality during and after radiation was comparable in both arms. CONCLUSION: Use of high dose per fraction schedule with shorter duration of treatment results in comparable local control as well as the quality of voice to the protracted course of radiotherapy without increase in treatment-related toxicities. Shorter overall treatment time can be of great advantage in terms of time, cost, comfort, and acceptability by the patients.


Assuntos
Neoplasias Laríngeas/radioterapia , Fracionamento da Dose de Radiação , Feminino , Humanos , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
5.
Appl Radiat Isot ; 105: 20-25, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26226219

RESUMO

The proton beam energy of an isochronous 18MeV cyclotron was determined using a novel version of the stacked copper-foils technique. This simple method used stacked foils of natural copper forming 'thick' targets to produce Zn radioisotopes by the well-documented (p,x) monitor-reactions. Primary beam energy was calculated using the (65)Zn activity vs. depth profile in the target, with the results obtained using (62)Zn and (63)Zn (as comparators) in close agreement. Results from separate measurements using foil thicknesses of 100, 75, 50 or 25µm to form the stacks also concurred closely. Energy was determined by iterative least-squares comparison of the normalized measured activity profile in a target-stack with the equivalent calculated normalized profile, using 'energy' as the regression variable. The technique exploits the uniqueness of the shape of the activity vs. depth profile of the monitor isotope in the target stack for a specified incident energy. The energy using (65)Zn activity profiles and 50-µm foils alone was 18.03±0.02 [SD] MeV (95%CI=17.98-18.08), and 18.06±0.12MeV (95%CI=18.02-18.10; NS) when combining results from all isotopes and foil thicknesses. When the beam energy was re-measured using (65)Zn and 50-µm foils only, following a major upgrade of the ion sources and nonmagnetic beam controls the results were 18.11±0.05MeV (95%CI=18.00-18.23; NS compared with 'before'). Since measurement of only one Zn monitor isotope is required to determine the normalized activity profile this indirect yet precise technique does not require a direct beam-current measurement or a gamma-spectroscopy efficiency calibrated with standard sources, though a characteristic photopeak must be identified. It has some advantages over published methods using the ratio of cross sections of monitor reactions, including the ability to determine energies across a broader range and without need for customized beam degraders.


Assuntos
Ciclotrons/estatística & dados numéricos , Prótons , Radioisótopos de Zinco , Cobre , Humanos , Radiometria/estatística & dados numéricos , Radioisótopos de Zinco/análise
6.
Phys Chem Chem Phys ; 17(12): 7888-97, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25721090

RESUMO

In this paper the three new narrow bandgap D­A conjugated copolymers P1, P2 and P3 based on different weak donor fused thiophene-imidazole containing derivatives and the same benzothiadiazole acceptor unit were synthesized by Stille cross-coupling polymerization and characterized by 1H NMR, elemental analysis, GPC, TGA, DSC. These copolymers exhibit intensive absorbance in the range 350­900 nm and the optical bandgap lies in the range of 1.50­1.61 eV, which corresponds to the maximum photon flux of the solar spectrum. The electrochemical bandgap derived from cyclic voltammetry varies within the limits 1.47­1.65 eV and is approximately very close to the optical bandgap. The highest occupied molecular orbital (HOMO) energy level of all copolymers is deep lying (−5.24 eV and −5.37 eV and −5.25 eV for P1, P2 and P2, respectively) which shows that copolymers have good stability in the air and assured a higher open circuit voltage (Voc) for polymer BHJ solar cells. These copolymers were used as donors along with PC71BM and the BHJ polymer solar cells based on P1:PC71BM, P2:PC71BM and P3:PC71BM processed from chloroform (CF) solvent with 3 v% DIO as an additive showed an overall PCE of 4.55%, 6.76% and 5.16%, respectively.

7.
Mater Sci Eng C Mater Biol Appl ; 33(8): 4952-7, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24094209

RESUMO

Characteristics of X-ray transmissions were investigated for epoxy composites filled with 2-10 vol% WO3 loadings using synchrotron X-ray absorption spectroscopy (XAS) at 10-40 keV. The results obtained were used to determine the equivalent X-ray energies for the operating X-ray tube voltages of mammography and radiology machines. The results confirmed the superior attenuation ability of nano-sized WO3-epoxy composites in the energy range of 10-25 keV when compared to their micro-sized counterparts. However, at higher synchrotron radiation energies (i.e., 30-40 keV), the X-ray transmission characteristics were similar with no apparent size effect for both nano-sized and micro-sized WO3-epoxy composites. The equivalent X-ray energies for the operating X-ray tube voltages of the mammography unit (25-49 kV) were in the range of 15-25 keV. Similarly, for a radiology unit operating at 40-60 kV, the equivalent energy range was 25-40 keV, and for operating voltages greater than 60 kV (i.e., 70-100 kV), the equivalent energy was in excess of 40 keV. The mechanical properties of epoxy composites increased initially with an increase in the filler loading but a further increase in the WO3 loading resulted in deterioration of flexural strength, modulus and hardness.


Assuntos
Compostos de Epóxi/química , Óxidos/química , Proteção Radiológica/instrumentação , Tungstênio/química , Dureza , Tamanho da Partícula , Raios X
8.
Appl Radiat Isot ; 71(1): 62-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23123305

RESUMO

The effect of particle size, filler loadings and x-ray tube voltage on the x-ray transmission in WO(3)-epoxy composites has been investigated using the mammography unit and a general radiography unit. Results indicate that nano-sized WO(3) has a better ability to attenuate the x-ray beam generated by lower tube voltages (25-35 kV) when compared to micro-sized WO(3) of the same filler loading. However, the effect of particle size on x-ray transmission was negligible at the higher x-ray tube voltages (40-120 kV).


Assuntos
Compostos de Epóxi/química , Óxidos/química , Tamanho da Partícula , Tungstênio/química , Raios X
9.
Open Vet J ; 3(1): 17-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26623307

RESUMO

An oblique fracture of the distal third of the right metatarsus in a three-year-old dromedary heifer weighing about 300 kilograms was immobilized with a 4.5 mm broad-webbed 12-hole dynamic compression bone plate and two interfragmental compression screws. The animal showed slight lameness after 16 weeks of surgery that disappeared after removal of the plate. The result was quite encouraging and the fracture healed in 16 weeks without major complications. It is concluded that the fracture of this bone can be successfully handled with bone plating at least in young, light weight animals.

10.
Indian J Cancer ; 49(3): 277-82, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23238144

RESUMO

Breast cancer is known from ancient time,and the treatment strategy evolved as our understanding of the disease changed with time. In 460 BC Hippocrates described breast cancer as a humoral disease and presently after a lot of studies breast cancer is considered as a local disease with systemic roots. For most of the twentieth century Halsted radical mastectomy was the "established and standardized operation for cancer of the breast in all stages, early or late". New information about tumor biology and its behavior suggested that less radical surgery might be just as effective as the more extensive one. Eventually, with the use of adjuvant therapy likeradiation and systemic therapy, the extent of surgical resection in the breast and axilla got reduced further and led to an era of breast conservation. The radiation treatment of breast cancer has evolved from 2D to 3D Conformal and to accelarated partial breast irradiation, aiming to reduce normal tissue toxicity and overall treatment time. Systemic therapy in the form of hormone therapy, chemotherapy and biological agents is now a well-established modality in treatment of breast cancer. The current perspective of breast cancer management is based on the rapidly evolving and increasingly integrated study on the genetic, molecular , biochemical and cellular basis of disease. The challenge for the future is to take advantage of this knowledge for the prediction of therapeutic outcome and develop therapies and rapidly apply more novel biologic therapeutics.


Assuntos
Neoplasias da Mama/terapia , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Tamoxifeno/uso terapêutico , Neoplasias da Mama/história , Ensaios Clínicos como Assunto , Tratamento Farmacológico/história , Tratamento Farmacológico/tendências , Feminino , História do Século XX , História do Século XXI , História Antiga , História Medieval , Humanos , Mastectomia Radical/tendências , Terapia de Alvo Molecular , Medicina de Precisão , Radioterapia
11.
Med Chem ; 8(3): 428-35, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22385188

RESUMO

The 2,4,5-triaryl imidazole derivatives (API) were designed, screened and characterized kinetically & thermodynamically against Pepsin and their activity was also tested on the in silico platform. The docking studies of API with Pepsin show that these are novel and unique inhibitors of Aspartic protease. Drug like properties of these compounds were validated in silico based on Lipinski's rule of Five by calculating ClogP, LogS, H-bond acceptors, H-Bond donors, rotational bonds, PSA, PB and BBB values. The Et/Ki and Et/Km values of API show that they follow the Michaelis-Menten kinetics. The binding of inhibitors with proteases was explained by using Van't Hoff plot and thermodynamic parameters viz. free energy (ΔG), Entropy (ΔS) and Enthalpy (ΔH). The Van't Hoff analysis showed that the value of Ki decreases with increase in temperature and the binding of the inhibitor are entropically driven. API act as new potent aspartic protease inhibitors with Ki, for Pepsin, ranges from 3.7 µM to 16.7 µM. Strong hydrophobic groups at C-4 & C-5 position in API favor binding of inhibitors with Pepsin. Experiments also showed that among C-2 aryl substituted imidazole, a 4-substitution on aryl ring is preferred and less polar substituent makes the molecule more active whereas polar substituents at 2-position on C-2 aryl ring makes the molecule less active. The docking studies of API with Pepsin further intensify and validate our results.


Assuntos
Ácido Aspártico Proteases/antagonistas & inibidores , Desenho de Fármacos , Imidazóis/síntese química , Imidazóis/farmacologia , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacologia , Ácido Aspártico Proteases/metabolismo , Relação Dose-Resposta a Droga , Imidazóis/química , Cinética , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteases/química , Relação Estrutura-Atividade , Termodinâmica
12.
Plant Dis ; 95(1): 75, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30743680

RESUMO

Broomrape (Orobanche aegyptiaca Pers.), an important obligate root parasitic weed in India, has a wide host range including several members of the Solanaceae, Leguminaceae, and Brassicaceae families, among others. Orobanche plants produce thousands of tiny seeds (250 × 300 µm), which can remain viable in the soil for as long as 13 years (3). Rapeseed-mustard (Brassica spp.) is one of the major oilseed crops in India, cultivated on 5.77 million ha with 6.59 million t produced during 2009-2010. Broomrape has been observed in India as a major angiospermic parasitic plant on rapeseed-mustard, tobacco, tomato, and potato. During a field visit to an experimental farm at the Directorate of Rapeseed-Mustard Research, Bharatpur (27°12'N, 77°27'E) in the winter of 2009-2010, symptoms of wilt disease were observed on Orobanche plants, 32.6% of which had wilted completely following root infection. Initial symptoms appeared as a browning of the flowering stalk with wilting. Direct observation of below ground plant parasite tissues revealed a necrosis starting at the radical and advancing to the collar region that shredded later on. Tissue fragments, excised from the internal portions of the diseased tissue, were surface sterilized with 0.1% HgCl2, plated on 2% potato dextrose agar (PDA) adjusted to pH 7.0, and incubated at 22 ± 2°C for 7 days. The colonies that grew on PDA plates produced a bright purple color. Single-spore culturing of the fungus yielded Fusarium solani on the basis of morphological characteristics (2). The Fungal Identification Service, Mycology and Plant Pathology Group, Agharkar Research Institute, Pune, India (Accession No. 2156) confirmed the identity. The pathogenicity of the fungus was tested by inoculating five healthy Orobanche plants that were parasitizing Brassica spp. at the radicle region with 10-ml spore suspensions (2 × 105 conidia/ml of sterile distilled water) derived from 7-day-old cultures of the fungus. Control plants were treated with sterile distilled water. F. solani-inoculated radicles developed typical wilting symptoms within 2 weeks of treatment, while the control as well as the Brassica spp. plants remained healthy. F. solani was reisolated from inoculated wilted plants, thus fulfilling Koch's postulates. To our knowledge, on the basis of the literature, this is the first report from India showing that F. solani infects O. aegyptica on Brassica spp. There are reports of fungi (50 different species) infecting different hosts in Southern Italy, including F. oxysporum and F. solani, which have been found to be pathogenic to O. ramose. The most pathogenic Fusarium isolates significantly increased the number of dead spikes of broomrape (1). Control of Orobanche spp. poses a challenge because of the lack of effective and economic control measures. F. solani thus offers a potentially promising management strategy that should be explored in the future for the control of O. aegyptiaca. References: (1) A. Boari et al. Biol. Control 30:212, 2004. (2) P. E. Nelson et al. Fusarium Species: An Illustrated Manual for Identification. 1st ed. Pennsylvania State University Press, University Park, 1983. (3) M.C. Press et al. Parasitic Plants. Chapman and Hall, London, UK, 1995.

13.
Mol Plant Microbe Interact ; 20(12): 1489-94, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17990956

RESUMO

Full-length cDNAs of the wild-type (wt) Tobacco mosaic virus (TMV) and of the coat protein gene-deleted (DeltaCP) derivative of wt-TMV, under control of the 35S promoter and downstream ribozyme sequence to produce accurate viral transcripts, were transformed to tobacco plants to analyze plant-virus interactions through different stages of plant development. Surprisingly, young wt-TMV transgenics accumulated only very low levels of viral RNA, remained free of symptoms, and were moderately resistant against exogenous inoculations. This early resistance caused significant stress to the plants, as indicated by reduced growth. Approximately 7 to 8 weeks after germination, the resistance was broken and plants developed typical wt-TMV symptoms, with high accumulation of the viral RNAs and proteins. The DeltaCP-TMV plants likewise were initially resistant to the endogenous inoculum and were stunted, although to a lesser extent than the wt-TMV plants. The resistance was broken at the same time as in the wt-TMV plants, but the mutant replicated to much lower levels and produced much milder symptoms than the wt virus. TMV-specific small interfering RNAs as well as increased transgene methylation were detected in the plants only after the resistance break, indicating that the resistance in the young plants was not due to RNA silencing.


Assuntos
Genoma Viral , Nicotiana/virologia , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas/virologia , Vírus do Mosaico do Tabaco/genética , Metilação de DNA , Imunidade Inata , Plantas Geneticamente Modificadas/metabolismo , RNA Viral/metabolismo , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento
14.
Australas Phys Eng Sci Med ; 25(3): 119-23, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12416588

RESUMO

The low energy (30-50 kVp) beams from an intra-operative X-ray source are modelled using a basic analytical model considering just primary beam attenuation and absorption. Spatial dosimetry at such low energies is difficult due to the rapid changes in dose-rate from the radiation source. The purpose of the model was to determine the variation with distance in water of coefficients required for beam dosimetry and to validate beam measurements performed in water of high-gradient dose distributions. The model predicts a change in mean mass-energy absorption coefficient of up to 3 % over the range of clinically-relevant distances in water. Distance-dose distributions (variation in dose with distance in water) for the X-ray source were calculated with the model and found to be in agreement with measurement (at clinically-relevant distances), to within a spatial distance comparable to the dimensions and positional accuracy of the ionization chamber used, and comparable to the expected dosimetric anisotropy of the radiation source. Measured and calculated distance-doses begin to diverge at relatively large distances from the radiation source, which is where dose-rates are so low that detector signal levels are comparable with noise.


Assuntos
Modelos Teóricos , Neoplasias/radioterapia , Radiometria/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Absorção , Simulação por Computador , Humanos , Radiometria/instrumentação , Planejamento da Radioterapia Assistida por Computador/instrumentação , Sensibilidade e Especificidade , Água , Raios X
15.
Biopolymers ; 59(3): 167-79, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11391566

RESUMO

Conformational searches on three closely related pp60(c-src) protein tyrosine kinase inhibitors of varying potencies were performed to determine a structural basis for their activity. The first was a linear peptide (PDNEYAFFQf), the second its 10-membered cyclic analogue, and the third a cyclic analogue with a para carboxyphenylalanine in place of one the F residues. A common backbone conformation with an antiparallel beta-sheet-like geometry capped by similar beta-turns was found for all three peptides, which may be a binding conformation and gives a candidate pharmacophore for further testing. The interaction between some polar side chains and between some of the aromatic rings may be important for maintaining the correct conformation. The differences in potencies of these inhibitors may be attributed to certain thermodynamic and chemical reasons.


Assuntos
Inibidores Enzimáticos/química , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Proteínas Proto-Oncogênicas pp60(c-src)/antagonistas & inibidores , Proteínas Proto-Oncogênicas pp60(c-src)/química , Sequência de Aminoácidos , Simulação por Computador , Inibidores Enzimáticos/farmacologia , Modelos Moleculares , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Conformação Proteica , Software , Relação Estrutura-Atividade
16.
Indian J Clin Biochem ; 15(1): 6-10, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23105230

RESUMO

In this study we have modified DNA by exposing it to ultraviolet light in the presence of hydrogen peroxide. The modified DNA was probed for binding to the antibodies present in the sera of patients suffering from various types of cancer. Higher recognition of modified DNA, as compared to native DNA, by antibodies from cancer patients has got far reaching significance.

18.
J Laryngol Otol ; 112(4): 393-5, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9659508

RESUMO

Ectopic thyroid is an uncommon embryological aberration characterized by the presence of thyroid tissue at a site other than in its usual pretracheal region. Usually it occurs along the path of descent of the developing thyroid primodium from the foramen caecum, commonest being lingual followed by sublingual and in the anterior midline of neck at, or below, the level of the hyoid bone. It is unusual for lingual thyroid to present simultaneously with another ectopic thyroid; reported here are two such cases.


Assuntos
Coristoma/diagnóstico por imagem , Pescoço , Glândula Tireoide , Doenças da Língua/diagnóstico por imagem , Adolescente , Adulto , Coristoma/patologia , Humanos , Masculino , Cintilografia , Doenças da Língua/patologia
19.
Indian J Clin Biochem ; 13(1): 36-40, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23105181

RESUMO

Present study repots changes in serum copper levels (SCL) in various neoplastic diseases undergoing radiotherapy. We estimated SCLs in 140 individuals comprising of 90 previously untreated patients with various malignancies and 50 healthy controls. Patients received radiation in doses of 40-70 Gy in 4-7 weeks. SCLs were again estimated in patients following irradiation. The mean SCL was significantly higher (P<0.001) in cancer patients as compared to healthy controls. It declined significantly (P<0.001) following irradiation. However, it remained significantly higher as compared to healthy controls (P<0.01). Highest fall in SCL was seen in complete clinical responders and least in non-responders to radiation treatment. Serial estimation of SCLs may be useful in the treatment monitoring of the neoplasms undergoing radiation treatment.

20.
J Pak Med Assoc ; 45(7): 180-1, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8523640

RESUMO

Granulocytic sarcoma is an unusual variant of myeloid malignancy most commonly encountered in the course of chronic or acute myeloid leukaemia. Of 60 patients of chronic myeloid leukaemia studied over 21 months, we encountered 6 (10%) cases of granulocytic sarcoma. Four of these had granulocytic sarcoma on their first presentation. All those who were receiving hydroxyurea did not fare well but one who was put on DAT (daunorubicin, cyftosine arabinocide, 6 thioguanine)regimen went into remission with complete disappearance of lesions.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Adolescente , Adulto , Antibióticos Antineoplásicos/uso terapêutico , Antineoplásicos/uso terapêutico , Daunorrubicina/uso terapêutico , Feminino , Humanos , Hidroxiureia/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Infiltração Leucêmica , Masculino , Pessoa de Meia-Idade , Prognóstico
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