JSFit: a method for the fitting and prediction of J- and S-shaped concentration–response curves

Wang, Zejun; Liu, Shu-Shen; Qu, Rui

doi:10.1039/c7ra13220d

Cited by 26 publications

(10 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…CRC, excluding polynomial regression and support vector regression [37], some nonmonotonic functions including three-parameter Brain and Cousens model [38,39], four-parameter Schabenberger model [40,41] and Brain and Cousens model [42], and five-parameter Beckon model [43] were generally required. The most effective and typical model for describing J-CRC was the fiveparameter functions, which were generally divided into two types including the addition form such as the Biphasic model [11] and Deng model [23] and multiplication form such as the Wang model [44,45] and Zhu model [46]. Biphasic model was good enough to describe J-CRC and just able to derive J-CRC left segment model (BPL) and J-CRC right segment model (BPR), so we used the biphasic function to fit the whole J-CRC.…”

Section: Component J-crc and Fittingmentioning

confidence: 99%

Novel Segmented Concentration Addition Method to Predict Mixture Hormesis of Chlortetracycline Hydrochloride and Oxytetracycline Hydrochloride to Aliivibrio fischeri

Zhou

et al. 2020

IJMS

View full text Add to dashboard Cite

Hormesis is a concentration-response phenomenon characterized by low-concentration stimulation and high-concentration inhibition, which typically has a nonmonotonic J-shaped concentration-response curve (J-CRC). The concentration addition (CA) model is the gold standard for studying mixture toxicity. However, the CA model had the predictive blind zone (PBZ) for mixture J-CRC. To solve the PBZ problem, we proposed a segmented concentration addition (SCA) method to predict mixture J-CRC, which was achieved through fitting the left and right segments of component J-CRC and performing CA prediction subsequently. We selected two model compounds including chlortetracycline hydrochloride (CTCC) and oxytetracycline hydrochloride (OTCC), both of which presented J-CRC to Aliivibrio fischeri (AVF). The seven binary mixtures (M1–M7) of CTCC and OTCC were designed according to their molar ratios of 12:1, 10:3, 8:5, 1:1, 5:8, 3:10, and 1:12 referring to the direct equipartition ray design. These seven mixtures all presented J-CRC to AVF. Based on the SCA method, we obtained mixture maximum stimulatory effect concentration (ECm) and maximum stimulatory effect (Em) predicted by SCA, both of which were not available for the CA model. The toxicity interactions of these mixtures were systematically evaluated by using a comprehensive approach, including the co-toxicity coefficient integrated with confidence interval method (CTCICI), CRC, and isobole analysis. The results showed that the interaction types were additive and antagonistic action, without synergistic action. In addition, we proposed the cross point (CP) hypothesis for toxic interactive mixtures presenting J-CRC, that there was generally a CP between mixture observed J-CRC and CA predicted J-CRC; the relative positions of observed and predicted CRCs on either side of the CP would exchange, but the toxic interaction type of mixtures remained unchanged. The CP hypothesis needs to be verified by more mixtures, especially those with synergism. In conclusion, the SCA method is expected to have important theoretical and practical significance for mixture hormesis.

show abstract

Section: Component J-crc and Fittingmentioning

confidence: 99%

Novel Segmented Concentration Addition Method to Predict Mixture Hormesis of Chlortetracycline Hydrochloride and Oxytetracycline Hydrochloride to Aliivibrio fischeri

Zhou

et al. 2020

IJMS

View full text Add to dashboard Cite

show abstract

“…fitting and prediction of J-and S-shaped concentrationresponse curves (JSFit) program [69]. The goodness of fit is expressed as the determination coefficient (R 2 ).…”

Section: Time-dependent Toxicity Testmentioning

confidence: 99%

The weak magnetic field (WMF) enhances the stimulation of polymyxin B sulfate (POL) on Vibrio qinghaiensis sp.-Q67

Wang

et al. 2020

Environ Sci Eur

Self Cite

View full text Add to dashboard Cite

Background: The weak magnetic field (WMF) can enhance the ability to remove target pollutants in wastewater, which drives us to consider whether WMF could give rise to the hormesis or not. In our previous study, it was found that polymyxin B sulfate (POL) can induce weak hormesis on Vibrio qinghaiensis sp.-Q67 (Q67). To this end, we set up four different WMF treatments during Q67 culture and POL exposure process, having no WMF in all cases (NW), adding WMF all the time (AW), exerting WMF only during the bacterial culture (BW), and exerting WMF only in POL exposure period (EW). Results: It was shown that the concentration-response curves (CRCs) of POL in four WMF treatments at the exposure times of 6, 9, and 12 h are non-monotonic hormetic curves where the maximum stimulative effects (E min) of POL in BW and EW are obviously larger than those in AW and NW. The maximum E min is 26.8% occurring in EW and 20.7% in BW at 6 h, while the max E min is 14.6% in NW at 9 h, it means that stimulations of POL in BW and EW are earlier and stronger than those in NW. These findings first indicated that WMF can enhance the hormesis of POL. Conclusions: This study showed that WMF as a key factor may influence the maximum stimulation effect of hormesis. The characteristic of biphasic (hormetic effect) challenges the traditional classical threshold model that is close to chemical risk assessment. But the mechanism of hormesis even now is inconclusive. WMF as a novelty and neglected factor has the potential to support the further development of hormesis mechanism.

show abstract

“…Inspired by the investigation showing that PPy not only could be used as the conducting polymer to enhance the electronic conductivity but also could be used as the active material to increase lithium storage, Fan et al. reported a polysulfur‐grafted poly(pyridinopyridine) (SPPY), which was obtained from the heat‐treated mixture of poly(acrylonitrile) (PAN) and sulfur at 350 °C (Scheme ) . The as‐prepared SPPY polymer can form a conjugated ladder backbone with grafted sulfur side chains.…”

Section: Nanostructured Conjugated Polymers For Rechargeable Lithiummentioning

confidence: 99%

Nanostructured Conjugated Polymers for Energy‐Related Applications beyond Solar Cells

Xie

Zhao

Lin

et al. 2016

Chemistry An Asian Journal

139

View full text Add to dashboard Cite

To meet the ever-increasing requirements for the next generation of sustainable and versatile energy-related devices, conjugated polymers, which have potential advantages over small molecules and inorganic materials, are among the most promising types of green candidates. The properties of conjugated polymers can be tuned through modification of the structure and incorporation of different functional moieties. In addition, superior performances can be achieved as a result of the advantages of nanostructures, such as their large surface areas and the shortened pathways for charge transfer. Therefore, nanostructured conjugated polymers with different properties can be obtained to be applied in different energy-related organic devices. This review focuses on the application and performance of the recently reported nanostructured conjugated polymers for high-performance devices, including rechargeable lithium batteries, microbial fuel cells (MFCs), thermoelectric generators, and photocatalytic systems. The design strategies, reaction mechanisms, advantages, and limitations of nanostructured conjugated polymers are further discussed in each section. Finally, possible routes to improve the performances of the current systems are also included in the conclusion.

show abstract

JSFit: a method for the fitting and prediction of J- and S-shaped concentration–response curves

Abstract: S- and J-shaped concentration–response curves (CRCs) can be satisfactorily described by one classical Hill equation and combines with two Hill equations respectively.

Cited by 26 publications

References 33 publications

Novel Segmented Concentration Addition Method to Predict Mixture Hormesis of Chlortetracycline Hydrochloride and Oxytetracycline Hydrochloride to Aliivibrio fischeri

Novel Segmented Concentration Addition Method to Predict Mixture Hormesis of Chlortetracycline Hydrochloride and Oxytetracycline Hydrochloride to Aliivibrio fischeri

The weak magnetic field (WMF) enhances the stimulation of polymyxin B sulfate (POL) on Vibrio qinghaiensis sp.-Q67

Nanostructured Conjugated Polymers for Energy‐Related Applications beyond Solar Cells

Contact Info

Product

Resources

About