scholarly journals Optimized Weighted Nearest Neighbours Matching Algorithm for Control Group Selection

Algorithms ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 356
Author(s):  
Szabolcs Szekér ◽  
Ágnes Vathy-Fogarassy
Keyword(s):  
Simulated Annealing ◽  
Group Selection ◽  
Feature Space ◽  
Treated Group ◽  
Control Group ◽  
Case Control Studies ◽  
Optimization Task ◽  
Feature Spaces ◽  
Nearest Neighbours ◽  
Monte Carlo Studies

An essential criterion for the proper implementation of case-control studies is selecting appropriate case and control groups. In this article, a new simulated annealing-based control group selection method is proposed, which solves the problem of selecting individuals in the control group as a distance optimization task. The proposed algorithm pairs the individuals in the n-dimensional feature space by minimizing the weighted distances between them. The weights of the dimensions are based on the odds ratios calculated from the logistic regression model fitted on the variables describing the probability of membership of the treated group. For finding the optimal pairing of the individuals, simulated annealing is utilized. The effectiveness of the newly proposed Weighted Nearest Neighbours Control Group Selection with Simulated Annealing (WNNSA) algorithm is presented by two Monte Carlo studies. Results show that the WNNSA method can outperform the widely applied greedy propensity score matching method in feature spaces where only a few covariates characterize individuals and the covariates can only take a few values.

The ‘well control’ artefact in case/control studies of specific psychiatric disorders

1989 ◽  
Vol 19 (3) ◽  
pp. 737-742 ◽  
Author(s):  
Sharon Schwartz ◽  
Bruce G. Link
Keyword(s):  
Risk Factor ◽  
Psychiatric Disorders ◽  
Group Selection ◽  
Case Control ◽  
Control Group ◽  
Case Control Studies ◽  
Suggested Approach ◽  
Well Control ◽  
Risk Factor Assessment ◽  
Intuitive Appeal

SynopsisAn appropriate choice of controls in case/control studies of specific psychiatric disorders is crucial for valid risk-factor assessment. One suggested approach to control-group selection, the use of a well control group, is the focus of this paper. While using well controls has intuitive appeal, this paper shows that such a procedure can lead to ambiguous and biased results.

Tryptophan-Niacin Metabolism in Rat with Puromycin Aminonucleoside-Induced Nephrosis

2006 ◽  
Vol 76 (1) ◽  
pp. 28-33 ◽  
Author(s):  
Yukari Egashira ◽  
Shin Nagaki ◽  
Hiroo Sanada
Keyword(s):  
Body Weight ◽  
Urinary Excretion ◽  
Enzyme Activities ◽  
Treated Group ◽  
Control Group ◽  
Puromycin Aminonucleoside ◽  
Low Level ◽  
Key Enzyme

We investigated the change of tryptophan-niacin metabolism in rats with puromycin aminonucleoside PAN-induced nephrosis, the mechanisms responsible for their change of urinary excretion of nicotinamide and its metabolites, and the role of the kidney in tryptophan-niacin conversion. PAN-treated rats were intraperitoneally injected once with a 1.0% (w/v) solution of PAN at a dose of 100 mg/kg body weight. The collection of 24-hour urine was conducted 8 days after PAN injection. Daily urinary excretion of nicotinamide and its metabolites, liver and blood NAD, and key enzyme activities of tryptophan-niacin metabolism were determined. In PAN-treated rats, the sum of urinary excretion of nicotinamide and its metabolites was significantly lower compared with controls. The kidneyα-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) activity in the PAN-treated group was significantly decreased by 50%, compared with the control group. Although kidney ACMSD activity was reduced, the conversion of tryptophan to niacin tended to be lower in the PAN-treated rats. A decrease in urinary excretion of niacin and the conversion of tryptophan to niacin in nephrotic rats may contribute to a low level of blood tryptophan. The role of kidney ACMSD activity may be minimal concerning tryptophan-niacin conversion under this experimental condition.

Haemostatic Clot Formation at Anastomosis of Synthetic Venous Graft in Defibrinogenated Dogs: A Scanning Electron Microscopic Study

1981 ◽  
Vol 45 (03) ◽  
pp. 276-281 ◽  
Author(s):  
S Ishimaru ◽  
E Berglin ◽  
H-A Hansson ◽  
A-C Teger-Nilsson ◽  
G William-Olsson
Keyword(s):  
Vena Cava ◽  
Treated Group ◽  
Control Group ◽  
Electron Microscopic ◽  
Scanning Electron Microscopic Study ◽  
Fibrin Network ◽  
Scanning Electron Microscopic ◽  
Expanded Polytetrafluoroethylene Graft ◽  
Morphological Differences ◽  
Scanning Electron

SummaryA segment of the inferior vena cava was replaced by an expanded polytetrafluoroethylene graft in 13 dogs. Five of them served as a control group, while the other 8 were moderately or severely defibrinogenated with subcutaneous batroxobin. Plasma fibrinogen decreased to extremely low values throughout the experiment in the defibrinogenated dogs except in the moderately treated group in which it temporarily rose to 0.72-0.87 g/1 on the first postoperative day.Scanning electron microscopic observations of the haemostatic clot formed at the anastomoses of the graft revealed no significant morphological differences in platelet adhesion and/or aggregation between the three groups. These findings confirmed that platelets play a key role in primary haemostasis during defibrinogenation.The fibrin network was slightly diminished and only short fibrin filaments could be seen in the moderately and severely defibrinogenated groups respectively. These differences in composition of the clots are discussed in relation to their haemostatic capacity.

Effects of oestradiol benzoate (OeB) and human chorionic gonadotrophin (hCG) on the testes and accessory sex glands of the rat

1981 ◽  
Vol 96 (2) ◽  
pp. 273-280 ◽  
Author(s):  
Mridula Chowdhury ◽  
Robert Tcholakian ◽  
Emil Steinberger
Keyword(s):  
Treated Group ◽  
Inhibitory Effect ◽  
Male Rats ◽  
Plasma Testosterone ◽  
Control Group ◽  
Intact Male ◽  
Intact Control ◽  
Testosterone Levels ◽  
Oestradiol Benzoate ◽  
Direct Inhibitory Effect

Abstract. It has been suggested that treatment of intact male rats with oestradiol benzoate (OeB) causes an interference with testosterone (T) production by the testes by a direct inhibitory effect on steroidogenesis. To test this hypothesis, different doses (5, 10 or 25 IU) of hCG were administered concomitantly with 50 μg of OeB to adult intact or hypophysectomized male rats. The testicular and plasma testosterone, and serum hCG levels were determined. The sex accessory weights were recorded. In the intact OeB-treated group of animals, hCG stimulated both the secondary sex organs and plasma testosterone levels above the intact control group. However, in hypophysectomized animals, although plasma testosterone levels increased above that of intact controls, their secondary sex organ weights did not. Moreover, inspite of high circulating hCG levels, the testicular testosterone content and concentration remained suppressed in OeB-treated animals. The reason for such dichotomy of hCG action on OeB-treated animals is not clear at present.

Evaluation of anti-psoriatic activity of selected phytochemicals on UV-induced psoriasis in mouse tail model

2020 ◽  
Vol 64 ◽  
pp. 123-128
Author(s):  
Jada Naga Lakshmi ◽  
A. Narendra Babu ◽  
Rama Rao Nadendla
Keyword(s):  
Disease Control ◽  
Ellagic Acid ◽  
Uv Light ◽  
Severity Index ◽  
Treated Group ◽  
Control Group ◽  
Standard Group ◽  
Significant Activity ◽  
Epidermal Thickness ◽  
Psoriasis Severity

Objectives: To evaluate anti-psoriatic activity of Phytochemicals on UV-Induced psoriasis in mouse tail model. Materials and Methods: Anti-psoriatic activity of selected phytochemicals on UV-Induced psoriasis in mouse tail model. The animals were dividing into 05 groups and each group contain 5 animals. Disease control group did not receive any treatment only exposure to UV-light, vehicle control treated with simple ointment, standard group treated with salicylic acid (1%w/w) ointment, remaining group are treated 1% and 2% selective phytochemical at two concentrations of ointment to topically on the tail skin. And the data were analysed using one way ANOVA followed by two-way ANOVA (Dunnett’s multiple comparisons test). Results: There was significant decrease in epidermal thickness (P < 0.05) as compared with control group. In 2% phytoconstituents has shown a significant reduction in the total epidermal thickness 8.4****±0.748, 7.6**±0.6781 and 8*±0.8366 in geraniol, glycyrrhizic acid and ellagic acid treated group, when compare to the disease induced animal, there was no lesion of Munro’s microabscess, capillary loop dilation along with elongation of rete ridges in the section of skin of rats. Psoriasis Severity Index was reduced in test treated groups as compared with that of disease control group. It was slowly reduced to 2nd week, totally (55-70%) reduction in PSI is observed at the time of third week of treatment period. Conclusion: The result of the study showed that the 2% of geraniol, ellagic acid, glycyrrhizicacid and hesperidin, exhibited significant activity on UV-induced psoriasis in rodents. The study implies that selected phytoconstituents are a promising research for further investigations to prove its anti-psoriatic activity.

Protective Effect of Moringa Oleifera Leaves Against TramadolInduced Nephrotoxicity in Mice

2017 ◽  
Vol 9 (02) ◽  
Author(s):  
Ashraf Albrakati
Keyword(s):  
Oral Dose ◽  
Moringa Oleifera ◽  
Treated Group ◽  
Control Group ◽  
Serum Urea ◽  
Kidney Function Tests ◽  
Mean Values ◽  
Intraperitoneal Dose ◽  
Moringa Oleifera Leaves ◽  
The Mean

Tramadol, a broadly in recent years, is an effective analgesic agent for the treatment of moderate to acute pain. Its metabolites are excreted by the kidney which may cause nephrotoxicity. Moringa oleifera leaves are commonly used to provide herbal and plant-derived medicinal products especially in developing nations. The present study was carried out to determine the biochemical and histopathological changes in the kidney of tramadol-treated albino mice and to evaluate the possible protective role of Moringa oleifera leaves against tramadol-induced nephrotoxicity. Twenty adult albino mice were divided into four groups. Control group (group i) received daily intraperitoneal injection of normal saline only, group ii received oral dose of Moringa oleifera leaves extract (20 mg/kg/bw) for three weeks, group iii received daily intraperitoneal dose of tramadol (0.3 mg/kg/bw) for the same period, group iv, received daily oral dose of Moringa oleifera leaves extract, (20 mg/kg/bw) three hours before injecting intraperitoneal dose of tramadol (0.3 mg/kg/bw), for the same period. Blood samples were withdrawn at the end of the experiment for kidney function tests and specimens from the kidney were processed for histological study. No significant differences in the mean values of the kidney function tests were noticed between Moringa oleifera group and control group. However, there was highly significant increase in the mean values of serum, urea and creatinine in tramadol-treated group as compared to the control group. Although tramadol + Moringa oleifera group revealed significant difference in the mean values of urea and creatinine when compared with tramadol-treated group. So, Moringa oleifera leaves extract have been shown to attenuate the renal dysfunction, improve the renal architecture, with nearly normalization of serum urea and creatinine levels which indicate improvement of renal function. In conclusion, in the light of biochemical results and histological findings, co-administration of Moringa oleifera leaves lessened the negative effects of tramadol-induced nephrotoxicity; possibly by its antioxidant action. Further investigation of these promising protective effects of Moringa oleifera leaves against tramadol-induced renal injury may have considerable impact on developing an adjunct therapy aiming to improve the therapeutic index of some nephrotoxic drugs.

POSSIBILITY TO REDUCE THROMBOCYTOPENIA AFTER CHEMORADIOTHERAPY IN ONCOLOGICAL PATIENTS

2017 ◽  
Vol 63 (3) ◽  
pp. 466-469
Author(s):  
Luiza Korytova ◽  
Aleksey Meshechkin ◽  
Oleg Korytov ◽  
V. Krasnikova
Keyword(s):  
Combined Treatment ◽  
Treated Group ◽  
Median Number ◽  
Blood Analysis ◽  
Control Group ◽  
Level Control ◽  
Normal Range ◽  
Oncological Patients ◽  
Level Increase ◽  
And Control

Objective was to establish efficiency of sodium nucleospermat in correcting thrombocytopenia after chemoradiotherapy in oncological patients. Methods and materials. The study included data on 32 patients that had undergone combined treatment from January till May 2016. After detecting thrombocytopenia patients were randomized into two groups (16 patients in each): treated group, where patients received sodium nucleospermat, and control group, where sodium nucleospermat was not used. Thrombocyte level control was done on 5th, 10th and 15th day after treatment was over. Results and discussion. All 16 patients showed positive dynamics in increasing thrombocyte level after Sodium nucleospermat injection course was finished. This was proven by first (5th day) blood analysis. On average thrombocyte level after sodium nucleospermat treatment has risen to normal, at 161х109/1. Only 3 patients from this group had to pause radiotherapy for 5 days. Control group patients, which did not receive sodium nucleospermat, showed evidence of thrombocyte level recovery by 10th day only. On average thrombocyte level increase was insignificant, and median number was 111*109/l. Low thrombocyte level was main reason to pause radiotherapy for 11 (69%) patients in control group. Conclusion. Sodium nucleospermat allowed raising thrombocyte level to the lower normal range, which surpassed by 40%-50% in control group patients. Use of sodium nucleospermat did not show any cases of allergic reactions, toxicity or complications in oncological patients.

Glacial Acetic Acid Catalyzed Synthesis, Physicochemical and Biological Evaluation of Benzodiazepines as Potent CNS Agents

2019 ◽  
Vol 19 (2) ◽  
pp. 146-151
Author(s):  
Vipin Kumar ◽  
Shweta Verma ◽  
Sushil Kumar
Keyword(s):  
Skeletal Muscle ◽  
Muscle Relaxant ◽  
Treated Group ◽  
Biological Evaluation ◽  
Log P ◽  
Control Group ◽  
Skeletal Muscle Relaxant ◽  
Benzodiazepine Derivatives ◽  
Chloro Group ◽  
Muscle Relaxant Activity

Background: Approach for green chemistry for chemical synthesis is found to be very efficient as it makes the reaction more easily, less tedious, maximize desired products and minimize by-products. Materials & Methods: Utilizing this approach 1, 5-benzodiazepines and its derivatives have been synthesized and evaluated for skeletal muscle and antianxiety activity. 1, 5-benzodiazepine derivatives have attracted great attention due to its diversity of pharmacological activities and its application in heterocyclic synthesis and medicines. The target compounds were synthesized by first reacting o-phenylenediamine with acetophenone to yield 1, 5-benzodiazepines. In the next step the NH of 1, 5-benzodiazepines were chloroacetylated and then the chloro group was substituted with different anilines. The structures were confirmed on the basis of their TLC, IR, 1H NMR and CHN elemental studies. The physicochemical parameters were determined for BBB penetration through online software. Results: The Log P values of the compounds tested showed that compounds have the potential to be CNS active. The compounds were evaluated for the skeletal muscle relaxant activity and antianxiety activity. It was investigated that 1, 5-benzodiazepines derivatives possess significant differences between control group and treated group. Conclusion: Among these derivatives, the compound bearing chloro group possesses the highest skeletal muscle relaxant and antianxiety activity.

Ethanol Extract of Achillea fragrantissima Enhances Angiogenesis through Stimulation of VEGF Production

2020 ◽  
Vol 21 ◽  
Author(s):  
Hana M. Hammad ◽  
Amer Imraish ◽  
Maysa Al-Hussaini ◽  
Malek Zihlif ◽  
Amani A. Harb ◽  
...  
Keyword(s):  
Wound Healing ◽  
Rural Communities ◽  
Ex Vivo ◽  
Ethanol Extract ◽  
Aortic Ring ◽  
Treated Group ◽  
Control Group ◽  
Dependent Manner ◽  
Achillea Fragrantissima

Objective: Achillea fragrantissima L. (Asteraceae) is a traditionally used medicinal herb in the rural communities of Jordan. Methods: The present study evaluated the efficacy of the ethanol extract of this species on angiogenesis in both, ex vivo using rat aortic ring assay and in vivo using rat excision wound model. Results: In concentrations of 50 and 100 µg/ml, the ethanol extract showed angiogenic stimulatory effect and significantly increased length of capillary protrusions around aorta rings of about 60% in comparison to those of untreated aorta rings. In MCF-7 cells, the ethanol extract of A. fragrantissima stimulates the production of VEGF in a dose-dependent manner. 1% and 5% of ethanol extract of A. fragrantissima containing vaseline based ointment was applied on rat excision wounds for six days and was found to be effective in wound healing and maturation of the scar. Both preparations resulted in better wound healing when compared to the untreated control group and vaseline-treated group. This effect was comparable to that induced by MEBO, the positive control. Conclusion: The results indicate that A. fragrantissima has a pro-angiogenic effect, which may act through the VEGF signaling pathway.

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