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1.
Sharbati R. Singh Sunita Dalal Rohtas Singh A. K. Dhawan Rajwant K. Kalia 《Journal of plant biochemistry and biotechnology.》2012,21(2):220-228
Effect of season, media type, carbon source, growth regulators and transplanting media on micropropagation of Dendrocalamus asper, an important bamboo species, was examined. The season of explant collection played an important role in axillary bud sprouting and spring (February?CApril) was found to be the best period for explant collection. Among the different media MS was found to be the best for micropropagation. Maximum numbers (4.83/explant) of shoots were initiated in MS?+?15???M BAP. For shoot multiplication, MS medium supplemented with 10???M BAP and 75???M Adenine sulfate was used. BAP was superior to KIN for both explant establishment, as well as, shoot multiplication. Optimal rooting was achieved in shoots cultured on ? strength MS medium supplemented with 5???M each of IBA and NAA. Regenerated plantlets were acclimatized and hardened in green house using dune sand and vermi-compost (3:1) with 92.34% success and transferred to the field with 100% survival rate. In the field, plants supplied with FYM along with urea showed better growth and development. Macroproliferation, plant multiplication by separating the rooted tillers of well established in vitro raised plantlets after 5 to 6?months of growth in the green house could double the multiplication rate. More than 25000 in vitro raised plants were successfully transferred to the field and no morphological variations in growth were observed, thus proving the potential of tissue culture for raising large scale plantations of D. asper. 相似文献
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Ghan Shyam Lohiya Hubert Pirkle Hoan Nguyen Sunita Lohiya Tran Vuu 《The Western journal of medicine》1988,148(4):426-429
We reviewed records of all persons dying between 1979 and 1986 in eight California institutions for the mentally retarded. Autopsies had been done in 71% of the 1,181 deaths. Nine deaths were due to hepatocellular carcinoma, which invariably developed in carriers of hepatitis B surface antigen (HBsAg) and was fatal within four months of diagnosis. The mean age at death was 32.7 years. The incidence of hepatocellular carcinoma in HBsAg carriers was 140 times greater than in the US population. Persistent hepatitis B infection was probably etiologically related to hepatocellular carcinoma in this population, which is relatively free of exposure to other hepatocarcinogens. 相似文献
4.
S. K. Soni I. K. Sandhu K. S. Bath U. C. Banerjee P. R. Patnaik 《Folia microbiologica》1996,41(3):243-248
A strain of starch-assimilating yeast,Saccharomycopsis capsularis, isolated from Indian cereal-based fermented foods, produced significant levels of extracellular α-amylase and glucoamylase.
The enzymes reached their peak activities during the stationary phase at the end of the 5th and 4th day of cultivation, respectively.
The amylase yields were maximized by a proper choice of carbon and nitrogen sources, starting pH of the culture medium and
growth temperature. High activities of the enzymes were obtained through inexpensive agricultural commodities, such as wheat
bran and corn meal as carbon sources, and defatted soybean meal and peanut meal as nitrogen sources. A temperature of 28–32°C
and an initial pH of 4.5–5.0 were optimum. The crude amylase mixture could liquefy and saccharify a 1% starch solution completely
in 24 h at 50°C. 相似文献
5.
Optimization of biolistic method for transient gene expression and production of agronomically useful transgenic Basmati rice plants 总被引:4,自引:0,他引:4
We have developed a reproducible biolistic procedure for the efficient transformation of embryogenic suspension cells of an improved aromatic Indica rice variety, Pusa Basmati 1. The -glucuronidase gene was used to assay transient transformation; other plasmids carrying either a potato protease inhibitor 2 (Pin2) gene, or a late embryogenesis-abundant protein (LEA3) gene from barley, were used for the optimization of biolistic process and transgenic plant production. After optimization of the procedure, over 600 transient transformants and at least five fertile plants showing integrative transformation were obtained per bombarded filter. At least 30% of the plants were derived from independent transformation events. The new improved procedure involves the use of a reporter gene or other useful genes driven by the strong rice actin 1 gene (Act1) promoter, osmotic pre-conditioning of cells for 24 h on medium supplemented with 0.25 M mannitol prior to bombardment, use of gold particles for DNA delivery, and use of plant regeneration medium with high (1.0%) agarose concentration. 相似文献
6.
Ambikesh Soni Manohar Prasad Bhandari Gagan Kant Tripathi Priyavand Bundela Pradeep Kumar Khiriya Purnima Swarup Khare Manoj Kumar Kashyap Abhijit Dey Balachandar Vellingiri Suresh Sundaramurthy Arisutha Suresh José M. Pérez de la Lastra 《Journal of cellular and molecular medicine》2023,27(6):737-762
In recent years, drug manufacturers and researchers have begun to consider the nanobiotechnology approach to improve the drug delivery system for tumour and cancer diseases. In this article, we review current strategies to improve tumour and cancer drug delivery, which mainly focuses on sustaining biocompatibility, biodistribution, and active targeting. The conventional therapy using cornerstone drugs such as fludarabine, cisplatin etoposide, and paclitaxel has its own challenges especially not being able to discriminate between tumour versus normal cells which eventually led to toxicity and side effects in the patients. In contrast to the conventional approach, nanoparticle-based drug delivery provides target-specific delivery and controlled release of the drug, which provides a better therapeutic window for treatment options by focusing on the eradication of diseased cells via active targeting and sparing normal cells via passive targeting. Additionally, treatment of tumours associated with the brain is hampered by the impermeability of the blood–brain barriers to the drugs, which eventually led to poor survival in the patients. Nanoparticle-based therapy offers superior delivery of drugs to the target by breaching the blood–brain barriers. Herein, we provide an overview of the properties of nanoparticles that are crucial for nanotechnology applications. We address the potential future applications of nanobiotechnology targeting specific or desired areas. In particular, the use of nanomaterials, biostructures, and drug delivery methods for the targeted treatment of tumours and cancer are explored. 相似文献
7.
Germinating pigeonpea seeds were found to release factor(s), which dramatically altered the growth pattern of rice seedlings. This included an increased sensitivity of roots to gravity, an increase in seminal root length, and increased density of branch roots on the seminal root and suppression of root hair formation. Furthermore, the known characteristic responses of rice to ethylene (namely, coleoptile growth promotion and induction of senescence) were inhibited by the presence of these factor(s). This altered growth pattern of rice seedlings was similar to that brought about by the ethylene-antagonist, silver nitrate. Further, the change in growth pattern in rice was specifically reversed by ethrel. In addition, in wild-type Arabidopsis thaliana these factors suppressed formation of root hair, the development of which is known to be promoted by ethylene. In contrast, in a mutant A. thaliana which shows constitutive ethylene response ( ctr1-1 ), the factors failed to inhibit root hair formation. These observations indicated that germinating pigeonpea seeds secrete factor(s), which have antiethylene-like effects. 相似文献
8.
9.
DNA replication in eukaryotic cells is restricted to the S-phase of the cell cycle. In a cell-free replication model system, using SV40 origin-containing DNA, extracts from G1 cells are inefficient in supporting DNA replication. We have undertaken a detailed analysis of the subcellular localization of replication proteins and cell cycle regulators to determine when these proteins are present in the nucleus and therefore available for DNA replication. Cyclin A and cdk2 have been implicated in regulating DNA replication, and may be responsible for activating components of the DNA replication mitiation complex on entry into S-phase. G1 cell extracts used for in vitro replication contain the replication proteins RPA (the eukaryotic single-stranded DNA binding protein) and DNA polymerase as well as cdk2, but lack cyclin A. On localizing these components in G1 cells we find that both RPA and DNA polymerase are present as nuclear proteins, while cdk2 is primarily cytoplasmic and there is no detectable cyclin A. An apparent change in the distribution of these proteins occurs as the cell enters S-phase. Cyclin A becomes abundant and both cyclin A and cdk2 become localized to the nucleus in S-phase. In contrast, the RPA-34 and RPA-70 subunits of RPA, which are already nuclear, undergo a transition from the uniform nuclear distribution observed during G1, and now display a distinct punctate nuclear pattern. The initiation of DNA replication therefore most likely occurs by modification and activation of these replication initiation proteins rather than by their recruitment to the nuclear compartment. 相似文献
10.
Phage M-1 produced clear plaques with a halo in the lawn of Rhizobium japonicum D211. A one step growth curve of phage M-1 showed a latent period of 3 h, burst size of 55 and rise period of 2 h. The inactivation of phage M-1 was found to be dependent upon the concentraion of d-glucosomanine. The neutralization kinetics of phage M-1 by antiphage serum gave a K value (velocity constant) of 83.1 min–1. Transduction of str and kan was studied in the presence of antiphage serum and d-glucosamine. Cotransduction of different antibiotic resistance markers suggested that the system can be further explored for high resolution mapping in R. japonicum.Abbreviations YM
yeast mannitol medium
- PFU
plaque forming unit
-
moi
multiplicity of infection
- EOP
efficiency of plating 相似文献