58 research outputs found

    Effects of two host plants on the functional response of adult Orius albidipennis (Hem.: Anthocoridae) to different densities of the second instar larvae of Thrips tabaci (Thys.: Thripidae)

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    Thrips tabaci Lindeman, is one of the most important pests of vegetables and ornamental plants across the world. The functional response of Orius albidipennis Reuter was studied in relation to different densities of second instar larvae of T. tabaci. Laboratory experiments were conducted to evaluate the effect of two different host plants (cucumber and bean plantlets) on the functional response and its parameters (attack rate and handling time) using different densities of 2, 5, 10, 20, 30 and 40 thrips. The cucumber and bean plantlets, in relatively small pots with a diameter of 4 cm and 7 cm high were supplied to the predators to feed on the thrips in a 24-hour-period. Each density was repeated 10 times. The experiment was carried out at 25-29°C, 60 ± 5% R.H. and photoperiod of 16: 8 L: D hours. The logistic regression suggested a type II functional response on two host plants. The Rogerâs random predator equation was compatible with the results. The type of functional response was not affected by the host plants. Attack rate (a), handling time (Th) and maximum predation of O. albidipennis were 0.073 ± 0.013, 1.67 ± 0.12 and 14.37 on the cucumber and 0.095 ± 0.02, 1.51 ± 0.11 and 15.89 on the bean plantlets, respectively. There was no significant difference among estimated parameters in both plantlets

    Finding the undiscovered roles of genes: an approach using mutual ranking of coexpressed genes and promoter architecture-case study: dual roles of thaumatin like proteins in biotic and abiotic stresses

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    Regarding the possible multiple functions of a specific gene, finding the alternative roles of genes is a major challenge. Huge amount of available expression data and the central role of the promoter and its regulatory elements provide unique opportunely to address this issue. The question is that how the expression data and promoter analysis can be applied to uncover the different functions of a gene. A computational approach has been presented here by analysis of promoter regulatory elements, coexpressed gene as well as protein domain and prosite analysis. We applied our approach on Thaumatin like protein (TLP) as example. TLP is of group 5 of pathogenesis related proteins which their antifungal role has been proved previously. In contrast, Osmotin like proteins (OLPs) are basic form of TLPs with proved role only in abiotic stresses. We demonstrated the possible outstanding homolouges involving in both biotic and abiotic stresses by analyzing 300 coexpressed genes for each Arabidopsis TLP and OLP in biotic, abiotic, hormone, and light microarray experiments based on mutual ranking. In addition, promoter analysis was employed to detect transcription factor binding sites (TFBs) and their differences between OLPs and TLPs. A specific combination of five TFBs was found in all TLPs presenting the key structure in functional response of TLP to fungal stress. Interestingly, we found the fungal response TFBs in some of salt responsive OLPs, indicating the possible role of OLPs in biotic stresses. Thirteen TFBS were unique for all OLPs and some found in TLPs, proposing the possible role of these TLPs in abiotic stresses. Multivariate analysis showed the possibility of estimating models for distinguishing biotic and abiotic functions of TIPs based on promoter regulatory elements. This is the first report in identifying multiple roles of TLPs and OLPs in biotic and abiotic stresses. This study provides valuable clues for screening and discovering new genes with possible roles in tolerance against both biotic and abiotic stresses. Interestingly, principle component analysis showed that promoter regulatory elements of TLPs and OLPs are more variable than protein properties reinforcing the prominent role of promoter architecture in determining gene function alteration.Tahereh Deihimi, Ali Niazi, Mansour Ebrahimi, Kimia Kajbaf, Somaye Fanaee, Mohammad R. Bakhtiarizadeh and Esmaeile Ebrahimi

    Investigating the association between obesity and asthma in 6- to 8-year-old Saudi children:a matched case-control study

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    Background: Previous studies have demonstrated an association between obesity and asthma, but there remains considerable uncertainty about whether this reflects an underlying causal relationship. Aims: To investigate the association between obesity and asthma in pre-pubertal children and to investigate the roles of airway obstruction and atopy as possible causal mechanisms. Methods: We conducted an age- and sex-matched case–control study of 1,264 6- to 8-year-old schoolchildren with and without asthma recruited from 37 randomly selected schools in Madinah, Saudi Arabia. The body mass index (BMI), waist circumference and skin fold thickness of the 632 children with asthma were compared with those of the 632 control children without asthma. Associations between obesity and asthma, adjusted for other potential risk factors, were assessed separately in boys and girls using conditional logistic regression analysis. The possible mediating roles of atopy and airway obstruction were studied by investigating the impact of incorporating data on sensitisation to common aeroallergens and measurements of lung function. Results: BMI was associated with asthma in boys (odds ratio (OR)=1.14, 95% confidence interval (CI), 1.08–1.20; adjusted OR=1.11, 95% CI, 1.03–1.19) and girls (OR=1.37, 95% CI, 1.26–1.50; adjusted OR=1.38, 95% CI, 1.23–1.56). Adjusting for forced expiratory volume in 1 s had a negligible impact on these associations, but these were attenuated following adjustment for allergic sensitisation, particularly in girls (girls: OR=1.25; 95% CI, 0.96–1.60; boys: OR=1.09, 95% CI, 0.99–1.19). Conclusions: BMI is associated with asthma in pre-pubertal Saudi boys and girls; this effect does not appear to be mediated through respiratory obstruction, but in girls this may at least partially be mediated through increased risk of allergic sensitisation

    Risk of acute kidney injury and survival in patients treated with Metformin:an observational cohort study

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    Background: Whether metformin precipitates lactic acidosis in patients with chronic kidney disease (CKD) remains under debate. We examined whether metformin use was associated with an increased risk of acute kidney injury (AKI) as a proxy for lactic acidosis and whether survival among those with AKI varied by metformin exposure. Methods: All individuals with type 2 diabetes and available prescribing data between 2004 and 2013 in Tayside, Scotland were included. The electronic health record for diabetes which includes issued prescriptions was linked to laboratory biochemistry, hospital admission, death register and Scottish Renal Registry data. AKI events were defined using the Kidney Disease Improving Global Outcomes criteria with a rise in serum creatinine of at least 26.5 μmol/l or a rise of greater than 150% from baseline for all hospital admissions. Cox Regression Analyses were used to examine whether person-time periods in which current metformin exposure occurred were associated with an increased rate of first AKI compared to unexposed periods. Cox regression was also used to compare 28 day survival rates following first AKI events in those exposed to metformin versus those not exposed. Results: Twenty-five thousand one-hundred fourty-eight patients were included with a total person-time of 126,904 person years. 4944 (19.7%) people had at least one episode of AKI during the study period. There were 32.4 cases of first AKI/1000pyrs in current metformin exposed person-time periods compared to 44.9 cases/1000pyrs in unexposed periods. After adjustment for age, sex, diabetes duration, calendar time, number of diabetes drugs and baseline renal function, current metformin use was not associated with AKI incidence, HR 0.94 (95% CI 0.87, 1.02, p = 0.15). Among those with incident AKI, being on metformin at admission was associated with a higher rate of survival at 28 days (HR 0.81, 95% CI 0.69, 0.94, p = 0.006) even after adjustment for age, sex, pre-admission eGFR, HbA1c and diabetes duration. Conclusions: Contrary to common perceptions, we found no evidence that metformin increases incidence of AKI and was associated with higher 28 day survival following incident AKI

    The cytochrome P450 CYP6P4 is responsible for the high pyrethroid resistance in knockdown resistance-free Anopheles arabiensis.

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    Pyrethroid insecticides are the front line vector control tools used in bed nets to reduce malaria transmission and its burden. However, resistance in major vectors such as Anopheles arabiensis is posing a serious challenge to the success of malaria control. Herein, we elucidated the molecular and biochemical basis of pyrethroid resistance in a knockdown resistance-free Anopheles arabiensis population from Chad, Central Africa. Using heterologous expression of P450s in Escherichia coli coupled with metabolism assays we established that the over-expressed P450 CYP6P4, located in the major pyrethroid resistance (rp1) quantitative trait locus (QTL), is responsible for resistance to Type I and Type II pyrethroid insecticides, with the exception of deltamethrin, in correlation with field resistance profile. However, CYP6P4 exhibited no metabolic activity towards non-pyrethroid insecticides, including DDT, bendiocarb, propoxur and malathion. Combining fluorescent probes inhibition assays with molecular docking simulation, we established that CYP6P4 can bind deltamethrin but cannot metabolise it. This is possibly due to steric hindrance because of the large vdW radius of bromine atoms of the dihalovinyl group of deltamethrin which docks into the heme catalytic centre. The establishment of CYP6P4 as a partial pyrethroid resistance gene explained the observed field resistance to permethrin, and its inability to metabolise deltamethrin probably explained the high mortality from deltamethrin exposure in the field populations of this Sudano-Sahelian An. arabiensis. These findings describe the heterogeneity in resistance towards insecticides, even from the same class, highlighting the need to thoroughly understand the molecular basis of resistance before implementing resistance management/control tools

    Usporedba djelovanja blokatora kalcijevih kanala, blokatora autonomnoga živčanog sustava te inhibitora slobodnih radikala na hiposekreciju inzulin iz izolirnih langerhansovih otočića štakora uzrokovanu diazinonom

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    Hyperglycaemia has been observed with exposure to organophosphate insecticides. This study was designed to compare the effects of calcium channel blockers, alpha-adrenergic, beta-adrenergic, and muscarinic receptor blockers, and of free radical scavengers on insulin secretion from diazinon-treated islets of Langerhans isolated from the pancreas of rats using standard collagenase digestion, separation by centrifugation, and hand-picking technique. The islets were then cultured in an incubator at 37 °C and 5 % CO2. In each experimental set 1 mL of 8 mmol L-1 glucose plus 125 µg mL-1 or 625 µg mL-1 of diazinon were added, except for the control group, which received 8 mmol L-1 glucose alone. The cultures were then treated with one of the following: 30 µmol L-1 atropine, 100 µmol L-1 ACh + 10 µmol L-1 neostigmine, 0.1 µmol L-1 propranolol, 2 µmol L-1 nifedipine, 50 µmol L-1 phenoxybenzamine, or 10 µmol L-1 alphatocopherol. In all experiments, diazinon significantly reduced glucose-stimulated insulin secretion at both doses, showing no dose dependency, as the average inhibition for the lower dose was 62.20 % and for the higher dose 64.38 %. Acetylcholine and alpha-tocopherol restored, whereas atropine potentiated diazinoninduced hyposecretion of insulin. Alpha-, beta- and calcium channel blockers did not change diazinoninduced effects. These findings suggest that diazinon affects insulin secretion mainly by disturbing the balance between free radicals and antioxidants in the islets of Langerhans and by inducing toxic stress.U osoba izloženih organofosfatnim insekticidima zamijećen je nastanak hiperglikemije. Svrha je ovo istraživanja bila usporediti djelovanje blokatora kalcijevih kanala, alfa i beta-adrenergičkih i muskarinskih receptora te inhibicije slobodnih radikala na lučenje inzulina iz Langerhansovih otočića izoliranih iz štakora tretiranih diazinonom. Otočići su izolirani iz gušterače štakora s pomoću standardnog postupka digestije kolagenazom, odvajanja centrifugiranjem i metodom ručnog probira (engl. hand-picking) te su kultivirani u inkubatoru pri 37 °C i 5 % CO2. Pokusne su kulture inkubirane s 1 mL glukoze u koncentraciji od 8 mmol L-1 te diazinonom u dozi od 125 μg mL-1, odnosno 625 μg mL-1. U kontrolu je dodana samo glukoza u koncentraciji od 8 mmol L-1. Nakon toga je u kulture dodan jedan od sljedećih agenasa: 30 µmol L-1 atropin, 100 µmol L-1 ACh + 10 µmol L-1 neostigmin, 0,1 µmol L-1 propranolol, 2 µmol L-1 nifedipin, 50 µmol L-1 fenoksibenzamin, odnosno 10 µmol L-1 alfa-tokoferol. U svim je pokusima diazinon značajno smanjio lučenje inzulina, s time da je doza od 125 μg mL-1 dovela do 62,2 %-tne inhibicije, a doza od 625 μg mL-1 do 64,38 %-tne inhibicije lučenja inzulina, što upućuje na djelovanje neovisno o dozi. Acetilkolin i alfa-tokoferol su ponovno potaknuli lučenje inzulina, za razliku od atropina koji ga je dodatno smanjio. Primjena blokatora alfa i beta-adrenergičkih receptora te blokatora kalcijevih kanala nije utjecala na djelovanje diazinona. Autori zaključuju da diazinon utječe na lučenje inzulina ponajviše narušavanjem ravnoteže između slobodnih radikala i antioksidansa u Langerhansovim otočićima te dovodi do toksičnoga stresa

    Normalized Electromyography of Shoulder Muscles during Selected Functional Tasks of Upper Limb in Patients with Shoulder Impingement Syndrome

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    Abstract: Background & Aims: Precise muscle activity pattern is required to maintain normal shoulder function and any alteration in muscle activity can result in movement impairment. The purpose of this study was to assess normalized electromyography (EMG) of shoulder muscles during selected functional tasks of upper limb in patients with shoulder impingement syndrome. Methods: Test group consisted of 15 subjects with shoulder impingement syndrome selected by nonprobability convenient sampling and control group consisted of 15 matched healthy subjects. In each group selected exercises including open kinetic chain with and without external load and closed kinetic chain with axial load were done and during each exercise surface EMG from selected muscle was recorded. Results: There was significant difference between the two groups in the activities of upper trapezius, infraspinatus and three regions of deltoid muscle (P2E showed minimum changes and tripod showed maximum changes in muscle activity domain. Conclusion: Decrease in activity domain of infraspinatus and trapezius muscles in patients with shoulder impingement syndrome causes impairment of shoulder function. D2E with causing minimum changes and Tripod with causing maximum changes in muscles activity domain are suggested respectively as the first and the last activity patterns in the treatment of these patients. Keywords: Shoulder joint, Shoulder impingement syndrome, Electromyography, Exercise, Biomechanic

    The Effectiveness of Quality of Life Therapy on Anxiety and Depression in Female High School students

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    The purpose of the present study was to determine the effectiveness of Quality Of Life Therapy (QOLT) on anxiety and stress of female high-school students in Dehaghan. The study was a semi-experimental study with experimental-control groups and a follow-up (45 days). From among 150 respondents who answered the items of anxiety and depression questionnaires, 48 respondents who received the highest scores were selected and assigned into two groups (each group included 24 subjects). Then these subjects in each group were divided into two 12 subjects experimental and control groups and 8 sessions of quality of life therapy interventions was administered to experimental groups. The results of analysis of covariance showed that quality of life therapy had significantly decreased the degree of anxiety and depression in experimental groups as compared to the control groups in posttest and follow-up stage. (p<0.0005)

    The nature of Iraqi Turkmens and their relationship with Seljuq Turkmen (1009-1043)

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    Migration of Seljuq Turks and formation of the first government with a tribal origin was the preface of outstanding changes in the culture of Iran. Iraqi Turkmens as pioneers of this migration because of penetration in non-Arab regions of Iraq were known as Iraqis. The nature and ethnic roots of this groups and their relationship with Seljuqs can be investigated from two different perspectives: A group of historians know them as Israel citizens who were authorized by the son of Seljuq and migrated to Iran after he was captured by Mohammad Ghaznavid. The present article referring to available sources does not approve this theory and considers them as a branch of Seljuqs. From another perspective, actions Ghaznavids performed to restrain them and the policy Seljuqs later applied for Turkmens, not only before their arrival to Iran but also after their seizing power in Iran, experienced meaningful ups and downs. Such actions can be divided into three steps: neutral state against them, temporary alliance with them and repressive state against them
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