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751.
752.
Klebsiella pneumoniae U25 is a multidrug resistant strain isolated
from a tertiary care hospital in Chennai, India. Here, we report the complete
annotated genome sequence of strain U25 obtained using PacBio RSII. This is the first
report of the whole genome of K. pneumoniaespecies from Chennai. It
consists of a single circular chromosome of size 5,491,870-bp and two plasmids of
size 211,813 and 172,619-bp. The genes associated with multidrug resistance were
identified. The chromosome of U25 was found to have eight antibiotic resistant genes
[blaOXA-1,blaSHV-28,
aac(6’)1b-cr,catB3, oqxAB,
dfrA1]. The plasmid pMGRU25-001 was found to have only one
resistant gene (catA1) while plasmid pMGRU25-002 had 20 resistant
genes [strAB, aadA1,aac(6’)-Ib,
aac(3)-IId,sul1,2,
blaTEM-1A,1B,blaOXA-9,
blaCTX-M-15,blaSHV-11, cmlA1,
erm(B),mph(A)]. A mutation in the porin OmpK36
was identified which is likely to be associated with the intermediate resistance to
carbapenems in the absence of carbapenemase genes. U25 is one of the few K.
pneumoniaestrains to harbour clustered regularly interspaced short
palindromic repeats (CRISPR) systems. Two CRISPR arrays corresponding to Cas3 family
helicase were identified in the genome. When compared to K.
pneumoniaeNTUHK2044, a transposase gene InsH of IS5-13
was found inserted. 相似文献
753.
Qasim A. Rafiq Karen Coopman Alvin W. Nienow Prof. Christopher J. Hewitt 《Biotechnology journal》2013,8(4):459-471
Human mesenchymal stem cell (hMSC) therapies have the potential to revolutionise the healthcare industry and replicate the success of the therapeutic protein industry; however, for this to be achieved there is a need to apply key bioprocessing engineering principles and adopt a quantitative approach for large-scale reproducible hMSC bioprocess development. Here we provide a quantitative analysis of the changes in concentration of glucose, lactate and ammonium with time during hMSC monolayer culture over 4 passages, under 100% and 20% dissolved oxgen (dO2), where either a 100%, 50% or 0% growth medium exchange was performed after 72h in culture. Yield coefficients, specific growth rates (h-1) and doubling times (h) were calculated for all cases. The 100% dO2 flasks outperformed the 20% dO2 flasks with respect to cumulative cell number, with the latter consuming more glucose and producing more lactate and ammonium. Furthermore, the 100% and 50% medium exchange conditions resulted in similar cumulative cell numbers, whilst the 0% conditions were significantly lower. Cell immunophenotype and multipotency were not affected by the experimental culture conditions. This study demonstrates the importance of determining optimal culture conditions for hMSC expansion and highlights a potential cost savings from only making a 50% medium exchange, which may prove significant for large-scale bioprocessing. 相似文献
754.
M. Naeem M. Masroor A. Khan Moinuddin Mohd. Idrees Tariq Aftab 《Plant Growth Regulation》2011,65(1):195-206
Triacontanol (TRIA) has been realized as a potent plant growth promoting substance for a number of agricultural and horticultural
crops. Out of a large number of essential oil bearing plants, mint (Mentha arvensis L.) constitutes the most important source of therapeutic agents used in the alternative systems of medicine. The mint plant
has marvelous medicinal properties. In view of enhancing growth, yield and quality of this medicinally important plant, a
pot experiment was conducted according to simple randomized block design. The experiment was aimed at studying the effect
of four concentrations of TRIA (10−0, 10−7, 10−6 and 10−5 M) on the performance of mint with regard to growth and other physiological attributes, crop yield and quality attributes
and the yield and contents of active constituents of the plant. The growth and other physiological parameters as well as yield
and quality attributes were studied at 100 and 120 DAP. The foliar application of TRIA at 10−6 M concentration significantly enhanced most of the growth and other physiological attributes, crop herbage yield and the
yield and content of active constituents (menthol, l-methone, isomenthone and menthyl acetate) of mint at both the stages. However, the next higher concentration of TRIA (10−5 M) exhibited slightly negative effect and did not further increase the values of the attributes studied, but it proved significantly
better than the control. Application of TRIA significantly enhanced the yield and content of all the active constituents determined
by GLC technique. 相似文献
755.
Lyophilization is a key strategy in the stabilization of biological materials. Protection of the lyophilized material from an oxidizing atmosphere is essential if stability is to be maintained under long term storage. Vials of lyophilized albumin closed by two methods and ampoules of albumin have been examined for moisture and oxygen ingress after storage both under conditions of stress for two months and under thermally accelerated conditions for one year. The results show that the gas and moisture contents of ampoules do not detectably change even under conditions of stress, in contrast to vials for which this study shows clearly detectable moisture ingress and suggests some oxygen ingress. This is consistent with the results of other studies. Thus, although vials may be satisfactory under constrained conditions of temperature and storage for limited periods of time, and are presently used satisfactorily for some working standards, it would be prudent to continue to use ampoules for storage of international reference materials which are intended for indefinite storage and for which stability is an essential requirement. 相似文献
756.
Following the injury and disability of the dominant male, the home range of a group of rhesus in a rural habitat in Aligarh district was significantly reduced from 40 acres to less than 10 acres. Throughout this injury and prior to his death, the male maintained his dominance in reference to a peripheral male who frequently attempted to enter the group. Upon the death of the dominant male, group leadership and dominance was assumed by a young subdominant male within the group and the peripheral male still remained outside the group. These observations indicate a strong social tradition in the maintenance of dominance within this wild rhesus group, and they emphasize the role of the dominant male in maintaining home range.This work was begun under grants from the U.S. Educational Foundation in India, and the U.S. Public Health Service (RG 6262 and RG-6262 S1), and has been continued since 1961 under the auspices of the Johns Hopkins Center for Medical Research and Training supported by USPHS Grant GM 11326. We are indebted to Mr. Mirza A. Beg and Dr. M. Farooq Siddiqi for assistance with field observations, and to Dr. F. B. Bang for administrative support. 相似文献
757.
Shabhat Rasool Ishfaq Ahmed Rubiya Dar Sheikh Gazalla Ayub Sabia Rashid Tariq Jan Tahir Ahmed Niyaz A. Naikoo Khurshid I. Andrabi 《Biochemical genetics》2013,51(3-4):323-333
This study looks at novel variants of the TGFβ1 gene and their potential association with high myopia in an ethnic population from Kashmir, India. Allele frequencies of 247 Kashmiri subjects (from India) with high myopia and 176 ethnically matched healthy controls were tested for Hardy–Weinberg disequilibrium. The genotype and allele frequencies were evaluated using chi-square or Fisher’s exact tests. One of the three SNPs in codon 10 showed a significant difference between patients and control subjects (rs1982073: p genotype = 0.003, p allele = 0.001). There were no statistically significant differences between patients and control subjects for the other two SNPs, rs1800471 at codon 25 and a novel variant at codon 52. SNP rs1982073, substituting proline with leucine, appeared to be significantly associated with high myopia (p < 0.05). In silico predictions show that substitutions are likely to have an impact on the structure and functional properties of the protein, making it imperative to understand their functional consequences in relation to high myopia. 相似文献
758.
759.
Sheikh Taha Majid Mahmood Haider Muhammad Salman Hanif Alvina Ali Haider Khan Abdur Rashid Li Ping Zubair Muhammad Farzand Ayaz Tariq Leeza Ouyang Xue Dong Hansong Zhang Meixiang 《Plant Growth Regulation》2022,96(3):383-396
Plant Growth Regulation - Harpin proteins, produced by gram-negative bacteria, can enhance the plant growth. The growth enhancing potential of the harpins are beneficial and may be associated with... 相似文献
760.
Therapeutic bacteriophages are emerging as a potential alternative to antibiotics and synergistic treatment of antimicrobial-resistant infections. This is reflected by their use in an increasing number of recent clinical trials. Many more therapeutic bacteriophage is being investigated in preclinical research and due to the bespoke nature of these products with respect to their limited infection spectrum, translation to the clinic requires combined understanding of the biology underpinning the bioprocess and how this can be optimized and streamlined for efficient methods of scalable manufacture. Bacteriophage research is currently limited to laboratory scale studies ranging from 1–20 ml, emerging therapies include bacteriophage cocktails to increase the spectrum of infectivity and require multiple large-scale bioreactors (up to 50 L) containing different bacteriophage–bacterial host reactions. Scaling bioprocesses from the milliliter scale to multi-liter large-scale bioreactors is challenging in itself, but performing this for individual phage-host bioprocesses to facilitate reliable and robust manufacture of phage cocktails increases the complexity. This study used a full factorial design of experiments approach to explore key process input variables (temperature, time of infection, multiplicity of infection, agitation) for their influence on key process outputs (bacteriophage yield, infection kinetics) for two bacteriophage–bacterial host bioprocesses (T4 – Escherichia coli; Phage K – Staphylococcus aureus). The research aimed to determine common input variables that positively influence output yield and found that the temperature at the point of infection had the greatest influence on bacteriophage yield for both bioprocesses. The study also aimed to develop a scaled down shake-flask model to enable rapid optimization of bacteriophage batch bioprocessing and translate the bioprocess into a scale-up model with a 3 L working volume in stirred tank bioreactors. The optimization performed in the shake flask model achieved a 550-fold increase in bacteriophage yield and these improvements successfully translated to the large-scale cultures. 相似文献