scholarly journals Oral Artesunate Dose-Response Relationship in Acute Falciparum Malaria

2002 ◽  
Vol 46 (3) ◽  
pp. 778-782 ◽  
Author(s):  
Brian J. Angus ◽  
Itaporn Thaiaporn ◽  
Kenechanh Chanthapadith ◽  
Yupin Suputtamongkol ◽  
Nicholas J. White
Keyword(s):  
Falciparum Malaria ◽  
Dose Response ◽  
Parasite Clearance ◽  
Multidrug Resistant ◽  
Maximum Effect ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
To Receive ◽  
The Relationship

ABSTRACT The combination of an oral artemisinin derivative (usually artesunate) and mefloquine has become standard treatment for multidrug-resistant falciparum malaria in several parts of Southeast Asia. The doses of artesunate used in monotherapy and combination treatment have largely been derived empirically. In order to characterize the in vivo dose-response relationship for artesunate and thus rationalize dosing, 47 adult patients with acute uncomplicated falciparum malaria and parasitemia ≥1% were randomized to receive a single oral dose of artesunate varying between 0 and 250 mg together with a curative dose of oral mefloquine. Acceleration of parasite clearance was used as the pharmacodynamic variable. An inhibitory sigmoidal maximum effect (E max) pharmacodynamic model typical of a dose-response curve was fitted to the relationship between dose and shortening of parasite clearance time (PCT). The E max was estimated as 28.6 oral h, and the 50% effective concentration was 1.6 mg/kg of body weight. These results imply that there is no reduction in PCTs with the use of single doses of artesunate higher than 2 mg/kg, and this therefore reflects the average lower limit of the maximally effective dose.

Underestimation of Dose - Response Relationship with Particular Reference to the Relationship between the Dietary Intake of Mercury and its Concentration in Blood

1988 ◽  
Vol 7 (2) ◽  
pp. 129-132 ◽  
Author(s):  
J.C. Sherlock ◽  
M.J. Quinn
Keyword(s):  
Linear Regression ◽  
Dietary Intake ◽  
Dose Response ◽  
Mercury Concentration ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Blood Mercury ◽  
Relationship Of ◽  
The Relationship ◽  
Blood Mercury Concentration

Wide discrepancies have been observed between controlled and uncontrolled intake studies of the relationship of blood mercury concentration to intake of mercury. The probable reason for the apparent discrepancies is that the within-subject variation of mercury intake in the uncontrolled studies was almost certainly considerably larger than the within-subject variation in blood mercury concentration; in these circumstances, the apparent slope obtained from a linear regression of blood mercury on intake will invariably be much smaller than the true slope. Studies of the exposure or intake of any substance should therefore include a consideration of the likely within-subject variation in the exposure or intake relative to that in the effect.

scholarly journals Association of psychiatric comorbidities with the risk of transport accidents in ADHD and MPH

2021 ◽  
Vol 30 ◽  
Author(s):  
Yi-Chun Liu ◽  
Vincent Chin-Hung Chen ◽  
Yao-Hsu Yang ◽  
Yi-Lung Chen ◽  
Michael Gossop
Keyword(s):  
Dose Response ◽  
Case Series ◽  
Autism Spectrum ◽  
Research Database ◽  
Accident Risk ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Series Analysis ◽  
The Relationship ◽  
Transport Accidents

Abstract Aims Although the relationship between attention-deficit/hyperactivity disorder (ADHD) and transport accidents has been shown, there is limited information on the relationship between medication and dose–response effects and transport accident risk. This study aims to determine whether young people with ADHD, including adolescents, are more prone to transport accidents than those without, and the extent to which methylphenidate (MPH) prescription in these patients reduces the risk. Methods We identified 114 486 patients diagnosed with ADHD from Taiwan's National Health Insurance Research Database from 1997 to 2013. Using a Cox regression model, we compared the risk of transport accidents between ADHD and non-ADHD groups and estimated the effect of MPH on accidents. Furthermore, we applied a self-control case-series analysis to compare the risk of accidents during the medication periods with the same patients' non-medication periods. Results Male ADHD patients had a higher risk of transport accidents than non-ADHD individuals (adjusted hazard ratio [aHR] = 1.24, [95% confidence interval (CI) 1.10–1.39]), especially for those comorbid with epilepsy, oppositional defiant disorder/conduct disorder (ODD/CD), and intellectual disabilities (ID). Female ADHD patients showed no relationship, except for comorbid with autism spectrum disorder (ASD) or ID. We found a reduced risk of transport accidents in patients with ADHD with MPH medication than those without MPH, with a plausible dose–response relationship (aHR of 0.23 to 0.07). A similar pattern was found in self-controlled case-series analysis. Conclusions Male patients with ADHD, especially those comorbid with epilepsy, ODD/CD, or ID, were at high risk of transport accidents. Female patients, when comorbid with ASD or ID, also exhibited a higher risk of accidents. MPH treatment lowered the accident risk with a dose–response relationship.

scholarly journals Factors that Determine the in vivo Dose-Response Relationship for Stable Chromosome Aberrations in A-Bomb Survivors

1992 ◽  
Vol 33 (SUPPLEMENT) ◽  
pp. 206-214 ◽  
Author(s):  
AKIO A. AWA ◽  
MIMAKO NAKANO ◽  
KAZUO OHTAKI ◽  
YOSHIAKI KODAMA ◽  
JOE LUCAS ◽  
...  
Keyword(s):  
Dose Response ◽  
Chromosome Aberrations ◽  
Response Relationship ◽  
Dose Response Relationship

scholarly journals Critical Evaluation of Two Commercial Biocontrol Agents for Their Efficacy against B. cinerea under In Vitro and In Vivo Conditions in Relation to Different Abiotic Factors

Agronomy ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1868
Author(s):  
Gurkan Tut ◽  
Naresh Magan ◽  
Philp Brain ◽  
Xiangming Xu
Keyword(s):  
Dose Response ◽  
Abiotic Factors ◽  
Critical Evaluation ◽  
Leaf Disc ◽  
Biocontrol Agents ◽  
In Vivo Studies ◽  
Response Relationship ◽  
Dose Response Relationship

The study evaluated the dose–response relationship of two commercial microbial biocontrol agents, Bacillus subtilis and Gliocladium catenulatum, against Botrytis cinerea both in vitro and in vivo. Inoculum doses, formulation, temperature and foliar leaf part all affected the control achieved by the two BCAs. In vitro competition assays on modified PDA plates tested a range of BCA doses (log10 3–10 CFUs or spores/droplet) at 4, 10 and 20 °C on the development of B. cinerea colonies. The dose–response relationship was influenced by both the BCA formulation and temperature. In vivo studies on lettuce plants in semi-commercial greenhouses examined the BCA dose (log10 5–9 CFUs or spores/mL) for controlling B. cinerea with a high inoculum (log10 6 spores/mL). Leaf disc assays showed that the dose–response relationship was influenced by the leaf parts sampled. These results suggest that the dose–response relationship between a BCA and specific pathogen will be significantly influenced by environmental conditions, formulation and plant phyllosplane tissue.

scholarly journals The level of bilirubin and the risk of ischemic stroke: a systematic review and dose-response meta-analysis of real-world studies

2020 ◽  
Author(s):  
Xiao Wang ◽  
Yang Zhou ◽  
Xiaofei Ye ◽  
Fangchen Liu ◽  
Xi Zhu ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Dose Response ◽  
Meta Analysis ◽  
Epidemiological Studies ◽  
Secondary Outcome ◽  
Serum Total Bilirubin ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Meta Analyses ◽  
The Relationship

Abstract Background: Bilirubin, a marker of hepatic and hematological diseases in clinical practice, is not only a waste end-product but also an antioxidant that may protect against diseases associated with oxidative stress. Numerous epidemiological studies have shown an inverse relationship between the serum total bilirubin (TBIL) level and the risk of ischemic stroke (IS). However, markedly elevated TBIL levels may exert neurotoxic effects. Based on this, we conducted a dose-response meta-analysis to quantify the relationship between blood TBIL and IS as well as between TBIL and all types of stroke (AS) in the physiological range of bilirubin.Methods: PubMed, Embase, Web of Science, and Cochrane Central databases were searched up to March 2019. Additional studies were identified by reviewing references and contacting authors. Categorical and dose-response meta-analyses were performed to quantify the relationship between TBIL and IS. The primary outcome was ischemic stroke, and the secondary outcome was all types of stroke.Results: Nine observational studies (seven publications) involving 110,032 participants and 3710 stroke cases were included for analysis. The average OR of IS for every 1 µmol/L increment in TBIL level was 0.978 (95% CI: 0.957–0.999). The summary OR of AS for every 1 µmol/L increment in TBIL level was 0.974 (95% CI: 0.956–0.992). Subgroup analysis based on gender showed a negative dose-response relationship between the circulating TBIL level and IS or AS in males, but not in females.Conclusions: The present study found a negative dose-response relationship between the circulating TBIL level and the risk of IS or AS within physiologic range of serum TBIL in males. Moderately elevated blood TBIL levels might be associated with a diminished prevalence of IS. Every 1 µmol/L increment in serum TBIL level was associated with a 2.2% decrease in the risk of IS and a 2.6% decrease in the risk of AS. However, due to the limitations in the number of included studies and their quality, large-scaled prospective cohort studies are needed to confirm the conclusion of the current analysis.Trial registration: This study was registered at PROSPERO (https://www.crd. york.ac.uk/PROSPERO/[CRD42017075988]).

scholarly journals Aggressive incidents in psychiatric hospitals on heat days

BJPsych Open ◽  
2021 ◽  
Vol 7 (4) ◽  
Author(s):  
Frank Eisele ◽  
Erich Flammer ◽  
Tilman Steinert ◽  
Hans Knoblauch
Keyword(s):  
Global Warming ◽  
Dose Response ◽  
Aggressive Behaviour ◽  
Psychiatric Patients ◽  
Psychiatric Hospitals ◽  
Patient Treatment ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Increasing Temperature ◽  
The Relationship

This study explores the relationship between temperature and the number of aggressive incidents and coercive interventions in the years 2007–2019 in six psychiatric hospitals in the south of the Germany with a total of 1007 beds. The number of aggressive incidents among 164 435 admissions was significantly higher on ‘heat days’ (≥30°C). Furthermore, there was a dose–response relationship between the number of aggressive incidents and increasing temperature. In contrast, the number of coercive interventions was not related to temperature. Considering the background of global warming, rising temperature could result in more frequent aggressive behaviour during in-patient treatment of psychiatric patients.

scholarly journals 35 years after the Chernobyl NPP accident: methods of retrospective dosimetry in assessing of the consequences of large-scale uncontrolled radiation exposures, their subsequent development and application in oncoradiology (experience of A. Tsyb MRRC)

2021 ◽  
Vol 30 (2) ◽  
pp. 7-24
Author(s):  
V.F. Stepanenko ◽  
◽  
A.D. Kaprin ◽  
S.A. Ivanov ◽  
P.V. Shegay ◽  
...  
Keyword(s):  
Thyroid Cancer ◽  
Dose Response ◽  
Chernobyl Accident ◽  
Research Centre ◽  
Innovative Technology ◽  
Radiation Doses ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Retrospective Dosimetry

Individual retrospective dosimetry was developed at A. Tsyb Medical Radiological Research Centre (A. Tsyb MRRC) after the Chernobyl accident for assessment and analysis of radiation effects on people lived in radioactively contaminated settlements in the Kaluga and Bryansk regions. The method was also used in radiation epidemiology case-control studies within frames of international pilot projects. The ob-tained data demonstrated reliable dose-response relationship for thyroid cancer in patients with diag-nosed thyroid cancer, who were children and adolescents at the time of the accident and resided in radi-oactively contaminated areas in the Bryansk region. The dose-response relationship for diagnosed inva-sive breast cancer was found in women, resided in radioactively contaminated settlements since the acci-dent till the first diagnosis of cancer that was established within the period from October 2008 to February 2013. Their age at diagnosis was under 55 years. At the same time, no dose-response relationship for leu-kaemia was found in children under 5 years old at the time of the accident. The individual retrospective dosimetry method has been updated and used in pilot studies for verifying conservative estimates of radi-ation doses to the population exposed to radiation as a result of nuclear tests at the Semipalatinsk nuclear test site, as well as for verifying estimates of external radiation doses to people affected by the accident at the Fukushima Daiichi NPP. The method was also used for estimating individual doses from residual radi-oactivity for the survivors of the Hiroshima and Nagasaki atomic bombings. The long-term collaboration continues under bilateral International Collaboration Agreements between the National Medical Research Radiological Centre and leading research centres in the Republic of Kazakhstan and Japan. Since 2016 researchers and physicians of A. Tsyb MRRC have modi-fied method of stimulated luminescence of natural and synthetic materials and developed innovative technology in vivo dosimetry that has been put into clinical practice for estimating spatial radiation doses distribution in internal organs at risk during the brachytherapy of prostate cancer, gynecologic and recur-rent pelvic tumors, as well as for estimating local radiation dose to the skin of the breast gland with the tumor. The 35-year experience in the development and application of methods for individual retrospective dosimetry after the Chernobyl accident formed the basis for identifying future-pointing trends for the de-velopment of novel applications of stimulated luminescence techniques. Radiation-induced stimulated luminescence dosimetry can be applicable in uncontrolled radiation events; retrospective dosimetry method applicable for neutron beam radiation therapy is under development. The method of in vivo do-simetry is useful in radiation oncology. Now assembled thermoluminiscent micro-sized dosimeters are used for arterial radioembolization. At present, feasibility of using items of clothing and special inserts (buttons, fastenings, etc.), parts of wearable electronic devices as natural dosimeters, as well as the feasi-bility of using luminescent microdosimeters, made of different materials, after exposure to high LET radiation ranged from a fraction of mGy to the dose greater than 60 Gy have been examined. Development of flexible planar microdosimeter assemblies in order to obtain more detailed information about possible discrepancy in distribution of planned and actual radia-tion doses to patients during radiotherapy is considered.

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