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101.
102.
Shelly Praveen V. Pawar Y. S. Ahlawat 《Journal of plant biochemistry and biotechnology.》2003,12(2):163-165
Somatic embryogenesis and plant regeneration from stem explants of kinnow mandarin, a hybrid of king and willow mandarins, are reported. It is an economically important cash crop of India with great deal of production and export. This is for the first time that callus induction and internodal regeneration has been successfully achieved in this citrus cultivar. Callus was induced from nodal segment (1-2 cm) of kinnow mandarin on Murashige and Skoog (MS) medium supplemented with α-naphthaleneacetic acid (NAA) and benzyl amino purine (BAP). Cotyledonary stage somatic embryos with regenerated shoots were induced on BAPenriched medium. Roots developed when regenerated shoots were excised and cultured on half strength MS medium supplemented with NAA only. 相似文献
103.
Shelly A. Pizarro Rachel Dinges Rachel Adams Ailen Sanchez Charles Winter 《Biotechnology and bioengineering》2009,104(2):340-351
Process analytical technology (PAT) is an initiative from the US FDA combining analytical and statistical tools to improve manufacturing operations and ensure regulatory compliance. This work describes the use of a continuous monitoring system for a protein refolding reaction to provide consistency in product quality and process performance across batches. A small‐scale bioreactor (3 L) is used to understand the impact of aeration for refolding recombinant human vascular endothelial growth factor (rhVEGF) in a reducing environment. A reverse‐phase HPLC assay is used to assess product quality. The goal in understanding the oxygen needs of the reaction and its impact to quality, is to make a product that is efficiently refolded to its native and active form with minimum oxidative degradation from batch to batch. Because this refolding process is heavily dependent on oxygen, the % dissolved oxygen (DO) profile is explored as a PAT tool to regulate process performance at commercial manufacturing scale. A dynamic gassing out approach using constant mass transfer (kLa) is used for scale‐up of the aeration parameters to manufacturing scale tanks (2,000 L, 15,000 L). The resulting DO profiles of the refolding reaction show similar trends across scales and these are analyzed using rpHPLC. The desired product quality attributes are then achieved through alternating air and nitrogen sparging triggered by changes in the monitored DO profile. This approach mitigates the impact of differences in equipment or feedstock components between runs, and is directly inline with the key goal of PAT to “actively manage process variability using a knowledge‐based approach.” Biotechnol. Bioeng. 2009; 104: 340–351 © 2009 Wiley Periodicals, Inc. 相似文献
104.
Arreguin S Nelson P Padway S Shirazi M Pierpont C 《Journal of inorganic biochemistry》2009,103(1):87-93
Parkinson’s disease (PD) is the second most common neurodegenerative disease after Alzheimers. The main pathological hallmark of Parkinson’s is the deterioration and death of neurons that produce the neurotransmitter dopamine. Much of the neuronal damage takes place in the substantia nigra, a small region of the midbrain that contains the cell bodies of neurons that produce dopamine. The deterioration and death of dopaminergic neurons are directly associated with misfolding and aggregation of proteins, principally α-synuclein, that are natively unfolded. Present also in the substantia nigra is an unusually high concentration of vestigial iron. Protein misfolding in non-genetic (sporadic) cases of PD has been associated with reactive oxygen species formed as products of O2 reduction by the combination of dopamine and iron. Combinations of Fe3+, dopamine hydrochloride (DAH+Cl), and various ancillary ligands have been studied as a function of pH in aqueous solution to determine the optimum pH for complex formation. With ancillary ligands (L4) derived from nitrilotriacetic acid and ethylenediamine diacetic acid spectral changes are consistent with the formation of L4Fe(DAH+) species that reach a maximum concentration at pH 7.2. With edta as the ancillary ligand, spectral features at pH 7 resemble those of Fe3+-catecholate complexes that contain catecholate ligands bonded through a single oxygen. This demonstrates the ability of the dopamine catechol functionality to penetrate the coordination sphere of even exceptionally stable iron chelates. 相似文献
105.
The sterile insect technique (SIT) is widely used to suppress or eradicate infestations of the Mediterranean fruit fly, Ceratitis capitata (Wied.), an insect whose broad polyphagy poses a serious threat to fruit and vegetable crops. The SIT involves the production, sterilization and release of sterile insects to obtain sterile male by wild female matings, thus yielding infertile eggs. Mass‐rearing over many generations is known to produce dramatic changes in the behaviour and life history of C. capitata. This study investigated the possibility that mass‐rearing also alters male response to trimedlure, a sex‐specific attractant widely used in detection and monitoring programmes. We compared captures of released males from a mass‐reared strain and a recently established colony of wild flies in trimedlure‐baited Jackson traps at three spatial scales – open field, large field enclosures (75 m2) and small field cages (7 m2) – in two separate years. In the first year, males were used independently of flight ability, while in the second year only males with demonstrated flight capability were used. Trap capture was scored 2 days after release for the open field and the large field enclosures but either 1 h or 1 day after release in the small field cages. The findings were consistent across these different experiments: wild‐like males were captured in significantly greater numbers than mass‐reared males in both years of study, except in the trials lasting 1 day in the small field cages where significantly more wild than mass‐reared males were captured in 1 year but not the other. These results are compared with other studies, and their implications for SIT are discussed. 相似文献
106.
Shelly L. Thomas Robert G. Wagner William A. Halteman 《Biodiversity and Conservation》2009,18(9):2405-2419
In order to maintain biodiversity in forests, it has been recommended that harvests be designed after patterns of natural
disturbance. Using a long-term study that includes harvest treatments designed to emulate tree-fall gap disturbances in Maine’s
Acadian forest, we examined how the species richness, abundance, diversity, and assemblage similarity of click beetles inhabiting
coarse woody material (CWM) were affected by gap harvesting and CWM characteristics (diameter, degree of decay, and type of
wood). There were few differences in beetle assemblages between 0.07 and 0.12 ha harvest gap treatments. Four of the most
common species had higher abundances under a closed forest canopy than within harvest gaps. Species richness and total abundance
were higher in CWM that had larger diameters and were more decayed. Species assemblages also differed with the degree of wood
decomposition. Diversity was higher in CWM from softwood trees than hardwood trees. Results from this study suggest that small
(<0.2 ha) harvest gaps with living trees retained throughout the gap can maintain click beetle assemblages similar to that
of an unharvested forest. Forest managers also need to address the temporal continuity of CWM, including different types of
wood (hardwood and softwood), a range of decay conditions, and a range of diameter classes, especially larger diameters (>35 cm). 相似文献
107.
Abinav K. Singh Shelly Praveen Bhanu P. Singh Anupam Varma Naveen Arora 《Transgenic research》2009,18(6):877-887
Genetic engineering of food crops has significantly influenced the agricultural productivity over the past two decades. It
has proved a valuable tool, offering crops with higher yields, improved nutritional quality, resistance against pesticides,
herbicides and tolerance against abiotic stresses. However, the safety assessment of genetically engineered (GE) crops is
prerequisite before introduction into human food chain. The present study was aimed to assess the toxicity and allergenicity
of leaf curl virus resistant GE tomato compared to its wild-type species. Balb/c mice fed with genetically engineered or wild-type
tomato did not show significant differences in growth, body weight (P > 0.05) and food consumption when compared with control mice. Values for serum glutamic oxaloacetic transaminase and serum
glutamic pyruvic transaminase, urea and cholesterol were comparable in GE and wild-type tomato fed mice. Mice immunized with
GE or wild-type tomato extract showed low IgE response. Lung histology of ovalbumin fed mice showed bronchoconstriction with
eosinophilic infiltration whereas GE or wild-type tomato showed no cellular infiltration with normal airways. Genetically
engineered and wild-type tomato sensitized mice demonstrated similar IL-4 release in splenic cell culture supernatant. GE
and wild tomato extract on ELISA showed comparable IgE binding (P > 0.05) with food allergic patients’ sera. In conclusion, genetically engineered tomato showed no toxicity in mice and allergenicity
is similar to the wild-type tomato. 相似文献
108.
Ranjeet R. Kumar Suneha Goswami Mohammad Shamim Kavita Dubey Khushboo Singh Shweta Singh Yugal K. Kala Ravi R.K. Niraj Akshay Sakhrey Gyanendra P. Singh Monendra Grover Bhupinder Singh Gyanendra K. Rai Anil K. Rai Viswanathan Chinnusamy Shelly Praveen 《Functional & integrative genomics》2017,17(6):621-640
109.
Identification of tissue‐specific transcriptional markers of caloric restriction in the mouse and their use to evaluate caloric restriction mimetics
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110.