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1.
Biopolymers ; 112(3): e23418, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33480035

RESUMO

A boron loaded super-absorbent hydrogel (BLSAH) was developed through in situ incorporation of boron (B) in a guar gum-based hydrogel and characterized with FTIR, thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), and swelling studies, showing maximum absorption up to 356 g/g. The release pattern of B from the BLSAH and its kinetics was studied in water as well as soil. The B release pattern of the BLSAH was also compared with the commercial B fertilizer, boronated single super phosphate (bSSP). The BLSAH, following the Fickian mechanism, released 38% B, as compared with 51% of the bSSP, during the incubation period of 30 days in soil. The half-life period for the BLSAH (96.25 days) in soil was almost triple that of the bSSP's half-life (33.32 days), which is indicative of the slow and controlled release of B from the BLSAH. Thus, owing to its sustained nutrient release ability, the synthesized BLSAH exhibited wide potential for applications in agriculture sector.


Assuntos
Boro/metabolismo , Hidrogéis/química , Micronutrientes/química , Agricultura , Galactanos/química , Meia-Vida , Cinética , Mananas/química , Micronutrientes/metabolismo , Gomas Vegetais/química , Solo/química , Água/química
2.
Carbohydr Polym ; 185: 169-178, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29421054

RESUMO

The novel hydrogels were synthesized by grafting guar gum with acrylic acid and cross-linking with ethylene glycol di methacrylic acid (EGDMA). The synthesis of hydrogel was confirmed by characterization through 13C NMR, FTIR spectroscopy, SEM micrography, thermo-gravimetric analysis and water absorption studies under different solutions. Synthesized hydrogel (GG-AA-EGDMA) was confirmed to be biodegradable with half-life period of 77 days through soil burial biodegradation studies. The effects of hydrogel treatment on soil were evaluated by studying various physico-chemical properties of soil like bulk density, porosity, water absorption and retention capacity etc. The hydrogel which could absorb up to 800 ml water per gram, after addition to soil, improved its porosity, moisture absorption and retention capacity significantly. Water holding capacity of water increased up to 54% of its original and porosity also increased up to 9% of its original. The synthesized hydrogel revealed tremendous potential as soil conditioning material for agricultural applications.

3.
Carbohydr Polym ; 168: 274-281, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28457450

RESUMO

With the aim to explore new adsorbents for water purification, guar gum based hydrogels were synthesized by cross-linking with borax at different percentage. The cross-linking was confirmed through characterization by FTIR spectroscopy, SEM morphology, thermal studies and water absorption capacity. To examine the adsorption/absorption performance of different grades of hydrogels, their flocculation efficiency was studied in kaolin suspension at different pH by standard jar test procedure. The flocculation efficiency of the test materials was compared with the commercially used coagulant, alum and also residues of Al and K left in the treated water were comparatively studied. The synthesized hydrogels were also tested for their efficiency of removing Aniline Blue dye by UV-vis spectrophotometer study. The best grade hydrogel outperformed alum, at extremely low concentration and also showed dye removing efficiency up to 94%. The single step synthesized green products thus exhibited great potential as water purifying agents.

4.
Int J Biol Macromol ; 88: 361-72, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27044346

RESUMO

Guar gum is the powdered endosperm of the seeds of the Cyamopsis tetragonolobus which is a leguminous crop. The endosperm contains a complex polysaccharide called galactomannan, which is a polymer of d-galactose and d-mannose. This hydroxyl group rich polymer when added to water forms hydrogen bonding imparting significant viscosity and thickening to the solution. Due to its thickening, emulsifying, binding and gelling properties, quick solubility in cold water, wide pH stability, film forming ability and biodegradability, it finds applications in large number of industries. In last few decades a lot of research has been done on guar gum to fit it into particular application, as such or by its structural modifications. This review gives an overview of the nature, chemistry and properties of guar gum and discusses recent developments in its modifications and applications in major industries like hydraulic fracturing, explosives, food, agriculture, textile, paper, cosmetics, bioremediation, drug delivery, medical and pharmaceuticals. This article would help researchers engaged in biopolymer area and other end-users who want to begin research in natural polysaccharides.


Assuntos
Galactanos/química , Mananas/química , Gomas Vegetais/química , Polissacarídeos/química , Cyamopsis/química , Substâncias Explosivas/química , Indústria Alimentícia , Galactose/análogos & derivados , Humanos , Fraturamento Hidráulico , Ligação de Hidrogênio , Solubilidade , Têxteis , Viscosidade
5.
Indian J Pharm Sci ; 75(3): 368-72, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-24082356

RESUMO

The present study reports physicochemical characterization and antioxidant activity of essential oils extracted from guggul (Commiphora wightii) exudates collected from different places in Madhya Pradesh, India. The guggul exudates were hydrodistilled for 3-4 h in Clevenger apparatus. The oil obtained was dried over anhydrous Na2SO4 and stored at 4° until testing. Before extraction of oils from the exudates, their % moisture and tristimulus values of the colors namely L (white-black), a (green-red) and b (blue-yellow) were determined. Physicochemical characterization of the extracted oils was carried out to determine their solubility, yield%, acid value (mg/KOH/g), saponification value (mg/KOH/g), ester value, iodine value (g/g), peroxide value (mEq/kg) and Fourier transformed infrared analyses. The storage-effect on the % moisture and tristimulus values of the colors of guggul exudates as also the % oil yield and physicochemical parameters of the essential oils extracted from them, were studied using three different packaging materials viz., local plastic, low density polyethylene (200 G) and high density polyethylene (200 G). The antioxidant potential of extracted oils was evaluated by free radical scavenging activity using 1,1-diphenyl-2-picryl hydrazyl assay.

6.
Indian J Pharm Sci ; 74(5): 422-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23716870

RESUMO

The antihyperlipidemic activity of resinoids of guggul (Commiphora mukul/Commiphora wightii), belonging to family Burseraceae (Genus: Commiphora), collected from different parts of India (Gujarat, Madhya Pradesh and Rajasthan), was studied on cholesterol-rich high fat diet-induced model of hyperlipidemia in rats. The resinoids of these exudates were prepared in ethyl acetate and ethyl alcohol. The physicochemical characterization of these resinoids was carried out to determine their appearance, %yield, %moisture, %ash, acid value (mg/KOH/g), saponification value (mg/KOH/g), ester value and iodine value (g/g). Antihyperlipidemic study was carried out on all resinoids in high fat diet induced model of hyperlipidemia in Wistar albino rats. The result demonstrated that the resinoids of exudates of Commiphora wightii and Commiphora mukul, collected from Gujarat and extracted in ethyl acetate, and the resinoids of exudates of Commiphora mukul, collected from Madhya Pradesh and extracted in ethyl acetate, possessed significantly higher antihyperlipidemic activity compared with other resinoids, which may be due to regional/geographical variations.

7.
Indian J Pharm Sci ; 73(3): 255-61, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-22457547

RESUMO

The resin of Boswellia species has been used as incense in religious and cultural ceremonies and in medicines since time immemorial. Boswellia serrata (Salai/Salai guggul), is a moderate to large sized branching tree of family Burseraceae (Genus Boswellia), grows in dry mountainous regions of India, Northern Africa and Middle East. Oleo gum-resin is tapped from the incision made on the trunk of the tree and is then stored in specially made bamboo basket for removal of oil content and getting the resin solidified. After processing, the gum-resin is then graded according to its flavour, colour, shape and size. In India, the States of Andhra Pradesh, Gujarat, Madhya Pradesh, Jharkhand and Chhattisgarh are the main source of Boswellia serrata. Regionally, it is also known by different names. The oleo gum-resins contain 30-60% resin, 5-10% essential oils, which are soluble in the organic solvents, and the rest is made up of polysaccharides. Gum-resin extracts of Boswellia serrata have been traditionally used in folk medicine for centuries to treat various chronic inflammatory diseases. The resinous part of Boswellia serrata possesses monoterpenes, diterpenes, triterpenes, tetracyclic triterpenic acids and four major pentacyclic triterpenic acids i.e. ß-boswellic acid, acetyl-ß-boswellic acid, 11-keto-ß-boswellic acid and acetyl-11-keto-ß-boswellic acid, responsible for inhibition of pro-inflammatory enzymes. Out of these four boswellic acids, acetyl-11-keto-ß-boswellic acid is the most potent inhibitor of 5-lipoxygenase, an enzyme responsible for inflammation.

8.
Indian J Pharm Sci ; 72(1): 12-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20582184

RESUMO

Ever since the development of Hybridoma Technology in 1975 by Kohler and Milstein, our vision for antibodies as tools for research for prevention, detection and treatment of diseases, vaccine production, antigenic characterization of pathogens and in the study of genetic regulation of immune responses and disease susceptibility has been revolutionized. The monoclonal antibodies being directed against single epitopes are homogeneous, highly specific and can be produced in unlimited quantities. In animal disease diagnosis, they are very useful for identification and antigenic characterization of pathogens. Monoclonal antibodies have tremendous applications in the field of diagnostics, therapeutics and targeted drug delivery systems, not only for infectious diseases caused by bacteria, viruses and protozoa but also for cancer, metabolic and hormonal disorders. They are also used in the diagnosis of lymphoid and myeloid malignancies, tissue typing, enzyme linked immunosorbent assay, radio immunoassay, serotyping of microorganisms, immunological intervention with passive antibody, antiidiotype inhibition, or magic bullet therapy with cytotoxic agents coupled with anti mouse specific antibody. Recombinant deoxyribonucleic acid technology through genetic engineering has successfully led to the possibility of reconstruction of monoclonal antibodies viz. chimeric antibodies, humanized antibodies and complementarily determining region grafted antibodies and their enormous therapeutic use.

9.
Vet Res Commun ; 26(3): 179-88, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12090290

RESUMO

A panel of 38 monoclonal antibodies (MAbs) that react with outer membrane proteins (OMPs) of Salmonella enteritidis was produced. On the basis of their binding pattern in ELISA, the MAbs were divided into three groups. The first group, consisting of 15 MAbs, was found to be Salmonella-specific as they did not cross-react with Escherichia coli or Pasteurella multocida. The second group of 15 MAbs cross-reacted with E. coli but not with P. multocida, reflecting the closer antigenic relationship of E. coli with Salmonella. The third group of 8 MAbs cross-reacted with both E. coli and P. multocida, indicating that the antigenic determinants identified by these MAbs are conserved in all the three genera. The antigenic relationship of the Salmonella serovars (S. enteritidis, S. gallinarum, S. typhimurium, S. dublin, S. agona, S. indiana and S. choleraesuis) was studied using OMPs prepared from them and the anti-S. enteritidis MAbs. Three MAbs appeared to be specific for S. enteritidis as they did not cross-react with any of the other Salmonella serovars. Twelve of the 38 MAbs cross-reacted with all the serovars tested. Six of these were specific to the Salmonella genus as they did not cross-react with any of the other Gram-negative bacteria tested. The reactivity pattern of the other MAbs indicated that S. gallinarum was antigenically close to S. enteritidis, followed in order by S. dublin, S. agona, S. typhimurium and S. indiana, whereas S. choleraesuis seemed to be antigenically quite distant from S. enteritidis.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Bactérias/imunologia , Salmonella enteritidis/imunologia , Salmonella/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Especificidade de Anticorpos , Variação Antigênica/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Western Blotting , Ensaio de Imunoadsorção Enzimática , Camundongos , Camundongos Endogâmicos BALB C , Salmonella/classificação , Infecções por Salmonella/imunologia
10.
Vasc Surg ; 35(3): 235-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11452353

RESUMO

Buerger's disease is a recurrent, inflammatory, segmental, vasoocclusive disease. Typically, the disease affects middle-aged male smokers and involves arteries and veins of extremities. Buerger's disease involving visceral vessels is rare. The authors report on a 51-year-old man with peripheral arterial disease and recurrent intestinal ischemia secondary to Buerger's disease. Clinical and histopathologic features of this case illustrate the life-threatening nature of visceral involvement in Buerger's disease.


Assuntos
Intestinos/irrigação sanguínea , Isquemia/diagnóstico , Isquemia/etiologia , Artéria Mesentérica Superior/patologia , Tromboangiite Obliterante/complicações , Humanos , Masculino , Pessoa de Meia-Idade
13.
Int J Biol Macromol ; 26(1): 17-21, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10520952

RESUMO

Few dehydrophenylalanine (deltaPhe) analogues (X-deltaPhe-Phe-Gly-X1, X = Ac-; Boc-; Z-; X1 = OMe; OH; ONH2) of virus replication inhibiting peptide (Z-D-Phe-Phe-Gly) were synthesized, and their solution conformations were investigated by 1H NMR, UV and circular dichroism (CD) spectroscopy. Homogeneity of these analogues was also assessed by reverse phase-high performance liquid chromatography (RP-HPLC) using water-acetonitrile gradients.


Assuntos
Oligopeptídeos/química , Peptídeos/síntese química , Fenilalanina/análogos & derivados , Sequência de Aminoácidos , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Peptídeos/isolamento & purificação , Fenilalanina/química , Espectrofotometria Ultravioleta
14.
Vet Res Commun ; 23(2): 81-90, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10359152

RESUMO

The immunogenicity of a sonicated extract (SE) and of outer membrane proteins (OMP) of Salmonella enteritidis was tested in birds of about 8 weeks of age. The dose, route of vaccination and the adjuvant used varied in different groups of birds. Two vaccine doses with or without adjuvant were given parenterally or orally 3 weeks apart. OMP vaccines gave significantly higher antibody titres than SE vaccines, as indicated by ELISA. The vaccines adjuvanted with oil produced higher antibody titres than those without any adjuvant. A dose of 1 mg of vaccine produced higher antibody titres than 0.5 mg of vaccine. Adjuvanted vaccine given subcutaneously elicited higher antibody responses than oral vaccines given without adjuvant. The birds were challenged with virulent S. enteritidis organisms at the end of the second week after a booster dose. None of the birds given 1 mg of OMP vaccine subcutaneously shed the organisms when tested by culturing cloacal swabs, although a few birds vaccinated with 0.5 mg of OMP vaccine did so. In general, adjuvanted OMP vaccines gave better protection than SE vaccines.


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas , Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/prevenção & controle , Salmonella enteritidis/imunologia , Animais , Anticorpos Antibacterianos/biossíntese , Galinhas , Ensaio de Imunoadsorção Enzimática/veterinária
15.
Int J Biol Macromol ; 19(2): 99-102, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8842772

RESUMO

Conformation of chemically synthesized tetrapeptide tuftsin, an important immunomodulator, with the sequence Thr-Lys-Pro-Arg-OH has been studied in aqueous solution as well as in a number of organic solvents viz. trifluoroethanol (TFE), methanol and dioxane by circular dichroism (CD) spectroscopy which reveals preferential occurrence of mixture of random coil and beta-turns, that has already been predicted as bioactive conformation of this peptide.


Assuntos
Tuftsina/química , Dicroísmo Circular , Metanol , Conformação Proteica , Soluções , Água
16.
Indian J Biochem Biophys ; 32(1): 55-9, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7665196

RESUMO

A protocol on reversed phase high performance liquid chromatogrpahy (RP-HPLC) using water-acetonitrile gradients under lesser stringent conditions, has been devised to obtain highly purified tuftsin in bulk amount. The protocol was also tested for two different preparations of tuftsin to yield identical quality of peptide.


Assuntos
Cromatografia Líquida de Alta Pressão , Tuftsina/isolamento & purificação , Sequência de Aminoácidos , Dados de Sequência Molecular , Tuftsina/síntese química
17.
Int J Biol Macromol ; 16(5): 259-63, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7534472

RESUMO

A T-cell stimulating peptide Val-Gln-Gly-Glu-Glu-Ser-Asn-Asp-Lys-OH, the 163-171 fragment epitope of interleukin-1 beta (IL-1 beta), has been synthesized in solution phase and purified by reverse-phase high-performance liquid chromatography (RP-HPLC). The backbone conformation of the synthetic fragment, investigated in aqueous solution by circular dichroism (CD) spectroscopy, is qualitatively a mixture of beta-turns and random coil. Quantification of the CD spectra revealed the presence of a 9% beta-turn fraction in water at pH 7.0, suggesting the occurrence of the conformation for the epitope fragment in aqueous solution necessary for T-cell stimulation and antigenicity. Concomitant changes in CD spectra were observed with increases in the trifluoroethanol (TFE) concentration in water, and the beta-turn fraction in peptide increased to 28% at a concentration of 90% TFE. This helicogenic solvent, as well as other solvents such as methanol, acetonitrile and dioxane (all favouring an ordered structure in peptides), failed to induce any alpha-helical conformation in the IL-1 beta (163-171) fragment, and CD spectra were attributed to only beta-turn ordered structure. This beta-turn structure has also been found to be a theoretically preferred conformation using Chou-Fasman proclivity data and is in accordance with the presence of an all-beta-globular conformation for its parent molecule IL-1 beta. Thus, the beta-turn conformation is probably involved in retention of T-cell stimulation activity in this synthetic epitope.


Assuntos
Dicroísmo Circular , Interleucina-1/química , Fragmentos de Peptídeos/química , Sequência de Aminoácidos , Epitopos/química , Interleucina-1/síntese química , Interleucina-1/farmacologia , Interleucina-1beta , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/farmacologia , Conformação Proteica , Relação Estrutura-Atividade , Linfócitos T/efeitos dos fármacos
18.
Acta Obstet Gynecol Scand ; 68(7): 669-70, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2631536

RESUMO

A woman with an endodermal sinus tumor of the ovary stage IV obtained a short but complete remission after treatment with vinblastine, bleomycin and standard dose cisplatin. A second complete remission for 42+ months was obtained with a regimen of vinblastine, bleomycin, etoposide, and high dose cisplatin. This result suggests a dose-response relationship for cisplatin in ovarian germ cell tumors.


Assuntos
Cisplatino/administração & dosagem , Mesonefroma/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Humanos
19.
Cancer ; 62(4): 686-90, 1988 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-3135110

RESUMO

A 29-year-old man with metastatic extraadrenal pheochromocytoma developed paraplegia which reversed completely after megavoltage irradiation of the dorsolumbar spine. Later, treated with cyclophosphamide, vincristine, and dacarbazine, he had a temporary decrease in plasma norepinephrine concentration, a partial recalcification of bone lesions, and a decrease in the need for antihypertensive treatment for 12 months. Irradiation and combination chemotherapy should be evaluated further in the management of malignant pheochromocytoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/secundário , Feocromocitoma/secundário , Radioterapia de Alta Energia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/radioterapia , Terapia Combinada , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Norepinefrina/sangue , Paraplegia/etiologia , Feocromocitoma/tratamento farmacológico , Feocromocitoma/radioterapia
20.
Acta Haematol ; 77(3): 180-2, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3113160

RESUMO

A 29-year-old man with acute myelomonocytic leukemia had an initial leukocyte count of 192 X 10(9) cells/l and 84% blasts. During the initial treatment with hydroxyurea, 1 g/m2 orally tid, he developed pulmonary leukostasis which responded rapidly to whole-lung radiation with 1.5 Gy in one fraction. Pulmonary leukostasis in hyperleukocytotic AML is an oncologic emergency demanding rapid intervention. The combined treatment with chemotherapy and radiation appears useful.


Assuntos
Hidroxiureia/uso terapêutico , Leucemia Mieloide Aguda/complicações , Pneumopatias/terapia , Radioterapia de Alta Energia , Adulto , Terapia Combinada , Humanos , Pneumopatias/tratamento farmacológico , Pneumopatias/etiologia , Masculino
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