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91.
Naturally occurring biological entities with extractable and tunable structural and functional characteristics, along with therapeutic attributes, are of supreme interest for strengthening the twenty-first-century biomedical settings. Irrespective of ongoing technological and clinical advancement, traditional medicinal practices to address and manage inflammatory bowel disease (IBD) are inefficient and the effect of the administered therapeutic cues is limited. The reasonable immune response or invasion should also be circumvented for successful clinical translation of engineered cues as highly efficient and robust bioactive entities. In this context, research is underway worldwide, and researchers have redirected or regained their interests in valorizing the naturally occurring biological entities/resources, for example, algal biome so-called “treasure of untouched or underexploited sources”. Algal biome from the marine environment is an immense source of excellence that has also been demonstrated as a source of bioactive compounds with unique chemical, structural, and functional features. Moreover, the molecular modeling and synthesis of new drugs based on marine-derived therapeutic and biological cues can show greater efficacy and specificity for the therapeutics. Herein, an effort has been made to cover the existing literature gap on the exploitation of naturally occurring biological entities/resources to address and efficiently manage IBD. Following a brief background study, a focus was given to design characteristics, performance evaluation of engineered cues, and point-of-care IBD therapeutics of diverse bioactive compounds from the algal biome. Noteworthy potentialities of marine-derived biologically active compounds have also been spotlighted to underlying the impact role of bio-active elements with the related pathways. The current review is also focused on the applied standpoint and clinical translation of marine-derived bioactive compounds. Furthermore, a detailed overview of clinical applications and future perspectives are also given in this review.  相似文献   
92.
Silicon has the potential to improve drought tolerance in crops. Seeds primed with silicon were used in the present study to explore its potential benefit to withstand water stress. Seeds of two wheat varieties, NARC-2009 and Chakwal-50, were sown in pots after priming with distilled water and different concentrations (0.5%, 1.0% and 1.5%) of silicon sources (silicic acid, sodium silicate and silica gel) at PMAS, Arid Agriculture University, Rawalpindi. Maximum silicon uptake at three-leaf stage (0.028 µg g?1 dry weight (DW)), anthesis (0.072 µg g?1 DW) and maturity (0.103 µg g?1 DW) was recorded for silica gel. Silicon uptake increased significantly in response to increase in Si concentration from 0.5% to 1.5%. Leaf membrane stability index, epicuticular wax, relative water content and proline remained maximum – 78.90%, 2.6 mg g?1 DW, 83.88% and 54.90 µg g?1 – for silica gel treatments compared with others. Silica gel with 1.5% silicon concentration resulted in maximum spike length (14.3 cm), biological yield (7.63 g pot?1), hundred-grain weight (3.97 g pot?1) and grain yield (2.46 g pot?1). Based on the study outcomes, it is concluded that silica gel might be a good priming option with 1.5% silicon concentration to establish plant under drought stress.  相似文献   
93.
Corn containing genetically engineered plasmid DNA encoding an Escherichia coli glutamate dehydrogenase (gdhA) was fed to 19-d-old weanling swine to trace the digestive fate of the transgenic DNA. Eight pens of 8 pigs were fed a commercial (nongdhA) starter for 2 wk. One pig was randomly selected from each pen for 0-h control samples. The remaining 56 pigs were transitioned onto a corn-soybean meal diet and fed a diet containing 58% gdhA corn for approximately 1 wk; immediately thereafter, liver, 10th rib muscle, white blood cells, and plasma from the hepatic portal vein and ingesta from the stomach, distal ileum, and large intestine were collected. The DNA was extracted and the concentration determined via spectrophotometry. Polymerase chain reaction and gel electrophoresis were performed with primers designed to amplify 490 bp that included the plasmid's ligation site between the maize ubiquitin and the gdhA genes. The gdhA corn-derived DNA and diet served as positive assay controls, and conventional corn DNA and distilled water acted as negative assay controls. Detection limits were 0.99 fg of target DNA confounded with 500 ng of conventional corn DNA per each 20 &L reaction. Transgenic DNA was detected in 71.43% of the stomach and 1.79% of the ileal ingesta samples from treatment animals but was not detected in the large intestine, white blood cells, plasma, liver, or muscle samples. Transgenic DNA was not detected in any sample from 0-h control animals. Stomach and ileal ingesta samples were further analyzed using real-time PCR. With an estimated limit of detection of 1.049 ag/microL, 89.29% of the stomach ingesta samples were positive (average 1.56 fg target DNA). The proportion of transgenic DNA to total DNA differed between diet and stomach ingesta samples (P < 0.001). Despite the greater sensitivity of real-time PCR, target DNA was detected in only 1.79% of ileal ingesta. These data suggest that the gdhA transgene began degradation in the stomach and was nondetectable in the large intestine.  相似文献   
94.
The mechanism of inhibition of alpha-chymotrypsin by benzoylsalireposide (1), a phenolic glycoside isolated from Symplocos racemosa, was investigated. Lineweaver-Burk and Dixon plots and their secondary replots showed that 1 was a non-competitive inhibitor of this enzyme with the Ki value of 29.60 microM.  相似文献   
95.
This review article is based on different aspects of wheat breeding for drought tolerance. Drought is regarded as one of the most serious threats to agriculture in Pakistan. Therefore, breeding for drought tolerance must be given top priority. Here, we try to study various options available to wheat breeders exploring the underlying mechanisms of drought tolerance. The progress made in conventional and non-conventional (molecular) based approaches with potential findings and constraints are reviewed in this article. Equipped with such information, it will be possible for breeders to further explore the mysteries of drought tolerance and to select genotypes with an improved yield under water-deficit conditions.  相似文献   
96.
The availability of a genetically diverse gene pool is vitally important in varietal development. Molecular markers are being extensively utilized to explore the genetic diversity among native and exotic germplasm. This study was designed to reveal the genetic diversity and patterns of relationships among the 20 accessions/genotypes representative of basmati and non-basmati rice from the existing rice gene pool using RAPD markers. Employing RAPD, 17 decamer oligonucleotide primers directed the amplification of 116 fragments, out of which 101 were polymorphic (87.06%) while 15 fragments were monomorphic (12.93%). Similarity coefficients had ranged from 0.47 to 0.90. The average genetic similarity was calculated 0.68 (68%). In this study, the coarse rice genotypes showed more polymorphism (85.84%) than the fine rice genotypes (61.76%). Genotypes were clustered into 8 distinct groups: A, B, C, D, E, F, G, and H but two genotypes, i.e., Shadab and Kangni-27 showed divergence from all the genotypes of the groups. Therefore, these diverse genotypes may be included in future breeding programmes.  相似文献   
97.
Potential of seed priming treatments in improving the performance of early planted maize was evaluated against timely planting. Seeds of maize hybrid FH-810 were soaked in water(hydropriming), Ca Cl2(2.2%, osmopriming), moringa leaf extracts(MLE 3.3%, osmopriming) and salicylic acid(SA, 50 mg L–1, hormonal priming) each for 18 h. Untreated and hydroprimed seeds were taken as control. Seeds primed with SA took less time in emergence and had high vigor in early planted maize. Amongst treatments, hormonal priming, reduced the electrical conductivity, increased the leaf relative and chlorophyll contents followed by osmopriming with Ca Cl2 at seedling stage. Likewise, plant height, grain rows and 1 000-grain weight, grain and biological yield and harvest index were also improved by seed priming; however hormonal priming and osmopriming with MLE were more effective in this regard. Improved yield performance by hormonal priming or osmopriming with MLE in early planting primarily owed to increased leaf area index, crop growth and net assimilation rates, and maintenance of green leaf area at maturity. In conclusion, osmopriming with MLE and hormonal priming with SA were the most economical treatments in improving productivity of early planted spring maize through stimulation of early seedling growth at low temperature.  相似文献   
98.
The aim of this study was to reduce the breakdown of hybrid vigour by crossing maize × teosinte subspecies through induced tetraploidy and to improve the biomass and reproductive fertility of the induced tetraploids. To achieve this, seeds of maize breeding lines selected from an open‐pollinated population ‘Sargodha‐2002’ and a maize × teosinte cross were germinated in colchicine solution (0·25, 0·5 or 1·0%) until they had a thick radical and protruded plumule. Colchicine at 0·5% induced the highest number of tetraploids with the lowest number of chimeric plants. The induced tetraploids of maize and maize × teosinte crosses showed a significant ( 0·05) increase in leaf area (5 and 14%), total soluble solids (20 and 18%), leaf oil percentage (42 and 12%) and leaf crude protein contents (10 and 14%) in leaves relative to the diploid subspecies. Moreover, induced tetraploidy also arrested hybrid vigour by slowing down the decay of heterosis in progenies (4x) for plant height, leaf biomass and leaf oil percentage. Induced maize × teosinte hybrid tetraploids selected for frequent bivalent chromosome pairing resulted in higher seed setting cob?1 (increased 58%), pollen fertility (increased 59%) and seed setting percentage (increased 100%) than the quadrivalent variant.  相似文献   
99.
H. Ali    T. M. Shah    N. Iqbal    B. M. Atta    M. A. Haq 《Plant Breeding》2010,129(1):116-119
A gene that confers double-podding in chickpea is considered to be important for breeding higher yielding cultivars. Double-podded mutants were produced from five desi- and four kabuli-type chickpea genotypes through induced mutations and stabilty was checked up to M13 generation. Desi-type produced higher number of mutants as compared with kabuli-type. The inheritance studies in induced mutants of six genotypes showed that the double-podded trait was governed by single recessive gene. Different genotypes and their double-podded mutants were also characterized through sequence-tagged microsatellite site marker, TA-80. Allelic variations were found in single-podded genotypes and eight different alleles were identified, while for double-poddedness no allelic variants were found in all the analysed mutants. Addition of bases in the double-podded mutants showed that there might be involvement of transposable elements in the production of double-podded mutants through mutagens.  相似文献   
100.
Raising yield and fiber quality of cotton through heterosis (hybrid vigor) has been an objective of plant breeders and scientists. Heterosis over mid parent for fiber-related traits was calculated in three crosses of cotton (Gossypium hirsutum L.) involving five cotton varieties, viz., CIM 506, CIM 702, CIM 443, FH 1000 and CIM 1100 being commercially grown in Pakistan. Heterosis was observed for all four characters. The cross CIM 443 × CIM 1100 showed maximum positive heterosis (8.57%) for ginning outturn (GOT) (%) followed by fineness (7.81%) and staple length (1.01%). Therefore, the cross CIM 506 × CIM 1100 appeared to be promising for providing potential breeding materials for further commercial exploitation of heterosis in Pakistan, and heterosis breeding has a great potential for increasing stagnant cotton yields around the world.  相似文献   
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