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71.
72.
An attempt was made to induce estrus and ovulation in eight anestrus yaks by use of the Ovsynch protocol. Six out of eight yaks were successfully induced into estrus, and ovulation occurred in all the responding yaks 1-2 days after the second GnRH administration. Out of the six animals that responded to the treatment, two mated naturally with yak bulls, and calves were obtained from them. The other four animals were further administered a superovulatory regimen of Folltropin (FSH-P). Following Folltropin and Ilerin (a PGF(2alpha) analog) treatment, the animals were subjected to natural insemination. Only one animal in which natural mating occurred was flushed non-surgically for embryo recovery 7 days post-insemination. Thereafter, all the donor animals were administered with Ilerin. After 48-72 h, they came into heat and mated naturally with yak bulls, and calves were obtained from them after expiration of the normal gestation period. Following superovulation, the average numbers of palpable corpora lutea in the right and left ovaries were 2.25+/-0.6 and 1.75 +/-0.3, respectively. Three embryos were recovered by non-surgical flushing from a single animal. One embryo was transferred to a recipient yak, who produced one female calf after 258 days. This is the first report of production of a yak calf through embryo transfer-technology.  相似文献   
73.

Background

Midlife body weight status has been found to affect late life dementia outcomes. A cohort projections model was developed to assess the impact of midlife body mass index (BMI) profile on dementia in older Australians.

Methods

A baseline projection using age-sex specific dementia prevalence rates was constructed and the results of scenarios that took account of midlife BMI were compared with those from population ageing only.

Results

This modelling predicts that if the rising trend in midlife obesity and declining trend in midlife normal weight in Australia are to be taken into account in projecting future numbers of Australians with dementia then the number of people aged 65 or more years with dementia, by 2050, would be 14% higher than that expected from demographic ageing only. If midlife obesity prevalence was decreased to 20% and normal weight increased to 40% over the period of 2015–2025, then dementia cases among persons aged 65–69 years would be lower by about 10% in 2050 compared with the “doing nothing to stop current trends in obesity” projection.

Conclusion

The rising tide of obesity in Australian adults will increase the dementia epidemic expected in future years.  相似文献   
74.
Potent antimalarial compound artemisinin, 1 was bio-transformed to C-9 acetoxy artemisinin, 2 using soil microbe Penicillium simplissimum along with C-9 hydroxy derivative 3. The products were characterized using high field NMR and MS–MS data. The absolute stereochemistry of the newly generated chiral centers has been ascertained by COSY and 1D NOESY experiments. This is the first Letter of direct C-acetoxylation of artemisinin using microbial strains.  相似文献   
75.
The influenza A virus (IAV) has eight segmented single-stranded RNA genome containing a common and evolutionarily conserved non-coding region (NCRs) at 5′ and 3′ ends that are important for the virus replication. In this study, we designed an antisense oligonucleotide against the 3′ NCR of vital segments of the IAV genome to inhibit its replication. The results demonstrated that the co-transfection of Madine Darby Canine Kidney (MDCK) cells with the antisense oligonucleotide and the plasmids encoding the viral genes led to the down-regulation of the viral gene expression. The designed antisense molecules reduced the cytopathic effect caused by A/PR/8/34 (H1N1), A/Udorn/307/72 (H3N2), and A/New Caledonia/20/99 (H1N1) strains of IAV for almost 48 h. Furthermore, the intra-venous delivery of this oligonucleotide significantly reduced the viral titers in the lungs of infected mice and protected the mice from lethal effects of all the strains of influenza virus. The study demonstrated that the antisense oligonucleotide designed against the NCR region inhibits the expression of the viral genome. The decrease of the cytopathic effect in the MDCK cells and increase in survival of mice confirmed the reduction of virus multiplication and pathogenesis in the presence of antisense oligonucleotide. Thus, we demonstrate that a single antisense oligonucleotide is capable of providing protection against more than one strains of the IAV.  相似文献   
76.
In Nepal, live donor organ transplantation is only 14 years old with the first successful kidney transplant made in 2008 and a successful liver and bone marrow transplant made in 2016. However, transplantation of cadaveric cornea dates back to 1998. There are still no cases of animal-to-human organ transplantation in Nepal. There are stringent laws to regulate human body organ transplantation in Nepal which are amended from time to time. However, there is a racket of human traffickers who lure rural people from this low-income country into the illegal organ trade. Furthermore, there is a substantial lack of awareness of organ donation among the general public. This article focuses on the stipulations of ethical, legal, and practical issues of obtaining organs procured from living and brain-dead donors that support the process of transplantation in Nepal. In addition, the article also explores the legal and practical issues of organ trafficking and organ donation awareness in Nepal on the basis of factual data and findings from other studies.  相似文献   
77.
Photosynthesis Research - A mutated phytoene desaturase (pds) gene, pds-L504R, conferring resistance to the herbicide norflurazon has been reported as a dominant selectable marker for the genetic...  相似文献   
78.
Using a new isolate of Pseudomonas aeruginosa, we obtained 7 g cell dry wt (CDW/l) using 5 % (w/v) glucose. Crude polyhydroxyalkanoates were obtained at 14.6 % of CDW. FTIR and NMR analysis confirmed that this was a new co-polymer: 3-hydroxyvalerate-co-5-hydroxydecenoate. Differential scanning calorimetry analysis showed two different melting temperatures of the copolymer and also indicated the glass transition temperature to be 4 °C. The polydispersity index of the polymer was 1.059.  相似文献   
79.
Bacteria co‐ordinate their social behaviour in a density‐dependent manner by production of diffusible signal molecules by a process known as quorum sensing (QS). It is generally assumed that in homogenous environments and at high cell density, QS synchronizes cells in the population to perform collective social tasks in unison which maximize the benefit at the inclusive fitness of individuals. However, evolutionary theory predicts that maintaining phenotypic heterogeneity in performing social tasks is advantageous as it can serve as a bet‐hedging survival strategy. Using Pseudomonas syringae and Xanthomonas campestris as model organisms, which use two diverse classes of QS signals, we show that two distinct subpopulations of QS‐responsive and non‐responsive cells exist in the QS‐activated population. Addition of excess exogenous QS signal does not significantly alter the distribution of QS‐responsive and non‐responsive cells in the population. We further show that progeny of cells derived from these subpopulations also exhibited heterogeneous distribution patterns similar to their respective parental strains. Overall, these results support the model that bacteria maintain QS‐responsive and non‐responsive subpopulations at high cell densities in a bet‐hedging strategy to simultaneously perform functions that are both positively and negatively regulated by QS to improve their fitness in fluctuating environments.  相似文献   
80.
Isochrysis galbana and Isochrysis sp. are economically important microalgae from the division of haptophytes. Here, we report Agrobacterium-mediated stable DNA transfer into their nuclear genomes. Initial studies were performed to standardize co-cultivation media and determine the sensitivity of the microalgae to selective agents. Up to 1 mg/ml of the antibiotic hygromycin did not inhibit growth, whereas both the haptophytes bleached in artificial seawater (ASW) medium containing micromolar concentrations of the herbicide norflurazon. Co-cultivation of Isochrysis sp. and I. galbana with Agrobacterium tumefaciens strain LBA 4404 harboring the binary vector pCAMBIA 1380-pds-L504R yielded norflurazon-resistant (NR) colonies visible on selective plates after 20–30 days. pCAMBIA 1380-pds-L540R was constructed by cloning a mutated genomic phytoene desaturase (pds) gene from Haematococcus pluvialis as a selectable marker gene into the binary vector system pCAMBIA 1380. Co-cultivation of Isochrysis sp. with A. tumefaciens in ASW medium containing 200 μM of acetosyringone for 72 h produced the highest number of NR cells. For I. galbana, 100 μM of acetosyringone, ASW medium, and 48 h co-cultivation period appeared to be optimum co-cultivation parameters. The NR colonies kept their resistance phenotype for at least 24 months, even in the absence of selective pressure. The transfer of the pds gene in NR cells was shown by PCR amplification of the T-DNA sequences from the genomic DNA of NR cells and Southern blot analysis using T-DNA sequences as probes. The genetic manipulation described here will allow metabolic engineering and a better understanding of several biochemical pathways in the future.  相似文献   
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