scholarly journals The effect of ivermectin® on fertility, fecundity and mortality of Anopheles arabiensis fed on treated men in Ethiopia

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Wondemeneh Mekuriaw ◽  
Meshesha Balkew ◽  
Louisa A. Messenger ◽  
Delenasaw Yewhalaw ◽  
Adugna Woyessa ◽  
...  

Abstract Background Insecticide resistance is a growing threat to malaria vector control. Ivermectin, either administered to humans or animals, may represent an alternate strategy to reduce resistant mosquito populations. The aim of this study was to assess the residual or delayed effect of administering a single oral dose of ivermectin to humans on the survival, fecundity and fertility of Anopheles arabiensis in Ethiopia. Methods Six male volunteers aged 25–40 years (weight range 64–72 kg) were recruited; four of them received a recommended single oral dose of 12 mg ivermectin and the other two individuals were untreated controls. A fully susceptible insectary colony of An. arabiensis was fed on treated and control participants at 1, 4, 7, 10 and 13 days post ivermectin-administration. Daily mosquito mortality was recorded for 5 days. An. arabiensis fecundity and fertility were measured from day 7 post treatment, by dissection to examine the number of eggs per mosquito, and by observing larval hatching rates, respectively. Results Ivermectin treatment induced significantly higher An. arabiensis mortality on days 1 and 4, compared to untreated controls (p = 0.02 and p < 0.001, respectively). However, this effect had declined by day 7, with no significant difference in mortality between treated and control groups (p = 0.06). The mean survival time of mosquitoes fed on day 1 was 2.1 days, while those fed on day 4 survived 4.0 days. Mosquitoes fed on the treatment group at day 7 and 10 produced significantly lower numbers of eggs compared to the untreated controls (p < 0.001 and p = 0.04, respectively). An. arabiensis fed on day 7 on treated men also had lower larval hatching rates than mosquitoes fed on days 10 and 13 (p = 0.003 and p = 0.001, respectively). Conclusion A single oral dose of ivermectin given to humans can induce mortality and reduce survivorship of An. arabiensis for 7 days after treatment. Ivermectin also had a delayed effect on fecundity of An. arabiensis that took bloodmeals from treated individuals on day 7 and 10. Additional studies are warranted using wild, insecticide-resistant mosquito populations, to confirm findings and a phase III evaluation among community members in Ethiopia is needed to determine the impact of ivermectin on malaria transmission.

2002 ◽  
Vol 14 (1) ◽  
pp. 29 ◽  
Author(s):  
Clive A. Marks ◽  
Marian Brzozowski ◽  
Hieronim Zurek ◽  
Malcolm Clark

Single oral doses of 100 g kg–1 cabergoline (CAB) were previously found to affect the reproductive success of silver fox (Vulpes vulpes) vixens from Day 28 post insemination (PI) onwards by causing abortions and postnatal mortality. The present trial investigated the effect of a single oral dose of 100 g kg–1 CAB given to farmed silver fox vixens at 7, 14, 21 or 28 days PI. Six vixens were dosed with CAB at each day PI and abortions, total post-partum litter loss and the combined effects of both were compared with a group of vixens that received a placebo and a control group of vixens that received no treatment. No significant difference existed between the placebo and control groups in the incidence of abortion, postnatal litter loss and litter size at 3 weeks post partum. Overall, a significantly higher frequency of abortions were detected in vixens dosed with CAB (6/24) compared with the combined placebo and control (0/41) groups (P<0.01). Cabergoline administration was significantly associated with complete litter loss (P<0.01) and the combined effects of abortion and litter loss (P<0.001). Oral CAB significantly reduced the reproductive success of vixens when given at Day 21 and Day 28 PI, but not at Day 7 and Day 14 PI.


2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 83-84
Author(s):  
Prakash Poudel ◽  
Crystal L Levesque ◽  
Ryan S Samuel ◽  
Benoit St- Pierre

Abstract While a number of approaches have been developed to counter intestinal dysfunction and reduced growth during the early post-weaning period, there is a need for improvement or development of new feed additives. A trial was performed to evaluate the impact of dietary inclusion of a peptide-based commercial product (Peptiva, Vitech Biochem Corp) on the growth and fecal microbiome of nursery pigs. A total of 746 weaned pigs (5.9 ± 0.1 kg) divided between 15 control (standard nursery diet) and 15 treatment pens (control diet with Peptiva at 1, 0.5, and 0.3%, for each respective phase) received their assigned diets for 6 wks (Phase I: d0 – 7; Phase II, d8 – 21; Phase III, d22 – 42). No significant difference in body weight, daily gain, daily feed intake or gain:feed was observed between control and treatment animals (P > 0.05). Microbiome analysis was conducted using 10 fecal samples collected at the end of Phase II and 10 samples at the end of Phase III. Bacterial composition was assessed by Operational Taxonomic Unit (OTU) clustering of sequence data generated from PCR amplicons targeting the V1-V3 region of the bacterial 16S rRNA gene. Eleven OTUs were found to vary in abundance between Control Phase II and Control Phase III (P < 0.05), indicating a base diet effect on bacterial composition. Three OTUs were in lower abundance in Peptiva Phase II samples compared to Control Phase II (P < 0.05), but no significant difference was observed in the abundance of these three OTUs when comparing Peptiva Phase II to Control Phase III (P > 0.05). No OTUs differed in abundance between Peptiva Phase III and Control Phase III samples. These results suggest that Peptiva can modulate the composition of the swine microbiome during a specific window of the nursery stage, potentially by accelerating its maturation.


SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A180-A181
Author(s):  
Mustafa Jafri ◽  
Gabrielle Rosa-Acosta ◽  
Jose Flores Martinez ◽  
Elizabeth Schofield ◽  
Cy Wilkins ◽  
...  

Abstract Introduction Untreated polycythemia leads to complications including thrombosis. Obstructive sleep apnea (OSA) is commonly associated with secondary erythrocytosis, which testosterone therapy can perpetuate. Effects of positive airway pressure (PAP) on elevated hematocrit (HCT) is unknown. We hypothesize PAP adherence can reduce HCT in men with OSA and polycythemia. Methods Retrospective chart review of male outpatients with newly diagnosed OSA and HCT≥45% at or 3 months before polysomnography (PSG) was conducted. Intervention group consisted of patients initiating PAP for OSA. HCT within 6 months of PAP initiation and PSG were recorded for intervention and control groups, respectively. Primary endpoint was time-to-HCT reduction of HCT&lt;50% plus 3% decrease. Cox proportional-hazards analysis was used to assess time-to-HCT response. Demographics, smoking history, testosterone administration, STOP-Bang score, AHI, and PAP compliance data were obtained. Patients excluded if PAP not indicated, or if PSG, PAP compliance, or repeat HCT were unavailable. Results 41 men with OSA had HCT≥45%, of which 16 had HCT≥50%. Median age was 60 years and median BMI was 32 kg/m2. 28 started PAP. 21 met definition for PAP compliance within 6 months. Median AHI of intervention and control groups were 23 and 19 events/hr, respectively. Mean baseline HCT of both groups were 49 and 50, respectively. No significant difference in age, BMI, smoking history, testosterone therapy, and baseline HCT between both groups noted. 39% of intervention group exhibited HCT response at 1 or more longitudinal assessments, versus 38% of control. Intervention group had higher mean STOP-Bang than control (mean 5.9 vs. 4.6, p=0.01) and trended towards higher mean baseline AHI (27.4 vs. 19.0, p= 0.06). Time-to-event analysis controlling for STOP-Bang and AHI demonstrated PAP was not associated with time-to-HCT response (HR = 1.3, 95% CI = 0.4–4.4). In moderate-severe OSA patients, 40% of intervention group had HCT response compared to 14% of control, though difference was not significant (HR = 2.5, 95% CI = 0.3–20.0). Conclusion Moderate-severe OSA patients trended towards reduction in HCT with PAP, although not statistically significant. Testosterone administration did not affect HCT response to PAP in this cohort. Larger studies are required to determine HCT response to PAP in these patients. Support (if any):


Nutrients ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1545 ◽  
Author(s):  
Lily Ding ◽  
Nazimah Hamid ◽  
Daniel Shepherd ◽  
Kevin Kantono

More people working at offices are choosing to eat meals at their desks, making “desktop dining” an increasingly common phenomenon. Previous studies have reported that environmental distractors, such as television viewing, can influence meal intake and subsequent snack intake. However, the impact of stressful mental tasks on eating behavior has received relatively less attention, focusing only on subsequent meal intake or concurrent snack intake. This study sets out to determine whether eating while working influenced current meal energy intake. This research also examined the relationship between dietary restraint status and energy intake. A crossover experimental design was employed requiring participants (14 males and 29 females) to eat pizza quietly and at rest (control), and while working on a computer (work). Measurements included BMI, energy intake, state anxiety, restrained eating behavior, stress levels (pre- and post-eating), and appetite (before and after both work and control sessions). The findings showed that consuming food while working on a computer significantly increased stress but had no influence on energy intake compared to the control condition. However, post-eating hunger levels were significantly higher in the work condition compared to the control condition. As expected, satiety levels decreased significantly from pre- to post-eating for both work and control conditions. In addition, no significant relationship was observed between restrained eating behavior and energy intake in both work and control conditions. These results suggest that eating while working affected satiety of normal weight participants, as indicated by the significant difference in post-meal satiety levels between work and control conditions.


2021 ◽  
Author(s):  
Vildan Güngörer ◽  
Mehmet Öztürk ◽  
Mustafa Yasir Özlü ◽  
Şükrü Arslan

ABSTRACT Objectives Long-term therapy with low-dose methotrexate (MTX) is widely used in treatment of rheumatic diseases, in children. The purpose of this study was to evaluate liver elasticity in patients with juvenile idiopathic arthritis (JIA) who received MTX and compare the results with control group. Methods Liver elasticity was evaluated with shear wave elastography (SWE) technique in 25 patients aged 3–17 years who were followed up with JIA and received MTX and compared with 25 healthy controls of the same age and weight. Factors that had an effect on liver elasticity were examined. Results The mean SWE value of patients was 2.64 ± 2.13 m/s and 24.10 ± 18.50 kPa, whereas 1.83 ± 0.16 m/s and 10.09 ± 1.83 kPa in control group. There was a significant difference in liver elasticity in the patient and control groups. When the patients were evaluated as Group 1 (&lt; 1000 mg) and Group 2 (≥ 1000 mg) according to the cumulative MTX dose, no significant difference was obtained. There was positive correlation between liver elasticity and weekly MTX dose and age. Conclusions Our study revealed that liver elasticity significantly decreased in patients who received MTX when compared with the control group. The elastography technique will be understood better over time and used safely in many areas.


2017 ◽  
Vol 8 (3) ◽  
pp. 172
Author(s):  
Waqar Ahmad ◽  
Zuraina Ali ◽  
Muhammad Aslam Sipra ◽  
Imtiaz Hassan Taj

Smartboards, which are now widely used in the teaching and learning process in Saudi Arabia, have turned the traditional environments of the classrooms, especially the EFL classrooms to be more interesting and encouraging. Literature reviews suggest that Saudi students usually lack motivation for studying English as a foreign language. This study tends to investigate the impact of Smartboards on preparatory year EFL learners motivation at a Saudi university. Two intact groups were selected, in which one was termed as experimental and the second as control group. The experimental group was taught using the Smartboard while the control group was taught with the traditional whiteboard, pen and book method. The treatment was given for seven weeks. A questionnaire was administered to both the groups at the beginning and the end of the study. The data was analysed using the SPSS and the results showed that there was significant difference between the experimental and control groups in terms of motivation.  


Author(s):  
Abdul Latif Al-Zakri

This study aimed to examine the impact of the use of self-questioning in the understanding of fifth grade students in mathematics material. The researcher used the experimental methodology for independent groups to investigate the impact of the independent variable, which is a self-questioning strategy on the dependent variable, which is understanding. The study sample consisted of 42 students from the fifth grade students from Khubayb bin Udai School in Riyadh; equally divided into two groups of 21 students in each group (experimental and control), and after making sure from groups' equivalence by applying the tools of the study, having been taught the experimental group by using self-questioning strategy, while the control group has been studied the unit by using the traditional method. After the completion of the study of prescribed content study, study tools (achievement test) were applied then. The results indicated to the presence of a statistically significant difference (at the significance level <0. 05) between the mean scores of the two groups' students (experimental and control) in achievement test posttest for the experimental group. Since the results of the study were positive in increasing the achievement, the researcher recommended the need to use self-questioning to raise the level of achievement of learners in mathematics material


2019 ◽  
Vol 147 (3-4) ◽  
pp. 199-204
Author(s):  
Maja Davidovic ◽  
Jadranka Otasevic ◽  
Nada Dobrota-Davidovic ◽  
Ivana Petronic ◽  
Dragomir Davidovic ◽  
...  

Introduction/Objective. The development of speech is the result of interaction of different systems of the cortex, which gradually acquires the ability of phonological presentation and motor control, in the presence of a series of physical and physiological changes in the morphology of the articulation system. The objective of the study was to examine the impact of laterality and cortical responses on the development of speech in children. Methods. Research is a quasi-experimental design with two groups. The sample covered 60 children from Belgrade, of both sexes, ages 5.5?7 years, divided into two groups, experimental (30) and control (30). We used the following instruments: test for assessing laterality and ascertaining evoked potentials. Results. On the visual lateralization subtest there was a statistically significant difference (?2 = 7.56, p < 0.05) between the observed groups. The visual evoked potentials on all measured parameters gave a statistically significant difference between the groups: waveform cortical responses ? left (?2 = 30.00, df = 1, p < 0.05); cortical responses ? right (?2 = 6.667, df = 1 , p < 0.05); waveform amplitude ? left (?2 = 13.469, df = 1, p < 0.05); amplitude ? right (?2 = 40.00, df = 1, p < 0.05), somatosensory potentials (?2 = 18.261, df = 1, p <0.05); waveform amplitude (?2 = 12.000, df = 1, p < 0.05); waveform latency (?2 = 5.455, df = 1, p < 0.05). Conclusion. Visual laterality, as well as visual and somatosensory cortical responses to stimuli is better in children without the present articulation disorder, which could be used for timely prevention planning.


2020 ◽  
Vol 13 (1) ◽  
pp. 73-87
Author(s):  
Mila Bulić ◽  
Ines Blažević

The research aimed to check for difference in learning motivation between students learning online and students participating in modern classroom instruction. The study participants included students attending grades 5 to 8, divided into experimental (online classes) and control groups based on pre-testing. The results show that there is no statistically significant difference in motivation between the tested sub-samples. Student motivation for learning natural sciences declines with their years of schooling, but this is not statistically significant. It can be concluded that online teaching of Science and Biology as a learning tool can be as motivating as modern teaching using active classroom methods.


Author(s):  
Noorchaya Yahya ◽  
Hind Alotaibi ◽  
Dina Abdel Salam El-Dakhs

This study reveals the impact of using parallel corpora on EFL students' writing, and how students perceive it. Female undergraduates (n=46) in an EFL writing course in Saudi Arabia were divided randomly into experimental and control groups taught by the same instructor, using the same materials. Students in the experimental group were introduced to three parallel corpora and encouraged to use them in their writing. Tests at the beginning of the semester showed no difference in English proficiency or writing ability between groups. Over the semester, students in both groups also wrote 5 writing assignments and took three writing exams. To examine students' perceptions of parallel corpora, students in the experimental group were asked to write a self-evaluation report and answer an evaluation questionnaire. Quantitative and qualitative analysis showed significant improvement in their writing but no significant difference between groups. However, students' perception of parallel corpora was generally positive.


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