An ultrasensitive colorimetric assay based on a multi-amplification strategy employing Pt/IrO2@SA@HRP nanoflowers for the detection of progesterone in saliva samples

2021 ◽  
Vol 13 (9) ◽  
pp. 1164-1171
Author(s):  
Minglei Lu ◽  
Qiyi He ◽  
Yingying Zhong ◽  
Junkang Pan ◽  
Zhiting Lao ◽  
...  

Progesterone (P4) belongs to a factor that affects stress response and is a potential carcinogen, and saliva levels are expected to be a standard measurement for clinical diagnosis.

2017 ◽  
Vol 53 (65) ◽  
pp. 9055-9058 ◽  
Author(s):  
Jiuxing Li ◽  
Zhuangqiang Gao ◽  
Haihang Ye ◽  
Shulin Wan ◽  
Meghan Pierce ◽  
...  

A non-enzyme cascade amplification strategy for colorimetric assay of disease biomarkers with substantially enhanced detection sensitivity has been developed.


The Analyst ◽  
2015 ◽  
Vol 140 (22) ◽  
pp. 7657-7662 ◽  
Author(s):  
Qing Wang ◽  
Xiaohan Yang ◽  
Xiaohai Yang ◽  
Kemin Wang ◽  
Hua Zhang ◽  
...  

A novel unmodified gold nanoparticle (AuNP)-based colorimetric assay was demonstrated based on split aptamers and the hybridization chain reaction (HCR) amplification strategy.


2020 ◽  
Vol 8 (12) ◽  
pp. 2003
Author(s):  
Nao Ikeyama ◽  
Moriya Ohkuma ◽  
Mitsuo Sakamoto

Bacterial stress responses are closely associated with the survival and colonization of anaerobes in the human gut. Mesosutterella multiformis JCM 32464T is a novel member of the family Sutterellaceae, an asaccharolytic bacterium. We previously demonstrated energy generation via heme biosynthesis, which is coupled with nitrate reductase. Here, physiological and morphological changes in M. multiformis induced by exposure to nitrate were investigated. The ability of M. multiformis to reduce nitrate was determined using a colorimetric assay. A unique morphology was observed during nitrate reduction under anaerobic conditions. The association between nitrate concentration and cell size or cellular fatty acid composition was evaluated. Nitrate-induced responses of M. multiformis were compared to those of related species. An increase in cellular filamentation and the ratio of saturated: unsaturated fatty acids was mediated specifically by nitrate. This indicates a decrease in cell fluidity and low leakage. Furthermore, a similar response was not observed in other related species cultured in the presence of nitrate. Hence, the nitrate-induced stress response in new anaerobes such as M. multiformis was demonstrated. The response could also be involved in the conservation of menaquinones and the maximization of nitrate reduction.


Author(s):  
Tong Wensheng ◽  
Lu Lianhuang ◽  
Zhang Zhijun

This is a combined study of two diffirent branches, photogrammetry and morphology of blood cells. The three dimensional quantitative analysis of erythrocytes using SEMP technique, electron computation technique and photogrammetry theory has made it possible to push the study of mophology of blood cells from LM, TEM, SEM to a higher stage, that of SEM P. A new path has been broken for deeply study of morphology of blood cells.In medical view, the abnormality of the quality and quantity of erythrocytes is one of the important changes of blood disease. It shows the abnormal blood—making function of the human body. Therefore, the study of the change of shape on erythrocytes is the indispensable and important basis of reference in the clinical diagnosis and research of blood disease.The erythrocytes of one normal person, three PNH Patients and one AA patient were used in this experiment. This research determines the following items: Height;Length of two axes (long and short), ratio; Crevice in depth and width of cell membrane; Circumference of erythrocytes; Isoline map of erythrocytes; Section map of erythrocytes.


2019 ◽  
Vol 476 (21) ◽  
pp. 3141-3159 ◽  
Author(s):  
Meiru Si ◽  
Can Chen ◽  
Zengfan Wei ◽  
Zhijin Gong ◽  
GuiZhi Li ◽  
...  

Abstract MarR (multiple antibiotic resistance regulator) proteins are a family of transcriptional regulators that is prevalent in Corynebacterium glutamicum. Understanding the physiological and biochemical function of MarR homologs in C. glutamicum has focused on cysteine oxidation-based redox-sensing and substrate metabolism-involving regulators. In this study, we characterized the stress-related ligand-binding functions of the C. glutamicum MarR-type regulator CarR (C. glutamicum antibiotic-responding regulator). We demonstrate that CarR negatively regulates the expression of the carR (ncgl2886)–uspA (ncgl2887) operon and the adjacent, oppositely oriented gene ncgl2885, encoding the hypothetical deacylase DecE. We also show that CarR directly activates transcription of the ncgl2882–ncgl2884 operon, encoding the peptidoglycan synthesis operon (PSO) located upstream of carR in the opposite orientation. The addition of stress-associated ligands such as penicillin and streptomycin induced carR, uspA, decE, and PSO expression in vivo, as well as attenuated binding of CarR to operator DNA in vitro. Importantly, stress response-induced up-regulation of carR, uspA, and PSO gene expression correlated with cell resistance to β-lactam antibiotics and aromatic compounds. Six highly conserved residues in CarR were found to strongly influence its ligand binding and transcriptional regulatory properties. Collectively, the results indicate that the ligand binding of CarR induces its dissociation from the carR–uspA promoter to derepress carR and uspA transcription. Ligand-free CarR also activates PSO expression, which in turn contributes to C. glutamicum stress resistance. The outcomes indicate that the stress response mechanism of CarR in C. glutamicum occurs via ligand-induced conformational changes to the protein, not via cysteine oxidation-based thiol modifications.


VASA ◽  
2004 ◽  
Vol 33 (4) ◽  
pp. 247-251 ◽  
Author(s):  
Zeller ◽  
Koch ◽  
Frank ◽  
Bürgelin ◽  
Schwarzwälder ◽  
...  

Diagnosis of non-specific aorto-arteritis (NSAA, Takaysu's arteritis) is typically based on clinical and investigational parameters. We report here about two patients with clinically suspected diagnosis of a Takayasu's arteritis already under anti-inflammatory therapy in whom percutaneous transluminal atherectomy of subclavian and axillary artery stenoses was performed to relief the patients from symptoms – intermittent dyspraxia of the arms – and to verify the clinical diagnosis by histology. In the first case aorto-arteritis could be histologically confirmed through the analysis of plaque material including media structures excised from the subclavian and axillary arteries using a new device for atherectomy. The biopsy showed diffuse inflammation and granulomatous lesions with giant cells typically for Takayasu's disease. In the second patient, biopsy showed no acute or chronic inflammatory signs but only atherosclerotic lesions. Percutaneous transluminal atherectomy is therefore not only an interventional but also a diagnostic tool and should be used in every case of interventional therapy of suspected aorto-arteritis to make the clinical diagnosis and as a major consequence the initiation of an aggressive anti-inflammatory medical therapy more reliable.


VASA ◽  
2015 ◽  
Vol 44 (2) ◽  
pp. 122-128 ◽  
Author(s):  
Mandy Becker ◽  
Tom Schilling ◽  
Olga von Beckerath ◽  
Knut Kröger

Background: To clarify the clinical use of sonography for differentiation of edema we tried to answer the question whether a group of doctors can differentiate lymphedema from cardiac, hepatic or venous edema just by analysing sonographic images of the edema. Patients and methods: 38 (70 ± 12 years, 22 (58 %) females) patients with lower limb edema were recruited according the clinical diagnosis: 10 (26 %) lymphedema, 16 (42 %) heart insufficiency, 6 (16 %) venous disorders, 6 (16 %) chronic hepatic disease. Edema was depicted sonographically at the most affected leg in a standardised way at distal and proximal calf. 38 sets of images were anonymised and send to 5 experienced doctors. They were asked whether they can see criteria for lymphedema: 1. anechoic gaps, 2. horizontal gaps and 3. echoic rims. Results: Accepting an edema as lymphedema if only one doctor sees at least one of the three criteria for lymphatic edema on each single image all edema would be classified as lymphatic. Accepting lymphedema only if all doctors see at least one of the three criteria on the distal image of the same patient 80 % of the patients supposed to have lymphedema are classified as such, but also the majority of cardiac, venous and hepatic edema. Accepting lymphedema only if all doctors see all three criteria on the distal image of the same patients no edema would be classified as lymphatic. In addition we separated patients by Stemmers’ sign in those with positive and negative sign. The interpretation of the images was not different between both groups. Conclusions: Our analysis shows that it is not possible to differentiate lymphedema from other lower limb edema sonographically.


2019 ◽  
Vol 30 (3) ◽  
pp. 157-168
Author(s):  
Helmut Hildebrandt ◽  
Jana Schill ◽  
Jana Bördgen ◽  
Andreas Kastrup ◽  
Paul Eling

Abstract. This article explores the possibility of differentiating between patients suffering from Alzheimer’s disease (AD) and patients with other kinds of dementia by focusing on false alarms (FAs) on a picture recognition task (PRT). In Study 1, we compared AD and non-AD patients on the PRT and found that FAs discriminate well between these groups. Study 2 served to improve the discriminatory power of the FA score on the picture recognition task by adding associated pairs. Here, too, the FA score differentiated well between AD and non-AD patients, though the discriminatory power did not improve. The findings suggest that AD patients show a liberal response bias. Taken together, these studies suggest that FAs in picture recognition are of major importance for the clinical diagnosis of AD.


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