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121.

Background

Biomarkers predicting tuberculosis treatment response and cure would facilitate drug development. This study investigated expression patterns of the co-stimulation molecule NKG2D in human tuberculosis and treatment to determine its potential usefulness as a host biomarker of tuberculosis drug efficacy.

Methods

Tuberculosis patients (n = 26) were recruited in Lahore, Pakistan, at diagnosis and followed up during treatment. Household contacts (n = 24) were also recruited. NKG2D expression was measured by qRT-PCR in RNA samples both ex vivo and following overnight mycobacterial stimulation in vitro. Protein expression of NKG2D and granzyme B was measured by flow cytometry.

Results

NKG2D expression in newly diagnosed tuberculosis patients was similar to household contacts in ex vivo RNA, but was higher following in vitro stimulation. The NKG2D expression was dramatically reduced by intensive phase chemotherapy, in both ex vivo blood RNA and CD8+ T cell protein expression, but then reverted to higher levels after the continuation phase in successfully treated patients.

Conclusion

The changes in NKG2D expression through successful treatment reflect modulation of the peripheral cytotoxic T cell response. This likely reflects firstly in vivo stimulation by live Mycobacterium tuberculosis, followed by the response to dead bacilli, antigen-release and finally immunopathology resolution. Such changes in host peripheral gene expression, alongside clinical and microbiological indices, could be developed into a biosignature of tuberculosis drug-induced cure to be used in future clinical trials.  相似文献   
122.
Biological Trace Element Research - Endoxylanase enzyme is used as poultry feed additive to degrade anti-nutritional factors like non-starch polysaccharides. Moreover, iron is one of the most...  相似文献   
123.
Biological Trace Element Research - The need for minerals during pregnancy in mammals increases by progress of gestation due to embryo development. Therefore, the supply of trace minerals for...  相似文献   
124.
Purpose

The main purpose of this study was to evaluate the use of an integrated life cycle assessment (LCA), artificial neural network, and metaheuristic optimization model to improve the sustainability of tomato-based cropping systems in Iran. The model outputs the combination of input usage in a tomato cropping system, which leads to the highest economic output and the least environmental impact.

Methods

The LCA inventory was created using data from 114 open-field tomato farms in the Alborz Province of Iran during one growing period in 2015. Among all management components, the main focus was on irrigation management systems. The optimization problem was designed by integrating three indicators: carbon footprint (CF), benefit-cost ratio (BCR), and energy use efficiency (EUE) as the objective of field tomato production. The functional unit was 1 kg of tomato aligned with the system boundary of the cradle to market life cycle. Three artificial neural networks (ANNs) were applied to model relationships between the inputs and three indices (CF, BCR, and EUE) as the objective functions. Multi-objective genetic algorithm (MOGA) and multi-objective particle swarm optimization (MOPSO) were used to minimize the CF and maximize the BCR and EUE indicators. The abovementioned aims have been pursued by developing codes in MATLAB software.

Results and discussion

CF, BCR, and EUE were calculated to be 0.26 kg CO2?eq (kg tomato)?1, 1.8, and 0.5, respectively. MOGA results envisage the possibility of an increase of 86% and 50% in the EUE and BCR and a 43% reduction in the CF of tomato production systems. Moreover, EUE and BCR increased by 83% and 49%, and CF was reduced by 39% from the optimum results obtained from the MOPSO algorithm. It was revealed that in order to optimize field tomato production with the target objectives of this study, a large additional use for irrigation pipes, plastic, and machinery in comparison to current situation is required, while a large reduction of biocide, chemical fertilizer, and electricity consumption is indispensable.

Conclusions

According to the results of our study, it was concluded that the optimal solutions require a modernization of irrigation systems and a decrease in the consumption of chemical fertilizers and pesticides. The implementation of management options for such solutions is discussed.

  相似文献   
125.
The present investigation on the iron (Fe) transfer from soil to plant and in turn to animal (cows), as a function of sampling periods was conducted at the Livestock Experimental Station Sargodha, Pakistan which falls under semi-arid conditions. Although the iron transfer from soil to forage increased consistently, the forage Fe content decreased progressively with increase in sampling period. Highest Fe transfer from forage to cow blood plasma was observed during October and lowest during January. The transfer of Fe from forage to animal milk was maximum during the months of October and January and minimum during December. The transfer of Fe to plasma and milk was found to be dependent variably on the growth stage of forage in this investigation. Based on the findings of the present study, it is evident that mineral supplementation with higher Fe availability is urgently warranted to the animals particularly during the months of December and January to enhance plasma Fe in the cows being reared at that livestock farm during the entire grazing period. Thus, obligatory supplementation of Fe to the ruminants is highly recommended. Since the processes involved in iron management system in humans, animals, and plants are basically similar, appropriate elemental management must be provided to the living organisms, otherwise deficient or excessive levels of iron may deteriorate the developing cells of the organisms.  相似文献   
126.
Intake of boron from food and drinking water may pose a risk to the public health above a certain concentration level. Therefore, knowledge of boron concentration in drinking water and food items is essential. In this context, samples of drinking water were collected from natural springs of the Neelum valley, Azad Kashmir, hit by devastating earthquake in 2005. In these samples, boron concentration was determined using neutron-induced radiography technique. To do so, unknown water samples, along with standard of known boron dried on CR-39 detectors, were irradiated with thermal neutrons. After exposure, CR-39 detectors were etched in 6 M NaOH at 70°C. The tracks produced due to the alpha particles and 7Li ions as a result of 10B(n,α)7Li reaction were counted under an optical microscope. The tracks produced in theses samples were then related to the boron contents. The measured boron concentration in water samples was found to vary from 0.105 ± 0.005 to 0.247 ± 0.013 mg/l with an average value of 0.17 ± 0.04 mg/l, which are within the acceptable limits.  相似文献   
127.
The space radiation environment consists of trapped particle radiation, solar particle radiation, and galactic cosmic radiation (GCR), in which protons are the most abundant particle type. During missions to the moon or to Mars, the constant exposure to GCR and occasional exposure to particles emitted from solar particle events (SPE) are major health concerns for astronauts. Therefore, in order to determine health risks during space missions, an understanding of cellular responses to proton exposure is of primary importance. The expression of DNA repair genes in response to ionizing radiation (X-rays and gamma rays) has been studied, but data on DNA repair in response to protons is lacking. Using qPCR analysis, we investigated changes in gene expression induced by positively charged particles (protons) in four categories (0, 0.1, 1.0, and 2.0 Gy) in nine different DNA repair genes isolated from the testes of irradiated mice. DNA repair genes were selected on the basis of their known functions. These genes include ERCC1 (5' incision subunit, DNA strand break repair), ERCC2/NER (opening DNA around the damage, Nucleotide Excision Repair), XRCC1 (5' incision subunit, DNA strand break repair), XRCC3 (DNA break and cross-link repair), XPA (binds damaged DNA in preincision complex), XPC (damage recognition), ATA or ATM (activates checkpoint signaling upon double strand breaks), MLH1 (post-replicative DNA mismatch repair), and PARP1 (base excision repair). Our results demonstrate that ERCC1, PARP1, and XPA genes showed no change at 0.1 Gy radiation, up-regulation at 1.0 Gy radiation (1.09 fold, 7.32 fold, 0.75 fold, respectively), and a remarkable increase in gene expression at 2.0 Gy radiation (4.83 fold, 57.58 fold and 87.58 fold, respectively). Expression of other genes, including ATM and XRCC3, was unchanged at 0.1 and 1.0 Gy radiation but showed up-regulation at 2.0 Gy radiation (2.64 fold and 2.86 fold, respectively). We were unable to detect gene expression for the remaining four genes (XPC, ERCC2, XRCC1, and MLH1) in either the experimental or control animals.  相似文献   
128.
The glycoprotein hormone receptor hinge region is the least conserved component and the most variable in size; the TSH receptor (TSHR) being the longest (152 amino acids; residues 261-412). The TSHR is also unique among the glycoprotein hormone receptor in undergoing in vivo intramolecular cleavage into disulfide-linked A- and B-subunits with removal of an intervening 'C-peptide' region. Experimentally, hinge region amino acids 317-366 (50 residues) can be deleted without alteration in receptor function. However, in vivo, more than 50 amino acids are deleted during TSHR intramolecular cleavage; furthermore, the boundaries of this deleted region are ragged and poorly defined. Studies to determine the extent to which hinge region deletions can be tolerated without affecting receptor function ('minimal hinge') are lacking. Using as a template the functionally normal TSHR with residues 317-366 deleted, progressive downstream extension of deletions revealed residue 371 to be the limit compatible with normal TSH binding and coupling with cAMP signal transduction. Based on the foregoing downstream limit, upstream deletion from residue 307 (307-371 deletion) was also tolerated without functional alteration, as was deletion of residues 303-366. Addressing a related issue regarding the functional role of the TSHR hinge region, we observed that downstream hinge residues 377-384 contribute to coupling ligand binding with cAMP signal transduction. In summary, we report the first evaluation of TSHR function in relation to proteolytic posttranslational hinge region modifications. Deletion of TSHR hinge amino acids 303-366 (64 residues) or 307-371 (65 residues) are the maximum hinge region deletions compatible with normal TSHR function.  相似文献   
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