Physiological and molecular changes of onion (Allium cepa L.) seeds under different aging conditions.

BACKGROUND: Onion seeds have limited storage capacity compared to other vegetable seeds. It is crucial to identify the mechanisms that induce tolerance to storage conditions and reduce seed deterioration. To address this goal, an experiment was conducted to evaluate changes in germination, biochemical, physiological, and molecular characteristics of onion seed landraces (Horand, Kazerun landraces and Zargan cultivar) at different aging levels (control, three-days and six-days accelerated aging, and natural aging for one year). RESULTS: The findings suggest that there was an increase in glucose, fructose, total sugar, and electrolyte leakage in the Horand (HOR), Kazerun (KAZ) landraces, and Zarghan (ZAR) cultivar, with Kazerun exhibiting the greatest increase. The percentage and rate of germination of Kazerun decreased by 54% and 33%, respectively, in six-day accelerated aging compared to the control, while it decreased by 12% and 14%, respectively, in Horand. Protein content decreased with increasing levels of aging, with a decrease of 26% in Kazerun landrace at six days of aging, while it was 16% in Horand landrace. The antioxidant activities of catalase, superoxide dismutase, and glutathione peroxidase decreased more intensively in Kazerun. The expression of AMY1, BMY1, CTR1, and NPR1 genes were lower in Kazerun landraces than in Horand and Zargan at different aging levels. CONCLUSIONS: The AMY1, BMY1, CTR1, and NPR1 genes play a pivotal role in onion seed germination, and their downregulation under stressful conditions has been shown to decrease germination rates. In addition, the activity of CAT, SOD, and GPx enzymes decreased by seed aging, and the amount of glucose, fructose, total sugar and electrolyte leakage increased, which ultimately led to seed deterioration. Based on the results of this experiment, it is recommended to conduct further studies into the molecular aspects involved in onion seed deterioration. More research on the genes related to this process is suggested, as well as investigating the impact of different priming treatments on the genes expression involved in the onion seed aging process.

A drug utilization study of thiocolchicoside-containing medicinal products for systemic use in France and Italy: A cross-sectional electronic medical records database study.

PURPOSE: The risk minimization measures (RMM) for systemic use of thiocolchicoside (TCC) was implemented across Europe during 2014-2016. RMM included restriction of use in age <16 years, maximum dose and duration, chronic conditions, contraindication in pregnancy, lactation or in women of childbearing potential [WOCBP] without appropriate contraception. The current Drug Utilization Study was aimed to describe the prescribing practices of TCC in France and Italy. METHOD: The study analyzed data (demographic, prescription, diagnosis, and concomitant treatment) from electronic medical record databases. It compares drug utilization during pre-implementation (baseline: year 2013) and post-implementation (years 1, 2, and 3) of RMM. This study included panels of general practitioners (FGP) and rheumatologists (FRH) in France and Italy (IGP). RESULTS: TCC was largely prescribed as adjuvant therapy in both pre-implementation (FGP: 93.5%, FRH: 88.8%, IGP: 86.6%) and post-implementation (FGP: 92.3%, FRH: 89.5%, IGP: 89.0%) periods. Prescribing patterns were different in France and Italy, with FGP and FRH mainly prescribing oral formulation (>95% and >80%, respectively), while IGP prescribing intramuscular formulation (>70%). Prescriptions to patients aged ≥16 years were >99% in all panels during both periods. An improvement was observed in compliance with treatment duration for oral formulation in the FGP panel post-implementation versus pre-implementation (66.2% vs. 46.7%; p < 0.001). There was no change in prescription rate post RMM implementation in pregnant (FGP: 0.5%, IGP: 4.7%) and in WOCBP without appropriate contraception (FGP: 89.3%, IGP: 93.4%). CONCLUSION: These results highlighted changes in prescribing practices of TCC after RMM implementation, which varied across panels and measures.

Superior adaptation of aerobic rice under drought stress in Iran and validation test of linked SSR markers to major QTLs by MLM analysis across two years.

Drought is one of the biggest challenges for rice (Oryza sativa L.) production in rainfed areas. Developing "aerobic rice" cultivars could be a valuable alternative to irrigated/rainfed areas. During 2010-2013, 115 rice genotypes, including non-local cultivars and aerobic rice genotypes, were evaluated and 31 rice genotypes were screened, while 21 Iranian lowland rice cultivars (52 genotypes) were investigated under non-stress and drought conditions at the University of Guilan, Rasht, Iran, in 2014 and 2017. The results revealed the superiority of high yielding genotypes, namely Neda (6.202 t ha- 1), IR82639-B-B-140-1 (6.020 t ha- 1), and IR82635-B-B-82-2 (5.75 t ha- 1) under non-stress, Panda (4.512 t ha- 1), and IR82639-B-B-140-1 (4.08 t ha- 1), under drought stress conditions. Based on the molecular markers evaluation using identified SSR markers linked to major QTLs different important traits specially drought stress, IR 82639-B-B-140-1 showed the highest genetic distance with high-quality Iranian lowland cultivars, which could be considered as a donor for the development of new cultivars. Moreover, the assignment of rice genotypes based on Jaccard distance clustering was in agreement with the grouping of structure analysis. The validation test using MLM analysis in this natural population revealed the most important significant associations that were identified under drought conditions. These are: the associations between RM306, RM319, RM511, RM28166, and RM11943 with different grain yield (GY)-related traits simultaneously and stable across both years. These markers, which were verified in a natural population across 2 years, could be considered as the potential markers for use in marker-assisted breeding and to improve the grain yield of rice.

High soil and groundwater arsenic levels induce high body arsenic loads, health risk and potential anemia for inhabitants of northeastern Iran.

Arsenic bioavailability in rock, soil and water resources is notoriously hazardous. Geogenic arsenic enters the body and adversely affects many biochemical processes in animals and humans, posing risk to public health. Chelpu is located in NE Iran, where realgar, orpiment and pyrite mineralization is the source of arsenic in the macroenvironment. Using cluster random sampling strategy eight rocks, 23 soils, 12 drinking water resources, 36 human urine and hair samples and 15 adult sheep urine and wool samples in several large-scale herds in the area were randomly taken for quantification of arsenic in rock/soil/water, wool/hair/urine. Arsenic levels in rock/soil/water and wool/hair/urine were measured using inductively coupled plasma spectroscopy and atomic absorption spectrophotometry, respectively. While arsenic levels in rocks, soils and water resources hazardously ranged 9.40-25,873.3 mg kg(-1), 7.10-1448.80 mg kg(-1) and 12-606 µg L(-1), respectively, arsenic concentrations in humans' hair and urine and sheep's wool and urine varied from 0.37-1.37 µg g(-1) and 9-271.4 µg L(-1) and 0.3-3.11 µg g(-1) and 29.1-1015 µg L(-1), respectively. Local sheep and human were widely sick and slightly anemic. Hematological examination of the inhabitants revealed that geogenic arsenic could harm blood cells, potentially resulting in many other hematoimmunological disorders including cancer. The findings warn widespread exposure of animals and human in this agroecologically and geopolitically important region (i.e., its proximity with Afghanistan, Pakistan and Turkmenistan) and give a clue on how arsenic could induce infectious and non-infectious diseases in highly exposed human/animals.

Effects of buprenorphine on balance of oxidant/antioxidant system in the different ages of male rat liver.

Our knowledge about a link between buprenorphine and hepatotoxicity is controversial. This study evaluated the effects of buprenorphine on the liver of young, adult, and aged rats. For this reason, young, adult, and aged rats received intraperitoneally 0.25, 0.5, and 1 mg/kg buprenorphine for 30 days. The present results revealed that the normal aging was associated with a significant decrease in the activities of antioxidant enzymes, and an increase in the liver lipid peroxidation, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) activities in the aged rats. This study also demonstrated that buprenorphine led to a significant increase in the serum activities of ALT, AST, and LDH as well as liver lipid peroxidation content with a decrease in the antioxidant enzymes in the liver of buprenorphine-treated aged rat versus the aged matched control animals. In conclusion, the present results demonstrate that buprenorphine deteriorated oxidative damage in the aged livers.

Effectiveness of a clinical protocol implemented to standardize snakebite management in Iran: initial evaluation.

OBJECTIVE: This study was designed to evaluate the effectiveness of a new protocol implemented to standardize snakebite management in Iran. METHODS: In this study, 27 patients treated according to the new protocol in 2012 (P+) were compared with 22 patients treated according to the previous modality in the year before implementation of the protocol (P-) in Mashhad Medical Toxicology Centre (MTC). Demographic characteristics and treatment details of all patients were recorded prospectively. Envenomation severity of each victim was assessed according to snakebite severity score (SSS). RESULTS: After implementation of the protocol, a smaller percentage of patients received antivenom (AV) therapy (78% vs 95%; P=.079). In spite of no significant difference in baseline severity of envenomation between the 2 groups (SSS [mean±SD], 34.8±18.1 vs 35.5±17.4; P=.801), the P+ group received significantly fewer AV vials (8.4±6.8 vs 12.1±5.6 vials; P=.042) and had a significantly shorter length of hospital stay (2.2±1.5 vs 3.2±1.8 days; P=.027). Moreover, smaller proportion of P+ patients experienced recurrence of venom-induced effects; however, the difference was not significant (18.5% vs 36%; P=.159). The reduction in use of antiallergy treatments to prevent or treat acute hypersensitivity reactions approached statistical significance (41% vs 68%; P=.051). These findings denote a reduction in AV use of approximately 4 vials and a reduction in hospital stay of 1 day for each patient, which translates to approximately $196/patient in healthcare cost savings. CONCLUSIONS: Implementation of a snakebite management protocol at MTC reduced overall antivenom usage, use of antiallergy interventions, and length of hospital stay.

Rhabdomyolysis in 114 patients with acute poisonings.

BACKGROUND: Rhabdomyolysis is a clinical and biochemical syndrome, which is observed in some patients with acute chemical and/or pharmaceutical poisonings. We aimed to investigate rhabdomyolysis in patients with acute poisonings due to different chemicals, natural toxins or drug overdose. MATERIALS AND METHODS: Following approval of the University medical research committee and obtaining informed consents from the patients or their relatives, all patients with acute poisonings who were treated between March 2009 and February 2010 in the Toxicologic Ward of Imam Reza Hospital and had serum creatine phosphokinase (CPK) above 975 IU/L (as a definition for rhabdomyolysis) were studied. RESULTS: Of 3555 hospitalized poisoned patients, 114 patients had rhabdomyolysis with CPK of 5996 ± 892 IU/L (mean ± standard error). The most common intoxication to induce the rhabdomyolysis was opioid overdose (28%). Acute renal failure (ARF) was diagnosed in 11 (8.7%) patients. There was a linear correlation between CPK and creatinine (P < 0.001), which in turn had a significant correlation with death (P < 0.05). CONCLUSION: Patients with acute poisoning were at risk of rhabdomyolysis. Acute opioid poisoning was the most common cause of toxic rhabdomyolysis in the intoxicated patients, and ARF was the main complication.

Smoking crushed hyoscine/scopolamine tablets as drug abuse.

BACKGROUND: Hyoscine N-butyl bromide/scopolamine (H/S) is a type of anticholinergic agent that is commonly used as an antispasmodic drug. We have evaluated the effects of crushed H/S smoking in prisoners who illicitly abused this drug. METHODS: All imprisoned cases with at least a 3-month history of HS were evaluated from April 2012 to September 2012. Demographic information, history, and clinical findings were studied. RESULTS: In total, 36 male cases with a mean (SD, min-max) age of 33.3 (3.6, 27-42) years were included. All subjects were cigarette smokers with a history of substance abuse and were under Methadone Maintenance Therapy (MMT). The majority (75%) of participants smoked H/S tablet with pin, and others used aluminum foil. Hallucinations were the most common neurological features. Amnesia (88%), insomnia (83%), palpitation (86%), flushing (86%), irritability (94%), and inability to concentrate (91%) were the most common findings. Among them, auditory (61%), visual (72%), and tactile (72%) hallucinations were reported. CONCLUSIONS: This is the first case study of hyoscine smoking abuse. We found that H/S acts similar to other hallucinogens. Concurrent abuse of H/S in cases under MMT could be a future trend of abuse. Clinicians should be aware of abuse potential of H/S in treatment of some patients for drug overdose.

Evaluation of lung and bronchoalveolar lavage fluid oxidative stress indices for assessing the preventing effects of safranal on respiratory distress in diabetic rats.

We investigated the effects of antioxidant activity of safranal, a constituent of Crocus sativus L., against lung oxidative damage in diabetic rats. The rats were divided into the following groups of 8 animals each: control, diabetic, and three diabetic + safranal-treated (0.25, 0.50, and 0.75 mg/kg/day) groups. Streptozotocin (STZ) was injected intraperitoneally (i.p.) at a single dose of 60 mg/kg for diabetes induction. Safranal was administered (i.p.) from 3 days after STZ administration to the end of the study. At the end of the 4-week period, malondialdehyde (MDA), nitric oxide (NO) and reduced glutathione (GSH) contents, activity of superoxide dismutase (SOD), and catalase (CAT) were measured in the bronchoalveolar lavage fluid (BALF) and lung tissue. Safranal in the diabetic groups inhibited the level of MDA and NO in BALF supernatant and lung homogenate. The median effective dose (ED50) values were 0.42, 0.58, and 0.48, 0.71 mg/kg, respectively. Safranal in the diabetic groups increased the level of GSH and the activity of CAT and SOD in BALF supernatant and lung homogenate. The ED50 values were 0.25, 0.33, 0.26 in BALF and 0.33, 0.35, 0.46 mg/kg in lung, respectively. Thus, safranal may be effective to prevent lung distress by amelioration oxidative damage in STZ diabetic rats.

Evaluation of the effect of diacetyl morphine on salivary factors and their changes after methadone therapy.

OBJECTIVES: Psychoactive drugs are responsible for pathological changes in the mouth including dental caries, which most troublesome. The aim of the present study was to evaluate the effect of heroin on several salivary factors which are involved in the oral health and their changes after methadone maintenance therapy (MMT). MATERIALS AND METHODS: Forty patients with heroin abuse history, who referred to Imam Reza Hospital for MMT were included. Saliva sampling was carried out two times; at the first visit (time 1) and repeated 1 month after MMT (time 2). The saliva was analyzed immediately to evaluate the total volume, Ph, CPR, the Uric acid concentration, nitric oxide and antioxidant capacity. RESULTS: The mean values for saliva volume, pH, CRP, Uric acid, antioxidant and nitric oxide were 0.38 ± 0.14, 7.63 ± 1.22, 5.2 ± 2.3, 1.47 ± 0.8, 0.80 ± 0.23, and 0.26 ± 0.03, respectively at first visit and 0.34 ± 0.22, 7.37 ± 1.01, 6.1 ± 2.6, 2.18 ± 0.9, 0.74 ± 0.3 and 0.29 ± 0.08 after 1 month of MMT. These values are below the normal ranges; however, there was no significant difference between two times in term of saliva volume, pH and saliva component (p > 0.05). CONCLUSION: Heroin addiction changed the effective salivary factors and therefore could negatively contribute to oral health. These factors were not return to the normal range after 1 month of MMT. Physicians should be informed about focusing on oral health in patients under MMT.

Snakebite management in Iran: Devising a protocol.

BACKGROUND: Snakebite in Iran has been a health concern. However, management of snakebite is not standardized and varies from center to center. This study is aimed at devising an evidence-based comprehensive protocol for snakebite management in Iran, to reduce unnecessary variations in practice. MATERIALS AND METHODS: A narrative search in electronic databases was performed. Fifty peer-reviewed articles, guidelines, and textbooks were reviewed and practical details were extracted. Our currently used protocol in the Mashhad Toxicology Center was supplemented with this information. Consequently an improved wide-range protocol was developed. The protocol was then discussed and amended within a focus group comprised of medical toxicologists and internal medicine specialists. The amended version was finally discussed with expert physicians specialized in different areas of medicine, to be optimized by supplementing other specific considerations. RESULTS: During a one-year process, the protocol was finalized. The final version of the protocol, which was designed in six steps, comprised of three components: A schematic algorithm, a severity grading scale, and instructions for supportive and adjunctive treatments. The algorithm pertains to both Viperidae and Elapidae snakebite envenomations and consists of a planned course of action and dosing of antivenom, based on the severity of the envenomation. CONCLUSION: Snakebite envenomation is a clinical toxicologic emergency, which needs to be treated in a timely and organized manner. Hence, a multi-aspect protocol was designed to improve the clinical outcomes, reduce unnecessary administration of antivenom, and help physicians make more proper clinical judgments.

The effect of lead acetate on oxidative stress and antioxidant status in rat bronchoalveolar lavage fluid and lung tissue.

Despite the wide spread of lead environmental pollution, the effect of this heavy metal on respiratory disease was not shown yet. In respect to increased oxidative stress is an important mechanism in the pathogenesis of respiratory disease, the present study was designed to examine the association between lead toxicity and lung disease via measuring oxidative stress biomarkers in bronchoalveolar lavage fluid (BALF) and lung tissue of rat. For this aim, 32 rats were divided into the following groups of eight animals each: control, three lead tested (received lead acetate in the drinking water for a period of 14 d at concentrations of 250, 500 and 1000 ppm) groups. At the end of the 2 week period, malondialdehyde (MDA), nitric oxide (NO) and reduced glutathione (GSH) contents were measured to assess free radical activity in the BALF and lung tissue. Superoxide dismutase (SOD) was also determined. A significant dose-dependent increase in the BALF supernatant and lung homogenate levels of MDA and NO with decrease GSH level and SOD activity were observed in the lead-treated groups compared with the control group (p < 0.05). Thus, lead acetate may be contributed to respiratory disorders via increased oxidative stress.

Metal concentrations in marine fishes collected from Hara biosphere in Iran.

The metal levels (Hg, As, Cu, and Zn) in tissues of edible fish species (Pampus argenteus, Sillago sihama, Liza klunzingeri and Platycephalus indicus) were evaluated. The metal concentrations were found to follow the order: liver > kidney > gill > muscle, except for Zn from P. argenteus showing an inversion of liver and kidney. Generally, the benthic species (P. indicus and S. sihama) showed a marked potential for tolerating high metal levels. Significant negative correlations were found between fish size/age and metals concentration in the most organs. The element levels in the muscles were lower than the maximum allowable concentrations, except for mercury in S. sihama and P. indicus.

Pattern of illicit drug use in patients referred to addiction treatment centres in Birjand, Eastern Iran.

OBJECTIVE: To evaluate the pattern of use of opioid and other illegal drugs in patients seeking addiction treatment in Birjand, eastern Iran. METHODS: The prospective study was conducted from March 21, 2009 to March 21,2010, and comprised all patients referred to the seven addiction treatment centres in Birjand. Data was obtained through pre-designed questionnaires and it was analysed using SPSS 16. RESULTS: Of the 700 substance users referred to the 7 centres and who volunteered to participate, 632 (90.3%) were males and 68 (9.7%) were females. The male/female ratio was approximatly 9.3/1. Mean age was 34+/-10.2 (range: 10-75) years. The type of drugs used included traditional drugs (n= 342; 48.9%) and newer modern drugs (n=314; 44.9 %). The mean age of the first experience with drugs was 21.91+/-7.1 (range=0-60) years. There was significant different between the type of drugs used and the place of residence (p<0.019), age (p<0.0001), martial status (p<0.0001), occupation (p<0.006) and education (p<0.017). CONCLUSION: The prevalence of illicit drug addiction was quite high. There seemed to have been a change in the pattern of drug use and in the type of illegal drugs used in the study area, from traditional drugs to new and modern drugs. As such, identifying risk factors related to addiction and the prevention of addiction should be one of the most important health priorities for the authorities.

Chlordiazepoxide preventive effect on tramadol overdose induced serotonin syndrome evaluated by hunter and radomski criteria: a clinical trial.

INTRODUCTION: Tramadol is an analgesic medication that is frequently abused. It has two functions; mu-opioid receptors agonism, as well as, serotonergic activities. It has shown that tramadol overdose may induce serotonin syndrome (SS). This study evaluates whether early treatment with chlordiazepoxide could prevent SS in admitted tramadol overdoses. MATERIALS AND METHODS: In this single blind randomized control trial, 50% of admitted tramadol overdoses in Imam Reza (p) Hospital from 21 September 2011 to 21 January 2012 were recruited. Cases received chlordiazepoxide and controls received placebo. Clinical findings were recorded in a pre-designed spread sheet every 6 hours in the first 24 hours of admission. SS was determined by two independent methods; Hunter Criteria (HC) and Radomski Criteria (RC). RESULTS: In total, five patients developed SS when HC or RC was taken into account. Among them, four cases were shared. None of the SS cases diagnosed with HC received chlordiazepoxide. However, just one SS case diagnosed with RC was from the case group. Based on HC, chlordiazepoxide decreased the Risk Ratio (CI 95%) of SS to 0.80 (0.66-0.97) (P = 0.025). This effect did not reach statistically significant levels when SS was diagnosed with RC. CONCLUSION: This study supports the fact that pre-treatment with chlordiazepoxide could prevent tramadol overdose induced SS.

DELAY OF GERMINATION 1 (DOG1) regulates dormancy in dimorphic seeds of Xanthium strumarium.

Seed dormancy ensures plant survival but many mechanisms remain unclear. A high-throughput RNA-seq analysis investigated the mechanisms involved in the establishment of dormancy in dimorphic seeds of Xanthium strumarium (L.) developing in one single burr. Results showed that DOG1 , the main dormancy gene in Arabidopsis thaliana L., was over-represented in the dormant seed leading to the formation of two seeds with different cell wall properties. Less expression of DME /EMB1649 , UBP26 , EMF2, MOM, SNL2, and AGO4 in the non-dormant seed was observed, which function in the chromatin remodelling of dormancy-associated genes through DNA methylation. However, higher levels of ATXR7 /SDG25, ELF6 , and JMJ16/PKDM7D in the non-dormant seed that act at the level of histone demethylation and activate germination were found. Dramatically lower expression in the splicing factors SUA, PWI , and FY in non-dormant seed may indicate that variation in RNA splicing for ABA sensitivity and transcriptional elongation control of DOG1 is of importance for inducing seed dormancy. Seed size and germination may be influenced by respiratory factors, and alterations in ABA content and auxin distribution and responses. TOR (a serine/threonine-protein kinase) is likely at the centre of a regulatory hub controlling seed metabolism, maturation, and germination. Over-representation of the respiration-associated genes (ACO3 , PEPC3 , and D2HGDH ) was detected in non-dormant seed, suggesting differential energy supplies in the two seeds. Degradation of ABA biosynthesis and/or proper auxin signalling in the large seed may control germinability, and suppression of endoreduplication in the small seed may be a mechanism for cell differentiation and cell size determination.

Profiling "Success": Demographic and Personality Predictors of Effective Peer Leaders in a Diabetes Self-management Intervention.

BACKGROUND: The sociodemographic and personality profiles of effective peer leaders in the context of diabetes self-management interventions are poorly understood. In this study, we explored the demographic and personality characteristics of peer leaders participating in a 12-month, telephone-based type 2 diabetes self-management intervention. METHODS: We used a sequential explanatory mixed-methods research design and recruited 52 peer leaders. Thirty-seven peer leaders had at least 1 participant complete both the baseline and the 12-month assessments. Eligible peer leader candidates were English-speaking adults (≥21 years of age) with diabetes and a self-reported glycated hemoglobin (A1C) level of ≤8% who had access to a phone and transportation and were willing to attend a 30-hour training program. Peer leaders completed a self-report survey assessing sociodemographic characteristics and a Mini-International Personality Item Pool scale measuring the "Big 5" personality traits. After the intervention, 17 peer leaders participated in semistructured interviews on their program experience. We categorized peer leaders as effective if their participants sustained or improved their A1C and diabetes distress (DD) scores from baseline to 12 months, and as ineffective if their participants worsened on any of these parameters. RESULTS: Our cohort scored highest on agreeableness and lowest on neuroticism. Twenty peer leaders were considered effective, most of whom were male, married, employed and educated. They also had significantly lower mean DD levels (p=0.02) and a higher extroversion score (p=0.03) at baseline. CONCLUSIONS: Extroversion emerged as the best personality predictor of peer leader effectiveness. These results, in combination with interview responses, were used to produce a peer leader selection model.

Bioavailability of rectal acetaminophen in children following anorectal surgery.

BACKGROUND: Acetaminophen is widely used as an analgesic and antipyretic agent in pediatrics. Although bioavailability of rectal acetaminophen is unpredictable, rectal route is a usual and acceptable method of prescription. Major anorectal surgery may alter the normal structure of the surgical site, especially the vascular elements and the normal connections between port and systemic vessels. As a result the pharmacokinetics of rectal medications might also be altered. Based on this hypothesis, we decided to study acetaminophen plasma concentration among children who underwent these types of surgeries to determine the pharmacokinetic of absorption, plasma concentration, safety, and efficacy of rectal acetaminophen. MATERIALS AND METHODS: The study included 20 cases with previous history of pull-through procedure owing to Hirschsprung's disease (HD), 20 cases with imperforate anus (IA) reconstructive surgeries who were admitted for colostomy closure, and 20 otherwise healthy cases of inguinal herniotomy. Venus blood sampling was done 4, 8 and 12 hrs after a single loading dose of rectal acetaminophen (40 mg/kg), and plasma acetaminophen concentration was compared between groups. RESULTS: Mean serum acetaminophen levels of the HD group were significantly higher than those of the herniotomy group (36.3 ±â€¯6.79, 27.4 ±â€¯8.42, 16.8 ±â€¯7.62 versus 25.9 ±â€¯9.12, 16.7 ±â€¯6.74, 8.1 ±â€¯5.79 (µg/ml) at 4, 8 and 12 hrs after drug administration and P < 0.05). The IA group had higher concentrations of plasma acetaminophen compared to the herniotomy group; however, the p values were not statistically significant. (31.4 ±â€¯10.39, 21.5 ±â€¯9.12, 13.3 ±â€¯6.79 versus 25.9 ±â€¯9.12, 16.7 ±â€¯6.74, 8.1 ±â€¯5.79 (µg/ml) at 4, 8 and 12 hrs after drug administration). Serum concentrations of acetaminophen in IA and HD patients were above the therapeutic range four hours after administering the loading dose (31.4 ±â€¯10.39 and 36.3 ±â€¯6.79 versus 5-20 µg/ml). CONCLUSION: Bioavailability of rectal acetaminophen might get altered after major anorectal surgery in children. Rectal acetaminophen should be administered with special caution among infants with history of anorectal operations. Repeated dose of rectal acetaminophen may cause the drug blood concentration to reach toxic levels in these patients. TYPE OF STUDY: Prospective comparative study. LEVEL OF EVIDENCE: Level II.