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81.
Prion protein gene polymorphisms in four goat breeds of Pakistan 总被引:1,自引:0,他引:1
Four different goat breeds (Pak-Angora, Dera Din Panah, Naachi and Teddy) of Pakistan were selected to investigate polymorphism
in the prion protein gene (PrP gene) responsible for scrapie disease resistance in goats. Initially, genotyping of 187 animals
of these four breeds by restriction fragment length polymorphism (RFLP) was done to see the genotype for codon 136 and 154.
All the animals were monomorphic with a genotype of AARR except one animal of Teddy breed having the genotype of AARH. Sequencing
of PrP gene of twenty animals representing these four goat breeds revealed two genotypes PPSSSS and PPSSPS with haplotypes
PSS and PSP of PrP gene at the codon numbers 42, 138, and 240. All four breeds showed both wild type monomorphic sequence
and mutant polymorphic sequences of these codons. The mutants of 42 and 138 codons translate the same amino acids as with
the wild type sequences, while the mutant of codon 240 is responsible for a different amino acid translation i.e., serine
to proline. In short, this study provides preliminary information about alleles and genotypes of PrP gene in four goat breeds
of Pakistan. 相似文献
82.
Acarine regulators of water hyacinth in Kerala (India) 总被引:1,自引:0,他引:1
Screening of the mite fauna on water hyacinth, Eichhornia crassipes, at 25 localities throughout Kerala (India) yielded a list of 21 phytophagous species from nine families. Distribution of mites at these localities and type of injury produced suggested that Oligonychus biharensis and Orthogalumna terebrantis warrant further study. In an experimental set-up the injury caused by these mites was quantified. Infestation by Ol. biharensis lead to reduced photosynthesis by the host (significant loss in chlorophyll content). Injurious effects of Or. terebrantis involved leaf mining by the developing instars leading to wilting of the leaves resulting in reduced dry weight. The relative merits of the two species as potential control agents of water hyacinth are discussed. 相似文献
83.
Background
Xenobiotics are neurotoxins that dramatically alter the health of the child. In addition, an inefficient detoxification system leads to oxidative stress, gut dysbiosis, and immune dysfunction. The consensus among physicians who treat autism with a biomedical approach is that those on the spectrum are burdened with oxidative stress and immune problems. In a trial to understand the role of detoxification in the etiology of autism, selected parameters related to sulfur-dependent detoxification mechanisms in plasma of autistic children from Saudi Arabia will be investigated compared to control subjects. 相似文献84.
85.
P P Singh S Singh V C Dhawan W Haq K B Mathur G P Dutta R C Srimal B N Dhawan 《Journal of biological regulators and homeostatic agents》1991,5(4):142-146
Methionine-enkephalin (M-Enk) and its analogue compound 82/205 (10(-5) and 10(-6) M) inhibited elaboration of Plasmodium cynomolgi total antigens soluble in culture medium (P.c.SA)-induced colony-stimulating factors (CSFs) by monkey blood monocyte-derived macrophages, in vitro. Paradoxically, lower concentrations (10(-7)-10(-9) M) of both the peptides greatly augmented CSFs elaboration; 82/205 appeared to be nearly 2.3-fold more potent. Naloxone (10(-5) M) pretreatment of macrophages inhibited only the M-Enk- and 82/205-induced enhanced CSFs elaboration, suggesting an opiate receptors-mediated mechanism of action. None of the peptides or naloxone (10(-5)-10(-9) M) had any direct effect on the CSF elaboration by unstimulated macrophages. 相似文献
86.
Summary Data acquisition and computer control ofZymomonas mobilis fermentation for ethanol production has been studied. An HP 200 series microcomputer system was used in conjunction with an HP 3497A data acquisition unit. On-line ethanol, glucose and cell mass were measured for use as possible control variables. Dilution rate was used as the manipulative variable. A versatile, user-friendly data acquisition program was written to gather, control and analyze data from the continuous fermentation. The program allows user-given control and calibration algorithms so that sophisticated control policies, e.g., self-tuning regulator (STR) and instrumentation, can be implemented with relative ease. 相似文献
87.
Saba Haq Soumyadip Das Dong-Ho Kim Arun Pandian Chandrasekaran Seok-Ho Hong Kye-Seong Kim Suresh Ramakrishna 《生物化学与生物物理学报:疾病的分子基础》2019,1865(3):599-610
RNA-binding protein LIN28A is often highly expressed in human malignant tumors and is involved in tumor metastasis and poor prognosis. Knowledge about post-translational regulatory mechanisms governing LIN28A protein stability and function is scarce. Here, we investigated the role of ubiquitination and deubiquitination on LIN28A protein stability and report that LIN28A protein undergoes ubiquitination. Ubiquitin-specific protease 28 (USP28), a deubiquitinating enzyme, interacts with and stabilizes LIN28A protein to extend its half-life. USP28, through its deubiquitinating activity, antagonizes LIN28A protein turnover by reversing its proteasomal degradation. Our study describes the consequential impacts of USP28-mediated stabilization of LIN28A protein on enhancing cancer cell viability, migration and ultimately augmenting LIN28A-mediated tumor progression. Overall, our data suggest that a synergistic, combinatorial approach of targeting LIN28A with USP28 would contribute to effective cancer therapeutics. 相似文献
88.
We investigated the effect ofnanoscale topography on neurite development in pheochromocytoma (PC12 cells) by culturing the cells on substrates having nanoscale pillars and pores with sizes comparable with filipodia. We found that cells on nanopillars and nanopores developed fewer and shorter neurites than cells on smooth substrates, and that cells on nanopores developed more and longer neurites than cells on nanopillars. These results suggest that PC12 cells were spatially aware of the difference in the nanoscale structures of the underlying substrates and responded differently in their neurite extension. This finding points to the possibility of using nanoscale topographic features to control neurite development in neurons. 相似文献
89.
Hasan MA Mannan A Alam R Islam MT Amin MA Khan MS Islam MA Muzahid NH 《Bioinformation》2012,8(4):196-200
The issue of balanced nutrition is of great concern to human. Meat and fish are the best sources of protein. The affordability of these resources for people in developing countries is less. Thus, there is an increasing interest in pulses and its derivates as an alternative to fish and meat. Lectin and histone H1 are the most common proteins in various pulses and our interest is in identifying the dominant essential amino acids in them for use as supplements. However, actin and lectin are common among Oryza Sativa and cicer arietinum. We describe the amount of lectin and histone H1 in cicer arietinum, Lens culinaris and Pisum sativum in a comparative manner. cicer arietinum was found to contain more essential amino acids than Lens culinaris and Pisum sativum. The secondary structures of lectin and histone H1 protein were analyzed to gain functional inferences in these species. The comparative study shows the relatively poor presence of the amino acid methionine in most pulses. However, Oryza Sativa was found to contain sufficient methionine. The study shows that pulses (especially cicer arietinum) were a suitable alternative source to meat and fish for Lectin and Histone H1 balance. Hence, pulses could be suggested with rice for balanced protein diet. 相似文献
90.
Abraldes JG Iwakiri Y Loureiro-Silva M Haq O Sessa WC Groszmann RJ 《American journal of physiology. Gastrointestinal and liver physiology》2006,290(5):G980-G987
Increased nitric oxide (NO) is the main factor leading to the hyperdynamic circulation associated with advanced portal hypertension (PHT), but the initial mechanisms and the magnitude of increase in portal pressure required to trigger NO production are not known. We addressed these issues by studying systemic and splanchnic hemodynamics and endothelial NO synthase (eNOS) and VEGF expression in rats with different degrees of portal hypertension. Portal vein ligation (PVL) performed over needles of three different calibers (16-, 18-, and 20-gauge) yielded different degrees of PHT and portosystemic shunting. Compared with sham rats, all three groups of PVL rats exhibited features of hyperdynamic circulation. Rats with minimal portal hypertension (PVL with a 16-gauge needle) showed an early increase in VEGF and eNOS expression selectively at the jejunum. Immunofluorescence showed that VEGF expression was located in highly vascularized areas of the mucosa. Inhibition of VEGF signaling markedly attenuated the increase in eNOS expression. In conclusion, mild increases in portal pressure are enough to upregulate eNOS at the intestinal microcirculation, and this occurs, at least in part, through VEGF upregulation. 相似文献