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Weeds are one of the key threats in sustaining the productivity of the rice-wheat cropping system in the Indo-Gangetic Plains. The development of sound integrated weed management technologies requires knowledge of mechanisms that influence weed flora composition and weed seedbank dynamics. A long-term study was initiated in 2015 at Patna, Bihar, India to evaluate the effect of seven tillage and crop establishment methods on weed density, weed seedbank composition, and crop productivity in rice-wheat-mungbean rotation. All the treatments included zero-till mungbean after wheat. Tillage and crop establishment methods had differential effects on weed and weed seedbank composition. In rice, zero-till direct-seeded rice recorded 62% lower emergence of Cyperus iria, 82-90% of Echinochloa colona, and 81-83% of total weeds compared to tilled systems, but the system of rice and wheat intensification favoured E. colona. In wheat, the system of wheat intensification favoured the Phalaris minor and Solanum nigrum. Zero-till rice and wheat reduced the seedbank of Trianthema portulacastrum by 95%, and total weed seedbank by 62% compared to the system of rice and wheat intensification. Nearly, 72% of C. iria seeds, 62% of grasses, and 64% of broad-leaved weeds were in 0-15 cm soil layer. Zero-till direct-seeded rice produced a 13% lower rice grain yield than conventional puddled transplanted rice. Compared to the system of wheat intensification, zero-till wheat under triple zero-till systems produced an 11.5% higher grain yield. Managing weed seedbank is a long-term endeavour. The present study revealed that tillage and crop establishment methods influence weed density and diversity. Under zero-till rice-wheat system, rice yield decreases marginally, but the system productivity maintains due to improvement in succeeding wheat yield. This system is also helpful in reducing the weed flora density and soil weed seedbank. Regular monitoring and management of emerging pests such as armyworm (Mythimna separata) are, however, required. The study suggests that the adoption of triple zero-tillage can be a viable option for reducing the weed density and weed seedbank concurrently increasing the system productivity of the rice-wheat-mungbean cropping system in eastern Indo-Gangetic Plains.
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In the eastern Indo-Gangetic Plains (EIGP), conventional rice-wheat system has led to a decline in productivity, input-use efficiency, and profitability. To address these, a four-year field study was conducted to evaluate the performance of tillage and crop establishment (TCE) methods in rice-wheat-greengram rotation. The treatments included: 1) random puddled transplanted rice (RPTR) - conventional-till broadcast wheat (BCW) - zero-till greengram (ZTG); 2) line PTR (LPTR) - conventional-till drill sown wheat (CTW) - ZTG; 3) machine transplanted rice in puddled soil (CTMTR) - zero tillage wheat (ZTW) - ZTG; 4) machine transplanted rice in zero-till wet soil (ZTMTR) - ZTW - ZTG; 5) system of rice intensification (SRI) - system of wheat intensification (SWI) - ZTG; 6) direct-seeded rice (DSR) - ZTW - ZTG; and 7) zero-till DSR - ZTW - ZTG. During the initial two years, conventional rice system (PTR) recorded a 16.2 % higher rice grain yield than DSR system. Whereas in the fourth year, the rice yields under DSR and PTR were comparable. As compared to SRI/SWI, the average wheat yield in ZT system was significantly high, whereas in rice, SRI/SWI system was comparable with CT system. ZTW after non-puddled rice was at par to CTW after PTR. The ZT wheat produced 4.6 % more yield than CT system. DSR production system consumed 6.8 % less water compared to transplanted system. On the system basis, 10.8 % higher net returns were recorded with CA-based system compared to conventional system. The system energy productivity under CA-based production system was 14-36 % higher than PTR-based systems. CA-based system also led to 8-10 % lower global warming potential (GWP) than conventional methods. The current study indicated that as compared to conventional system, a significant gain in productivity, profitability and energy-use efficiency, and reduction in the environmental mitigation are possible with emerging alternative TCE methods. Long-term expansion and further refinement of these technologies in local areas need to be explored for the second green revolution.
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Rice-wheat cropping system (RWCS) is the most important system occupying around 26 M ha spread over the Indo Gangetic Plains in South Asia and China. Many long-term trials were led to assess the agronomic productivity and economic profitability of various combinations of conservation agricultural (CA) practices (zero tillage, residue management and crop establishment) in RWCS of Eastern Indo-Gangetic Plains (EIGP) of India. The purpose of this study was to investigate the best management practices involving different tillage-based crop establishment and residue retention techniques and their contribution to agricultural system sustainability through improvement in soil health by developing soil quality index (SQI). We have used SQI as an instrument based on physical [macro aggregate stability (MAS), available water capacity (AWC) and soil penetration resistance (SPR)], chemical [soil organic carbon (OC), available N, available P and available K] and biological [microbial biomass carbon (MBC), fluorescein diacetate (FDA) and dehydrogenase activity (DHA)] properties of soil, because these are very useful indicators of soil's functions for agronomic productivity and soil fertility. Soil properties like MAS, OC, MBC, FDA and DHA were higher by 47, 18, 56, 48 and 53%, respectively, under ZTDSR-ZTW (T7: Zero-till direct seeded rice - Zero-till wheat) than RPTR-CTW (T1: Random puddled transplanted rice - Conventional till broadcasted wheat), at 0-10 cm. CA based treatment T7 also recorded lower SPR (126 N cm-1). SQI for different treatments were calculated by performing principal component analysis based on the total data set method. The higher system rice equivalent yield of 12.41 t ha-1 was observed at SQI value of 0.90 at 0-10 cm and 0.86 at 10-20 cm in T7. It can be concluded that crop residue retention on the surface with zero tillage is beneficial for the sustainability and productivity of the RWCS in EIGP of India.
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In the context of deteriorating soil health, stagnation of yield in rice-wheat cropping system (RWCS) across Indo- Gangetic plains (IGP) and environmental pollution, a long term field experiment was conducted during 2009-2016 taking four crop scenarios with conservation agriculture (CA), crop intensification and diversified cropping as intervening technology aiming to evaluate the sustainability of the systems. Scenario 1 (S1) represented conventional farmers' practice of growing rice and wheat with summer fallow. In scenario 2 (S2) and scenario 3 (S3), legume crop was taken along with rice and wheat with partial CA and full CA, respectively. Conventional RWCS was replaced with rice-potato + maize- cowpea cropping system with partial CA in scenario 4 (S4). The S3 scenario registered highest total organic carbon (TOC) stock of 47.71 Mg C ha-1 and resulted in significant increase of 14.57% over S1 (Farmer's practice) in 0-30 cm soil depth after 7 years of field trial. The S4 scenario having intensified cropping systems recorded lowest TOC of 39.33 Mg C ha-1 and resulted in significant depletion of 17.56% in C stock with respect to S3 in 0-30 cm soil depth. The TOC enrichment was higher in S2, S3 and S4 scenario in the surface soil (0-10 cm) compared to S1. At lower depth (20-30 cm), the TOC enrichment was significantly higher in S2 (12.82 Mg C ha-1) and S3 (13.10 Mg C ha-1 soil) over S1 scenario. The S2 and S3 scenario recorded highest increased allocation of TOC (3.55 and 6.13 Mg C ha-1) to passive pool over S1. The S2 (15.72 t ha-1), S3 (16.08 t ha-1) and S4 (16.39 t ha-1) scenarios recorded significantly higher system rice equivalent yield over S1 (10.30 t ha-1). Among the scenarios, S3 scenario had greater amount of total soil organic carbon, passive pool of carbon and higher system rice equivalent yield, thus, is considered the best cropping management practice to maintain soil health and food security in the middle IGP.
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The possibility of hydrogen production by a hydrogenase impaired mutant strain of Anabaena variabilis in outdoor culture was studied. A computer-controlled rooftop (outdoor) tubular photobioreactor (4.35 L) was assembled. H(2) production rates by A. variabilis PK84 grown in CO(2) + air in the photobioreactor were measured together with other parameters such as temperature, irradiance, pH, dry biomass weight, and pO(2), and Chl a concentrations during summer months of 1998 and 1999. Efficiencies of light energy bioconversion to H(2) energy and energy accumulated in biomass were calculated. The influence of irradiance, temperature, and mode of cultivation on H(2) production and efficiency of light energy bioconversion were evaluated. The culture produced up to 1.1 L H(2) day(-1) PhBR(-1). The efficiency of light energy to H(2) energy bioconversion on some days was 0.094%. However, the conditions for maximum H(2) photoproduction and for maximum efficiency of light energy to H(2) energy bioconversion were not the same. A. variabilis PK84 could produce hydrogen for prolonged periods (up to 40 days) without injection of fresh inoculum. During this period photobioreactor produced 24.5 L of H(2). Possibilities for increasing the efficiency of light energy conversion are discussed.
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Anabaena/metabolismo , Anabaena/efectos de la radiación , Reactores Biológicos/microbiología , Hidrógeno/metabolismo , Luz , Fotobiología/instrumentación , Aerobiosis/fisiología , Aerobiosis/efectos de la radiación , Anabaena/clasificación , Anabaena/crecimiento & desarrollo , Células Cultivadas , Clima , Cianobacterias/clasificación , Cianobacterias/crecimiento & desarrollo , Cianobacterias/metabolismo , Cianobacterias/efectos de la radiación , Diseño de Equipo , Retroalimentación , Mutación , Oxígeno/metabolismo , Periodicidad , Photobacterium , Fotobiología/métodos , Fotoperiodo , Proyectos Piloto , Protones , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Especificidad de la Especie , Luz Solar , Temperatura , Agua/metabolismoRESUMEN
Bacterial leaf blight caused by the bacterial pathogen Xanthomonas oryzae pv oryzae (Xoo) limits rice yield in all major rice-growing regions of the world, especially in irrigated lowland and rainfed conditions where predisposition factors favor disease development to epidemic proportions. Since bacterial pathogens are difficult to manage, development of host plant resistance is the most effective means of disease management. As many as 24 major genes conferring resistance to various races of the pathogen have been identified and utilized in rice breeding programs. However, large-scale and long-term cultivation of varieties carrying a single gene for resistance resulted in a significant shift in pathogen race frequency with consequent breakdown of resistance in these cultivars. To combat the problem of resistance breakdown, pyramiding of resistance genes into different cultivars is being carried out. Pyramiding of resistance genes is now possible with molecular markers that are developed for individual genes. This review discusses the various bacterial blight resistance genes identified and their corresponding molecular markers developed for breeding durable resistance into modern rice cultivars.
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Cultivations of Aspergillus niger cells in which oxygen was provided through the liquid-phase oxygen supply strategy (which involves the need-based decomposition of H2O2 pulses to yield the necessary oxygen) were studied. Concentrations of H2O2 in the range of 1 to 5 mM were found to be suitable for use in cultivations. The growth rate constant of 0.17 h(-1) obtained in the H2O2-based cultivation, was comparable to that obtained in the cultivation with aeration; however, the maximum cell concentration in the H2O2-based cultivation was 124% of that obtained in cultivation with aeration. Maximum concentrations of catalase, protease and glucose oxidase obtained in the H2O2-based cultivation, were 240%, 172%, and 124% respectively, of those obtained in the cultivation with aeration. Further, the specific enzyme levels (units per gram cell) of catalase and protease obtained in the H2O2-based cultivation were 172% and 156% of those obtained in the cultivation with aeration, whereas, the specific glucose oxidase levels were comparable. In addition, the oxygen profiles inside the pellets ofA. niger during both the modes of oxygen supply were described using mathematical models. Studies to elucidate the mechanism of oxygen availability showed that the decomposition of the H2O2 supplied in the extracellular space occurred intracellularly, as well as extracellularly, to yield oxygen. Also, the proton motive force (PMF) was found to be involved in the process of oxygen availability from H2O2 to A. niger cells.
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Enzimas/metabolismo , Hongos/enzimología , Oxígeno/metabolismo , Aspergillus niger/citología , Aspergillus niger/enzimología , Aspergillus niger/crecimiento & desarrollo , Reactores Biológicos/normas , Catalasa/metabolismo , Medios de Cultivo , Endopeptidasas/metabolismo , Proteínas Fúngicas/metabolismo , Hongos/citología , Hongos/crecimiento & desarrollo , Glucosa Oxidasa/metabolismo , Peróxido de Hidrógeno/farmacocinética , Peróxido de Hidrógeno/toxicidad , Modelos BiológicosRESUMEN
Brush border membrane vesicles (BBMVs) were prepared from the 2nd instar larvae of Helicoverpa armigera. Binding of the activated Cry1Ac of Bacillus thuringiensis (Bt) toxin was shown by immunoblot. A 120-kDa protein was identified as a receptor for the Cry1Ac type delta-endotoxin. The aminopeptidase-N activity of BBMVs was measured as the hydrolysis of L-leucine p-nitroanilide. The specific activity was 35 units/mg protein. The BBMV preparation also showed low level of alkaline phosphatase activity. Zn++ chelating agents 2,2'-dipyridyl and 1,10-phenanthroline inhibited aminopeptidase activity at 10 mM concentration, indicating the presence of zinc-dependent aminopeptidase in the brush border of H. armigera. The aminopeptidase activity was increased with increasing concentration of delta-endotoxin. The purified 120-kDa binding protein was N-terminally sequenced. The first 10-amino-acid sequence showed 60-77% similarity with human cysteine-rich secretory protein-1 precursor, inhibin alpha chain precursor. Salmonella flagellar hook protein and yeast carboxypeptidase S.
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Proteínas Bacterianas/metabolismo , Toxinas Bacterianas , Antígenos CD13/metabolismo , Endotoxinas/metabolismo , Proteínas de Insectos , Lepidópteros/enzimología , Microvellosidades/enzimología , Receptores de Superficie Celular/metabolismo , Secuencia de Aminoácidos , Animales , Toxinas de Bacillus thuringiensis , Antígenos CD13/química , Proteínas Hemolisinas , Humanos , Datos de Secuencia MolecularRESUMEN
Hydrogen production by autotrophic, vanadium-grown cells of Anabaena variabilis PK84, a cyanobacterial mutant impaired in the utilization of molecular hydrogen, has been studied under simulated outdoor conditions. The cyanobacterium was cultivated in an automated helical tubular photobioreactor (4.35 L) under air containing 2% CO(2), with alternating 12-h light (36 degrees C) and 12-h dark (14 degrees to 30 degrees C) periods. A. variabilis steadily produced H(2) directly in the photobioreactor during continuous cultivation for 2.5 months. The maximum H(2) production by the continuously aerated culture under light of 332 microE. s(-1). m(-2) was 230 mL per 12-h light period per photobioreactor and was observed at a growth density corresponding to 3.6 to 4.6 microgram Chl a. mL(-1) (1.2 to 1.6 mg dry weight. mL(-1)). Replacement of air with an argon atmosphere enhanced H(2) evolution by a factor of 2. This stimulatory effect was caused mainly by N(2) deprivation in the cell suspension. A short-term decrease of the CO(2) concentration in the air suppressed H(2) evolution. Anoxygenic conditions over the dark periods had a negative effect on H(2) production. The peculiarity of hydrogen production and some physiological characteristics of A. variabilis PK84 during cultivation in the photobioreactor under a light-dark regime are investigated.
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Anabaena/metabolismo , Reactores Biológicos , Biotecnología/métodos , Hidrógeno/metabolismo , Aire , Anabaena/citología , Argón , Adhesión Bacteriana , Dióxido de Carbono , Oscuridad , Concentración de Iones de Hidrógeno , Iluminación , Técnicas Microbiológicas , Oxígeno , Fotoperiodo , TemperaturaRESUMEN
Hydrogen production by Anabaena variabilis ATCC 29413 and of its mutant PK84, grown in batch cultures, was studied in a photobioreactor. The highest volumetric H(2) production rates of native and mutant strains were found in cultures grown at gradually increased irradiation. The native strain evolved H(2) only under an argon atmosphere with the actual rate as high as the potential rate (measured in small vials under optimal conditions). In this case 61% of oxygenic photosynthesis was used for H(2) production. In contrast the mutant PK84 produced H(2) during growth under CO(2)-enriched air. Under these conditions at the maximum rate of H(2) production (10 mL h(-1) L(-1)), 13% of oxygenic photosynthesis was used for H(2) production and the actual H(2) production was only 33% of the potential. Under an atmosphere of 98% argon + 2% CO(2) actual H(2) production by mutant PK84 was 85% of the potential rate and 66% of oxygenic photosynthesis was used for H(2) production. Hydrogen production under argon + CO(2) by the mutant was strictly light-dependent with saturation at about 300 microE m(-2) s(-1). However, the rate of photosynthesis was not saturated at this irradiation. At limiting light intensities (below 250 microE m(-2) s(-1)) 33-58% of photosynthesis was used for H(2) production. Hydrogen evolution by PK84 under air + 2% CO(2) was also stimulated by light; but was not saturated at 332 microE m(-2) s(-1) and did not cease completely in darkness. The rate of oxygen photoevolution was also not saturated. A mechanism for increasing cyanobacterial hydrogen production is proposed.
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Anabaena/genética , Anabaena/metabolismo , Hidrógeno/metabolismo , Argón , Reactores Biológicos , Dióxido de Carbono/metabolismo , División Celular , Luz , Mutación , Nitrogenasa/metabolismo , Oxígeno/metabolismo , FotobiologíaRESUMEN
The effectiveness of radiotherapy in the treatment of malignant tumors in the head and neck, thorasic and upper abdominal regions is frequently limited by the tolerance of the spinal cord. Therefore knowledge of the factors that influence the tolerance of the spinal cord to radiation is of the upmost important. Safe limits for irradiation of the spinal cord determined in a number of clinical studies is on the conservative side from the point of view of tumor control probability. The bioeffect of a physical dose takes into account the treatment variables and the radiobiological characteristics of the relevant tissue; hence deciding spinal cord tolerance on the basis of bioeffect models would be better approach. The aim of the present study was to analyze the relationship of the prognostic factors with percentage incidence of spinal cord myelitis and to arrive at a spinal cord tolerance bioeffect dose TDF and ERD for optimum incidence of radiation myelitis.
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Mielitis/radioterapia , Fraccionamiento de la Dosis de Radiación , Humanos , Incidencia , India/epidemiología , Mielitis/epidemiología , PronósticoRESUMEN
PURPOSE: To see if changes in tumor/blood glutathione (GSH) levels after one fraction of radiotherapy can be correlated with the treatment response in patients with carcinoma of the uterine cervix. METHODS AND MATERIALS: The study was done on 45 patients with squamous cell carcinoma of the uterine cervix, FIGO Stages IIB (17 patients) and IIIB (28 patients). Stage IIB patients received 35 Gy of cobalt-60 external radiotherapy (RT) in 16 fractions over 4 weeks with a concurrent high-dose-rate intracavitary dose of 8.5 Gy to point A once a week. Stage IIIB patients were given 45 Gy of RT in 20 fractions over 5 weeks, followed by two doses of intracavitary therapy once a week. Blood and tumor samples were collected before and after one dose of RT and GSH was estimated. Tumor response was assessed clinically at 1 month after treatment. RESULTS: Glutathione levels in both blood and tumor showed a significant decrease after one fraction of RT, but the degree of decrease varied among patients. There was a good correlation between the extent of GSH decrease and the tumor response. All patients who had complete response (CR) (seven Stage IIB and eight Stage IIIB) showed > or =70% decrease in both tumor and blood GSH, while those who had <50% regression (NR) (five Stage IIB and 13 Stage IIIB) showed <50% decrease in GSH. The partial responders recorded an intermediate level (50-70%) of depletion in blood and tumor GSH. CONCLUSIONS: The results indicate that the changes in tumor/blood GSH levels after one fraction of RT could serve as an index of tumor response to therapy and may help in identifying radioresistant tumors, at least in the case of cervix carcinoma.
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Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Glutatión/efectos de la radiación , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/radioterapia , Biomarcadores/sangre , Carcinoma de Células Escamosas/patología , Femenino , Glutatión/metabolismo , Humanos , Estadificación de Neoplasias , Neoplasias del Cuello Uterino/patologíaRESUMEN
The effect of salinity and osmotic stress on protein synthesis was studied in cowpea Rhizobium 4a. Osmotic component of salinity stress has been shown to induce ten proteins in a salt tolerant/osmosensitive cowpea Rhizobium. 4a (groundnut isolate). Of these seven polypeptides were induced only by salt/osmotic stress while two were induced by heat shock. The results demonstrate a commonality as well as stress specificity of protein synthesis regulation.
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Proteínas de Choque Térmico/química , Ósmosis/fisiología , Rhizobium/metabolismo , Sales (Química)/farmacología , Arachis/microbiología , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , División Celular/efectos de los fármacos , Electroforesis en Gel de Poliacrilamida , Proteínas de Choque Térmico/biosíntesis , Proteínas de Choque Térmico/metabolismo , Cloruro de Potasio/farmacología , Rhizobium/química , Cloruro de Sodio/farmacología , Sacarosa/farmacologíaRESUMEN
Seven new water-soluble cationic complexes of general formula [Pt(2-pyc)(N-N)]+ (where N-N is 2NH3, ethylenediamine (en), 1,2-diaminopropane (1,2-dap), 1,3-diaminopropane (1,3-dap), (+/-) trans-1,2-diaminocyclohaxane (dach), 2,2'-dipyridylamine (dpa) or 1,10-phenanthroline (phen), and 2-pyridinecarboxylate anion) have been prepared. These complexes have been characterized by conductance measurements, and by ultraviolet-visible, infrared (IR), and 1H nuclear magnetic resonance (NMR) spectroscopy. The COSY (correlated spectroscopy) spectra of [Pt(2-pyc)(dpa)]+ and [Pt(2-pys)(dpa)]+ further support the structures of the above complexes with three nitrogen and one oxygen donor atoms in the first coordination sphere of platinum(II) with 1,2-diamine or alpha-diimine and 2-pyridinecarboxylate anion behaving as bidentate ligands. One of the compounds, [Pt(2-pyc)(dpa)]Cl, also shows a birefringence property in water. These compounds inhibit the growth of P388 lymphocytic leukemia cells. [Pt(2-pyc)(dpa)]+ shows I.D.50 value comparable to cisplatin. However, six other complexes show higher I.D.50 values than cisplatin. In addition, the inhibition studies also suggest that their target is DNA. Therefore, the interactions of four of the above complexes with calf thymus DNA have been studied by ultraviolet and fluorescence spectral methods. These studies suggest that [Pt(2-pyc)(NH3)2]+ and [Pt(2-pyc)(1,2-dap)+ bind to DNA by noncovalent interactions. On the other hand, [Pt(2-pyc)(dpa)]+ and [Pt(2-pyc)(phen)]+ bind to DNA by covalent monofunctional binding. The latter two complexes have also been interacted with PUC19 DNA. The gel electrophoresis studies of these interactions suggest that these complexes bind to DNA, and this binding leads to a conformational change in DNA.
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Antineoplásicos/síntesis química , Ácidos Carboxílicos/química , ADN/química , Compuestos Organometálicos/síntesis química , Platino (Metal)/química , Piridinas/química , Aniones , Antineoplásicos/análisis , Antineoplásicos/farmacología , Diaminas/química , Diseño de Fármacos , Iminas/química , Leucemia Linfoide/tratamiento farmacológico , Compuestos Organometálicos/análisis , Compuestos Organometálicos/farmacología , Espectrofotometría/métodos , Relación Estructura-Actividad , Células Tumorales CultivadasRESUMEN
The production of beta-glucosidase by Aspergillus terreus was investigated in liquid shake cultures. Enzyme production was maximum on the 7th day of growth (2.18 U/ml) with the initial pH of the medium in the range of 4.0-5.5. Cellulose (Sigmacell Type 100) at 1.0% (wt/vol) gave maximum beta-glucosidase activity among the various soluble and insoluble carbon sources tested. Potassium nitrate was a suitable nitrogen source for enzyme production. Triton X-100 at 0.15% (vol/vol) increased the enzyme levels of A. terreus. The test fungal strain showed an ability to ferment glucose to ethanol.
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Aspergillus/enzimología , beta-Glucosidasa/biosíntesis , Aspergillus/crecimiento & desarrollo , Aspergillus/metabolismo , Biotecnología , Medios de Cultivo , Fermentación , Concentración de Iones de Hidrógeno , Nitrógeno/metabolismo , Especificidad por Sustrato , Tensoactivos/farmacología , beta-Glucosidasa/metabolismoRESUMEN
Anabaena azollae (AS-DS), isolated from Azolla filiculoides and grown in nitrogen-free medium, was immobilized in 5-mm-cube polyvinyl foam pieces and incorporated into a photobioreactor system for the production of NH3. NH3 was produced continuously and in significant amounts. Benlate (methyl-1-butyl-carbamoyl)-2-benzimidazole carbamate at 5 ppm and L-methionine-D,L-sulphoximine at 50 µM stimulated NH3 production continuously for a period of 1 week.
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Southern yellow pine (softwood) and maple (hardwood) wood decayed for 12 weeks by Antrodiella sp. RK1 had average weight losses of 20 and 19%, respectively, and approximately 34 to 35% lignin loss. The ratio of percentage lignin loss to glucose loss was 3.6 and 2.7 for softwood and hardwood, respectively. There was negligible loss of other wood sugars such as xylose, arabinose, galactose and mannose. Scanning electron microscopy revealed the presence of erosion troughs and bore holes in decayed samples of both softwood and hardwood. Secondary walls were void of lignin, middle lamella and cell corners were extensively decayed. Ca(2+) crystals were abundantly present in the areas of decay. Transmission electron micrographs revealed the presence of hyphal sheath and growth of hyphae directly through the cell corners.
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The endoglucanases of Penicillium funiculosum were analyzed for the presence of multiple forms using a modified version of the Congo red method. Postelectrophoretic slab gels were directly incubated in a solution of carboxymethylcellulose for a period as short as 15 min and then the activities were visualized by staining with Congo red. Ten distinct bands of clearances were obtained indicating the presence of at least as many multiple forms.
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Resinas Acrílicas , Celulasa/análisis , Proteínas Fúngicas/análisis , Isoenzimas/análisis , Penicillium/enzimología , Rojo Congo , Desnaturalización Proteica , Reproducibilidad de los Resultados , Coloración y Etiquetado/métodosRESUMEN
A prospective clinical and histopathological study of 103 patients with lymphomas is reported. Of these, 72 (69.9%) had non-Hodgkin's lymphoma (NHL) and 31 (30.1%) had Hodgkin's lymphoma (HL). The median age at presentation was 34 and 43 years for Hodgkin's and non-Hodgkin's lymphoma respectively, which is lower than that seen in the West. Fever and superficial lymphadenopathy were the commonest presenting features and 'B' symptoms were present in over 60% of both groups. Seventy-five per cent of NHL and 64.5% of HL presented in stages III and IV of the disease.