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41.
Mechanocomputational techniques in conjunction with artificial intelligence (AI) are revolutionizing the interpretations of the crucial information from the medical data and converting it into optimized and organized information for diagnostics. It is possible due to valuable perfection in artificial intelligence, computer aided diagnostics, virtual assistant, robotic surgery, augmented reality and genome editing (based on AI) technologies. Such techniques are serving as the products for diagnosing emerging microbial or non microbial diseases. This article represents a combinatory approach of using such approaches and providing therapeutic solutions towards utilizing these techniques in disease diagnostics. 相似文献
42.
Alcántara-Sánchez F Reynaga-Peña CG Salcedo-Hernández R Ruiz-Herrera J 《Antonie van Leeuwenhoek》2004,86(4):301-311
The effects of the Ca2+/H+ exchanger A23187 and the K+/H+ exchanger nigericin on the growth of Neurospora crassa were analyzed. Both ionophores had the same effects on the fungus. They both inhibited growth in liquid media, apical extension
being more affected than protein synthesis. A sudden challenge to either ionophore on solid media rapidly stopped hyphal extension.
Additionally, both ionophores induced profuse mycelium branching and upward hyphal growth. Hyphae growing on nigericin-containing
media also burst at the apex. Both ionophores caused a rapid inhibition in the apically-occurring synthesis of structural
wall polysaccharides, but they did not affect mitochondrial energy conservation. With the use of DiBAC, a membrane-potential
sensitive fluorophore, it was excluded that their effects were due to depletion of the plasma membrane potential. Considering
that both ionophores exchange H+ for different metallic ions, we concluded that their effect was due to dissipation of a proton gradient, which is directly
or indirectly involved in the apical growth of the fungus.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
43.
Rhamnolipids, produced by Pseudomonas aeruginosa, represent an important group of biosurfactants having various industrial, environmental, and medical applications. Current
methods for rhamnolipid quantification involve the use of strong hazardous acids/chemicals, indirect measurement of the concentration
of sugar moiety, or require the availability of expensive equipment (HPLC-MS). A safer, easier method that measures the whole
rhamnolipid molecules would significantly enhance strain selection, metabolic engineering, and process development for economical
rhamnolipid production. A semi-quantitative method was reported earlier to differentiate between the rhamnolipid-producing
and non-producing strains using agar plates containing methylene blue and cetyl trimethylammonium bromide (CTAB). In this
study, a rapid and simple method for rhamnolipid analysis was developed by systematically investigating the complexation of
rhamnolipids and methylene blue, with and without the presence of CTAB. The method relies on measuring the absorbance (at
638 nm) of the rhamnolipid−methylene blue complex that partitions into the chloroform phase. With P. aeruginosa fermentation samples, the applicability of this method was verified by comparison of the analysis results with those obtained
from the commonly used anthrone reaction technique. 相似文献
44.
Corti A 《Cellular and molecular neurobiology》2010,30(8):1163-1170
Chromogranin A (CgA) is an acidic glycoprotein belonging to a family of regulated secretory proteins stored in the dense core
granules of the adrenal medulla and of many other neuroendocrine cells and neurons. This protein is frequently used as a diagnostic
and prognostic serum marker for a range of neuroendocrine tumors. Circulating CgA is also increased in patients with other
diseases, including subpopulations of patients with non-neuroendocrine tumors, with important prognostic implications. A growing
body of evidence suggests that CgA is more than a diagnostic/prognostic marker for cancer patients. Indeed, results of in
vitro experiments and in vivo studies in animal models suggest that this protein and its fragments can affect several elements
of the tumor microenvironment, including fibroblasts and endothelial cells. In this article, recent findings implicating CgA
as a modulator of the tumor microenvironment and suggesting that abnormal secretion of CgA could play important roles in tumor
progression and response to therapy in cancer patients are reviewed and discussed. 相似文献
45.
Differential expression analysis for sequence count data 总被引:22,自引:0,他引:22
High-throughput sequencing assays such as RNA-Seq, ChIP-Seq or barcode counting provide quantitative readouts in the form
of count data. To infer differential signal in such data correctly and with good statistical power, estimation of data variability
throughout the dynamic range and a suitable error model are required. We propose a method based on the negative binomial distribution,
with variance and mean linked by local regression and present an implementation, DESeq, as an R/Bioconductor package. 相似文献
46.
Brüser T 《Applied microbiology and biotechnology》2007,76(1):35-45
The biotechnological production of recombinant proteins is challenged by processes that decrease the yield, such as protease
action, aggregation, or misfolding. Today, the variation of strains and vector systems or the modulation of inducible promoter
activities is commonly used to optimize expression systems. Alternatively, aggregation to inclusion bodies may be a desired
starting point for protein isolation and refolding. The discovery of the twin-arginine translocation (Tat) system for folded
proteins now opens new perspectives because in most cases, the Tat machinery does not allow the passage of unfolded proteins.
This feature of the Tat system can be exploited for biotechnological purposes, as expression systems may be developed that
ensure a virtually complete folding of a recombinant protein before purification. This review focuses on the characteristics
that make recombinant Tat systems attractive for biotechnology and discusses problems and possible solutions for an efficient
translocation of folded proteins. 相似文献
47.
A cytoplasmic NADH oxidase (NOX) was purified from a soil bacteria, Brevibacterium sp. KU1309, which is able to grow in the medium containing 2-phenylethanol as the sole source of carbon under an aerobic condition. The enzyme catalyzed the oxidation of NADH to NAD+ involving two-electron reduction of O2 to H2O2. The molecular weight of the enzyme was estimated to be 102 kDa by gel filtration and 57 kDa by SDS-PAGE, which indicates that the NOX was a homodimer consisting of a single subunit. The enzyme was stable up to 70 degrees C at a broad range of pH from 7 to 11. The enzyme activity increased about ten-fold with the addition of ammonium salt, while it was inhibited by Zn2+ (39%), Cu2+ (41%), Hg2+ (72%) and Ag+ (37%). The enzyme acts on NADH, but not on NADPH. The regeneration of NAD+ utilizing this enzyme made selective oxidation of mandelic acid or L: -phenylalanine possible. This thermostable enzyme is expected to be applicable as a useful biocatalyst for NAD+ recycling. 相似文献
48.
Syeda Mehpara Farhat Aamra Mahboob Ghazala Iqbal Touqeer Ahmed 《Biological trace element research》2017,177(1):115-121
Aluminum is associated with etiology of many neurodegenerative diseases specially Alzheimer’s disease. Chronic exposure to aluminum via drinking water results in aluminum deposition in the brain that leads to cognitive deficits. The study aimed to determine the effects of aluminum on cholinergic biomarkers, i.e., acetylcholine level, free choline level, and choline acetyltransferase gene expression, and how cholinergic deficit affects novel object recognition and sociability in mice. Mice were treated with AlCl3 (250 mg/kg). Acetylcholine level, free choline level, and choline acetyltransferase gene expression were determined in cortex, hippocampus, and amygdala. The mice were subjected to behavior tests (novel object recognition and social novelty preference) to assess memory deficits. The acetylcholine level in cortex and hippocampus was significantly reduced in aluminum-treated animals, as compared to cortex and hippocampus of control animals. Acetylcholine level in amygdala of aluminum-treated animals remained unchanged. Free choline level in all the three brain parts was found unaltered in aluminum-treated mice. The novel object recognition memory was severely impaired in aluminum-treated mice, as compared to the control group. Similarly, animals treated with aluminum showed reduced sociability compared to the control mice group. Our study demonstrates that aluminum exposure via drinking water causes reduced acetylcholine synthesis in spite of normal free choline availability. This deficit is caused by reduced recycling of acetylcholine due to lower choline acetyltransferase level. This cholinergic hypofunction leads to cognitive and memory deficits. Moreover, hippocampus is the most affected brain part after aluminum intoxication. 相似文献
49.
Seedlings of two barley genotypes (‘Maresi’ and wild form of Hordeum spontaneum) were treated with jasmonic acid (JA 5 μM and 15 μM) for 24 h, and then subjected to water stress (PEG 6000 solution of −
1.5 MPa). JA caused an increase in the content of ABA but not in that of proline and spermidine in the two studied genotypes.
The effect of the treatment did not depend on the applied JA concentration. The pre-stress treatment with JA changed plant
response to water deficit with regard to membrane injury. Treatment with a lower JA concentration (5 μM) caused a substantial
reduction of the stress-induced membrane damage in the both genotypes. A higher JA concentration (15 μM) caused the reduction
of membrane injury only in H. spontaneum and was ineffective in ‘Maresi’. JA had no influence on the leaf water status in water-stressed plants. A possible role of
JA in leaf ABA accumulation and alleviation of cell membrane injury under water deficit is discussed.
The work was partly supported by the Polish Committee For Scientific Research, grant No 5 PO6A 036 18 相似文献
50.
A significant macrophage and T-cell infiltrate commonly occurs in inflammatory joint conditions such as rheumatoid arthritis
that have significant bone destruction. Cytokines produced by activated macrophages and T cells are implicated in arthritis
pathogenesis and are involved in osteoclast-mediated bone resorption. The scope of the present review is to analyze current
knowledge and to provide a better understanding of how macrophage-derived factors promote the differentiation of a novel T-helper
subset (Th17) that promotes osteoclast formation and activation. 相似文献