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Helicoverpa zea is a major target pest of Bt corn and Bt cotton. Field-evolved resistance of H. zea to Cry1 and Cry2 proteins has been widely reported in the United States. Understanding the frequency of resistance alleles in a target insect is critical for Bt resistance management. Despite multiple cases of practical resistance to Cry proteins having been documented in H. zea, there are no data on the current status of alleles conferring resistance to Cry1Ac and Cry2Ab2 in field populations of this pest. During 2018-2019, a total of 106 F2 families for Cry1Ac and 120 F2 families for Cry2Ab2 were established using mass mating and light trap strategy. We screened 13,568 and 15,360 neonates using a discriminatory dose of Cry1Ac and Cry2Ab2, respectively. The results showed that 93.4% and 35.0% of the F2 families could survive on the discriminatory dose of Cry1Ac and Cry2Ab2, respectively. The estimated resistance allele frequency for Cry1Ac in H. zea ranged from 0.4150 to 0.4975 and for Cry2Ab2 ranged from 0.1097 and 0.1228. These data indicate that the frequency of alleles conferring resistance to Cry1 and Cry2 proteins in H. zea in Texas are high. In addition, our data suggest the resistance to Cry1Ac and Cry2Ab2 in the screened families of H. zea varies from recessive to dominant. The information in this study provides precise estimates of Cry resistance allele frequencies in H. zea and increases our understanding of the risks to the sustainability of Bt crops.

Fil: Santiago, Cintia Cecilia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Quimica. Laboratorio de Estudio de Compuestos Organicos; Argentina

Fil: Lafuente, Maria Leticia. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Quimica. Laboratorio de Estudio de Compuestos Organicos; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - La Plata; Argentina

The bacterial cell wall, composed of peptidoglycan (PG), provides structural integrity for the cell and is responsible for cell shape in most bacteria. Here we present tools to study the cell wall using a clickable PG-specific sugar, 2-alkyne muramic acid (MurNAc-alk), as a metabolic probe. Here we present a new reaction pathway for generating MurNAc-alk. We also include protocols for labeling PG synthesis in Helicobacter pylori, determining the identity of the labeled muropeptides using LC-MS/MS, sample preparation of cells labeled for a short fraction of the doubling time, and visualization using 3D structured illumination microscopy. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Alternative synthesis of MurNAc-alk (direct coupling) Support Protocol 1: Growing Helicobacter pylori in liquid culture Support Protocol 2: Fosfomycin rescue assay Basic Protocol 2: Mass spectrometry (MS) analysis to determine incorporation of MurNAc-alk within the peptidoglycan of H. pylori Support Protocol 3: Hayashi test to determine if SDS is present in the supernatant of peptidoglycan preparations Support Protocol 4: Creating custom cytocentrifuge units for use in a swinging-bucket tabletop centrifuge Basic Protocol 3: Labeling H. pylori with MurNAc-alk or D-Ala-alk Basic Protocol 4: Structured illumination microscopy (SIM) imaging on the DeltaVision OMX.

Producción Científica, The construction of position dependent mass Scarf Hamiltonians of the trigonometric as well as the hyperbolic types is addressed by means of the factorization method and the Riccati equation. These Hamiltonians are shown to be independent of the ordering parameter of the kinetic term. Additionally, new families of Hamiltonians with the Scarf spectrum are also determined by supersymmetry. Some examples for masses with and without singularities are considered to illustrate our results.

Bacterial cells utilize small carbohydrate building blocks to construct peptidoglycan (PG), a highly conserved mesh-like polymer that serves as a protective coat for the cell. PG production has long been a target for antibiotics, and its breakdown is a source for human immune recognition. A key component of bacterial PG, N-acetyl muramic acid (NAM), is a vital element in many synthetically derived immunostimulatory compounds. However, the exact molecular details of these structures and how they are generated remain unknown due to a lack of chemical probes surrounding the NAM core. A robust synthetic strategy to generate bioorthogonally tagged NAM carbohydrate units is implemented. These molecules serve as precursors for PG biosynthesis and recycling. Escherichia coli cells are metabolically engineered to incorporate the bioorthogonal NAM probes into their PG network. The probes are subsequently modified using copper-catalyzed azide-alkyne cycloaddition to install fluorophores directly into the bacterial PG, as confirmed by super-resolution microscopy and high-resolution mass spectrometry. Here, synthetic notes for key elements of this process to generate the sugar probes as well as streamlined user-friendly metabolic labeling strategies for both microbiology and immunological applications are described. © 2019 by John Wiley & Sons, Inc. Basic Protocol 1: Synthesis of peracetylated 2-azido glucosamine Basic Protocol 2: Synthesis of 2-azido and 2-alkyne NAM Basic Protocol 3: Synthesis of 3-azido NAM methyl ester Basic Protocol 4: Incorporation of NAM probes into bacterial peptidoglycan Basic Protocol 5: Confirmation of bacterial cell wall remodeling by mass spectrometry.

Several countries have local transmission of multiple arboviruses, in particular, dengue and Zika viruses, which have recently spread through many American countries. Cross reactivity among Flaviviruses is high and present a challenge for accurate identification of the infecting agent. Thus, we evaluated the level of cross reactivity of anti-dengue IgM/G Enzyme-Linked Immunosorbent Assays (ELISA) from three manufacturers against 122 serum samples obtained at two time-points from 61 patients with non-dengue confirmed Zika virus infection. All anti-dengue ELISAs cross reacted with serum from patients with acute Zika infection at some level and a worrisome number of seroconversion for dengue IgG and IgM was observed. These findings may impact the interpretation of currently standard criteria for dengue diagnosis in endemic regions.

OBJECTIVES The purpose of this study was to estimate the utility of sonography to detect small-for-gestational-age (SGA) neonates in pregnancies with gastroschisis and to evaluate neonatal outcomes according to birth weight percentile. METHODS We conducted a retrospective cohort study of singleton pregnancies with fetal gastroschisis delivered at our hospital between August 1997 and December 2012. Diagnosis of growth restriction was based on estimated fetal weight below the 10th percentile using the nomogram of Hadlock et al (Am J Obstet Gynecol 1985; 151:333-337), evaluated at 4-week intervals throughout gestation and compared with subsequent birth weight, to evaluate the accuracy of sonography to detect and exclude SGA neonates. Pregnancy and neonatal outcomes were evaluated according to birth weight percentile. RESULTS There were 111 births with gastroschisis (6 per 10,000), and one-third (n = 37) had birth weight below the 10th percentile. The sensitivity and negative predictive value of sonography for an SGA neonate both approached 90% by 32 weeks and were approximately 95% thereafter. Detection increased with advancing gestational age (P = .02). The birth weight percentile was not associated with preterm birth, infection, bowel complications requiring surgery, duration of hospitalization, or perinatal mortality. Delayed closure of the gastroschisis defect was more frequent with birth weights at or below the 3rd percentile (P = .03). CONCLUSIONS Sonography reliably identified SGA neonates with gastroschisis in our series, and its utility improved with advancing gestation. Apart from delayed closure of the defect, a low birth weight percentile was not associated with an increased risk of morbidity or mortality in the immediate neonatal period.

When medical therapy fails for menorrhagia in a premenopausal woman, minimally invasive endometrial ablation can be used as a conservative management alternative to hysterectomy. Endometrial ablation alone is not considered effective contraception, and women of reproductive age can become pregnant after ablative therapy. We now present two cases of pregnancy after endometrial ablation and associated imaging where both cases required cesarean hysterectomy due to post-partum hemorrhage. Pregnancy after endometrial ablation incurs increased morbidity and diagnostic dilemmas.

Backfat thickness affects the preservation of the beef carcass after slaughter and confers organoleptic characteristics assessed by the consumer. One of the breeding goals for Canchim, a tropically adapted breed, is to comprehensively increase fat thickness. Our goals were to identify genomic regions associated with backfat in Canchim populations and validate the association of single nucleotide polymorphisms (SNPs) overlapping previously identified QTL regions known to affect fat deposition. Fifteen animals with lower and 15 animals with higher residues for backfat, according to a linear model using the SAS GLM procedure, were selected from a population of 1171 animals and genotyped using the BovineSNP50 BeadChip. Initial analysis revealed more than 100 SNPs that discriminated the tails of phenotypic distribution. One extended region of association included the centromeric region of chromosome (Chr) 14. Because this region overlapped with QTL from previous reports, we developed SNP assays to interrogate two linkage disequilibrium blocks, one in the centromeric region and another in the middle region of Chr 14 to confirm the association. The analysis validated the presence of specific haplotypes affecting fat thickness.

The spleen is a secondary lymphoid organ that harbours a variety of cells such as T and B lymphocytes and antigen-presenting cells important to immune response development. In this study, we evaluated the impact of spleen removal in the immune response to experimental Trypanosoma cruzi infection. C57BL/6 mice were infected with Y strain of the parasite and infection was followed daily. Mice that underwent splenectomy had fewer parasites in peripheral blood at the peak of infection; however, mortality was increased. Histological analysis of heart and liver tissues revealed an increased number of parasites and inflammatory infiltrates at these sites. Spleen removal was associated with reduction in IFN-γ and TNF-α production during infection as well as with a decrease in specific antibody secretion. Haematological disorders were also detected. Splenectomized mice exhibited severe anaemia and decreased bone marrow cell numbers. Our results indicate that spleen integrity is critical in T. cruzi infection for the immune response against the parasite, as well as for the control of bone marrow haematological function.

The compounds (BH)4Mo8O26 being B: anilinium, N-methylanilinium, N,N-dimethylanilinium and N,N-diethylanilinium have been synthetized and characterized for the first time. Thermogravimetric decomposition in isothermal and non-isothermal regime have been studied. At temperatures between 480–560 K a great number of organic compounds, different from the initial organic bases have been identified, with molecular weight between 117–254 g mol−1.

Objective To analyze various possibilities of using dimeric inhibin A (DIA) as a first-trimester marker, during week 13, for diverse sequential strategies together with the combined test (CT) [which uses pregnancy-associated plasma protein A, free beta-human chorionic gonadotrophin and nuchal translucency]. Method We analyzed three sequential strategies (nondisclosure, stepwise and contingent) for measuring DIA in week 13. Multivariate Gaussian modelling was used to estimate second-trimester, false-positive and detection rates. Model parameters were taken from the Serum, Urine and Ultrasound Screening Study (SURUSS) assay. Results The three sequential strategies provided high and comparable levels of effectiveness, with false-positive rate for fixed detection rate of 85% and detection rate for fixed false-positive rate of 5% values of about 91 and 2%, respectively. The contingent strategy (with two CT risk cutoffs, of 1 in 50 and 1 in 2000) produced a screening-positive rate of 0.8% with CT, while only 23% of the women needed subsequent DIA measurement. Conclusions First-trimester sequential screening using CT together with DIA measurement in week 13 is capable of producing results that are comparable with those of the integrated test, with the additional advantage that the final result is obtained earlier. It is recommended that this strategy be evaluated in large-scale prospective studies. Copyright © 2008 John Wiley & Sons, Ltd.

Highly significant changes were found in digenean metacercariae infected gills of killifish Fundulus heteroclitus with respect to gill abnormalities. Gills infected with >1000 metacercariae exhibited up to 42 additional gill branches per fish when compared to less parasitized conspecifics. A strong positive correlation was found between abnormal gill morphology (number of branches) and the number of endoparasites present.

Objectives Two methods have been proposed for standardizing measures of nuchal translucency thickness (NT) for risk calculation in first-trimester screening for chromosomal defects: differential delta NT (delta-NT) and multiples of the median (MoM) of NT. There is currently some debate as to which of these is more appropriate. The aims of this study were to determine whether delta-NT could be extrapolated successfully from one center-specific NT reference curve to another and thus to empirically calculate the likelihood ratios (LRs) of delta-NT. Methods This was a retrospective analysis of a database of 4248 singleton pregnancies, including 13 cases of Down syndrome. The delta-NT was extrapolated to the reference curve of the NT values of the original group of patients for whom the LRs were calculated empirically, using a scale factor. The Down syndrome risk was calculated by standardizing the NT, using both extrapolated delta-NT and MoM methods, both for the screening based on maternal age and NT alone, and for the combined screening, in which biochemical markers are also taken into account. We analyzed detection rates and false positives, the precision of the risk prediction obtained by each of the methods and the effectiveness when each of the methods was used with a cut-off point based on a fixed post-test risk. Results The risk calculation using extrapolated delta-NT presented an effectiveness profile that was similar to that obtained using MoMs, both when NT was used as the sole marker and when it was used in combination with biochemical markers. The precision of the risk prediction was similar with both methods. Conclusions Delta-NT can be extrapolated for use in risk calculation between two populations with different distributions and medians of NT values. The precision of the risk estimate obtained is similar to that derived using MoMs. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.

Aim The aim of the present study is to determine whether the use of population parameters derived from meta-analysis produces better test characteristics in the first-trimester combined screening than those obtained from large single studies, when screening for Down syndrome (DS) in singleton pregnancies. Methods Retrospective analysis was done on a database of 4248 singleton pregnancies, including 13 cases of DS, for which the values of three markers used in the combined first-trimester test were available. The risk of DS was calculated for each mother from the different population parameters derived by meta-analysis or from two large single studies: the Fetal Medicine Foundation study (FMF) and the Serum, Urine and Ultrasound Screening Study (SURUSS). Results When the detection rate was fixed at about 85%, the false-positive rate was significantly higher (Chi-square = 53.49, p < 0.0001) when the parameters obtained by the meta-analysis (6.25%) were compared with the two single studies (FMF, 4.15% and SURUSS, 3.75%). Conclusions This study highlights the importance of selecting appropriate population parameters when insufficient DS cases are available in the study population. When screening for DS in singleton pregnancies during the first trimester, the use of population parameters derived from single large studies produced better test characteristics. Copyright © 2006 John Wiley & Sons, Ltd.

Objective To evaluate the utility of determining the presence/absence of nasal bone in a low-risk fetal population. Methods Prospective study of the presence/absence of nasal bone among 1800 consecutive unselected fetuses, with complete follow-up of results. Results An adequate sonographic evaluation of nasal bone was obtained in 1682 (93.44%) of the fetuses. Nasal bone was considered absent in 19 (1.06%) of 1790 fetuses with a normal karyotype and in 2 (28.57%) of the seven recorded cases of Down syndrome (DS). The overall first-trimester sensitivity for DS to the absence of nasal bone was two of the six cases (33.3%) and the false-positive rate was 1.13%. The positive predictive value for DS of the absence of nasal bone was 2/21 (9.52%). Conclusions In a low-risk population, the evaluation of the presence/absence of nasal bone in DS screening during the first trimester has a low sensitivity. First-trimester assessment of the nasal bone in population screening may play a lesser role than in the re-evaluation of high-risk pregnancies. Copyright © 2006 John Wiley & Sons, Ltd.

The amygdalopiriform transition area (APir) is often considered part of the lateral entorhinal cortex (Entl). However, in contrast to Entl, APir densely innervates the central extended amygdala (EAc) and does not project to the dentate gyrus. In order to gain a more comprehensive understanding of these territories, the afferent connections of APir were examined in the rat with retrograde (cholera toxin B subunit or FluoroGold) and anterograde tracers (Phaseolus vulgaris leucoagglutinin) and compared to those of the neighboring Entl. The results suggest that APir and Entl are interconnected and receive topographically organized hippocampal projections. Both are targeted by the olfactory bulb, the piriform, posterior agranular insular and perirhinal cortices, the ventral tegmental area, dorsal raphe nucleus, and locus coeruleus. Most importantly, the data reveal that APir and Entl also have specific inputs and should be viewed as separate anatomical entities. The APir receives robust projections from structures affiliated with the EAc, including the anterior basomedial and posterior basolateral amygdaloid nuclei, the gustatory thalamic region, parasubthalamic nucleus, and parabrachial area. The Entl is a major recipient for amygdaloid projections from the medial part of the lateral nucleus and the caudomedial part of the basolateral nucleus. Moreover, the medial septum, subicular complex, nucleus reuniens, supramammillary region, and nucleus incertus, which are associated with the hippocampal system, preferentially innervate the Entl. These data underscore that APir processes olfactory and gustatory information and is tightly linked to EAc operations, suggesting that it may play a role in reward mechanisms, particularly in hedonic aspects of feeding.

The efferent connections of the nucleus of the lateral olfactory tract (LOT) were examined in the rat with the Phaseolus vulgaris leucoagglutinin (PHA-L) technique. Our observations reveal that layers II and III of LOT have largely segregated outputs. Layer II projects chiefly ipsilaterally to the olfactory bulb and anterior olfactory nucleus, bilaterally to the anterior piriform cortex, dwarf cell cap regions of the olfactory tubercle and lateral shell of the accumbens, and contralaterally to the lateral part of the interstitial nucleus of the posterior limb of the anterior commissure. Layer III sends strong bilateral projections to the rostral basolateral amygdaloid complex, which are topographically organized, and provides bilateral inputs to the core of the accumbens, caudate-putamen, and agranular insular cortex (dorsal and posterior divisions). Layer II projects also to itself and to layers I and II of the contralateral LOT, whereas layer III projects to itself, to ipsilateral layer II, and to contralateral layer III of LOT. In double retrograde labeling experiments using Fluorogold and cholera toxin subunit b tracers, LOT neurons from layers II and III were found to provide collateral projections to homonymous structures on both sides of the brain. Unlike other parts of the olfactory amygdala, LOT neither projects directly to the extended amygdala nor to the hypothalamus. Thus, LOT seemingly influences nonpheromonal olfactory-guided behaviors, especially feeding, by acting on the olfactory bulb and on ventral striatal and basolateral amygdaloid districts that are tightly linked to lateral prefrontal cortical operations.

Experimental studies were conducted by injecting or feeding white spot syndrome virus (WSSV) derived from infected shrimp, Penaeus monodon (Fabricius), collected from the south-east coast of India, to five species of shrimp, two species of freshwater prawns, four species of crabs and three species of lobsters. All species examined were susceptible to the virus. Experimental infections in the shrimp had the same clinical symptoms and histopathological characteristics as in naturally infected P. monodon. A cumulative mortality of 100% was observed within 5–7 days in shrimp injected with WSSV and 7–9 days in shrimp fed with infected tissue. Two species of mud crab, Scylla sp., survived the infection for 30 days without any clinical symptoms. All three species of lobsters, Panulirus sp., and the freshwater prawn, Macrobrachium rosenbergii (De Man), survived the infection for 70 days without clinical symptoms. However, bioassay and histology using healthy P. monodon revealed that crabs, prawns and lobsters may act as asymptomatic carriers/reservoir hosts of WSSV. This is the first report to suggest the carrier/reservoir capacity of these hosts through histological and bioassay evidences. Ultrastructural details of the virus in experimentally infected shrimp, P. vannamei, (Boone), were also studied.

A multiplex PCR/DNA probe assay was used to monitor Babesia bovis, B. bigemina and Anaplasma marginale infection in cattle introduced to a Boophilus microplus-infested area in Veracruz, Mexico. Eight intact, 18-month-old, cross-bred beef cattle (four naive, Group A; four Babesia species--premunized, Group B) were immediately exposed to ticks after arrival and were clinically monitored from day 6 to day 98 post-exposure (PE) to ticks. Blood sample analysis for DNA detection by the MPCR/DNA probe assay showed that Group A animals were infected with B. bovis from day 11 up to day 22 PE, requiring treatment on days 17-20. Group B animals were detected positive to B. bovis on days 17-20, did not require treatment and remained persistently infected from days 70 to 84 PE. Treatment of Group A animals delayed the infection with B. bigemina. These animals became positive to the parasite on days 63-77 PE. In contrast, Group B animals (untreated) showed B. bigemina infection on days 21-26 and 63-84 PE. One animal was positive for A. marginale infection on days 63-66 PE, the rest of the animals became so on days 80-98 PE. All infected animals required treatment with oxytetracycline. Monitoring the triple hemoparasite infection with the MPCR/DNA probe assay provided important epidemiological information. Thus, precautionary measures can be established when cattle are moved to a babesiosis/anaplasmosis risk area.

The influence of 5 host plants, castor bean, alfalfa, mulberry, cotton and potato, on the susceptibility of the cotton leaf worm, Spodoptera littoralis (Boisd.) to a nuclear polyhedrosis virus (NPV) was investigated. Median lethal doses (LD50's) of NPV were determined in third-instar larvae by a leaf-disk bioassay. Any statistically significant difference in the third-instar S. littoralis larvae susceptibility to the S. littoralis NPV was observed when fed on mulberry, cotton or potato. On the other hand the larvae were significantly less susceptible to the NPV when fed on castor bean than when fed on alfalfa, mulberry, cotton or potato and were also significantly less susceptible when fed on alfalfa than when fed on mulberry, cotton or potato. No differences were observed in the infection process due to the plant on which the NPV was presented. Zusammenfassung Zum Einflus der Nahrungspflanze auf die Empfindlichkeit der Larven von Spodoptera littoralis (Boisd.) (Lep., Noctuidae) gegenuber dem Spodoptera-littoralis-Nuclearpolyedrosevirus (NPV) (Baculoviridae, Baculovirus) Es wurde der Einflus von 5 Nahrungspflanzenarten: Castor-Bohne, Alfalfa, Maulbeere, Baumwolle und Kartoffel, auf die Empfindlichkeit der Baumwolleulen-Raupen, Spodoptera littoralis, gegenuber dem Sp.-littoralis-Nuclearpolyedrosevirus (NPV) untersucht. Die mittleren letalen Dosen (LD 50) des NPV wurden fur die Drittlarven mit Hilfe des Blattscheibentests bestimmt. Zwischen den Futterarten Maulbeere, Baumwolle und Kartoffel wurden keine signifikanten Unterschiede in der NPV-Empfindlichkeit der S. littoralis-Larven festgestellt. Dagegen waren die Larven signifikant weniger empfindlich bei Futterung mit Castor-Bohne gegenuber Alfalfa, Maulbeere, Baumwolle oder Kartoffel. Ebenfalls eine signifikant geringere Empfindlichkeit bestand bei Futterung mit Alfalfa gegenuber Maulbeere, Baumwolle und Kartoffel. Bezuglich des Infektionsprozesses konnte kein Einflus durch die NPV-kontaminierte Pflanzenart festgestellt werden.