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Faisal Alsaif,1 Lina Neel,2 Saleh Almuaiqel,1 Abdulaziz Almuhanna,1 Jude Feda,3 Nouf Alrumaihi,4 Omar Alanazi,3 Mohammed Almansour,3 Majda Fuad Saeed,3 Mona Soliman3 1College of Medicine, King Saud University, Riyadh, Saudi Arabia; 2College of Medicine, Alfaisal University, Riyadh, Saudi Arabia; 3Medical Education Department, College of Medicine, King Saud University, Riyadh, Saudi Arabia; 4Saudi Commission of Health Specialties, College of Medicine, King Saud University, Riyadh, Saudi ArabiaCorrespondence: Mona Soliman, Head of Medical Education Department, Professor of Medical Education and Physiology, College of Medicine, King Saud University, Riyadh, Saudi Arabia, Tel +966505468581, Email msoliman1@ksu.edu.saBackground: COVID-19 pandemic has resulted in a sudden shift to online education. PBL was one of the components that was transformed to online. The aim of the present study was to investigate the impact of the sudden shift to virtual PBL during COVID-19 pandemic in achieving the intended learning objectives of the PBL and to explore the students’ perception of the virtual versus traditional PBL.Methods: This is a retrospective study that was conducted in the college of medicine, King Saud University. We compared the perception of third year students who participated in traditional face-to-face PBL in 2019– 2020 and in the virtual PBL in 2020– 2021. We compared the performance of the students in the traditional face-to-face and in virtual PBL. An online survey was distributed from October to December 2021. The survey contained 7 sections. Each section included several questions comparing virtual and traditional PBL in that aspect.Results: Out of 284 third year medical students, 124 students responded with a response rate of 43.66%. More than half of the students (n = 77, 63%) felt significantly motivated to actively participate in PBL sessions in a virtual learning environment, motivated to learn and support group work and gained critical thinking skills (mean = 3.54 ± 0.12 versus 3.59 ± 0.14, p < 0.001). The majority of students (n = 82, 66%) felt significantly more satisfied about their learning during the virtual PBL versus traditional PBL (mean = 3.48 ± 0.42 versus 3.91 ± 0.59, p < 0.001). There was no significant difference in the students’ performance in traditional versus virtual PBL (mean = 4.77 ± 0.22 versus 4.79 ± 0.29, p = 0.2).Conclusion: The results of this study showed that students were significantly more satisfied with the experience in the virtual versus traditional PBL. Medical students’ performances in virtual PBL were comparable to the traditional face-to-face approach.Keywords: COVID-19, problem-based learning, PBL, traditional, virtual, learning, medical students

The risk assessment of trace elements has received substantial attention for the achievement of UN Sustainable Developmental Goals (UN-SDGs). The present study aimed to evaluate health and ecological risks associated with trace element accumulation in Brassica oleracea under wastewater irrigations from three different areas. This study, for the first time, compared the pros and cons of mixed water crop irrigation (wastewater with fresh/groundwater). A pot experiment was conducted to evaluate the buildup of eight trace elements (As, Cu, Cd, Mn, Fe, Pb, Ni and Zn) in soil and B. oleracea plants irrigated with wastewater alone and mixed with fresh/groundwater. Specific ecological [degree of contamination (C d ), potential ecological risk index (PERI), pollution load index (PLI), geo-accumulation index (I geo )], phytoaccumulation [bioconcentration factor (BCF) and transfer factor (TF)] and health risk models [chronic daily intake (CDI), hazard quotient (HQ), cancer risk (CR)] were applied to assess the overall contamination of trace elements in the soil-plant-human system. Moreover, these indices were compared with the literature data. The concentration of Cd, Fe and Mn exceeded the threshold limits of 10, 500 and 200 mg kg -1 , respectively, for agricultural soil. Overall, all the irrigation waters caused significant pollution load in soil indicating high ecological risk (C d  > 24, PERI > 380, Igeo > 5, PLI > 2). Not all the mixing treatments caused a reduction in trace element buildup in soil. The mixing of wastewater-1 with either groundwater or freshwater increased trace element levels in the soil as well as risk indices compared to wastewater alone. The BCF and TF values were > 1, respectively, for 66% and 7% treatments. Trace element concentration in plants and associated health risk were minimized in mixed wastewater treatments. There were 22% and 32% reduction in HQ and CR when wastewater was mixed with freshwater and 29% and 8% when mixed with groundwater. Despite total reduction, a great variation in % change in risk indices was observed with respect to the area of wastewater collection. Therefore, mixed water irrigation may be a good management strategy, but its recommendation depends on soil properties and composition of waters used for mixing. Moreover, it is recommended that the freshwater and wastewater of the particular area may be continuously monitored to avoid potential associated health hazards., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Conductive agro-industrial wastes as accelerants in the anaerobic digestion (AD) of organic waste is a good technique for developing a rural circular economy, such as producing bioenergy and biofertilizer. This study disclosed the a role of sugar cane bagasse ash (SCBA) in enhancing the bioenergy (biogas) yield and digestate fertility via anaerobic co-digestion (AcoD) of buffalo dung (BD) and vegetable residue (VR) under mesophilic conditions (37 ᴼC). Firstly, an optimal BD/VR ratio (1:3) was determined based on biogas yield by introducing five different BD/VR ratios (1:0, 3:1, 1:1, 1:3, and 0:1) into AcoD systems. Secondly, the biogas yield was increased further by adding SCBA at five different concentrations (0, 0.5, 1, 1.5, and 2 wt%). Experimental results disclosed that the 1.5 wt% of SCBA gave the highest cumulative biogas yield (153.67 mL/g VS), COD removal rate (31.18%), and fertility (5.08%). Moreover, a framework is suggested to understand the role of SCBA in the enhanced DIET mechanism. This work documents an environmentally friendly and economical technique for developing a rural circular bioeconomy via the AD of organic agro-waste., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Soil heavy metal contamination and salinity constitute a major environmental problem worldwide. The affected area and impact of these problems are increasing day by day; therefore, it is imperative to restore their potential using environmentally friendly technology. Plant growth-promoting rhizobacteria (PGPR) provides a better option in this context. Thirty-seven bacteria were isolated from the rhizosphere of maize cultivated in metal- and salt-affected soils. Some selected bacterial strains grew well under a wide range of pH (4-10), salt (5-50 g/L), and Cd (50-1000 mg/L) stress. Three bacterial strains, Exiguobacterium aestuarii (UM1), Bacillus cereus (UM8), and Bacillus megaterium (UM35), were selected because of their robust growth and high tolerance to both stress conditions. The bacterial strains UM1, UM8, and UM35 showed P-solubilization, whereas UM8 and UM35 exhibited 1-aminocyclopropane-1-carboxylate deaminase activity and indole acetic acid (IAA) production, respectively. The bacterial strains were inoculated on Brassica juncea plants cultivated in Cd and salt-affected soils due to the above PGP activities and stress tolerance. Plants inoculated with the bacterial strains B. cereus and B. megaterium significantly (p < 0.05) increased shoot fresh weight (17 ± 1.17-29 ± 0.88 g/plant), shoot dry weight (2.50 ± 0.03-4.40 ± 0.32 g/plant), root fresh weight (7.30 ± 0.58-13.30 ± 0.58 g/plant), root dry weight (0.80 ± 0.04-2.00 ± 0.01 g/plant), and shoot K contents (62.76 ± 1.80-105.40 ± 1.15 mg/kg dwt) in normal and stressful conditions. The bacterial strain B. megaterium significantly (p < 0.05) decreased shoot Na + and Cd ++ uptake in single and dual stress conditions. Both bacterial strains, E. aestuarii and B. cereus, efficiently reduced Cd ++ translocation and bioaccumulation in the shoot. Bacterial inoculation improved the uptake of K + and Ca ++ , while restricted Na + and Cd ++ in B. juncea shoots indicated their potential to mitigate the dual stresses of salt and Cd in B. juncea through ion homeostasis., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Iftikhar Ahmad reports was provided by COMSATS University, Islamabad, Vehari Campus., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Using plant extracts as eco-friendly reducing and stabilizing agents for the synthesis of nanoparticles has gained significant attention in recent years. The current study explores the green synthesis of silver nanoparticles (AgNPs) using the Avena fatua extract and evaluates their antifungal activity against Fusarium oxysporum f.sp. lycopersici ( Fol ), a fungal plant pathogen. A green and sustainable approach was adopted to synthesize silver nanoparticles before these nanoparticles were employed for anti-fungal activity. The primary indication that AgNPs had formed was performed using UV-vis spectroscopy, where a strong peak at 425 nm indicated the effective formation of these nanoparticles. The indication of important functional groups acting as reducing and stabilizing agents was conducted using the FTIR study. Additionally, morphological studies were executed via SEM and AFM, which assisted with more effectively analyzing AgNPs. Crystalline behavior and size were estimated using powder XRD, and it was found that AgNPs were highly crystalline, and their size ranged from 5 to 25 nm. Synthesized AgNPs exhibited significant antifungal activity against Fol at a concentration of 40 ppm. Furthermore, the inhibitory index confirmed a positive correlation between increasing AgNPs concentration and exposure duration. This study suggests that the combined phytochemical mycotoxic effect of the plant extract and the smaller size of synthesized AgNPs were responsible for the highest penetrating power to inhibit Fol growth. Moreover, this study highlights the potential of using plant extracts as reducing and capping agents for the green synthesis of AgNPs with antifungal properties. The study concludes that A. fatua extract can synthesize antifungal AgNPs as a sustainable approach with robust antifungal efficacy against Fol , underscoring their promising potential for integration into plant protection strategies.

Chickpea ( Cicer arietinum L.) is a major pulse crop worldwide, renowned for its nutritional richness and adaptability. Weeds are the main biotic factor deteriorating chickpea yield and nutritional quality, especially Asphodelus tenuifolius Cav. The present study concerns a two-year (2018-19 and 2019-20) field trial aiming at evaluating the effect of weed management on chickpea grain quality. Several weed management practices have been here implemented under a factorial randomized complete block design, including the application of four herbicides [bromoxynil (C 7 H 3 Br 2 NO) + MCPA (Methyl-chlorophenoxyacetic acid) (C 9 H 9 ClO 3 ), fluroxypyr + MCPA, fenoxaprop- p -ethyl (C 18 H 16 ClNO 5 ), pendimethalin (C 13 H 19 N 3 O 4 )], the extracts from two allelopathic weeds ( Sorghum halepense and Cyperus rotundus ), two mulches (wheat straw and eucalyptus leaves), a combination of A. tenuifolius extract and pendimethalin, and an untreated check (control). Chickpea grain quality was measured in terms of nitrogen, crude protein, crude fat, ash, and oil content. The herbicides pendimethalin (Stomp 330 EC (emulsifiable concentrate) in pre-emergence at a rate of 2.5 L ha -1 ) and fenoxaprop- p -ethyl (Puma Super 7.5 EW (emulsion in water) in post-emergence at a rate of 1.0 L ha -1 ), thanks to A. tenuifolius control, showed outstanding performance, providing the highest dietary quality of chickpea grain. The herbicides Stomp 330 EC, Buctril Super 40 EC, Starane-M 50 EC, and Puma Super 7.5 EW provided the highest levels of nitrogen. Outstanding increases in crude protein content were observed with all management strategies, particularly with Stomp 330 EC and Puma Super 7.5 EW (+18% on average). Ash content was highly elevated by Stomp 330 EC and Puma Super 7.5 EW, along with wheat straw mulching, reaching levels of 2.96% and 2.94%. Crude fat content experienced consistent elevations across all treatments, with the highest improvements achieved by Stomp 330 EC, Puma Super 7.5 EW, and wheat straw mulching applications. While 2018-19 displayed no significant oil content variations, 2019-20 revealed the highest oil content (5.97% and 5.96%) with herbicides Stomp 330 EC and Puma Super 7.5 EW, respectively, followed by eucalyptus leaves mulching (5.82%). The results here obtained are of key importance in the agricultural and food sector for the sustainable enhancement of chickpea grain's nutritional quality without impacting the environment.

Introduction: A stoma is an artificial anastomosis of the gastrointestinal tract to the abdominal skin wall to reroute the stream of feces. Fecal diversion, bowel decompression, and anastomosis protection are common indications for stomas. Relative to other surgical operations, stomas have a high morbidity rate, with rates averaging 40% and ranging 14-79%. The most common early complication was peristomal skin irritation. In contrast, parastomal hernias were the most common late complication., Methods: This research was performed at King Hamad University Hospital (KHUH) in the Kingdom of Bahrain. Our study included patients who had undergone ileostomies and colostomies. The inclusion criteria included adult patients who are 15 years and older, both emergency and elective cases, and with ASA score of 1-4. The excluded patients were those who had had their stomas performed outside of KHUH and those who were not following up in the hyperbaric department of our hospital. This study was performed using a retrospective study design. The sample size was 98 which included patients with stomas that were following up with the hyperbaric team between January 2018 and February 2021., Results: We have broken down the indications for stoma formation. The breakdown of all our documented complications are illustrated in the given figure., Conclusion: Within our institutional study, 63.3% of stoma complications consisted of skin problems. This formed the majority of complications. Establishing a stoma care unit would offer continuous support and care to patients and help them in returning to an optimal quality of life. Additionally, this goal can be met through preoperative and postoperative education regarding surgery and stoma formation. This includes preoperative stoma marking and siting, as well as improved recovery through instruction from knowledgeable stoma care specialists regarding hands-on stoma care.Finally, patients can be assisted through specialized stoma clinics., How to Cite This Article: Qassim T, Saeed MF, Qassim A, et al . Intestinal Stomas-Current Practice and Challenges: An Institutional Review. Euroasian J Hepato-Gastroenterol 2023;13(2):115-119., Competing Interests: Source of support: Nil Conflict of interest: None, (Copyright © 2023; The Author(s).)

Introduction: Low soil fertility and high fertilizer costs are constraints to wheat production, which may be resolved with integrating fertilizer phosphorus (P) and farm-yard manure (FYM). Study objectives were to evaluate P source impacts on soil, P efficiency, and wheat growth in a calcareous soil., Methods: Treatments included P fertilizer (0, 17, 26, or 39 kg P ha-1) and/or FYM (0 or 10 T ha-1) in a: 1) incubation experiment and 2) wheat (Triticum aestivum spp.) field experiment., Results and Discussion: Soil organic matter increased (30-72%) linearly for both fertilizer and FYM, whereas pH decreased (0.1-0.3 units) with fertilizer only. Addition of fertilizer and FYM increased plant available P (AB-DTPA extractable soil P) an average of 0.5 mg P kg-1 soil week-1 with incubation. The initial increase was 1-9 mg P kg-1, with further increase after 84 d of ~3-17 mg P kg-1. There was also a significant increase of available P in the soil supporting plants in the field study, although the magnitude of the increase was only 2 mg kg-1 at most for the highest fertilizer rate + FYM. Grain (66 to 119%) and straw (25-65%) yield increased significantly, peaking at 26 kg P ha-1 + FYM. The P Absorption Efficiency (PAE), P Balance (PB), and P Uptake (PU) increased linearly with P rate, with the highest levels at the highest P rate. The P Use Efficiency (PUE) was highest at the lowest rates of P, with general decreases with increasing P, although not consistently. Principal component analysis revealed that 94.34 % of the total variance was accounted for with PC1 (84.04 %) and PC2 (10.33 %), with grain straw yield significantly correlated to SOM, PU, and PAE. Regression analysis showed highly significant correlation of PB with P-input (R2= 0.99), plant available P (R2= 0.85), and PU (R2= 0.80). The combination of FYM at the rate of 10 T ha-1 and fertilizer P at 26 kg P ha-1 was found as the optimum dose that significantly increased yield. It is concluded that FYM concoction with fertilizer-P not only improved SOM and residual soil P, but also enhanced wheat yields with reasonable P efficiency., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Jamal, Saeed, Mihoub, Hopkins, Ahmad and Naeem.)

Pyramiding of major resistance (R) genes through marker-assisted selection (MAS) is a useful way to attain durable and broad-spectrum resistance against Xanthomonas oryzae pv. oryzae pathogen, the causal agent of bacterial blight (BB) disease in rice (Oryza sativa L.). The present study was designed to pyramid four broad spectrum BB-R genes (Xa4, xa5, xa13 and Xa21) in the background of Basmati-385, an indica rice cultivar with much sought-after qualitative and quantitative grain traits. The cultivar, however, is susceptible to BB and was therefore, crossed with IRBB59 which possesses R genes xa5, xa13 and Xa21, to attain broad and durable resistance. A total of 19 F1 plants were obtained, some of which were backcrossed with Basmati-385 and large number of BC1F1 plants were obtained. In BC1F2 generation, 31 phenotypically superior genotypes having morphological features of Basmati-385, were selected and advanced up to BC1F6 population. Sequence-tagged site (STS)-based MAS was carried out and phenotypic selection was made in each successive generation. In BC1F6 population, potentially homozygous recombinant inbred lines (RILs) from each line were selected and evaluated on the bases of STS evaluation and resistance to local Xanthomonas oryzae pv. oryzae (Xoo) isolates. Line 23 was found pyramided with all four BB-R genes i.e., Xa4, xa5, xa13 and Xa21. Five genotypes including line 8, line 16, line 21, line 27 and line 28 were identified as pyramided with three R genes, Xa4, xa5 and xa13. Pathological study showed that rice lines pyramided with quadruplet or triplet R genes showed the highest level of resistance compared to doublet or singlet R genes. Thus, line 23 with quadruplet, and lines 8, 16, 21, 27, and 28 with triplet R genes, are recommended for replicated yield and resistance trials before release as new rice varieties. Further, traditional breeding coupled with MAS, is a solid way to attain highly effective BB-resistant rice lines with no yield cost.

The research was focused on the ability of wheat aphids Sitobion avenae , harboring bacterial secondary symbionts (BSS) Hamiltonella defensa or Regiella insecticola , to withstand exposure to fungal isolates of Beauveria bassiana and Metarhizium brunneum . In comparison to aphids lacking bacterial secondary symbionts, BSS considerably increased the lifespan of wheat aphids exposed to B. bassiana strains (Bb1022, EABb04/01-Tip) and M. brunneum strains (ART 2825 and BIPESCO 5) and also reduced the aphids' mortality. The wheat aphid clones lacking bacterial secondary symbionts were shown to be particularly vulnerable to M. brunneum strain BIPESCO 5. As opposed to wheat aphids carrying bacterial symbionts, fungal pathogens infected the wheat aphids lacking H. defensa and R. insecticola more quickly. When treated with fungal pathogens, bacterial endosymbionts had a favorable effect on the fecundity of their host aphids compared to the aphids lacking these symbionts, but there was no change in fungal sporulation on the deceased aphids. By defending their insect hosts against natural enemies, BSS increase the population of their host society and may have a significant impact on the development of their hosts.

Elevated noise level is an emerging global problem. Therefore, the present work is conducted that can improve, increase, and integrate the already known issue in literature with new information coming from an emerging country such as Pakistan. The objectives of this study were (i) to assess the urban noise levels and traffic density of Chiniot and Jhang and (ii) to determine nonauditory health effects of noise levels on the residents of both cities. Noise levels were examined from 181 locations (103 from Jhang and 78 from Chiniot) and categorized into hospitals, educational, religious and recreational, residential, industrial areas, and traffic intersections. A-weighted noise level measurements were taken using an integrated sound level meter which recorded short-term road traffic noise continuously for 15 min at each location (LA eq15 ). The urban noise data showed 82% of the sites in Jhang (LA max = 103 dB) and 95% in Chiniot (LA max = 120 dB) exceeded the noise limits set by the National Environment Quality Standard of Pakistan (NEQS-Pak) and World Health Organization (WHO). Moreover, higher intensity of noise levels (LA eq15 ≥ 100 dB) was recorded in Chiniot (17 sites) than in Jhang (1 site). Regression analysis showed a relatively strong relationship of traffic density with noise at Chiniot (R 2 = 0.48) compared to Jhang (R 2 = 0.31). However, spatial variability of noise with traffic density was observed in both cities. Survey study revealed that all the respondents in Jhang and Chiniot suffered from many noise-related health problems such as annoyance (53 and 51%), depression (45 and 47%), dizziness (61 and 65%), headache (67 and 64%), hypertension (71 and 56%), hearing loss (53 and 56%), physiological stress (65 and 65%), sleeplessness (81 and 84%), and tinnitus (70 and 62%) due to noise, respectively. We conclude that noise levels are higher in Chiniot primarily due to high road traffic and secondarily due to high population density. It is recommended that vehicle maintenance and family and urban planning could be effective measures to reduce urban noise levels., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

COVID-19 epidemic has brought wide psychological impacts on the young adults. To investigate the depression and anxiety symptoms and their associations with problematic smartphone use under the COVID-19 epidemic, a total of 847 Chinese undergraduate students joined in this study and were measured with their levels of depression and anxiety symptoms, resilience, perceived social support, the sense of school belonging and problematic smartphone use. Results showed that among the Chinese undergraduate students, the disorder rates of depression and anxiety symptoms were 29.16% and 46.64% respectively, and their symptoms ranged from mild to extreme severe. Depression and anxiety symptoms both positively predicted problematic smartphone use. Resilience, perceived social support and the sense of school belonging partially mediated both associations; resilience and the sense of school belonging exerted buffering effects, while perceived social support exacerbated the impacts. The current study advanced our understanding of the COVID-19 impacts and furthermore, suggested the protective factors for mitigating these impacts., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 Elsevier Ltd. All rights reserved.)

Soil contamination with metallic nanoparticles is increasing due to their increased use in industrial and domestic settings. These nanoparticles are potentially toxic to soil microbes and may affect their associated functions and thereby the nutrient cycling in agro-ecosystems. This study examined the effects of iron oxides nanoparticles (IONPs) on carbon (C) and nitrogen (N) dynamics of poultry (PM) and farmyard manure (FYM) in the soil. The application of IONPs increased iron content in soil microbial biomass, which reflected its consumption by the microbes. As a result, colony-forming units of bacteria and fungi reduced considerably. Such observations lead to a decrease in CO 2 emission from PM and FYM by 27 and 28%, respectively. The respective decrease fractions in the case of N mineralization were 24 and 35%. Consequently, soil mineral N content was reduced by 16% from PM and 12% from FYM as compared to their sole application without IONPs. Spinach dry matter yield and apparent N recovery were increased by the use of organic waste (FYM, PM). The use of IONPs significantly reduced the plant N recovery fraction by 26 and 24% (P < 0.05) from PM and FYM, respectively. All the results mentioned above lead us to conclude that IONPs are toxic to soil microbes and affect their function i.e., carbon and N mineralization of applied manure, and thereby the on-farm N cycling from the manure-soil-plant continuum., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Marigold (Calendula calypso) is a multipurpose ornamental plant, but its cadmium (Cd) tolerance and phytoremediation potential is unknown. The proposed study was carried out to unravel Cd partitioning, physiological and oxidative stress responses of C. calypso grown under Cd stress. Plants were grown for four months in pots having different soil Cd levels: 0, 25, 50, 75, and 100 mg kg -1 soil. Plant growth, biomass, photosynthetic pigments, leaf water contents, stomatal conductance, and membrane stability index were not decreased at 25 mg kg -1 Cd. At higher levels of Cd stress, activities of antioxidant enzymes (SOD, APX, CAT, POD) increased to mitigate H 2 O 2 and lipid peroxidation. Cadmium uptake in plants increased with increasing soil Cd levels, and roots accumulated a greater portion of Cd, followed by shoots and flowers, respectively. On the basis of Cd accumulation and its tolerance, it was determined that C. calypso can be successfully grown for phytostabilization of Cd contaminated soils.

Insect physiology is affected by the presence of toxins in the surrounding environment of insects as well as their food sources. The objective of this study was to determine the effect of heavy metal exposure to two low concentrations (50 μg/g and 150 μg/g) of lead (Pb) and zinc (Zn) through artificial diet to the larvae on biological parameters of Asian armyworm (Spodoptera litura Fabricius) (Lepidoptera: Noctuidae). Both Pb and Zn, even at low concentrations, had relatively high toxic effects on S. litura larvae (P < 0.01). S. litura larval weight and length suffered the maximum reduction when the larvae were fed on diet mixed with the high Pb concentration (150 μg/g) tested compared to the other treatments. At the same Pb concentration (150 μg/g), values of larva growth index, pupa growth index, immature growth index, standardized growth index, and fitness index were 4.66, 7.33, 7.82, 5.35, and 10.00 times lower, respectively, than those of control. At the same Zn concentration (150 μg/g), values of larval growth index, pupal growth index, immature growth index, standardized growth index, and fitness index were 5.61, 3.00, 3.04, 3.23, and 9.24 times lower, respectively, than those of control. The survival rate of S. litura larvae was also lower (12.5%) when the larvae were fed on diet mixed with Pb at 150 μg/g after 10 days of observation. Overall, the presence of those heavy metals in the environment, even at low concentrations, would exert an adverse impact on larvae development of this insect. From this point of view, findings could provide a basis for long-term evaluation of heavy metal risk and its impact on populations of important agricultural pests.

Biomonitoring of people exposed to hazardous materials provides opportunities for early identification of several diseases, particularly in those individuals who are constantly exposed to pesticides, such as pesticide operators and workers in pesticide manufacturing industry. However, data on this hot topic are limited in Pakistan. In this study, insecticide toxic effects and biochemical alterations (i.e., damage in DNA and enzyme activity) were studied in blood samples of occupationally exposed individuals from Punjab, Pakistan. Eight out of twenty-seven blood samples (29.6%) of the pesticide operators were found positive in five insecticides, with the maximum concentration found for chlorpyrifos-methyl (0.039 μg/mL). Eleven out of twenty-seven blood samples (40.7%) of the pesticide industry workers were found positive in eight insecticides, with the maximum concentration found for endosulfan (0.051 μg/mL). Comet tail length was 16.88 ± 4.57 μm in pesticide industry workers and 16.33 ± 3.78 μm in pesticide operators, which were significantly higher (P < 0.01) than that recorded in the control group (4.84 ± 2.21 μm). Values of serum cholinesterase (SChE) concentration were slightly lower (P > 0.05) in exposed individuals, whereas values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) concentration were significantly higher (P < 0.01) in exposed individuals compared with control group. Exposure duration and total insecticide concentration in blood samples were positively associated with comet tail length, ALT activity, AST activity, and ALP activity, but negatively with SChE. DNA damage was higher in smokers vs. non-smokers. Also, a positive association was found between comet tail length and number of cigarettes per day. Overall, occupational exposure to insecticides can pose serious health risks to pesticide operators and workers in pesticide manufacturing industry, highlighting the necessity of personal protection in those groups for preventing exposure and resultant health disorders., (Copyright © 2018. Published by Elsevier B.V.)

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). After a thorough investigation, the Editors have concluded that the acceptance of this article was partly based upon the positive advice of two illegitimate reviewer reports. The reports were submitted from email accounts which were provided by the corresponding author Christos A. Damalas as suggested reviewers during the submission of the article. Although purportedly real reviewer accounts, the Editors have concluded that these were not of appropriate, independent reviewers. This manipulation of the peer-review process represents a clear violation of the fundamentals of peer review, our publishing policies, and publishing ethics standards. Apologies are offered to the reviewers whose identity was assumed and to the readers of the journal that this deception was not detected during the submission process., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Lead (Pb) contamination is ubiquitous and usually causes toxicity to plants. Nevertheless, application of compost and plant growth promoting rhizobacteria synergistically may ameliorate the Pb toxicity in radish. The present study assessed the effects of compost and Bacillus sp. CIK-512 on growth, physiology, antioxidants and uptake of Pb in contaminated soil and explored the possible mechanism for Pb phytotoxicity amelioration. Treatments comprised of un-inoculated control, compost, CIK-512, and compost + CIK-512; plants were grown in soil contaminated with Pb (500mgkg -1 ) and without Pb in pot culture. Lead caused reduction in shoot dry biomass, photosynthetic rate, stomatal conductance, relative water contents, whereas enhanced root dry biomass, ascorbate peroxidase, catalase, malondialdehyde and electrolyte leakage in comparison with non-contaminated control. Plants inoculated with strain CIK-512 and compost produced significantly higher dry biomass, photosynthetic rate and stomatal conductance in normal and contaminated soils. Bacterial strain CIK-512 and compost synergy improved growth and physiology of radish in contaminated soil possibly through homeostasis of antioxidant activities, reduced membrane leakage and Pb accumulation in shoot. Possibly, Pb-induced production of reactive oxygen species resulted in increased electrolyte leakage and malondialdehyde contents (r = 0.88-0.92), which led to reduction in growth (r = -0.97) and physiology (r = -0.38 to -0.80), however, such negative effects were ameliorated by the regulation of antioxidants (r = 0.78-0.87). The decreased activity of antioxidants coupled with Pb accumulation in aerial part of the radish indicates the Pb-phytotoxicity amelioration through synergistic application of compost and Bacillus sp. CIK-512., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The present study is based on cross-sectional data collected from rural and market areas of Vehari District in Pakistan to assess public awareness of pesticide risks and determine the levels of exposure to organochlorine pesticides (OCPs) in the local community. Blood samples were collected from 56 volunteer donors (VDs) including children, female workers, farm workers involved in pesticide business, farm workers involved in pesticide spraying activities, and people who were living away from agricultural fields. Blood analysis showed that VDs who were involved in spraying activities had significantly higher levels of OCP residues in their blood samples than VDs from the other groups, with mean concentrations of 1.13, 0.92, 0.68 and 1.96ngmL -1 for pp-DDT, aldrin, dieldrin, and endosulfan, respectively. However, VDs who were living away from agricultural fields had significantly lower levels of pesticide residues in their blood samples, with mean concentrations of 0.30, 0.19, 0.14 and 0.41ngmL -1 for pp-DDT, aldrin, dieldrin, and endosulfan, respectively. A survey of 179 volunteer respondents (VRs) showed that a significant proportion of the VRs had little knowledge of using the recommended amounts of pesticides (65.9%). Furthermore, the majority of the VRs was found using limited protective measures during pesticide use (62.6%) and was practising unsafe storage of pesticides (87.7%). In addition, most farm workers (88.8%) reported an increasing trend in pesticide use in their farms each year. Knowledge of pesticide risks on human health increased with formal education and training. Poor knowledge regarding pesticide risks and handling among inhabitants of Vehari District contribute to high exposure levels to OCPs, particularly among farm workers. Findings are useful for policy formulation aimed at reduction of pesticide exposure in Pakistan., (Copyright © 2017 Elsevier B.V. All rights reserved.)

We describe a case which had ongoing sepsis, despite adequate incision and drainage performed for an ischorectal abscess. The patient was then noted to have an ascending infection reaching the extraperitoneal space of the abdominal cavity. The case reported required multiple episodes of drainage along with lower midline incision for deep-situated abscess. Postoperatively, the abdominal wound was treated with vacuum-assisted closure dressing and antibiotics. The patient was doing well and was discharged with an appointment at the surgical outpatient department. The report signifies the importance of investigating patients who have systemic inflammatory response syndrome despite treating local abscess., (2017 BMJ Publishing Group Ltd.)

The encephalitic alphaviruses encode nsP2 protease (nsP2pro), which because of its vital role in virus replication, represents an attractive target for therapeutic intervention. To facilitate the discovery of nsP2 inhibitors we have developed a novel assay for quantitative measurement of nsP2pro activity in a cell-based format. The assay is based on a substrate fusion protein consisting of eGFP and Gaussia luciferase (Gluc) linked together by a small peptide containing a VEEV nsp2pro cleavage sequence. The expression of the substrate protein in cells along with recombinant nsP2pro results in cleavage of the substrate protein resulting in extracellular release of free Gluc. The Gluc activity in supernatants corresponds to intracellular nsP2pro-mediated substrate cleavage; thus, providing a simple and convenient way to quantify nsP2pro activity. Here, we demonstrate potential utility of the assay in identification of nsP2pro inhibitors, as well as in investigations related to molecular characterization of nsP2pro., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: The novel high-sensitivity troponin T assay (hs-cTnT) has been validated for diagnosing AMI in the emergency room. However its utility in high-risk in-patient populations is unknown., Methods: We retrospectively reviewed admissions to a general cardiology unit that had 2 hs-cTnT measurements in the first 12 h of presentation. We assessed 8 diagnostic algorithms that used hs-cTnT concentration and changes in concentration (including the 99th percentile cut-off of 14 ng/L) for their diagnostic utility in separating AMI patients from cardiac/nonACS and non-cardiac chest-pain patients. UA was excluded., Results: There were 233 patients (mean age 67 years, 153 were males (66%)) admitted over a 2 month period, with AMI diagnosed in 118 of these patients (51%). The recommended 99th percentile cut-off had modest accuracy (65%), good sensitivity (88%), and poor specificity (25%); a higher cut-off of 75 ng/L had a better diagnostic accuracy of 73%, p < 0.05. While some hs-cTnT algorithms were either highly sensitive or specific, none were both., Conclusion: In high-risk cardiology in-patients, no hs-cTnT concentration cut-off or change more accurately diagnosed and excluded AMI, although higher cut-offs had better diagnostic utility.

Although breast cancer is one of the leading causes of death in women worldwide, there is an overall improvement in the survival of this patient population. This is likely due to a combination of early detection through screening and awareness, improved targeted biological therapy, and an overall improvement in disease management. Despite the beneficial effects of the 2 anti-cancer drugs doxorubicin (DOX) and trastuzumab (TRZ) in women with breast cancer, development of cardiotoxicity is a major concern. The occurrence of left ventricular systolic dysfunction is unacceptably high in nearly 1 in 4 women treated with DOX+TRZ in the breast cancer setting. In this review, we explore the use of non-invasive cardiac imaging for the early detection of chemotherapy-mediated cardiotoxicity in women with breast cancer, in the hope of preventing end-stage heart disease in this cancer population.

Oropouche (ORO) virus, a member of the Simbu serogroup, is one of the few human pathogens in the Orthobunyavirus genus in the family Bunyaviridae. Genetic analyses of ORO-like strains from Iquitos, Peru, identified a novel reassortant containing the S and L segments of ORO virus and the M segment of a novel Simbu serogroup virus. This new pathogen, which we named Iquitos (IQT) virus, was first isolated during 1999 from a febrile patient in Iquitos, an Amazonian city in Peru. Subsequently, the virus was identified as the cause of outbreaks of "Oropouche fever" during 2005 and 2006 in Iquitos. In addition to the identification of 17 isolates of IQT virus between 1999 and 2006, surveys for neutralizing antibody among Iquitos residents revealed prevalence rates of 14.9% for ORO virus and 15.4% for IQT virus. Limited studies indicate that prior infection with ORO virus does not seem to protect against disease caused with the IQT virus infection. Identification of a new Orthobunyavirus human pathogen in the Amazon region of Peru highlights the need for strengthening surveillance activities and laboratory capabilities, and investigating the emergence of new pathogens in tropical regions of South America.

Zaire ebolavirus (ZEBOV), a highly pathogenic zoonotic virus, poses serious public health, ecological and potential bioterrorism threats. Currently no specific therapy or vaccine is available. Virus entry is an attractive target for therapeutic intervention. However, current knowledge of the ZEBOV entry mechanism is limited. While it is known that ZEBOV enters cells through endocytosis, which of the cellular endocytic mechanisms used remains unclear. Previous studies have produced differing outcomes, indicating potential involvement of multiple routes but many of these studies were performed using noninfectious surrogate systems such as pseudotyped retroviral particles, which may not accurately recapitulate the entry characteristics of the morphologically distinct wild type virus. Here we used replication-competent infectious ZEBOV as well as morphologically similar virus-like particles in specific infection and entry assays to demonstrate that in HEK293T and Vero cells internalization of ZEBOV is independent of clathrin, caveolae, and dynamin. Instead the uptake mechanism has features of macropinocytosis. The binding of virus to cells appears to directly stimulate fluid phase uptake as well as localized actin polymerization. Inhibition of key regulators of macropinocytosis including Pak1 and CtBP/BARS as well as treatment with the drug EIPA, which affects macropinosome formation, resulted in significant reduction in ZEBOV entry and infection. It is also shown that following internalization, the virus enters the endolysosomal pathway and is trafficked through early and late endosomes, but the exact site of membrane fusion and nucleocapsid penetration in the cytoplasm remains unclear. This study identifies the route for ZEBOV entry and identifies the key cellular factors required for the uptake of this filamentous virus. The findings greatly expand our understanding of the ZEBOV entry mechanism that can be applied to development of new therapeutics as well as provide potential insight into the trafficking and entry mechanism of other filoviruses.

Objective: The aim of the present study was to evaluate the ease and reliability of the anterior and lateral approaches to sciatic nerve block compared to the posterior parasacral approach, and their suitability for the specific factors in the patients, positions, and surgeries. Also, the insertion and usefulness of the continuous catheter technique was evaluated., Methods: The study was carried out on 120 patients, ASA I, II and III, of both genders, age range between 20 and 70 years, scheduled for orthopedic, general and vascular lower limb surgery. Patients were enrolled in a prospective, randomized, double blind study. Patients were divided into three equal groups, 40 patients each. All the patients received femoral nerve block in addition to sciatic nerve block either parasacral (Posterior group), lateral (Lateral group) or anterior approach (Anterior group). This was followed by continuous femoral and sciatic nerve blocks in the postoperative period. Patients were assessed as regards the time, duration and intensity of the sensory and motor blocks and also the postoperative analgesia offered by the continuous block. They were also assessed for the hemodynamic changes accompanied these blocks. Radiological study was made to demonestrate the spread of different volumes of the drugs alongside the course of the sciatic nerve., Results: The posterior parasacral approach is the easiest technique to perform and used successfully even in obese patients, but difficult to be done, if at all, in patients with limited movement such as multi-pelvic fractures. The anterior approach was found to be the best for the patients in the supine position, with best results as regards patients' satisfaction and sensory and motor blocks. Only, it is a technique that needs high experience especially in obese patients. The lateral approach was the least performed technique especially its high approach. However, it is useful in patients in supine position, and gives the best results in thin patients. The technique showed to be extremely difficult in obese patients., Conclusion: The insertion of a catheter for continuous nerve block was easy. These blocks provided good or excellent postoperative analgesia for all patients in the different groups and facilitated early mobilization which helped in preventing the lower limb srugery - related morbidity and mortality.

While much progress has been made in developing drugs against a few prominent viruses such as HIV, few examples exist for emerging infectious agents. In some cases broad spectrum anti-viral drugs, such as ribavirin, are effective, but for some groups of viruses, these show little efficacy in animal models. Traditional methods focus on screening small molecule libraries to identify drugs that target virus factors, with the intention that side-effects to the host can be minimized. However, this greatly limits potential drug targets and virus genes can rapidly mutate to avoid drug action. Recent advances in siRNA gene targeting technologies have provided a powerful tool to specifically target and suppress the expression of cell genes. Since viruses are completely dependent upon host cell proteins for propagation, siRNA screening promises to reveal novel cell proteins and signaling pathways that may be viable targets for drug therapy regimens. Here we used an siRNA screening approach to identify gene products that play critical roles in Ebola virus infection. By gene cluster analysis, proteins in phosphatidylinositol-3-kinase and calcium/calmodulin kinase related networks were identified as important for Zaire Ebola virus infection and prioritized for further evaluation. Key roles of each were confirmed by testing available drugs specific for members of each pathway. Interestingly, both sets of proteins are also important in cancer and subject to intense investigation. Thus development of new drugs against these cancer targets may also prove useful in combating Ebola virus.

The phosphoinositide-3 kinase (PI3K) pathway regulates diverse cellular activities related to cell growth, migration, survival, and vesicular trafficking. It is known that Ebola virus requires endocytosis to establish an infection. However, the cellular signals that mediate this uptake were unknown for Ebola virus as well as many other viruses. Here, the involvement of PI3K in Ebola virus entry was studied. A novel and critical role of the PI3K signaling pathway was demonstrated in cell entry of Zaire Ebola virus (ZEBOV). Inhibitors of PI3K and Akt significantly reduced infection by ZEBOV at an early step during the replication cycle. Furthermore, phosphorylation of Akt-1 was induced shortly after exposure of cells to radiation-inactivated ZEBOV, indicating that the virus actively induces the PI3K pathway and that replication was not required for this induction. Subsequent use of pseudotyped Ebola virus and/or Ebola virus-like particles, in a novel virus entry assay, provided evidence that activity of PI3K/Akt is required at the virus entry step. Class 1A PI3Ks appear to play a predominant role in regulating ZEBOV entry, and Rac1 is a key downstream effector in this regulatory cascade. Confocal imaging of fluorescently labeled ZEBOV indicated that inhibition of PI3K, Akt, or Rac1 disrupted normal uptake of virus particles into cells and resulted in aberrant accumulation of virus into a cytosolic compartment that was non-permissive for membrane fusion. We conclude that PI3K-mediated signaling plays an important role in regulating vesicular trafficking of ZEBOV necessary for cell entry. Disruption of this signaling leads to inappropriate trafficking within the cell and a block in steps leading to membrane fusion. These findings extend our current understanding of Ebola virus entry mechanism and may help in devising useful new strategies for treatment of Ebola virus infection.

Entry is the first and essential step in virus replication and is a target for therapeutic intervention. However, current knowledge on entry mechanism for the majority of viruses is poor, partly due to lack of a simple, sensitive and accurate entry assay that can be applied to diverse viruses. To overcome this obstacle, a novel contents-mixing-based virus entry assay is described that can be broadly applied to many enveloped viruses. By fusing firefly luciferase to the HIV Nef protein, luciferase was directly packaged into HIV particles pseudotyped with envelope proteins of diverse viruses including HIV, rabies and others. Upon cell entry, the luciferase-fusion protein was released into the cell cytoplasm, reacted with its substrates and was detected by light emission. The assay was validated by demonstrating its versatility in measuring virus entry. Entry was detected much more rapidly (in real-time) with higher sensitivity (a multiplicity of infection <0.1 gives a robust signal) and lower background (signal/noise ration >1000) than other comparable assays. In addition to its utility in studying virus entry mechanisms, the assay will aid in screening potential entry/fusion inhibitors and in diagnosis of virus infections.

Jatobal (JAT) virus was isolated in 1985 from a carnivore (Nasua nasua) in Tucuruí, Pará state, Brazil and was classified as a distinct member of the Simbu serogroup of the Bunyavirus genus, family Bunyaviridae on the basis of neutralization tests. On the basis of nucleotide sequencing, we have found that the small (S) RNA of JAT virus is very similar (>95% identity) to that of Oropouche (ORO) virus, in particular, the Peruvian genotype of ORO virus. In comparison, limited nucleotide sequencing of the G2 protein gene, encoded by the middle (M) RNA, of JAT and ORO viruses, revealed relatively little identity (<66%) between these two viruses. Neutralization tests confirmed the lack of cross-reactivity between the viruses. These results suggest that JAT virus is a reassortant containing the S RNA of ORO virus. JAT virus was attenuated in hamsters compared to ORO virus suggesting that the S RNA of ORO virus is not directly involved in hamster virulence.

The Simbu serogroup of the genus Bunyavirus, family Bunyaviridae contains 25 viruses. Previous serological studies provided important information regarding some but not all of the relationships among Simbu serogroup viruses. This report describes the nucleotide sequence determination of the nucleocapsid (N) gene of the small genomic segment of 14 Simbu serogroup viruses and partial nucleotide sequence determination of the G2 glycoprotein-coding region (encoded by the medium RNA segment) of 19 viruses. The overall phylogeny of the Simbu serogroup inferred from analyses of the N gene was similar to that inferred from analyses of the G2 protein-coding region. Both analyses revealed that the Simbu serogroup viruses have evolved into at least five major phylogenetic lineages. In general, these phylogenetic lineages were consistent with the previous serological data, but provided a more detailed understanding of the relatedness amongst many viruses. In comparison to previous phylogenetic studies on the California and Bunyamwera serogroups of the Bunyavirus genus, the Simbu serogroup displays much larger genetic variation in the N gene (up to 40% amino acid sequence divergence).

Oropouche (ORO) virus is an emerging infectious agent that has caused numerous outbreaks of an acute febrile (dengue-like) illness among humans in Brazil, Peru, and Panama. Diagnosis of ORO virus infection is based mainly on serology. Two different antigens, hamster serum antigen (HSA) and Vero cell lysate antigen (VCLA), are currently used in enzyme immunoassays (EIAs) in Brazil and Peru, respectively, to investigate the epidemiology of ORO virus infection. Both antigens involve use of infectious virus, and for this reason their use is restricted. Consequently, the frequency and distribution of ORO virus infection are largely unexplored in other countries of South America. This report describes the use of a bacterially expressed recombinant nucleocapsid (rN) protein of ORO virus in EIAs for the diagnosis of ORO virus infection. The data revealed that the purified rN protein is comparable to the authentic viral N protein in its antigenic characteristics and is highly sensitive and specific in EIAs. Among 183 serum samples tested, a high degree of concordance was found between rN protein-based EIA and HSA- and VCLA-based EIAs for the detection of both ORO virus-specific immunoglobulin M (IgM) and IgG antibodies. The high sensitivity, specificity, and safety of the rN protein-based EIA make it a useful diagnostic technique that can be widely used to detect ORO virus infection in South America.

The nucleotide sequence of the S RNA segment of the Oropouche (ORO) virus prototype strain TRVL 9760 was determined and found to be 754 nucleotides in length. In the virion-complementary orientation, the RNA contained two overlapping open reading frames of 693 and 273 nucleotides that were predicted to encode proteins of 231 and 91 amino acids, respectively. Subsequently, the nucleotide sequences of the nucleocapsid genes of 27 additional ORO virus strains, representing a 42 year interval and a wide geographical range in South America, were determined. Phylogenetic analyses revealed that all the ORO virus strains formed a monophyletic group that comprised three distinct lineages. Lineage I contained the prototype strain from Trinidad and most of the Brazilian strains, lineage II contained six Peruvian strains isolated between 1992 and 1998, and two strains from western Brazil isolated in 1991, while lineage III comprised four strains isolated in Panama during 1989.

Binding of yellow fever virus wild-type strains Asibi and French viscerotropic virus and vaccine strains 17D and FNV to monkey brain and monkey liver cell membrane receptor preparations (MRPs) was investigated. Only FNV bound to monkey brain MRPs, while French viscerotropic virus, Asibi, and FNV all bound to monkey liver MRPs. Four monkey brain and two mouse brain MRP escape (MRP(R)) variants of FNV were selected at pH 7.6 and 6.0. Three monkey brain MRP(R) variants selected at pH 7.6 each had only one amino acid substitution in the envelope (E) protein in domain II (E-237, E-260, or E274) and were significantly attenuated in mice following intracerebral inoculation. Two of the variants were tested in monkeys and retained parental neurotropism following intracerebral inoculation at the dose tested. We speculate that this region of domain II is involved in binding of FNV E protein to monkey brain and is, in part, responsible for the enhanced neurotropism of FNV for monkeys. A monkey brain MRP(R) variant selected at pH 6.0 and two mouse brain MRP(R) variants selected at pH 7.6 were less attenuated in mice, and each had an amino acid substitution in the transmembrane region of the E protein (E-457 or E-458).

Glucocorticoids (GCs) induce apoptosis in lymphoid cells that contain functional GC receptors (GRs). However, GC resistance often is seen in cells with demonstrable GRs; one such line is CEM-C1. We have tested the hypothesis that positive interactions between GC and cyclic AMP (cAMP) regulate GC actions in CEM clones. Treatment of both GC-resistant CEM-C1 [resistant to 1 microM dexamethasone (Dex)] and the sensitive sister clone, CEM-C7 (approximately 65% cell death with 20 nM Dex, approximately 99% death with 1 microM Dex), with a < or = 20 microM concentration of the protein kinase A activator, forskolin, had no significant effect on cell viability. Cotreatment with Dex and forskolin resulted in a strong synergistic death response, with only approximately 10% CEM-C1 cells surviving treatment with 1 microM Dex and 20 microM forskolin. This death was blocked by the GR antagonist RU 38486. However, the extent of apoptosis did not correlate with the amount of GR protein or binding activity in either C7 or C1 cells. As reported previously, Dex-evoked cell death was associated with suppression of c-Myc in C7 cells. In CEM-C1 cells, Dex alone did not affect c-Myc; however, Dex plus forskolin suppressed c-Myc levels. To evaluate mechanisms of Dex-forskolin synergism, fresh subclones of CEM-C7 (clone 14) and CEM-C1 (clone 15) were isolated, to ensure purity of phenotype. In these, forskolin (with or without Dex) caused a similar increase in cAMP (approximately 300-fold) and phospho-cAMP-responsive element binding protein (approximately 4-5-fold) levels, whereas total cAMP-responsive element binding protein expression was not affected. GR transcription function, as tested from a GR-responsive 330-bp mouse mammary tumor virus promoter-luciferase reporter construct, was induced 8- and 4-fold by 1 microM Dex treatment of CEM-C7-14 and CEM-C1-15 cells, respectively. Forskolin (10 microM) significantly potentiated Dex response in CEM-C1-15 cells (13.5-fold) but had only a modest effect (1.5-fold) in CEM-C7-14 cells. These studies suggest that sensitization of CEM-C1 cells by cross-talk between GR and protein kinase A pathways may occur via cooperative effects on GR-mediated gene transcription.

A synthetic glucocorticoid dexamethasone (DEX) inhibits proliferation and induces apoptosis of clone CEM-C7 cells, but not in clone CEM-C1 cells, even though they contain glucocorticoid receptors (GR). We previously showed that suppression of c-myc is a critical step in glucocorticoid-induced cell lysis of C7 cells. It is not reduced in C1 cells. In this study we review the basis for this conclusion and present evidence that the glucocorticoid antagonist RU 486 rescues DEX-treated C7 cells from cell death. An increase in DEX-repressed c-myc mRNA levels precedes the recovery of cell growth. A threshold level of Myc expression appears to be required to maintain growth and viability of C7 cells. Although C1 cells are highly resistant to lysis by glucocorticoids, addition of forskolin, an inducer of protein kinase A, synergizes to evoke complete apoptosis. This synergistic effect is prevented by RU 486, indicating direct involvement of the GR.