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BACKGROUND: Crops genetically engineered to make insect-killing proteins from Bacillus thuringiensis (Bt) have revolutionized management of some pests. However, the benefits of such transgenic crops are reduced when pests evolve resistance to Bt toxins. We evaluated resistance to Bt toxins and Bt cotton plants using laboratory bioassays and complementary field trials focusing on Helicoverpa zea, one of the most economically important pests of cotton and other crops in the United States. RESULTS: The data from 235 laboratory bioassays demonstrate resistance to Cry1Ac, Cry1Fa, and Cry2Ab occurred in most of the 95 strains of H. zea derived from Arkansas, Louisiana, Mississippi, Tennessee, and Texas during 2016 to 2021. Complementary field data show efficacy decreased for Bt cotton producing Cry1Ac + Cry1Fa or Cry1Ac + Cry2Ab, but not Cry1Ac + Cry1Fa + Vip3Aa. Moreover, analysis of data paired by field site and year shows higher survival in bioassays was generally associated with lower efficacy of Bt cotton. CONCLUSIONS: The results confirm and extend previous evidence showing widespread practical resistance of H. zea in the United States to the Cry toxins produced by Bt cotton and corn, but not to Vip3Aa. Despite deployment in combination with Cry toxins in Bt crops, Vip3Aa effectively acts as a single toxin against H. zea larvae that are highly resistant to Cry toxins. Furthermore, Vip3Aa adoption is increasing and previous work provided an early warning of field-evolved resistance. Thus, rigorous resistance management measures are needed to preserve the efficacy of Vip3Aa against this highly adaptable pest. © 2022 Society of Chemical Industry.

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Foliar-applied insecticide treatments may be necessary to manage thrips in cotton (Gossypium hirsutum L.) under severe infestations or when at-planting insecticide seed treatments do not provide satisfactory protection. The most common foliar-applied insecticide is acephate. Field observations in Tennessee suggest that the performance of acephate has declined. Thus, the first objective was to perform leaf-dip bioassays to assess if tobacco thrips, Frankliniella fusca (Hinds) (Thysanoptera: Thripidae), in cotton production regions have evolved resistance to foliar-applied insecticides. A second objective was to assess the performance of commonly applied foliar insecticides for managing thrips in standardized field trials in Arkansas, Tennessee, Mississippi, and Texas. For both objectives, several insecticides were evaluated including acephate, dicrotophos, dimethoate, lambda-cyhalothrin, imidacloprid, and spinetoram. Field trials and bioassays were completed from 2018 to 2021. Dose-response bioassays with acephate were performed on tobacco thrips field populations and a susceptible laboratory population. Bioassay results suggest that tobacco thrips have developed resistance to acephate and other organophosphate insecticides; however, this resistance seems to be most severe in Arkansas, Tennessee, and the Delta region of Mississippi. Resistance to other classes of insecticides were perhaps even more evident in these bioassays. The performance of these insecticides in field trials was variable, with tobacco thrips only showing consistent signs of resistance to lambda-cyhalothrin. However, it is evident that many populations of tobacco thrips are resistant to multiple classes of insecticides. Further research is needed to determine heritability and resistance mechanism(s).

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Widespread field-evolved resistance of bollworm [Helicoverpa zea (Boddie)] to Cry1 and Cry2 Bt proteins has threatened the utility of Bt cotton for managing bollworm. Consequently, foliar insecticide applications have been widely adopted to provide necessary additional control. Field experiments were conducted across the Mid-South and in Texas to devise economic thresholds for foliar insecticide applications targeting bollworm in cotton. Bt cotton technologies including TwinLink (TL; Cry1Ab+Cry2Ae), TwinLink Plus (TLP; Cry1Ab+Cry2Ae+Vip3Aa), Bollgard II (BG2; Cry1Ac+Cry2Ab), Bollgard 3 (BG3; Cry1Ac+Cry2Ab+Vip3Aa), WideStrike (WS; Cry1Ac+Cry1F), WideStrike 3 (WS3; Cry1Ac+Cry1F+Vip3Aa), and a non-Bt (NBT) variety were evaluated. Gain threshold, economic injury level, and economic thresholds were determined. A 6% fruiting form injury threshold was selected and compared with preventive treatments utilizing chlorantraniliprole. Additionally, the differences in yield from spraying bollworms was compared among Bt cotton technologies. The 6% fruiting form injury threshold resulted in a 25 and 75% reduction in insecticide applications relative to preventive sprays for WS and BG2, respectively. All Bt technologies tested in the current study exhibited a positive increase in yield from insecticide application. The frequency of yield increase from spraying WS was comparable to that of NBT. Significant yield increases due to insecticide application occurred less frequently in triple-gene Bt cotton. However, their frequencies were close to the dual-gene Bt cotton, except for WS. The results of our study suggest that 6% fruiting form injury is a viable threshold, and incorporating a vetted economic threshold into an Integrated Pest Management program targeting bollworm should improve the sustainability of cotton production.

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Sugarcane aphid Melanaphis sacchari Zehntner is a significant economic pest of grain sorghum in the United States. Effective monitoring and early detection are cornerstones for managing invasive pests. The recently developed binomial sequential sampling plan estimates sugarcane aphid economic thresholds (ETs) based on classification whether a 2-leaf sample unit has ≤ or ≥ 50 M. sacchari. In this study, we evaluated eight 2-leaf sampling units for potential use in the sequential sampling plan. From 2016 through 2017, whole plant counts of M. sacchari were recorded non-destructively in situ on sorghum plants from 140 fields located in five states. Plant canopies were stratified into three categories. Two leaves from each stratum were used to compare linear relationships between M. sacchari numbers per two-leaf sample unit and total M. sacchari density per plant. Analysis revealed that two randomly selected leaves from the middle stratum accounted more variation for estimating M. sacchari density when compared to two leaves from the other strata. Comparison of eight two-leaf sampling units within plant growth stages were variable in quantifying variation of M. sacchari densities. When growth stages were combined, the standard uppermost + lowermost leaf sample unit and a unit consisting of two randomly selected leaves from the middle stratum revealed little difference in their enumeration of variation in M. sacchari density. Because other sample units were either less predictive and/or more variable in estimating M. sacchari density, we suggest that the (L1+U1) sample unit remain the preferred method for appraising M. sacchari ETs.

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The sugarcane aphid (Melanaphis sacchari Zehntner) is a significant economic pest of grain sorghum (Sorghum bicolor (L.) Moench) in the Southern United States. Current nominal and research-based economic thresholds are based on estimates of mean aphids per leaf. Because enumerating aphids per leaf is potentially time consuming, binomial sequential sampling plans for M. sacchari were developed that allow users to quickly classify the economic status of field populations and determine when an economic threshold has been exceeded. During 2016 and 2017, counts of M. sacchari were recorded from 281 sampling events in 140 sorghum fields located in six states (Oklahoma, Kansas, Texas, Arkansas, Louisiana, Mississippi) . Regression analysis was used to describe the relationships between the mean M. sacchari density per two-leaf sample and proportion of plants infested with one or more aphids. Tally thresholds of T50 and T100 aphids per two-leaf sample were selected based on goodness of fit and practicality. Stop lines for both tally thresholds were developed for selected economic thresholds using Wald's sequential probability ratio test. Model validations using an additional 48 fields demonstrated that reliable classification decisions could be made with an average of 11 samples regardless of location. This sampling system, when adopted, can allow users to easily and rapidly determine when M. sacchari infestations need to be treated.

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BACKGROUND: Many unknown risk factors play a role in the etiopathogenesis of stroke. The appearance of inflammatory cells within the damaged tissue after cerebral ischemia suggests that an inflammatory response may play a role in stroke pathogenesis. In our study, we examined whether an association exists between the acute-phase reactants and the levels of cytokines, the volume and diameter of the stroke, and short-term mortality in patients who were diagnosed as acute ischemic a stroke after admission to the Emergency Department. PATIENTS AND METHODS: A total of 50 consecutive patients who applied to the Emergency Service with acute ischemic stroke were enrolled in the study. Their stroke volume were calculated and serum samples were obtained as soon as they arrived into the Emergency Service. The patients were evaluated according to the Glasgow Coma Scale (GCS) and National Institutes of Health Stroke Scale (NIHSS). RESULTS: There was no significant correlations between stroke volume and levels of cytokine and acute-phase reactants in dead patient group or in living patient group. A correlation and statistical significance was found between stroke volume and hospital stay time in living patient group. In addition, GCS and NIHSS scores were correlated with stroke volume and was found a significant statistically. CONCLUSIONS: Scales such as GKS and NIHHS, which evaluate the functional state of patients, are the best indicators for defining prognosis in our daily practices. In addition, we found a positive correlation between levels of CRP (C reactive protein) and prognosis. However, we did not observe a statistically significant correlation between prognosis and other acute-phase reactants such as TNF-alpha, IL-6, IL-8, IL-10, fibrinogen, and leukocytes.

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Avaliaram-se as alterações morfológicas, morfométricas e ultraestruturais que ocorreram no baço devido à isquemia produzida pelo clampeamento total do pedículo hepático. Para tanto, foram utilizados 40 ratos machos, distribuídos em quatro grupos de 10 animais. O grupo-controle (C) não foi submetido à isquemia, e os grupos tratados (E1, E2e E3) foram submetidos ao clampeamento por 10, 20 e 30 minutos, respectivamente. Fragmentos do baço foram retirados e analisados histologicamente pela microscopia de luz (hematoxilina-eosina, ferrocianeto-férrico) e pela microscopia eletrônica de transmissão. Os resultados demonstraram que 10 minutos de clampeamento do pedículo hepático são suficientes para apresentar sinais de congestão esplênica e 20 e 30 minutos promovem intensa digestão de hemácias pelos macrófagos, com presença de grânulos de ferro (hemossiderina) no parênquima esplênico.

The macro and microscopic alterations that occurred in the spleen during an ischemia produced by the hepatic pedicle total clamping were studied. Forty male rats were distributed in four groups of 10 animals each. The control group (C) was not submitted to ischemia and the treated groups (E1, E2, and E3) were submitted to the clamping during 10, 20, and 30 minutes, respectively. Spleen fragments were collected and histologically analyzed by the light microscopy (eosin-hematoxilin and ferric ferrocyanide) and by the transmission electron microscopy. The results showed that 10 minutes of hepatic pedicle total clamping was enough produce signs of splenic congestion and 20 and 30 minutes promoted intense red bood cels digestion by the macrophages with the presence of iron granules (hemosiderin) in the splenic parenchyma.

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Scorpions are nocturnal arthropods that inject their venom through the victims' skin by stingers. By the envenomation, clinical manifestations in a wide spectrum may occur, including pain at one side and death because of severe cardiopulmonary or neurological abnormalities. Sometimes the victim cannot describe the insect or does not remember even being stung after the event. We present two cases of scorpion envenomation with different and rare clinical situations with a short review of the literature.

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BACKGROUND: Plasminogen activator inhibitor-1 (PAI-1) regulates normal extracellular matrix (ECM) metabolism and it is a key regulator of the fibrotic process. Both angiotensin II (Ang II) and angiotensin IV (Ang IV) have been reported to stimulate PAI-1 expression. It is not known how PAI-1 expression is regulated by the renin-angiotensin system (RAS) in renal tubular cells. METHODS: To dissect signaling mechanisms contributing to the up-regulation of the PAI-1 promoter, porcine proximal tubular cells stably expressing the rabbit AT1 receptor (LLC-PK/AT1) were transiently transfected with a luciferase reporter construct containing the PAI-1 promoter. Promoter activation was assessed by measuring luciferase activity from cell lysates. RESULTS: Ang II dose-dependently stimulated the transcriptional activity of the PAI-1 promoter in renal proximal tubular cells whereas Ang IV had no consistent effect on the promoter activity. Neither inhibition of the Extracellular Signal Regulated Kinase (ERK) cascade nor inhibition of the c-Jun-N-terminal Kinase (JNK) pathway did reduce the stimulation of the PAI-1 promoter by Ang II. However, genistein, a tyrosine kinase inhibitor blocked the effect of Ang II. CONCLUSION: Ang II but not Ang IV activates the PAI-1 promoter in renal proximal tubular cells and this effect is mediated by tyrosine kinases.

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Hydatid disease is a parasitic infection caused by Echinococcus granulosus characterised by cyst formation in any organ, although the liver is the most commonly involved. Hydatid cysts can rupture either spontaneously or following trauma. Surgical treatment can be life-saving. This paper reports the atypical presentation of a young girl admitted to the emergency department. She presented with pain on her palms due to falling down a few steps. Because of the rebound tenderness on the right upper quadrant of her abdomen on physical examination, bedside ultrasonography was performed to identify the underlying cause, and promptly revealed a 62 x 72 mm lobular cyst on the right lobe of the liver with free fluid in the subcapsular area. Shortly afterwards, urticaria developed. Fluid resuscitation, methylprednisolone and diphenylhydramine were administered intravenously. Afterwards she was taken to the operation room for unroofing, drainage and capitonage. In conclusion, primary care and emergency physicians should perform a complete physical examination on all admitted patients with vague symptoms and a high index of suspicion for a ruptured hydatid cyst, even following trivial trauma, especially in endemic regions.

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OBJECTIVE: To evaluate medical and surgical residents' anger levels with regard to the department in which they worked, seniority, sex, satisfaction with their work environment, and the number of nightshifts worked per month. The specific situations and persons at whom residents reacted with anger were also investigated. METHODS: 116 randomly selected residents staffed in a university hospital (62 medical and 54 surgical residents) were enrolled. The trait anger and anger expression scale was used to find out the personal anger levels of each participant. The participants also clarified the persons and situations that made them angry at work. RESULTS: Trait anger levels were greater in the surgical residents in their first two years when compared with levels of their senior colleagues (p = 0.033). Mean trait anger levels were greater in the residents who were not satisfied with their department (p = 0.004). Anger levels were not found to be related to the number of shifts per month. Male residents had higher levels of anger than female colleagues (p = 0.019). CONCLUSION: Residents in clinical sciences seem to have the potential to benefit from a screening process in terms of anger and its subcomponents by means of a tool such as the trait anger and anger expression scale during their residency.

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Little is known about snakebites during pregnancy and only a few cases have been reported in the literature. The fact that venomous snakebites during pregnancy result in high fetal wastage and may cause maternal mortality makes this an important, albeit, uncommonly encountered entity in emergency medicine. In this paper, we report on the successful treatment of three cases of snakebite in pregnancy.

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Nearly everyone is at risk of acute and chronic toxic exposure to hazardous substances in the ambient environment. Morbidity and mortality following an overdose are reduced by intensive appropriate supportive therapy. A well-trained medical team is required for the administration of intensive clinical care, which includes enough equipment for monitoring the patient's status. In this paper we present a student who, after attending a dentist faculty, ingested 100 grams of pure inorganic mercury in order to commit suicide and was treated with forced diuresis, whole bowel irrigation, and D-penicillamine. The latter was found following 48 hours of therapy and only used for 4 days because of lack of availability of other antidotes for mercury in our city.

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PURPOSE: The feasibility and clinical outcome of intra-arterial thrombolysis followed by carotid endarterectomy (CEA) for acute thrombotic occlusion of the internal carotid artery (ICA) were evaluated. METHODS: Intra-arterial thrombolysis and CEA were performed in four patients with acute thrombotic ICA occlusion. Computed tomography scans, cerebral angiograms, and the severity of carotid plaques were examined, and the patients' clinical outcome was evaluated. RESULTS: All 4 patients had severe hemiparesis; 3 patients were alert, and 1 patient was lethargic at the time of hospital admission. New lesions were not shown by means of the initial computed tomography scan. ICA occlusion was indicated in all four patients by means of cerebral angiograms; in three patients, middle cerebral artery occlusion was noted. Collateral circulation was manifested in all patients. Partial recanalization of the occluded ICA was obtained in all patients. Two patients with severe residual ICA stenosis underwent an emergency CEA soon after thrombolysis; the other two patients were treated by means of CEA in the subacute or chromic stage. Plaque rupture and intraplaque hemorrhage were seen in all four patients. All four patients recovered completely, and restenosis of the ICA was not shown by means of follow-up angiograms. CONCLUSION: Intra-arterial thrombolysis followed by CEA may be an effective therapeutic approach for treating acute thrombotic ICA occlusion. The optimal timing of CEA remains controversial.

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Ecbalium elaterium, known as the wild or squirting cucumber, is a hairy perennial herbaceous vine of the Cucurbitaceae family, endemic to the Mediterranean region. All parts of the plant are toxic, particularly the gherkin-like fruits. It is frequently used in the treatment of sinusitis by nasal aspiration in some parts of the Mediterranean. The studies regarding to Ecbalium elaterium, argue that it has an anti-inflammatory characteristic. Two cases of uvular oedema have been ascribed to the undiluted use of this substance. Since they can threaten life, similar cases arising with the improper use of herbals should not be ignored in the emergency department. In this paper we present a life-threatening uvular angioedema caused by nasal aspiration of undiluted juice of squirting cucumber.

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A 41-year-old male was admitted to our service with right occipital pain as his chief complaint. CT and MRI examinations revealed bilateral chronic subdural hematomas. The patient had also been affected with ITP since the age of 28. Since emergency operation was thought to be dangerous, he was transferred to Tokushima University Hospital, and treated preoperatively by administration of steroids and a large dose of immunoglobulin. When his platelet count had returned to 146,000/mm3, evacuation of the hematoma through burr holes was performed successfully under local anesthesia. The postoperative course was uneventful. So far as we have been able to find in the literature, only 3 cases of ITP complicated by chronic subdural hematoma have been reported. The characteristic clinical feature of these 4 cases including our own case was noted as the absence of a history of trauma. However, the etiological relationship between ITP and chronic subdural hematoma was controversial. Occurrence of chronic subdural hematoma in patients with ITP and in patients under hemodialyzer treatment is very rare. However, intracerebral hemorrhages are rather common among such patients. So it was suggested that the tendency to bleeding among patients with ITP, and among hemodialyzer patients may contribute little as an etiological factor in the evolution of chronic subdural hematoma.

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