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The rice stem borer (RSB) Chilo suppressalis is a devastating rice pest with resistance to a number of insecticides. Recently, the new meta-diamide insecticide cyproflanilide has been considered an effective insecticide to control RSB. However, its resistance risk has not been reported. In the present study, we aimed to assess the resistance risk and evaluate the fitness cost after the RSB was exposed to cyproflanilide. After five generations of selection, the resistance level of RSB increased by 1.5-fold. When h2 was 0.125, a 10-fold resistance increase in the LD50 values was expected in fourteen and thirty-one generations at the selection intensity of 90% and 50%, respectively. The selected population (RSB-SEL) had significant differences in the developmental duration of eggs, 1st, 2nd, 3rd, and 6th instar larvae, and female pupae compared to the unselected population (RSB-UNSEL). Besides, the adult longevity was shortened, and the average pupal weight of males, the emergence rate, the sex ratio, the oviposition, the mean fecundity, and the full life cycle rate were decreased in RSB-SEL. The intrinsic rate of increase (r), the net reproductive rate (R0), and the finite rate of increase (λ) of RSB-SEL were significantly lower than those of RSB-UNSEL, while the mean generation time (T) of RSB-SEL was significantly longer than that of RSB-UNSEL. Based on the results of the prediction of the generations required for a 10-fold resistance increase in the LD50, a potential risk of resistance development exists in RSB after continuous and excessive use of cyproflanilide. These results will be useful in designing the dose of cyproflanilide to control C. suppressalis in field. [ABSTRACT FROM AUTHOR]

Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) is a major economic pest attacking a variety of crops in Egypt and other Mediterranean countries. S. littoralis has developed resistance to both traditional and novel insecticides. The current study investigated S. littoralis resistance to indoxacarb regarding inheritance mode, realized heritability (h 2), and fitness costs. An indoxacarb-resistant strain (Indoxa-SEL) was obtained by selecting a field strain with indoxacarb. Indoxa-SEL strain outperformed the susceptible one (Indoxa-S) by 29.77-fold after 16 consecutive generations of selection. Based on the LC50 values of the progenies of reciprocal crosses F1 (R♂ × S♀) and F1ʹ (R♀ × S♂), S. littoralis resistance to indoxacarb was found to be autosomal and partially recessive. Chi-square tests for goodness-of-fit between observed and expected mortalities of self-bred F1 and resistant strain reciprocal crosses revealed that the resistance was controlled by multiple genes. The resistant strain had a relative fitness of 0.80, with significantly increased total preovipositional period of females, egg, larvae, pupae, preadult, adult, and total longevity period. The estimated realized heritability value in the Indoxa-SEL strain was 0.21. The current study will contribute to sustaining indoxacarb efficacy and designing effective resistance management programs against S. littoralis. [ABSTRACT FROM AUTHOR]

Studies have shown that COVID-19 patients experience high levels of anxiety, depression, and stress during the pandemic. Patients adopt different coping strategies to reduce their psychological distress To compare the immediate and long-term psychological impact of COVID-19 disease on patients with and without chronic medical illnesses (CMI) and identify coping styles of both groups during the peak of COVID-19 disease in Egypt. This is a cohort follow-up study, that included an online survey consisting of General Health Questionnaire-12, Taylor Manifest Anxiety Scale, Beck Depression Inventory and Brief-COPE scale. The Post-Traumatic Stress Disorder (PTSD) Checklist was completed after 6 months. Questionnaires were distributed to adult patients with a confirmed diagnosis of SARS-CoV-2 virus infection during their quarantine in Egypt. There was no significant difference between the two groups regarding anxiety and depression during the acute infection. Patients without CMI relied significantly on the use of informational support to cope with COVID-19 disease. Patients with CMI continued to show significant depressive symptoms after 6 months without significant PTSD symptoms. COVID-19 has similar immediate psychological impact on patients with and without CMI. However, patients with CMI continue to show depression on long-term follow-up. [ABSTRACT FROM AUTHOR]

The cowpea aphid (Aphis craccivora Koch) is considered a serious insect pest attacking several crops. We carried out biochemical studies to elucidate the role of the metabolising enzymes in conferring resistance to thiamethoxam, in two strains (resistant and susceptible) of the cowpea aphid. Bioassay experiments showed that the thiamethoxam selected strain developed a 48 fold resistance after consecutive selection with thiamethoxam for 12 generations. This resistant strain also exhibited cross-resistance to the tested carbamates; pirimicarb and carbosulfan, organophosphorus (malathion, fenitrothion, and chlorpyrifos-methyl), and the neonicotinoid (acetamiprid). Synergism studies have indicated that S,S,S-tributyl phosphorotrithioate (DEF), a known inhibitor for esterases, increased thiamethoxam toxicity 5.58 times in the resistant strain compared with the susceptible strain. Moreover, the biochemical determination revealed that carboxylestersae activity was 30 times greater in the resistant strain than in the susceptible strain. In addition, the enzyme activity of glutathione S-transferase (GST) and mixed function oxidases (mfo) increased only in the resistant strain 3.7 and 2.7 times, respectively, in relation to the susceptible (the control). Generally, our results suggest that the higher activity of the detoxifying enzymes, particularly carboxylesterase, in the resistant strain of the cowpea aphid, apparently have a significant role in endowing resistance to thiamethoxam, although additional mechanisms may contribute.

Background The Coronavirus Disease 2019 (COVID-19) pandemic was an ongoing global stress encountered by individuals with preexisting chronic illnesses. This study aimed to evaluate the perceived fears of contracting COVID-19 virus (FCV) infection and to address the associated correlates among patients with multiple sclerosis (MS) during the pandemic. Patients and Methods A cross-sectional study included a total of 120 Egyptian patients with MS who were followed up at the Zagazig University Neurology Outpatient Clinics during the COVID-19 outbreak between May 1 and October 31, 2020. The participants, consecutively selected by the convenience sampling method, were interviewed using the Fear of COVID-19 Scale (FCV-19S), Hospital Anxiety and Depression Scale, Expanded Disability Status Scale, and Five-item Modified Fatigue Impact Scale for the assessment of FCV, comorbid anxiety, and depressive symptoms, associated fatigability, and levels of disability, respectively. Results Around 58% of patients with MS (n= 69) experienced intensified FCV. Those who were unmarried, reporting higher levels of anxiety and depression, diagnosed with primary or secondary progressive MS subtypes, with a longer course of illness, and associated fatigability and disability, were more likely to experience FCV. Comorbid anxiety symptoms were positively correlated with illness duration (r= 0.19, P= 0.039), increased fatigue (r= 0.47, P <0.001), and disability (r= 0.36, P <0.001), while depressive symptoms were positively correlated with increased fatigue (r= 0.37, P <0.001) and disability (r= 0.30, P <0.001). Conclusions FCV was prevalent among patients with MS. Being unmarried, heightened anxiety, longer duration of illness, and associated fatigability would predict FCV. Both psychological and physical assessment measures of patients with MS should be regularly implemented. [ABSTRACT FROM AUTHOR]

Byline: Rabie. Soliman, Eman. Fouad Background and Aim: Transnasal transsphenoidal resection of pituitary tumours is associated with blood loss and wide fluctuations in haemodynamic parameters. The aim of the present [...]

Opioid use disorders related to tramadol (OUD-T) were under-reported in Egypt. The objective was to estimate the prevalence and associated correlates of OUD-T among male psychiatric patients. A total of 168 male inpatients and outpatients with Axis-I psychiatric disorders was randomly selected from Zagazig University Hospitals, Egypt. The patients were interviewed using Structured Clinical Interview for DSM-5 disorders (SCID-I), Drug Use Disorders Identification Test (DUDIT), and urine screening for drugs. The prevalence of OUD-T was 48.8%, with the highest prevalence in patients with depressive disorders (58.5%). Old age (OR 1.2, 95% CI: 1.1, 1.2), and cannabis use (OR 46.9, 95% CI: 10.8, 118.7) predicted OUD-T. About 45% of patients with OUD-T used tramadol alone whereas the rest used at least one drug plus tramadol. Tramadol-related problems and dependence were positively correlated with the tramadol daily dose, smoking, alcohol and heroin use, and inversely with the psychiatric disorder remission and age of smoking onset and substance use disorders (SUDs). OUD-T were common among male psychiatric patients, with a considerable relationship between OUD-T and use of other substances (cannabis). Further longitudinal studies need to investigate the relationship between OUD-T and other SUDs, and psychiatric disorders. [ABSTRACT FROM AUTHOR]